Spectroscopic follow up of the slowly rising, likely Galactic nova Gaia22alz (AT2022bpq)
ATel #15395; E. Aydi, J. Strader, L. Chomiuk, K. V. Sokolovsky, A. Kawash (MSU), J. Brink, D. A. H. Buckley (SAAO/UCT), M. Orio (UoW/INAF), J. Mikolajewska (NCAC), K. Z. Stanek, C. S. Kochanek (OSU), and B. J. Shappee (Univ. of Hawaii)
on 23 May 2022; 20:14 UT
Credential Certification: Elias Aydi (aydielia@msu.edu)
Subjects: Optical, Binary, Cataclysmic Variable, Nova, Star, Transient
We report on spectroscopic follow up of the slowly rising Galactic optical transient Gaia22alz (AT2022bpq), which was discovered by Gaia on 2022-02-04.2UT (https://www.wis-tns.org/object/2022bpq), and has been rising for 118 days. Based on photometry from the All-Sky Automated Survey for SNe (ASAS-SN; Shappee et al. 2014, ApJ, 788, 48S and Kochanek et al. 2017PASP, 129, 4502) the transient is now at g = 12.5 mag, implying a current minimum outburst amplitude of 6.4 mag.
Earlier follow-up by Aydi et al. (ATel #15355) reported the development of P Cygni profiles in the Balmer and He I lines that dominate the spectrum. We have obtained a series of low-, medium-, and high-resolution optical spectra on 2022-04-30, 05-08, 05-11, and 05-22 using the Goodman spectrograph (Clemens et al. 2004, SPIE, 5492, 331) on the 4.1-m SOAR telescope (Cerro Pachon, Chile) and the High Resolution Spectrograph (HRS; Crause et al. 2014, Proc. SPIE, 91476) on the 11-m Southern African Large Telescope as part of the SALT Large Science Program on Transients. The spectra show further development with the emergence of Fe II and O I P Cygni profiles and fading He I lines. The P Cygni absorption profiles are now at blueshifted velocities of 1200-1300 km/s, compared to 1700-1800 km/s a month ago (see ATel #15355). The overall spectra resemble that of a classical nova before optical peak, however the slow rise of the outburst is intriguing. Follow up observations in all bands are highly encouraged.
The latest ASAS-SN sky patrol light curve can be found here: https://asas-sn.osu.edu/sky-patrol/coordinate/0e3dcbfd-4d95-4643-9a04-e3bbf87f4740
This ATel is based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of MCTIC/LNA, the U.S. NSF's NOAO, UNC, and MSU
