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Related papers: NH3 (1,1) hyperfine intensity anomalies in infall …

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We present 13 Type Ia supernovae (SNe Ia) observed in the restframe near-infrared (NIR) from 0.02 < z < 0.09 with the WIYN High-resolution Infrared Camera (WHIRC) on the WIYN 3.5-m telescope. With only 1-3 points per light curve and a prior…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Anja Weyant , W. Michael Wood-Vasey , Lori Allen , Peter M. Garnavich , Saurabh W. Jha , Richard Joyce , Thomas Matheson

Circumstellar envelopes (CSEs) of a variety of evolved stars have been found to contain ammonia (NH3) in amounts that exceed predictions from conventional chemical models by many orders of magnitude. The observations reported here were…

We present the results of the observations of the (J,K)=(1,1) and the (J,K)=(2,2) inversion transitions of the NH3 molecule toward a large sample of 40 regions with molecular or optical outflows, using the 37 m radio telescope of the…

Solar and Stellar Astrophysics · Physics 2015-05-27 I. Sepúlveda , G. Anglada , R. Estalella , R. López , J. M. Girart , J. Yang

The results are presented of a molecular line survey to search for the spectral signature of infall towards 77 850 micron continuum sources believed to be candidate high mass protostellar objects. Up to six different transitions, HCO+ 1-0,…

Astrophysics · Physics 2009-11-11 G. A. Fuller , S. J. Williams , T. K. Sridharan

The study of the physical and chemical properties of gas infall motion in the molecular clumps helps us understand the initial stages of star formation. We used the FTS wide-sideband mode of the IRAM 30-m telescope to observe nine infall…

Astrophysics of Galaxies · Physics 2022-11-29 Yang Yang , Yao Wang , Zhibo Jiang , Zhiwei Chen

Measurements of Type Ia Supernovae (SNe Ia) in the near-infrared (NIR) have been used both as an alternate path to cosmology compared to optical measurements and as a method of constraining key systematics for the larger optical studies.…

The hydroxyl radical (OH) is found in various environments within the interstellar medium (ISM) of the Milky Way and external galaxies, mostly either in diffuse interstellar clouds or in the warm, dense environments of newly formed low-mass…

Abridged abstract: For stars to form, material must fall inwards from core scales through the envelope towards the central protostar. The velocity profile around protostars is poorly constrained. 6 Class 0 protostars and one Class I…

Astrophysics of Galaxies · Physics 2015-06-17 J. C. Mottram , E. F. van Dishoeck , M. Schmalzl , L. E. Kristensen , R. Visser , M. R. Hogerheijde , S. Bruderer

We report high angular resolution observations, made with the Atacama Large Millimeter Array in band 6, of high excitation molecular lines of $\rm CH_3CN$ and $\rm SO_2$ and of the H29$\alpha$ radio recombination line towards the…

Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) 19-beam tracking observational mode, high sensitivity and high-velocity resolution HI spectral lines have been observed toward the high-mass star-forming region…

Astrophysics of Galaxies · Physics 2022-07-15 Li Yingjie , Xu Ye , Xu Jin-Long , Liu Dejian , Li Jingjing , Lin Zehao , Jiang Peng , Bian Shuaibo , Hao Chaojie , Chen Xiuhui

We have used the IRAM 30-m telescope to map some targets with HCO$^+$ (1-0) and H$^{13}$CO$^+$ (1-0) lines in order to search for gas infall evidence in the clumps. In this paper, we report the mapping results for 13 targets. All of these…

Astrophysics of Galaxies · Physics 2023-08-03 Yang Yang , Xi Chen , Zhibo Jiang , Zhiwei Chen , Shuling Yu , Jun Li

Type Ia Supernovae (SNe Ia) have been extensively used as standardisable candles in the optical for several decades. However, SNe Ia have shown to be more homogeneous in the near-infrared (NIR), where the effect of dust extinction is also…

We present new observations of the ultra-compact HII region G28.20-0.05 in 23 GHz continuum, and the NH3(1,1), NH3(2.2), and NH3(3,3) lines. To explain the complicated kinematics of the molecular gas, we propose a model consisting of two…

Astrophysics · Physics 2009-11-11 Peter K. Sollins , Qizhou Zhang , Eric Keto , Paul T. P Ho

We present high resolution (0.''12 x 0.''079) observations of the ultracompact HII region G10.6-0.4 in 23 GHz radio continuum and the NH3(3,3) line. Our data show that the infall in the molecular material is largely spherical, and does not…

Astrophysics · Physics 2009-11-10 Peter K. Sollins , Qizhou Zhang , Eric Keto , Paul T. P Ho

To better understand the physical properties of accretion disks in high-mass star formation, we present a study of a 12 high-mass accretion disk candidates observed at high spatial resolution with the Australia Telescope Compact Array…

Solar and Stellar Astrophysics · Physics 2014-11-20 H. Beuther , A. J. Walsh , S. N. Longmore

Gas accretion is a key process in star formation. However, the gas infall detections in high-mass star forming regions with high-spatial resolution observations are rare. Here we report the detection of gas infall towards a cometary…

Solar and Stellar Astrophysics · Physics 2013-10-11 Tie Liu , Yuefang Wu , Huawei Zhang

HCN is becoming a popular choice of molecule for studying star formation in both low- and high-mass regions and for other astrophysical sources from comets to high-redshift galaxies. However, a major and often overlooked difficulty with HCN…

Solar and Stellar Astrophysics · Physics 2013-05-08 R. M. Loughnane , M. P. Redman , M. A. Thompson , N. Lo , B. O'Dwyer , M. R Cunningham

We have used the Arecibo telescope to carry out an survey of 31 dark clouds in the Taurus/Perseus region for narrow absorption features in HI ($\lambda$ 21cm) and OH (1667 and 1665 MHz) emission. We detected HI narrow self--absorption…

Astrophysics · Physics 2009-11-07 Di Li , Paul F. Goldsmith

Hypervelocity stars are unique objects moving through the Milky Way at speeds exceeding the local escape velocity, providing valuable insights into the Galactic gravitational potential and the properties of its central supermassive black…