HR: 10:30h
AN: SP52A-01 [Abstracts]
TI: Spatially Resolved Observations Confirm Transition Radiation in a Solar Radio Burst
AU: * Nita, G M
EM: gnita@njit.edu
AF: New Jersey Institute of Technology, University Heights, Newark, NJ 07102-1982 United States
AU: Gary, D E
EM: dgary@njit.edu
AF: New Jersey Institute of Technology, University Heights, Newark, NJ 07102-1982 United States
AU: Fleishman, G D
EM: gfleishm@nrao.edu
AF: New Jersey Institute of Technology, University Heights, Newark, NJ 07102-1982 United States
AU: Fleishman, G D
EM: gfleishm@nrao.edu
AF: National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 United States
AB:
We report the first confirmed spatially resolved observation of the
decimetric Resonant Transition Radiation (RTR) in a solar radio
burst, which is an unavoidable by-product of microturbulences
present in dense enough astrophysical plasmas. A number of recent
publications, based mainly on studies of individual events, found
some indication that RTR may be produced in solar radio bursts. Most
recently, we have described the observational characteristics
expected for RTR in the case of solar radio bursts (Fleishman, Nita,
and Gary, 2005, ApJ, 620, 506), and found that the
correlations and associations predicted for total power data are
indeed present in the decimetric components of a statistical sample
of two-component solar continuum radio bursts. However,
interpretations based on non-imaging total power data remain
indirect (and, thus, ambiguous) until they can be combined with
direct imaging evidence from multi-wavelength spatially resolved
observations, which so far have been missing in the previous
studies. The spectral components of such RTR candidate bursts (one
at centimeter wavelengths due to the usual gyrosynchrotron
mechanism, and one at decimeter wavelengths suspected as RTR), must
be co-spatial to allow an unambiguous RTR interpretation. This study
presents comprehensive (radio, optical, and soft X-ray) spatially
resolved observations for one of these bursts, which, together with
the already demanding spectral and polarization correlations found
previously, provide direct evidence for the presence of RTR.
UR: http://www.journals.uchicago.edu/ApJ/journal/issues/ApJ/v620n1/61376/61376.html
DE: 7519 Flares
DE: 7534 Radio emissions
SC: Solar Physics Division - AAS [SP]
MN: 2005 Joint Assembly