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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"

28057 results found.

  1. GRB070612A: MITSuME Okayama Observation
  2. GRB 070612A: continued SARA observations
  3. GRB 070611: Watcher Observations
  4. Swift Trigger 282176 is Cygnus X-1
  5. GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
  6. GRB 070612B: SARA upper limit
  7. GRB 070612B, Swift-BAT refined analysis
  8. GRB 070612A, Swift-BAT refined analysis
  9. SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
  10. GRB 070612B: Swift/UVOT upper limits
  11. GRB 070612B: FRAM limit
  12. GRB070612B: P60 Observations
  13. GRB 070612A: SARA detection of possible OT
  14. GRB 070610: TAROT Calern observatory optical observations
  15. GRB 070610: MITSuME OAO optical upper limit
  16. GRB070612 - SDSS Pre-Burst Observations
  17. GRB 070612: Swift detection of a burst
  18. GRB 070610: OPTIMA-Burst detection of continued strong flaring activity
  19. GRB 070610: SARA upper limit
  20. GRB 070610: Swift-XRT refined analysis
  21. GRB 070611: Swift/UVOT Observations
  22. GRB 070611: Swift-XRT refined analysis
  23. GRB 070611, Swift-BAT refined analysis
  24. GRB 070610: Optical observations from OSN
  25. GRB 070610: Watcher Observations
  26. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  27. GRB 070611: ROTSE-III Optical Limits
  28. GRB 070610: Swift-UVOT Upper Limits
  29. GRB 070610: OPTIMA-Burst high-time-resolution optical observations
  30. GRB 070610, Swift-BAT refined analysis
  31. GRB 070412: TAROT Calern observatory optical observations
  32. GRB 070411: TAROT Calern observatory optical observations
  33. GRB070520B: optical observations
  34. GRB070520: optical observation
  35. GRB070518: optical observation
  36. GRB070521: optical observation
  37. GRB 070531: NOT nIR observations
  38. GRB 070531: Swift-BAT refined analysis
  39. GRB 070531: I-band observations from IAC80
  40. GRB 070531: Liverpool Telescope Optical Observations
  41. GRB 070529: SARA upper limit
  42. Swift/UVOT refined analysis of GRB070529
  43. GRB 070529: Optical aterglow from MIRO
  44. GRB 070529: Swift-XRT refined analysis
  45. GRB 070529, Swift-BAT refined analysis
  46. GRB 070529: Xinglong TNT Optical Upper Limit
  47. GRB 070529: Swift detection of a burst with an optical aterglow
  48. GRB 070412: Deep Keck imaging
  49. Swift trigger 280447 is probably a Galactic transient
  50. GRB 070518, deep LBT photometry
  51. Konus-Wind observation of GRB 070521
  52. GRB070521: Second Epoch Gemini Imaging
  53. GRB 070521: Swift/UVOT Upper Limits
  54. GRB 070521, optical observation
  55. GRB 070521: Swift-XRT refined analysis
  56. GRB 070521: Keck imaging
  57. GRB070521: Gemini Observations
  58. GROND upper limits of GRB 070521
  59. GRB 070520B: SARA upper limit
  60. GRB 070520A: SARA upper limit
  61. GRB 070521: SARA upper limit
  62. GRB 070521: Subaru observations and possible host detection
  63. GRB 070520B: Swift/UVOT Upper Limits
  64. GRB 070520A: Subaru Observations
  65. GRB 070521, Swift-BAT refined analysis
  66. GRB 070520A: Swift UVOT Upper Limits
  67. GRB 070520B: Swift-XRT refined analysis
  68. GRB 070521: TAROT La Silla observatory optical observations
  69. GRB070521 - SDSS Pre-Burst Observations
  70. GRB 070521: Swift detection of a burst
  71. GRB 070520A: MITSuME Akeno optical upper limits
  72. GRB 070520B, Swift-BAT refined analysis
  73. GRB 070520A, Swift-BAT refined analysis
  74. GRB 070520A: Swift-XRT refined analysis
  75. GRB 070518: TNG observations
  76. GRB 070520B: Swift detection of a burst
  77. GRB 070520: Xinglong EST optical Upper Limit
  78. GRB 070520: Swift detection of a burst
  79. VLA observation of GRB 070518
  80. GRB 070518: Swift-XRT refined analysis
  81. GRB070518: UVOT refined analysis
  82. GRB 070518, Swift-BAT refined analysis
  83. GRB 070518: OT confirmed form Xinglong TNT observation
  84. GRB 070518: Swift detection of a burst with optical afterglow
  85. GRB070517: Swift-XRT Refined Analysis
  86. GRB 070517, Swift-BAT refined analysis
  87. GRB 070517: Optical search
  88. GRB 070517: Swift detection of a burst
  89. GRB 070509: objects inside XRT error circle
  90. GRB 070512: IPN localization and Konus spectrum of a bright burst
  91. GRB070419A: optical observations
  92. GRB 070509: Swift/UVOT Upper Limits
  93. Konus-Wind and Konus-A observation of GRB 070508
  94. GRB 070510: Swift detection of a possible burst
  95. GRB070509: Swift-XRT Refined Analysis
  96. GRB 070509, Swift-BAT refined analysis
  97. GRB 070508: Suzaku/WAM observation of the prompt emission
  98. GRB 070509: REM observations
  99. GRB070508: Swift/UVOT Observations
  100. GRB 070508, Swift-BAT refined analysis

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