HERschel Inventory of The Agents of Galaxy Evolution (HERITAGE): The Large Magellanic Cloud dust

Type Journal Article
Names M. Meixner, F. Galliano, S. Hony, J. Roman-Duval, T. Robitaille, P. Panuzzo, M. Sauvage, K. Gordon, C. Engelbracht, K. Misselt, K. Okumura, T. Beck, J.-P. Bernard, A. Bolatto, C. Bot, M. Boyer, S. Bracker, L. R. Carlson, G. C. Clayton, C.-H. R. Chen,
Publication Astronomy and Astrophysics Letters
Volume 518
Pages L71
Date July 1, 2010
Short Title HERschel Inventory of The Agents of Galaxy Evolution (HERITAGE)
URL http://adsabs.harvard.edu/abs/2010A%26A...518L..71M
Library Catalog NASA ADS
Abstract The HERschel Inventory of The Agents of Galaxy Evolution (HERITAGE) of the Magellanic Clouds will use dust emission to investigate the life cycle of matter in both the Large and Small Magellanic Clouds (LMC and SMC). Using the Herschel Space Observatory's PACS and SPIRE photometry cameras, we imaged a 2° × 8° strip through the LMC, at a position angle of ~22.5° as part of the science demonstration phase of the Herschel mission. We present the data in all 5 Herschel bands: PACS 100 and 160 μm and SPIRE 250, 350 and 500 μm. We present two dust models that both adequately fit the spectral energy distribution for the entire strip and both reveal that the SPIRE 500 μm emission is in excess of the models by ~6 to 17%. The SPIRE emission follows the distribution of the dust mass, which is derived from the model. The PAH-to-dust mass (fPAH) image of the strip reveals a possible enhancement in the LMC bar in agreement with previous work. We compare the gas mass distribution derived from the HI 21 cm and CO J = 1-0 line emission maps to the dust mass map from the models and derive gas-to-dust mass ratios (GDRs). The dust model, which uses the standard graphite and silicate optical properties for Galactic dust, has a very low GDR = 65-18+15 making it an unrealistic dust model for the LMC. Our second dust model, which uses amorphous carbon instead of graphite, has a flatter emissivity index in the submillimeter and results in a GDR = 287-42+25 that is more consistent with a GDR inferred from extinction. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.
Tags DUST, MAGELLANIC CLOUDS, extinction, submillimeter: ISM, submillimeter: galaxies
UW-Madison Astronomy Home