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Related papers: Structure of the W3A Low Density Foreground Region

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A study of 12 ultracompact HII regions was conducted to probe the physical conditions and kinematics in the inner envelopes of the molecular clumps harboring them. The APEX telescope was used to observe the sources in the CO (4-3) and 13CO…

Astrophysics · Physics 2009-11-11 F. Wyrowski , S. Heyminck , R. Guesten , K. M. Menten

We investigate the physical structure of the gas component of the disk around the pre-main-sequence star HD169142. The 13CO and C18O J=2-1 line emission is observed from the disk with 1.4'' resolution using the Submillimeter Array. We adopt…

Astrophysics · Physics 2008-06-12 Olja Panić , Michiel R. Hogerheijde , David Wilner , Chunhua Qi

We are presenting here a follow-up study of the molecular gas and dust in the environs of the star forming region NGC 3503. This study aims at dealing with the interaction of NGC 3503 with its parental molecular cloud, and also with the…

Astrophysics of Galaxies · Physics 2014-05-08 N. U. Duronea , J. Vasquez , G. A. Romero , C. E. Cappa , R. Barbá , L. Bronfman

Ions and electrons play an important role in various stages of the star formation process. By following the magnetic field of their environment and interacting with neutral species, they slow down the gravitational collapse of the…

Solar and Stellar Astrophysics · Physics 2018-05-02 D. Quénard , S. Bottinelli , E. Caux , V. Wakelam

Gas plays a major role in the dynamical evolution of young stellar objects. Its interaction with the dust is the key to our understanding planet formation later on in the protoplanetary disc stage. Studying the gas content is a crucial step…

Solar and Stellar Astrophysics · Physics 2016-10-19 Pablo Rivière Marichalar , Bruno Merín , Inga Kamp , Carlos Eiroa , Benjamín Montesinos

More complete knowledge of galaxy evolution requires understanding the process of star formation and interaction between the interstellar radiation field and the interstellar medium in galactic environments traversing a wide range of…

The spectral energy distribution (SED) in the millimetre (mm) to centimetre (cm) range is a useful tool for characterising the dust in protostellar envelopes as well as free-free emission from the protostar and outflow. While many studies…

Astrophysics of Galaxies · Physics 2021-09-22 M. Bouvier , A. López-Sepulcre , C. Ceccarelli , N. Sakai , S. Yamamoto , Y-L. Yang

We model Carbon Recombination Line (CRL) emission from the Photo Dissociation Region (PDR) surrounding the Ultra-Compact (UC) HII region W48A. Our modelling shows that the inner regions ($A_V \sim 1$) of the CII layer in the PDR contribute…

Astrophysics of Galaxies · Physics 2015-06-16 S. Jeyakumar , D. Anish Roshi

High-resolution images of the hypercompact HII regions (HCHII) in W3 IRS 5 taken with the Very Large Array (VLA) at 1.3 and 0.7 cm are presented. Four HCHII regions were detected with sufficient signal-to-noise ratios to allow the…

Astrophysics · Physics 2009-11-10 T. L. Wilson , D. A. Boboltz , R. A. Gaume , S. T. Megeath

We have explored the nature of the extended emission-line region around the z=0.37 quasar 4C 37.43, using extensive ground-based and HST imaging and spectroscopy. The velocity field of the ionized gas shows gradual gradients within…

Astrophysics · Physics 2009-11-07 Alan Stockton , John W. MacKenty , Esther M. Hu , Tae-Sun Kim

Tracing dust in small dense molecular cores is a powerful tool to study the conditions required for ices to form during the pre-stellar phase. To study these environments, five molecular cores were observed: three with ongoing low-mass star…

Astrophysics of Galaxies · Physics 2021-09-08 Laurie E. U. Chu , Klaus W. Hodapp

We present a new high-resolution study of pre-protocluster regions in tracers exclusively probing the coldest and dense gas (NH_2D). The data are used to constrain the chemical, thermal, kinematic, and physical conditions (i.e., densities)…

Astrophysics of Galaxies · Physics 2015-05-28 T. Pillai , J. Kauffmann , F. Wyrowski , J. Hatchell , A. G. Gibb , M. A. Thompson

We present molecular line observations of 13CO and C18O J=3-2, CN N = 3 - 2, and CS J=7-6 lines in the protoplanetary disk around TW Hya at a high spatial resolution of ~9 au (angular resolution of 0.15''), using the Atacama Large…

The Orion molecular cloud complex harbours the nearest GMCs and site of high-mass star formation. Its YSO populations are thoroughly characterized. The region is therefore a prime target for the study of star formation. Here, we verify the…

Recent ALMA measurements have revealed bright OIII 88 micron line emission from galaxies during the Epoch of Reionization (EoR) at redshifts as large as $z \sim 9$. We introduce an analytic model to help interpret these and other upcoming…

Astrophysics of Galaxies · Physics 2020-10-07 Shengqi Yang , Adam Lidz

We present a detailed characterization of the population of compact radio-continuum sources in W51 A using subarcsecond VLA and ALMA observations. We analyzed their 2-cm continuum, the recombination lines (RL's) H77$\alpha$ and H30$\alpha$,…

Astrophysics of Galaxies · Physics 2020-08-26 Rudy Rivera-Soto , Roberto Galván-Madrid , Adam Ginsburg , Stan Kurtz

We present the first detection of a jet in the far-IR [O I] lines from an intermediate mass protostar. We have carried out a Herschel/PACS spectral mapping study in the [O I] lines of OMC-2 FIR 3 and FIR 4, two of the most luminous…

Mon R2, at a distance of 830 pc, is the only ultracompact HII region (UC HII) where the photon-dominated region (PDR) between the ionized gas and the molecular cloud can be resolved with Herschel. HIFI observations of the abundant compounds…

Intensity mapping provides a unique means to probe the epoch of reionization (EoR), when the neutral intergalactic medium was ionized by the energetic photons emitted from the first galaxies. The [CII] 158$\mu$m fine-structure line is…

ABRIDGED: A detailed 2D study of the central region of NGC5253 has been performed to characterize the stellar and ionized gas structure as well as the extinction distribution, physical properties and kinematics of the ionized gas in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 A. Monreal-Ibero , J. M. Vilchez , J. R. Walsh , C. Munoz-Tunon