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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"

12318 results found.

  1. GRB 120907A: Swift/UVOT Detection
  2. GRB 120819A: optical upper limit
  3. GRB 120830A: Further Swift Observations
  4. GRB 120830A: Fermi GBM observation
  5. GRB 120830A: early MASTER optical limit
  6. Fermi trigger 368003226 : MASTER optical observations
  7. GRB 120819A: Swift/UVOT Upper Limits
  8. GRB 120817A: Swift/UVOT Upper Limits
  9. GRB 120821A: Swift/UVOT Upper Limits
  10. GRB 120821A: GROND upper limits
  11. GRB 120819A: MITSuME Ishigakijima upper limits
  12. GRB 120819A: MITSuME Okayama Optical upper limits
  13. GRB 120819A: MASTER optical observations
  14. GRB 120819A: Swift detection of a burst
  15. GRB 120817B: Swift-XRT observations
  16. GRB 120816A: Swift/UVOT Detection of the Optical Afterglow
  17. GRB 120815A: MASTER-ICATE observations
  18. GRB 120816A: optical upper limit
  19. GRB 120815A: Swift/UVOT Detection of the Optical Afterglow
  20. GRB 120816A: Swift detection of a burst
  21. GRB 120811A: Swift/XRT-UVOT Obseravations
  22. GRB 120811C: EVLA Observations
  23. GRB 120811C: Swift/UVOT Detection
  24. Trigger 530588: Swift detection of XMM J174457-2850.3
  25. GRB 120803A: optical upper limit
  26. GRB 120807A: Swift/UVOT Upper Limits
  27. GRB 120803A: Confirmation of the X-ray afterglow
  28. GRB 120804A: ATCA 34GHz upper limit
  29. GRB 120807A: Fermi/LAT upper limit
  30. GRB 120804A: ATCA 34GHz upper limit
  31. GRB 120805A: Swift/UVOT Upper Limits
  32. Swift trigger 530214: uncertain if real or not
  33. GRB 120802A: Swift/UVOT Upper Limits
  34. GRB120805A: Liverpool Telescope observations
  35. GRB 120804A: MITSuME Okayama Optical upper limits
  36. GRB 120804A: Swift/UVOT Upper Limits
  37. GRB 120804A: GROND upper limits
  38. GRB 120802A: EVLA Observations
  39. GRB 120803B: MITSuME Okayama Optical upper limits
  40. GRB 120803A: MITSuME Okayama Optical upper limits
  41. GRB 120803B: MITSuME Akeno Optical upper limits
  42. GRB 120803B: Swift detection of a burst
  43. GRB 120803A: Swift detection of a possible burst
  44. GRB 120802A: GRT Optical Observation
  45. GRB 120802A: MASTER optical observations
  46. GRB 120802A: optical uper limit in ISON-NM observatory
  47. GRB 120802A: Swift detection of a burst
  48. GRB 120729A: EVLA Observations
  49. GRB 120729A: Swift/UVOT Detection
  50. GRB 120729A: Xinglong TNT optical upper limit
  51. GRB 120728A: Swift/UVOT Upper Limits
  52. GRB 120728A: Swift detection of a burst
  53. Swift Trigger 528925 is probably a noise fluctuation
  54. GRB 120722A: optical upper limit
  55. GRB 120724A: Swift/UVOT Detection of the Optical Afterglow
  56. GRB 120724A: Swift detection of a burst
  57. GRB 120722A: Swift/UVOT Upper Limits
  58. GRB 120722A: Correction for GCN circ.13500
  59. GRB 120722A: Swift detection of a burst
  60. GRB 120711A: ATCA 34GHz final observations (upper limit)
  61. GRB 120714B: Swift/UVOT Detection
  62. GRB120714A: Swift/UVOT upper limits
  63. GRB 120714A: GROND upper limits
  64. GRB120714A: UVOT non-detection
  65. GRB120711B: MITSuME Ishigakijima upper limits
  66. GRB 120711A: ATCA 34GHz further observations (upper limit)
  67. GRB 120712A: Swift/UVOT Detection
  68. GRB 120711A: ATCA 34GHz upper limit
  69. GRB 120711B: Swift/UVOT Upper Limits
  70. GRB 120711A: Swift/UVOT Observations
  71. GRB 120709A: Swift/UVOT Observations
  72. Swift detection of GRB 120711B or a new Galactic transient
  73. GRB 120703A: Swift/UVOT Detection
  74. GRB 120701A: Swift/UVOT Detection
  75. Swift Trigger 525554 is noise
  76. GRB 120630A: Swift-BAT/-XRT/-UVOT refined analysis
  77. GRB 120624B: Swift/UVOT Upper Limits
  78. Watcher follow-up observations of IGR J17062-6143 (Swift trigger 525148)
  79. GRB 120624B: GROND upper limits
  80. XRF 120626B: MAXI/GSC detection
  81. Swift detection of Ginga 0834-430
  82. GRB 120624B: NOT optical upper limit
  83. Swift Trigger 524949: Noise fluctuation near a galaxy
  84. GRB 120622A: MAXI/GSC detection
  85. Swift triggers (#524542) on a Galactic source
  86. GRB 120614A: MAXI/GSC detection of a burst
  87. GRB 120612A: BOOTES-3 optical upper limit
  88. GRB 120612A: Swift detection of a burst
  89. GRB 120528C: MAXI/GSC detection
  90. GRB120521B: SSO 2.3m upper limits
  91. GRB 120521A: ATCA 34GHz upper limit
  92. GRB 120521C: EVLA 22 GHz Upper Limit
  93. GRB 120521A: GROND Upper limits
  94. GRB 120521C: Swift/UVOT Upper Limits
  95. GRB 120521B: Swift/UVOT Upper Limits
  96. GRB 120521C: MASTER optical limit
  97. GRB 120521B: GROND Upper limits
  98. GRB 120521C: PAIRITEL NIR Upper Limits
  99. GRB120521C: Liverpool Telescope observations
  100. GRB 120521C: Swift detection of a burst

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