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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"

845 results found.

  1. GRB 101117B: Swift-BAT refined analysis
  2. XRF101117A: MAXI/GSC detection of a short X-ray transient
  3. GRB 100925A / MAXI J1659-152: MASTER optical observations
  4. GRB 100925A / MAXI J1659-152: WSRT Radio and Polarization Detection
  5. GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope
  6. GRB100925A/MAXI J1659-152: X-shooter identification as an X-ray binary
  7. GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation
  8. GRB 100925A / MAXI J1659-152: SARA-S Observations
  9. GRB 100925A/MAXI J1659-152: Submm observations from APEX
  10. GRB100925A/MAXI J1659-152: Galactic origin from SED analysis
  11. GRB 100925A/MAXI J1659-152 - NOT optical observations
  12. GRB 100925A / MAXI J1659-152: BOOTES-2/TELMA and IAC80 optical observations
  13. MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
  14. GRB 100906A: Fermi GBM observation
  15. GRB 100823A: MAXI/GSC detection
  16. GRB 100802A: Fermi GBM observation
  17. GRB 100722A: Fermi GBM detection
  18. XRF 100701A : MAXI/GSC detection of a probable XRF
  19. XRF 100616a : MAXI/GSC detection of a probable XRF
  20. GRB 100510A: Fermi GBM detection/observation
  21. GRB 100510A: MAXI/GSC detection
  22. GRB 100415A: MAXI/GSC detection of a probable GRB
  23. Short X-ray Transient detected by MAXI/GSC
  24. XRF 100315A: MAXI/GSC detection of a short X-ray transient
  25. GRB 100206A: Fermi GBM observation
  26. Short X-ray Transient detected by MAXI/GSC
  27. Short X-ray Transient, RIMOTS optical upper limits
  28. Short X-ray Transient Detection by MAXI/GSC
  29. IPN Triangulation of GRB091120
  30. Konus-Wind observation of GRB 091120
  31. GRB 091120: MAXI GSC detection
  32. GRB 090926B: MAXI GSC detection
  33. GRB 090831A: Suzaku WAM observation of the prompt emission
  34. GRB 090831A: IPN Triangulation
  35. GRB 090831: MAXI GSC detection
  36. GRB 090814C: Fermi GBM detection
  37. GRB 090813: Fermi GBM observation
  38. GRB 090728: Swift/UVOT Upper Limits
  39. GRB 090718B: Fermi GBM detection
  40. GRB 090222: Fermi GBM detection
  41. GRB081104: Swift/UVOT Upper Limits
  42. GRB 080928: Swift/UVOT observations
  43. GRB 060510B: Swift/UVOT Upper Limits
  44. GRB 050904: TAROT optical measurements
  45. HST/STIS observations of the host galaxy of GRB 980329

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