Extinction and dust/gas ratio in the H?i ridge region of the LMC based on the IRSF/SIRIUS near-infrared survey
Extinction and dust/gas ratio in the H?i ridge region of the LMC based on the IRSF/SIRIUS near-infrared survey
复制标题
基于IRSF/SIRIUS近红外调查的LMC H?i海脊区域的消光和尘/气比
DOI：
10.1093/pasj/psz078
复制
发表时间：
2019
影响因子：
2.3
通讯作者：
and Tsuge K.
中科院分区：
文献类型：
--
作者：
Furuta T.;Kaneda H.;Kokusho T.;Ishihara D.;Nakajima Y.;Fukui Y.;and Tsuge K.
We present a dust extinctionAVmap of the Large Magellanic Cloud (LMC) in the Hiridge region using the InfraRed Survey Facility (IRSF) near-infrared (IR) data, and compare theAVmap with the total hydrogen column densityN(H) maps derived from the CO and Hiobservations. In the LMC Hiridge region, the two-velocity Hicomponents (plus an intermediate velocity component) are identified, and the young massive star cluster is possibly formed by collision between them. In addition, one of the components is suggested to be an inflow gas from the Small Magellanic Cloud (SMC) which is expected to have even lower metallicity gas (Fukui et al. , PASJ, 69, L5). To evaluate dust/gas ratios in the Hiridge region in detail, we derive theAVmap from the near-IR color excess of the IRSF data updated with the latest calibration, and fit the resultantAVmap with a combination of theN(H) maps of the different velocity components to decompose it successfully into the three components. As a result, we find difference by a factor of 2 inAV/N(H) between the components. In additon, the CO-to-H2conversion factor also indicates difference between the components, implying a difference in the metallicity. Our results are likely to support the scenario that the gas in the LMC Hiridge region is contaminated with an inflow gas from the SMC with a geometry consistent with the on-going collision between the two-velocity components.
