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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. Konus-Wind observation of GRB 100522A
  2. GRB 100522A: GROND observations, upper limits
  3. GRB 100522A: Fermi GBM observation
  4. GRB 100522A: Swift XRT refined analysis
  5. GRB 100522A, Swift-BAT refined analysis
  6. GRB 100522A: Enhanced Swift-XRT position
  7. GRB 100522A: NIR observations from CAHA
  8. GRB 100522A: BOOTES-2 optical limit
  9. GRB 100522A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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