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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 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  2. GRB 230409B: Mondy optical upper limit
  3. GRB 230409B: OHP/T193 optical upper limit
  4. GRB 230409B: Swift-XRT refined Analysis
  5. GRB 230409B: Swift-BAT refined analysis
  6. Swift GRB 230409B: Global MASTER-Net observations report
  7. GRB 230409B: Swift/UVOT Detection
  8. GRB 230409B: Enhanced Swift-XRT position
  9. GRB 230409B: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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