Far-infrared dust properties in the Galaxy and the Magellanic Clouds

Simple item page
dc.creatorHirashita, Hiroyuki
dc.creatorHibi, Yasunori
dc.creatorShibai, Hiroshi
dc.date2007-03-20
dc.date.accessioned2026-07-07T11:01:08Z
dc.date.available2026-07-07T11:01:08Z
dc.descriptionA recent data analysis of the far-infrared (FIR) map of the Galaxy and the Magellanic Clouds has shown that there is a tight correlation between two FIR colours: the 60 um-100 um and 100 um-140 um colours. This FIR colour relation called ``main correlation'' can be interpreted as indicative of a sequence of various interstellar radiation fields with a common FIR optical property of grains. In this paper, we constrain the FIR optical properties of grains by comparing the calculated FIR colours with the observational main correlation. We show that neither of the ``standard'' grain species (i.e. astronomical silicate and graphite grains) reproduces the main correlation. However, if the emissivity index at ~ 100--200 um is changed to ~ 1--1.5 (not ~ 2 as the above two species), the main correlation can be successfully explained. Thus, we propose that the FIR emissivity index is ~ 1--1.5 for the dust in the Galaxy and the Magellanic Clouds at ~ 100--200 um. We also consider the origin of the minor correlation called ``sub-correlation'', which can be used to estimate the Galactic star formation rate.
dc.description12 pages, 8 figures, accepted for publication in MNRAS
dc.identifierhttps://arxiv.org/abs/astro-ph/0703517
dc.identifierhttp://arxiv.org/abs/astro-ph/0703517
dc.identifierMon.Not.Roy.Astron.Soc.379:974-984,2007
dc.identifierdoi:10.1111/j.1365-2966.2007.11745.x
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/187870
dc.subjectAstrophysics
dc.titleFar-infrared dust properties in the Galaxy and the Magellanic Clouds
dc.typetext

Files

Collections

arXiv