THE GLOBAL STAR FORMATION LAWS OF GALAXIES FROM A RADIO CONTINUUM PERSPECTIVE
文献类型：期刊论文
| 作者 | Liu, L.1,2,4 ; Gao, Y.1; Greve, T. R.3
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| 刊名 | ASTROPHYSICAL JOURNAL
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| 出版日期 | 2015-05-20 |
| 卷号 | 805期号:1页码:31 |
| 关键词 | galaxies: evolution galaxies: ISM galaxies: spiral galaxies: starburst stars: formation |
| 英文摘要 | We study the global star formation law-the relation between gas and star formation (SF) rates-in a sample of 181 local galaxies with infrared (IR) luminosities spanning almost five orders of magnitude (10(7.8) - 10(12.3) L-circle dot), which includes 115 normal spiral galaxies and 66 (ultra) luminous IR galaxies ((U) LIRGs, L-IR >= 10(11) L-circle dot). We derive their atomic, molecular gas, and dense molecular gas masses using newly available HI, CO, and HCN data from the literature, and SF rates are determined both from total IR (8-1000 mu m) and 1.4 GHz radio continuum (RC) luminosities. In order to derive the disk-averaged surface densities of gas and SF rates, we have taken a novel approach and used high-resolution RC observations to measure the radio sizes for all 181 galaxies. In our sample, we find that the surface density of dense molecular gas (as traced by HCN) has the tightest correlation with that of SF rates (Sigma(SFR)), and is linear in log-log space (power-law slope of N = 1.01 +/- 0.02) across the full galaxy sample. The correlation between surface densities of molecular gas (Sigma(H2), traced by CO) and Sigma(SFR) is sensitive to the adopted value of the CO-to-H-2 conversion factor (alpha(CO)) used to infer molecular gas masses from CO luminosities. For a fixed Galactic value of alpha(CO), a power law index of 1.14 +/- 0.02 is found. If instead we adopt values for alpha(CO) of 4.6 and 0.8 for disk galaxies and (U) LIRGs, respectively, we find the two galaxy populations separate into two distinct Sigma(SFR) versus Sigma(H2) relations. Finally, applying a continuously varying alpha(CO) to our sample, we recover a single Sigma(SFR)-Sigma(H2) relation with slope of 1.60 +/- 0.03. The Sigma(SFR) is a steeper function of total gas Sigma(gas) (molecular gas with atomic gas) than that of molecular gas Sigma(H2), and are tighter among low-luminosity galaxies. We find no correlation between global surface densities of SFRs and atomic gas (H I). |
| 学科主题 | 天文和天体物理 |
| WOS标题词 | Science & Technology ; Physical Sciences |
| 类目[WOS] | Astronomy & Astrophysics |
| 研究领域[WOS] | Astronomy & Astrophysics |
| 关键词[WOS] | LUMINOUS INFRARED GALAXIES ; DENSE MOLECULAR GAS ; WESTERBORK HI SURVEY ; CO-TO-H-2 CONVERSION FACTOR ; HIGH-RESOLUTION CO ; MILLIMETER INTERFEROMETRIC HCN(1-0) ; NEUTRAL HYDROGEN DISTRIBUTION ; NEARBY SPIRAL GALAXIES ; ACTIVE GALACTIC NUCLEI ; 1.49 GHZ ATLAS |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000354991300031 |
| 源URL | [http://libir.pmo.ac.cn/handle/332002/14849]  |
| 专题 | 紫金山天文台_星系中的恒星形成研究团组 |
| 作者单位 | 1.Purple Mt Observ, Key Lab Radio Astron, Nanjing 210008, Jiangsu, Peoples R China 2.Max Planck Inst Radioastron, D-53121 Bonn, Germany 3.UCL, Dept Phys & Astron, London WC1E 6BT, England 4.Univ Chinese Acad Sci, Beijing 100039, Peoples R China |
| 推荐引用方式 GB/T 7714 | Liu, L.,Gao, Y.,Greve, T. R.. THE GLOBAL STAR FORMATION LAWS OF GALAXIES FROM A RADIO CONTINUUM PERSPECTIVE[J]. ASTROPHYSICAL JOURNAL,2015,805(1):31. |
| APA | Liu, L.,Gao, Y.,&Greve, T. R..(2015).THE GLOBAL STAR FORMATION LAWS OF GALAXIES FROM A RADIO CONTINUUM PERSPECTIVE.ASTROPHYSICAL JOURNAL,805(1),31. |
| MLA | Liu, L.,et al."THE GLOBAL STAR FORMATION LAWS OF GALAXIES FROM A RADIO CONTINUUM PERSPECTIVE".ASTROPHYSICAL JOURNAL 805.1(2015):31. |
入库方式： OAI收割
来源：紫金山天文台
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