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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

9 results found.

  1. GRB 160521B: 15 GHz upper limits from AMI
  2. GRB 160521B: Swift-XRT afterglow detection
  3. Konus-Wind observation of GRB 160521B
  4. GRB 160521B: Theoretical estimate of the redshift and urgent need for further x-ray observations
  5. GRB 160521B: Swift/UVOT Upper Limits
  6. GRB 160521B: Swift-XRT observations
  7. GRB 160521B: Swift ToO observations
  8. GRB 160521B: Fermi-LAT detection
  9. GRB 160521B: Fermi GBM detection


Download all Circulars as a .tar.gz archive:
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