CoKon 74

A MAGYAR MITTEILUNGEN TUDOMANYOS AKADEMIA DER CSILLAGVIZSGALO STERNWARTE INTEZETENEK DER UNGARISCHEN AKADEMIE KOZLEMENYEI DER WISSENSCHAFTEN BUDAPEST - SZABADSAGHEGY Nr. 74. HAMID A. MAHDY and B. SZEIDL PERIOD CHANGES OF DWARF CEPHEIDS, I CY AQUARII, EH LIBRAE, DY PEGASI BUDAPEST, 1980

PERIOD CHANGES OF DWARF CEPHEIDS, I CY AQUARII, EH LIBRAE AND DY PEGASI ABSTRACT The period changes of the dwarf cepheids CY Aqr, EH Lib and DY Peg are discussed and O-C diagrams of these stars are constructed. EH Librae has a highly stable, constant period. The period of CY Aquarii changed suddenly in 1952 (Delta P = -1.81 x 10^-7 day = 0.016 sec). Before the abrupt change its period showed small fluctuations, such fluctuations have also been shown since that time. The period of DY Pegasi has become shorter during the past 45 years. At present no distinction can be made between the continuous change (at the rate Beta = -7.6 x 10^-13 days*cycle^-1 = -0.03 sec*century^-1 ) or the abrupt change of period (Delta P = -6.5 x 10^-8 day) in 1961. INTRODUCTION Interest has been shown in the period changes of pulsating variable stars. A dwarf cepheid lends itself well to investigations of this kind because of the large number of cycles passing in a relatively short time, say in 10 or 20 years. The bright (m<12 mag.) northern dwarf cepheids have been on the observing programme of our observatory for several years and very many photographic and photoelectric observations of these stars have been collected during the past almost fifty years. We feel that the time is now ripe for publishing our results and we plan to publish our observations and studies in a series of papers on the following stars: GP And, CY Aqr, RV Ari, YZ Boo, AD CMi, XX Cyg, DY Her, EH Lib, SZ Lyn, V567 Oph, DY Peg and AE UMa. In the present paper the results on CY Aqr, EH Lib and DY Peg are given. A description of the equipment used both for our photographic and our photoelectric observations can be found in several publications of the Konkoly observatory (see e.g. Olah and Szeidl, 1978). The observations published here represent the work of observers at the Konkoly Observatory. The photographic plates were obtained by I. Csada (2 plates, 45 exp.), L. Detre (3 plates, 73 exp.), D. Elter (4 plates, 126 exp.), I. Guman (4 plates, 65 exp.) and J. Sinka (1 plate, 23 exp.). The table below summarizes the photoelectric observations of our observers. Table 1 Number of observations Observer CY Aqr EH Lib DY Peg Total L. Detre - - 43 43 K. Gefferth - - 6 6 K. Olah - 48 - 48 L. Patkos 112 - - 112 L. Szabados - 81 34 115 B. Szeidl 50 193 472 715 J. Tatai - - 60 60 All the available observations on each star are discussed separately and we construct the O-C diagrams as a means of studying the period changes. CY AQUARII The star BD +0 4900 was discovered to be variable by Hoffmeister (1934) on Berlin-Babelsberg patrol plates. The star first received the preliminary designation 391.1934 Aqr, shortly after it was given its final name CY Aqr. Jensch's (1934a) early observation revealed a short period for this star - about 88 minutes. Hoffmeister confirmed this period. Later, Jensch (1934b) made a thorough visual investigation of this star. He also observed it photographically on old Babelsberg plates and was able to trace back its behaviour to 1928 to obtain the elements: Max.hel. = J.D. 2427658.4103 + 0.0610388d*E Because of its very short period CY Aqr has attracted considerable attention in the past almost fifty years. It has always been a favourite object of visual observations. About 500 visual maxima have been published due to the work of Ashbrook (1949, 1954), Barroso (1969), Braune et al. (1972, 1977, 1979), Busch (1973, 1975, 1977, 1978), Fedorov (1950), Figer (1978), Gossner and Ashbrook (1946), Graff (1936), Jensch (1934a, b, 1935, 1937), Kanishcheva et al. (1966), Kuhn (1951), Lange (1959), Lange and Nekrasova (1943), Lause (1934), Mandell et al. (1960), Martynov (1938), Miczaika (1938, 1946), Parenago (1935), Pohl and Kizilirmak (1964), Rabkin (1935), Romanov (1965), Selivanov (1934,1936), Smak (1959), Socher (1955), Soloviev and Shakovskoj (1958), Steinman (1958), Tsesevich (1948) and Wenzel (1950, 1952). The star's short period, however, renders it a difficult object to study with high precision by visual methods. A more rigorous study made it evident that the visual maxima are unusable for the investigation of minute period changes. In view of this, we simply ignored the visual observations and confined ourselves to photographic and photoelectric observations. From its discovery, the star was fairly regularly observed photographically until the early 50's and subsequently photoelectrically. As early as in 1934 and 1935, Balazs and Detre (1935), Dawson (1934), Gaposchkin (1935), Kulikovsky (1937), Schneller (1936) and Wachmann (1935) made extensive photographic observations. They used fairly short exposure times in order not to distort the light curve. It is interesting to note that Balazs and Detre found no significant variations either in phase or height of maximum light whereas Wachmann found some deviations of the individual light curves from the mean one. Gaposchkin (1935) and Muller (1935) made an attempt to determine the colour variation of CY Aqr. Muller's exposure times were fairly long (6-14 minutes) compared with the star's period therefore not too much significance should be ascribed to his observations. Wesselink (1941) started a thorough photographic investigation of this star at Leiden observatory a month after the announcement of its discovery. His last exposure was made in the autumn of 1940 so that his homogeneous material consisted of 604 exposures covering over 36000 periods. Because the exposure times were sufficiently short (1 3/4 - 2 minutes), the light curves were accurate enough to determine the correct value of the period: P = 0.0610384798 day +-.0000000061 The light curves appeared to be quite regular. For his period discussion Wesselink used a special point on the ascending branch of the light curves and did not give the epochs of maximum light. Using his mean light curve we were able to derive 18 times of maximum light from his rich observational material. During the war less attention was paid to this star. The only publication was that of Gossner and Ashbrook (1946) who published three photographic maximum times for the year 1944. Lohmann and Miczaika (1947), investigated the star's colour and light variation using their photographic and photovisual exposures made on two consecutive nights in 1946. The photovisual exposures were too long so they were not utilized to determine times of maximum light. Alania (1954, 1956) also made photographic observations and published two epochs of light maximum but because of their very low accuracy they have been omitted from our discussion of period changes. Both the photographic and the visual observations led to hopes of interesting results in the early 50's. Combining his observations with those of other astronomers Ashbrook (1954) stated that a phase jump of 0.0028 day had occurred about 1944-45. Sauer (1953) fancied waves on the visual light curve. Since 1950 a great number of photoelectric observations has been collected and we now know the photometric behaviour of the star fairly well. The light curve is smooth and is characteristic of the group to which the star belongs. Detre was the first to observe CY Aqr photoelectrically. On four nights in 1950 and 1954 he made some two hundred observations without filters and obtained seven times of maximum light. As these observations were available, we thought it reasonable to publish here the epochs of the maxima mentioned (see Table 3). Smith (1955) made a thorough investigation of the intrinsic variables with periods of less than 0.2 day and proposed the name "dwarf cepheids" for this group of stars. Among these objects he observed CY Aqr as well. Unfortunately, his observations are unavailable to the present authors. The first photoelectric observations to be published were those of Detre and Chang (1960). Their nearly two hundred photoelectric measurements were made at the Purple Mountain Observatory, China, without filters on four nights in 1959. The variation in height and phase of the maxima was less than 0.06 mag. and 0.001 day, respectively, which showed a good repetitive nature of the light variation. Detre and Chang published only two epochs of maximum light but their observations allowed the determination of three further epochs. They also noticed that the O-C diagram could no longer be approximated by a linear formula and they derived an ephemeris with a quadratic term: Max.hel. = J.D. 2427658.4079 + 0.061038576d*E - 7.42dx10^-13*E^2. Hardie and Tolbert (1961) secured over sixteen hundred UBV observations on thirteen nights in 1959 and 1960. They found the light curves to be somewhat variable in shape and amplitude (about 0.1 mag.) at different cycles. A discussion of all the data available to them suggested that the period was gradually decreasing and a second-degree solution seems to have appeared to them as being satisfactory: Max.hel. = J.D. 2431291.6657 + 0.061038475d*E - 6.0dx10^-13*E^2. These same authors published only four epochs of maxima (Hardie and Tolbert, 1961). Their observations did, however, make it possible to determine the times of 22 individual maxima. In the same year Geyer (1961) also published his study on short-periodic, pulsating variables. In his paper he gave an epoch of maximum light of CY Aqr. Sanwal (1962) reported 39 times of maxima of this star observed at the Uttar Pradesh State observatory, India, on twenty-two nights during the years 1959 to 1961. He found that the period had decreased significantly since the early observations. In 1960 on one night 36 narrow band observations were secured by McNamara et al. (1961) for a study of the physical parameters of CY Aqr. One epoch of maximum was given by McNamara et al.; a further one could, however, be deduced from their observations. Oosterhoff published Ponsen's five colour observations obtained on one night in August, 1961 (Ponsen and Oosterhoff, 1966). These observations have allowed us to determine an epoch of maximum light. Fitch et al. (1966) Also observed this star in the UBV system on two nights in 1964 and gave two times of maximum. In September-October 1964 Karetnikov and Medvedev (1966) also observed this star and collected almost 600 observations in B and V on 11 nights. They determined 11 times of maxima and, combining these epochs with all the others available to them, they obtained the new elements with a quadratic term: Max.hel. = J.D. 2431291.6657 + 0.061038475d*E - 6.35dx10^-13*E^2. Judging by their measurements, CY Aqr does not have a significant light curve variation (it being less than 0.1 mag. in the height of maximum in both colours). Zissell (1968) obtained more than 2000 photoelectric observations in V during the autumns of 1965 and 1966. These observations covered twenty-four cycles and made possible an accurate study of the variations in the period of CY Aqr. In his study Zissell used the epochs of the magnitude on the rising branch at which the rising and descending branches were separated by 0.220 period. The corresponding epochs of that critical magnitude are given in his paper only. Since in our investigations we have always used the times of maximum light we had to determine these times from Zissell's material. In contrast with Detre and Chang's (1960), Hardie and Tolbert's (1961) and Karetnikov and Medvedev's (1966) results Zissell stated that the period was essentially constant, at least between 1953 and 1966: P = 0.0610383405 day +-.0000000022 and that an ephemeris with a quadratic term was inadequate as a means of accounting for all the observations, Zissell also found from his observations that the individual cycles were significantly different, especially at maximum. The variation in the height of maximum exceeded 0.1 mag. Nather and Warner (1972) made sequential three colour observations of CY Aqr on two nights in November 1970, with fairly high time resolution. They did not find the irregularities on the light curves reported by other observers. Since Nather and Warner's technique was superior to that of other observers, the reported irregularities can obviously be explained by the inferior technique. According to Nather and Warner the light curve of CY Aqr is smooth but small changes in the height of light maximum may occur. Their excellent observations also show that no dependence of time of maximum on colours could be obtained. Elst (1972) looked for overtones in the pulsation of CY Aqr. He analysed Zissell's (1968) and his own 255 UBV observations and found a beat period of P_b = 0.1222 day. He remarked, however, that the beat phenomenon of this star was very small and therefore his results could not be regarded as definitive. Fitch (1973) reanalysed the published photoelectric observations and found that CY Aqr had a beat period of probable length 0.17766 day. His result can be interpreted using the present theory of pulsation whereas Elst's result is not consistent with that. Percy (1975) rediscussed all the observations available to him. According to his investigation the period of CY Aqr remained constant from 1934 to 1951, changed abruptly in 1951, and since then it has remained constant again. He also analysed several well observed light curves of this star by the maximum entropy method of spectral analysis and found that the beat period of Elst (1972) was not real; it was, rather, an artifact of his harmonic analysis method. A fairly high speed photoelectric photometry was carried out by Geyer and Hoffmann (1974, 1975a) with a double-beam photometer in B and V for five consecutive cycles in October 1973. They published six times of maxima. It is worth mentioning that their observations did not confirm the beat period given by either Elst (1972) or Fitch (1973). They considered it likely that the beat phenomenon of this star was fictitious. Recently, Ficarrotta and Romoli (1979) performed photoelectric observations in B and V, and published 14 times of light maxima for the years 1974 and 1977. Since 1935 a great number of photographic and photoelectric observations have been collected at the Konkoly Observatory, Budapest, in order to study the stability of the period of CY Aqr. The 267 photographic observations obtained on ten nights between 1935 and 1952 are given in Table 9. In measuring the photographic plates we used the comparison stars of Balazs and Detre (1935). These observations allowed us to determine 12 epochs of photographic maxima. The photoelectric investigation of this star in two colours was commenced at Konkoly Observatory in 1972. In all, 162 observations have been collected and are given in Tables 10-11. As a comparison star we used BD +0 4903. Table 2 gives the comparison stars for CY Aqr used by different authors. Table 2 Comp. star V B-V U-B References BD +0 4902 9.72 +0.76 +0.38 Hardie and Tolbert (1961) BD +0 4903 10.19 +1.32 Geyer (1961) 10.08 +1.19 present paper BD +0 4906 9.69 +0.50 Karetnikov and Medvedev (1966) The differential magnitudes were corrected for transformation to the standard system and for differential extinction. In Figure 1 all our photoelectric B and V observations are plotted against phase.

