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We present new 2 cm and 6 cm maps of H2CO, radio recombination lines, and the radio continuum in the W51 star forming complex acquired with Arecibo and the Green Bank Telescope at ~50" resolution. We use H2CO absorption to determine the…

We present the results of an extensive Arecibo observational survey of magnetic field strengths in the inter-core regions of molecular clouds to determine their role in the evolution and collapse of molecular clouds as a whole. Sensitive 18…

Astrophysics of Galaxies · Physics 2019-10-16 K. L. Thompson , T. H. Troland , C. Heiles

Using the IRAM 30 m telescope, we presented observations of N2H+ J = 1-0, CCS JN = 87-76 and 77-66 lines toward a large sample of ultracompact HII regions (UC HIIs). Among our 88 UC HIIs, 87 and 33 sources were detected in the N2H+ J = 1-0…

Astrophysics of Galaxies · Physics 2025-05-30 J. L. Chen , J. S. Zhang , J. X. Ge , Y. X. Wang , H. Z. Yu , Y. P. Zou , Y. T. Yan , X. Y. Wang , D. Y. Wei

We report column densities of molecular gas in the W5 star-forming region as traced with OH 18-cm emission in a grid survey using the Green Bank Telescope. OH appears to trace a greater column density than does CO in 8 out of 15 cases…

Astrophysics of Galaxies · Physics 2019-03-27 Philip D. Engelke , Ronald J. Allen

We present the results of a targeted 3-mm spectral line survey towards the eighty-three 6.67 GHz methanol maser selected star forming clumps observed by Purcell et al. 2006. In addition to the previously reported measurements of HCO+ (1 -…

We have conducted a mapping spectral line survey toward the Galactic giant molecular cloud W51 in the 3 mm band with the Mopra 22 m telescope in order to study an averaged chemical composition of the gas extended over a molecular cloud…

We present results obtained towards the HII regions N159, N166, and N132 from the emission of several molecular lines in the 345 GHz window. Using ASTE we mapped a 2.4' $\times$ 2.4' region towards the molecular cloud N159-W in the…

Astrophysics of Galaxies · Physics 2015-11-11 S. Paron , M. E. Ortega , C. Fariña , M. Cunningham , P. A. Jones , M. Rubio

We have observed several emission lines of two Nitrogen-bearing (C2H5CN and C2H3CN) and two Oxygen-bearing (CH3OCH3 and HCOOCH3) molecules towards a sample of well-known hot molecular cores (HMCs) in order to check whether the chemical…

Astrophysics · Physics 2009-11-13 F. Fontani , I. Pascucci , P. Caselli , F. Wyrowski , R. Cesaroni , C. M. Walmsley

We present the results of NH3 (1,1), (2,2) and (3,3) and H2O maser simultaneous mapping observations toward the high-mass star-forming region W33 with the Nobeyama 45-m radio telescope. W33 has six dust clumps and one of which, W33 Main, is…

The polarized emission of astrophysical masers, especially OH and methanol lines, is an effective tool to study the magnetic field in high-mass star-forming regions. The magnetic field strength measurement via the Zeeman effect of OH maser…

Astrophysics of Galaxies · Physics 2025-08-21 A. Kobak , G. Surcis , A. Bartkiewicz , W. H. T. Vlemmings , M. Szymczak

Cosmic rays (CRs) have strong influences on the chemistry of dense molecular clouds (MCs). To study the detailed chemistry induced by CRs, we conducted a Yebes W band line survey towards an unshocked MC (which we named as 3C391:NML)…

Astrophysics of Galaxies · Physics 2024-08-28 Tian-Yu Tu , Prathap Rayalacheruvu , Liton Majumdar , Yang Chen , Ping Zhou , Miguel Santander-García

Here we present high spatial resolution (<1 arcsecond) observations of molecular emission in Orion-KL conducted using the Combined Array for Research in Millimeter-Wave Astronomy (CARMA). This work was motivated by recent millimeter…

Astrophysics of Galaxies · Physics 2015-06-05 Susanna L. Widicus Weaver , Douglas N. Friedel

We present high angular resolution ($\sim$ 3$''$) and sensitive 1.3 mm continuum, cyanogen (CN) and vinyl cyanide (C$_2$H$_3$CN) line observations made with the Submillimeter Array (SMA) toward one of most highly obscured objects of the W51…

We present 1" resolution CARMA observations of the 3mm continuum and 95 GHz methanol masers toward 14 candidate high mass protostellar objects (HMPOs). Dust continuum emission is detected toward seven HMPOs, and methanol masers toward 5…

Astrophysics of Galaxies · Physics 2011-02-11 S. Schnee , J. Carpenter

We present new, wide and deep images in the 1.1 mm continuum and the $^{12}$CO ($J$=1-0) emission toward the northern part of the Orion A Giant Molecular Cloud (Orion-A GMC). The 1.1 mm data were taken with the AzTEC camera mounted on the…

Absorption lines from the molecules OH+, H2O+, and H3+ have been observed in a diffuse molecular cloud along a line of sight near W51 IRS2. We present the first chemical analysis that combines the information provided by all three of these…

Astrophysics of Galaxies · Physics 2015-06-11 Nick Indriolo , D. A. Neufeld , M. Gerin , T. R. Geballe , J. H. Black , K. M. Menten , J. R. Goicoechea

The first observations of the recently completed Wisconsin H-Alpha Mapper (WHAM) facility include a study of emission lines from high velocity clouds in the M, A, and C complexes, with most of the observations on the M I cloud. We present…

Astrophysics · Physics 2009-10-30 S. L. Tufte , R. J. Reynolds , L. M. Haffner

We present new high-sensitivity high-resolution mm-wave observations of the Onsala 1 ultra-compact HII region that bring to light the internal structure of this massive star forming cloud. The 1.2 mm continuum map obtained with the IRAM…

Astrophysics · Physics 2009-11-10 M. S. N. Kumar , M. Tafalla , R. Bachiller

We present aperture synthesis imaging of dense molecular gas in the Large Magellanic Cloud, taken with the prototype millimeter receivers of the Australia Telescope Compact Array (ATCA). Our observations of the N113 HII region reveal a…

Astrophysics · Physics 2019-08-14 Tony Wong , John B. Whiteoak , Juergen Ott , Yi-nan Chin , Maria R. Cunningham

We present 12mm Mopra observations of dense molecular gas towards the W28 supernova remnant (SNR) field. The focus is on the dense molecular gas towards the TeV gamma-ray sources detected by the H.E.S.S. telescopes, which likely trace the…

Astrophysics of Galaxies · Physics 2015-05-20 B. Nicholas , G. Rowell , M. G. Burton , A. Walsh , Y. Fukui , A. Kawamura , S. Longmore , E. Keto