Chandra Observations of Associates of $η$ Car: I. Luminosities

Details Chandra Observations of Associates of $η$ Car: I. Luminosities Chandra Observations of Associates of $η$ Car: I. Luminosities

2003-01-24

arxiv.org/abs/astro-ph/0301485v1

Astrophys.J. 589 (2003) 509-525

Astronomy and Astrophysics

Astrophysics

accepted by ApJ

Scientific paper

10.1086/374355

The region around the $\eta$ Car nebula has three OB associations, which contain a Wolf-Rayet star and several massive O3 stars. An early Chandra ACIS-I image was centered on $\eta$ Car and includes Trumpler 16 and part of Trumpler 14. The Chandra image confirms the well-known result that O and very early B stars are X-ray sources with L$_X$ $\simeq$ 10$^{-7} \times$ L$_{bol}$ over an X-ray luminosity range of about 100. Two new anomalously strong X-ray sources have been found among the hot star population, Tr 16-244, a heavily-reddened O3 I star, and Tr 16-22, a heavily-reddened O8.5 V star. Two stars have an unusually large L$_X$/L$_{bol}$: HD 93162, a Wolf-Rayet star (and possible binary), and Tr 16-22, a possible colliding wind binary In addition, a population of sources associated with cool stars is detected. In the color-magnitude diagram, these X-ray sources sit above the sequence of field stars in the Carina arm. The OB stars are on average more X-ray luminous than the cool star X-ray sources. X-ray sources among A stars have similar X-ray luminosities to cooler stars, and may be due to cooler companions. Upper limits are presented for B stars which are not detected in X-rays. These upper limits are also the upper limits for any cool companions which the hot stars may have. Hardness ratios are presented for the most luminous sources in bands 0.5 to 0.9 keV, 0.9 to 1.5 keV, and 1.5 to 2.04 kev. The available information on the binary nature of the hot stars is discussed, but binarity does not correlate with X-ray strength in a simple way.

Affiliated with

Also associated with

No associations

Rating

Chandra Observations of Associates of $η$ Car: I. Luminosities does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Chandra Observations of Associates of $η$ Car: I. Luminosities, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chandra Observations of Associates of $η$ Car: I. Luminosities will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-709405