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In preparation for future, large-scale, multi-object, high-resolution spectroscopic surveys of the Galaxy, we present a series of tests of the precision in radial velocity and chemical abundances that any such project can achieve at a 4m…

We present version 3.4 of the CalcHEP software package which is designed for effective evaluation and simulation of high energy physics collider processes at parton level. The main features of CalcHEP are the computation of Feynman…

High Energy Physics - Phenomenology · Physics 2015-06-05 Alexander Belyaev , Neil D. Christensen , Alexander Pukhov

We explore CO-CH4 quench kinetics in the atmospheres of substellar objects using updated time-scale arguments, as suggested by a thermochemical kinetics and diffusion model that transitions from the thermochemical-equilibrium regime in the…

Earth and Planetary Astrophysics · Physics 2015-05-28 Channon Visscher , Julianne I. Moses

Context. The MINCE (Measuring at Intermediate Metallicity Neutron-Capture Elements) project aims to provide high quality neutron-capture abundances measurements in several hundred stars at intermediate metallicity,-2.5 < [Fe/H] < -1.5. This…

Growing evidence has indicated that the global composition distribution plays an indisputable role in interpreting observational data. 3D general circulation models (GCMs) with a reliable treatment of chemistry and clouds are particularly…

Earth and Planetary Astrophysics · Physics 2022-08-10 Shang-Min Tsai , Elspeth K. H. Lee , Raymond Pierrehumbert

An accurate treatment of the multiphase interstellar medium (ISM) in hydrodynamic galaxy simulations requires that we follow not only the thermal evolution of the gas, but also the evolution of its chemical state, including its molecular…

Astrophysics of Galaxies · Physics 2015-06-18 Alexander J. Richings , Joop Schaye , Benjamin D. Oppenheimer

This paper presents the first results from a model for chemical evolution that can be applied to N-body cosmological simulations and quantitatively compared to measured stellar abundances from large astronomical surveys. This model…

Astrophysics of Galaxies · Physics 2015-09-29 Brian D. Crosby , Brian W. O'Shea , Timothy C. Beers , Jason Tumlinson

We introduce ECCOplanets, an open-source Python code that simulates condensation in the protoplanetary disk. Our aim is to analyse how well a simplistic model can reproduce the main characteristics of rocky planet formation. For this…

Earth and Planetary Astrophysics · Physics 2023-08-09 Anina Timmermann , Yutong Shan , Ansgar Reiners , Andreas Pack

We introduce FastPM, a highly-scalable approximated particle mesh N-body solver, which implements the particle mesh (PM) scheme enforcing correct linear displacement (1LPT) evolution via modified kick and drift factors. Employing a…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-14 Yu Feng , Man-Yat Chu , Uros Seljak , Patrick McDonald

We present the 4MOST-HR resolution Non-Local Thermal Equilibrium (NLTE) Payne artificial neural network (ANN), trained on $404\,793$ new FGK spectra with 16 elements computed in NLTE. This network will be part of the Stellar Abundances and…

Almost all planetary atmospheres are affected by disequilibrium chemical processes. In this paper we introduce our recently developed Chemical Kinetic Model (\texttt{ChemKM}). We show that the results of our HD189733b model are in good…

Earth and Planetary Astrophysics · Physics 2019-10-09 Karan Molaverdikhani , Thomas Henning , Paul Mollière

The standard gas mixture for the Resistive Plate Chambers (RPC), composed of C2H2F4/i-C4H10/SF6, allows the detector operation in avalanche mode, as required by the high-luminosity collider experiments. The gas density, the low current and…

Instrumentation and Detectors · Physics 2025-03-10 Giorgia Proto

Characterizing exoplanetary atmospheres via Bayesian retrievals requires assuming some chemistry model, such as thermochemical equilibrium or parameterized abundances. The higher-resolution data offered by upcoming telescopes enables more…

Earth and Planetary Astrophysics · Physics 2023-04-11 Michael D. Himes , Joseph Harrington , Atilim Gunes Baydin

We present an updated release of the BaSTI (a Bag of Stellar Tracks and Isochrones) stellar model and isochrone library for a solar scaled heavy element distribution. The main input physics changed from the previous BaSTI release include…

Astrophysics of Galaxies · Physics 2018-04-11 S. L. Hidalgo , A. Pietrinferni , S. Cassisi , M. Salaris , A. Mucciarelli , A. Savino , A. Aparicio , V. Silva Aguirre , K. Verma

We describe our contribution as industrial stakeholders to the existing open-source GPU4PySCF project (https: //github.com/pyscf/gpu4pyscf), a GPU-accelerated Python quantum chemistry package. We have integrated GPU acceleration into other…

We address disequilibrum abundances of some simple molecules in the atmospheres of solar composition brown dwarfs and self-luminous extrasolar giant planets using a kinetics-based 1D atmospheric chemistry model. Our approach is to use the…

Earth and Planetary Astrophysics · Physics 2015-06-22 Kevin J. Zahnle , Mark S. Marley

The study of the chemical composition of the interstellar medium (ISM) requires a strong synergy between laboratory astrophysics, modeling, and observations. In particular, astrochemical models have been developed for decades now and…

Astrophysics of Galaxies · Physics 2024-07-24 V. Wakelam , P. Gratier , J. -C. Loison , K. M. Hickson , J. Penguen , A. Mechineau

Chemical equilibrium considerations suggest that, assuming solar elemental abundances, carbon on HD 209458b is sequestered primarily as carbon monoxide (CO) and methane (CH4). The relative mole fractions of CO(g) and CH4(g) in chemical…

Astrophysics · Physics 2008-11-26 Curtis S. Cooper , Adam P. Showman

Defects are believed to play a fundamental role in the supersolid state of 4He. We report on studies by exact Quantum Monte Carlo (QMC) simulations at zero temperature of the properties of solid 4He in presence of many vacancies, up to 30…

Statistical Mechanics · Physics 2015-06-04 M. Rossi , L. Reatto , D. E. Galli

Chemistry plays an important role in the interstellar medium (ISM), regulating heating and cooling of the gas, and determining abundances of molecular species that trace gas properties in observations. Although solving the time-dependent…

Astrophysics of Galaxies · Physics 2019-04-05 Munan Gong , Eve C. Ostriker , Mark G. Wolfire