8th HEAD Meeting, 8-11 September, 2004
Session 24 Supernova Remnants and the Interstellar Medium
Poster, Friday, September 10, 2004, 9:00am-10:00pm

[Previous] | [Session 24] | [Next]


[24.12] A Chandra Observation of the Mysterious Bow-Shock Nebula G70.7+1.2

Z. Arzoumanian (USRA/NASA-GSFC), J. Cordes (Cornell Univ.), D. Van Buren (Caltech), M. Corcoran (USRA/NASA-GSFC), S. Safi-Harb (Univ. of Manitoba), R. Petre (NASA-GSFC)

The nature of the optical and radio nebula G70.7+1.2 has been a matter of uncertainty, and some debate, for more than 50 years. At various times, it has been described (among other things) as a supernova remnant, compact HII region, massive pre-main sequence star, interaction of a massive star's wind with a molecular cloud, and a Be-star/neutron-star binary. The last two possibilities remain viable; distinguishing between them or some as-yet-unidentified source model has motivated us to perform observations of G70.7 with the Chandra X-ray telescope. The high-resolution imaging spectroscopy data provided by the ACIS-S detector reveal extended soft X-ray emission closely tracing the FeII line-emitting regions visible in the infrared. A hard point-like X-ray source is also evident, centered on the radio and optical arcs that suggest a bow-shock structure, but unexpectedly offset by 3-4 arcsec from the luminous IR star thought to power G70.7's optical nebulosity. X-ray and IR images together with the spectral properties of the compact and extended X-ray emissions are presented here. We also discuss the implications of the Chandra observation for identification of the source model and astrophysical processes responsible for G70.7's unusual characteristics: a preliminary analysis suggests that interactions between a massive star's wind, the relativistic wind from a high-energy source such as a pulsar, and molecular material in an adjacent cloud together sculpt this unique environment.


[Previous] | [Session 24] | [Next]

Bulletin of the American Astronomical Society, 36 #3
© 2004. The American Astronomical Soceity.