[ITAL]HUBBLE SPACE TELESCOPE[/ITAL][ITAL]Hubble Space Telescope[/ITAL] Wide Field Planetary Camera 2 Imaging of Shocks in Superbubbles
Open Access
- 1 March 2000
- journal article
- research article
- Published by American Astronomical Society in The Astronomical Journal
- Vol. 119 (3) , 1317-1324
- https://doi.org/10.1086/301278
Abstract
Bright X-ray emission has been detected in superbubbles in the Large Magellanic Cloud (LMC), and it is suggested that supernova remnants (SNRs) near the inner-shell walls are responsible for this X-ray emission. To identify SNR shocks in superbubble interiors, we have obtained Hubble Space Telescope Wide Field Planetary Camera 2 emission-line images of the X-ray–bright superbubbles DEM L152 and DEM L192 and the X-ray–dim superbubble DEM L106. We use these images to examine the shell morphology and [S II]/Hα ratio variations in detail. Of these three superbubbles, DEM L152 has the highest X-ray surface brightness, the most filamentary nebular morphology, the largest expansion velocity (~40 km s-1), and the highest [S II]/Hα ratio (0.4–0.6). Its [S II]/Hα ratio increases outward and peaks in sharp filaments along the periphery. DEM L192 has a moderate X-ray surface brightness, a complex but not filamentary morphology, a moderate expansion velocity (35 km s-1), and a low [S II]/Hα ratio (~0.15). DEM L106 is not detected in X-rays. Its shell structure is amorphous and has embedded dusty features; its expansion velocity is less than 10 km s-1. None of the three superbubbles show morphological features in the shell interior that can be identified as directly associated with SNR shocks, indicating that the SNR shocks have not encountered very dense material. We find that the [S II]/Hα ratios of X-ray–bright superbubbles are strongly dependent on the UV radiation field of the encompassed OB associations. Therefore, a tight correlation between [S II]/Hα ratio and X-ray surface brightness in superbubbles should not exist. We also find that the filamentary morphologies of superbubbles are associated with large expansion velocities and bright X-ray emission.Keywords
This publication has 24 references indexed in Scilit:
- RX J050736−6847.8: A Large Supernova Remnant around an X-Ray Binary in the Large Magellanic CloudThe Astronomical Journal, 2000
- PrefaceSymposium - International Astronomical Union, 1999
- Supernova Remnants in OB AssociationsThe Astronomical Journal, 1997
- X-Rays from Superbubbles in the Large Magellanic Cloud. III. X-Ray--dim SuperbubblesThe Astrophysical Journal, 1995
- WFPC2 observations of the double cluster NGC 1850 in the Large Magellanic CloudThe Astrophysical Journal, 1994
- Ultraviolet interstellar absorption lines in the LMC: Searching for hidden SNRsThe Astronomical Journal, 1994
- Hidden supernova remnants in the Large Magellanic Cloud H II complex N44The Astrophysical Journal, 1993
- The Magellanic Clouds: Distance, Structure, Chemical CompositionPublished by Springer Nature ,1991
- X-rays from superbubbles in the Large Magellanic CloudThe Astrophysical Journal, 1990
- Ultraviolet absorption by interstellar gas near the LMC star HD 36402 in the interstellar bubble N51DThe Astrophysical Journal, 1982