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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').

12 results found.

  1. GRB 170903A: 15 GHz upper limits from AMI
  2. GRB 170903A: Fermi GBM observation
  3. GRB 170903A: Swift/UVOT Upper Limits
  4. GRB 170903A: UAFO /ISON optical upper limit
  5. GRB 170903A: MITSuME Okayama upper limits
  6. GRB 170903A: Swift-XRT refined Analysis
  7. GRB 170903A: Host galaxy redshift from OSIRIS/GTC
  8. GRB 170903A: Enhanced Swift-XRT position
  9. GRB 170903A: Swift-BAT refined analysis
  10. GRB 170903A: Nanshan optical upper limit
  11. GRB 170903A: Swift-XRT observations
  12. GRB 170903A: Swift detection of a burst

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