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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32 results found.

  1. GRB 221009A: Armchair Energetics
  2. GRB 180720B: Testing the universality of the newly born neutron star in BdHNe
  3. GRB 160625B: Global MASTER-Crimea prompt optical emission detection (fwd)
  4. GRB 160625B: TSHAO optical observations
  5. GRB 160625B: RTT150 optical observations
  6. GRB 160625B: SAO RAS monitoring
  7. GRB 160625B: LCOGT FTN observations
  8. GRB 160625B: TSHAO optical observations, correction GCN 19619
  9. GRB 160625B: TSHAO optical observations
  10. GRB 160625B CALET Gamma-Ray Burst Monitor detection
  11. GRB 160625B: SMARTS optical/IR afterglow observations
  12. Pi of the Sky detection of an optical flash accompanying GRB 160625B
  13. GRB 160625B: Global MASTER-Net prompt optical emission detection
  14. GRB 160625B: SAO RAS optical observations
  15. GRB 160625B: 15 GHz detection from AMI
  16. GRB 160625B: VLA Detection
  17. GRB 160625B: TSHAO optical observations
  18. Konus-Wind observation of GRB 160625B
  19. GRB 160625B: Mini-MegaTORTORA detection of bright optical flash simultaneous with LAT event
  20. GRB 160625B: RATIR Optical and NIR Observations
  21. GRB 160625B: TNG redshift confirmation
  22. GRB 160625B: VLT/X-shooter redshift
  23. GRB 160625B: MITSuME Ishigakijima Optical Observation
  24. GRB 160625A: Swift-BAT refined analysis
  25. GRB 160625B: Swift/UVOT Detection
  26. GRB 160625B: RATIR Optical and NIR Afterglow Detection
  27. GRB 160625B: Fermi GBM refined analysis
  28. GRB 160625B: Fermi-LAT refined analysis
  29. GRB 160625B: Swift-XRT afterglow detection
  30. GRB 160625B: Tiled Swift observations
  31. GRB 160625B: Fermi GBM initial observations
  32. GRB 160625B: Fermi-LAT detection of a bright burst

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