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Related papers: Variability in the CO ro-vibrational lines from HD…

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Submillimeter Array 1.3mm line and continuum observations toward the young massive star-forming region IRAS18182-1433 are presented. The data are complemented with short-spacing CO(2-1) observations and SiO(1-0) data from the VLA. Multiple…

Astrophysics · Physics 2009-11-11 H. Beuther , Q. Zhang , T. K. Sridharan , C. -F. Lee , L. A. Zapata

We present spectroscopic and imaging observations of the active T dwarf 2MASS 1237+6526, intended to investigate the emission mechanism of this cool brown dwarf. The H$\alpha$ emission line first detected in 1999 July appears to be…

Astrophysics · Physics 2009-11-07 Adam J. Burgasser , James Liebert , J. Davy Kirkpatrick , John E. Gizis

We discovered multiple high-velocity (ranging from -900 to -650 km/s) and narrow (FWHM = 15 km/s) absorption components corresponding to both the D2 and the D1 lines of Na I on a high dispersion spectrum of V1280 Sco observed on 2009 May 9…

Solar and Stellar Astrophysics · Physics 2015-05-14 Kozo Sadakane , Akito Tajitsu , Sahori Mizoguchi , Akira Arai , Hiroyuki Naito

This work aims to understand which midplane conditions are probed by the DCO$^+$ emission in the disk around the Herbig Ae star HD 169142. We explore the sensitivity of the DCO$^+$ formation pathways to the gas temperature and the CO…

We study the influence of convection on the asymmetries and Doppler shifts of Fe I spectral lines in the metal-poor red giant HD 122563. To this end, we compute theoretical Fe I line shifts and line bisectors using 3D hydrodynamical model…

Solar and Stellar Astrophysics · Physics 2013-03-28 J. Klevas , A. Kucinskas , H. -G. Ludwig , P. Bonifacio , M. Steffen , D. Prakapavicius

We present Atacama Large Millimeter/submillimeter Array (ALMA) observations in the dust continuum (690 GHz, 0.45 mm) and 12CO J=6-5 spectral line emission, of the transitional disks surrounding the stars SAO 206462 and SR 21. These ALMA…

Solar and Stellar Astrophysics · Physics 2015-06-18 Laura M. Pérez , Andrea Isella , John M. Carpenter , Claire J. Chandler

Different types of hot subdwarfs may have different origins, which will cause them to present different radial velocity (RV) variability properties. Only 6$\pm$4% of our single-lined He-rich hot subdwarfs that only show spectroscopic…

Solar and Stellar Astrophysics · Physics 2024-12-19 Ruijie He , Xiangcun Meng , Zhenxin Lei , Huahui Yan , Shunyi Lan

Using the Submillimeter Array we have detected the J=3-2 and 2-1 rotational transitions from within the first vibrationally excited state of CO toward the extreme carbon star IRC+10216 (CW Leo). The emission remains spatially unresolved…

To test theoretical models of massive star formation it is important to compare their predictions with observed systems. To this end, we conduct CO molecular line radiative transfer post-processing of 3D magneto-hydrodynamic (MHD)…

Astrophysics of Galaxies · Physics 2024-03-11 Duo Xu , Jonathan C. Tan , Jan E. Staff , Jon P. Ramsey , Yichen Zhang , Kei E. Tanaka

Aims: We study the characteristics of intermediate drift bursts (fibers) embedded in the July 14, 2000 large solar event. Methods: We used dynamic spectra from the acousto-optic analyzer (SAO) of the ARTEMIS-JLS solar radiospectrograph, in…

Solar and Stellar Astrophysics · Physics 2019-07-31 C. E. Alissandrakis , C. Bouratzis , A. Hillaris

(Abridged) Through spectrally unresolved observations of high-J CO transitions, Herschel-PACS has revealed large reservoirs of warm (300 K) and hot (700 K) molecular gas around low-mass protostars. We aim to shed light on the excitation and…

We present a novel approach to estimating the intensity mapping signal of any CO rotational line emitted during the Epoch of Reionization (EoR). Our approach is based on large velocity gradient (LVG) modeling, a radiative transfer modeling…

Astrophysics of Galaxies · Physics 2015-10-22 Natalie Mashian , Amiel Sternberg , Abraham Loeb

Filamentary structures are ubiquitous in observations of real molecular clouds, and also in simulations of turbulent, self-gravitating gas. However, making comparisons between observations and simulations is complicated by the difficulty of…

Astrophysics of Galaxies · Physics 2020-10-14 F. D. Priestley , A. P. Whitworth

Submillimeter lines of CN, NO, CO+ and SO+, and upper limits on SH+ and N2O are observed with the James Clerk Maxwell Telescope in two high-mass and up to nine low-mass young stellar objects and compared with chemical models. Constant…

Rotation-vibration spectra of the nitric acid molecule, HNO\3, are calculated for wavenumbers up to 7000~\cm. Calculations are performed using a Hamiltonian expressed in internal curvilinear vibrational coordinates solved using a hybrid…

Chemical Physics · Physics 2015-04-13 A. I. Pavlyuchko , S. N. Yurchenko , Jonathan Tennyson

Atmospheric carbon dioxide concentrations are being closely monitored by remote sensing experiments which rely on knowing line intensities with an uncertainty of 0.5% or better. We report a theoretical study providing rotation-vibration…

The gas temperature structure of protoplanetary disks is a key ingredient for interpreting various disk observations and for quantifying the subsequent evolution of these systems. The comparison of low- and mid-$J$ CO rotational lines is a…

Solar and Stellar Astrophysics · Physics 2016-06-22 D. Fedele , E. F. van Dishoeck , M. Kama , S. Bruderer , M. Hogerheijde

H$_{\rm I}$ 21-cm and $^{12}$CO 2.6-mm line emissions respectively trace the atomic and molecular gas phases, but they miss most of the opaque H$_{\rm I}$ and diffuse H$_2$ present in the Dark Neutral Medium (DNM) at the transition between…

High Energy Astrophysical Phenomena · Physics 2018-03-28 Q. Remy , I. A. Grenier , D. J. Marshall , J. M. Casandjian
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