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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').

10 results found.

  1. GRB 141020A: Continued Mondy Observations, optical upper limit
  2. GRB 141020A: AAO optical upper limit
  3. GRB 141020A: Khureltogot optical upper limit
  4. GRB 141020A: Mondy optical observations
  5. GRB 141020A: Swift-BAT refined analysis
  6. GRB 141020A: Swift-XRT refined Analysis
  7. GRB 141020A: 1.4 GHZ observation
  8. GRB 141020A: Swift/UVOT Detection
  9. GRB 141020A: Enhanced Swift-XRT position
  10. GRB 141020A: Swift detection of a burst with an optical counterpart


Download all Circulars as a .tar.gz archive:
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