Figure 1: B and V light curves of CY Aqr In Table 3 we have gathered all the photographic and photoelectric maxima available to us; as we mentioned earlier, we disregarded the visual maxima. The O-C diagram (Figure 2) was completed by using the ephemeris: Max.hel. = J.D. 2434308.4310 + 0.061038395d*E.

Figure 2: O-C diagram of CY Aqr Table 3 Photographic and photoelectric maxima of CY Aqr year Hel.Max.J.D. Remarks E O-C mean E mean O-C n 1930 2426159.485 pg Je^1 -133505 -0.0151 -133505 -0.0151 1 1932 27013.293 pg Je^1 -119517 -0.0121 -119517 -0.0121 1 1933 413.220 pg Je^1 -112965 -0.0087 -112965 -0.0087 1 1934 671.5317 pg BD -108733 -0.0115 -108294 -0.0112 19 .5922 pg BD -108732 -0.0120 684.4712 pg Wa -108521 -0.0121 685.3875 pg Wa -108506 -0.0114 688.3780 pg Wa -108457 -0.0118 .5010 pg BD -108455 -0.0109 690.3940 pg BD -108424 -0.0101 692.5287 pg Wa -108389 -0.0117 .652 pg Ga -108387 -0.0105 693.3829 pg We^2 -108375 -0.0120 .4462 pg BD -108374 -0.0098 694.3590 pg Wa -108359 -0.0126 695.4600 pg BD -108341 -0.0102 697.4721 pg We^2 -108308 -0.0124 710.5949 pg Da -108093 -0.0129 712.3069 pg BD -108065 -0.0099 717.4332 pg Wa -107981 -0.0109 744.2302 pg BD -107542 -0.0097 .2909 pg BD -107541 -0.0101 1935 28045.3924 pg Pp -102608 -0.0110 -102360 -0.0108 14 046.3071 pg Ku^2 -102593 -0.0118 .4901 pg Ku^2 -102590 -0.0120 047.2826 pg Ku^2 -102577 -0.0130 .3464 pg Ku^2 -102576 -0.0102 .4064 pg Ku^2 -102575 -0.0112 .4065 pg Mu -102575 -0.0111 .4668 pg Ku^2 -102574 -0.0119 048.3823 pg Ku^2 -102559 -0.0119 074.3254 pg Pp -102134 -0.0102 .3860 pg Pp -102133 -0.0106 090.3189 pg Sc^2 -101872 -0.0087 .3800 pg Sc^2 -101871 -0.0087 094.2860 pg Sc^2 -101807 -0.0091 1936 397.5233 pg Pp - 96839 -0.0106 - 96184 -0.0110 11 422.4259 pg We^2 - 96431 -0.0116 .4874 pg We^2 - 96430 -0.0112 .5490 pg We^2 - 96429 -0.0106 423.3418 pg We^2 - 96416 -0.0113 .4027 pg We^2 - 96415 -0.0114 .4650 pg We^2 - 96414 -0.0102 .5251 pg We^2 - 96413 -0.0111 451.4802 pg We^2 - 95955 -0.0116 501.2275 pg We^2 - 95140 -0.0106 .2878 pg We^2 - 95139 -0.0113 1937 782.5534 pg We^2 - 90531 -0.0107 - 90531 -0.0107 1 1938 29195.3568 pg We^2 - 83768 -0.0099 - 83719 -0.0101 2 201.3382 pg We^2 - 83670 -0.0103 1939 568.3020 pg We^2 - 77658 -0.0093 - 77486 -0.0095 2 589.2989 pg We^2 - 77314 -0.0096 1940 2429880.4529 pg We^2 - 72544 -0.0088 - 72144 -0.0090 2 929.2833 pg We^2 - 71744 -0.0091 1944 31268.8978 pg GA - 49797 -0.0042 - 49486 -0.0043 3 296.9139 pg GA - 49338 -0.0048 297.8304 pg GA - 49323 -0.0038 1946 32091.3914 pg LM^2 - 36322 -0.0030 - 36310 -0.0029 4 .4532 pg LM^2 - 36321 -0.0023 092.3680 pg LM^2 - 36306 -0.0030 093.4056 pg Pp - 36289 -0.0031 1947 440.4700 pg Pp - 30603 -0.0030 - 30603 -0.0030 1 1950 33560.4638 pe De - 12254 -0.0027 - 12219 -0.0016 4 563.2728 pe De - 12208 -0.0015 .3350 pe De - 12207 -0.0003 .3947 pe De - 12206 -0.0017 1951 860.5310 pg Pp - 7338 -0.0003 - 7281 -0.0004 4 861.5070 pg Pp - 7322 -0.0009 .5679 pg Pp - 7321 -0.0010 (867.452 pg Al - 7224 -0.0376) 872.5565 pg Pp - 7141 +0.0007 1952 34253.5575 pg Pp - 899 0.0000 - 762 +0.0005 2 270.3440 pg Pp - 624 +0.0010 308.4310 pe Sm^3 0 0.0000 0 0.0000 1 1954 35032.4075 pe De + 11861 +0.0001 + 12071 -0.0003 4 036.3750 pe De + 11926 +0.0001 .4353 pe De + 11927 -0.0006 075.6218 pe HT^4 + 12569 -0.0008 1955 (337.422 pg Al + 16858 +0.0057) 1956 689.9121 pe HT^4 + 22633 -0.0009 + 22633 -0.0009 1 1958 36487.1936 pe Sa + 35695 -0.0029 + 36292 -0.0033 18 490.1231 pe Sa + 35743 -0.0033 .1837 pe Sa + 35744 -0.0037 .3068 pe Sa + 35746 -0.0027 491.2216 pe Sa + 35761 -0.0034 .2831 pe Sa + 35762 -0.0030 492.1979 pe Sa + 35777 -0.0038 .2595 pe Sa + 35778 -0.0032 .3201 pe Sa + 35779 -0.0036 541.2740 pe Ge + 36581 -0.0025 546.0949 pe Sa + 36660 -0.0037 .1555 pe Sa + 36661 -0.0041 549.0860 pe Sa + 36709 -0.0034 .1472 pe Sa + 36710 -0.0033 568.0690 pe Sa + 37020 -0.0034 569.0457 pe Sa + 37036 -0.0033 .1069 pe Sa + 37037 -0.0031 570.0834 pe Sa + 37053 -0.0032 1959 735.8044 pe HT^2 + 39768 -0.0015 + 41546 -0.0023 26 .8654 pe HT^2 + 39769 -0.0015 749.7819 pe HT^2 + 39997 -0.0018 .8432 pe HT^2 + 39998 -0.0015 792.6920 pe HT^2 + 40700 -0.0017 .7528 pe HT^2 + 40701 -0.0019 .8750 pe HT^2 + 40703 -0.0018 803.8012 pe HT^2 + 40882 -0.0015 1959 2436803.8617 pe HT^2 + 40883 -0.0020 832.6114 pe HT^2 + 41354 -0.0014 .7330 pe HT^2 + 41356 -0.0019 835.6017 pe HT^2 + 41403 -0.0020 .6624 pe HT^2 + 41404 -0.0023 842.6818 pe HT^2 + 41519 -0.0023 .7430 pe HT^2 + 41520 -0.0022 845.7345 pe HT^2 + 41569 -0.0015 871.1246 pe Sa + 41985 -0.0034 902.0108 pe DC^2 + 42491 -0.0026 .0716 pe DC^2 + 42492 -0.0029 903.0490 pe DC + 42508 -0.0021 906.0397 pe DC + 42557 -0.0023 928.0728 pe Sa + 42918 -0.0040 .1343 pe Sa + 42919 -0.0036 .9895 pe DC^2 + 42933 -0.0029 929.0511 pe Sa + 42934 -0.0024 .1105 pe Sa + 42935 -0.0040 1960 37195.7276 pe HT^2 + 47303 -0.0026 + 47759 -0.0032 21 .7894 pe HT^2 + 47304 -0.0018 196.6437 pe HT^2 + 47318 -0.0021 .7054 pe HT^2 + 47319 -0.0014 .7658 pe HT^2 + 47320 -0.0021 198.2906 pe Sa + 47345 -0.0032 202.1968 pe Sa + 47409 -0.0035 204.1506 pe Sa + 47441 -0.0029 222.1557 pe Sa + 47736 -0.0041 .2165 pe Sa + 47737 -0.0044 224.2303 pe Sa + 47770 -0.0048 225.6365 pe HT^2 + 47793 -0.0025 .6978 pe HT^2 + 47794 -0.0023 226.1231 pe Sa + 47801 -0.0042 233.6340 pe Mc + 47924 -0.0010 .6940 pe Mc^2 + 47925 -0.0021 250.1112 pe Sa + 48194 -0.0042 253.1013 pe Sa + 48243 -0.0050 255.1161 pe Sa + 48276 -0.0045 257.1307 pe Sa + 48309 -0.0041 279.1041 pe Sa + 48669 -0.0045 1961 524.5425 pe PO^2 + 52690 -0.0015 + 53450 -0.0038 6 578.1311 pe Sa + 53568 -0.0046 .1930 pe Sa + 53569 -0.0038 .2539 pe Sa + 53570 -0.0039 583.1360 pe Sa + 53650 -0.0049 .1980 pe Sa + 53651 -0.0039 1964 38643.4958 pe KM + 71022 -0.0041 + 71292 -0.0033 13 644.4117 pe KM + 71037 -0.0038 645.3895 pe KM + 71053 -0.0026 .4508 pe KM + 71054 -0.0023 652.4082 pe KM + 71168 -0.0033 .4693 pe KM + 71169 -0.0032 653.4454 pe KM + 71185 -0.0037 654.4835 pe KM + 71202 -0.0033 675.2981 pe KM + 71543 -0.0028 1964 2438675.3592 pe KM + 71544 -0.0027 676.3344 pe KM + 71560 -0.0041 680.730 pe Fi + 71632 -0.0033 .791 pe Fi + 71633 -0.0033 1965 39089.5647 pe Zi^2 + 78330 -0.0038 + 78330 -0.0038 1 1966 350.6861 pe Zi^5 + 82608 -0.0046 + 83001 -0.0040 22 .7490 pe Zi^5 + 82609 -0.0028 .8087 pe Zi^5 + 82610 -0.0041 .8692 pe Zi^5 + 82611 -0.0046 351.7253 pe Zi^5 + 82625 -0.0031 .8460 pe Zi^5 + 82627 -0.0045 355.6920 pe Zi^5 + 82690 -0.0039 .7546 pe Zi^5 + 82691 -0.0023 .8145 pe Zi^5 + 82692 -0.0035 .8763 pe Zi^5 + 82693 -0.0027 356.7300 pe Zi^5 + 82707 -0.0035 .7908 pe Zi^5 + 82708 -0.0038 .8527 pe Zi^5 + 82709 -0.0029 401.5920 pe Zi^5 + 83442 -0.0048 .6527 pe Zi^5 + 83443 -0.0051 .7139 pe Zi^5 + 83444 -0.0049 405.6204 pe Zi^5 + 83508 -0.0049 .6822 pe Zi^5 + 83509 -0.0041 .7428 pe Zi^5 + 83510 -0.0046 406.5980 pe Zi^5 + 83524 -0.0039 .6578 pe Zi^5 + 83525 -0.0051 .7196 pe Zi^5 + 83526 -0.0044 1970 40779.7783 pe El^2 +106021 -0.0044 +106768 -0.0052 5 1973 .8390 pe El^2 +106022 -0.0047 .9005 pe El^2 +106023 -0.0043 892.6364 pe NW +107870 -0.0063 894.6507 pe NW +107903 -0.0062 1972 41623.2647 pe Pp +119840 -0.0076 +119840 -0.0076 1 958.3639 pe GH +125330 -0.0091 +125344 -0.0089 6 959.2799 pe GH +125345 -0.0087 .3405 pe GH +125346 -0.0092 .4018 pe GH +125347 -0.0089 .4634 pe GH +125348 -0.0083 .5234 pe GH +125349 -0.0094 1974 42302.5015 pe FR +130968 -0.0060 +130987 -0.0074 7 .5607 pe FR +130969 -0.0079 303.4778 pe FR +130984 -0.0063 .5371 pe FR +130985 -0.0081 304.3927 pe FR +130999 -0.0070 .4533 pe FR +131000 -0.0074 .5126 pe FR +131001 -0.0092 1977 43401.3706 pe FR +148971 -0.0111 +148981 -0.0105 7 .4327 pe FR +148972 -0.0101 .4937 pe FR +148973 -0.0101 402.3478 pe FR +148987 -0.0106 .4086 pe FR +148988 -0.0108 .4699 pe FR +148989 -0.0105 .5311 pe FR +148990 -0.0104 1979 44158.3069 pe Pp +161372 -0.0120 +161372 -0.0120 1 Remarks to Table 3: Je = Jensch (1934b), BD = Balazs and Detre (1935), Wa = Wachmann (1935), Ga = Gaposchkin (1935), We = Wesselink (1941), Da = Dawson (1934), Ku = Kulikovsky (1937), Mu = Muller (1935), Sc = Schneller (1936), GA = Gossner and Ashbrook (1946), LM = Lohmann and Miczaika (1947), De = Detre (unpubl.), Al = Alania (1954, 1956), Sm = Smith (1955), HT = Hardie and Tolbert (1961), Sa = Sanwal (1962), Ge = Geyer (1961), DC = Detre and Chang (1960), Mc = McNamara et al. (1961), PO = Ponsen and Oosterhoff (1966), KM = Karetnikov and Medvedev (1966), Fi = Fitch et al. (1966), Zi = Zissell (1968), El = Elst (1972), NW = Nather and Warner (1972), GH = Geyer and Hoffmann (1974), FR = Ficarrotta and Romoli (1979), Pp = present paper pg = photographic, pe = photoelectric, ^1 = normal maxima, ^2 = maximum time determined by us, ^3 = as quoted by Sanwal (1962), ^4 = observed by Fitch, ^5 = maximum time determined by Fitch (1973) We are convinced, from the O-C diagram, that the period change of CY Aqr cannot be described by a quadratic term. Our results are in agreement with Percy's (Percy, 1975): the period of CY Aqr remained more or less constant until 1952, at that time it changed abruptly and became shorter after which it again remained constant. Using the yearly means of the O-C values in Table 3 we formed yearly mean epochs of maximum light. These mean photographic and photoelectric maxima of CY Aqr are given in Table 4. The data of this table were used to carry out a least-squares solution for the period before 1952 (C_1) and after it (C_2). The resulting ephemerides are: C_1(Max.hel.) = J.D. 2434308.4314 + 0.061038509d*E C_2(Max.hel.) = J.D. 2434308.4314 + 0.061038328d*E Table 4 Mean photographic and photoelectric maxima of CY Aqr year Mean Hel. Max. W E O-C_1 O-C_2 1930 J.D.2426159.485 pg 0 -133505 -0.0003 -- 1932 27013.293 pg 0 -119517 +0.0011 -- 1933 27413.220 pg 0 -112965 +0.0038 -- 1934 27698.3279 pg 2 -108294 +0.0008 -- 1935 28060.5301 pg 2 -102360 +0.0005 -- 1936 28437.5030 pg 2 - 96184 -0.0005 -- 1937 28782.5534 pg 1 - 90531 -0.0007 -- 1938 29198.3475 pg 1 - 83719 -0.0010 -- 1939 29578.8004 pg 1 - 77486 -0.0011 -- 1940 29904.8680 pg 1 - 72144 -0.0012 -- 1944 31287.8807 pg 2 - 49486 +0.0010 -- 1946 32092.1240 pg 2 - 36310 +0.0009 -- 1947 32440.4700 pg 1 - 30603 +0.0001 -- 1950 33562.6013 pe 2 - 12219 -0.0006 -- 1951 33864.0101 pg 2 - 7281 +0.0001 -- 1952 34261.9202 pg 1 - 762 +0.0001 -- 1952 J.D.2434308.4310 pe 2 0 -0.0004 -0.0004 1954 35045.2252 pe 2 + 12071 -- +0.0001 1956 35689.9121 pe 1 + 22633 -- +0.0002 1958 36523.6331 pe 2 + 36292 -- -0.0013 1959 36844.3299 pe 2 + 41546 -- +0.0001 1960 37223.5605 pe 2 + 47759 -- -0.0004 1961 37570.9294 pe 2 + 53450 -- -0.0006 1964 38659.9770 pe 2 + 71292 -- +0.0011 1965 39089.5647 pe 1 + 78330 -- +0.0011 1966 39374.6748 pe 2 + 83001 -- +0.0011 1970 40825.3732 pe 2 +106768 -- +0.0016 1972 41623.2647 pe 1 +119840 -- +0.0001 1973 41959.2187 pe 2 +125344 -- -0.0009 1974 42303.6599 pe 2 +130987 -- +0.0010 1977 43401.9816 pe 2 +148981 -- -0.0009 1979 44158.3069 pe 1 +161372 -- -0.0016

