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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"

28039 results found.

  1. GRB 100526B: Swift/UVOT Upper Limits
  2. GRB 100526A: Swift/UVOT Upper Limits
  3. GRB 100526A: Gemini/NIRI infrared afterglow candidate
  4. GRB 100526A: NOT optical upper limit
  5. GRB 100526A: Swift XRT refined analysis
  6. GRB 100526B: Swift-BAT refined analysis
  7. GRB 100526B: Swift XRT/UVOT observations
  8. GRB 100526A: Swift-BAT refined analysis
  9. GRB 100526A: Enhanced Swift-XRT position
  10. GRB 100526A: MASTER-Net optical alert observations
  11. GRB 100526A: Swift detection of a burst
  12. GRB100522A: Suzaku WAM observation of the prompt emission
  13. GRB 100418A: Subaru late-time optical imaging and spectroscopy
  14. GRB 100522A: GROND observations, upper limits
  15. GRB 100522A: Fermi GBM observation
  16. GRB 100522A: Swift XRT refined analysis
  17. GRB 100522A, Swift-BAT refined analysis
  18. GRB 100522A: Enhanced Swift-XRT position
  19. GRB 100522A: NIR observations from CAHA
  20. GRB 100522A: Swift detection of a burst
  21. GRB 100418A: CrAO optical observations
  22. GRB 100518A: GROND afterglow observation and photo-z
  23. GRB 100518A: Swift-XRT refined analysis
  24. GRB 100518A: optical afterglow decay
  25. GRB 100518A: BOOTES-3 optical observations
  26. Update to the configuration of the Fermi-LAT onboard GRB search
  27. GRB 100518A: Swift target of opportunity observation of the INTEGRAL burst
  28. GRB 100513A: MITSuME Akeno Optical Observation
  29. GRB 100518A: a long GRB detected with INTEGRAL
  30. Swift Trigger 422437 is probably not a GRB
  31. GRB 100517A: MASTER-Net wide field camera prompt optical observations
  32. GRB 100514A: optical afterglow confirmation
  33. GRB 100514A: Swift/UVOT Observations
  34. GRB 100514A: YNAO-GMG observations
  35. GRB 100514A: Swift XRT refined analysis
  36. GRB 100514A: Enhanced Swift-XRT position
  37. GRB 100514A: Swift-BAT refined analysis
  38. GRB 100514A: Swift detection of a burst
  39. GRB 100513A: Swift/UVOT upper limits
  40. GRB 100513A, RIMOTS optical upper limits
  41. GRB 100513A: Swift XRT refined analysis
  42. GRB 100513A: Swift-BAT refined analysis
  43. GRB 100513A: Enhanced Swift-XRT position
  44. GRB 100513A: SARA-N Upper Limit
  45. GRB 100513A: Swift detection of a burst
  46. GRB 100510A: Fermi GBM detection/observation
  47. GRB 100511A: Fermi GBM detection/observation
  48. GRB 100511A: Super-LOTIS early observations
  49. Swift-BAT trigger 421695 is likely not astrophysical
  50. GRB100504A: Optical upper limits at IAO
  51. GRB 100510A: MAXI/GSC detection
  52. GRB 100511A, RIMOTS optical upper limits
  53. Trigger 421695: Swift detection of a possible burst
  54. GRB100503A: Suzaku WAM observation of the prompt emission
  55. GRB 100508A: GROND Detection of the optical afterglow
  56. GRB 100508A: Swift-XRT Refined analysis
  57. GRB 100508A: Swift-BAT refined analysis
  58. GRB 100508A: Enhanced Swift-XRT position
  59. GRB100508A: Swift/UVOT Detection of the Afterglow
  60. GRB 100508A: ROTSE-III Optical Limits
  61. GRB 100508A: Swift detection of a burst
  62. GRB 100418A: Keck imaging
  63. GRB 100418A: RTT150 optical observations
  64. Swift-BAT refined analysis of trigger 421262
  65. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  66. GRB 100504A: Swift/UVOT Observations
  67. GRB 100504A: Swift-XRT refined analysis
  68. GRB 100504A: Enhanced Swift-XRT position
  69. GRB 100504A: GROND Upper limits
  70. GRB 100504A: Swift-BAT refined analysis
  71. GRB 100504A: SARA-South Upper Limit
  72. GRB 100503A: Fermi GBM detection
  73. GRB 100504A: Swift detection of a burst
  74. INTEGRAL observations of Swift GRB trigger 421072
  75. GRB100423A : Suzaku WAM observation of the prompt emission
  76. Trigger 421072: Possible Swift detection of a GRB or transient
  77. GRB 100420A: Terskol optical upper limit
  78. GRB 100427A: Swift XRT and UVOT Upper Limits
  79. GRB 100427A: Fermi GBM detection
  80. GRB 100414A : EVLA Radio Detection
  81. GRB 100414A : WSRT Radio Detection
  82. GRB 100423A: CrAO optical observations
  83. GRB 100418A: Terskol optical observations
  84. GRB 100424A: CrAO optical observations
  85. GRB 100424A: NIR Afterglow Confirmation
  86. GRB 100425A: Swift XRT refined analysis
  87. GRB 100424A: Gemini/NIRI H-band observations
  88. GRB100425A: Swift/UVOT Upper Limits
  89. GRB 100424A: Swift/UVOT Upper Limits
  90. GRB 100424A: Liverpool Telescope Upper Limits
  91. GRB 100425A: Enhanced Swift-XRT position
  92. GRB 100425A: Swift-BAT refined analysis
  93. GRB 100425A: GROND afterglow observation
  94. GRB 100424A: Gemini/NIRI Candidate Afterglow
  95. GRB 100424A: D50 optical limits
  96. GRB 100425A: candidate optical afterglow from the VLT
  97. GRB100424A: MITSuME optical upper limits
  98. GRB100423A: MITSuME optical upper limits
  99. GRB 100424A : Lulin early z'-band upper limit
  100. GRB 100424A: GROND Upper Limits

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Download all Circulars as a .tar.gz archive (updated once a day):
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