X-shooter search for outgassing from Main Belt Comet P/2012 T1 (Pan-STARRS)

Abstract

Main Belt Comets are a recently identified population of minor bodies with stable asteroid-like orbits but cometary appearances. Sublimation of water ice is the most likely mechanism for their recurrent activity (i.e. dust tails and dust comae), although there has been no direct detection of gas. These peculiar objects could hold the key to the origin of water on Earth. In this paper we present a search for the gas responsible for lifting dust from P/2012 T1 (Pan-STARRS), and review previous attempts at such measurements. To date such searches have mainly been indirect, looking for the common cometary gas CN rather than gasses related to water itself. We use the VLT and X-shooter to search for emission from OH in the UV, a direct dissociation product of water. We do not detect any emission lines, and place an upper limit on water production rate from P/2012 T1 of $8-9\times 10^{25}$ molecules s${}^{-1}$. This is similar to limits derived from observations using the Herschel space telescope. We conclude that the best current facilities are incapable of detecting water emission at the exceptionally low levels required to produce the observed activity in Main Belt Comets.

6 pages, accepted for publication in A&A

References in corpus (6)

• A collision in 2009 as the origin of the debris trail of asteroid P/2010 A2
• Main-Belt Comet P/2008 R1 (Garradd)
• Disintegrating Asteroid P/2013 R3
• An upper limit for the water outgassing rate of the main-belt comet 176P/LINEAR observed with Herschel/HIFI
• New Active Asteroid 313P/Gibbs
• Search for the Return of Activity in Active Asteroid 176P/LINEAR

Cited by in corpus (6)

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• Comet 66P/du Toit: not a near Earth main belt comet
• Cometary science with CUBES
• The CUBES Science Case