Expansion and Age of the X-ray Synchrotron-Dominated Supernova Remnant G330.2+1.0
| Autor: | Brian J. Williams, Robert Petre, Stephen P. Reynolds, Kazimierz J. Borkowski |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Physics
High Energy Astrophysical Phenomena (astro-ph.HE) Brightness Shock (fluid dynamics) Astrophysics::High Energy Astrophysical Phenomena Synchrotron radiation FOS: Physical sciences Astronomy and Astrophysics 02 engineering and technology Astrophysics Electron 01 natural sciences X ray synchrotron Magnetic field Supernova Space and Planetary Science 0103 physical sciences 0202 electrical engineering electronic engineering information engineering 020201 artificial intelligence & image processing Supernova remnant Astrophysics - High Energy Astrophysical Phenomena 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics |
| Popis: | We report new Chandra observations of one of the few Galactic supernova remnants whose X-ray spectrum is dominated by nonthermal synchrotron radiation, G330.2+1.0. We find that between 2006 and 2017, some parts of the shell have expanded by about 1%, giving a free-expansion (undecelerated) age of about 1000 yr, and implying shock velocities there of 9000 km/s for a distance of 5 kpc. Somewhat slower expansion is seen elsewhere around the remnant periphery, in particular in compact knots. Because some deceleration must have taken place, we infer that G330.2+1.0 is less than about 1000 yr old. Thus, G330.2+1.0 is one of only four Galactic core-collapse remnants of the last millennium. The large size, low brightness, and young age require a very low ambient density, suggesting expansion in a stellar-wind bubble. We suggest that in the east, where some thermal emission is seen and expansion velocities are much slower, the shock has reached the edge of the cavity. The high shock velocities can easily accelerate relativistic electrons to X-ray-emitting energies. A few small regions show highly significant brightness changes by 10% to 20%, both brightening and fading, a phenomenon previously observed in only two supernova remnants, indicating strong and/or turbulent magnetic fields. 7 pages, 4 figures, 1 Table, minor text changes to match the published version |
| Databáze: | OpenAIRE |
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