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Related papers: Modeling molecular hyperfine line emission

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Accurate line lists for three molecules, BeH, MgH and CaH, in their ground electronic states are presented. These line lists are suitable for temperatures relevant to exoplanetary atmospheres and cool stars (up to 2000K). A combination of…

Solar and Stellar Astrophysics · Physics 2012-08-22 Benjamin Yadin , Thomas Veness , Pierandrea Conti , Christian Hill , Sergei N. Yurchenko , Jonathan Tennyson

We introduce a new stacking method in Keplerian disks that (1) enhances signal-to-noise ratios (S/N) of detected molecular lines and (2) that makes visible otherwise undetectable weak lines. Our technique takes advantage of the Keplerian…

Solar and Stellar Astrophysics · Physics 2016-12-14 Hsi-Wei Yen , Patrick M. Koch , Hauyu Baobab Liu , Evaria Puspitaningrum , Naomi Hirano , Chin-Fei Lee , Shigehisa Takakuwa

The transport approach is a useful tool to study dynamics of non-equilibrium systems. For heavy-ion collisions at intermediate energies, where both the smooth nucleon potential and the hard-core nucleon-nucleon collision are important, the…

Nuclear Theory · Physics 2019-04-02 Jun Xu

In this article we present a machine learning model to obtain fast and accurate estimates of the molecular Hessian matrix. In this model, based on a random forest, the second derivatives of the energy with respect to redundant internal…

Chemical Physics · Physics 2024-01-10 Giorgio Domenichini , Christoph Dellago

Computing resonance and anti-resonance backbone curves in complex nonlinear mechanical systems is of high engineering relevance but remains computationally challenging, especially for large finite-element (FE) models. Existing…

Classical Physics · Physics 2026-02-09 Wei Wen , Weikai Qi , Weidong Wen

High-precision measurements in neutrino oscillation experiments require a very accurate description of the lepton-nucleus scattering process. Several cross-section calculations are available, but important discrepancies are still present…

Nuclear Theory · Physics 2024-01-12 Valerio Belocchi , Maria Benedetta Barbaro , Arturo De Pace , Marco Martini

Aims. Excitation of far-infrared and submillimetric molecular lines may originate from nonreactive collisions, chemical formation, or far infrared, near-infrared, and optical fluorescences. As a template, we investigate the impact of each…

Astrophysics of Galaxies · Physics 2015-06-12 Benjamin Godard , José Cernicharo

Motional Stark effect (MSE) spectroscopy represents a unique diagnostic tool capable of determining the magnitude of the magnetic field and its direction in the core of fusion plasmas. The primary excitation channel for fast hydrogen atoms…

Atomic Physics · Physics 2020-03-06 Oleksandr Marchuk , David R. Schultz , Yuri Ralchenko

Inelastic processes rate coefficients for low-energy Sr + H, Sr$^+$ + H$^-$, Sr$^+$ + H and Sr$^{2+}$ + H$^-$ collisions are calculated using multichannel quantum model approach. 31 scattering channels of SrH$^+$ and 17 scattering channels…

Atomic Physics · Physics 2022-03-17 Svetlana A. Yakovleva , Andrey K. Belyaev , Lyudmila I. Mashonkina

We present an approximate energy-integration method for identifying collisional neutrino flavor instabilities. Direct evaluation of the dispersion relation requires multi-dimensional integrals over neutrino phase space, making systematic…

High Energy Astrophysical Phenomena · Physics 2026-04-02 Jiabao Liu , Hiroki Nagakura

Sub-millimetre dust emission is often used to derive the column density N of dense interstellar clouds. The observations consist of data at several wavelengths but of variable resolution. We examine two procedures that been proposed for the…

Astrophysics of Galaxies · Physics 2015-06-15 M. Juvela , J. Malinen , T. Lunttila

Aims: Our aim is to identify the dominant molecular cooling lines and characteristic emission features in the 1.3 mm window of distinct regions in the northern part of the Orion A molecular cloud. By defining and analysing template regions,…

Astrophysics of Galaxies · Physics 2020-04-15 N. Brinkmann , F. Wyrowski , J. Kauffmann , D. Colombo , K. M. Menten , X. D. Tang , R. Güsten

The electron emission pattern of transfer-ionization in collisions of He$^{2+}$ with He was investigated for impact velocities between 0.53 a.u. and 0.77 a.u. (7 keV/u - 15 keV/u) employing recoil-ion momentum spectroscopy. This process is…

Atomic Physics · Physics 2022-01-26 L. Ph. H. Schmidt , M. S. Schöffler , C. Goihl , T. Jahnke , H. Schmidt-Böcking , R. Dörner

Shocks, modelled over a broad range of parameters, are used to construct a new tool to deduce the mechanical energy and physical conditions from observed atomic or molecular emission lines. We compute magnetised, molecular shock models with…

Astrophysics of Galaxies · Physics 2022-03-14 Andrew Lehmann , Benjamin Godard , Gillaume Pineau des Forêts , Alba Vidal-García , Edith Falgarone

Using high-resolution (~85000) and high signal-to-noise ratio (~200) optical spectra acquired with the European Southern Observatory Ultraviolet and Visual Echelle Spectrograph, we have determined the interstellar column densities of C2 for…

Astrophysics of Galaxies · Physics 2010-09-28 M. Kazmierczak , M. R. Schmidt , A. Bondar , J. Krelowski

Aims: Hydrogen and helium line spectra are crucial diagnostic features for the quantitative analysis of OB stars. We compute synthetic spectra based on a hybrid non-LTE approach in order to test the ability of these models to reproduce…

Astrophysics · Physics 2009-11-11 M. F. Nieva , N. Przybilla

An angle-resolved x-ray spectroscopic scheme is presented for determining the hyperfine splitting of highly charged ions. For helium-like ions, in particular, we propose to measure either the angular distribution or polarization of the…

Atomic Physics · Physics 2017-07-12 Z. W. Wu , A. V. Volotka , A. Surzhykov , S. Fritzsche

In this study, we perform detailed spectroscopic modeling to analyze the interaction of circumstellar material (CSM) with ejecta in both hydrogen-rich and hydrogen-poor superluminous supernovae (SLSNe), systematically varying properties…

High Energy Astrophysical Phenomena · Physics 2025-01-07 Gururaj A. Wagle , Emmanouil Chatzopoulos , Michael J. Baer

A simple method for the extraction of the times of maximal emission for kaons and pions using the combined fitting of their transverse momentum spectra and the longitudinal interferometry radii dependencies on the pair transverse mass $m_T$…

Nuclear Theory · Physics 2021-10-27 V. M. Shapoval , Yu. M. Sinyukov

We present results from a program of optical spectroscopy for 23 nearby galaxy emission-line nuclei. This investigation takes advantage of the spatial resolution of the Hubble Space Telescope to study the structure and energetics of the…