Abstract
We report on the discovery of 10 additional galaxy clusters detected in the ongoing Swift/Burst Alert Telescope (BAT) all-sky survey. Among the newly BAT-discovered clusters there are Bullet, A85, Norma, and PKS 0745-19. Norma is the only cluster, among those presented here, which is resolved by BAT. For all the clusters, we perform a detailed spectral analysis using XMM-Newton and Swift/BAT data to investigate the presence of a hard (non-thermal) X-ray excess.We find that in most cases the clusters' emission in the 0.3-200 keV band can be explained by a multitemperature thermal model confirming our previous results. For two clusters (Bullet and A3667), we find evidence for the presence of a hard X-ray excess. In the case of the Bullet cluster, our analysis confirms the presence of a non-thermal, power-law-like, component with a 20-100 keV flux of 3.4×10-12 erg cm-2 s-1 as detected in previous studies. For A3667, the excess emission can be successfully modeled as a hot component (kT ∼ 13 keV). We thus conclude that the hard X-ray emission from galaxy clusters (except the Bullet) has most likely a thermal origin.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1688-1706 |
| Number of pages | 19 |
| Journal | Astrophysical Journal |
| Volume | 725 |
| Issue number | 2 |
| DOIs | |
| State | Published - Dec 20 2010 |
| Externally published | Yes |
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Keywords
- Acceleration of particles
- Galaxies: clusters: general
- Magnetic fields
- Radiation mechanisms: non-thermal
- X-rays: general
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science
Cite this
Galaxy clusters in the Swift/BAT era. II. 10 more clusters detected above 15 keV. / Ajello, M.; Rebusco, P.; Cappelluti, Nico; Reimer, O.; Böhringer, H.; Parola, V. La; Cusumano, G.
In: Astrophysical Journal, Vol. 725, No. 2, 20.12.2010, p. 1688-1706.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Galaxy clusters in the Swift/BAT era. II. 10 more clusters detected above 15 keV
AU - Ajello, M.
AU - Rebusco, P.
AU - Cappelluti, Nico
AU - Reimer, O.
AU - Böhringer, H.
AU - Parola, V. La
AU - Cusumano, G.
PY - 2010/12/20
Y1 - 2010/12/20
N2 - We report on the discovery of 10 additional galaxy clusters detected in the ongoing Swift/Burst Alert Telescope (BAT) all-sky survey. Among the newly BAT-discovered clusters there are Bullet, A85, Norma, and PKS 0745-19. Norma is the only cluster, among those presented here, which is resolved by BAT. For all the clusters, we perform a detailed spectral analysis using XMM-Newton and Swift/BAT data to investigate the presence of a hard (non-thermal) X-ray excess.We find that in most cases the clusters' emission in the 0.3-200 keV band can be explained by a multitemperature thermal model confirming our previous results. For two clusters (Bullet and A3667), we find evidence for the presence of a hard X-ray excess. In the case of the Bullet cluster, our analysis confirms the presence of a non-thermal, power-law-like, component with a 20-100 keV flux of 3.4×10-12 erg cm-2 s-1 as detected in previous studies. For A3667, the excess emission can be successfully modeled as a hot component (kT ∼ 13 keV). We thus conclude that the hard X-ray emission from galaxy clusters (except the Bullet) has most likely a thermal origin.
AB - We report on the discovery of 10 additional galaxy clusters detected in the ongoing Swift/Burst Alert Telescope (BAT) all-sky survey. Among the newly BAT-discovered clusters there are Bullet, A85, Norma, and PKS 0745-19. Norma is the only cluster, among those presented here, which is resolved by BAT. For all the clusters, we perform a detailed spectral analysis using XMM-Newton and Swift/BAT data to investigate the presence of a hard (non-thermal) X-ray excess.We find that in most cases the clusters' emission in the 0.3-200 keV band can be explained by a multitemperature thermal model confirming our previous results. For two clusters (Bullet and A3667), we find evidence for the presence of a hard X-ray excess. In the case of the Bullet cluster, our analysis confirms the presence of a non-thermal, power-law-like, component with a 20-100 keV flux of 3.4×10-12 erg cm-2 s-1 as detected in previous studies. For A3667, the excess emission can be successfully modeled as a hot component (kT ∼ 13 keV). We thus conclude that the hard X-ray emission from galaxy clusters (except the Bullet) has most likely a thermal origin.
KW - Acceleration of particles
KW - Galaxies: clusters: general
KW - Magnetic fields
KW - Radiation mechanisms: non-thermal
KW - X-rays: general
UR - http://www.scopus.com/inward/record.url?scp=78650084939&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=78650084939&partnerID=8YFLogxK
U2 - 10.1088/0004-637X/725/2/1688
DO - 10.1088/0004-637X/725/2/1688
M3 - Article
AN - SCOPUS:78650084939
VL - 725
SP - 1688
EP - 1706
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 2
ER -