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Title: On the capture of dark matter by neutron stars

Abstract

We calculate the number of dark matter particles that a neutron star accumulates over its lifetime as it rotates around the center of a galaxy, when the dark matter particle is a self-interacting boson but does not self-annihilate. We take into account dark matter interactions with baryonic matter and the time evolution of the dark matter sphere as it collapses within the neutron star. We show that dark matter self-interactions play an important role in the rapid accumulation of dark matter in the core of the neutron star. We consider the possibility of determining an exclusion region of the parameter space for dark matter mass and dark matter interaction cross section with the nucleons as well as dark matter self-interaction cross section, based on the observation of old neutron stars. We show that for a dark matter density of 10{sup 3} GeV/cm{sup 3}and dark matter mass m{sub χ} ∼< 10 GeV, there is a potential exclusion region for dark matter interactions with nucleons that is three orders of magnitude more stringent than without self-interactions. The potential exclusion region for dark matter self-interaction cross sections is many orders of magnitude stronger than the current Bullet Cluster limit. For example, for highmore » dark matter density regions, we find that for m{sub χ} ∼ 10 GeV when the dark matter interaction cross section with the nucleons ranges from σ{sub χn} ∼ 10{sup −52} cm{sup 2} to σ{sub χn} ∼ 10{sup −57} cm{sup 2}, the dark matter self-interaction cross section limit is σ{sub χχ} ∼< 10{sup −33} cm{sup 2}, which is about ten orders of magnitude stronger than the Bullet Cluster limit.« less

Authors:
 [1]; ;  [2];  [3]
  1. Department of Astronomy and Space Sciences, Faculty of Sciences, Istanbul University, University, Beyazit, Istanbul, 34119 Turkey (Turkey)
  2. Department of Physics, University of Arizona, 1118 East 4th Street, Tucson, AZ, 85721 (United States)
  3. Department of Physics and Astronomy, University of Iowa, 203 Van Allen Hall, Iowa City, IA, 52242 (United States)
Publication Date:
OSTI Identifier:
22373599
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CROSS SECTIONS; GALAXIES; GEV RANGE 01-10; INTERACTING BOSON MODEL; LIFETIME; NEUTRON STARS; NONLUMINOUS MATTER; NUCLEONS

Citation Formats

Güver, Tolga, Erkoca, Arif Emre, Sarcevic, Ina, and Reno, Mary Hall, E-mail: tolga.guver@istanbul.edu.tr, E-mail: aeerkoca@gmail.com, E-mail: mary-hall-reno@uiowa.edu, E-mail: ina@physics.arizona.edu. On the capture of dark matter by neutron stars. United States: N. p., 2014. Web. doi:10.1088/1475-7516/2014/05/013.
Güver, Tolga, Erkoca, Arif Emre, Sarcevic, Ina, & Reno, Mary Hall, E-mail: tolga.guver@istanbul.edu.tr, E-mail: aeerkoca@gmail.com, E-mail: mary-hall-reno@uiowa.edu, E-mail: ina@physics.arizona.edu. On the capture of dark matter by neutron stars. United States. doi:10.1088/1475-7516/2014/05/013.
Güver, Tolga, Erkoca, Arif Emre, Sarcevic, Ina, and Reno, Mary Hall, E-mail: tolga.guver@istanbul.edu.tr, E-mail: aeerkoca@gmail.com, E-mail: mary-hall-reno@uiowa.edu, E-mail: ina@physics.arizona.edu. Thu . "On the capture of dark matter by neutron stars". United States. doi:10.1088/1475-7516/2014/05/013.
@article{osti_22373599,
title = {On the capture of dark matter by neutron stars},
author = {Güver, Tolga and Erkoca, Arif Emre and Sarcevic, Ina and Reno, Mary Hall, E-mail: tolga.guver@istanbul.edu.tr, E-mail: aeerkoca@gmail.com, E-mail: mary-hall-reno@uiowa.edu, E-mail: ina@physics.arizona.edu},
abstractNote = {We calculate the number of dark matter particles that a neutron star accumulates over its lifetime as it rotates around the center of a galaxy, when the dark matter particle is a self-interacting boson but does not self-annihilate. We take into account dark matter interactions with baryonic matter and the time evolution of the dark matter sphere as it collapses within the neutron star. We show that dark matter self-interactions play an important role in the rapid accumulation of dark matter in the core of the neutron star. We consider the possibility of determining an exclusion region of the parameter space for dark matter mass and dark matter interaction cross section with the nucleons as well as dark matter self-interaction cross section, based on the observation of old neutron stars. We show that for a dark matter density of 10{sup 3} GeV/cm{sup 3}and dark matter mass m{sub χ} ∼< 10 GeV, there is a potential exclusion region for dark matter interactions with nucleons that is three orders of magnitude more stringent than without self-interactions. The potential exclusion region for dark matter self-interaction cross sections is many orders of magnitude stronger than the current Bullet Cluster limit. For example, for high dark matter density regions, we find that for m{sub χ} ∼ 10 GeV when the dark matter interaction cross section with the nucleons ranges from σ{sub χn} ∼ 10{sup −52} cm{sup 2} to σ{sub χn} ∼ 10{sup −57} cm{sup 2}, the dark matter self-interaction cross section limit is σ{sub χχ} ∼< 10{sup −33} cm{sup 2}, which is about ten orders of magnitude stronger than the Bullet Cluster limit.},
doi = {10.1088/1475-7516/2014/05/013},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2014,
place = {United States},
year = {Thu May 01 00:00:00 EDT 2014},
month = {Thu May 01 00:00:00 EDT 2014}
}
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