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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide.

  • Circulars are brief, citeable, and human-readable.
  • Circulars can announce observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans.
  • Circulars report on high-energy, multi-messenger, and variable or transient astrophysical events.

Circulars allow the GRB community to post messages (by email, or by submitting a web form) to a public list where they are distributed rapidly to the entire GRB community and archived permanently. These prose-style messages allow the community to coordinate and make optimum use of its limited resources.

For more details on how to use GCN Circulars, see:

  • Subscribing to receive GCN Circulars by email
  • Submitting to post your own GCN Circulars
  • Style Guide for how to write an effective GCN Circular
  • Corrections for how to make minor corrections to archived GCN Circulars
  • Archive for how to search for and browse GCN Circulars

Go to GCN Circulars Archive

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