6 research outputs found
Spatially Varying X-ray Synchrotron Emission in SN 1006
A growing number of both galactic and extragalactic supernova remnants show
non-thermal (non-plerionic) emission in the X-ray band. New synchrotron models,
realized as SRESC and SRCUT in XSPEC 11, which use the radio spectral index and
flux as inputs and include the full single-particle emissivity, have
demonstrated that synchrotron emission is capable of producing the spectra of
dominantly non-thermal supernova remnants with interesting consequences for
residual thermal abundances and acceleration of particles. In addition, these
models deliver a much better-constrained separation between the thermal and
non-thermal components, whereas combining an unconstrained powerlaw with modern
thermal models can produce a range of acceptable fits. While synchrotron
emission can be approximated by a powerlaw over small ranges of energy, the
synchrotron spectrum is in fact steepening over the X-ray band. Having
demonstrated that the integrated spectrum of SN 1006, a remnant dominated by
non-thermal emission, is well described by synchrotron models I now turn to
spatially resolved observations of this well studied remnant. The synchrotron
models make both spectral and spatial predictions, describing how the
non-thermal emission varies across the remnant. Armed with spatially resolved
non-thermal models and new thermal models such as VPSHOCK we can now dissect
the inner workings of SN 1006.Comment: 4 pages, 4 figures. To appear in "Young Supernova Remnants" the 11th
Annual October Maryland Astrophysics Conference AIP eds. Steve Holt and Una
Hwan
Chandra Smells a RRAT: X-ray Detection of a Rotating Radio Transient
"Rotating RAdio Transients" (RRATs) are a newly discovered astronomical
phenomenon, characterised by occasional brief radio bursts, with average
intervals between bursts ranging from minutes to hours. The burst spacings
allow identification of periodicities, which fall in the range 0.4 to 7
seconds. The RRATs thus seem to be rotating neutron stars, albeit with
properties very different from the rest of the population. We here present the
serendipitous detection with the Chandra X-ray Observatory of a bright
point-like X-ray source coincident with one of the RRATs. We discuss the
temporal and spectral properties of this X-ray emission, consider counterparts
in other wavebands, and interpret these results in the context of possible
explanations for the RRAT population.Comment: 5 pages, 2 b/w figures, 1 color figure. To appear in the proceedings
of "Isolated Neutron Stars", Astrophysics & Space Science, in pres