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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"

850 results found.

  1. XRF 101117A, RIMOTS optical upper limits
  2. Swift detection of MAXIJ1409-619
  3. XRF 101117A: Palomar Transient Factory Observations
  4. GRB 101117B: Swift-BAT refined analysis
  5. XRF101117A: MAXI/GSC detection of a short X-ray transient
  6. GRB 100925A / MAXI J1659-152: MASTER optical observations
  7. GRB 100925A / MAXI J1659-152: WSRT Radio and Polarization Detection
  8. GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope
  9. GRB100925A/MAXI J1659-152: X-shooter identification as an X-ray binary
  10. GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation
  11. GRB 100925A / MAXI J1659-152: SARA-S Observations
  12. GRB 100925A/MAXI J1659-152: Submm observations from APEX
  13. GRB100925A/MAXI J1659-152: Galactic origin from SED analysis
  14. GRB 100925A/MAXI J1659-152 - NOT optical observations
  15. GRB 100925A / MAXI J1659-152: BOOTES-2/TELMA and IAC80 optical observations
  16. MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
  17. GRB 100823A: MAXI/GSC 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. Short X-ray Transient detected by MAXI/GSC
  26. Short X-ray Transient, RIMOTS optical upper limits
  27. Short X-ray Transient Detection by MAXI/GSC
  28. IPN Triangulation of GRB091120
  29. Konus-Wind observation of GRB 091120
  30. GRB 091120: MAXI GSC detection
  31. GRB 090926B: MAXI GSC detection
  32. GRB 090831A: Suzaku WAM observation of the prompt emission
  33. GRB 090831A: IPN Triangulation
  34. GRB 090831: MAXI GSC detection
  35. GRB 090812: Swift detection of a burst with an optical counterpart
  36. Konus-Wind and Konus-RF observations of GRB 090709A
  37. GRB 090205: Swift/UVOT Upper Limits
  38. GRB 090111: Swift UVOT Upper Limits
  39. GRB081230: Swift-XRT refined analysis
  40. Konus-Wind observation of GRB 051028
  41. GRB050726: Swift UVOT observations
  42. GRB050712: Swift UVOT Observation of Afterglow Emission
  43. IPN triangulation of GRB021211B (two large error boxes)
  44. GRB 990506 Radio Transient
  45. GRB 990506 optical observation
  46. GRB 990506 R band observations
  47. GRB 990506 Radio Observations
  48. GRB 990506: BATSE Observations
  49. GRB 990506, Optical Observations
  50. GRB 990506, optical observations

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