Are low-luminosity gamma-ray bursts generated by relativistic jets?

Omer Bromberg*, Ehud Nakar, Tsvi Piran

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Low-luminosity gamma-ray bursts (ll-GRBs) constitute a subclass of GRBs that play a central role in the GRB-supernova connection. While ll-GRBs differ from typical long GRBs (LGRBs) in many aspects, they also share some common features. Therefore, the question whether the gamma-ray emission of ll-GRBs and LGRBs has a common origin is of great interest. Here we address this question by testing whether ll-GRBs, like LGRBs according to the Collapsar model, can be generated by relativistic jets that punch holes in the envelopes of their progenitor stars. The Collapsar model predicts that the durations of most observed bursts will be comparable to, or longer than, the time it takes the jets to break out of the star. We calculate the jet breakout times of ll-GRBs and compare them to the observed durations. We find that there is a significant excess of ll-GRBs with durations that are much shorter than the jet breakout time and that these are inconsistent with the Collapsar model. We conclude that the processes that dominate the gamma-ray emission of ll-GRBs and of LGRBs are most likely fundamentally different.

Original languageEnglish
Article numberL55
JournalAstrophysical Journal Letters
Issue number2
StatePublished - 1 Oct 2011


  • ISM: jets and outflows
  • gamma-ray burst: general
  • methods: analytical
  • stars: WolfRayet
  • supernovae: general


Dive into the research topics of 'Are low-luminosity gamma-ray bursts generated by relativistic jets?'. Together they form a unique fingerprint.

Cite this