TY - JOUR
T1 - Discovery of hot gas in outflow in NGC 3379
AU - Trinchieri, G.
AU - Pellegrini, S.
AU - Fabbiano, G.
AU - Fu, R.
AU - Brassington, N. J.
AU - Zezas, A.
AU - Kim, D. W.
AU - Gallagher, J.
AU - Angelini, L.
AU - Davies, R. L.
AU - Kalogera, V.
AU - King, A. R.
AU - Zepf, S.
PY - 2008/12/1
Y1 - 2008/12/1
N2 - We report the discovery of a faint (Lx ∼ 4 ± 1.5 × 1037 ergs s-1, 0.5-2 keV), outflowing gaseous hot interstellar medium (ISM) in NGC 3379. This represents the lowest X-ray luminosity ever measured from a hot phase of the ISM in a nearby early-type galaxy. The discovery of the hot ISM in a very deep Chandra observation was possible thanks to its unique spectral and spatial signatures, which distinguish it from the integrated stellar X-ray emission, responsible for most of the unresolved emission in the Chandra data. This hot component is found in a region of ∼800 pc in radius at the center of the galaxy and has a total mass M ∼ 3 ± 1 × 105 M⊙. Independent theoretical prediction of the characteristics of an ISM in this galaxy, based on the intrinsic properties of NGC 3379, reproduce well the observed luminosity, temperature, and radial distribution and mass of the hot gas, and indicate that the gas is in an outflowing phase, predicted by models but not observed in any system so far.
AB - We report the discovery of a faint (Lx ∼ 4 ± 1.5 × 1037 ergs s-1, 0.5-2 keV), outflowing gaseous hot interstellar medium (ISM) in NGC 3379. This represents the lowest X-ray luminosity ever measured from a hot phase of the ISM in a nearby early-type galaxy. The discovery of the hot ISM in a very deep Chandra observation was possible thanks to its unique spectral and spatial signatures, which distinguish it from the integrated stellar X-ray emission, responsible for most of the unresolved emission in the Chandra data. This hot component is found in a region of ∼800 pc in radius at the center of the galaxy and has a total mass M ∼ 3 ± 1 × 105 M⊙. Independent theoretical prediction of the characteristics of an ISM in this galaxy, based on the intrinsic properties of NGC 3379, reproduce well the observed luminosity, temperature, and radial distribution and mass of the hot gas, and indicate that the gas is in an outflowing phase, predicted by models but not observed in any system so far.
KW - Galaxies: elliptical and lenticular, cD
KW - Galaxies: individual (NGC 3379)
KW - X-rays: ISM
KW - X-rays: galaxies
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U2 - 10.1086/592287
DO - 10.1086/592287
M3 - Article
AN - SCOPUS:56849120295
VL - 688
SP - 1000
EP - 1008
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 2
ER -