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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

18509 results found.

  1. GRB 100526A: optical upper limit
  2. GRB 100528A: Faulkes Telescope North Detection
  3. GRB 100528A: GROND detection in all bands
  4. GRB 100528A: NOT optical observation
  5. Swift UVOT and UVOT-enhanced XRT position for GRB 100528A
  6. GRB100526B: GROND Upper limits
  7. GRB 100526B: Swift/UVOT Upper Limits
  8. GRB 100526A: Swift/UVOT Upper Limits
  9. GRB 100526A: Gemini/NIRI infrared afterglow candidate
  10. GRB 100526A: NOT optical upper limit
  11. GRB 100526B: Swift XRT/UVOT observations
  12. GRB 100526A: Enhanced Swift-XRT position
  13. GRB 100526A: MASTER-Net optical alert observations
  14. GRB 100526A: Swift detection of a burst
  15. GRB 100418A: Subaru late-time optical imaging and spectroscopy
  16. GRB 100522A: Enhanced Swift-XRT position
  17. GRB 100522A: NIR observations from CAHA
  18. GRB 100522A: Swift detection of a burst
  19. GRB 100418A: CrAO optical observations
  20. GRB 100518A: GROND afterglow observation and photo-z
  21. GRB 100518A: Swift-XRT refined analysis
  22. GRB 100518A: BOOTES-3 optical observations
  23. GRB 100518A: Swift target of opportunity observation of the INTEGRAL burst
  24. GRB 100513A: MITSuME Akeno Optical Observation
  25. Swift Trigger 422437 is probably not a GRB
  26. GRB 100517A: MASTER-Net wide field camera prompt optical observations
  27. GRB 100514A: optical afterglow confirmation
  28. GRB 100514A: Swift/UVOT Observations
  29. GRB 100514A: YNAO-GMG observations
  30. GRB 100514A: Swift XRT refined analysis
  31. GRB 100514A: Enhanced Swift-XRT position
  32. GRB 100514A: Swift detection of a burst
  33. GRB 100513A: Swift/UVOT upper limits
  34. GRB 100513A, RIMOTS optical upper limits
  35. GRB 100513A: Swift XRT refined analysis
  36. GRB 100513A: Enhanced Swift-XRT position
  37. GRB 100513A: Lick observations and R-band dropout
  38. GRB 100513A: SARA-N Upper Limit
  39. GRB 100513A: Swift detection of a burst
  40. GRB 100511A: Super-LOTIS early observations
  41. GRB100504A: Optical upper limits at IAO
  42. GRB 100511A, RIMOTS optical upper limits
  43. Trigger 421695: Swift detection of a possible burst
  44. GRB 100508A: GROND Detection of the optical afterglow
  45. GRB 100508A: Swift-XRT Refined analysis
  46. GRB 100508A: Enhanced Swift-XRT position
  47. GRB100508A: Swift/UVOT Detection of the Afterglow
  48. GRB 100508A: ROTSE-III Optical Limits
  49. GRB 100508A: Swift detection of a burst
  50. GRB 100418A: Keck imaging
  51. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  52. GRB 100504A: Swift/UVOT Observations
  53. GRB 100504A: Enhanced Swift-XRT position
  54. GRB 100504A: GROND Upper limits
  55. GRB 100504A: SARA-South Upper Limit
  56. GRB 100504A: Swift detection of a burst
  57. INTEGRAL observations of Swift GRB trigger 421072
  58. Trigger 421072: Possible Swift detection of a GRB or transient
  59. GRB 100420A: Terskol optical upper limit
  60. GRB 100427A: Swift XRT and UVOT Upper Limits
  61. GRB 100414A : EVLA Radio Detection
  62. GRB 100414A : WSRT Radio Detection
  63. GRB 100423A: CrAO optical observations
  64. GRB 100418A: Terskol optical observations
  65. GRB 100424A: CrAO optical observations
  66. GRB 100424A: NIR Afterglow Confirmation
  67. GRB 100424A: Gemini/NIRI H-band observations
  68. GRB100425A: Swift/UVOT Upper Limits
  69. GRB 100424A: Swift/UVOT Upper Limits
  70. GRB 100424A: Liverpool Telescope Upper Limits
  71. GRB 100425A: Enhanced Swift-XRT position
  72. GRB 100425A: GROND afterglow observation
  73. GRB 100424A: Gemini/NIRI Candidate Afterglow
  74. GRB 100424A: D50 optical limits
  75. GRB 100425A: candidate optical afterglow from the VLT
  76. GRB100424A: MITSuME optical upper limits
  77. GRB100423A: MITSuME optical upper limits
  78. GRB 100424A : Lulin early z'-band upper limit
  79. GRB 100424A: GROND Upper Limits
  80. GRB 100424A: PAIRITEL NIR Upper Limits
  81. GRB 100425A: Swift detection of a burst
  82. GRB 100424A: WHT z-band observations
  83. GRB 100424A: NOT optical observations
  84. GRB 100424A: Enhanced Swift-XRT position
  85. GRB 100424A: Swift detection of a burst
  86. GRB 100420A: GRT Optical Observation
  87. Swift Trigger 420256: D50 optical limits
  88. Swift Trigger 420256: IAC80 R-band observations
  89. Swift Trigger 420256: BOOTES-2 observations
  90. Trigger 420256: Swift detection of a possible GRB
  91. GRB 100423A: GROND discovery of afterglow
  92. GRB100418A: REM possible afterglow detection
  93. GRB 100418A: Continuing Swift/UVOT Observations
  94. GRB100420A: MITSuME optical upper limits
  95. GRB 100414A: CFHT optical observations
  96. GRB 100420A: Swift/UVOT Upper Limits
  97. GRB 100420A: Enhanced Swift-XRT position
  98. GRB 100418A: SARA second epoch
  99. GRB 100420A: SARA Upper Limits
  100. GRB 100418A: optical observations

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