Figure 3: O-C_1 diagram of CY Aqr

Figure 4: O-C_2 diagram of CY Aqr The corresponding O-C_1 and O-C_2 diagrams are plotted in Figures 3 and 4, respectively. Some fluctuations with an amplitude of 0.002 day ~= 3 minutes are clearly seen, but these do not appear to be periodic. Obviously the reality of these fluctuations can be questioned. They may be caused by systematic differences between the results of different authors. But the phase shift around E = -60000 was already noticed by Ashbrook (1954). His result also supports the idea that the period of CY Aqr before and after the large period jump (1.81 x 10^-7 day ~= 0.016sec) has not been strictly constant, it has always been subject to small random variations (in this context see Balazs-Detre and Detre, 1965). EH LIBRAE The star BD -0 2911 (8.9m) = EH Lib was found to be variable in light by A.N. Vyssotsky on an objective prism plate. He took note of the variation in density across the width of its spectrum. Code (1950) observed the star photoelectrically on three successive nights, June 4 through June 6, 1950. He determined the type of variability and gave a preliminary period of the star as 0.08842 day. In the following year Ashbrook (1952) made 83 photographic observations which yielded three heliocentric Julian dates of maximum light and which resulted in the accurate new elements: Max.hel. = J.D. 2433673.1688 + 0.08841381d*E Since Code's photoelectric and Ashbrook's photographic observations a great number of visual observations have been collected. Batyrev (1951, 1953a, 1957, 1964) observed the star visually between 1951 and 1963 and, utilizing his some 560 observations, he gave the time of 23 individual light maxima. He stated that light curve variation was present but he could not determine the secondary period. Tsesevich (1956) also gave a visual normal maximum. The German amateurs (Pohl, 1954; Braune and Hubscher, 1967; Braune, Hubscher and Mundry, 1970, 1972, 1977, 1979; Braune and Mundry, 1973; Berthold, 1976) have been particularly busy in obtaining visual observations. Between 1951 and 1977 they determined 68 dates of visual maximum. Berdnikov (1972, 1975, 1977) also put EH Lib on his observing programme of dwarf cepheids. Between 1972 and 1975 he made nearly 700 visual estimations, determined more than 30 maxima, and gave four normal maxima; one for each year from 1972 to 1975. Mostly discussing the visual observations he suggested that the period of the star varied with a period of about 1800 days 20400 cycles and the form of the light curve changed. As we shall see later on these statements are completely erroneous. Because the observational errors of visual light estimation are always large and, in consequence, the errors in dates of visual light maxima are considerable, we have ignored all the observed visual maxima and have not listed them in Table 5. In a scrupulous period analysis they are of no value. Some photographic observations were also made on the star. Alania (1954), using only a few observations, gave a poorly determined time of photographic maximum. Although this is given in the table of maxima (Table 5), it has been disregarded in constructing the O-C diagram of EH Lib (Figure 6). Burnicki and Krygier (1958) photographically investigated the colour variation of the variable during its light variation. From May 1954 to May 1956, 66 exposures were made: 41 in the pg and 25 in the pv spectral region. Even though Burnicki and Krygier gave no epochs of maximum light, we were able to determine one normal maximum from their accurate measurements. The last observers to report on photographic observations were Harding and Penston (1966). Curiously enough their photographic photometry definitely indicated a period of less than 2 hours in 1965, and over a period of a year they deduced a period of 0.082478 day. In view of this, it is rather surprising that the maximum time given by them fits very well in the O-C diagram (Figure 6) calculated using our elements. We are convinced that the period was around 2h07m18.9s in 1965. Harding and Penston's observations were somewhat poorer, but unfortunately they did not publish their measurements and it is thus hard to judge their mistake. Fitch (1957) observed EH Lib photoelectrically in three colours of the UBV system, his observations totalled 6.1 cycles on 4 nights in 1955 and 1956. In a result inconsistent with the poor visual observations, he found that the light curve of the variable is quite regular and the height of maximum varies by less than +-0.015 mag. From a very accurate analysis of his photoelectric light curves of high precision he found a mean difference maximum minus median = +0.0086 +0.0003 m.e. Using this value we converted his 8 epochs of median magnitude to the epochs of maximum light (6 in 1955 and 2 in 1956) and these dates are given in Table 5. He also noted that "maximum brightness in blue and yellow occurs at the same phase, within the limits of error of the observations". Fitch's comparison star was BD -0 2909 with its magnitude and colours as follows: V = 10.26, B-V = +0.44 and U-B = -0.03. Using the observations from 1950 to 1956 Fitch gave the highly accurate ephemeris: Max.hel. = J.D. 2433438.6078 + 0.08841325d*E +-.0003 +-.00000002 In 1960 and 1961 Sanwal and Pande (1961) carried out photoelectric observations in blue and yellow lights on ten nights covering 15 cycles. They also found the light curve of this variable star quite regular and did not detect any differences between times of maximum brightness in blue and yellow light. They listed 9 epochs of maximum light for the year 1960 and 5 epochs for 1961. Their least-squares solution yielded the following very good elements: Max.hel. = J.D. 2433438.6079 + 0.08841324d*E +-.0003 +-.00000001 In 1960 Oosterhoff and Walraven (1966) obtained more than 400 five-colour measurements of EH Librae, that unambiguously show the strictly repetitive nature of the light variation. They published three new epochs of light maximum. Because Oosterhoff and Walraven took into account the visual observations of low weight, as well, their elements: Max.hel. = J.D. 2433438.6090 + 0.088413216d*E are less accurate than the elements determined by Fitch and by Sanwal and Pande. Fitch et al. (1966) made 120 photoelectric observations in UBV on three nights in 1964, and gave two dates of maximum. Using Fitch's (1957) old mean light curves we redetermined the two dates from their new observations. We have already listed these new epochs in Table 5. Among other variable stars Epstein (1969) observed EH Lib in 1966 in the four-colour system of Stromgren and Perry. Unfortunately the 7 published observations in V light are not sufficient to determine an epoch of maximum light. Table 5 Photographic and photoelectric maxima of EH Lib year Hel.Max.J.D. Remarks E O-C mean E mean O-C n 1950 2433438.6076 pe Co 0 -0.0002 0 -0.0002 1 1951 711.7165 pg As + 3089 +0.0002 3308 -0.0002 3 737.709 pg As 3383 -0.0008 743.722 pg As 3451 +0.0001 1953 (34485.518 pg Al 11841 +0.0090) 11868 -0.0003 2 487.454 pg Pp 11863 -0.0001 488.426 pg Pp 11874 -0.0006 1955 35223.7596 pe Fi 20191 0.0000 20271 +0.0002 6 .8478 pe Fi 20192 -0.0002 .9372 pe Fi 20193 +0.0008 225.7932 pe Fi 20214 +0.0001 243.7414 pe Fi 20417 +0.0004 .8298 pe Fi 20418 +0.0004 1956 599.958 pg BK^1 24446 +0.0001 24446 +0.0001 1 622.6799 pe Fi 24703 -0.0002 24704 -0.0001 2 .7686 pe Fi 24704 0.0000 1960 36996.4443 pe SP 40241 -0.0008 41170 +0.0001 12 37054.2674 pe SP 40895 0.0000 .3552 pe SP 40896 -0.0006 075.2222 pe SP 41132 +0.0009 .3109 pe SP 41133 +0.0012 .3982 pe SP 41134 +0.0001 077.1670 pe SP 41154 +0.0006 082.2054 pe SP 41211 -0.0006 105.1927 pe SP 41471 -0.0007 114.301 pe OW 41574 +0.0010 116.245 pe OW 41596 -0.0001 .334 pe OW 41597 +0.0005 1961 403.3217 pe SP 44843 -0.0012 44891 -0.0004 5 .4115 pe SP 44844 +0.0002 408.3624 pe SP 44900 0.0000 410.3074 pe SP 44922 -0.0001 412.3402 pe SP 44945 -0.0008 1964 38441.0300 pe FE^1 56580 +0.0009 56727 +0.0004 2 467.0225 pe FE^1 56874 -0.0001 1965 822.710 pg HP 60897 +0.0009 60897 +0.0009 1 1969 40365.6104 pe TR 78348 +0.0018 78515 +0.0021 8 368.6169 pe TR 78382 +0.0023 .7054 pe TR 78383 +0.0024 387.5371 pe TR 78596 +0.0021 .6253 pe TR 78597 +0.0018 .7142 pe TR 78598 +0.0023 388.5100 pe TR 78607 +0.0024 .5978 pe TR 78608 +0.0018 1970 794.6775 pe BH^1,2 83201 -0.0005 83201 -0.0005 1 1972 41476.4327 pe Pp 90912 +0.0002 