VVV-WIT-01: highly obscured classical nova or protostellar collision?

Journal
Date Issued
2020
Author(s)
Lucas, P. W.
•
Minniti, D.
•
Kamble, A.
•
Kaplan, D. L.
•
Cross, N.
•
Dekany, I.
•
Ivanov, V. D.
•
Kurtev, R.
•
Saito, R. K.
•
Smith, L. C.
•
Catelan, M.
•
•
Toledo, I.
•
Hempel, M.
•
Thompson, M. A.
•
Contreras Peña, C.
•
Forbrich, J.
•
Krause, M.
•
Dale, J.
•
Borissova, J.
•
Emerson, J.
DOI
Abstract
A search of the first Data Release of the VISTA Variables in the Via Lactea (VVV) Survey discovered the exceptionally red transient VVV-WIT-01 (H - Ks = 5.2). It peaked before March 2010, then faded by ˜9.5 mag over the following 2 yr. The 1.6-22 μm spectral energy distribution in March 2010 was well fit by a highly obscured blackbody with T ˜ 1000 K and A_{K_s} ˜ 6.6 mag. The source is projected against the Infrared Dark Cloud (IRDC) SDC G331.062-0.294. The chance projection probability is small for any single event (p ≈ 0.01-0.02), which suggests a physical association, e.g. a collision between low mass protostars. However, blackbody emission at T ˜ 1000 K is common in classical novae (especially CO novae) at the infrared peak in the light curve due to condensation of dust ˜30-60 d after the explosion. Radio follow-up with the Australia Telescope Compact Array detected a fading continuum source with properties consistent with a classical nova but probably inconsistent with colliding protostars. Considering all VVV transients that could have been projected against a catalogued IRDC raises the probability of a chance association to p = 0.13-0.24. After weighing several options, it appears likely that VVV-WIT-01 was a classical nova event located behind an IRDC....
Volume
492
Issue
4
Start page
4847
Uri
Url
Issn Identifier
0035-8711
Ads BibCode
2020MNRAS.492.4847L
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

staa155.pdf

Description
Pdf editoriale
Size

2.76 MB

Format

Adobe PDF

Checksum (MD5)

f9503497988bc4c5df76d03d4ef13438