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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 221231A: 3.6m DOT optical upper limit
  2. GRB 221231A: Fermi GBM Observation
  3. GRB 221231A: Swift-XRT afterglow detection
  4. GRB 221231A: AKO Upper Limit
  5. GRB 221231A: Swift-XRT observations
  6. GRB 221231A: Swift ToO observations
  7. GRB 221231A: Swift/BAT-GUANO arcminute localization of a possibly short burst
  8. GRB 221231A: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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