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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').

17 results found.

  1. GRB 160225A: TSHAO optical afterglow detection
  2. GRB 160225A: LOAO optical upper limit
  3. GRB 160225A: Continued RATIR Optical and NIR Observations
  4. GRB 160225A: Swift-BAT refined analysis
  5. GRB 160225A: MASTER-Amur observations
  6. GRB 160225A: RATIR Optical and NIR Observations
  7. GRB 160225A: Swift/UVOT Upper Limits
  8. GRB 160225A: Xinglong TNT optical observation
  9. GRB 160225A: Swift-XRT refined Analysis
  10. GRB 160225A: NOT optical observations
  11. GRB 160225A: WHT LIRIS observations
  12. GRB 160225A: MITSuME Okayama Optical Observation
  13. GRB 160225A: MITSuME Akeno Optical Observation
  14. GRB 160225A: TSHAO optical upper limit
  15. GRB 160225A: Enhanced Swift-XRT position
  16. GRB 160225A: MASTER-Amur early observations
  17. GRB 160225A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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