90912 +0.0002 1 1974 42159.5129 pe Pp 98638 -0.0004 98766 -0.0003 4 162.5181 pe KM -98672 -0.0012 178.7868 pe MF 98856 -0.0005 182.4133 pe KM 98897 +0.0010 1975 515.5531 pe BC 102665 -0.0003 102940 -0.0002 15 1975 2442515.6410 pe BC +102666 -0.0008 519.5314 pe BC 102710 -0.0006 .6201 pe BC 102711 -0.0003 521.5654 pe BC 102733 -0.0001 541.4588 pe KM 102958 +0.0003 544.3758 pe KM 102991 -0.0003 .4653 pe KM 102992 +0.0008 547.3819 pe BC 103025 -0.0003 548.4427 pe Pp 103037 -0.0004 549.4154 pe BC 103048 -0.0003 .5032 pe BC 103049 -0.0009 551.4492 pe BC 103071 0.0000 .5375 pe BC 103072 -0.0001 577.4437 pe KM 103365 +0.0010 1976 871.5051 pe Pp 106691 0.0000 106701 +0.0001 6 .5069 pe KM 106691 +0.0018 .5933 pe KM 106692 -0.0002 872.4773 pe KM 106702 -0.0004 .5658 pe KM 106703 -0.0003 874.5107 pe KM 106725 -0.0005 1977 43249.6478 pe GE 110968 -0.0008 111108 -0.0001 7 254.5996 pe GE 111024 -0.0001 255.5728 pe GE 111035 +0.0006 .6613 pe GE 111036 +0.0007 256.6329 pe GE 111047 -0.0003 274.5807 pe GE 111250 -0.0004 287.5778 pe GE 111397 0.0000 1979 957.5732 pe Pp 118975 -0.0002 118975 -0.0002 1 Remarks to Table 5: Co = Code (1951), As = Ashbrook (1952), Al = Alania (1954), Fi = Fitch (1957), BK = Burnicki and Krygier (1958), Sp = Sanwal and Pande (1961), OW = Oosterhoff and Walraven (1966), FE = Fitch et al. (1966), HP = Harding and Penston (1966), TR = Terzan and Rutily (1974), BH = Boardman and Heiser (1972), KM = Karetnikov and Medvedev (1977), MF = McNamara and Feltz (1976), BC = Broglia and Conconi (1977), GE = Garrido et al. (1979), Pp = present paper pg = photographic, pe = photoelectric, ^1 = maximum time determined by us, ^2 = normal maximum Terzan and Rutily (1974) obtained 453 photoelectric observations in the UBV system on four nights in 1969. As a comparison star they used HD 132092 = BD -0 2906 whose magnitude and colours are: V = 9.27, B-V = +0.32 and U-B = +0.13. They gave eight dates of maximum light. The O-C deviations of these epochs are surprisingly high, the cause of this is not clear and has no explanation; it is most likely that these epochs are due to systematic error. Because of this their period (0.088413276) is slightly longer than the correct one. In 1970 Boardman and Heiser (1972) carried out uvby photometry of this star. They obtained 144 differential photoelectric observations on four nights. These observations enabled us to determine an accurate normal maximum. In their paper McNamara and Feltz (1976) made a detailed study of the radial velocity variations of EH Librae. In order to be able to calculate the correct phase of the measured radial velocities, they secured a maximum light observation in 1974 which is well-represented by our elements. Karetnikov and Medvedev (1977) obtained over 500 photoelectric observations close to B and V on 13 nights in the years 1974-1976. They determined 22 epochs of light maximum, 11 maxima in each colour. Since the earlier observations also showed that: there was no systematic difference between the times of maximum in different colours, we formed mean values of the epochs determined from the blue and yellow observations. In this way 11 times of maximum are added to the list of epochs of EH Lib (Table 5) from Karetnikov and Medvedev's observations. Broglia and Conconi (1977) made more than 900 photoelectric B and V observations (443 in B and 462 in V). They detected small variations in the height of the maxima, but they did not find any variations in the minima. They failed, however, to see any evidence of periodic oscillation in the O-C residuals, in particular with a period near 1800 days (Berdnikov, 1975). Their measurements indicate some cycle-to-cycle variations, and if this phenomenon is periodic they propose a period of about 300 cycles (~=27 day). Taking into account the visual observations, too, but with low weight, they found the elements: Max.hel. = J.D. 2433438.6082 + 0.0884132445d*E +-.0002 +-.0000000020 On discussing the period changes they arrived at the conclusion that the period changed abruptly on two occasions. This conclusion is, however, based only on Terzan and Rutily's (1974) observations. Garrido et al. (1979) observed EH Lib in B and V on six nights. They collected 146 photoelectric observations and determined 7 times of maximum light. We rediscussed these observations and by fitting Fitch's (1957) mean B and V light curves to their observations we redetermined the maximum times. In Table 5 these newly determined maxima are given. Garrido et al. (1979) made an effort to find secondary periodicities of EH Lib. Their power spectrum, however, showed "no features which could be regarded as certainly significant". The reality of all periods other than the fundamental one is questioned. This variable star has long been on the programme at the Konkoly Observatory. It was observed photographically in 1953 and two times of light maximum could be determined for that year. Our 65 photographic observations made on three nights are given in Table 12. We observed the star photoelectrically on five nights in 1972, 1974, 1975, 1976 and 1979 and collected 322 observations in B and V. BD -0 2909 was used as a comparison star, its magnitude and colours were adopted from Fitch (1957) (Tables 13-14). These observations yielded five times of maximum light which are included in the table of epochs of maximum of EH Librae (Table 5). Our photoelectric observations also clearly show that EH Lib is a dwarf cepheid with a stable light curve of strictly repetitive character.

Figure 5: B and V light curves of EH Lib Since the visual observations are of such low weight relative to the photoelectric observations it did not seem worthwhile to include them in a new solution. Using only the photoelectric maxima we cannot detect any change in the period of EH Lib in the past almost 30 years (2433400-2444000). A least-squares solution yields the following elements: Max.hel. = J.D. 2433438.6078 + 0.088413243d*E.

Figure 6: O-C diagram of EH Lib Berdnikov (1977) believed that a periodic change with a cycle length of 1800 days in the period of EH Lib is present. Our O-C diagram does not show this phenomenon. Obviously the visual observations of poor quality led him to the erroneous interpretation. DY PEGASI The variability of DY Peg = BD +16 4877 (9.3m) = HD 218549 (F5) = 112.1934 = P 5726 was discovered by Morgenroth (1934) on the Babelsberg survey plates. First Soloviev (1938) made a series of visual observations of this star in August and September 1938 and he determined the type and period of the light variability. His 14 visual maxima enabled him to give: Max.hel. = J.D. 2429169.1664 + 0.0729256d*E. Of course, the very short period attracted the attention of many visual observers to this star. The accuracy of visual observations is usually far too low so we have simply listed the references to these observations without giving full particulars. Ahnert (1938, 1939) observed, the star back in October 1938 and confirmed Soloviev's elements. Bancilhon and Schmitt (1940), Batyrev (1953b, 1955, 1962), Kuhn (1951), Lange (1944, 1959), Mandell (1958a, b), Mandell and Grigorevsky (1959), Satanova and Grigorevsky (1957), Soloviev (1940a, b, 1952) and Steinman (1958) made roughly 5000 further visual estimates. In particular, the German amateurs (Braune and Hubscher, 1967; Braune, Hubscher and Mundry, 1970, 1972, 1977, 1979; Braune and Mundry, 1973; Busch, 1973, 1975, 1976, 1977, 1978; Domke and Pohl, 1952; Dueball and Lehmann, 1964; and Pohl, 1954) were busy in obtaining visual observations. The most thorough investigation of visual observations was that of Grigorevsky and Mandell (1960). They made use of their own 3061 visual observations, too. From more than 500 maxima (observed up to 1958) they deduced the following elements: Max.hel. = J.D.2436071.42469 + 0.0729263727d*E +-.00028 +-.0000000076 According to their visual observations the star shows fairly strong light curve variations, especially in heights of maximum (0.3 mag.). Soloviev (1938) was the first to refer to this effect, but Lange (1944) soon questioned it. Grigorevsky and Mandell suggested a period of 0.2554 day for this secondary variation. These results are, however, hardly acceptable. As we will see later on, modern photoelectric observations show only a fluctuation-of 0.04 mag. in the heights of the maxima. obviously the visual observations have errors in the order of 0.3 mag., and no finer results can be deduced from them. Grigorevsky and Mandell claimed that they had found a long term variation in the phase of the light maxima of DY Peg. They gave a period of 4529*P = 330.28 days and an amplitude of 10 minutes for this long-term variation. The first valuable photographic observations of this star were obtained by Schneller (1938) and he gave two epochs of light maximum. In his two papers Steinmetz (1946, 1948) published 1874 photographic and 419 photovisual exposures. The observations span an interval from 28 July 1943 to 12 September 1947. He determined a revised value of the period, equal to 0.072926355 day from the complete photographic material and found this period to be constant during the whole interval of more than 20000 periods covered by his observations. In his discussions Steinmetz used the point on the rising branch at brightness Delta m = -0.46 mag. and listed 46 epochs of that particular point. Unfortunately he did not give the epochs of observed maxima. We used the mean light curve of Steinmetz and have derived a phase difference of Delta Phi = Phi(max) - Phi(Delta m = -0.46) = 0.088p = 0.0064d between the time of maximum light and Steinmetz's