Peremennye Zvezdy ( Variable Stars) 40, No. 5, 2020 Received 14 September; accepted 25 September.
DOI: 10.24411/2221-0474-2020-10006 BVIc CCD Observations of the RR Lyrae variable T Men
L.N. Berdnikov1, A.Yu. Kniazev1'2'3, A.K. Dambis1, V.V. Kravtsov1
1 Sternberg Astronomical Institute, Moscow State University, Universitetskij pr. 13, Moscow 119992, Russia
2 South African Astronomical Observatory, P.O. Box 9, Observatory, Cape Town, 7935 South Africa
3 Southern African Large Telescope Foundation, P.O. Box 9, Observatory, Cape Town, 7935 South Africa
We present 3296 magnitude measurements in the B, V, and Ic filters acquired for the RR Lyrae star T Men.
1 Introduction
The high luminosity and large age of RR Lyrae variables make them ideal distance indicators and tracers for studies of the structure and kinematics of old Galactic subsystems, the halo and the thick disk. However, by 2011, the number of RR Lyrae variables with precise photometry in the extended solar neighborhood was rather limited - a total of about 300 stars (Dambis, 2009). This is why we started a program aimed at obtaining photometric observations for the greatest possible number of RR Lyraes. We published the first results of our photometric observations in our previous paper (Berdnikov et al., 2012), where we suspected the presence of Blazhko effect (Blazhko, 1907) in several stars, including T Men.
We continued to observe T Men, and here we present the results of our photometry.
2 Observational data
We performed CCD observations of T Men during three observing runs (in the JD 2455896
- 56676 range) with the 76-cm telescope of the South African Astronomical Observatory (SAAO) using a SBIG CCD ST-10XME camera equipped with BVIc-band filters of the Kron-Cousins photometric system (Cousins, 1976). A description of the observing data reduction technique can be found in our previous paper (Berdnikov, 2012). We acquired a total of 2722 CCD frames with photometric errors close to 0.01 mag.
We also used the Las Cumbres Observatory Global Telescope (LCOGT) Network (Brown, 2013) to acquire 574 CCD BVIc frames during the time interval JD 2456635
- 56687. We reduce LCOGT observations by performing differential photometry relative to secondary standards whose magnitudes we determined based on observations made in SAAO; the photometric errors of these observations are close to 0.02 mag.
All observations are available in a text file in the html version of the paper.
The light curves are shown in Fig. 1, where the enhanced scatter of points supports the presence of Blazhko effect. We plan to use our data to search for the Blazhko effect period of T Men.
On the base of our observations we constructed the B-, V- and Ic-band template curves which are presented in Table 1 and Fig. 2; together with them we present the g'-band template curve, based on observations from the ASAS-SN catalog (Jayasinghe et al., 2019). Table 1 lists the B-, g'-, V- and Ic-band magnitudes of T Men at phases from 0 to 0.995 with a step of 0.005.
We plan to use these templates to study the behavior of pulsating period of T Men.
Acknowledgments: This work was supported by the Russian Foundation for Basic Research (project nos. 18-02-00890 and 19-02-00611).
References:
Berdnikov, L.N., Kniazev, A.Yu., Sefako, R., et al., 2011, Astron. Rep., 55, 816 Blazhko, S., 1907, Astron. Nachr, 175, 325
Brown, T.M., Baliber, N., Bianco, F.B., et al., 2013 Publ. Astron. Soc. Pacif, 125, 1031 Cousins, A.W.J., 1976, Mem. RAS, 81, 25
Jayasinghe T., Stanek K.Z., Kochanek C.S., et al.), 2019, Mon. Not. Roy. Astron. Soc., 485, 961
TMen
Max JDH = 2456287.4765 + 0.4097892 E
0.0 0.5 1.0
Phase
Figure 1. BVIc phased light curves of the RR Lyrae type star T Men. The enhanced scatter is due to the Blazhko effect.
Phase
Figure 2. The B-, g'-, V- and Ic-band template curves of T Men.
