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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

28198 results found.

  1. INT+WFC observations of GRB 061126
  2. GRB 061126: Possible Jet Break
  3. GRB 061121: Second Epoch ATCA Radio Observations
  4. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  5. Swift XRT on-board boresight update
  6. GRB 061121: ATCA & WSRT Radio Observations
  7. GRB061121: optical observations
  8. GRB 061126: Early Super-LOTIS Observations
  9. GRB 061126: optical observation
  10. GRB 061126: Tautenburg afterglow observations
  11. GRB061126: Optical afterglow observations from MIRO
  12. GRB061126: Optical afterglow observations from MIRO
  13. GRB 061126: Swift-XRT refined analysis
  14. GRB 061126: Swift/UVOT Observations
  15. GRB 061126: Early Detection of the IR Afterglow
  16. GRB 061126: Faulkes Telescope North Optical Observations
  17. GRB 061126: Swift/UVOT Afterglow Detection
  18. GRB 061126: XRT position
  19. GRB 061126: Swift detection of a burst
  20. GRB 061122: Confirmation of X-ray/Optical Afterglow
  21. GRB061121: optical observations
  22. GRB 061122: Candidate Optical Afterglow
  23. GRB 061121: Ep,i - Eiso correlation
  24. GRB 061121: MDM Optical Decay
  25. GRB061122: Swift/UVOT Optical Observations
  26. GRB 061121: ART detection in Ic
  27. GRB061121: P60 Observations
  28. Radio detection of GRB 061121
  29. GRB061122: Swift-XRT position
  30. GRB 061121 declared "Burst of Interest" by Swift team
  31. Swift-BAT trigger 239987 is not a GRB
  32. GRB 061121: Swift/UVOT Observations
  33. GRB 061121: Swift-XRT Team Refined Analysis
  34. GRB 061121: Optical observation at the KANATA 1.5m telescope
  35. GRB 061121: Faulkes Telescope North Optical Observation
  36. GRB061121: Spectroscopic Redshift
  37. GRB061121: Keck spectroscopic observations
  38. GRB 061121: Swift detection of a bright burst with an optical counterpart
  39. GRB 060605: NIR Observations
  40. GRB 050915B: optical afterglow
  41. GRB 060111B: Swift UVOT Refined Magnitudes
  42. GRB 061110A: refined R-band analysis
  43. GRB 061110B: NIR Observations
  44. Swift TOO observations of GRB061110A
  45. Swift/UVOT Upper Limits for GRB061110b
  46. Swift/UVOT Upper Limits for GRB061110a
  47. GRB 061110A - VLT tentative redshift
  48. GRB 061110B: Swift XRT refined analysis
  49. GRB 061110B: VLT redshift
  50. GRB 061110A: Swift XRT refined analysis
  51. GRB 061110B: Swift/XRT position
  52. GRB 061110B : Liverpool Telescope Optical Afterglow Detection
  53. GRB 061110B: Swift-UVOT Initial Observation
  54. GRB 061110B: Swift detection of a burst
  55. GRB 061110: NOT observations
  56. GRB 061110: Candidate confirmed
  57. GRB 061110 : Optical afterglow candidate
  58. GRB 061110: ROTSE-III Optical Limits
  59. GRB 061110: Swift detection of a burst
  60. GRB061110A - Optical Non-detection
  61. GRB 061109: Swift detection of a possible burst
  62. GRB061028: MAGIC telescope GeV observation
  63. GRB 061007: Third Epoch ATCA Radio Observations
  64. GRB061019: second epoch CrAO observations
  65. GRB 061028: Swift/XRT Astrometry Correction
  66. GRB 061102: Swift/UVOT Magnitude Upper Limits
  67. GRB 061102, XRT refined analysis
  68. GRB 061004: Further VLT/NTT observations
  69. GRB 061028: Optical R passband observations
  70. GRB 061102B: Swift detection of a possible burst
  71. GRB 061102: Swift detection of a burst
  72. GRB 061028: VLA Observation
  73. GRB 061004: Swift/XRT Astrometry Correction
  74. GRB 060801: Swift/XRT Astrometry Correction
  75. GRB 061028: Futher P200 Observations
  76. GRB 061028: MDM Observations
  77. GRB 061028: P200 Observations
  78. GRB 061028: SARA upper limit
  79. GRB 061028: z band imaging
  80. GRB061028: XRT refined analysis
  81. GRB 061028: Swift/UVOT Observations
  82. GRB 061028: TAROT Calern observatory late optical observations
  83. GRB 061028: Swift detection of a burst
  84. GRB 061027, Swift refined analysis of a possible burst
  85. GRB 061027: Swift detection of a possible burst
  86. GRB061025: ROTSE-III Confirmation of Optical Counterpart
  87. GRB061025: Swift XRT refined analysis
  88. GRB061025: Swift/UVOT observations
  89. GRB 061019: MITSuME upper limits
  90. GRB 061025: REM observations
  91. GRB 061025: Gemini-S observations
  92. GRB061025: Swift XRT position
  93. Swift XRT boresight update
  94. GRB 061021: Swift-XRT refined analysis
  95. GRB 061021: Swift detection of a burst
  96. GRB 061019: Super-LOTIS upper limit
  97. GRB060904b: optical observations
  98. GRB061019: optical observations
  99. GRB061019: optical observations
  100. GRB 061019: dust-scattered X-ray halo detected in Swift/XRT

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