favoured point. Adding this value Delta Phi to the epochs given by Steinmetz we were able to determine the times of his photographic maxima. We then formed means of these times for the years 1943 (n=6), 1944 (n=10), 1945 (n=3), 1946 (n=3) and 1947 (n=24), these are given in Table 7. We should like to mention here that Quigley and Africano (1979) followed another procedure. They determined the times of maxima observed by Steinmetz by fitting his original data to a parabola. Obviously in this way they obtained maxima which were systematically delayed. Alania (1954, 1956) also observed the star photographically and gave an epoch of maximum light. His observation can, however, be accepted only with reserve. The very first photoelectric observations were made by Hiltner (Iriarte, 1952). On two nights, 19 and 20 July 1948, Hiltner obtained 301 observations in one colour which enable us to determine three times of maximum light. The light curve did not seem to repeat in all details, especially near minimum light. Masani and Broglia (1954) obtained 573 photoelectric observations in blue and 523 in yellow light between 10 October and 14 November, 1953. Their light curve shows some non-repetitive character from cycle to cycle and the deviations are certainly larger than the observational errors. Masani and Broglia determined 28 epochs of maximum light based on their own observations but three were in fairly large error (they gave their epochs with an accuracy of 0.001 day only) and we have therefore omitted the three erroneous epochs from our table of maximum times (Table 7). Hardie and Geilker (1958) obtained the first complete light curves in the UBV system for DY Peg in 1956. They published 1633 photoelectric observations (500 in V, 614 in B and 519 in U). Having analysed the data they found the general character of the light curves to be repetitive, however, no two cycles were alike in detail. The irregularities did not appear to reveal any systematic trend during the time covered by their observations. It was found that there was a variation of 0.04 mag. at maximum in V. Hardie and Geilker did not give their observed times of maxima. Using their original published magnitude data we were able to determine 18 epochs of light maximum (6 in V, 7 in B and 5 in U). These times are given in Table 7. In 1957 and 1960 Broglia (1961) secured 170 yellow photoelectric observations and gave five further epochs of maximum light. From his observations he found the amplitude of DY Peg to be slightly variable (some hundredths in magnitude). The new elements derived by him are: Max.hel. = J.D. 2434696.39682 + 0.072926371d*E +-.00009 +-.000000002 From 23 July to 16 October 1963 Karetnikov and Medvedev (1964) observed the star photoelectrically at the Odessa Observatory with an 8-inch refractor. Oddly enough they found that the form of the light curve changed significantly and very rapidly. The variations in the amplitude of DY Peg exceeded Delta A~=0.4 mag. Unusual humps occurred on both the ascending and descending branches of its light curve. Karetnikov and Medvedev investigated the phase of these humps and thought to find a correlation with a secondary period. They proposed P_s=0.255413 day for its value. In that all other photoelectric observations before and after 1963 have not shown any evidence for the strong light curve variation we have to accept Karetnikov and Medvedev's results, but we do so with reserve. We tend to believe that these irregular variations are an artifact of their observing technique rather than intrinsic to DY Peg. Because of this we have given only the mean moment of their maxima in Table 7. A further 54 UBV observations were published by Fitch et al. (1966). They also gave an epoch of maximum light which was determined as the time of the brightest observed point in V light. Using our mean photoelectric light curves we redetermined the time of maximum light from Fitch et al.'s data. In order to demonstrate the usefulness of their technique of sequential photoelectric photometry Warner and Nather (1972) observed DY Peg on two nights in November 1970. They have not published the observations, but only the graphs of the two observed light curves. From their figures we could read off two epochs of light maximum. We must, however, admit that the captions of their figures are inconsistent with the time scales on the horisontal axis. This ambiguity should be kept in mind. The most important conclusion of Warner and Nather's observation is that the light variation with phase in each colour is smooth but small changes may occur from cycle to cycle. Geyer and Hoffmann (1974, 1975b) carried out photoelectric photometry of this star in B and V with a double-beam photometer. They observed six cycles on two nights and gave six epochs of maxima. One of them (J.D. 2441957.5998) is somewhat uncertain but it does not significantly affect the average O-C value of the six maxima. Geyer and Hoffmann concluded that a short period beat phenomenon was not present in this variable and the light curve was smooth without anomalies. While testing an amateur photoelectric photometer Heiser (1976) observed DY Peg on 22 November 1975. He gave two times of light maxima (Braune, Hubscher and Mundry, 1979), one of which could be determined more accurately using the graph in his paper (Heiser, 1976). Recently Quigley and Africano (1979) carried out a high-speed photometry of this variable at the McDonald Observatory in order to update the star's ephemeris. The times of 19 maxima were recorded between November 1976 and 1977. Combining these with more than one hundred selected times of maxima they arrived at a revised ephemeris: Max.hel. = J.D. 2432751.96195 + 0.072926332d*E Most of the selected times of maxima were calculated by Quigley and Africano using a least-squares fit of the light curve data near the maximum to a parabola. Since the maximum of short periodic variables is asymmetric this fit obviously results in an epoch which may give rise to a systematic delay of 0.001 day. Therefore, Pogson's or any other "classical" method certainly give a better estimation of epoch of maximum light. Comparing the times of maximum light determined by us with those calculated by Quigley and Africano we came to the conclusion that their epochs of maxima have a lag of +0.0005d. The corrected value of mean (O-C) is also given in Table 7 and in calculating the mean maximum of Quigley and Africano we have already taken this correction into consideration (Table 8). Using the 122 entries of their Table I and Table II they also estimated the rate (Beta) of change of the period assuming that the O-Cs had a quadratic dependence on cycle numbers. They obtained the value Beta=-6x10^-12 days*day^-1=-0.02 sec*century^-1 for the rate of change. The photoelectric observations of this star were commenced at the Konkoly Observatory in 1954. The 1954 observations were carried out without using any filter but the 1960 observations were already made in the BV system. Detre's observations of 1954 enabled us to determine one time of maximum light. Between August 1960 and August 1979 some 615 photoelectric BV observations were obtained. The 1974 observations were made with the 20 inch reflector of our Mountain Station; the others were carried out with the 24 inch telescope at Budapest. The two colour observations are given in Tables 15-16 and are plotted against phase in Figure 7. The comparison and check stars are given in Table 6. Their magnitudes and colours are adopted from Hardie and Geilker (1958). Table 6 star BD V B-V U-B comparison +16 4878 9.80 +0.59 +0.10 check +16 4876 10.94 +0.53 +0.06

Figure 7: B and V light curves of DY Peg We have not found any significant shift in time between the blue and yellow maxima. Some small changes of the light curve (e.g. in maximum about 0.05 mag.) have, however, been recorded. Whether these minute changes are periodic or not is open to further investigation. Our observations do not confirm the 0.255 day secondary period and definitely contradict the 330 day long-term variation stated by Grigorevsky and Mandell (1960). Obviously they simply underestimated the errors of visual recordings and identified the observational scatter with real changes. Table 7 Photographic and photoelectric maxima of DY Peg year Hel.Max.J.D. Remarks E O-C mean E mean O-C n 1938 2429193.4456 pg Sc - 48796 -0.0024 - 48789 -0.0012 2 194.4691 pg Sc - 48782 +0.0001 1943 31022.0744 pg St^1,2 - 23721 -0.0014 - 23721 -0.0014 1 1944 310.4978 pg St^1,2 - 19766 -0.0016 - 19766 -0.0016 1 1945 764.3924 pg St^1,2 - 13542 -0.0005 - 13542 -0.0005 1 1946 32092.4147 pg St^1,2 - 9044 -0.0009 - 9044 -0.0009 1 1947 408.0396 pg St^1,2 - 4716 -0.0011 - 4716 -0.0011 1 1948 751.8884 pe Ir^1 - 1 0.0000 + 4 0.0000 3 .9613 pe Ir^1 - 0 0.0000 752.9093 pe Ir^1 + 13 0.0000 1953 (34626.462 pg Al + 25704 +0.0023) + 26533 +0.0005 25 661.3915 pe MB + 26183 0.0000 .4644 pe MB + 26184 0.0000 662.3403 pe MB + 26196 +0.0008 .4857 pe MB + 26198 +0.0004 .5589 pe MB + 26199 +0.0006 689.3228 pe MB + 26566 +0.0006 690.3437 pe MB + 26580 +0.0005 .4165 pe MB + 26581 +0.0004 691.2919 pe MB + 26593 +0.0007 .3646 pe MB + 26594 +0.0004 .4376 pe MB + 26595 +0.0005 692.2401 pe MB + 26606 +0.0008 .3138 pe MB + 26607 +0.0016 .3858 pe MB + 26608 +0.0007 .4585 pe MB + 26609 +0.0004 693.2613 pe MB + 26620 +0.0010 .3338 pe MB + 26621 +0.0006 .4057 pe MB + 26622 -0.0004 .4789 pe MB + 26623 -0.0001 695.3021 pe MB + 26648 -0.0001 .3756 pe MB + 26649 +0.0005 .4487 pe MB + 26650 +0.0007 696.2515 pe MB + 26661 +0.0013 .3242 pe MB + 26662 +0.0010 .3966 pe MB + 26663 +0.0005 1954 35070.2901 pe De + 31790 +0.0007 + 31790 +0.0007 1 1956 745.5885 pe HG^1 + 41050 +0.0013 + 41292 +0.0015 18 .6611 pe HG^1 + 41051 +0.0009 .7343 pe HG^1 + 41052 +0.0012 .8069 pe HG^1 + 41053 +0.0009 760.6847 pe HG^1 + 41257 +0.0017 .7576 pe HG^1 + 41258 +0.0017 762.5808 pe HG^1 + 41283 +0.0017 .6536 pe HG^1 + 41284 +0.0016 .7266 pe HG^1 + 41285 +0.0017 .8003 pe HG^1 + 41286 +0.0025 770.6031 pe HG^1 + 41393 +0.0021 .6753 pe HG^1 + 41394 +0.0014 .7488 pe HG^1 + 41395 +0.0020 771.6229 pe HG^1 + 41407 +0.0010 1956 2435771.6958 pe HG^1 + 41408 +0.0009 773.6654 pe HG^1 + 41435 +0.0015 .7375 pe HG^1 + 41436 +0.0007 780.6664 pe HG^1 + 41531 +0.0016 1957 36155.3623 pe Br + 46669 +0.0020 + 46715 +0.0019 3 160.3214 pe Br + 46737 +0.0021 .3939 pe Br + 46738 +0.0017 1960 37164.5170 pe Pp + 60507 +0.0021 + 60596 +0.0016 7 165.5375 pe Pp + 60521 +0.0017 167.4320 pe Pp + 60547 +0.0001 168.5276 pe Br + 60562 +0.0018 174.4348 pe Br + 60643 +0.0019 178.3734 pe Pp + 60697 +0.0025 .4451 pe Pp + 60698 +0.0013 1963 38276.8624 pe KM^2 + 75760 +0.0022 + 75760 +0.0022 1 1964 655.8598 pe Fi^1 + 80957 +0.0014 + 80957 +0.0014 1 1970 40895.6447 pe WN^3 +111670 -0.0001 +111684 0.0000 2 897.6138 pe WN^3 +111697 0.0000 1972 41535.5012 pe Pp +120444 +0.0008 +120444 +0.0008 1 1973 937.4701 pe GH +125956 -0.0003 +126216 +0.0003 8 .5444 pe GH +125957 +0.0011 957.3785 pe GH +126229 -0.0008 .4535 pe GH +126230 +0.0013 .5243 pe GH +126231 -0.0008 .5998 pe GH +126232 +0.0018 963.4324 pe Pp +126312 +0.0003 984.3615 pe Pp +126599 -0.0005 1974 42279.4210 pe Pp +130645 -0.0009 +130645 -0.0009 1 1975 739.2955 pe He^4 +136951 +0.0001 +136951 +0.0001 1 1976 43085.6951 pe QA +141701 -0.0004 +141725 -0.0002* 6 .7684 pe QA +141702 0.0000 (-0.0007) .8403 pe QA +141703 -0.0010 088.6860 pe QA +141742 +0.0005 .7582 pe QA +141743 -0.0002 089.7064 pe QA +141756 0.0000 1977 305.9329 pe QA +144721 -0.0001 +145201 +0.0003* 13 307.8308 pe QA +144747 +0.0017 (-0.0002) .9023 pe QA +144748 +0.0003 348.8143 pe QA +145309 +0.0006 .8867 pe QA +145310 +0.0001 .9598 pe QA +145311 +0.0003 350.7833 pe QA +145336 +0.0006 .8554 pe QA +145337 -0.0002 .9288 pe QA +145338 +0.0003 351.8042 pe QA +145350 +0.0005 .8765 pe QA +145351 -0.0001 353.7728 pe QA +145377 +0.0001 .8459 pe QA +145378 +0.0003 1979 44113.5179 pe Pp +155795 -0.0013 +155795 -0.0013 1 Remarks to Table 7: Sc = Schneller (1938), St = Steinmetz (1946, 1948), Ir = Iriarte (1952), Al = Alania (1956), MB = Masani and Broglia (1954), De = Detre (unpubl.), HG = Hardie and Geilker (1958), Br = Broglia (1961), KM = Karetnikov and Medvedev (1964), Fi = Fitch et al. (1966), WN = Warner and Nather (1972), GH = Geyer and Hoffmann (1974), He = Heiser (1976), QA = Quigley and Africano (1979), Pp = present paper pg = photographic, pe = photoelectric, ^1 = determined by us, ^2 = mean epoch, ^3 = read from Warner and Nather's figures, ^4 = read from Heiser's figure, ^* = the mean value has been decreased by 0.0005 day (see text)

Figure 8: O-C diagram of DY Peg In order to analyse the period changes of this variable star we have collected all the available times of photographic and photoelectric maxima in Table 7. Again we left the visual observations out of consideration because they proved to be of no value. The O-C values have been computed with the linear formula: C(Max.hel.) = J.D. 2432751.9613 + 0.072926332d*E. For each year a mean O-C value mean(O-C) and a mean epoch number mean(E) were formed and then a yearly mean epoch of the observed light maxima was calculated. These epochs are given in Table 8. The data of this table were used to carry out least-squares solutions. First we tried to make an approximation with two straight lines and obtained the linear ephemerides: C_1(Max.hel.) = J.D. 2432751.9609 + 0.072926372d*E before J.D. 2437500; E<65000 and C_2(Max.hel.) = J.D. 2432751.9658 + 0.072926297d*E after J.D. 2437500; E>65000. Table 8 Mean photographic and photoelectric maxima of DY Peg year Mean Hel. Max. W E O-C_1 O-C_2 O-C_3 1938 J.D.2429193.9573 pg 0 - 48789 +0.0012 -- +0.0025 1943 31022.0744 pg 1 - 23721 0.0000 -- +0.0003 1944 31310.4978 pg 1 - 19766 -0.0004 -- -0.0002 1945 31764.3924 pg 1 - 13542 +0.0004 -- +0.0005 1946 32092.4147 pg 1 - 9044 -0.0001 -- -0.0002 1947 32408.0396 pg 1 - 4716 -0.0005 -- -0.0007 1948 32752.2530 pe 2 + 4 +0.0004 -- +0.0002 1953 34686.9162 pe 2 + 26533 -0.0001 -- -0.0004 1954 35070.2901 pe 1 + 31790 -0.0002 -- -0.0004 1956 35763.2369 pe 2 + 41292 +0.0002 -- +0.0002 1957 36158.7168 pe 2 + 46715 +0.0004 -- +0.0005 1960 37171.0069 pe 2 + 60596 -0.0004 -- 0.0000 1963 38276.8624 pe 1 + 75760 -- +0.0003 +0.0006 1964 38655.8598 pe 1 + 80957 -- -0.0002 -0.0001 1970 40896.6658 pe 1 +111684 -- -0.0006 -0.0008 1972 41535.5012 pe 1 +120444 -- +0.0005 +0.0002 1973 41956.5774 pe 2 +126218 -- +0.0002 0.0000 1974 42279.4210 pe 1 +130645 -- -0.0009 -0.0010 1975 42739.2955 pe 1 +136951 -- +0.0004 +0.0003 1976 43087.4450* pe 2 +141725 -- -0.0002 -0.0002 1977 43340.9374* pe 2 +145201 -- +0.0004 +0.0005 1979 44113.5179 pe 1 +155795 -- -0.0003 0.0000 *The mean epoch has been decreased by 0.0005 day (see text). The corresponding O-C values are given in Table 8 under the headings O-C_1 and O-C_2. If the period had really a sudden change around J.D. 2437500, and before and after it the period was constant, the value of the period change was Delta P = -6.5 x 10^-8 day. The second order fit yielded the following formula: C_3(Max.hel.)= J.D. 2432751.9611+0.072926384d*E-3.813x10^-13*E^2. (C_3 was calculated in such a way that all the mean epochs - except Schneller's - were given equal weight.) In this case beta = -7.6x10^-13 day*cycle^-1 = -10.4x10^-12 days*day^-1 = = -0.03 sec*century^-1 in rough agreement with the estimates of Quigley and Africano (1979). At present, no difference can be made between the two approximations because 1/n^2 Summa{(O-C_1)^2 + (O-C_2)^2} and 1/n^2 Summa(O-C_3)^2 are in the same order. Further observations can only settle which approximation is the correct one. GENERAL REMARKS The number of dwarf cepheids investigated here is insufficient for making any definite conclusion on the possible evolutionary changes of the periods. Nevertheless, some comments can be made. CY Aqr and DY Peg can definitely be identified with the low-metal Population II (Breger, 1980) and both variable stars show decreasing periods; in contrast, EH Lib exhibits a normal Population I nature and has a very stable, constant period. The periods of both CY Aqr and DY Peg show some small random fluctuations, too, which are reflected in their O-C diagrams. The light curve of EH Lib is also stable whereas the light curves of CY Aqr and DY Peg show small cycle-to-cycle changes the character of which are still obscure. Further high speed photoelectric observations are needed in order to disentangle this problem. Acknowledgements: We should like to express our thanks to all our colleagues who took part in the observations. We are also indebted to Miss Katalin Olah for measuring some of the photographic plates. It is a pleasure to acknowledge those concerned with the preparation of the manuscript. Budapest-Szabadsaghegy, 8 January, 1980 REFERENCES Ahnert, P., 1938, Beobachtungs-Zirkulare 20.49 1939, ibid. 21.8 Alania, I.F., 1954, Astr. Circ. 146.14 1956, ibid. 173.20 Ashbrook, J., 1949, Astron. J. 54.168 1952, ibid. 57.64 1954, ibid. 59.6 Balazs, J. and Detre, L., 1935, Astron. Nachr. 256.87 1965, Kl. Veroff. Remeis-Sternw. Bamberg IV. 40.184 Bancilhon, O. and Schmitt, M.A., 1940, Journal des Observateurs XXIII. No. 8-9.109 Barroso, J., 1969, Inf. Bull. Var. Stars No. 341 (IBVS N°.341) Batyrev, A.A., 1951, Per. Zvezdy 8.308 and Astr. Circ. 118.9 1953a, Per. Zvezdy 9.225 1953b, ibid. 9.300 1955, ibid. 10.292 1957, ibid. 12.139 Batyrev, A.A., 1962, Per. Zvezdy 14.230 1964, ibid. 15.280 Berdnikov, L.N., 1972, Per. Zvezdy Suppl. 1.387 1975, ibid. 2.199 1977, ibid. 3.335 Berthold, T., 1976, Mitt. Verand. 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Nachr. 282.235 Pohl, E. and Kizilirmak, A., 1964, Astron. Nachr. 288.69 Ponsen, J. and Oosterhoff, P.Th., 1966, B.A.N. Suppl. 1.3 Quigley, R. and Africano, J., 1979, P.A.S.P. 91.230 Rabkin, S., 1935, Per. Zvezdy 5.27 Romanov, Ju.S., 1965, Per. Zvezdy 15.523 Sanwal, N.B., 1962, The Observatory 82.24 Sanwal, N.B. and Pande, M.C., 1961, The Observatory 81.199 Satanova, E.A. and Grigorevsky, V.M., 1957, Astr. Circ. 187.17 Sauer, M., 1953, Astron. Nachr. 282.178 Schneller, H., 1936, Astron. Nachr. 259.11 1938, Die Sterne 18.277 (Not available to the present authors) Selivanov, S.M., 1934, Tadjik Obs. Circ. No.2 1936, Per. Zvezdy 5.89 Smak, J., 1959, Acta Astr. 9.161 Smith, H.J., 1955, Astron. J. 60.179 and Thesis, Harvard Univ. (Not available to the present authors) Socher, H., 1955, Mitt. Sternw. Wien 7.118 Soloviev, A.V., 1938, Tadjik Obs. Circ. No.37 1940a, ibid. No.44 Soloviev, A.V., 1940b, Per. Zvezdy 5.340 1952, ibid. 9.94 Soloviev, A.V. and Shakovskoj, N.M., 1958, Tadjik Ann. 7.45 Steinman, G.S., 1958, Astr. Circ. 190.23 Steinmetz, C.H.D., 1946, B.A.N. 10.178 1948, B.A.N. 10.391 Terzan, A. and Rutily, B., 1974, Astron. Astrophys. Suppl. 16.155 Tsesevich, V.P., 1948, Odessa Izv. 1. No.2.15 1956, Astr. Circ. 170.13 Wachmann, A.A., 1935, Astron. Nachr. 