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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').

12 results found.

  1. GRB 180904A: BOOTES-2/TELMA early observations
  2. GRB 180904A: AbAO optical upper limit
  3. GRB 180904A: Swift/UVOT Upper Limits
  4. GRB 180904A: RATIR Optical and NIR Observations
  5. GRB 180904A: Swift-BAT refined analysis
  6. GRB 180904A: Swift-XRT refined Analysis
  7. GRB 180904A: LT early observations
  8. GRB 180904A: SAO RAS optical observations
  9. GRB 180904A: OSN observations
  10. GRB 180904A: Enhanced Swift-XRT position
  11. GRB 180904A: NOT optical observations, candidate host galaxy
  12. GRB 180904A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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