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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').

6 results found.

  1. GRB 230204A: Swift-BAT refined analysis
  2. GRB 230204A: Swift/UVOT Upper Limits
  3. GRB 230204A: Swift-XRT refined Analysis
  4. GRB 230204A/Swift J1552.8-5055: LCOGT Optical Counterpart Candidate
  5. GRB 230204A: Enhanced Swift-XRT position
  6. GRB 230204A: Swift detection of a possible burst (or possible transient Swift J1552.8-5055)


Download all Circulars as a .tar.gz archive:
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