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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').

17956 results found.

  1. GRB 070110 declared a "Burst of Interest" by Swift team
  2. Further Retractions of previous Swift-BAT triggers
  3. Swift-BAT Trigger 255685 is not a GRB
  4. Trigger 255685: Swift detection of a possible burst
  5. GRB 070110: UVOT Observations of a Candidate Afterglow
  6. GRB070110: Swift XRT Team refined analysis
  7. GRB 070110, Swift-BAT refined analysis
  8. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  9. GRB 070110: Swift detection of a burst with a possible optical afterglow
  10. GRB070107: Swift/XRT refined analysis
  11. GRB 070107: Possible UVOT Afterglow
  12. GRB 070107, Swift-BAT refined analysis
  13. GRB 070107: Swift/XRT position
  14. GRB 070107: Swift detection of a burst
  15. GRB070103: APO SPIcam i' and z' limits
  16. GRB 070103: Swift/UVOT Upper limits
  17. GRB070103: Swift XRT refined analysis
  18. GRB 070103, Swift-BAT refined analysis
  19. GRB 070103: TAROT Calern observatory optical observations
  20. GRB 070103: Swift detection of a burst
  21. Retractions of previous Swift-BAT triggers
  22. Konus-Wind observation of GRB 061222A
  23. GRB 061210: Swift/XRT Astrometry Correction
  24. GRB 050826: MDM Redshift
  25. GRB 061222B, Swift-BAT refined analysis
  26. GRB061222A Swift/UVOT: Upper Limits
  27. GRB 061222B: Swift/UVOT Upper limits
  28. GRB061222B: Swift-XRT Refined Analysis
  29. GRB 061222B: BOOTES-IR optical observations
  30. GRB 061222B: SARA upper limit
  31. GRB 061222A: Swift-XRT refined analysis
  32. GRB 061222A, Swift-BAT refined analysis
  33. GRB 061222B: TAROT La Silla observatory optical observations
  34. GRB 061222B: Swift detection of a burst
  35. GRB 061222A: Prompt ROTSE-III Optical Limits
  36. GRB 061222: Swift detection of a burst
  37. GRB 061217: Astrometry-Corrected XRT Position
  38. GRB 061217, Candidate host galaxy
  39. GRB 061217 - Swift/XRT position correction
  40. GRB 061218: TAROT La Silla observatory optical observations
  41. GRB 061217: TAROT Calern observatory optical observations
  42. GRB 061218, Swift-BAT refined analysis
  43. Swift triggers (#251863) on a possible burst
  44. GRB061217: Swift/UVOT refined analysis.
  45. GRB 061217: optical observations at Calar Alto
  46. GRB061217 - Swift/XRT refined analysis
  47. GRB 061217, Further Swift-BAT refined analysis of the short hard burst
  48. GRB 061217, Swift-BAT refined analysis
  49. GRB 061217: ROTSE-III Optical Limits
  50. GRB 061217: Swift detection of a short hard burst
  51. GRB 061210: MDM Follow-up Observation
  52. GRB061210: Swift/UVOT observations
  53. Swift-BAT Trigger 250908 is a Cosmic Ray Shower event
  54. GRB 061210: Swift XRT analysis - Possible counterparts
  55. GRB 061210 : Faulkes North Telescope optical limit
  56. GRB 061214(?): ROTSE-III Optical Limits
  57. GRB 061214(?): Swift detection of a possible burst
  58. Swift/BAT trigger #250033 is due to a known source during loss of
  59. GRB 061213: MASTER-VWF-Kislovodsk optical candidate
  60. GRB 061213: MASTER-VWF-Kislovodsk observations
  61. GRB 061210: MDM Observation
  62. GRB 061210, Swift-BAT refined analysis of the SHB
  63. GRB 061210: Swift-BAT detection of a short burst
  64. Optical Afterglow observations of GRB 061126
  65. GRB061126: update on the Swift-XRT afterglow light curve
  66. Corrections for Swift/UVOT Exposure Times for GRBs 061110B and 061121
  67. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  68. GRB061126 : NMSU 1.0m observations
  69. GRB 061202: Swift XRT refined analysis
  70. GRB061202: FRAM early follow-up limit
  71. GRB061202 optical limit by "Pi of the Sky"
  72. Konus-Wind observation of GRB 061201
  73. GRB061202: Swift/UVOT Upper Limits
  74. GRB 061202, Swift-BAT refined analysis
  75. GRB 061202: Swift detection of a burst
  76. GRB 061201: Swift XRT Team refined analysis
  77. GRB 061201: Initial UVOT Observations
  78. GRB 061201, Swift-BAT refined analysis of the SHB
  79. GRB 061201: Swift detection of a short hard burst
  80. GRB 061201: Coincidence with a Galaxy Cluster
  81. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  82. Swift XRT on-board boresight update
  83. GRB 061126: Early Super-LOTIS Observations
  84. GRB061126: Optical afterglow observations from MIRO
  85. GRB061126: Optical afterglow observations from MIRO
  86. GRB 061126: Swift-XRT refined analysis
  87. GRB 061126: Swift/UVOT Observations
  88. GRB 061126, Swift-BAT refined analysis
  89. GRB 061126: Faulkes Telescope North Optical Observations
  90. GRB 061126: Swift/UVOT Afterglow Detection
  91. GRB 061126: XRT position
  92. GRB 061126: Swift detection of a burst
  93. GRB 061122: Confirmation of X-ray/Optical Afterglow
  94. GRB 061122: Candidate Optical Afterglow
  95. GRB 061121: Ep,i - Eiso correlation
  96. GRB061122: Swift/UVOT Optical Observations
  97. GRB061122: Swift-XRT position
  98. GRB 061121 declared "Burst of Interest" by Swift team
  99. Konus-Wind and Konus-A observations of GRB 061121
  100. Swift-BAT trigger 239987 is not a GRB

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