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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"

25029 results found.

  1. GRB 060708: Refined analysis of the Swift-BAT burst
  2. GCN 060707: Swift-UVOT observations
  3. GRB 060707: Swift-XRT refined analysis
  4. GRB 060708: Swift detection of a burst with an UVOT countpart
  5. GRB 060707: Refined analysis of the Swift-BAT burst
  6. GRB 060707: BOOTES-IR optical observation
  7. GRB 060515: Upper Limit on Host Galaxy
  8. GRB 060614: SMARTS host galaxy observations
  9. GRB 060614: Detection of a Possible, Late-Time Rebrightening
  10. GRB 060109: Upper Limit on Host Galaxy
  11. GRB 060105: Upper limit on Host Galaxy
  12. GRB 060614: Redshift
  13. Trigger 215279: Swift detection of a possible burst (GRB 060619)
  14. GRB050326: Host Galaxy Candidates
  15. GRB050124: Possible Host Galaxy
  16. GRB050223: Host Galaxy
  17. Konus-Wind observation of GRB 060614
  18. GRB060605: optical observation
  19. GRB 060614: optical observations
  20. GRB 060605, optical observations
  21. GRB 060614: Swift-BAT refined analysis
  22. GRB 060614: Swift/UVOT Observations
  23. GRB060614: Swift-XRT refined analysis
  24. GRB 060614: Swift detection of a burst with a bright optical and X-ray counterpart
  25. GRB 060602A: Swift/XRT analysis
  26. BAT Trigger #214277 is SGR 1900+14
  27. GRB 060610: KAIT observations
  28. GRB 060607: RTT150 optical observations
  29. GRB 060607B: Swift-BAT Refined Analysis
  30. GRB060602A: Swift/UVOT upper limits
  31. GRB 060607B: Swift detection of a burst
  32. GCN 060607: Swift-UVOT obswervations.
  33. GRB 060607: Swift-BAT Refined Analysis
  34. GRB 060607: Swift-XRT Team refined analysis
  35. GRB 060607: IR observations
  36. GRB 060502B: A Bright Early-type Galaxy as Putative Host of the Short Burst
  37. GRB 060605: RTT150 optical observations
  38. GRB 060607: REM NIR afterglow
  39. GRB 060607: Swift detection of a burst with bright optical counterpart
  40. GRB 060522: PROMPT Optical Limits
  41. GRB 060605 BAT refined analysis
  42. GRB 060605: Xinglong TNT optical observations
  43. GRB060602B : REM infrared observations
  44. GRB060605: Swift/UVOT detections
  45. GRB 060605: Swift-XRT Team refined analysis
  46. GRB 060605: RTT150 optical observations
  47. GRB 060605: Swift detection of a burst with optical counterpart
  48. GRB060604: Swift/UVOT detections
  49. GRB 060604: Swift-XRT Team refined analysis
  50. GRB 060604: BAT refined analysis
  51. GRB 060604A: ROTSE-III Optical Limits
  52. GRB 060604: Swift detection of a burst with possible optical counterpart
  53. GRB 060602A: Swift-BAT Refined Analysis: Correction
  54. GRB 060602B: Swift-XRT Refined Analysis
  55. GRB 060602B: Swift-BAT Refined Analysis
  56. GRB 060602B: Swift/UVOT observations
  57. GRB 060602A: Swift-BAT Refined Analysis
  58. GRB 060211A : WIDGET simultaneous optical observations
  59. GRB060602A: optical observations(/transient?)
  60. GRB 060602B: Swift detection of a burst
  61. GRB060602B: BOOTES-IR candidate afterglow
  62. GRB060602 - SDSS Pre-Burst Observations
  63. GRB 060502A: Optical afterglow observations
  64. GRB 060526: Break in X-ray light curve
  65. GRB060526, optical observations
  66. GRB 051227 : WIDGET simultaneous optical observations
  67. GRB 051028 : WIDGET pre-trigger limit
  68. GRB060526: Optical counterpart from MIRO
  69. GRB 060526: RTT150 optical observations
  70. GRB060526: optical observations
  71. GRB 060526: REM observations
  72. GRB 060526: RTT150 optical observations, afterglow flattening
  73. GRB 060526: MDM-2.4m Observations
  74. GRB 060526: Refined analysis of the Swift-BAT burst
  75. GRB 060526: RTT150 optical observations
  76. GRB060526, optical observations
  77. GRB 060526: Swift/XRT Team refined analysis
  78. GRB 060526: ROTSE-III Observations of Optical Counterpart
  79. GRB 060526: Watcher Observations
  80. GRB060526 - SDSS Pre-burst Observations
  81. GRB 060526: Swift detection of a burst with x-ray and optical afterglow
  82. GRB 060413 : WIDGET simultaneous optical observations
  83. XMM-Newton observation of GRB060510b
  84. GRB060512: Late-Time P200 Observations
  85. GRB 060522: Swift-BAT Refined Analysis
  86. GRB 060522: REM NIR observations
  87. GRB 060522: TNG optical observations
  88. GRB 060515: NIR observation
  89. GRB 060210: Jet Break in the XRT light curve
  90. GRB 060516: Refined analysis of the Swift-BAT burst
  91. GRB060515: P200 NIR Observations
  92. GRB 060505 BAT refined analysis
  93. GRB 060515 BAT refined analysis
  94. GRB 060512: TAROT optical observation
  95. GRB 060515: Swift/XRT Team refined analysis
  96. GRB 060515: Swift/UVOT Upper Limits
  97. GRB 060515: Swift/XRT position
  98. GRB 060515: Super-LOTIS Observations
  99. GRB 060515: TAROT optical observation
  100. GRB 060512: Subaru NIR observation

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