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Related papers: A variationally computed line list for hot NH3

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We report the detection of the (J,K) = (1,1), (2,2), and (3,3) inversion lines of ammonia (NH3) towards the south--western molecular lobe in M82. The relative intensities of the ammonia lines are characterized by a rotational temperature of…

Astrophysics · Physics 2009-11-06 A. Weiss , N. Neininger , C. Henkel , J. Stutzki , U. Klein

Auroral lines enable accurate measurements of chemical abundances in ionized gaseous nebulae thanks to their sensitivity to electron temperature. However, metal-enriched systems remain a challenge, as even deep observations cannot retrieve…

In the first section we present the atomic part where a C2+ atomic target was prepared and used to generate theoretical data to investigate recombination lines arising from electron-ion collisions in thin plasma. R-matrix method was used to…

Atomic Physics · Physics 2012-11-07 Taha Sochi

A spectral survey of methyl acetylene (CH3CCH) was conducted toward the hot molecular core/outflow G331.512-0.103. Our APEX observations allowed the detection of 41 uncontaminated rotational lines of CH3CCH in the frequency range between…

Transition intensities for small molecules such as water and CO$_2$ can now be computed with such high accuracy that they are being used to systematically replace measurements in standard databases. These calculations use high accuracy ab…

We present the $H$-band spectral line lists adopted by the Apache Point Observatory Galactic Evolution Experiment (APOGEE). The APOGEE line lists comprise astrophysical, theoretical, and laboratory sources from the literature, as well as…

Accurate rotation-vibration line lists for two molecules, NaCl and KCl, in their ground electronic states are presented. These line lists are suitable for temperatures relevant to exoplanetary atmospheres and cool stars (up to 3000 K).…

Quantum mechanical tunneling inversion transition in ammonia NH3 is actively used as a sensitive tool to study possible variations of the electron-to-proton mass ratio, mu = m_e/m_p. The molecule H3O+ has the inversion barrier significantly…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 M. G. Kozlov , S. A. Levshakov

Quantitative analyses of extreme helium stars to date face the difficulty that theory fails to reproduce the observed helium lines in their entirety, wings and line cores. Here, we demonstrate how the issues can be resolved using…

Astrophysics · Physics 2007-05-23 N. Przybilla , K. Butler , U. Heber , C. S. Jeffery

The temperature is a central parameter affecting the chemical and physical properties of dense cores of interstellar clouds and their evolution to star formation. The chemistry and the dust properties are temperature dependent and the…

Astrophysics of Galaxies · Physics 2015-06-03 M. Juvela , J. Harju , N. Ysard , T. Lunttila

Molecular line-transition lists are an essential ingredient for radiative-transfer calculations. With recent databases now surpassing the billion-lines mark, handling them has become computationally prohibitive, due to both the required…

Earth and Planetary Astrophysics · Physics 2017-11-29 Patricio Cubillos

We present survey data of the NH3 (J, K) = (1, 1)--(6, 6) lines, simultaneously observed with the Tsukuba 32-m telescope, in the main part of the central molecular zone of the Galaxy. The total number of on-source positions was 2655. The…

Published high-resolution rotation-vibration transitions of \spec{h212c16o}, the principal isotopologue of methanal, are analyzed using the MARVEL (Measured Active Rotation-Vibration Energy Levels) procedure. The literature results are…

The equation of state (EOS) of materials at warm dense conditions poses significant challenges to both theory and experiment. We report a combined computational, modeling, and experimental investigation leveraging new theoretical and…

An accurate line list for calcium oxide is presented covering transitions between all bound ro-vibronic levels from the five lowest electronic states \X, \Ap, \A, \astate, and \bstate. The ro-vibronic energies and corresponding…

Astrophysics of Galaxies · Physics 2016-07-05 Sergei N. Yurchenko , Audra Blissett , Usama Asari , Marcus Vasilios , Christian Hill , Jonathan Tennyson

We present new or improved methods for calculating NLTE, line-blanketed model atmospheres for hot stars with winds (spectral types A to O), with particular emphasis on a fast performance. These methods have been implemented into a previous,…

Astrophysics · Physics 2009-11-10 J. Puls , M. A. Urbaneja , R. Venero , T. Repolust , U. Springmann , A. Jokuthy , M. R. Mokiem

We report on calculations of energy levels, radiative rates, oscillator strengths, and line strengths for transitions among the lowest 253 levels of the (1s$^2$2s$^2$2p$^6$) 3s$^2$3p$^5$, 3s3p$^6$, 3s$^2$3p$^4$3d, 3s3p$^5$3d,…

Atomic Physics · Physics 2013-07-10 KM Aggarwal , FP Keenan , AZ Msezane

Improved opacities are needed for modelling the atmospheres and evolution of cool carbon-rich stars and extra-solar planets; in particular, contributions made by the astrophysically important propadienediylidene (C$_3$) molecule need, at a…

Solar and Stellar Astrophysics · Physics 2024-10-25 A. E. Lynas-Gray , O. L. Polyansky , J. Tennyson , S. N. Yurchenko , N. F. Zobov

The rotationally resolved spectrum of the A ^1Pi_u <- X ^1Sigma^+_g 000-000 transition of C3, centered at 4051.6A, has been observed along 10 translucent lines of sight. To interpret these spectra, a new method for the determination of…

Astrophysics · Physics 2009-11-07 Mate Adamkovics , Geoffrey A. Blake , Benjamin J. McCall

Transition wavelengths and rates are given for E1, E2, M1, and M2 transitions between singlet and triplet S, P, D, and F states in heliumlike ions of astrophysical interest: carbon, nitrogen, oxygen, neon, silicon, and argon. All possible…

Astrophysics · Physics 2009-11-07 I. M. Savukov , W. R. Johnson , U. I. Safronova
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