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Polarization properties of high energy photodisintegration of the deuteron are studied within the framework of the hard rescattering mechanism~(HRM). In HRM, a quark of one nucleon knocked-out by the incoming photon rescatters with a quark…

Nuclear Theory · Physics 2009-11-10 Misak M. Sargsian

We present the first simulations evolving resolved spectra of cosmic rays (CRs) from MeV-TeV energies (including electrons, positrons, (anti)protons, and heavier nuclei), in live kinetic-MHD galaxy simulations with star formation and…

High Energy Astrophysical Phenomena · Physics 2023-08-29 Philip F. Hopkins , Iryna S. Butsky , Georgia V. Panopoulou , Suoqing Ji , Eliot Quataert , Claude-Andre Faucher-Giguere , Dusan Keres

The linear polarization of the characteristic photon emission from few-electron ions is studied for its sensitivity with regard to the nuclear spin and magnetic moment of the ions. Special attention is paid, in particular, to the…

Nuclear Theory · Physics 2013-06-04 Andrey Surzhykov , Yuri A. Litvinov , Thomas Stöhlker , Stephan Fritzsche

Lyman-$\alpha$ photons enable the cosmic dawn 21-cm signal through a process called the Wouthuysen-Field effect. An accurate model of the signal in this epoch hinges on the accuracy of the computation of the Ly$\alpha$ coupling, which…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-18 Shikhar Mittal , Girish Kulkarni , Thibault Garel

We explore the effects arising due to the coupling of the center of mass and relative motion of two charged particles confined on an inhomogeneous helix with a locally modified radius. It is first proven that a separation of the center of…

Classical Physics · Physics 2015-06-03 A. V. Zampetaki , J. Stockhofe , S. Krönke , P. Schmelcher

Anisotropies of the cosmic microwave background (CMB) have proven to be a very powerful tool to constrain dark matter annihilation at the epoch of recombination. However, CMB constraints are currently derived using a number of reasonable…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Silvia Galli , Tracy R. Slatyer , Marcos Valdes , Fabio Iocco

Primordial Magnetic Fields (PMFs), long studied as relics of the early Universe, accelerate recombination and have been proposed as a way to relieve the Hubble tension. However, previous studies relied on simplified toy models. Here we use…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-17 Karsten Jedamzik , Levon Pogosian , Tom Abel

The recent implementation of radiative transfer algorithms in numerous hydrodynamics codes has led to a dramatic improvement in studies of feedback in various astrophysical environments. However, because of methodological limitations and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jordan Mirocha , Stephen Skory , Jack O. Burns , John H. Wise

It is believed that the first star-forming galaxies are the main drivers of cosmic reionization. It is usually assumed that there is a one-to-one relationship between the star formation rate (SFR) inside a galaxy and the host halo mass in…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-26 Chandra Shekhar Murmu , Kanan K. Datta , Suman Majumdar , Thomas R. Greve

We present a new hybrid code for large volume, high resolution simulations of cosmic reionization, which utilizes a N-body algorithm for dark matter, physically motivated prescriptions for baryons and star formation, and an adaptive ray…

Astrophysics · Physics 2009-11-11 Hy Trac , Renyue Cen

We show that the process of photoionizing a gas of atomic hydrogen and helium by line radiation whose energy is slightly above the helium single-ionization threshold is unstable if the helium fraction by number is less than approximately…

Astrophysics · Physics 2009-10-28 Ethan Bradford , Craig Hogan

We investigate the effect of helium on hydrogen reionisation using a hydrodynamical simulation combined with the cosmological radiative transfer code CRASH. The simulations are run in a 35.12/h comoving Mpc box using a variety of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 B. Ciardi , J. S. Bolton , A. Maselli , L. Graziani

When modelling the ionisation of gas in the intergalactic medium after reionisation, it is standard practice to assume a uniform radiation background. This assumption is not always appropriate; models with radiative transfer show that…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-02 Teresita Suarez , Andrew Pontzen

We calculate electron-hole generation and recombination rates for Coulomb scattering (Auger recombination and impact ionization) in Graphene. The conduction and valence band dispersion relation in Graphene together with energy and momentum…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Farhan Rana

The discoveries of a number of binary black hole mergers by LIGO and VIRGO has reinvigorated the interest that primordial black holes (PBHs) of tens of solar masses could contribute non-negligibly to the dark matter energy density. Should…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 Olga Mena , Sergio Palomares-Ruiz , Pablo Villanueva-Domingo , Samuel J. Witte

The reionization of helium describes the transition from its singly ionized state to a doubly-ionized state in the intergalactic medium (IGM). This process is important for the thermal evolution of the IGM and influences the mean free path…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Bidisha Bandyopadhyay , Dominik R. G. Schleicher

Post-selecting output states in measurements can effectively amplify weak signals and improve precision. However, post-selection effects may also introduce unintended biases in precision measurements. Here, we investigate the influence of…

Atomic Physics · Physics 2024-11-18 Jin-Lu Wen , Jia-Dong Tang , Ya-Nan Lv , Yu R. Sun , Chang-Ling Zou , Jun-Feng Dong , Shui-Ming Hu

We discuss resonance recombination for quarks and show that it is compatible with quark and hadron distributions in local thermal equilibrium. We then calculate realistic heavy quark phase space distributions in heavy ion collisions using…

Nuclear Theory · Physics 2015-05-30 Rainer J. Fries , Min He , Ralf Rapp

The energy budget in common-envelope events (CEEs) is not well understood, with substantial uncertainty even over to what extent the recombination energy stored in ionised hydrogen and helium might be used to help envelope ejection. We…

Solar and Stellar Astrophysics · Physics 2015-06-22 N. Ivanova , S. Justham , Ph. Podsiadlowski

Primordial chemistry began, at the recombination epoch, when the adiabatic expansion caused the temperature of the radiation to fall below 4000K. The chemistry of the early Universe involves the elements hydrogen, its isotope deuterium,…

Astrophysics · Physics 2009-10-31 Denis Puy
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