PMO OpenIR  > 星系中的恒星形成研究团组
OUTSIDE-IN SHRINKING OF THE STAR-FORMING DISK OF DWARF IRREGULAR GALAXIES
Zhang, Hong-Xin1,2,3,4; Hunter, Deidre A.1; Elmegreen, Bruce G.5; Gao, Yu2,3; Schruba, Andreas6
2012-02-01
Source PublicationASTRONOMICAL JOURNAL
ISSN0004-6256
Volume143Issue:2Pages:47(27pp)
AbstractWe have studied multi-band surface brightness profiles of a representative sample of 34 nearby dwarf irregular galaxies. Our data include Galaxy Evolution Explorer (GALEX) FUV/NUV, UBV, and Ha and Spitzer 3.6 mu m images. These galaxies constitute the majority of the LITTLE THINGS survey (Local Irregulars That Trace Luminosity Extremes The H I Nearby Galaxy Survey). By modeling the azimuthal averages of the spectral energy distributions with a complete library of star formation histories, we derived the stellar mass surface density distributions and the star formation rate averaged over three different timescales: the recent 0.1 Gyr, 1 Gyr, and a Hubble time. We find that, for similar to 80% (27 galaxies) of our sample galaxies, radial profiles (at least in the outer part) at shorter wavelengths, corresponding to younger stellar populations, have shorter disk scale lengths than those at longer wavelengths, corresponding to older stellar populations. This indicates that the star-forming disk has been shrinking. In addition, the radial distributions of the stellar mass surface density are well described as piece-wise exponential profiles, and similar to 80% of the galaxies have steeper mass profiles in the outer disk than in the inner region. The steep radial decline of the star formation rate in the outer parts compared to that in the inner disks gives a natural explanation for the down-bending stellar mass surface density profiles. Within the inner disks, our sample galaxies on average have constant ratios of recent star formation rate to stellar mass with radius. Nevertheless, similar to 35% (12 galaxies, among which 7 have baryonic mass less than or similar to 10(8) M-circle dot) of the sample exhibit negative slopes across the observed disk, which is in contrast with the so-called inside out disk growth scenario suggested for luminous spiral galaxies. The tendency of star formation to become concentrated toward the inner disks in low-mass dwarf irregular galaxies is interpreted as a result of their susceptibility to environmental effects and regulation through stellar feedback.
KeywordGalaxies: Dwarf Galaxies: Evolution Galaxies: Irregular Galaxies: Stellar Content
Subject AreaAstronomy & Astrophysics
WOS HeadingsScience & Technology ; Physical Sciences
DOI10.1088/0004-6256/143/2/47
WOS KeywordHUBBLE-SPACE-TELESCOPE ; INFRARED SURFACE PHOTOMETRY ; STELLAR POPULATION-MODELS ; COLOR-MAGNITUDE DIAGRAM ; INSIDE-OUT FORMATION ; FORMATION HISTORIES ; SPIRAL GALAXIES ; LOCAL VOLUME ; GALACTIC DISKS ; ELLIPTIC GALAXIES
Indexed BySCI
Language英语
WOS Research AreaAstronomy & Astrophysics
WOS SubjectAstronomy & Astrophysics
WOS IDWOS:000299803600022
Citation statistics
Cited Times:67[WOS]   [WOS Record]     [Related Records in WOS]
Document Type期刊论文
Identifierhttp://libir.pmo.ac.cn/handle/332002/8073
Collection星系中的恒星形成研究团组
Affiliation1.Lowell Observ, Flagstaff, AZ 86001 USA
2.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Jiangsu, Peoples R China
3.Chinese Acad Sci, Key Lab Radio Astron, Nanjing 210008, Jiangsu, Peoples R China
4.Chinese Acad Sci, Grad Sch, Beijing 100080, Peoples R China
5.IBM TJ Watson Res Ctr, Yorktown Hts, NY 10598 USA
6.Max Planck Inst Astron, D-69117 Heidelberg, Germany
Recommended Citation
GB/T 7714
Zhang, Hong-Xin,Hunter, Deidre A.,Elmegreen, Bruce G.,et al. OUTSIDE-IN SHRINKING OF THE STAR-FORMING DISK OF DWARF IRREGULAR GALAXIES[J]. ASTRONOMICAL JOURNAL,2012,143(2):47(27pp).
APA Zhang, Hong-Xin,Hunter, Deidre A.,Elmegreen, Bruce G.,Gao, Yu,&Schruba, Andreas.(2012).OUTSIDE-IN SHRINKING OF THE STAR-FORMING DISK OF DWARF IRREGULAR GALAXIES.ASTRONOMICAL JOURNAL,143(2),47(27pp).
MLA Zhang, Hong-Xin,et al."OUTSIDE-IN SHRINKING OF THE STAR-FORMING DISK OF DWARF IRREGULAR GALAXIES".ASTRONOMICAL JOURNAL 143.2(2012):47(27pp).
Files in This Item:
File Name/Size DocType Version Access License
2012086OUTSIDE-IN SH(7948KB) 开放获取LicenseView Application Full Text
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Zhang, Hong-Xin]'s Articles
[Hunter, Deidre A.]'s Articles
[Elmegreen, Bruce G.]'s Articles
Baidu academic
Similar articles in Baidu academic
[Zhang, Hong-Xin]'s Articles
[Hunter, Deidre A.]'s Articles
[Elmegreen, Bruce G.]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Zhang, Hong-Xin]'s Articles
[Hunter, Deidre A.]'s Articles
[Elmegreen, Bruce G.]'s Articles
Terms of Use
No data!
Social Bookmark/Share
File name: 2012086OUTSIDE-IN SHRINKING OF THE STAR-FORMING DISK OF DWARF IRREGULAR GALAXIES.pdf
Format: Adobe PDF
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.