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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"

855 results found.

  1. GRB 110426A: MASTER synchronous with MAXI/GSC observations
  2. GRB 110426A: MAXI/GSC detection of a GRB
  3. GRB 110213B: Swift/UVOT observations
  4. GRB110213B: X-ray afterglow confirmation
  5. GRB 110213B: P60 Optical Afterglow Candidate
  6. GRB 110213B: Swift XRT observation
  7. Konus-Wind observation of GRB 110213B
  8. GRB 110213B: MAXI/GSC refined analysis
  9. GRB 110213B: MAXI/GSC detection of a probable GRB
  10. New feature in Fermi GBM GRB Ground Position Notices
  11. GRB 101225A: MAXI/GSC observations
  12. XRF 101117A, RIMOTS optical upper limits
  13. Swift detection of MAXIJ1409-619
  14. XRF 101117A: Palomar Transient Factory Observations
  15. GRB 101117B: Swift-BAT refined analysis
  16. XRF101117A: MAXI/GSC detection of a short X-ray transient
  17. GRB 100925A / MAXI J1659-152: MASTER optical observations
  18. GRB 100925A / MAXI J1659-152: WSRT Radio and Polarization Detection
  19. GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope
  20. GRB100925A/MAXI J1659-152: X-shooter identification as an X-ray binary
  21. GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation
  22. GRB 100925A / MAXI J1659-152: SARA-S Observations
  23. GRB 100925A/MAXI J1659-152: Submm observations from APEX
  24. GRB100925A/MAXI J1659-152: Galactic origin from SED analysis
  25. GRB 100925A/MAXI J1659-152 - NOT optical observations
  26. GRB 100925A / MAXI J1659-152: BOOTES-2/TELMA and IAC80 optical observations
  27. MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
  28. GRB 100823A: MAXI/GSC detection
  29. GRB 100704: Swift/UVOT Upper Limits
  30. XRF 100701A : MAXI/GSC detection of a probable XRF
  31. XRF 100616a : MAXI/GSC detection of a probable XRF
  32. GRB 100615A: Swift/UVOT Upper Limits
  33. GRB 100510A: Fermi GBM detection/observation
  34. GRB 100510A: MAXI/GSC detection
  35. GRB 100415A: MAXI/GSC detection of a probable GRB
  36. Short X-ray Transient detected by MAXI/GSC
  37. XRF 100315A: MAXI/GSC detection of a short X-ray transient
  38. Short X-ray Transient detected by MAXI/GSC
  39. Short X-ray Transient, RIMOTS optical upper limits
  40. Short X-ray Transient Detection by MAXI/GSC
  41. IPN Triangulation of GRB091120
  42. Konus-Wind observation of GRB 091120
  43. GRB 091120: MAXI GSC detection
  44. GRB 090926B: MAXI GSC detection
  45. GRB 090831A: Suzaku WAM observation of the prompt emission
  46. GRB 090831A: IPN Triangulation
  47. GRB 090831: MAXI GSC detection
  48. GRB 090621: Swift/UVOT Upper Limits
  49. GRB080916A: Refined Swift/UVOT Observations
  50. GRB 080703: UVOT Follow-Up Observation
  51. GRB 080310: Swift/UVOT Refined Analysis
  52. Transient 080109/ SN 2008D, metallicity of the host galaxy
  53. Swift/UVOT observations of GRB070721B optical afterglow.
  54. Swift/UVOT refined analysis of GRB070529
  55. GRB 060109: Swift/UVOT upper limits

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