The effect of diffuse background on the spatially-resolved Schmidt relation in nearby spiral galaxies
The effect of diffuse background on the spatially-resolved Schmidt relation in nearby spiral galaxies
复制标题
漫反射背景对附近螺旋星系空间分辨施密特关系的影响
DOI:
10.1051/0004-6361/201732467
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发表时间:
2020
影响因子:
6.5
通讯作者:
Kumari N
中科院分区:
文献类型:
--
作者:
Kumari N
Context.The global Schmidt law of star formation provides a power-law relation between the surface densities of star-formation rate (SFR) and gas, and successfully explains plausible scenarios of galaxy formation and evolution. However, star formation being a multi-scale process, requires spatially-resolved analysis for a better understanding of the physics of star formation.Aims.It has been shown that the removal of a diffuse background from SFR tracers, such as Hα, far-ultraviolet (FUV), infrared, leads to an increase in the slope of the sub-galactic Schmidt relation. We reinvestigate the local Schmidt relations in nine nearby spiral galaxies taking into account the effect of inclusion and removal of diffuse background in SFR tracers as well as in the atomic gas.Methods.We used multiwavelength data obtained as part of theSpitzerInfrared Nearby Galaxies Survey, Key Insights on Nearby Galaxies: a Far-Infrared Survey withHerschel, The H I Nearby Galaxy Survey, and HERA CO-Line Extragalactic Survey. Making use of a novel split of the overall light distribution as a function of spatial scale, we subtracted the diffuse background in the SFR tracers as well as the atomic gas. Using aperture photometry, we study the Schmidt relations on background subtracted and unsubtracted data at physical scales varying between 0.5–2 kpc.Results.The fraction of diffuse background varies from galaxy to galaxy and accounts to ∼34% in Hα, ∼43% in FUV, ∼37% in 24μm, and ∼75% in H I on average. We find that the inclusion of diffuse background in SFR tracers leads to a linear molecular gas Schmidt relation and a bimodal total gas Schmidt relation. However, the removal of diffuse background in SFR tracers leads to a super-linear molecular gas Schmidt relation. A further removal of the diffuse background from atomic gas results in a slope ∼1.4 ± 0.1, which agrees with dynamical models of star formation accounting for flaring effects in the outer regions of galaxies.
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影响因子:
4.8
作者:
R. Shetty;P. Clark;R. Klessen
通讯作者:
R. Klessen
DOI:
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发表时间:
2005
期刊:
Publications of the Astronomical Society of Japan Vol.57, No.5
影响因子:
--
作者:
小麦真也;小野寺幸子 et al.
通讯作者:
小野寺幸子 et al.
DOI:
10.1086/588720
发表时间:
2007-11
期刊:
The Astrophysical Journal
影响因子:
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作者:
D. Narayanan;T. J. Cox;Y. Shirley;R. Davé;L. Hernquist;C. Walker
通讯作者:
D. Narayanan;T. J. Cox;Y. Shirley;R. Davé;L. Hernquist;C. Walker
影响因子:
3.6
作者:
L. Magnani;S. Shore
通讯作者:
S. Shore
DOI:
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发表时间:
--
期刊:
影响因子:
--
作者:
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