TY - JOUR
T1 - A high-velocity transient outflow in ηcarinae
AU - Behar, Ehud
AU - Nordon, Raanan
AU - Soker, Noam
N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2007
Y1 - 2007
N2 - We analyze velocity profiles of the X-ray spectral lines emitted by the η Carinae (η Car) stellar binary at four epochs, just before the X-ray minimum (associated with periastron) and more than 2 years before the minimum (∼apastron). The profiles are nicely resolved by the HETGS spectrometer on board Chandra. Far from periastron, we find symmetrical lines that are more or less centered at zero velocity. Closer to periastron, the lines broaden, shift toward the blue, and become visibly asymmetric. While the quiescent X-ray emission and slight (<200 km s-1) centroid shifts can be ascribed to the ordinary continuous binary wind interaction and to the orbital velocity of the secondary star, the observed high-velocity emission up to ∼2000 km s-1 and the abrupt flares during which it occurs cannot. This leads us to interpret the high-velocity flaring emission as due to a fast collimated outflow of ionized gas.
AB - We analyze velocity profiles of the X-ray spectral lines emitted by the η Carinae (η Car) stellar binary at four epochs, just before the X-ray minimum (associated with periastron) and more than 2 years before the minimum (∼apastron). The profiles are nicely resolved by the HETGS spectrometer on board Chandra. Far from periastron, we find symmetrical lines that are more or less centered at zero velocity. Closer to periastron, the lines broaden, shift toward the blue, and become visibly asymmetric. While the quiescent X-ray emission and slight (<200 km s-1) centroid shifts can be ascribed to the ordinary continuous binary wind interaction and to the orbital velocity of the secondary star, the observed high-velocity emission up to ∼2000 km s-1 and the abrupt flares during which it occurs cannot. This leads us to interpret the high-velocity flaring emission as due to a fast collimated outflow of ionized gas.
KW - Stars: Individual (h Carinae)
KW - Stars: mass loss
KW - Techniques: Spectroscopic
KW - X-rays: Stars Online material: Color figures
UR - http://www.scopus.com/inward/record.url?scp=44649086276&partnerID=8YFLogxK
U2 - 10.1086/521787
DO - 10.1086/521787
M3 - 文章
AN - SCOPUS:44649086276
VL - 666
SP - L97-L100
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 2 PART 2
ER -