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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 151228B: AbAO optical upper limit
  2. GRB 151228B: Swift/UVOT Detection
  3. GRB 151228B: MITSuME Akeno optical upper limits
  4. GRB 151228B: Fermi GBM observation
  5. GRB 151228B: Swift-BAT refined analysis
  6. GRB 151228B: Swift-XRT refined Analysis
  7. GRB 151228B: Enhanced Swift-XRT position
  8. GRB 151228B: Swift detection of a burst with an optical detection


Download all Circulars as a .tar.gz archive:
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