2026A&A...707A..25B


Query : 2026A&A...707A..25B

2026A&A...707A..25B - Astronomy and Astrophysics, volume 707A25 (2026/3-1)

The optical photometric and spectroscopic periodicities of the cataclysmic variable SRGt 062340.2-265751.

BRINK J., BUCKLEY D.A.H., VERESVARSKA M., SCHWOPE A.D., GROOT P.J., THORSTENSEN J.R., CUNEO V.A., POTTER S.B., TITUS N., EGBO D., LEES R., MOGAWANA O. and VAN DYK A.

Abstract (from CDS):

Context. We report on optical spectroscopic and photometric follow-up observations of the eROSITA discovered transient SRGt 062340.2-265751 and show that it displays the characteristics of a nova-like cataclysmic variable (CV), with possible indications of being a magnetic system.
Aims. We try to put better constraints on the classification of SRGt 062340.2-265751 using optical time-resolved spectroscopic and photometric observations to find any periodicities in the system. From these periodicities we can classify the CV sub-type that it belongs to.
Methods. Time-resolved photometric and spectroscopic observations were obtained at the South African Astronomical Observatory (SAAO), using the 1.9 m and the two 1.0 m telescopes. High-resolution spectra were also taken using the Southern African Large Telescope (SALT), to study the morphology of the emission lines seen in the system. Archival photometric data was also analysed in this study, including ASAS-SN, CRTS, and TESS observations.
Results. Spectroscopic observations revealed a very low amplitude, K ∼ 14 km s–1, in the radial velocity of the Hβ and Hγ emission lines, suggesting that the system is likely observed at a low inclination angle. High-speed photometric observations revealed highly stochastic variability, characteristic of many magnetic cataclysmic variable systems. A probable 3.645 ± 0.006 hour orbital period was found by applying Lomb-Scargle period analysis to the Hβ and Hγ emission line radial velocities. A 24.905 ± 0.065 min period was found from photometric observations, which we associate with the white dwarf spin. However, it was also found that the photometry revealed multiple periodicities from night to night. TESS observations in three sectors did not reveal any of the periodicities found from ground-based observations, but did show a prominent period in only one sector, which might be attributed to a positive superhump period. These multiple periodicities as well as the He IIλ4686 and Bowen blend emission lines seen in the spectra indicate that SRGt 062340.2-265751 is likely a nova-like CV, and might belong to the VY Scl sub-type.

Abstract Copyright: © The Authors 2026

Journal keyword(s): binaries: close - novae, cataclysmic variables - white dwarfs - stars: winds - outflows

Simbad objects: 12

goto Full paper

goto View the references in ADS

Number of rows : 12
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2026
#notes
1 V* BB Dor CV* 05 29 28.5849988224 -58 54 46.184462928 13.68 15.57 15.52 14.83   ~ 53 0
2 V* TX Col CV* 05 43 20.16864 -41 01 54.2856         14.541 ~ 167 0
3 UCAC2 20781392 * 06 23 34.4441628696 -26 58 30.645864012   13.019 12.080 12.01 11.11 ~ 6 0
4 1RXS J062339.8-265744 X 06 23 39.8 -26 57 44           ~ 5 0
5 UCAC4 316-011308 CV* 06 23 40.0348994640 -26 57 50.783570064   12.719 12.724 12.783   ~ 14 0
6 1RXS J071404.0+700413 CV* 07 14 04.6544846424 +70 04 18.400751472   11.86 11.83 11.71   ~ 21 0
7 V* DW UMa CV* 10 33 52.8751411128 +58 46 54.717259044   14.33   14.33 14.35 ~ 254 0
8 V* UX UMa CV* 13 36 40.9531256400 +51 54 49.423353228   12.78 13.26     sdOB 556 0
9 V* MV Lyr CV* 19 07 16.2886463256 +44 01 07.869892008   13.040 12.920 12.489 12.578 M5Ve 307 0
10 V* UU Aqr CV* 22 09 05.7613016472 -03 46 17.688853416   13.998 13.919 13.735   ~ 153 0
11 V* RZ Gru CV* 22 47 12.0065854128 -42 44 38.720903280   12.39 12.04     B6 52 0
12 GD 1662 CV* 23 29 00.4713595416 -29 46 45.980660100   13.054 12.980 13.099   OBe 191 0

To bookmark this query, right click on this link: simbad:objects in 2026A&A...707A..25B and select 'bookmark this link' or equivalent in the popup menu