Discovery of hard X-rays from a cluster of protostars

Katsuji Koyama, Kenji Hamaguchi, Shiro Ueno, Naoto Kobayashi, Eric D. Feigelson

Research output: Contribution to journalArticle

110 Citations (Scopus)

Abstract

We report on the detection of hard X-rays from protostar candidates (Class I sources) in the R Coronae Australia (R CrA) molecular cloud. The hard X-rays are found even in the quiescent states with extremely high temperature of about 6 keV. One of the sources, probably the embedded far-infrared source R1, exhibited a powerful X-ray flare. These phenomena are similar to, but with a significantly higher temperature than, those seen in T Tauri stars. The flare spectrum is unusual, showing a broadened or double emission-line structure between 6.2 and 6.8 keV. Since X-rays are unexpected from current protostellar theory, these ASCA observations should have a significant impact on our understanding of star formation and the earliest phases of stellar evolution.

Original languageEnglish (US)
Pages (from-to)L87-L92
JournalPublications of the Astronomical Society of Japan
Volume48
Issue number5
DOIs
StatePublished - Jan 1 1996

Fingerprint

protostars
flares
x rays
T Tauri stars
stellar evolution
molecular clouds
coronas
corona
star formation

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Koyama, Katsuji ; Hamaguchi, Kenji ; Ueno, Shiro ; Kobayashi, Naoto ; Feigelson, Eric D. / Discovery of hard X-rays from a cluster of protostars. In: Publications of the Astronomical Society of Japan. 1996 ; Vol. 48, No. 5. pp. L87-L92.
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Discovery of hard X-rays from a cluster of protostars. / Koyama, Katsuji; Hamaguchi, Kenji; Ueno, Shiro; Kobayashi, Naoto; Feigelson, Eric D.

In: Publications of the Astronomical Society of Japan, Vol. 48, No. 5, 01.01.1996, p. L87-L92.

Research output: Contribution to journalArticle

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