On dark peaks and missing mass: A weak-lensing mass reconstruction of the merging cluster system A520

Douglas Clowe, Maxim Markevitch, Maruša Bradač, Anthony H. Gonzalez, Sun Mi Chung, Richard Massey, Dennis F Zaritsky

Research output: Contribution to journalArticle

51 Citations (Scopus)

Abstract

Merging clusters of galaxies are unique in their power to directly probe and place limits on the self-interaction cross-section of dark matter. Detailed observations of several merging clusters have shown the intracluster gas to be displaced from the centroids of dark matter and galaxy density by ram pressure, while the latter components are spatially coincident, consistent with collisionless dark matter. This has been used to place upper limits on the dark matter particle self-interaction cross-section of order 1cm2 g -1. The cluster A520 has been seen as a possible exception. We revisit A520 presenting new Hubble Space Telescope Advanced Camera for Surveys mosaic images and a Magellan image set. We perform a detailed weak-lensing analysis and show that the weak-lensing mass measurements and morphologies of the core galaxy-filled structures are mostly in good agreement with previous works. There is, however, one significant difference: We do not detect the previously claimed "dark core" that contains excess mass with no significant galaxy overdensity at the location of the X-ray plasma. This peak has been suggested to be indicative of a large self-interaction cross-section for dark matter (at least 5σ larger than the upper limit of 0.7 cm 2 g-1 determined by observations of the Bullet Cluster). We find no such indication and instead find that the mass distribution of A520, after subtraction of the X-ray plasma mass, is in good agreement with the luminosity distribution of the cluster galaxies. We conclude that A520 shows no evidence to contradict the collisionless dark matter scenario.

Original languageEnglish (US)
Article number128
JournalAstrophysical Journal
Volume758
Issue number2
DOIs
StatePublished - Oct 20 2012

Fingerprint

dark matter
galaxies
cross section
cross sections
ram
plasma
interactions
mass distribution
Hubble Space Telescope
subtraction
centroids
indication
x rays
cameras
luminosity
probe
probes
gases
gas

Keywords

  • dark matter
  • galaxies: clusters: individual (A520)
  • gravitational lensing: weak

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

On dark peaks and missing mass : A weak-lensing mass reconstruction of the merging cluster system A520. / Clowe, Douglas; Markevitch, Maxim; Bradač, Maruša; Gonzalez, Anthony H.; Chung, Sun Mi; Massey, Richard; Zaritsky, Dennis F.

In: Astrophysical Journal, Vol. 758, No. 2, 128, 20.10.2012.

Research output: Contribution to journalArticle

Clowe, Douglas ; Markevitch, Maxim ; Bradač, Maruša ; Gonzalez, Anthony H. ; Chung, Sun Mi ; Massey, Richard ; Zaritsky, Dennis F. / On dark peaks and missing mass : A weak-lensing mass reconstruction of the merging cluster system A520. In: Astrophysical Journal. 2012 ; Vol. 758, No. 2.
@article{a3657b22012b43bb903a7ce2560955bc,
title = "On dark peaks and missing mass: A weak-lensing mass reconstruction of the merging cluster system A520",
abstract = "Merging clusters of galaxies are unique in their power to directly probe and place limits on the self-interaction cross-section of dark matter. Detailed observations of several merging clusters have shown the intracluster gas to be displaced from the centroids of dark matter and galaxy density by ram pressure, while the latter components are spatially coincident, consistent with collisionless dark matter. This has been used to place upper limits on the dark matter particle self-interaction cross-section of order 1cm2 g -1. The cluster A520 has been seen as a possible exception. We revisit A520 presenting new Hubble Space Telescope Advanced Camera for Surveys mosaic images and a Magellan image set. We perform a detailed weak-lensing analysis and show that the weak-lensing mass measurements and morphologies of the core galaxy-filled structures are mostly in good agreement with previous works. There is, however, one significant difference: We do not detect the previously claimed {"}dark core{"} that contains excess mass with no significant galaxy overdensity at the location of the X-ray plasma. This peak has been suggested to be indicative of a large self-interaction cross-section for dark matter (at least 5σ larger than the upper limit of 0.7 cm 2 g-1 determined by observations of the Bullet Cluster). We find no such indication and instead find that the mass distribution of A520, after subtraction of the X-ray plasma mass, is in good agreement with the luminosity distribution of the cluster galaxies. We conclude that A520 shows no evidence to contradict the collisionless dark matter scenario.",
keywords = "dark matter, galaxies: clusters: individual (A520), gravitational lensing: weak",
author = "Douglas Clowe and Maxim Markevitch and Maruša Bradač and Gonzalez, {Anthony H.} and Chung, {Sun Mi} and Richard Massey and Zaritsky, {Dennis F}",
year = "2012",
month = "10",
day = "20",
doi = "10.1088/0004-637X/758/2/128",
language = "English (US)",
volume = "758",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2",

