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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"

26527 results found.

  1. GRB 100713A: a long GRB detected by INTEGRAL
  2. GRB 100707A: Suzaku WAM observation of the prompt emission
  3. Konus-Wind observation of GRB 100707A
  4. GRB 100707A: Fermi GBM detection
  5. GRB 100628A: Chandra observations
  6. Tentative redshift of GRB100704A from Swift-XRT data
  7. Konus-Wind observation of GRB 100704A
  8. GRB 100704A: Swift XRT refined analysis
  9. GRB 100704: Swift/UVOT Upper Limits
  10. GRB 100704A: Fermi GBM observation
  11. GRB 100704A: Enhanced Swift-XRT position
  12. GRB 100704A: Swift detection of a burst
  13. GRB 100615A: Additional Gemini/NIRI observations
  14. GRB 100526A: Gemini/NIRI afterglow confirmation and host galaxy
  15. GRB 100702A: Swift XRT refined analysis
  16. Swift/UVOT observations of GRB100702A
  17. GRB 100701B: Fermi GBM detection
  18. GRB 100702A: Magellan near-IR observations
  19. GRB 100702A: VLT optical observations
  20. GRB 100702: ROTSE-III Optical Limits
  21. GRB 100702A: Swift detection of a short burst
  22. GRB 100615A: Chandra X-ray ToO Observation
  23. GRB 100213B: Detection of Fading Optical Afterglow
  24. GRB 100625A: Fermi GBM detection
  25. GRB 100628A: GROND optical/NIR observations of the host candidate
  26. GRB 100628A: Gemini North Observations
  27. GRB100625A: GROND confirmation of constant source
  28. GRB 090709A: Host galaxy detection
  29. GRB 100628A: Swift/UVOT Upper Limits
  30. GRB100628A: RTT150 optical observations
  31. GRB 100628A: Swift detection of a short hard burst
  32. GRB 100614A: CrAO optical limit
  33. GRB 100625A: Swift/UVOT Upper Limits
  34. Konus-Wind observation of GRB 100625A
  35. GRB 100625A: Swift-XRT Team refined analysis
  36. GRB 100625A: Enhanced Swift-XRT position
  37. GRB 100625A: Swift detection of a short hard burst
  38. GRB 100418A: late time optical observations
  39. Konus-Wind observation of GRB 100621A
  40. GRB 100621A: IRSF/SIRIUS NIR Observation
  41. GRB 100621A: Swift/UVOT observations
  42. GRB 100621A: Swift XRT refined analysis
  43. GRB 100621A: GROND observation of bright NIR afterglow
  44. GRB 100621A: Enhanced Swift-XRT position
  45. GRB 100621A: ROTSE-III Optical Limits
  46. GRB 100621A: Swift detection of a burst
  47. GRB 100606A: Optical Limits
  48. GRB 100619A: Fermi GBM detection
  49. GRB 100619A: Swift/UVOT Upper Limits
  50. GRB 100619A: Swift-XRT refind analysis
  51. GRB 100619A: Enhanced Swift-XRT position
  52. GRB 100619A: Swift detection of a burst
  53. GRB 100614A: Gemini/NIRI Observations
  54. GRB 100615A: Gemini/NIRI Observations
  55. GRB 100615A: Swift/UVOT Upper Limits
  56. GRB 100614A: Swift/UVOT Upper Limits
  57. GRB 100614A: NOT optical upper limits
  58. GRB 100615A: Fermi GBM detection
  59. GRB 100615A: Swift-BAT refined analysis
  60. GRB 100614A: Enhanced Swift-XRT position
  61. GRB 100615A: Enhanced Swift-XRT position
  62. GRB 100615A: Swift-XRT refined analysis
  63. GRB 100614A: Swift-XRT refined analysis
  64. GRB 100615A: GROND observations, upper limits
  65. GRB 100615A: PAIRITEL NIR Upper Limits
  66. GRB 100615A: NTT/Ultracam imaging
  67. GRB 100615A: Swift detection of a burst
  68. GRB 100614A: BOOTES-2/TELMA optical observations
  69. GRB 100614A: Liverpool Telescope Observations
  70. GRB 100614A: Swift detection of a burst
  71. GRB 100606A: Suzaku WAM observation of the prompt emission
  72. GRB 100606A: GROND observations
  73. Trigger 424161: Swift/BAT trigger on XTE J1946+274/GRO J1944+26
  74. Konus-Wind observation of GRB 100606A
  75. Radio detection of GRB100418a with ATCA
  76. GRB 100606A: Swift/UVOT Upper Limits
  77. GRB 100606A Swift-XRT refined analysis
  78. GRB 100606A: Enhanced Swift-XRT position
  79. Swift Trigger 424040 is not a GRB
  80. GRB 100606A: Swift detection of a burst
  81. Swift detection of outburst from the SFXT IGR J18410-0535
  82. GRB 100111A: Maidanak optical observations
  83. GRB 100418A: Maidanak optical observations
  84. GRB 100513A: CrAO optical observations
  85. GRB 100514A: CrAO optical observations
  86. GRB 100526A: optical upper limit
  87. Konus-Wind observation of GRB 100528A
  88. GRB 100528A: Faulkes Telescope North Detection
  89. GRB 100528A: GROND detection in all bands
  90. GRB 100528A: NOT optical observation
  91. Swift UVOT and UVOT-enhanced XRT position for GRB 100528A
  92. GRB100526B: GROND Upper limits
  93. GRB 100528A: Fermi GBM observation
  94. GRB 100528A: SuperAGILE Localization of a Long GRB
  95. GRB 100526B: Swift-XRT confirmation of fading afterglow
  96. GRB 100526B: Swift/UVOT Upper Limits
  97. GRB 100526A: Swift/UVOT Upper Limits
  98. GRB 100526A: Gemini/NIRI infrared afterglow candidate
  99. GRB 100526A: NOT optical upper limit
  100. GRB 100526A: Swift XRT refined analysis

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