Table 1. B-, g'-, V- and Iq -band template curves of T Men
Phase В g' У Ic Phase В g' У Ic
0.000 13.255 13.096 13.074 12.824 0.500 14.280 14.016 13.856 13.262
0.005 13.256 13.097 13.075 12.824 0.505 14.283 14.018 13.859 13.263
0.010 13.260 13.100 13.078 12.826 0.510 14.285 14.019 13.863 13.264
0.015 13.266 13.104 13.082 12.829 0.515 14.287 14.020 13.865 13.265
0.020 13.273 13.110 13.088 12.833 0.520 14.289 14.021 13.868 13.266
0.025 13.283 13.117 13.096 12.838 0.525 14.292 14.022 13.870 13.267
0.030 13.293 13.125 13.104 12.843 0.530 14.294 14.023 13.871 13.268
0.035 13.305 13.134 13.113 12.849 0.535 14.296 14.024 13.871 13.269
0.040 13.317 13.144 13.123 12.856 0.540 14.298 14.024 13.871 13.271
0.045 13.330 13.154 13.133 12.863 0.545 14.299 14.024 13.870 13.272
0.050 13.344 13.165 13.143 12.870 0.550 14.299 14.024 13.868 13.274
0.055 13.358 13.177 13.153 12.876 0.555 14.299 14.024 13.867 13.275
0.060 13.372 13.189 13.164 12.882 0.560 14.297 14.023 13.865 13.277
0.065 13.386 13.201 13.175 12.889 0.565 14.295 14.023 13.863 13.278
0.070 13.400 13.214 13.185 12.894 0.570 14.292 14.023 13.861 13.279
0.075 13.414 13.227 13.195 12.900 0.575 14.290 14.022 13.859 13.279
0.080 13.428 13.240 13.205 12.905 0.580 14.287 14.022 13.858 13.280
0.085 13.442 13.253 13.215 12.910 0.585 14.284 14.021 13.858 13.280
0.090 13.456 13.267 13.226 12.915 0.590 14.283 14.021 13.858 13.279
0.095 13.469 13.281 13.236 12.920 0.595 14.281 14.021 13.859 13.278
0.100 13.483 13.295 13.246 12.925 0.600 14.281 14.021 13.860 13.278
0.105 13.496 13.309 13.257 12.930 0.605 14.282 14.021 13.862 13.277
0.110 13.510 13.323 13.268 12.935 0.610 14.284 14.021 13.864 13.276
0.115 13.524 13.337 13.279 12.940 0.615 14.286 14.022 13.866 13.275
0.120 13.539 13.351 13.291 12.946 0.620 14.289 14.022 13.868 13.275
0.125 13.554 13.365 13.303 12.952 0.625 14.292 14.023 13.870 13.275
0.130 13.569 13.380 13.314 12.958 0.630 14.295 14.024 13.871 13.275
0.135 13.585 13.394 13.326 12.965 0.635 14.297 14.025 13.872 13.276
0.140 13.601 13.408 13.338 12.971 0.640 14.298 14.026 13.871 13.278
0.145 13.616 13.422 13.349 12.977 0.645 14.298 14.027 13.870 13.279
0.150 13.632 13.436 13.360 12.984 0.650 14.298 14.028 13.869 13.281
0.155 13.647 13.450 13.370 12.990 0.655 14.297 14.030 13.866 13.283
0.160 13.662 13.464 13.380 12.996 0.660 14.295 14.031 13.864 13.285
0.165 13.677 13.478 13.391 13.002 0.665 14.293 14.032 13.862 13.287
0.170 13.691 13.492 13.401 13.008 0.670 14.292 14.033 13.861 13.289
0.175 13.705 13.506 13.411 13.014 0.675 14.290 14.035 13.860 13.291
0.180 13.719 13.520 13.422 13.019 0.680 14.289 14.036 13.861 13.292
0.185 13.733 13.533 13.433 13.025 0.685 14.288 14.037 13.863 13.294
0.190 13.747 13.547 13.444 13.030 0.690 14.288 14.039 13.865 13.296
0.195 13.761 13.561 13.455 13.036 0.695 14.288 14.041 13.869 13.297
0.200 13.776 13.574 13.467 13.041 0.700 14.290 14.043 13.873 13.300
0.205 13.791 13.587 13.478 13.047 0.705 14.291 14.045 13.878 13.302
0.210 13.806 13.601 13.489 13.052 0.710 14.293 14.048 13.882 13.306
0.215 13.821 13.614 13.500 13.058 0.715 14.295 14.051 13.887 13.310
0.220 13.836 13.627 13.510 13.063 0.720 14.297 14.055 13.891 13.314
0.225 13.851 13.639 13.521 13.068 0.725 14.300 14.060 13.895 13.319
0.230 13.866 13.652 13.530 13.074 0.730 14.304 14.065 13.899 13.325
0.235 13.880 13.665 13.540 13.079 0.735 14.309 14.071 13.904 13.331
0.240 13.893 13.677 13.549 13.084 0.740 14.314 14.077 13.909 13.338
0.245 13.906 13.689 13.558 13.089 0.745 14.320 14.084 13.915 13.344
0.250 13.919 13.700 13.567 13.093 0.750 14.328 14.092 13.921 13.350
0.255 13.931 13.712 13.577 13.098 0.755 14.337 14.100 13.928 13.355
0.260 13.943 13.723 13.586 13.102 0.760 14.346 14.108 13.936 13.360
0.265 13.954 13.734 13.596 13.107 0.765 14.356 14.117 13.943 13.364
0.270 13.966 13.745 13.605 13.111 0.770 14.366 14.125 13.950 13.368
0.275 13.977 13.755 13.615 13.115 0.775 14.375 14.134 13.957 13.371
0.280 13.989 13.765 13.624 13.120 0.780 14.383 14.141 13.963 13.373
0.285 14.000 13.775 13.633 13.124 0.785 14.389 14.148 13.968 13.375
0.290 14.012 13.784 13.642 13.128 0.790 14.394 14.154 13.972 13.377
0.295 14.023 13.794 13.651 13.132 0.795 14.396 14.158 13.974 13.378
0.300 14.034 13.803 13.659 13.137 0.800 14.397 14.160 13.975 13.379
Table 1. Continued.
