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Related papers: Molecular gas and star formation in M81

200 papers

We present images from the Solar Blind Channel on HST that resolve hundreds of far ultraviolet (FUV) emitting stars in two ~1 kpc$^2$ interarm regions of the grand-design spiral M101. The luminosity functions of these stars are compared…

We compare the detailed distributions of HI, H alpha, and 150 nm far-UV continuum emission in the spiral arms of M81 at a resolution of 9" (linear resolution 150 pc at 3.7 Mpc distance). The bright H alpha emission peaks are always…

Astrophysics · Physics 2009-10-30 R. J. Allen , J. H. Knapen , R. Bohlin , T. Stecher

We investigate the sub-kiloparsec (sub-kpc) molecular ISM structure and its relation to the galactic environment and star formation in the barred spiral galaxy M83 (NGC 5236). We employ the gas density histogram (GDH), which quantifies…

In this review, I discuss recent detailed studies of individual molecular clouds in M33 in higher rotational transitions of CO, 13CO, and the fine structure line of atomic carbon. These data reveal that the temperature and density of the…

Astrophysics · Physics 2007-05-23 C. D. Wilson

We report observations made with the IRAM 30m radiotelescope in the HCN(1-0) and HCO+(1-0) lines towards a sample of molecular complexes (GMCs) in the disk of the Andromeda galaxy (M31). The targets were identified bright CO GMCs selected…

We present ALMA 2-mm continuum and CO (2-1) spectral line imaging of the gravitationally lensed z=0.654 star-forming/quasar composite RX J1131-1231 at 240-400 mas angular resolution. The continuum emission is found to be compact and…

The outskirts of galaxies offer extreme environments where we can test our understanding of the formation, evolution, and destruction of molecules and their relationship with star formation and galaxy evolution. We review the basic…

Astrophysics of Galaxies · Physics 2016-12-19 Linda C. Watson , Jin Koda

There is a linear relation between the mass of dense gas, traced by the HCN(1-0) luminosity, and the star formation rate (SFR), traced by the far-infrared luminosity. Recent observations of galactic disks have shown some systematic…

Astrophysics of Galaxies · Physics 2017-02-22 Hao Chen , Jonathan Braine , Yu Gao , Jin Koda , Qiusheng Gu

The nearby S0 galaxy IC 5181 is studied to address the origin of the ionized gas component that orbits the galaxy on polar orbit. We perform detailed photometric and spectroscopic observations measuring the surface brightness distribution…

Astrophysics of Galaxies · Physics 2014-04-04 Alessandro Pizzella , Lorenzo Morelli , Enrico Maria Corsini , Elena Dalla Bonta` , Mary Cesetti

It remains unclear what sets the efficiency with which molecular gas transforms into stars. Here we present a new VLA map of the spiral galaxy M51 in 33GHz radio continuum, an extinction-free tracer of star formation, at 3" scales (~100pc).…

We present spatial variations of the CO J=2-1/1-0 line ratio in M83 using Total Power array data from ALMA. While the intensities of these two lines correlate tightly, the ratio varies over the disk, with a disk average ratio of 0.69, and…

The Andromeda galaxy (M31) is the most nearby giant spiral galaxy, an opportunity to study with high resolution dynamical phenomena occurring in nuclear disks and bulges, able to explain star formation quenching, and galaxy evolution…

Astrophysics of Galaxies · Physics 2025-05-29 Lucie Cros , Françoise Combes , Anne-Laure Melchior , Thomas Martin

We report on observations of CO(1-0) emission from the chemically young starburst galaxy Mrk 109. These observations were part of a study to constrain the O2/CO ratio in metal-deficient galaxies, which were motivated by theoretical work…

Astrophysics · Physics 2016-08-30 D. T. Frayer , E. R. Seaquist , T. X. Thuan , A. Sievers

High-density molecular gas plays a vital role in supporting star formation within galaxies. However, traditional tracers of dense gas, such as the low-$J$ transitions of HCN and HCO$^+$, are predominantly optically thick. This…

Astrophysics of Galaxies · Physics 2025-09-16 Fei Li , Zhi-Yu Zhang , Junzhi Wang , Gan Luo

Using the IRAM 30m telescope, we have detected the CO J=2-1, 4-3, 5-4, and 6-5 emission lines in the millimeter-bright, blank-field selected AGN COSMOS J100038+020822 at redshift z=1.8275. The sub-local thermodynamic equilibrium (LTE)…

High angular resolution optical and near-infrared images are used to investigate the central regions of the nearby Sb galaxy M81 (NGC3031). The spectral-energy distribution of the circumnuclear region, which extends out to 1.5 arcsec (~ 24…

Astrophysics · Physics 2009-10-31 T. J. Davidge , S. Courteau

We have mapped the inner 360'' regions of M51 in the 158micron [CII] line at 55'' spatial resolution using the Far-infrared Imaging Fabry-Perot Interferometer (FIFI) on the Kuiper Airborne Observatory (KAO). The emission is peaked at the…

Astrophysics · Physics 2009-11-06 T. Nikola , N. Geis , F. Herrmann , S. C. Madden , A. Poglitsch , G. J. Stacey , C. H. Townes

Aside from the grand-design stellar spirals appearing in the disk of M81, a pair of stellar spiral arms situated well inside the bright bulge of M81 has been recently discovered by Kendall et al. (2008). The seemingly unrelated pairs of…

Astrophysics of Galaxies · Physics 2015-06-18 Chien-Chang Feng , Lien-Hsuan Lin , Hsiang-Hsu Wang , Ronald E. Taam

Carbon monoxide (CO) emission is the most widely used tracer of the bulk molecular gas in the interstellar medium (ISM) in extragalactic studies. The CO-to-H$_2$ conversion factor, $\alpha_{\rm CO}$, links the observed CO emission to the…

The outer Galaxy presents an optimal setting for investigating molecular clouds and star formation in environments with low metallicity. A total of 72 Galactic edge clouds were surveyed using the CO\,(2--1) line with the IRAM\,30\,m…