Astronomy and Astrophysics – Astronomy
Scientific paper
Dec 2000
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000aas...19711405t&link_type=abstract
American Astronomical Society, 197th AAS Meeting, #114.05; Bulletin of the American Astronomical Society, Vol. 32, p.1597
Astronomy and Astrophysics
Astronomy
Scientific paper
A young stellar object (YSO) evolves from a molecular cloud core through the protostellar and T Tauri phases to a main sequence star. In order to search when a star begins to emit X-rays, we observed ρ Oph molecular cloud (d ~160 pc) and Orion Molecular Cloud (OMC) 2/3 regions (d ~450 pc) with ACIS-I instrument onboard Chandra X-ray Observatory (CXO). Using hard X-ray band (> 2 keV) of CXO with up to sub-arcsec resolution, we detected more than 70 % of the 22 Class I protostars, in a 17' x 17' field of view at the ρ Oph molecular cloud. The high detection rate of Class I protostars in this Chandra observation changed our understanding qualitatively: Most Class I protostars have emitted prominent X-rays already. Seven of the detected Class I protostars showed nine X-ray flares during the 100 ksec observation time. This indicates that Class I protostars are magnetically very active. In the OMC-2/3 regions, we further discovered very hard X-rays (> 3 keV) from two sources which is most likely Class 0 protostars, earlier phase of protostars. The X-ray spectra of these sources show absorption column of as much as (1--3) x1023 H cm-2. This result indicates for the first time that protostars can emit X-rays preceding Class I phase certainly.
Bally John
Hamaguchi Kenji
Imanishi Kensuke
Koyama Katsuji
Reipurth Bo
No associations
LandOfFree
Chandra/ACIS Observations of Protostars 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/ACIS Observations of Protostars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chandra/ACIS Observations of Protostars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1728384