학술논문
HERschelInventory of The Agents of Galaxy Evolution (HERITAGE): The Large Magellanic Cloud dust*
Document Type
Article
Author
Meixner, M.; Galliano, F.; Hony, S.; Roman-Duval, J.; Robitaille, T.; Panuzzo, P.; Sauvage, M.; Gordon, K.; Engelbracht, C.; Misselt, K.; Okumura, K.; Beck, T.; Bernard, J.-P.; Bolatto, A.; Bot, C.; Boyer, M.; Bracker, S.; Carlson, L. R.; Clayton, G. C.; R. Chen, C.-H.; Churchwell, E.; Fukui, Y.; Galametz, M.; Hora, J. L.; Hughes, A.; Indebetouw, R.; Israel, F. P.; Kawamura, A.; Kemper, F.; Kim, S.; Kwon, E.; Lawton, B.; Li, A.; Long, K. S.; Marengo, M.; Madden, S. C.; Matsuura, M.; Oliveira, J. M.; Onishi, T.; Otsuka, M.; Paradis, D.; Poglitsch, A.; Riebel, D.; Reach, W. T.; Rubio, M.; Sargent, B.; Sewiło, M.; Simon, J. D.; Skibba, R.; Smith, L. J.; Srinivasan, S.; Tielens, A. G. G. M.; van Loon, J. Th.; Whitney, B.; Woods, P. M.
Source
Astronomy and Astrophysics; July 2010, Vol. 518 Issue: 10
Subject
Language
ISSN
00046361; 14320746
Abstract
The HERschelInventory 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 HerschelSpace 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 Herschelmission. We present the data in all 5 Herschelbands: 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 HI21 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+15making 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+25that is more consistent with a GDR inferred from extinction.