}

TY - JOUR

T1 - On dark peaks and missing mass

T2 - A weak-lensing mass reconstruction of the merging cluster system A520

AU - Clowe, Douglas

AU - Markevitch, Maxim

AU - Bradač, Maruša

AU - Gonzalez, Anthony H.

AU - Chung, Sun Mi

AU - Massey, Richard

AU - Zaritsky, Dennis F

PY - 2012/10/20

Y1 - 2012/10/20

N2 - Merging clusters of galaxies are unique in their power to directly probe and place limits on the self-interaction cross-section of dark matter. Detailed observations of several merging clusters have shown the intracluster gas to be displaced from the centroids of dark matter and galaxy density by ram pressure, while the latter components are spatially coincident, consistent with collisionless dark matter. This has been used to place upper limits on the dark matter particle self-interaction cross-section of order 1cm2 g -1. The cluster A520 has been seen as a possible exception. We revisit A520 presenting new Hubble Space Telescope Advanced Camera for Surveys mosaic images and a Magellan image set. We perform a detailed weak-lensing analysis and show that the weak-lensing mass measurements and morphologies of the core galaxy-filled structures are mostly in good agreement with previous works. There is, however, one significant difference: We do not detect the previously claimed "dark core" that contains excess mass with no significant galaxy overdensity at the location of the X-ray plasma. This peak has been suggested to be indicative of a large self-interaction cross-section for dark matter (at least 5σ larger than the upper limit of 0.7 cm 2 g-1 determined by observations of the Bullet Cluster). We find no such indication and instead find that the mass distribution of A520, after subtraction of the X-ray plasma mass, is in good agreement with the luminosity distribution of the cluster galaxies. We conclude that A520 shows no evidence to contradict the collisionless dark matter scenario.

AB - Merging clusters of galaxies are unique in their power to directly probe and place limits on the self-interaction cross-section of dark matter. Detailed observations of several merging clusters have shown the intracluster gas to be displaced from the centroids of dark matter and galaxy density by ram pressure, while the latter components are spatially coincident, consistent with collisionless dark matter. This has been used to place upper limits on the dark matter particle self-interaction cross-section of order 1cm2 g -1. The cluster A520 has been seen as a possible exception. We revisit A520 presenting new Hubble Space Telescope Advanced Camera for Surveys mosaic images and a Magellan image set. We perform a detailed weak-lensing analysis and show that the weak-lensing mass measurements and morphologies of the core galaxy-filled structures are mostly in good agreement with previous works. There is, however, one significant difference: We do not detect the previously claimed "dark core" that contains excess mass with no significant galaxy overdensity at the location of the X-ray plasma. This peak has been suggested to be indicative of a large self-interaction cross-section for dark matter (at least 5σ larger than the upper limit of 0.7 cm 2 g-1 determined by observations of the Bullet Cluster). We find no such indication and instead find that the mass distribution of A520, after subtraction of the X-ray plasma mass, is in good agreement with the luminosity distribution of the cluster galaxies. We conclude that A520 shows no evidence to contradict the collisionless dark matter scenario.

KW - dark matter

KW - galaxies: clusters: individual (A520)

KW - gravitational lensing: weak

UR - http://www.scopus.com/inward/record.url?scp=84867361227&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84867361227&partnerID=8YFLogxK

U2 - 10.1088/0004-637X/758/2/128

DO - 10.1088/0004-637X/758/2/128

M3 - Article

AN - SCOPUS:84867361227

VL - 758

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 128

ER -