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We study the morphological properties of mid-infrared selected galaxies at $1.0<z<1.7$ in the SMACS J0723.3-7327 cluster field, to investigate the mechanisms of galaxy mass assembly and structural formation at cosmic noon. We develop a new…

Astrophysics of Galaxies · Physics 2023-08-14 Zhaoran Liu , Takahiro Morishita , Tadayuki Kodama

Using the Planck far-infrared and Arecibo GALFA 21-cm line surveys, we identified a set of isolated interstellar clouds (approximately degree-sized on the sky and comprising 100 solar masses) and assessed the ratio of gas mass to dust mass.…

Astrophysics of Galaxies · Physics 2015-10-07 William T. Reach , Carl Heiles , Jean-Philippe Bernard

Recent submillimeter and far-infrared wavelength observations of absorption in the rotational ground-state lines of various simple molecules against distant Galactic continuum sources have opened the possibility of studying the chemistry of…

Astrophysics of Galaxies · Physics 2017-02-21 B. Winkel , H. Wiesemeyer , K. M. Menten , M. Sato , A. Brunthaler , F. Wyrowski , D. Neufeld , M. Gerin , N. Indriolo

We report the results from a new, highly sensitive ($\Delta T_{mb} \sim 3 $mK) survey for thermal OH emission at 1665 and 1667 MHz over a dense, 9 x 9-pixel grid covering a $1\deg$ x $1\deg$ patch of sky in the direction of $l = 105\deg, b…

Astrophysics of Galaxies · Physics 2019-10-09 Michael P. Busch , Ronald J. Allen , Philip D. Engelke , David E. Hogg , David A. Neufeld , Mark G. Wolfire

We present X-ray dust scattering halo results based on our 76 ks {\it Chandra} ACIS-S/HETGS observation of the LMXB dipping source 4U 1624-490. Through analysis of the halo light curves with 2-6 keV spectra over the persistent and dipping…

Astrophysics · Physics 2011-02-11 Jingen Xiang , Julia C. Lee , Michael A. Nowak

It is commonly assumed that cold and dense Infrared Dark Clouds (IRDCs) likely represent the birth sites massive stars. Therefore, this class of objects gets increasing attention. To enlarge the sample of well-characterised IRDCs in the…

Solar and Stellar Astrophysics · Physics 2015-05-13 T. Vasyunina , H. Linz , Th. Henning , B. Stecklum , S. Klose , L. -A. Nyman

We found that in regions of high mass star formation the CS emission correlates well with the dust continuum emission and is therefore a good tracer of the total mass while the N$_2$H$^+$ distribution is frequently very different. This is…

Fifty-one dense cores associated with water masers were mapped at 350 micron. These cores are very luminous, 10^3 < Lbol/Lsun < 10^6, indicative of the formation of massive stars. Dust continuum contour maps and photometry are presented for…

Astrophysics · Physics 2011-05-05 Kaisa E. Mueller , Yancy L. Shirley , Neal J. Evans , Heather R. Jacobson

Density profiles of isolated cores derived from thermal dust continuum emission rely on models of dust properties, such as mass opacity, which are poorly constrained. With complementary measures from near-infrared extinction maps, we can…

Astrophysics of Galaxies · Physics 2017-11-01 K. Webb , J. Di Francesco , S. Sadavoy , K. Thanjavur , R. Launhardt , Y. Shirley , A. Stutz , J. Abreu Vicente , J. Kainulainen

Our main purpose is to estimate the effect of assuming uniform density on the line-of-sight in PDR chemistry models, compared to a more realistic distribution for which total gas densities may well vary by several orders of magnitude. A…

Astrophysics of Galaxies · Physics 2016-11-11 François Levrier , Franck Le Petit , Patrick Hennebelle , Pierre Lesaffre , Maryvonne Gerin , Edith Falgarone

Using UV spectra obtained with FUSE, HST, and/or IUE, we determine interstellar column densities of 12CO, 13CO, and/or C_2 for ten Galactic sight lines with 0.37<E(B-V)<0.72. The N(CO)/N(H_2) ratio varies over a factor of 100 in this…

Astrophysics · Physics 2009-05-29 P. Sonnentrucker , D. E. Welty , J. A. Thorburn , D. G. York

We report a new search for 12CO(1-0) emission in high-velocity clouds (HVCs) performed with the IRAM 30 m telescope. This search was motivated by the recent detection of cold dust emission in the HVCs of Complex C. Despite a spatial…

Astrophysics · Physics 2009-11-13 M. Dessauges-Zavadsky , F. Combes , D. Pfenniger

It has often been suggested that an alternative to the standard CO/21-cm method for estimating the mass of the interstellar medium (ISM) in a galaxy might be to estimate the mass of the ISM from the continuum dust emission. In this paper,…

We have recently detected CO lines in the well-known filaments around NGC 1275, the galaxy at the centre of the Perseus cluster of galaxies. These previous observations, with the HERA multi-beam array at the IRAM 30m telescope enabled us to…

Astrophysics · Physics 2009-11-13 P. Salomé , F. Combes , Y. Revaz , A. C. Edge , N. A. Hatch , A. C. Fabian , R. M. Johnstone

Context: The study of dust emission at millimeter wavelengths is important to shed light on the dust properties and physical structure of pre-stellar cores, the initial conditions in the process of star and planet formation. Aims: Using two…

We study the correlation between far-infared/submm dust emission and atomic gas column density in order to derive the properties of the high Galactic latitude, low density, Milky Way cirrus in the foreground of the Virgo cluster of…

Characterizing prestellar cores in star-forming regions is an important step towards the validation of theoretical models of star formation. Thanks to their sub-arcsecond resolution, ALMA observations can potentially provide samples of…

Astrophysics of Galaxies · Physics 2023-05-05 Paolo Padoan , Veli-Matti Pelkonen , Mika Juvela , Troels Haugbølle , Åke Nordlund

We present fully sampled ~3' resolution images of the 12CO(J=2-1), 13CO(J=2-1), and C18O(J=2-1) emission taken with the newly developed 1.85-m mm-submm telescope toward the entire area of the Orion A and B giant molecular clouds. The data…

The connection between dense gas cores and their infant protostars is key to understanding how stars form in molecular clouds. In this paper we investigate the properties, persistence, and protostellar content of cores that would be…

We have mapped the large-scale structure of the Serpens cloud core using moderately optically thick (13CO(1--0) and CS(2--1)) and optically thin tracers (C18O(1--0), C34S(2--1), and N2H+(1--0)), using the 16-element focal plane array…

Astrophysics · Physics 2009-11-07 L. Olmi , L. Testi