New and Improved Light Elements for Twenty Suspected Variable Stars

E. V. Kazarovets
Institute of Astronomy, Russian Academy of Sciences, Moscow, Russia

Received:   13.06.2024;   accepted:   17.09.2024
(E-mail for contact: helene@inasan.ru)

Comments:


1. = RAT J0728+2308. Min II = 20.76 zr. The sinusoidal type variability was suspected by Ramsay and Hakala (2005), no period.

2. = RAT J0739+2345. Min II = 16.20 zr. The variations with dips were suspected by Ramsay and Hakala (2005), no period.

3. = RAT J0740+2349. M – m = 0.45 P. The variability was suspected by Ramsay and Hakala (2005), no type or period.

4. = HD 62910 = HIP 037791 = WR 8 = LSS 731. Min II = 10.33 g; Min II – Min I = 0.45 P. O'Connell effect: Max II = 10.30 g. The variability with P = 114.6 d and without a type was suspected by Marchenko et al. (1998).

5. = IRAS 08083-3145 = CGCS 2095 = [W71b] 021-05. V = 12.09 – < 13.57. The ASAS-SN photometry in V and g bands, taken together, was used for period determination. Magnitudes in V were adjusted by +2 mag. The variability was discovered by Whitelock et al. (2006) with a type SR:, no period. The star was included in the ASAS-SN Variable Stars Database (Jayasinghe et al. 2018) with a type L without period.

6. = IRAS 08388-5116 = GCGSS 540 = He 4-51. V = 10.06 – 11.74. The variability was suspected by Van Eck et al. (2000). The star was included in the ASAS-SN Variable Stars Database (Jayasinghe et al. 2018) with a type L without period.

7. = HD 303004 = IRAS 10317-5845. Min II = 10.27 g, D = 0.05 P. In the reflection nebula GN 10.31.8 = BRAN 309D. The variability was suspected by Yudin and Evans (1998) according to observational data from literature.

8. = ASASSN-V J105201.92-621139.0. Min II = 15.63 V, D = 0.10 P. The variability was discovered by the ASAS-SN team (Jayasinghe et al. 2018) with the type EA and P = 4.0865791 d.

9. = 6771 in Chamaeleon I star-forming region. Min II = 14.58 g, D = 0.04 P. The short period variability was suspected by Carpenter et al. (2002).

10. = 12029 in Chamaeleon I star-forming region. Min II = 15.68 g. The short period variability was suspected by Carpenter et al. (2002).

11. = 19580 in Chamaeleon I star-forming region. Min II = 15.13 g, D = 0.12 P. The short period variability was suspected by Carpenter et al. (2002). The star is included in the ASAS-SN Variable Stars Database (Jayasinghe et al. 2018) with the type EW and P = 0.6857669 d.

12. = 22321 in Chamaeleon I star-forming region. Min II = 15.66 g. The short period variability was suspected by Carpenter et al. (2002). The star is included in the WISE catalogue (Chen et al. 2018) with the type EW and incorrect P = 0.3177814 d.

13. = 26688 in Chamaeleon I star-forming region. Min II = 15.20 g, D = 0.08 P. The variability with both short and long periods was suspected by Carpenter et al. (2002). The star is included in the WISE catalogue (Chen et al. 2018) with a type VAR and P = 1.9759512 d, as well as in the ASAS-SN Variable Stars Database (Jayasinghe et al. 2018) with the type EA and P = 3.951846 d.

14. = 29102 in Chamaeleon I star-forming region. The short period variability was suspected by Carpenter et al. (2002).

15. = ROTSE1 J112148.83+405938.0. Min II = 13.02 zr; zg = 13.29 – 13.47, Min II = 14.46 zg. The star was suspected by Kehoe et al. (2002) as pulsating variable candidate using NSVS photometric data (Woźniak et al. 2004), no period. Ferrante (2013) informed the VSX about the type EW and P = 0.371699 d for this variable. The object was included in the ZTF Catalogue of Variable Stars (Chen et al. 2020) with a type RSCVN and P = 0.1857474 d.

16. = Raf V102. Min II = 15.29 g. Twice shorter period and type DSCT are possible. Close fainter red companion (4" E-SE) and two brighter companions (15" N and 15" E). The variability was discovered by F. Hund in 2007 (RafV catalogue, 2005-2012), no type, period or magnitudes.

17. = UCAC4 211-079023. Min II = 14.75 V. The variability was discovered by Geffert et al. (2017), type SR without period. The star is included in the ASAS-SN Variable Stars Database (Jayasinghe et al. 2018) with the type EW and P = 24.4831 d.

18. = SDSS J144424.47+010901.5. M – m = 0.20 P; zr = 19.13 – 19.62. The ZTF photometry data combining zr and zg bands were used for period determination. The variability of RRAB type was suspected by Ivezić et al. (2000), no period. Sesar et al. (2017) confirmed type RRAB for the object PS1-3PI J144424.47+010901.5 and suggested incorrect P = 0.667676 d.

19. = Raf V123. Min II = 16.73 g. The variability was discovered by A. Paschke in 2007 (RafV catalogue, 2005-2012) with a type E, P = 0.3994 d, no magnitudes.

20. = TYC 3481-1550. Min II = 11.15, D = 0.08 P. The variability of this eclipsing star was reported by Hübscher (2017), no period and magnitudes.

Remarks:
I continue studying behavior of stars from my archive of suspected variables, accumulated since 1990s. I set a goal to create the Second Supplement to the NSV catalogue (Kazarovets et al., 2022) of the archival stars before obtaining variability confirmation using CCD photometric data from contemporary sky surveys. For each of the archival stars, I acquire accurate positions and identifications with different catalogues, and I do my best to determine variability types and light elements. Then I select stars confirmed as variable by myself in order to transfer them to the General Catalogue of Variable Stars (GCVS) (Samus et al., 2017) via the next Name-Lists. Today 41% of 1000 studied stars comply with GCVS rules. In the current paper, I present 20 stars from confirmed 415 stars that proved to be variable. The study of the presented variables was made using the publicly available electronic archives of CCD observations of the Sky Patrol All-Sky Automated Survey for Supernovae (ASAS-SN) project (Shappee et al., 2014; Kochanek et al., 2017) and the Zwicky Transient Facility (ZTF) photometric data (Bellm et al., 2019; Masci et al., 2019) via the SNAD ZTF viewer (Malanchev et al., 2023). To find periods, I applied the WinEfk software provided by Dr. V.P. Goranskij and the online light curve analysis tool developed by Dr. K.V. Sokolovsky. The coordinates of the stars were drawn from the Gaia DR3 catalogue (Gaia Collaboration, 2023).

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