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相关论文: Extremely weak CO emission in IZw 18

200 篇论文

We present new results on CO depletion in a sample of nearby pre-stellar cores, based on observations of the millimeter C17O and C18O lines and the 1.3 mm dust emission with the IRAM 30m telescope. In most cases, the distribution of CO is…

Of the almost 40 star forming galaxies at z>~5 (not counting QSOs) observed in [CII] to date, nearly half are either very faint in [CII], or not detected at all, and fall well below expectations based on locally derived relations between…

星系天体物理 · 物理学 2017-09-13 K. P. Olsen , T. R. Greve , D. Narayanan , R. Thompson , R. Davé , L. N. Rios , S. Stawinski

This paper reports the latest results from a millimeter-wave (CO) spectroscopic survey of IRAS-detected radio galaxies with L_1.4GHz ~ 10^23-28 W/Hz in the redshift range z ~ 0.02-0.15. The IRAS flux-limited sample contains 33 radio…

天体物理学 · 物理学 2009-11-11 A. S. Evans , J. M. Mazzarella , J. A. Surace , D. T. Frayer , K. Iwasawa , D. B. Sanders

We present detections of the CO(4-3) and [C I] 609 $\mu$m spectral lines, as well as the dust continuum at 480.5 GHz (rest-frame), in 3C 368, a Fanaroff-Riley class II (FR-II) galaxy at redshift (z) 1.131. 3C 368 has a large stellar mass, ~…

星系天体物理 · 物理学 2019-09-04 C. Lamarche , G. J. Stacey , A. Vishwas , D. Brisbin , C. Ferkinhoff , T. Nikola , S. J. U. Higdon , J. Higdon

We present IRAM Plateau de Bure interferometric detections of CO(1-0) emission from a 24um-selected sample of star-forming galaxies at z=0.4. The galaxies have PAH 7.7um-derived star formation rates of SFR~30-60 M_Sun/yr and stellar masses…

宇宙学与河外天体物理 · 物理学 2015-05-27 James E. Geach , Ian Smail , Sean M. Moran , Lauren A. MacArthur , Claudia del P. Lagos , Alastair C. Edge

Wolf-Rayet stars (WR) have been detected in the NW region of the metal-poor starburst galaxy IZw 18. The integrated luminosity and FWHM of the bumps at 4650 A and 5808 A are consistent with the presence of a few individual stars of WC4 or…

天体物理学 · 物理学 2007-05-23 F. Legrand , D. Kunth , J. -R. Roy , J. M. Mas-Hesse , J. R. Walsh

With the installation of the Cosmic Origins Spectrograph on the Hubble Space Telescope, measurements of the metal content of the low redshift intergalactic medium (IGM) are now available. Using a new grid-based model for diffuse gas coupled…

宇宙学与河外天体物理 · 物理学 2015-05-20 Genevieve M. Shattow , Darren J. Croton , Antonio Bibiano

The circumgalactic medium (CGM) remains one of the least constrained components of galaxies and as such has significant potential for advancing galaxy formation theories. In this work, we vary the extragalactic ultraviolet background for a…

星系天体物理 · 物理学 2016-08-31 Lauren Corlies , David Schiminovich

We test the ability of equilibrium galactic disk and one-zone interstellar medium models to describe the physical and emission properties of quasar hosts, submillimeter galaxies, and Lyman-alpha emitters at z>~6. The size, line widths, star…

宇宙学与河外天体物理 · 物理学 2017-03-08 Joseph A. Muñoz , Steven R. Furlanetto

As the primary fuel for star formation, molecular gas plays a key role in galaxy evolution. A number of techniques have been used for deriving the mass of molecular reservoirs in the early Universe (e.g., [CII]158$\mu$m, [CI], dust…

星系天体物理 · 物理学 2023-12-11 G. C. Jones , J. Witstok , A. Concas , N. Laporte

We report CO detections in 17 out of 19 infrared ultraluminous QSO (IR QSO) hosts observed with the IRAM 30m telescope. The cold molecular gas reservoir in these objects is in a range of 0.2--2.1$\times 10^{10}M_\odot$ (adopting a…

宇宙学与河外天体物理 · 物理学 2015-06-04 X. Y. Xia , Y. Gao , C. -N. Hao , Q. H. Tan , S. Mao , A. Omont , B. O. Flaquer , S. Leon , P. Cox

We present {\it JWST} observations of a gravitationally-lensed, extremely metal-poor galaxy at redshift $z=8.203\pm 0.001$ from the CANUCS survey. Based on the low oxygen to Balmer line ratios we infer a gas-phase metallicity of $12+{\rm…

Carbon monoxide (CO) provides crucial information about the molecular gas properties of galaxies. While $^{12}$CO has been targeted extensively, isotopologues such as $^{13}$CO have the advantage of being less optically thick and…

The specific star-formation rate of star-forming `main sequence' galaxies significantly decreased since z~1.5, due to the decreasing molecular gas fraction and star formation efficiency. However, the radio-infrared (IR) correlation has not…

星系天体物理 · 物理学 2025-01-29 B. Vollmer , J. Freundlich , P. Gratier , Th. Lizee , M. Lendrin , J. Braine , M. Soida

Nearby dwarf irregular galaxies are ideal laboratories for studying the interstellar medium (ISM) at low metallicity, which is expected to be common for galaxies at very high redshift being observed by the James Webb Space Telescope. We…

星系天体物理 · 物理学 2023-08-02 Chia-Yu Hu , Amiel Sternberg , Ewine F. van Dishoeck

The central star-forming regions in three blue compact dwarf galaxies (He 2-10, NGC 5253, and II Zw 40) were observed in the 340 GHz (880 micron) band at 5 arcsec resolution with the Submillimetre Array (SMA). Continuum emission associated…

宇宙学与河外天体物理 · 物理学 2015-06-12 Hiroyuki Hirashita

Stars form out of the densest parts of molecular clouds. Far-IR emission can be used to estimate the Star Formation Rate (SFR) and high dipole moment molecules, typically HCN, trace the dense gas. A strong correlation exists between HCN and…

星系天体物理 · 物理学 2016-12-28 J. Braine , Y. Shimajiri , P. André , S. Bontemps , Yu Gao , Hao Chen , C. Kramer

We investigate the CO excitation and interstellar medium (ISM) conditions in a cold gas mass-selected sample of 22 star-forming galaxies at $z=0.46-3.60$, observed as part of the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field…

We present new measurements of the ground state fine-structure line of atomic carbon at 492 GHz in a variety of nearby external galaxies, ranging from spiral to irregular, interacting and merging types. In comparison with CO(1-0), the…

天体物理学 · 物理学 2009-10-31 Maryvonne Gerin , Thomas G. Phillips

Unobscured quasars (QSOs) are predicted to be the final stage in the evolutionary sequence from gas-rich mergers to gas-depleted, quenched galaxies. Studies of this population, however, find a high incidence of far-infrared-luminous sources…