OGLE Pre-Eruption Observations of V572 Velorum Reveal Dwarf Nova Outbursts

ATel #17253; K. Ulaczyk (Warwick), P. Mroz, A. Udalski (Warsaw)
on 28 Jun 2025; 06:25 UT
Credential Certification: Przemek Mroz (pmroz@astrouw.edu.pl)

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We report the pre-eruption photometric observations of the probable nova V572 Velorum (PNV J10251200-5331109; CBET #5574, ATel #17252). The nova is located in the field GD2273, which has been regularly observed by the Optical Gravitational Lensing Experiment (OGLE) since 2017. The position of the nova is consistent with that of a faint star, GD2273.05.2400, listed in the OGLE database. Its equatorial coordinates (J2000) are RA = 10:25:13.90, Dec. = -53:31:19.3.
The historical activity was originally detected in Gravitational-wave Optical Transient Observer (GOTO, Steeghs et al. 2022) survey data. The last detection before nova discovery was at 2025-06-19T09:53:00 with a magnitude L=16.65 +/- 0.02 mag. The L-band is approximately g+r combined, and no colour-term corrections were applied. At least 5 outburst occurrences were also detected in ATLAS data (Tonry et al. 2018).
The archival OGLE observations reveal that the star experienced multiple outbursts during the years 2017-2024, indicating its classification as a dwarf nova. We tentatively classify it as an SU UMa-type object due to the presence of both long (lasting more than 13 days) and short (lasting 3-4 days) outbursts.
The progenitor reached a maximum I-band brightness of I = 17.169 +/- 0.032 mag during its long outburst in February 2025. The star was not detected during quiescence, and we estimate it was fainter than I = 20.1 mag between its outbursts (3 sigma upper limit).
Classical novae originating from dwarf nova progenitors are extremely rare. The known examples include V1213 Cen (Mroz et al. 2016) and V392 Per (Murphy-Glaysher et al. 2022).
Given the preliminary detection of gamma rays by the Fermi Gamma-ray Space Telescope (ATel #17252) and a dwarf nova progenitor, we strongly encourage follow-up observations.