ASAS-SN Discovery of ASASSN-18dw, a 4+ Magnitudes Stellar Outburst Towards Orion
ATel #11359; K. Z. Stanek, C. S. Kochanek, J. V. Shields, T. A. Thompson (OSU), B. J. Shappee (IfA-Hawaii), T. W.-S. Holoien (Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), Subo Dong (KIAA-PKU), M. Stritzinger (Aarhus)
on 26 Feb 2018; 17:30 UT
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Credential Certification: Krzysztof Stanek (email@example.com)
Subjects: Optical, Transient
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN,
et al. 2014), using data from 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
"Paczynski" telescope in Cerro Tololo, Chile, we detect a bright,
rapidly raising transient source
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. g mag
ASASSN-18dw 06:02:04.77 -12:19:50.8 2018-02-25.14 14.3
ASASSN-18dw was discovered in images obtained on UT 2018-02-25.14
at g~14.3. We also detect this source on UT 2018-02-24.087 (g~15.8),
UT 2018-02-24.169 (g~15.3), UT 2018-02-25.88 (g~13.8) and UT
2018-02-26.20 (g~13.6). We do not detect (g>17.6) this object in
g-band subtracted images taken on UT 2018-02-23.18 and before. The
position of ASASSN-18dw matches to a
reddish PS1 g=18.6, r=17.8 source
in the vicinity of the Orion star forming region (there are also
numerous Vizier matches to other catalogs, including Gaia and GALEX).
We have retrieved image subtraction photometry time series at the
location of ASASSN-18dw in both V-band and g-band. No previous
outbursts or variability are detected at the position of ASASSN-18dw
since ASAS-SN started observing this location in October 2013.
Follow-up observations, especially spectroscopy, are strongly 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).