255.11 Warner, B. and Nather, R.E., 1972, Monthly Not. R.A.S. 156.315 Wenzel, W., 1950, Mitt. Verand. Sterne Nr.125 1952, ibid. Nr.146 Wesselink, A.J., 1941, B.A.N. 9.217 Zissell, R., 1968, Astron. J. 73.696 Table 9 Photographic observations of CY Aqr J.D. m_pg J.D. m_pg J.D. m_pg J.D. m_pg 2428045 2428074 2432440 2433860 .3832 11.06 .3798 11.01 .4647 10.86 .5409 10.53 .3853 10.90 .3818 10.69 .4668 10.56 .5430 10.59 .3874 10.73 .3839 10.45 .4689 10.36 .5450 10.56 .3895 10.45 .3867 10.30 .4709 10.32 .5471 10.71 .3916 10.37 .3888 10.36 .4730 10.41 .5492 10.84 .3937 10.39 .4751 10.64 .5534 11.00 .3978 10.43 2428397 .4772 10.75 .5555 10.86 .3999 10.63 .5100 11.03 .4793 10.81 .5596 11.07 .4020 10.62 .5122 10.90 .4814 10.86 .5638 11.06 .4041 10.80 .5143 10.92 .4834 10.87 .5680 11.15 .4062 10.88 .5163 10.93 .4855 10.96 .5700 11.14 .4103 10.93 .5184 10.70 .4876 10.99 .5721 11.23 .4207 11.19 .5205 10.53 .4897 11.00 .5742 11.17 .4228 11.18 .5226 10.14 .4980 11.29 .5763 11.18 .4242 11.18 .5247 10.17 .5001 11.35 .4284 11.20 .5267 10.32 .5022 11.23 2433861 .4346 11.35 .5289 10.44 .5043 11.28 .4722 10.95 .4367 11.25 .5330 10.56 .5064 11.28 .4741 10.96 .4388 11.24 .5350 10.61 .5105 11.16 .4762 10.98 .4410 11.15 .5412 10.93 .5147 11.28 .4783 11.04 .4430 11.11 .5433 11.01 .5168 11.16 .4804 11.05 .4450 10.98 .5476 10.98 .5189 11.10 .4845 11.14 .5496 11.03 .5209 11.03 .4866 11.20 2428074 .5517 11.13 .5230 10.94 .4887 11.18 .3214 10.40 .5538 11.19 .4908 11.03 .3235 10.37 .5559 11.23 2433860 .4929 11.00 .3257 10.28 .4825 10.59 .4970 10.94 .3277 10.22 2432093 .4846 10.83 .4991 10.90 .3298 10.42 .3938 11.12 .4867 10.91 .5012 10.66 .3318 10.62 .3958 11.10 .4888 11.02 .5054 10.30 .3339 10.62 .3979 11.18 .4930 11.04 .5074 10.17 .3360 10.72 .4021 10.58 .4950 11.16 .5095 10.24 .3381 10.73 .4042 10.32 .4972 11.17 .5595 11.06 .3402 10.90 .4063 10.24 .5034 11.17 .5616 10.84 .3423 10.92 .4083 10.34 .5055 11.18 .5637 10.78 .3443 11.13 .4104 10.46 .5075 11.22 .5658 10.40 .3464 10.99 .4125 10.60 .5096 11.24 .5679 10.10 .3485 11.14 .4146 10.66 .5117 11.32 .5699 10.20 .3506 11.18 .4167 10.69 .5138 11.16 .5720 10.22 .3527 11.25 .4188 10.76 .5159 11.22 .5741 10.48 .3548 11.22 .4208 10.88 .5180 11.12 .5762 10.60 .3568 11.28 .4271 10.88 .5200 11.14 .5783 10.75 .3589 11.32 .4292 10.90 .5222 10.98 .5804 10.78 .3610 11.33 .4313 11.07 .5242 10.80 .3631 11.33 .4333 11.02 .5263 10.44 2433872 .3673 11.22 .4354 11.08 .5284 10.37 .5079 10.96 .3693 11.23 .5305 10.32 .5100 10.99 .3714 11.26 2432440 .5325 10.22 .5121 11.14 .3735 11.26 .4564 11.04 .5346 10.40 .5142 11.05 .3756 11.06 .4605 11.17 .5367 10.40 .5163 11.23 .3777 11.15 .4626 10.98 .5388 10.46 .5184 11.21 Table 9 (cont.) Photographic observations of CY Aqr J.D. m_pg J.D. m_pg J.D. m_pg J.D. m_pg 2433872 2433872 2434253 2434270 .5204 11.24 .5704 11.09 .5539 10.89 .3031 11.24 .5225 11.21 .5746 11.15 .5560 10.72 .3052 11.09 .5246 11.32 .5767 11.08 .5580 10.46 .3072 11.16 .5267 11.38 .5809 11.28 .5622 10.90 .3093 11.24 .5309 11.34 .5829 11.20 .5643 10.83 .3114 11.32 .5329 11.37 .5871 11.34 .5664 11.08 .3135 11.24 .5350 11.44 .5890 11.35 .5705 11.29 .3156 11.38 .5371 11.33 .5726 11.29 .3218 11.37 .5392 11.39 2434253 .5747 11.36 .3239 11.49 .5413 11.42 .5205 11.42 .5768 11.44 .3260 11.27 .5434 11.32 .5247 11.38 .5810 11.48 .3281 11.42 .5454 11.31 .5268 11.48 .5851 11.52 .3302 11.36 .5475 11.33 .5351 11.50 .5872 11.53 .3343 11.10 .5496 11.11 .5372 11.40 .5893 11.54 .3364 11.08 .5538 10.81 .5398 11.50 .5914 11.40 .3385 10.99 .5559 10.74 .5414 11.38 .3427 10.60 .5579 10.62 .5435 11.42 2434270 .3447 10.36 .5600 10.68 .5455 11.37 .2947 10.81 .3468 10.46 .5621 10.75 .5497 10.93 .2968 10.98 .3489 10.68 .5642 10.82 .5518 10.76 .2989 11.11 .3510 10.66 .5684 11.06 Table 10 Photoelectric yellow observations of CY Aqr J.D. Delta V J.D. Delta V J.D. Delta V J.D. Delta V 2441623 2441623 2441651 2444158 .2511 +1.067 .3053 +1.047 .2500 +1.024 .2792 +1.060 .2539 1.057 .3081 1.067 .2514 1.037 .2804 1.027 .2553 1.000 .3095 1.057 .2549 1.052 .2863 1.028 .2596 0.668 .3185 0.931 .2563 1.048 .2899 1.050 .2629 0.397 .3213 0.495 .2590 1.059 .2912 1.018 .2643 0.364 .3227 0.427 .2604 1.073 .2937 1.044 .2671 0.395 .3254 0.353 .2632 1.090 .2949 1.029 .2719 0.545 .3310 0.474 .2646 1.073 .2984 0.964 .2747 0.662 .3324 0.527 .2681 1.058 .3005 0.856 .2761 0.692 .3351 0.634 .2695 1.021 .3016 0.793 .2789 0.762 .3365 +0.650 .2736 0.937 .3037 0.516 .2803 0.788 .2903 0.635 .3047 0.392 .2831 0.905 2441651 .2945 0.752 .3071 0.368 .2845 0.915 .2292 +0.615 .2959 0.819 .3080 0.391 .2893 1.001 .2306 0.664 .2993 +0.888 .3105 0.443 .2921 1.035 .2333 0.743 .3121 0.451 .2935 1.052 .2347 0.780 2444158 .3148 0.560 .2977 1.036 .2375 0.854 .2711 +0.985 .3162 0.617 .3004 1.043 .2389 0.912 .2749 1.066 .3187 0.715 .3015 1.069 .2458 1.005 .2763 +1.040 .3200 +0.773 .3039 +1.089 .2472 +1.028 Table 11 Photoelectric blue observations of CY Aqr J.D. Delta B J.D. Delta B J.D. Delta B J.D. Delta B 2441623 2441623 2441651 2444158 .2490 +0.185 .3074 +0.180 .2507 +0.168 .2742 +0.152 .2504 0.178 .3089 0.170 .2542 0.178 .2756 0.150 .2532 0.160 .3122 0.179 .2556 0.181 .2784 0.192 .2546 0.123 .3164 0.119 .2583 0.190 .2800 0.214 .2574 +0.029 .3178 +0.096 .2597 0.184 .2823 0.209 .2589 -0.165 .3206 -0.287 .2639 0.204 .2835 0.219 .2622 0.555 .3220 0.398 .2674 0.200 .2869 0.214 .2636 0.615 .3303 0.559 .2688 0.198 .2893 0.206 .2664 0.621 .3317 0.491 .2729 +0.053 .2930 0.210 .2679 0.584 .3344 -0.358 .2896 -0.357 .2943 0.181 .2740 0.323 .2910 0.317 .2955 0.147 .2754 0.285 2441651 .2938 0.188 .2980 +0.089 .2782 0.174 .2285 -0.380 .2952 0.165 .3003 -0.024 .2796 0.136 .2299 0.306 .2979 -0.037 .3012 0.077 .2838 -0.015 .2326 0.190 .3000 +0.015 .3032 0.359 .2886 +0.120 .2368 0.051 .3042 0.506 .2914 0.149 .2382 -0.037 2444158 .3065 0.623 .2928 0.146 .2410 +0.049 .2641 -0.004 .3075 0.618 .2997 0.193 .2424 0.084 .2653 +0.019 .3141 0.415 .3011 0.202 .2451 0.112 .2680 0.047 .3155 0.319 .3032 0.173 .2465 0.136 .2704 0.084 .3180 0.210 .3046 +0.189 .2493 +0.144 .2716 +0.120 .3194 -0.196 Table 12 Photographic observations of EH Lib J.D. m_pg J.D. m_pg J.D. m_pg J.D. m_pg 2434487 2434488 2434516 2434516 .4294 10.14 .4294 9.44 .4013 10.09 .4534 9.45 .4349 9.94 .4349 9.52 .4034 9.94 .4555 9.44 .4405 9.89 .4377 9.60 .4055 10.00 .4576 9.54 .4433 9.75 .4405 9.67 .4075 10.01 .4596 9.57 .4460 9.73 .4433 9.73 .4096 9.94 .4617 9.54 .4488 9.53 .4460 9.77 .4117 9.98 .4638 9.63 .4516 9.44 .4488 9.84 .4159 9.99 .4659 9.62 .4544 9.42 .4516 9.80 .4180 10.07 .4680 9.70 .4572 9.42 .4544 9.85 .4305 10.11 .4700 9.76 .4599 9.56 .4572 9.97 .4346 10.02 .4770 9.81 .4627 9.63 .4627 9.94 .4388 10.00 .4791 9.80 .4655 9.95 .4409 9.98 .4812 9.86 2434488 .4683 10.07 .4430 9.78 .4832 9.86 .4127 9.99 .4710 10.02 .4450 9.70 .4853 9.89 .4155 9.81 .4471 9.61 .4895 9.99 .4210 9.59 2434516 .4492 9.48 .4916 10.05 .4238 9.37 .3992 10.00 .4513 9.48 .4999 10.09 .4266 9.35 Table 13 Photoelectric yellow observations of EH Lib J.D. Delta V J.D. Delta V J.D. Delta V J.D. Delta V 2441476 2442159 2442548 2442871 .4056 -0.190 .5056 -0.484 .3942 -0.273 .4839 -0.176 .4065 0.160 .5080 0.582 .4023 0.225 .4859 0.208 .4075 0.165 .5091 0.614 .4037 0.216 .4867 0.196 .4095 0.184 .5112 0.672 .4071 0.188 .4889 0.229 .4101 0.181 .5167 0.652 .4082 0.197 .4897 0.250 .4111 0.192 .5181 0.628 .4195 0.192 .4917 0.283 .4134 0.187 .5195 0.605 .4209 0.170 .4927 0.325 .4148 0.206 .5237 0.543 .4239 0.182 .4948 0.359 .4160 0.211 .5251 0.534 .4254 0.202 .4957 0.376 .4181 0.249 .5265 0.514 .4333 0.385 .4977 0.498 .4191 0.263 .5306 0.466 .4347 0.426 .4986 0.523 .4201 0.284 .5318 0.455 .4379 0.582 .5014 0.612 .4221 0.346 .5334 0.433 .4392 0.625 .5033 0.644 .4231 0.359 .5396 0.381 .4420 0.695 .5042 0.709 .4241 0.393 .5406 0.369 .4432 0.710 .5066 0.709 .4262 0.498 .5420 0.359 .4461 0.682 .5075 0.680 .4272 0.556 .5476 0.290 .4473 0.650 .5106 0.635 .4282 0.586 .5494 0.277 .4509 0.605 .5128 0.626 .4304 0.661 .5535 0.269 .4524 0.587 .5137 0.618 .4314 0.673 .5608 0.235 .4556 0.549 .5156 0.590 .4324 0.679 .5619 0.218 .4570 0.539 .5182 0.554 .4341 0.657 .5667 0.189 .4646 -0.438 .5191 0.525 .4363 0.667 .5677 0.179 .5210 0.494 .4382 0.638 .5688 0.173 2442871 .5218 -0.480 .4394 0.628 .5730 0.173 .4514 -0.316 .4404 0.605 .5744 0.165 .4525 0.302 2443957 .4426 0.597 .5751 0.176 .4546 0.285 .5650 -0.439 .4436 0.553 .5799 0.170 .4556 0.264 .5660 0.501 .4446 0.545 .5813 0.179 .4579 0.251 .5709 0.671 .4468 0.509 .5824 0.198 .4588 0.237 .5719 0.673 .4478 -0.499 .5858 0.255 .4610 0.272 .5733 0.688 .5876 0.275 .4620 0.234 .5747 0.692 2442159 .5890 0.310 .4639 0.213 .5768 0.671 .4882 -0.165 .5920 0.409 .4677 0.194 .5782 0.649 .4896 0.171 .5937 0.454 .4712 0.203 .5806 0.609 .4905 0.181 .5944 0.499 .4744 0.179 .5816 0.588 .4952 0.206 .5987 0.663 .4763 0.178 .5837 0.561 .4966 0.223 .5997 -0.692 .4773 0.188 .5851 0.539 .4980 0.265 .4794 0.167 .5879 0.498 .5035 0.425 2442548 .4804 -0.158 .5886 -0.504 .5049 -0.445 .3928 -0.286 Table 14 Photoelectric blue observations of EH Lib J.D. Delta B J.D. Delta B J.D. Delta B J.D. Delta B 2441476 2441476 2441476 2441476 .4051 -0.269 .4070 -0.289 .4100 -0.305 .4127 -0.312 .4062 -0.264 .4090 -0.283 .4106 -0.304 .4141 -0.310 Table 14 (cont.) Photoelectric blue observations of EH Lib J.D. Delta B J.D. Delta B J.D. Delta B J.D. Delta B 2441476 2442159 2442548 2442871 .4155 -0.315 .5174 -0.890 .4015 -0.344 .4863 -0.335 .4176 0.368 .5188 0.866 .4034 0.333 .4884 0.370 .4186 0.401 .5202 0.830 .4075 0.315 .4894 0.372 .4196 0.419 .5244 0.762 .4202 0.295 .4922 0.444 .4216 0.504 .5258 0.726 .4216 0.313 .4943 0.523 .4226 0.546 .5268 0.725 .4247 0.347 .4952 0.589 .4236 0.564 .5313 0.654 .4261 0.361 .4972 0.656 .4257 0.709 .5323 0.635 .4297 0.472 .4982 0.704 .4267 0.749 .5341 0.591 .4308 0.488 .5000 0.798 .4277 0.813 .5403 0.534 .4340 0.630 .5010 0.858 .4299 0.892 .5413 0.526 .4354 0.727 .5028 0.900 .4309 0.946 .5426 0.515 .4385 0.842 .5038 0.955 .4319 0.961 .5483 0.441 .4399 0.909 .5061 0.955 .4336 0.929 .5497 0.419 .4425 0.950 .5070 0.932 .4346 0.913 .5538 0.408 .4437 0.930 .5091 0.906 .4356 0.897 .5549 0.402 .4468 