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Related papers: Star formation in IRDC G31.97+0.07

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High-resolution ($<$0.1pc) ALMA observations of the 30Dor-10 molecular cloud 15pc north of R136 are presented. The $^{12}$CO 2-1 emission morphology contains clumps near the locations of known mid-infrared massive protostars, as well as a…

To shed light on the time evolution of local star formation episodes in M33, we study the association between 566 Giant Molecular Clouds (GMCs), identified through the CO (J=2-1) IRAM-all-disk survey, and 630 Young Stellar Cluster…

An estimate of the degree of CO-depletion ($f_D$) provides information on the physical conditions occurring in the innermost and densest regions of molecular clouds. A key parameter in these studies is the size of the depletion radius, i.e.…

Astrophysics of Galaxies · Physics 2021-06-02 G. Sabatini , A. Giannetti , S. Bovino , J. Brand , S. Leurini , E. Schisano , T. Pillai , K. M. Menten

We present high-resolution, multiwavelength continuum and molecular-line images of the massive star forming region IRAS 18317-0757. The IR through mm spectral energy distribution can be approximated by a two-temperature model (25 and 63 K)…

Astrophysics · Physics 2009-11-16 T. R. Hunter , Q. Zhang , T. K. Sridharan

Whether ionization feedback triggers the formation of massive stars is highly debated. Using ALMA 3 mm observations with a spatial resolution of $\sim 0.05$ pc and a mass sensitivity of 1.1 $\rm M_\odot$ beam$^{-1}$ at 20 K, we investigate…

In order to study the initial conditions of massive star formation, we have previously built a sample of 463 high-mass starless clumps (HMSCs) across the inner Galactic plane covered by multiple continuum surveys. Here, we use $^{13}$…

Astrophysics of Galaxies · Physics 2023-05-31 Bo Huang , Ke Wang , Josep Miquel Girart , Wenyu Jiao , Qianru He , Enwei Liang

The dense cloud associated with W40, one of the nearby H II regions, has been studied in millimeter-wave molecular lines and in 1.2 mm continuum. Besides, 1280 MHz and 610 MHz interferometric observations have been done. The cloud has…

Astrophysics of Galaxies · Physics 2015-06-17 L. Pirogov , D. K. Ojha , M. Thomasson , Y. -F. Wu , I. Zinchenko

How mass is accumulated from cloud-scale down to individual stars is a key open question in understanding high-mass star formation. Here, we present the mass accumulation process in a hub-filament cloud G22 which is composed of four…

Color-color diagrams for the clump and interclump emission in 10 clump-cluster galaxies of the Ultra Deep Field are made from B,V,i, and z images and compared with models to determine redshifts, star formation histories, and galaxy masses.…

Astrophysics · Physics 2009-11-10 Bruce G. Elmegreen , Debra Meloy Elmegreen

We performed a multiwavelength study towards HII region Sh2-104. New maps of 12CO J=1-0 and 13CO J=1-0 were obtained from the Purple Mountain Observatory (PMO) 13.7 m radio telescope. Sh2-104 displays a double-ring structure. The outer ring…

Solar and Stellar Astrophysics · Physics 2017-11-15 Jin-Long Xu , Ye Xu , Naiping Yu , Chuan-peng Zhang , Xiao-Lan Liu , Jun-Jie Wang , Chang-Chun Ning , Bing-Gang Ju , Guo-Yin Zhang

We performed a multi-wavelength study toward the filamentary cloud G47.06+0.26 to investigate the gas kinematics and star formation. We present the 12CO (J=1-0), 13CO (J=1-0) and C18O (J=1-0) observations of G47.06+0.26 obtained with the…

Astrophysics of Galaxies · Physics 2018-01-10 Jin-Long Xu , Ye Xu , Chuan-Peng Zhang , Xiao-Lan Liu , Naiping Yu , Chang-Chun Ning , Bing-Gang Ju

The initial conditions of massive star and star cluster formation are expected to be cold, dense and high column density regions of the interstellar medium, which can reveal themselves via near, mid and even far-infrared absorption as…

We present a multi-wavelength study to probe the star formation (SF) processes on a larger scale (~1.05 deg x 0.56 deg) around the S242 site. The S242 molecular cloud is depicted in a velocity range from -3.25 to 4.55 km/s and has spatially…

Astrophysics of Galaxies · Physics 2017-08-23 L. K. Dewangan , T. Baug , D. K. Ojha , P. Janardhan , R. Devaraj , A. Luna

The Galactic star forming region in the southern sky, associated with IRAS 09002-4732 has been mapped simultaneously in two far infrared bands (148 & 209 um), with ~ 1' angular resolution. Fifteen sources including IRAS 08583-4719,…

Astrophysics · Physics 2007-05-23 S. K. Ghosh , B. Mookerjea , T. N. Rengarajan , S. N. Tandon , R. P. Verma

Infrared Dark Clouds (IRDCs) are unique laboratories to study the initial conditions of high-mass star and star cluster formation. We present high-sensitivity and high-angular resolution IRAM PdBI observations of N2H+ (1-0) towards IRDC…

Solar and Stellar Astrophysics · Physics 2014-03-07 Jonathan D. Henshaw , Paola Caselli , Francesco Fontani , Izaskun Jimenez-Serra , Jonathan C. Tan

High-angular resolution observations of dense molecular cores show that these cores can be clumpier at smaller scales, and that some of these clumps can also be unbound or transient. The use of chemical models of the evolution of the…

Astrophysics of Galaxies · Physics 2015-06-05 Oscar Morata , Josep Miquel Girart , Robert Estalella , Robin T. Garrod

We present observations of the intermediate to massive star-forming region I05345+3157 using the molecular line tracer CS(2-1) with CARMA to reveal the properties of the dense gas cores. Seven gas cores are identified in the integrated…

Solar and Stellar Astrophysics · Physics 2015-05-28 Katherine I. Lee , Leslie W. Looney , Randolf Klein , Shiya Wang

Stars are born from dense cores in molecular clouds. Observationally, it is crucial to capture the formation of cores in order to understand the necessary conditions and rate of the star formation process. The {\it Atacama Large Mm/sub-mm…

Astrophysics of Galaxies · Physics 2018-03-28 Shuo Kong , Jonathan C. Tan , Héctor G. Arce , Paola Caselli , Francesco Fontani , Michael J. Butler

We present Very Large Array observations of NH3 (1,1) and (2,2) in a sample of six infrared-dark clouds (IRDCs) with distances from 2 to 5 kpc. We find that ammonia serves as an excellent tracer of dense gas in IRDCs, showing no evidence of…

Astrophysics of Galaxies · Physics 2015-05-28 Sarah Ragan , Edwin Bergin , David Wilner

Infrared Dark Clouds (IRDCs) are cold, dense structures representative of the initial conditions of star formation. Many studies of IRDCs employ CO to investigate cloud dynamics. However, CO can be highly depleted from the gas phase in…