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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"

18431 results found.

  1. GRB 100713A: Swift XRT refined analysis
  2. GRB 100713A : IRSF/SIRIUS NIR upper limits
  3. GRB100713A: Swift/UVOT observations
  4. GRB 100713A: GROND upper limits
  5. GRB 100713A: optical upper limit
  6. GRB 100713A: TELMA and 1.5m OSN optical observations
  7. GRB100713A: Swift X-ray afterglow detection
  8. GRB 100628A: Chandra observations
  9. GRB 100628A: Swift XRT/UVOT refined analysis
  10. Tentative redshift of GRB100704A from Swift-XRT data
  11. Konus-Wind observation of GRB 100704A
  12. GRB 100704A: Swift XRT refined analysis
  13. GRB 100704: Swift/UVOT Upper Limits
  14. GRB 100704A: Fermi GBM observation
  15. GRB 100704A: Swift-BAT refined analysis
  16. GRB100704A: MOA optical upper limit
  17. GRB 100704A: Enhanced Swift-XRT position
  18. GRB 100704A: Swift detection of a burst
  19. GRB 100702A, Swift-BAT refined analysis
  20. GRB 100702A: Swift XRT refined analysis
  21. Swift/UVOT observations of GRB100702A - correction
  22. Swift/UVOT observations of GRB100702A
  23. GRB 100702: ROTSE-III Optical Limits
  24. GRB 100702A: Swift detection of a short burst
  25. GRB 100615A: Chandra X-ray ToO Observation
  26. GRB 100213B: Detection of Fading Optical Afterglow
  27. GRB 100625A: Fermi GBM detection
  28. GRB 100628A: Swift XRT refined position
  29. GRB100625A: GROND confirmation of constant source
  30. GRB100628A : MOA optical upper limit
  31. GRB 100628A: Swift/UVOT Upper Limits
  32. GRB 100628A: Swift XRT detection of a possible X-ray afterglow
  33. GRB 100628A: INTEGRAL SPI-ACS light curve
  34. GRB 100628A: Swift-BAT refined analysis
  35. GRB 100628A: Swift detection of a short hard burst
  36. Swift-BAT trigger 426048 is not a burst
  37. GRB 100614A: CrAO optical limit
  38. GRB 100625A: Swift/UVOT Upper Limits
  39. GRB 100625A: Swift-BAT refined analysis
  40. Konus-Wind observation of GRB 100625A
  41. GRB 100625A : IRSF/SIRIUS NIR upper limit
  42. GRB 100625A: Swift-XRT Team refined analysis
  43. GRB 100625A: Enhanced Swift-XRT position
  44. GRB100625A : MOA optical upper limit
  45. GRB 100625A: Swift detection of a short hard burst
  46. GRB 100418A: late time optical observations
  47. Konus-Wind observation of GRB 100621A
  48. GRB 100621A: IRSF/SIRIUS NIR Observation
  49. GRB 100621A MOA-II optical limit
  50. GRB 100621A: Swift/UVOT observations
  51. GRB 100621A: Swift XRT refined analysis
  52. GRB 100621A: Swift-BAT refined analysis
  53. GRB 100621A: GROND observation of bright NIR afterglow
  54. GRB 100621A: Enhanced Swift-XRT position
  55. GRB 100621A: Prompt enhanced Swift-XRT position
  56. GRB 100621A: ROTSE-III Optical Limits
  57. GRB 100621A: Swift detection of a burst
  58. GRB 100606A: Optical Limits
  59. GRB 100619A: Fermi GBM detection
  60. GRB 100619A: Swift/UVOT Upper Limits
  61. GRB 100619A: Swift-XRT refind analysis
  62. GRB 100619A: Enhanced Swift-XRT position
  63. GRB 100619A: Swift-BAT refined analysis
  64. GRB 100619A: Swift detection of a burst
  65. GRB 100615A: Swift/UVOT Upper Limits
  66. GRB 100614A: Swift/UVOT Upper Limits
  67. GRB 100614A: MASTER-Net optical alert observations
  68. GRB 100614A: Swift-BAT refined analysis
  69. GRB 100615A: Fermi GBM detection
  70. GRB 100615A: Swift-BAT refined analysis
  71. GRB 100614A: Enhanced Swift-XRT position
  72. GRB 100615A: Enhanced Swift-XRT position
  73. GRB 100615A: Swift-XRT refined analysis
  74. GRB 100614A: Swift-XRT refined analysis
  75. GRB 100615A: PAIRITEL NIR Upper Limits
  76. GRB 100615A: Swift detection of a burst
  77. GRB 100614A: Liverpool Telescope Observations
  78. GRB 100614A: Swift detection of a burst
  79. GRB 100606A: Suzaku WAM observation of the prompt emission
  80. Trigger 424161: Swift/BAT trigger on XTE J1946+274/GRO J1944+26
  81. Konus-Wind observation of GRB 100606A
  82. Radio detection of GRB100418a with ATCA
  83. GRB 100606A: Swift/UVOT Upper Limits
  84. GRB 100606A Swift-XRT refined analysis
  85. GRB 100606A: Swift-BAT refined analysis
  86. GRB 100606A: Enhanced Swift-XRT position
  87. Swift Trigger 424040 is not a GRB
  88. GRB 100606A: Prompt enhanced Swift-XRT position
  89. GRB 100606A: Swift detection of a burst
  90. Swift detection of outburst from the SFXT IGR J18410-0535
  91. GRB 100111A: Maidanak optical observations
  92. GRB 100418A: Maidanak optical observations
  93. GRB 100513A: CrAO optical observations
  94. GRB 100514A: CrAO optical observations
  95. GRB 100526A: optical upper limit
  96. Swift UVOT and UVOT-enhanced XRT position for GRB 100528A
  97. GRB100526B: GROND Upper limits
  98. GRB 100526B: Swift-XRT confirmation of fading afterglow
  99. GRB 100526B: Swift/UVOT Upper Limits
  100. GRB 100526A: Swift/UVOT Upper Limits

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