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Related papers: High-level ab initio quartic force fields and spec…

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Detecting anions in space has relied on a strong collaboration between theoretical and laboratory analyses to measure rotational spectra and spectroscopic constants to high accuracy. The advent of improved quantum chemical tools operating…

Earth and Planetary Astrophysics · Physics 2019-10-02 David Dubois , Ella Sciamma-O'Brien , Ryan Fortenberry

The synergy between high-resolution rotational spectroscopy and quantum-chemical calculations is essential for exploring future detection of molecules, especially when spectroscopy parameters are not available yet. By using highly…

Instrumentation and Methods for Astrophysics · Physics 2023-11-16 Natalia Inostroza-Pino , Valerio Lattanzi , C. Zachary Palmer , Ryan C. Fortenberry , Diego Mardones , Paola Caselli , Oko E. Godwin , Timothy J. Lee

Ammonia is one of the most widely observed molecules in space, and many observations are able to resolve the hyperfine structure due to the electric quadrupole moment of the nitrogen nucleus. The observed spectra often display anomalies in…

Astrophysics of Galaxies · Physics 2023-09-06 J. Loreau , A. Faure , F. Lique , S. Demes , P. J. Dagdigian

It has been shown that rotational lines observed in the Horsehead nebula PDR are probably not caused by l-C3H+, as was originally suggested. In the search for viable alternative candidate carriers, quartic force fields are employed here to…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 Ryan C. Fortenberry , Xinchuan Huang , T. Daniel Crawford , Timothy J. Lee

Many molecular species can presumably still be observed in space if they are adequately characterized chemically. In this paper, we suggest that this could be the case of the neutral (C$_4$N$^0$) and anion (C$_4$N$^-$) cyanopropynylidene…

Chemical Physics · Physics 2021-12-20 Ioan Baldea

(abridged) The fairly recent detection of a variety of anions in the Interstellar Molecular Clouds have underlined the importance of realistically modeling the processes governing their abundance. To this aim, our earlier calculations for…

Astrophysics of Galaxies · Physics 2016-11-03 F. A. Gianturco , T. Grassi , R. Wester

High precision spectrometry of galactic cosmic rays (CR) has revealed the lack of our understanding of how different CR elements are extracted from the supernova environments to be further accelerated in their shocks. Comparing the spectra…

High Energy Astrophysical Phenomena · Physics 2017-07-11 Adrian Hanusch , Tatyana Liseykina , Mikhail Malkov

Narrow optical resonances of atoms or molecules have immense significance in various precision measurements, such as testing fundamental physics and the generation of primary frequency standards. In these studies, accurate transition…

Atomic Physics · Physics 2022-10-13 Y. -N. Lv , A. -W. Liu , Y. Tan , C. -L. Hu , T. -P. Hua , X. -B. Zou , Y. R. Sun , C. -L. Zou , G. -C. Guo , S. -M. Hu

The AMS Collaboration has recently released data on cosmic ray (CR) leptons and hadrons that can shed light on two exciting problems in CR physics: on one side, the origin of the rise of the CR positron fraction above ~10 GeV of energy, on…

High Energy Astrophysical Phenomena · Physics 2015-11-02 Nicola Tomassetti

The observed spectrum of Galactic cosmic rays has several exciting features such as the rise in the positron fraction above ~10 GeV of energy and the spectral hardening of protons and helium at ~300 GeV/nucleon of energy. The ATIC-2…

High Energy Astrophysical Phenomena · Physics 2015-09-22 Nicola Tomassetti

Accurate spectroscopic constants and electrical properties of small molecules are determined by means of W4 and post-W4 theories. For a set of 28 first- and second-row diatomic molecules for which very accurate experimental spectroscopic…

Chemical Physics · Physics 2015-05-19 Amir Karton , Jan M. L. Martin

The unprecedented quality of the data collected by the AMS-02 experiment onboard the International Space Station allowed us to address subtle questions concerning the origin and propagation of cosmic rays. Here we discuss the implications…

High Energy Astrophysical Phenomena · Physics 2019-06-05 Carmelo Evoli , Roberto Aloisio , Pasquale Blasi

Next-generation neutrino oscillation experiments such as DUNE require percent-level knowledge of neutrino--nucleon interaction cross sections. The nucleon axial form factor $F_A(Q^2)$, parameterized by the axial mass $\MA$, is the dominant…

High Energy Physics - Phenomenology · Physics 2026-03-03 Guang Yang , Praveen Kumar

In the absence of laboratory data, state-of-the-art quantum chemical approaches can provide estimates of the binding energy (BE) of interstellar species with grains. Without BE values, contemporary astrochemical models are compelled to…

Large-scale self-consistent multiconfiguration Dirac--Hartree--Fock and relativistic configuration interaction calculations are reported for the $n \leq 6$ levels in Be-like ions from B II to Ne VII. Effects from electron correlation are…

Charge-current quasielastic (CCQE) (anti)neutrino scattering cross sections on a $^{12}$C target are analyzed using a spectral function $S(p,{\cal E})$ that gives a scaling function in accordance with the ($e,e'$) scattering data. The…

The ATIC balloon-borne experiment measures the energy spectra of elements from H to Fe in primary cosmic rays from about 100 GeV to 100 TeV. ATIC is comprised of a fully active bismuth germanate calorimeter, a carbon target with embedded…

The circumstellar ammonia (NH$_3$) chemistry in evolved stars is poorly understood. Previous observations and modelling showed that NH$_3$ abundance in oxygen-rich stars is several orders of magnitude above that predicted by equilibrium…

Solar and Stellar Astrophysics · Physics 2018-04-25 K. T. Wong , K. M. Menten , T. Kamiński , F. Wyrowski , J. H. Lacy , T. K. Greathouse

A first-principle theoretical approach to study the process of radiative electron attachment is developed and applied to the negative molecular ions CN$^-$, C$_4$H$^-$, and C$_2$H$^-$. Among these anions, the first two have already been…

For decades astronomers and astrophysicists believed that only positively charged ions were worthy of relevance in drawing the networks for possible chemical reactions in the interstellar medium, as well as in modeling the physical…

Chemical Physics · Physics 2012-09-14 Fabio Carelli
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