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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"

783 results found.

  1. GRB 121027A: Swift-XRT refined Analysis
  2. GRB 121025A: Swift-XRT observation
  3. GRB 121027A: MAXI/GSC detection 40 minutes after the Swift Trigger
  4. GRB 121025A: MAXI/GSC detection
  5. GRB 120908A: Fermi GBM detection
  6. GRB 120908A: Swift Observations
  7. GRB 120908A: MAXI/GSC detection
  8. Konus-Wind observation of GRB 120711A
  9. GRB 120711A: Fermi LAT detection
  10. GRB 120711A: GROND photometric redshift
  11. GRB 120711A: MAXI/GSC detection
  12. XRF 120626B: MAXI/GSC detection
  13. GRB 120622A: MAXI/GSC detection
  14. GRB 120614A: MAXI/GSC detection of a burst
  15. Konus-Wind observation of GRB 120528B
  16. GRB 120528C: MAXI/GSC detection
  17. GRB 120528B: MAXI/GSC detection
  18. Konus-Wind observation of GRB 120510A
  19. GRB 120510A: Swift XRT and UVOT observations
  20. GRB 120510A: MASTER follow up observations
  21. GRB 120510A: MAXI/GSC detection of a burst
  22. GRB 120424A: MAXI/GSC detection of a burst
  23. GRB 120127A / P48 Imaging
  24. GRB 120127A: MASTER optical observations
  25. GRB 120127A: MAXI/GSC detection of a probable GRB
  26. Possible detection of pre-trigger X-ray emission from GRB 111215A by MAXI/GSC
  27. XRF 111111A/MAXI J0158-744: MAXI GSC refined analysis
  28. XRF 111111A/MAXI J0158-744: MAXI GSC and SSC detection of a soft X-ray transient near SMC
  29. GRB 111024A: MAXI/GSC detection of a burst
  30. GRB 110905A / MAXI J1836-194: optical monitoring
  31. Trigger 504307: Swift detection of MAXI J1836-194
  32. MAXI/GSC detection of a short soft X-ray transient
  33. MAXI J1836-194 (originally GRB 110905A): Swift-BAT refined analysis
  34. GRB 110905A / X-ray transient MAXI J1836-194: TNT optical observation
  35. GRB 110905A: Potential BAT trigger on MAXI J1836-194
  36. GRB 110426A: Fermi GBM detection
  37. GRB 110426A: Swift/XRT non-detection
  38. GRB 110426A: MASTER synchronous with MAXI/GSC observations
  39. GRB 110426A: MAXI/GSC detection of a GRB
  40. GRB 110213B: Swift/UVOT observations
  41. GRB110213B: X-ray afterglow confirmation
  42. GRB 110213B: P60 Optical Afterglow Candidate
  43. GRB 110213B: Swift XRT observation
  44. Konus-Wind observation of GRB 110213B
  45. GRB 110213B: MAXI/GSC refined analysis
  46. GRB 110213B: MAXI/GSC detection of a probable GRB
  47. New feature in Fermi GBM GRB Ground Position Notices
  48. GRB 101225A: MAXI/GSC observations
  49. XRF 101117A, RIMOTS optical upper limits
  50. Swift detection of MAXIJ1409-619
  51. XRF 101117A: Palomar Transient Factory Observations
  52. GRB 101117B: Swift-BAT refined analysis
  53. XRF101117A: MAXI/GSC detection of a short X-ray transient
  54. GRB 100925A / MAXI J1659-152: MASTER optical observations
  55. GRB 100925A / MAXI J1659-152: WSRT Radio and Polarization Detection
  56. GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope
  57. GRB100925A/MAXI J1659-152: X-shooter identification as an X-ray binary
  58. GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation
  59. GRB 100925A / MAXI J1659-152: SARA-S Observations
  60. GRB 100925A/MAXI J1659-152: Submm observations from APEX
  61. GRB100925A/MAXI J1659-152: Galactic origin from SED analysis
  62. GRB 100925A/MAXI J1659-152 - NOT optical observations
  63. GRB 100925A / MAXI J1659-152: BOOTES-2/TELMA and IAC80 optical observations
  64. MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
  65. GRB 100823A: MAXI/GSC detection
  66. XRF 100701A : MAXI/GSC detection of a probable XRF
  67. XRF 100616a : MAXI/GSC detection of a probable XRF
  68. GRB 100510A: Fermi GBM detection/observation
  69. GRB 100510A: MAXI/GSC detection
  70. GRB 100415A: MAXI/GSC detection of a probable GRB
  71. Short X-ray Transient detected by MAXI/GSC
  72. XRF 100315A: MAXI/GSC detection of a short X-ray transient
  73. Short X-ray Transient detected by MAXI/GSC
  74. Short X-ray Transient, RIMOTS optical upper limits
  75. Short X-ray Transient Detection by MAXI/GSC
  76. IPN Triangulation of GRB091120
  77. Konus-Wind observation of GRB 091120
  78. GRB 091120: MAXI GSC detection
  79. GRB 090926B: MAXI GSC detection
  80. GRB 090831A: Suzaku WAM observation of the prompt emission
  81. GRB 090831A: IPN Triangulation
  82. GRB 090831: MAXI GSC detection
  83. SGR1806-20 bursts on 031008. Helicon detection and small error box.

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