Comparing samples of SNR
ß radio-identified
SNR: dense HII regions
core-collapse SNe (young
population)
ß optically-identified SNR: low-density regions
mostly Type
Ia (old population)
ß X-ray
SNR: both, but brighter when associated to radio SNR
Radio + X-ray (+ optical)
X-ray
+ optical
1036 erg/s
L
Core-collapse
Type
Ia