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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').

8 results found.

  1. GRB 210606A: Fermi GBM detection
  2. GRB 210606A: Swift-XRT afterglow detection
  3. GRB 210606A: 1.5m OSN optical upper limit
  4. GRB 210606A: Swift ToO observations
  5. Fermi GRB 210606A: DDOTI Upper Limits on the Afterglow
  6. GRB 210606A: Swift/BAT-GUANO detection and arcminute localization
  7. Fermi GRB 210606A: Global MASTER-Net observations report
  8. GRB 210606A: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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