English
Related papers

Related papers: Extragalactic H2 and its variable relation to CO

200 papers

The heating of the intergalactic medium in the early, metal-poor Universe may have been partly due to radiation from high mass X-ray binaries (HMXBs). Previous investigations on the effect of metallicity have used galaxies of different…

Astrophysics of Galaxies · Physics 2019-11-06 Sam Ponnada , Matthew Brorby , Philip Kaaret

We analyze the CO-to-H$_2$ conversion factor ($\alpha_{\rm{CO}}$) in the nearby barred spiral galaxy M83. We present new HI observations from the JVLA and single-dish GBT in the disk of the galaxy, and combine them with maps of CO(1-0)…

Astrophysics of Galaxies · Physics 2024-04-24 Amanda M Lee , Jin Koda , Akihiko Hirota , Fumi Egusa , Mark Heyer

We review here the main direct or indirect ways to detect the possible presence of large amounts of cold molecular hydrogen in the outer parts of disk galaxies, an hypothesis that we have recently developed. Direct ways range from H2…

Astrophysics · Physics 2007-05-23 F. Combes , D. Pfenniger

The most usual tracer of molecular gas is line emission from CO. However, the reliability of that tracer has long been questioned in environments different from the Milky Way. We study the relationship between H2 and CO abundances using a…

Astrophysics of Galaxies · Physics 2015-05-18 S. C. O. Glover , M. -M. Mac Low

New and archival interferometric 12CO(1->0) datasets from six nearby galaxies are combined with H_2 2.122um and H-alpha maps to explore in detail the interstellar medium in different star-forming galaxies. We investigate the relation…

The CO-to-H$_2$ conversion factor ($\alpha_\rm{CO}$) is critical to studying molecular gas and star formation in galaxies. The value of $\alpha_\rm{CO}$ has been found to vary within and between galaxies, but the specific environmental…

We measure the relationship between stellar mass and stellar metallicity, the stellar mass--metallicity relation (MZR), for 1336 star-forming galaxies at $1.6\le z\le3.0$ (<z>=2.2) using rest-frame far-ultraviolet spectra from the…

We study the dependence of the physical and observable properties of the CGM on its halo mass. We analyse 22 simulations from the Auriga suite of high resolution cosmological `zoom-in' simulations at $z=0$ with halo masses…

Astrophysics of Galaxies · Physics 2024-09-10 Andrew W. S. Cook , Freeke van de Voort , Rüdiger Pakmor , Robert J. J. Grand

Gas in galactic disks is collected by gravitational instabilities into giant atomic-molecular complexes, but only the inner, molecular parts of these structures are able to collapse to form stars. Determining what controls the ratio of…

Astrophysics · Physics 2009-11-13 Mark R. Krumholz , Christopher F. McKee , Jason Tumlinson

We study a population of significantly sub-solar enrichment galaxies at z=1.99, to investigate how molecular gas, dust and star-formation relate in low-metallicity galaxies at the peak epoch of star-formation. We target our sample with…

Astrophysics of Galaxies · Physics 2019-02-20 R. T. Coogan , M. T. Sargent , E. Daddi , F. Valentino , V. Strazzullo , M. Béthermin , R. Gobat , D. Liu , G. Magdis

Aggregates of light harvesting 2 (LH2) complexes form the major exciton-relaying domain in the photosynthetic unit of purple bacteria. Application of a generalized master equation to pairs of the B850 units of LH2 complexes, where excitons…

Chemical Physics · Physics 2026-01-08 Seogjoo J. Jang

The bulk upper critical field H_{c2}(T) of superconducting MgB_2 and its anisotropy are established by analyzing experimental data on the temperature and magnetic field dependences of the ab-plane thermal conductivity of a…

Superconductivity · Physics 2009-11-07 A. V. Sologubenko , J. Jun , S. M. Kazakov , J. Karpinski , H. R. Ott

We estimate flux ratios of the extrasolar planet XO-2b to its host star XO-2 at 3.6, 4.5, 5.8 and 8.0 micron with IRAC on the Spitzer Space Telescope to be 0.00081 +- 0.00017, 0.00098 +- 0.00020, 0.00167 +- 0.00036 and 0.00133 +- 0.00049,…

Solar and Stellar Astrophysics · Physics 2011-02-11 Pavel Machalek , Peter R. McCullough , Adam Burrows , Christopher J. Burke , Joseph L. Hora , Christopher M. Johns-Krull

We present numerical simulations of molecular clouds (MCs) with self-consistent CO gas-phase and isotope chemistry in various environments. The simulations are post-processed with a line radiative transfer code to obtain $^{12}$CO and…

Astrophysics of Galaxies · Physics 2016-04-25 László Szűcs , Simon C. O. Glover , Ralf S. Klessen

We examine colors from 3.6 micron to 24 micron as a function of metallicity (O/H) for a sample of 34 galaxies. The galaxies range over 2 orders of magnitude in metallicity. They display an abrupt shift in the 8 micron to 24 micron color…

Astrophysics · Physics 2009-11-11 C. W. Engelbracht , K. D. Gordon , G. H. Rieke , M. W. Werner , D. A. Dale , W. B. Latter

We present an analysis of the chemical abundance properties of $\approx$650 star-forming galaxies at $z \approx0.6-1.8$. Using integral-field observations from the $K$-band Multi-Object Spectrograph (KMOS), we quantify the [NII]/H$\alpha$…

We investigate the relationship between the dust-to-metals ratio (D/M) and the local interstellar medium environment at ~2 kpc resolution in five nearby galaxies: IC342, M31, M33, M101, and NGC628. A modified blackbody model with a broken…

I discuss QCD sum rules determinations of the form factors governing the decay $B \to \pi (\rho) \ell \nu$. For some of these form factors the computed dependence on the momentum transferred does not agree with the expectation from the…

High Energy Physics - Phenomenology · Physics 2010-11-11 Pietro Colangelo

The N2 index ([N II]6584/Ha) is used to determine emission line galaxy metallicities at all redshifts, including high redshift, where galaxies tend to be metal-poor. The initial aim of the work was to improve the calibrations used to infer…

Astrophysics of Galaxies · Physics 2015-06-23 A. B. Morales-Luis , E. Perez-Montero , J. Sanchez Almeida , C. Munoz Tunon

CO J = 5 - 4 and J = 2 - 1 emission lines were detected towards the extremely red galaxy (ERG) HR10 (J164502+4626.4) at z=1.44. The CO intensities imply a molecular gas mass M(H2) of 1.6 x 10^{11} h^{-2}_50 solar masses, and, combined with…

Astrophysics · Physics 2011-05-23 Paola Andreani , Andrea Cimatti , Laurent Loinard , Huub Roettgering