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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"

24038 results found.

  1. GRB 100805A: ROTSE-III Optical Limits
  2. GRB 100805A: Swift detection of a burst with an optical counterpart
  3. GRB 100802A: Fermi GBM observation
  4. GRB 100802A: NOT optical observation
  5. GRB 100802A: P60 Observations
  6. GRB 100802A: XRT refined analysis
  7. GRB 100802A: Swift/UVOT Possible Optical Afterglow
  8. GRB 100728A: Suzaku WAM observation of the prompt emission
  9. GRB 100802A: Swift-BAT refined analysis
  10. GRB 100802A: Liverpool Telescope observations
  11. GRB 100802A: ROTSE-III Optical Limits
  12. GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow
  13. GRB 100802A: Swift detection of a burst
  14. GRB 100728B - NOT optical observation
  15. GRB 100728B: Swift/UVOT Observations
  16. GRB 100728B: Lick Observations
  17. GRB 100728B: Continued KAIT observations
  18. GRB 100728B, Swift-BAT refined analysis
  19. GRB 100728B: Swift-XRT Refined Analysis
  20. Konus-Wind observation of GRB 100728A
  21. GRB 100728A: GROND Detection of the NIR Afterglow Candidate
  22. GRB 100727A: Swift/UVOT Upper Limits
  23. GRB 100728A, Swift-BAT refined analysis
  24. GRB 100728A: Swift/UVOT Upper Limits
  25. GRB 100728B: Fermi GBM observation
  26. GRB 100728A: Swift-XRT refined analysis
  27. GRB 100728B: GROND Detection of the NIR Afterglow
  28. GRB 100728B: Skynet/PROMPT Detections (correction)
  29. GRB 100728B: KAIT optical afterglow detection (correction)
  30. GRB 100728B: Swift detection of a burst with an optical counterpart
  31. GRB 100728A: Skynet/PROMPT Detections
  32. GRB 100728A: KAIT optical afterglow detection
  33. GRB 100728A: Fermi GBM observation
  34. GRB 100728A: Swift detection of a burst
  35. GRB 100727A: Swift XRT refined analysis
  36. GRB 100727A: Fermi GBM observation
  37. GRB 100727A, Swift-BAT refined analysis
  38. GRB 100727A: Swift detection of a burst
  39. GRB 100724B: Suzaku WAM observation of the prompt emission
  40. GRB 100725B: Swift-BAT refined analysis
  41. GRB 100725B: refined XRT analysis
  42. GRB 100725A: GROND upper limits
  43. GRB 100725B: Swift/UVOT Upper Limits
  44. GRB 100725A: Swift/UVOT Upper Limits
  45. GRB 100725A: Swift-BAT refined analysis
  46. GRB 100725A: Swift XRT refined analysis
  47. GRB100725B: Faulkes Telescope North observations
  48. GRB 100725B: Swift detection of a burst
  49. GRB100725A Faulkes Telescope South observations
  50. Konus-Wind observation of GRB 100724B
  51. GRB 100725A: Swift detection of a burst
  52. GRB 100724B: Fermi LAT and GBM analysis
  53. GRB 100724B: Fermi GBM detection
  54. GRB 100724A: Swift/BAT spectral lag results
  55. GRB 100724A: Swift XRT refined analysis
  56. GRB 100724A: Swift/UVOT observations
  57. GRB 100724A: Swift-BAT refined analysis
  58. GRB 100724A, GROND detection of an afterglow candidate
  59. GRB 100724A: Swift detection of a burst
  60. GRB 100614A: 10.4-m GTC deep-optical limit
  61. GRB 100722A: Fermi GBM detection
  62. GRB 100718A: MASTER-Net optical prompt and alert observations
  63. GRB 100719A: Swift-BAT refined analysis
  64. GRB 100719A: Swift detection of a burst
  65. GRB 100713A: Swift XRT refined analysis
  66. Fermi GBM trigger 300794561 (100714419) is not a GRB
  67. GRB100713A: Swift/UVOT observations
  68. GRB 100713A: GROND upper limits
  69. GRB100713A: Swift X-ray afterglow detection
  70. GRB 100707A: Suzaku WAM observation of the prompt emission
  71. Fermi GBM trigger 300370702 (100709513) is not a GRB
  72. Konus-Wind observation of GRB 100707A
  73. GRB 100707A: Fermi GBM detection
  74. Tentative redshift of GRB100704A from Swift-XRT data
  75. Konus-Wind observation of GRB 100704A
  76. GRB 100703A: a short GRB detected by INTEGRAL
  77. GRB 100704A: Swift XRT refined analysis
  78. GRB 100704: Swift/UVOT Upper Limits
  79. GRB 100704A: Fermi GBM observation
  80. GRB 100704A: Swift-BAT refined analysis
  81. GRB 100704A: Swift detection of a burst
  82. GRB 100702A, Swift-BAT refined analysis
  83. Fermi GBM trigger 299767472 (100702531) is not a GRB
  84. GRB 100702A: Swift XRT refined analysis
  85. Swift/UVOT observations of GRB100702A
  86. GRB 100701B: Fermi GBM detection
  87. GRB 100702: ROTSE-III Optical Limits
  88. GRB 100702A: Swift detection of a short burst
  89. GRB 100625A: Fermi GBM detection
  90. GRB 100628A: GROND optical/NIR observations of the host candidate
  91. GRB 100628A: Gemini North Observations
  92. GRB 100628A: Swift XRT refined position
  93. GRB100625A: GROND confirmation of constant source
  94. GRB 100628A: Swift/UVOT Upper Limits
  95. GRB 100628A: Swift XRT detection of a possible X-ray afterglow
  96. GRB 100628A: INTEGRAL SPI-ACS light curve
  97. GRB 100628A: Swift-BAT refined analysis
  98. GRB 100628A: Swift detection of a short hard burst
  99. Swift-BAT trigger 426048 is not a burst
  100. GRB 100625A: Swift/UVOT Upper Limits

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