Lyman-alpha radiation hydrodynamics of galactic winds before cosmic
reionization
A. Smith, V. Bromm, and A. Loeb. (2016)cite arxiv:1607.07166Comment: 14 pages, 11 figures, submitted to MNRAS.
Abstract
The dynamical impact of Lyman-alpha (Ly\alpha) radiation pressure on galaxy
formation depends on the rate and duration of momentum transfer between
Ly\alpha photons and neutral hydrogen gas. Although photon trapping has the
potential to multiply the effective force, ionizing radiation from stellar
sources may relieve the Ly\alpha pressure before appreciably affecting the
kinematics of the host galaxy or efficiently coupling Ly\alpha photons to the
outflow. We present self-consistent Ly\alpha radiation-hydrodynamics
simulations of high-$z$ galaxy environments by coupling the Cosmic Ly\alpha
Transfer code (COLT) with spherically symmetric Lagrangian frame hydrodynamics.
The accurate but computationally expensive Monte-Carlo radiative transfer
calculations are feasible under the one-dimensional approximation. In certain
cases Ly\alpha feedback significantly enhances the velocity of the shell of
gas expanding around a central source. Radiative feedback alone is capable of
ejecting baryons into the intergalactic medium (IGM) for protogalaxies with a
virial mass of $M_vir 10^8~M_ødot$. We compare the
Ly\alpha signatures of Population III stars with $10^5$ K blackbody emission
to that of direct collapse black holes with a nonthermal Compton-thick spectrum
and find substantial differences. For both sources, the flux emerging from the
galaxy is reprocessed by the IGM such that the observed Ly\alpha luminosity
is reduced significantly and the time-averaged velocity offset of the
Ly\alpha peak is shifted redward.
Description
[1607.07166] Lyman-alpha radiation hydrodynamics of galactic winds before cosmic reionization
%0 Generic
%1 smith2016lymanalpha
%A Smith, Aaron
%A Bromm, Volker
%A Loeb, Abraham
%D 2016
%K hydrodynamics lya radiation
%T Lyman-alpha radiation hydrodynamics of galactic winds before cosmic
reionization
%U http://arxiv.org/abs/1607.07166
%X The dynamical impact of Lyman-alpha (Ly\alpha) radiation pressure on galaxy
formation depends on the rate and duration of momentum transfer between
Ly\alpha photons and neutral hydrogen gas. Although photon trapping has the
potential to multiply the effective force, ionizing radiation from stellar
sources may relieve the Ly\alpha pressure before appreciably affecting the
kinematics of the host galaxy or efficiently coupling Ly\alpha photons to the
outflow. We present self-consistent Ly\alpha radiation-hydrodynamics
simulations of high-$z$ galaxy environments by coupling the Cosmic Ly\alpha
Transfer code (COLT) with spherically symmetric Lagrangian frame hydrodynamics.
The accurate but computationally expensive Monte-Carlo radiative transfer
calculations are feasible under the one-dimensional approximation. In certain
cases Ly\alpha feedback significantly enhances the velocity of the shell of
gas expanding around a central source. Radiative feedback alone is capable of
ejecting baryons into the intergalactic medium (IGM) for protogalaxies with a
virial mass of $M_vir 10^8~M_ødot$. We compare the
Ly\alpha signatures of Population III stars with $10^5$ K blackbody emission
to that of direct collapse black holes with a nonthermal Compton-thick spectrum
and find substantial differences. For both sources, the flux emerging from the
galaxy is reprocessed by the IGM such that the observed Ly\alpha luminosity
is reduced significantly and the time-averaged velocity offset of the
Ly\alpha peak is shifted redward.
@misc{smith2016lymanalpha,
abstract = {The dynamical impact of Lyman-alpha (Ly{\alpha}) radiation pressure on galaxy
formation depends on the rate and duration of momentum transfer between
Ly{\alpha} photons and neutral hydrogen gas. Although photon trapping has the
potential to multiply the effective force, ionizing radiation from stellar
sources may relieve the Ly{\alpha} pressure before appreciably affecting the
kinematics of the host galaxy or efficiently coupling Ly{\alpha} photons to the
outflow. We present self-consistent Ly{\alpha} radiation-hydrodynamics
simulations of high-$z$ galaxy environments by coupling the Cosmic Ly{\alpha}
Transfer code (COLT) with spherically symmetric Lagrangian frame hydrodynamics.
The accurate but computationally expensive Monte-Carlo radiative transfer
calculations are feasible under the one-dimensional approximation. In certain
cases Ly{\alpha} feedback significantly enhances the velocity of the shell of
gas expanding around a central source. Radiative feedback alone is capable of
ejecting baryons into the intergalactic medium (IGM) for protogalaxies with a
virial mass of $M_{\rm vir} \lesssim 10^8~{\rm M}_\odot$. We compare the
Ly{\alpha} signatures of Population III stars with $10^5$ K blackbody emission
to that of direct collapse black holes with a nonthermal Compton-thick spectrum
and find substantial differences. For both sources, the flux emerging from the
galaxy is reprocessed by the IGM such that the observed Ly{\alpha} luminosity
is reduced significantly and the time-averaged velocity offset of the
Ly{\alpha} peak is shifted redward.},
added-at = {2016-07-26T10:05:14.000+0200},
author = {Smith, Aaron and Bromm, Volker and Loeb, Abraham},
biburl = {https://www.bibsonomy.org/bibtex/29478c125d07b89f63e95d8940611839e/miki},
description = {[1607.07166] Lyman-alpha radiation hydrodynamics of galactic winds before cosmic reionization},
interhash = {c346fa465c58491c55869ce82576b1ec},
intrahash = {9478c125d07b89f63e95d8940611839e},
keywords = {hydrodynamics lya radiation},
note = {cite arxiv:1607.07166Comment: 14 pages, 11 figures, submitted to MNRAS},
timestamp = {2016-07-26T10:05:14.000+0200},
title = {Lyman-alpha radiation hydrodynamics of galactic winds before cosmic
reionization},
url = {http://arxiv.org/abs/1607.07166},
year = 2016
}