Phase B g' V Ic Phase B g' V Ic
0.305 14.045 13.811 13.668 13.141 0.805 14.396 14.160 13.976 13.380
0.310 14.056 13.820 13.677 13.145 0.810 14.394 14.158 13.975 13.380
0.315 14.066 13.828 13.686 13.149 0.815 14.391 14.153 13.973 13.380
0.320 14.075 13.837 13.695 13.153 0.820 14.387 14.146 13.970 13.380
0.325 14.085 13.845 13.703 13.157 0.825 14.382 14.135 13.967 13.377
0.330 14.094 13.853 13.711 13.161 0.830 14.375 14.121 13.962 13.373
0.335 14.103 13.861 13.719 13.165 0.835 14.368 14.104 13.955 13.367
0.340 14.111 13.869 13.726 13.168 0.840 14.357 14.083 13.945 13.359
0.345 14.120 13.876 13.733 13.172 0.845 14.344 14.058 13.932 13.347
0.350 14.129 13.884 13.739 13.175 0.850 14.326 14.031 13.916 13.333
0.355 14.138 13.891 13.745 13.179 0.855 14.302 13.999 13.895 13.315
0.360 14.147 13.898 13.750 13.182 0.860 14.272 13.965 13.869 13.294
0.365 14.156 13.906 13.755 13.186 0.865 14.235 13.928 13.838 13.270
0.370 14.165 13.913 13.761 13.189 0.870 14.191 13.889 13.802 13.243
0.375 14.173 13.919 13.766 13.192 0.875 14.140 13.847 13.761 13.214
0.380 14.182 13.926 13.771 13.195 0.880 14.082 13.803 13.717 13.184
0.385 14.190 13.932 13.776 13.198 0.885 14.019 13.757 13.669 13.153
0.390 14.197 13.938 13.781 13.201 0.890 13.953 13.711 13.618 13.122
0.395 14.204 13.944 13.786 13.205 0.895 13.885 13.664 13.566 13.091
0.400 14.210 13.950 13.791 13.207 0.900 13.817 13.617 13.514 13.061
0.405 14.215 13.955 13.796 13.210 0.905 13.751 13.570 13.464 13.033
0.410 14.220 13.960 13.800 13.213 0.910 13.688 13.524 13.415 13.007
0.415 14.224 13.965 13.805 13.216 0.915 13.630 13.479 13.370 12.982
0.420 14.228 13.969 13.809 13.219 0.920 13.578 13.435 13.328 12.961
0.425 14.231 13.974 13.814 13.221 0.925 13.531 13.393 13.290 12.941
0.430 14.235 13.978 13.818 13.224 0.930 13.489 13.354 13.256 12.924
0.435 14.239 13.981 13.822 13.227 0.935 13.453 13.316 13.227 12.909
0.440 14.243 13.985 13.826 13.230 0.940 13.422 13.282 13.202 12.896
0.445 14.247 13.988 13.829 13.233 0.945 13.395 13.250 13.180 12.884
0.450 14.250 13.992 13.833 13.237 0.950 13.371 13.222 13.161 12.874
0.455 14.255 13.995 13.835 13.240 0.955 13.350 13.196 13.144 12.865
0.460 14.259 13.998 13.838 13.243 0.960 13.331 13.174 13.130 12.857
0.465 14.262 14.000 13.840 13.246 0.965 13.314 13.154 13.118 12.850
0.470 14.266 14.003 13.842 13.249 0.970 13.300 13.138 13.107 12.843
0.475 14.269 14.005 13.844 13.252 0.975 13.286 13.125 13.097 12.837
0.480 14.272 14.008 13.846 13.254 0.980 13.275 13.114 13.089 12.833
0.485 14.274 14.010 13.848 13.257 0.985 13.267 13.106 13.083 12.829
0.490 14.276 14.012 13.851 13.259 0.990 13.260 13.101 13.078 12.826
0.495 14.278 14.014 13.853 13.260 0.995 13.256 13.097 13.075 12.824