Optical photometry of the CV LAMOST J015016.17+375618.9 after X-ray brightening
ATel #16897; Peter Garnavich (Notre Dame)
on 9 Nov 2024; 14:48 UT
Credential Certification: Peter Garnavich (pgarnavi@nd.edu)
Subjects: Optical, Cataclysmic Variable
The apparent increase in X-ray luminosity of LAMOST-J015016.17+375618.9(J015016 hereafter; ATEL #16896) detected by the Einstein Probe, prompted optical photometric observations with the 0.8-m Sarah L. Krizmanich telescope starting at 2024 Nov. 8.596 (UT). Unfiltered time-series photometry over 2-hours was obtained with a 5.9s cadence.
Comparison with a nearby R=13.1 mag star from the APASS catalog, the average brightness of J015016 was
CR=15.4 mag. Large brightness fluctuations and a slow fading of 0.2 mag were detected over the 2-hours of the observation.
A Lomb-Scargle periodogram of the data revealed a strong signal at 37.1 cycles/day (39 min period) with a full amplitude of 0.4 mag. Variability on time-scales of 10 to 12 minutes with a full amplitude of 0.2 mag are also seen.
The enhanced optical brightness of J015016 suggests that it is undergoing a dwarf nova outburst. The variations are significantly shorter than the orbital period of 0.148 days (Thorstensen, Alper, & Weil 2016, AJ, 152, 226), and could be strong quasi-periodic oscillations (QPOs).
