中文
相关论文

相关论文: Observations of cold gas and star formation in dwa…

200 篇论文

We describe the infrared properties of a large sample of early type galaxies, comparing data from the Spitzer archive with Ks-band emission from 2MASS. While most representations of this data result in correlations with large scatter, we…

宇宙学与河外天体物理 · 物理学 2014-11-20 Pasquale Temi , Fabrizio Brighenti , William G. Mathews

We present the H-alpha flux measurements for 44 nearby dwarf galaxies, derived from the observations at the 6-m BTA telescope. H-alpha fluxes were used to determine the rate of integral star formation of galaxies, SFR. For the observed…

宇宙学与河外天体物理 · 物理学 2015-06-17 S. S. Kaisin , I. D Karachentsev

We investigate the manner in which lenticular galaxies are formed by studying their stellar kinematics: an S0 formed from a fading spiral galaxy should display similar cold outer disc kinematics to its progenitor, while an S0 formed in a…

Star formation (SF) laws are fundamental relations between the gas content of a galaxy and its star formation rate (SFR) and play key roles in galaxy evolution models. In this paper, we present new empirical SF laws of disc galaxies based…

星系天体物理 · 物理学 2019-03-08 Cecilia Bacchini , Filippo Fraternali , Giuliano Iorio , Gabriele Pezzulli

We combine a semi-analytic model of galaxy formation, tracking atomic and molecular phases of cold gas, with a three-dimensional radiative-transfer and line tracing code to study the sub-mm emission from atomic and molecular species (CO,…

宇宙学与河外天体物理 · 物理学 2015-06-17 G. Popping , J. P. Pérez-Beaupuits , M. Spaans , S. C. Trager , R. S. Somerville

The conversion factor from carbon monoxide (CO) intensity to molecular gas mass is a source of large uncertainty in understanding gas and its relation to star formation in galaxies. In particular, the conversion factor in low metallicity…

星系天体物理 · 物理学 2023-11-21 Shinya Komugi , Miku Inaba , Tetsuo Shindou

Dense, cold gas is the key ingredient for star formation. Over the last two decades, HCN(1-0) emission has been utilised as the most accessible dense gas tracer to study external galaxies. We present new measurements tracing the…

The Kennicutt-Schmidt (KS) relationship between the surface density of the star formation rate (SFR) and the gas surface density has three distinct power laws that may result from one model in which gas collapses at a fixed fraction of the…

星系天体物理 · 物理学 2018-02-21 Bruce G. Elmegreen

We present ALMA observations of the [C II] 158 micron fine structure line and dust continuum emission from the host galaxies of five redshift 6 quasars. We also report complementary observations of 250 GHz dust continuum and CO (6-5) line…

Observations of low order CO transitions represent the most direct way to study galaxies' cold molecular gas, the fuel of star formation. Here we present the first detection of CO(2-1) in a galaxy lying on the main-sequence of star-forming…

We present results from the KMOS lensing survey-KLENS which is exploiting gravitational lensing to study the kinematics of 24 star forming galaxies at $1.4<z<3.5$ with a median mass of $\rm log(M_\star/M_\odot)=9.6$ and median star…

Optically thin cooling gas at most temperatures above 30K will make condensations by pressure pushing material into cool dense regions. This works without gravity. Cooling condensations will flatten and become planar/similarity solutions.…

天体物理学 · 物理学 2009-11-06 D. Lynden-Bell , C. A. Tout

We utilize detailed time-varying models of the coupled evolution of stars and the HI, H_2, and CO-bright H_2 gas phases in galaxy-sized numerical simulations to explore the evolution of gas-rich and/or metal-poor systems, expected to be…

宇宙学与河外天体物理 · 物理学 2015-05-19 Padelis P. Papadopoulos , Federico I. Pelupessy

Evidence is summarized that suggests that when a protogalaxy collapses, a fraction $f$ of its gas fails to heat to the virial temperature, where $f$ is large for haloes less massive than the value $M^*$ associated with $L^*$ galaxies. Stars…

天体物理学 · 物理学 2008-11-26 James Binney

The GMRT observations of the HI 21~cm-line emission from 13~nearby dwarf star-forming galaxies are presented. The ranges of star formation rates and stellar masses of the sample galaxies are 0.03 -- 1.7~$M_\odot~{\rm yr}^{-1}$ and 0.04 --…

星系天体物理 · 物理学 2020-09-09 Sumit Jaiswal , Amitesh Omar

We select 947 star-forming galaxies from SDSS-DR7 with [O~{\sc iii}]$\lambda$4363 emission lines detected at a signal-to-noise {ratio }larger than 5$\sigma$. Their electron temperatures and direct oxygen abundances are {then }determined.…

星系天体物理 · 物理学 2015-06-19 WeiBin Shi , YanChun Liang , Xu Shao , XiaoWei Liu , Gang Zhao , Francois Hammer , Yong Zhang , Hector Flores , GuiPing Ruan , Li Zhou

Low-metallicity dwarf galaxies often show no or little CO emission, despite the intense star formation observed in local samples. Both simulations and resolved observations indicate that molecular gas in low-metallicity galaxies may reside…

We propose a simple model for the formation of dwarf spheroidal galaxies, in which stars are assumed to have formed from isothermal gas in hydrostatic equilibrium inside extended dark matter halos. After expelling the leftover gas, the…

天体物理学 · 物理学 2009-11-10 Sergey Mashchenko , H. M. P. Couchman , Alison Sills

In order to constrain parameters in galaxy formation theories, especially those for a star formation process, we investigate cold gas in elliptical galaxies. We calculate the detection rate of cold gas in them using a semi-analytic model of…

天体物理学 · 物理学 2015-06-24 Yutaka Fujita , Masahiro Nagashima , Naoteru Gouda

We present Halpha narrow-band imaging of 17 dwarf irregular galaxies (dIs) in the nearby Centaurus A Group. Although all large galaxies of the group have a current or recent enhanced star formation episode, the dIs have normal star…

星系天体物理 · 物理学 2010-11-02 Stephanie Cote , Adam Draginda , Evan D. Skillman , Bryan W. Miller