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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').

10 results found.

  1. GRB 200925B: Swift-XRT refined analysis update
  2. GRB 200925B NUTTelA-TAO / BSTI Early Measurements (Preliminary)
  3. GRB 200925B: Swift-XRT refined Analysis
  4. GRB 200925B: Swift/UVOT Detection
  5. GRB 200925B: Swift-BAT refined analysis
  6. GRB 200925B: Enhanced Swift-XRT position
  7. Swift GRB 200925B: Global MASTER-Net OT detection
  8. GRB 200925B: OSN Afterglow Candidate Discovery
  9. GRB 200925B: Prompt enhanced Swift-XRT position
  10. GRB 200925B: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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