Abstract
The amount of detected baryons in the local universe is at least a factor of 2 smaller than that measured at high redshift. It is believed that a significant fraction of the baryons in the current universe is "hiding" in a hot filamentary structure filling the intergalactic space, the warm-hot intergalactic medium (WHIM). We found evidence of the missing baryons in the WHIM by detecting their signature on the angular correlation of diffuse X-ray emission with the XMM-Newton satellite. Our result indicates that 12%± 5% of the total diffuse X-ray emission in the energy range 0.4-0.6 keV is due to intergalactic filaments. The statistical significance of our detection is several sigmas (χ2 > 136, N = 19). The error bar in the X-ray flux is dominated, instead, by cosmic variation and model uncertainties.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1127-1131 |
| Number of pages | 5 |
| Journal | Astrophysical Journal |
| Volume | 695 |
| Issue number | 2 |
| DOIs | |
| State | Published - Apr 20 2009 |
Fingerprint
Keywords
- Large-scale structure of universe
- X-rays: diffuse background
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science
Cite this
Evidence for the missing baryons in the angular correlation of the diffuse X-ray background. / Galeazzi, Massimiliano; Gupta, A.; Ursino, E.
In: Astrophysical Journal, Vol. 695, No. 2, 20.04.2009, p. 1127-1131.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Evidence for the missing baryons in the angular correlation of the diffuse X-ray background
AU - Galeazzi, Massimiliano
AU - Gupta, A.
AU - Ursino, E.
PY - 2009/4/20
Y1 - 2009/4/20
N2 - The amount of detected baryons in the local universe is at least a factor of 2 smaller than that measured at high redshift. It is believed that a significant fraction of the baryons in the current universe is "hiding" in a hot filamentary structure filling the intergalactic space, the warm-hot intergalactic medium (WHIM). We found evidence of the missing baryons in the WHIM by detecting their signature on the angular correlation of diffuse X-ray emission with the XMM-Newton satellite. Our result indicates that 12%± 5% of the total diffuse X-ray emission in the energy range 0.4-0.6 keV is due to intergalactic filaments. The statistical significance of our detection is several sigmas (χ2 > 136, N = 19). The error bar in the X-ray flux is dominated, instead, by cosmic variation and model uncertainties.
AB - The amount of detected baryons in the local universe is at least a factor of 2 smaller than that measured at high redshift. It is believed that a significant fraction of the baryons in the current universe is "hiding" in a hot filamentary structure filling the intergalactic space, the warm-hot intergalactic medium (WHIM). We found evidence of the missing baryons in the WHIM by detecting their signature on the angular correlation of diffuse X-ray emission with the XMM-Newton satellite. Our result indicates that 12%± 5% of the total diffuse X-ray emission in the energy range 0.4-0.6 keV is due to intergalactic filaments. The statistical significance of our detection is several sigmas (χ2 > 136, N = 19). The error bar in the X-ray flux is dominated, instead, by cosmic variation and model uncertainties.
KW - Large-scale structure of universe
KW - X-rays: diffuse background
UR - http://www.scopus.com/inward/record.url?scp=70449734184&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=70449734184&partnerID=8YFLogxK
U2 - 10.1088/0004-637X/695/2/1127
DO - 10.1088/0004-637X/695/2/1127
M3 - Article
AN - SCOPUS:70449734184
VL - 695
SP - 1127
EP - 1131
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 2
ER -