Panchromatic Observations of SN 2011dh Point to a Compact Progenitor Star

Understand

We report the discovery and detailed monitoring of X-ray emission associated with the Type IIb SN 2011dh using data from the Swift and Chandra satellites, placing it among the best studied X-ray supernovae to date.

• We further present millimeter and radio data obtained with the SMA, CARMA, and EVLA during the first three weeks after explosion.
• Combining these observations with early optical photometry, we show that the panchromatic dataset is well-described by non-thermal synchrotron emission (radio/mm) with inverse Compton scattering (X-ray) of a thermal population of optical photons.
• In this scenario, the shock partition fractions deviate from equipartition by a factor, (e_e/e_B) ~ 30.