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

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We analyze line-of-sight atomic hydrogen (HI) line profiles of 31 nearby, low-mass galaxies selected from the Very Large Array - ACS Nearby Galaxy Survey Treasury (VLA-ANGST) and The HI Nearby Galaxy Survey (THINGS) to trace regions…

We analyzed both HCN J=1-0 and HNC J=1-0 line profiles to study the inflow motions in different evolutionary stages of massive star formation: 54 infrared dark clouds (IRDCs), 69 high-mass protostellar object (HMPOs), and 54 ultra-compact…

Astrophysics of Galaxies · Physics 2016-08-17 Mihwa Jin , Jeong-Eun Lee , Kee-Tae Kim , Neal J. Evans

This paper outlines a way to determine the ICF using only infrared data. We identify four line pairs, [NeIII] 36$\micron$/[NeII] 12.8$\micron$, [NeIII]~15.6$\micron$ /[NeII] 12.8$\micron$, [ArIII] 9$\micron$/[ArII] 6.9$\micron$, and [ArIII]…

The young stellar source HH 30 is a textbook example of an ionic optical jet originating from a disk in an edge-on system shown by the HST. It has a remnant envelope in $^{12}$CO observed by ALMA. The optical jet is characterized by its…

Solar and Stellar Astrophysics · Physics 2024-02-06 Tsung-Han Ai , Chun-Fan Liu , Hsien Shang , Doug Johnstone , Ruben Krasnopolsky

We present a 21cm line HI self-absorption (HISA) survey of cold atomic gas within Galactic longitudes 75 to 146 degrees and latitudes -3 to +5 degrees. We identify HISA as spatially and spectrally confined dark HI features and extract it…

We have discovered 16 Type Ia supernovae (SNe Ia) with the Hubble Space Telescope (HST) and have used them to provide the first conclusive evidence for cosmic deceleration that preceded the current epoch of cosmic acceleration. These…

The HIFI instrument on board the Herschel Space Observatory has been used to observe interstellar nitrogen hydrides along the sight-line towards G10.6-0.4 in order to improve our understanding of the interstellar chemistry of nitrogen. We…

Context. The high energies of protostellar jets, implied by recent observations of X-rays from such flows, came very much as a surprise. Inferred shock velocities are considerably higher than what was previously known, hence putting even…

Astrophysics · Physics 2009-11-11 R. Liseau

Optical spectroscopy offers the most direct view of the stellar properties and the accretion indicators. Standard accretion tracers, such as $H\beta$, $H\alpha$, and, Ca II triplet lines, and most photospheric features, fall in the optical…

Based on the Gaia DR2 catalogue of hot subdwarf star candidates, we identified 1587 hot subdwarf stars with spectra in LAMOST DR7. We present atmospheric parameters for these stars by fitting the LAMOST spectra with {\sc Tlusty/Synspec}…

Solar and Stellar Astrophysics · Physics 2021-09-29 Yangping Luo , Peter Nemeth , Kun Wang , Xi Wang , Zhanwen Han

Spectral line and continuum observations of the ionized and molecular gas in G20.08-0.14 N explore the dynamics of accretion over a range of spatial scales in this massive star-forming region. Very Large Array observations of NH_3 at 4''…

Astrophysics of Galaxies · Physics 2015-05-14 Roberto Galván-Madrid , Eric Keto , Qizhou Zhang , Stan Kurtz , Luis F. Rodríguez , Paul T. P. Ho

Absorption features in stellar atmospheres are often used to calibrate photocentric velocities for kinematic analysis of further spectral lines. The Li feature at $\sim$ 6708 {\AA} is commonly used, especially in the case of young stellar…

Direct observations of accretion disks around high-mass young stellar objects would help to discriminate between different models of formation of massive stars. However, given the complexity of massive star forming regions, such studies are…

Solar and Stellar Astrophysics · Physics 2015-05-27 S. Leurini , C. Codella , L. Zapata , M. T. Beltran , P. Schilke , R. Cesaroni

Astrometric microlensing is a unique tool to measure stellar masses. It allows us to determine the mass of the lensing star with an accuracy of a few per cent. In this paper, we update, extend, and refine our predictions of…

Solar and Stellar Astrophysics · Physics 2022-03-30 Jonas Klüter , Ulrich Bastian , Markus Demleitner , Joachim Wambsganss

Although gravitational collapse is supposed to play an essential role in the star formation process, infall motions have been always elusive to detect. So far, only a few observational signatures have been commonly used to claim for the…

Solar and Stellar Astrophysics · Physics 2015-06-17 J. M. Mayen-Gijon , G. Anglada , M. Osorio , L. F. Rodriguez , S. Lizano , J. F. Gomez , C. Carrasco-Gonzalez

We analyze a set of 89 Type Ia supernovae (SN Ia) that have both optical and near-infrared (NIR) photometry to derive distances and construct low redshift ($z < 0.04$) Hubble diagrams. We construct mean light curve (LC) templates using a…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Arturo Avelino , Andrew S. Friedman , Kaisey S. Mandel , David O. Jones , Peter J. Challis , Robert P. Kirshner

We present the HI galaxy observation results of the FATHOMER (FAst neuTral HydrOgen intensity Mapping ExpeRiment), a pilot drift scan survey by the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The survey comprises 28 hours…

Astrophysics of Galaxies · Physics 2026-03-23 Shuanghao Shu , Yichao Li , Wenxiu Yang , Jiaxin Wang , Wenkai Hu , Furen Deng , Shifan Zuo , Yougang Wang , Xuelei Chen

We present positions, proper motions, and near-infrared photometry for 966 known objects with spectral types later than M observed as part of the the UKIRT Hemisphere Survey (UHS). We augment the photometry and astrometry from UHS with…

Protostellar outflows are considered a signpost of star formation. These outflows can cause shocks in the molecular gas and are typically traced by the line wings of certain molecules. HNCO (4--3) has been regarded as a shock tracer because…

Astrophysics of Galaxies · Physics 2023-06-07 Jinjin Xie , Juan Li , Junzhi Wang , Shu Liu , Kai Yang , Donghui Quan , Siqi Zheng , Yuqiang Li , Jingwen Wu , Yan Duan , Di Li
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