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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').

13 results found.

  1. GRB 160821B: HST detection of the optical and IR counterpart
  2. GRB 160821B: 15 GHz upper limits from AMI
  3. GRB 160821B: VLA 5.0 GHz observations
  4. GRB 160821B: GTC follow-up observation
  5. GRB 160821B: WHT afterglow confirmation and redshift of candidate host
  6. GRB 160821B: Swift-BAT refined analysis
  7. GRB 160821B: Fermi GBM Detection
  8. GRB 160821B: Swift-XRT refined Analysis
  9. GRB 160821B: Swift/UVOT Upper Limits
  10. Short GRB 160821B: MASTER early optical observations
  11. GRB 160821B: Enhanced Swift-XRT position
  12. GRB 160821B: NOT optical afterglow candidate
  13. GRB 160821B: Swift detection of a short burst


Download all Circulars as a .tar.gz archive:
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