Keywords
ISM: individual objects (HB 21)
radiation mechanisms: non-thermal
radiation mechanisms: thermal
radio continuum: general
surveys
Astrophysics - Galaxy Astrophysics
radiation mechanisms: non-thermal
radiation mechanisms: thermal
radio continuum: general
surveys
Astrophysics - Galaxy Astrophysics
How to Cite
Spectra of the HB 21 supernova remnant: Evidence of spectrum flattening at the low frequencies. (2012). Revista Mexicana De Astronomía Y Astrofísica, 48(1), 53-60. https://astronomia.unam.mx/journals/rmxaa/article/view/2012rmxaa..48...53b
Abstract
We use observations of the continuum radio emission at 1420, 820, 408, 34.5 and 22 MHz to estimate the mean brightness temperatures of the HB 21 supernova remnant (SNR) at five frequencies. We also present mean spectral index of HB1. The spectra of HB 21 are estimated from mean temperatures versus frequency plots for 1420, 820, 408, 34.5 and 22 MHz. We also present T-T plots of three frequency pairs: between 1420-34.5, 1420-22, 34.5-22 MHz. We notice flatter spectral indices at frequencies below 408 MHz. Probably this is due to the absorption by thermal plasma at low frequencies.Similar Articles
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