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Title: Dipole of the Epoch of reionization 21-cm signal

Abstract

The motion of the Solar System with respect to the cosmic rest frame modulates the monopole of the epoch of reionization 21-cm signal into a dipole. This dipole has a characteristic frequency dependence that is dominated by the frequency derivative of the monopole signal. We argue that although the signal is weaker by a factor of ~100, there are significant benefits in measuring the dipole. Most importantly, the direction of the cosmic velocity vector is known exquisitely well from the cosmic microwave background and is not aligned with the galaxy velocity vector that modulates the foreground monopole. Furthermore, an experiment designed to measure a dipole can rely on differencing patches of the sky rather than making an absolute signal measurement, which helps with some systematic effects.

Authors:
 [1]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1368677
Alternate Identifier(s):
OSTI ID: 1351053
Report Number(s):
BNL-114019-2017-JA
Journal ID: ISSN 0031-9007; PRLTAO; TRN: US1702753
Grant/Contract Number:
SC00112704; 16-038
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 118; Journal Issue: 15; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Slosar, Anze. Dipole of the Epoch of reionization 21-cm signal. United States: N. p., 2017. Web. doi:10.1103/PhysRevLett.118.151301.
Slosar, Anze. Dipole of the Epoch of reionization 21-cm signal. United States. doi:10.1103/PhysRevLett.118.151301.
Slosar, Anze. Mon . "Dipole of the Epoch of reionization 21-cm signal". United States. doi:10.1103/PhysRevLett.118.151301. https://www.osti.gov/servlets/purl/1368677.
@article{osti_1368677,
title = {Dipole of the Epoch of reionization 21-cm signal},
author = {Slosar, Anze},
abstractNote = {The motion of the Solar System with respect to the cosmic rest frame modulates the monopole of the epoch of reionization 21-cm signal into a dipole. This dipole has a characteristic frequency dependence that is dominated by the frequency derivative of the monopole signal. We argue that although the signal is weaker by a factor of ~100, there are significant benefits in measuring the dipole. Most importantly, the direction of the cosmic velocity vector is known exquisitely well from the cosmic microwave background and is not aligned with the galaxy velocity vector that modulates the foreground monopole. Furthermore, an experiment designed to measure a dipole can rely on differencing patches of the sky rather than making an absolute signal measurement, which helps with some systematic effects.},
doi = {10.1103/PhysRevLett.118.151301},
journal = {Physical Review Letters},
number = 15,
volume = 118,
place = {United States},
year = {Mon Apr 10 00:00:00 EDT 2017},
month = {Mon Apr 10 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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