English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present broad-band radio observations of the afterglow of GRB000301C,spanning from 1.4 to 350 GHz for the period of 3 to 83 days after the burst.This radio data, in addition to measurements at the optical bands, suggest thatthe afterglow arises from a collimated outflow, i.e. a jet. To test thishypothesis in a self-consistent manner, we employ a global fit and find that amodel of a jet, expanding into a constant density medium (ISM+jet), providesthe best fit to the data. A model of the burst occurring in a wind-shapedcircumburst medium (wind-only model) can be ruled out, and a wind+jet modelprovides a much poorer fit of the optical/IR data than the ISM+jet model. Inaddition, we present the first clear indication that the reported fluctuationsin the optical/IR are achromatic with similar amplitudes in all bands, andpossibly extend into the radio regime. Using the parameters derived from theglobal fit, in particular a jet break time, t_{jet}=7.5 days, we infer a jetopening angle of \theta=0.2, and consequently the estimate of the emittedenergy in the GRB itself is reduced by a factor of 50 relative to the isotropicvalue, giving E=1.1 \times 10^{51} ergs.Comment: 8 pages, ApJ submitte

A Jet Model for the Afterglow Emission from GRB 000301C