ASAS-SN Discovery of an Unprecedented >1.5 Magnitude Optical Flare from QSO B0346-279
ATel #11337; P. Vallely, K. Z. Stanek, C. S. Kochanek, J. V. Shields, T. A. Thompson (Ohio State), B. J. Shappee (IfA-Hawaii), T. W.-S. Holoien (Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), D. Bersier (LJMU), Subo Dong, S. Bose, Ping Chen (KIAA-PKU), M. Stritzinger (Aarhus)
on 22 Feb 2018; 21:37 UT
Credential Certification: Krzysztof Stanek (firstname.lastname@example.org)
Subjects: Optical, Quasar
During the ongoing All Sky Automated Survey for SuperNovae
(ASAS-SN, Shappee et
al. 2014), using data from the quadruple 14-cm "Brutus" telescope
in Haleakala, Hawaii, the quadruple 14-cm "Leavitt" telescope in Fort
Davis, Texas, the quadruple 14-cm "Payne-Gaposchkin" telescope in
Sutherland, South Africa, and the quadruple 14-cm "Cassius" and
"Paczynski" telescopes in Cerro Tololo, Chile, we have discovered an
unprecedented optical brightening of QSO B0346-279 (z~0.9874).
QSO B0346-279, while optically
variable in CRTS data, was never seen to be brighter than
V~17.5. Its g-band magnitude in Gaia data is g=18.7 and its PS1
brightness is g=19.8. In archival
ASAS-SN data going back to February 2013 it is not seen to be
brighter than V~17 until the onset of this flaring event. QSO
B0346-279 reached a V-band magnitude of V=15.5 on UT 2018-02-21.08
(g=16.4 on UT 2018-02-17.09), decaying to V=15.8 on UT
2018-02-22.07. Such a dramatic brightening is unprecedented for this
object. V and g-band photometric observations of this ongoing event
are shown here.
Follow-up observations are encouraged.
We would like to thank Las Cumbres Observatory and its staff for
their continued support of ASAS-SN. ASAS-SN is funded in part by the
Gordon and Betty Moore Foundation through grant GBMF5490 to the Ohio
State University, NSF grant AST-1515927, the Mt. Cuba Astronomical
Foundation, the Center for Cosmology and AstroParticle Physics (CCAPP)
at OSU, the Chinese Academy of Sciences South America Center for
Astronomy (CASSACA), and the Villum Fonden (Denmark).