0.885 .5123 0.861 .4377 0.870 .5563 0.385 .4484 0.852 .5133 0.839 .4389 0.864 .5605 0.365 .4516 0.821 .5152 0.815 .4399 0.848 .5615 0.356 .4530 0.787 .5160 0.781 .4419 0.796 .5626 0.322 .4628 0.613 .5178 0.745 .4431 0.789 .5674 0.299 .4641 -0.617 .5205 0.709 .4441 0.736 .5681 0.285 .5214 -0.697 .4461 0.731 .5737 0.275 2442871 .4473 0.704 .5747 0.287 .4509 -0.435 2443957 .4483 0.686 .5758 0.292 .4520 0.429 .5643 -0.598 .4502 0.642 .5806 0.296 .4541 0.414 .5657 0.657 .4512 0.645 .5820 0.308 .4551 0.408 .5678 0.783 .4522 0.633 .5829 0.341 .4583 0.372 .5684 0.840 .4544 -0.565 .5869 0.394 .4605 0.391 .5705 0.926 .5883 0.428 .4615 0.363 .5712 0.964 2442159 .5893 0.466 .4635 0.353 .5730 0.966 .4889 -0.278 .5930 0.630 .4643 0.348 .5740 0.960 .4901 0.278 .5940 0.690 .4662 0.320 .5761 0.920 .4910 0.306 .5951 0.742 .4672 0.322 .5775 0.916 .4959 0.372 .5994 0.908 .4698 0.329 .5803 0.861 .4973 0.389 .6000 -0.953 .4707 0.309 .5809 0.846 .4983 0.428 .4759 0.308 .5830 0.830 .5042 0.662 2442548 .4768 0.288 .5844 0.801 .5052 0.683 .3924 -0.437 .4789 0.300 .5872 0.730 .5059 0.733 .3935 0.434 .4799 0.290 .5882 0.710 .5105 0.935 .3965 0.399 .4834 0.310 .5907 0.673 .5126 -0.934 .3979 -0.404 .4854 -0.327 .5914 -0.650 Table 15 Photoelectric yellow observations of DY Peg J.D. Delta V J.D. Delta V J.D. Delta V J.D. Delta V 2437164 2437164 2437164 2437164 .5129 +0.259 .5216 +0.261 .5247 +0.316 .5275 +0.383 Table 15 (cont.) Photoelectric yellow observations of DY Peg J.D. Delta V J.D. Delta V J.D. Delta V J.D. Delta V 2437164 2437167 2437178 2437178 .5342 +0.501 .3703 +0.371 .3696 +0.246 .4372 +0.416 .5372 0.557 .3733 0.421 .3701 0.233 .4379 0.366 .5400 0.586 .3759 0.505 .3707 0.225 .4393 0.276 .5466 0.671 .3821 0.581 .3714 0.209 .4400 0.272 .5493 0.679 .3846 0.587 .3721 0.195 .4406 0.254 .5521 0.707 .3866 0.607 .3740 0.180 .4413 0.209 .5581 0.718 .3892 0.645 .3747 0.185 .4420 0.205 .5605 0.756 .3946 0.703 .3754 0.184 .4427 0.189 .5632 0.736 .3967 0.719 .3761 0.195 .4434 0.186 .5691 0.730 .3991 0.718 .3768 0.215 .4448 0.175 .5726 0.689 .4033 0.732 .3775 0.228 .4455 0.165 .5816 0.446 .4054 0.728 .3796 0.252 .4462 0.168 .5844 0.335 .4073 0.728 .3803 0.258 .4469 0.179 .5872 +0.213 .4129 0.717 .3816 0.297 .4476 0.170 .4140 0.710 .3835 0.346 .4483 0.190 2437165 .4151 0.698 .3842 0.362 .4490 0.203 .4964 +0.656 .4173 0.675 .3849 0.390 .4504 0.234 .4971 0.665 .4185 0.645 .3861 0.413 .4511 0.258 .4978 0.679 .4195 0.633 .3868 0.425 .4518 0.278 .4985 0.675 .4207 0.619 .3875 0.436 .4525 0.303 .4992 0.704 .4233 0.527 .4122 0.714 .4532 0.305 .4999 0.697 .4243 0.462 .4129 0.722 .4539 0.319 .5006 0.705 .4253 0.405 .4136 0.708 .4546 0.318 .5021 0.715 .4263 0.376 .4143 0.696 .4560 0.354 .5028 0.721 .4293 0.209 .4150 0.696 .4566 0.358 .5035 0.713 .4303 0.189 .4157 0.701 .4573 0.362 .5042 0.706 .4315 0.183 .4171 0.697 .4580 0.381 .5049 0.719 .4326 0.177 .4178 0.718 .4587 0.408 .5056 0.722 .4337 0.174 .4185 0.710 .4601 0.446 .5062 0.721 .4347 0.190 .4192 0.700 .4614 0.464 .5076 0.734 .4373 0.240 .4199 0.704 .4621 0.495 .5082 0.724 .4384 0.261 .4206 0.697 .4628 0.480 .5089 0.747 .4394 0.289 .4213 0.707 .4635 0.503 .5096 0.743 .4404 +0.311 .4227 0.690 .4642 0.518 .5103 0.742 .4234 0.699 .4649 0.550 .5110 0.740 2437178 .4248 0.715 .4656 0.546 .5117 0.744 .3580 +0.665 .4255 0.717 .4670 0.557 .5138 0.730 .3587 0.663 .4261 0.722 .4677 0.570 .5145 0.738 .3594 0.643 .4268 0.717 .4684 0.601 .5152 0.726 .3601 0.617 .4282 0.695 .4691 0.610 .5159 0.736 .3608 0.604 .4289 0.680 .4698 0.611 .5166 0.725 .3615 0.583 .4296 0.668 .4712 0.624 .5173 0.725 .3622 0.563 .4303 0.665 .4726 0.617 .5187 0.713 .3636 0.476 .4310 0.636 .4733 0.633 .5199 0.714 .3643 0.450 .4317 0.639 .4740 0.642 .5207 0.685 .3650 0.414 .4324 0.590 .4747 0.647 .5214 0.671 .3657 0.397 .4337 0.572 .4754 0.638 .5221 0.665 .3664 0.358 .4344 0.540 .4761 0.637 .5228 +0.640 .3669 0.329 .4351 0.505 .4768 0.636 .3674 0.309 .4358 0.493 .4789 0.644 2437167 .3691 +0.257 .4365 +0.431 .4796 +0.648 Table 15 (cont.) Photoelectric yellow observations of DY Peg J.D. Delta V J.D. Delta V J.D. Delta V J.D. Delta V 2437178 2441535 2441984 2442279 .4802 +0.652 .5449 +0.734 .3623 +0.189 .4274 +0.271 .4816 0.681 .5482 0.748 .3641 0.208 .4281 0.280 .5516 0.736 .3648 0.221 .4288 0.307 2441535 .5530 0.715 .3668 0.226 .4295 +0.314 .4850 +0.679 .5540 0.717 .3675 0.236 .4857 0.642 .5565 0.675 .3693 0.296 2444113 .4881 0.596 .5572 +0.667 .3700 0.317 .4685 +0.586 .4888 0.588 .3728 0.379 .4695 0.589 .4902 0.542 2441963 .3735 0.416 .4728 0.614 .4926 0.473 .4117 +0.719 .3755 0.435 .4762 0.670 .4933 0.414 .4131 0.704 .3762 +0.455 .4812 0.689 .4943 0.374 .4154 0.686 .4822 0.743 .4961 0.275 .4168 0.650 2442279 .4842 0.744 .4971 0.243 .4193 0.605 .3921 +0.729 .4851 0.762 .4978 0.237 .4228 0.540 .3930 0.720 .4871 0.756 .4998 0.196 .4238 0.440 .3939 0.734 .4881 0.771 .5002 0.192 .4262 0.330 .3946 0.720 .4900 0.750 .5016 0.182 .4269 0.301 .3955 0.731 .4910 0.760 .5040 0.205 .4293 0.230 .3993 0.741 .4929 0.775 .5051 0.220 .4307 0.201 .4001 0.720 .4939 0.767 .5061 0.241 .4328 0.199 .4008 0.728 .4958 0.758 .5093 0.326 .4338 0.200 .4016 0.730 .4968 0.746 .5107 0.360 .4367 0.222 .4024 0.718 .4987 0.742 .5144 0.452 .4415 0.314 .4057 0.677 .4997 0.717 .5169 0.497 .4439 0.388 .4077 0.619 .5017 0.695 .5183 0.512 .4453 +0.403 .4084 0.612 .5026 0.689 .5190 0.521 .4091 0.577 .5046 0.648 .5214 0.556 2441984 .4120 0.477 .5075 0.574 .5221 0.564 .3400 +0.701 .4126 0.442 .5085 0.526 .5232 0.558 .3425 0.695 .4133 0.416 .5105 0.446 .5259 0.597 .3432 0.687 .4142 0.344 .5114 0.358 .5269 0.607 .3450 0.656 .4150 0.318 .5133 0.269 .5280 0.619 .3474 0.614 .4155 0.288 .5143 0.229 .5311 0.645 .3481 0.587 .4163 0.251 .5162 0.182 .5322 0.672 .3501 0.515 .4171 0.223 .5172 0.170 .5343 0.695 .3519 0.472 .4181 0.227 .5192 0.173 .5357 0.702 .3529 0.430 .4196 0.199 .5201 0.181 .5367 0.704 .3547 0.361 .4202 0.198 .5221 0.217 .5387 0.709 .3571 0.240 .4209 0.197 .5231 0.219 .5398 0.714 .3578 0.250 .4216 0.199 .5250 0.249 .5405 0.720 .3596 0.199 .4223 0.206 .5260 0.264 .5428 0.735 .3603 0.194 .4231 0.217 .5279 0.291 .5439 +0.738 .3616 +0.188 .4238 +0.222 .5289 +0.316 Table 16 Photoelectric blue observations of DY Peg J.D. Delta B J.D. Delta B J.D. Delta B J.D. Delta B 2437164 2437164 2437164 2437164 .5115 -0.018 .5143 -0.072 .5198 -0.084 .5230 -0.019 Table 16 (cont.) Photoelectric blue observations of DY Peg J.D. Delta B J.D. Delta B J.D. Delta B J.D. Delta B 2437164 2437165 2441535 2441963 .5328 +0.212 .5527 +0.216 .5002 -0.126 .4374 -0.076 .5358 0.281 .5012 0.133 .4411 +0.005 .5386 0.336 2437167 .5037 0.128 .4432 0.039 .5451 0.426 .3724 +0.135 .5044 0.120 .4446 0.090 .5507 0.481 .3745 0.179 .5058 0.091 .4471 +0.149 .5567 0.513 .3769 0.238 .5075 0.033 .5591 0.527 .3835 0.346 .5086 -0.005 2441984 .5622 0.529 .3856 0.371 .5100 +0.018 .3397 +0.508 .5677 0.501 .3877 0.417 .5120 0.066 .3404 0.502 .5707 0.484 .3936 0.453 .5127 0.090 .3422 0.483 .5740 0.458 .3957 0.466 .5141 0.124 .3429 0.455 .5802 0.226 .3979 0.484 .5176 0.226 .3453 0.433 .5830 +0.068 .4044 0.498 .5186 0.239 .3471 0.404 .5858 -0.055 .4064 0.507 .5211 0.270 .3478 0.370 .4121 0.491 .5218 0.286 .3491 0.307 2437165 .4146 0.495 .5225 0.310 .3498 0.293 .5249 +0.377 .4168 0.472 .5252 0.358 .3515 0.235 .5256 0.358 .4179 0.473 .5266 0.390 .3522 0.201 .5263 0.345 .4189 0.435 .5273 0.397 .3543 0.097 .5270 0.306 .4200 0.427 .5294 0.428 .3550 +0.048 .5284 0.257 .4228 0.305 .5308 0.418 .3568 -0.055 .5291 0.225 .4238 0.258 .5315 0.439 .3575 0.090 .5298 0.175 .4249 0.189 .5336 0.459 .3592 0.117 .5305 0.116 .4258 +0.102 .5350 0.474 .3599 0.127 .5312 0.071 .4279 -0.028 .5364 0.469 .3612 0.136 .5319 +0.014 .4288 0.094 .5384 0.488 .3619 0.142 .5332 -0.069 .4309 0.143 .5391 0.490 .3644 0.125 .5339 0.089 .4320 0.143 .5401 0.509 .3689 -0.011 .5346 0.110 .4332 0.146 .5464 0.511 .3696 +0.006 .5353 0.129 .4341 0.129 .5475 0.511 .3721 0.052 .5360 0.137 .4354 0.089 .5489 0.511 .3731 0.079 .5367 0.155 .4380 0.037 .5509 0.511 .3748 0.125 .5374 0.147 .4389 -0.021 .5523 0.499 .3758 +0.163 .5381 0.133 .4399 +0.007 .5537 0.503 .5395 0.138 .4410 0.010 .5558 0.477 2442279 .5402 0.133 .4422 +0.035 .5568 0.466 .3924 +0.503 .5409 0.121 .5579 +0.438 .3942 0.512 .5416 0.099 2441535 .3950 0.501 .5423 0.094 .4829 +0.469 2441963 .3959 0.525 .5430 0.085 .4843 0.438 .4110 +0.518 .4004 0.520 .5437 0.059 .4853 0.420 .4151 0.466 .4012 0.502 .5444 0.038 .4877 0.347 .4161 0.457 .4028 0.489 .5450 -0.021 .4884 0.305 .4186 0.381 .4061 0.451 .5457 +0.002 .4895 0.248 .4200 0.334 .4073 0.412 .5464 0.019 .4919 0.171 .4221 0.265 .4081 0.391 .5485 0.082 .4929 0.114 .4255 +0.058 .4088 0.350 .5492 0.112 .4940 +0.045 .4265 -0.031 .4095 0.330 .5499 0.124 .4954 -0.038 .4290 0.099 .4123 0.197 .5506 0.154 .4968 0.078 .4321 0.142 .4129 0.148 .5513 0.170 .4975 0.086 .4335 0.130 .4137 0.081 .5520 +0.183 .4995 -0.118 .4360 -0.107 .4147 +0.027 Table 16 (cont.) Photoelectric blue observations of DY Peg J.D. Delta B J.D. Delta B J.D. Delta B J.D. Delta B 2442279 2442279 2444113 2444113 .4157 -0.066 .4298 -0.005 .4895 +0.538 .5099 +0.198 .4159 0.075 .4905 0.534 .5109 +0.109 .4166 0.084 2444113 .4924 0.541 .5128 -0.014 .4174 0.109 .4680 +0.333 .4934 0.559 .5138 0.070 .4187 0.113 .4712 0.353 .4953 0.535 .5158 0.136 .4192 0.126 .4723 0.373 .4963 0.532 .5167 0.147 .4201 0.113 .4746 0.407 .4983 0.522 .5187 0.140 .4205 0.130 .4757 0.406 .4992 0.509 .5197 0.137 .4213 0.118 .4778 0.429 .5012 0.490 .5216 0.117 .4220 0.124 .4788 0.451 .5022 0.474 .5226 0.091 .4227 0.126 .4817 0.480 .5041 0.439 .5245 0.058 .4235 0.116 .4847 0.500 .5051 0.411 .5255 -0.026 .4242 0.088 .4866 0.516 .5070 0.366 .5274 +0.014 .4277 0.049 .4876 +0.522 .5080 +0.317 .5284 +0.033 .4284 -0.026