Adding HOPS to the Hunter's Brew: Insights from Herschel on Star Formation in Orion
Tom Megeath, Babar Ali, Nuria Calvet, Mayra Osorio, Charles Poteet, Manoj Puravankara, Amy Stutz, John Tobin, Roland Vavrek, and Dan Watson
To understand how core mass functions evolve into initial mass functions, we require a detailed understanding of protostellar evolution. The Herschel Orion Protostar Survey (HOPS) is furthering this goal by performing a study of 286 protostellar candidates in the Orion molecular clouds. By combining Herschel 70 and 160 μm photometry with 3.6 to 40 μm Spitzer photometry and spectroscopy and 1.6 μm HST imaging, HOPS aims to trace protostellar evolution in Orion from class 0 through class I. We present here a study of the 75% of HOPS targets observed so far that uses a novel method of grid-based spectral energy distribution fitting to improve estimates of the bolometric luminosity and temperature. These values are compared to models of protostellar evolution to search for both long-term variations in infall and accretion as well as episodic accretion. We compare the results across a variety of environments, from clusters to groups to isolation, to understand the impact of environment on protostellar evolution.