Early optical-IR emission from GRB 041219a: neutron-rich internal shocks and a mildly magnetized external reverse shock
نویسندگان
چکیده
Very early optical and near infrared (IR) emission was discovered accompanying the long gamma-ray burst (GRB) 041219a. We show that the optical/IR flash tracking the gamma-ray lightcurve during the prompt emission could be understood as emission from neutron-rich internal shocks, as has been suggested by Fan & Wei. The early Ks-band afterglow lightcurve after the prompt phase could be well-modeled as the superposition of a reverse shock and a forward shock component. It is found that the reverse shock region is mildly magnetized. Subject headings: Gamma Rays: bursts−ISM: jets and outflows–radiation mechanisms: nonthermal
منابع مشابه
EARLY OPTICAL-INFRARED EMISSION FROM GRB 041219a: NEUTRON-RICH INTERNAL SHOCKS AND A MILDLY MAGNETIZED EXTERNAL REVERSE SHOCK
Very early optical and near-infrared emission was discovered to have accompanied the long gamma-ray burst GRB 041219a. Here we show that the optical-IR flash tracking the gamma-ray light curve during the prompt emission can be understood as emission from neutron-rich internal shocks, as has been suggested by Fan & Wei. The early Ks-band afterglow light curve after the prompt phase can be well m...
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