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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"

19605 results found.

  1. GRB 230618A: Swift-XRT refined Analysis
  2. GRB 230616A: Swift-XRT observations
  3. GRB 230618A: KAIT Optical Observations
  4. Swift GRB 230618A: Global MASTER-Net observations report
  5. GRB230618A: LCOGT Optical Observations
  6. GRB 230618A: Prompt enhanced Swift-XRT position
  7. GRB 230618A: Swift detection of a burst
  8. GRB 230616A: Swift ToO observations
  9. GRB 230616A: AstroSat CZTI detection
  10. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  11. GRB 230614B: Fermi GBM Observation
  12. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  13. GRB 230606A: LCOGT Optical Observations
  14. GRB 230606A: Swift-BAT refined analysis
  15. GRB 230606A: Gaoyazi/GOT optical upper limit
  16. GRB 230606A: Fermi GBM Observation
  17. GRB 230606A: BOOTES-5/JGT optical upper limit
  18. GRB 230606A: Swift-XRT refined Analysis
  19. GRB 230606A: Swift/UVOT Upper Limits
  20. GRB 230606A: Enhanced Swift-XRT position
  21. GRB 230606A: Swift detection of a burst
  22. GRB 230510A: Swift-BAT refined analysis
  23. GRB 230523B: GRBAlpha detection
  24. GRB 230523B: Name correction from GCN Circular 33859
  25. GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
  26. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
  27. IPN triangulation of GRB 230518A (short)
  28. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
  29. GRB 230518A: Fermi GBM Observation
  30. GRB 230518A: Swift/BAT-GUANO detection
  31. LIGO/Virgo S230518h: Swift XRT observations, 8 X-ray sources
  32. Improved IPN triangulation of GRB 230512A
  33. IPN triangulation of GRB 230512A
  34. GRB 230510A: GRBAlpha detection
  35. GRB 230512A: Swift-XRT observations
  36. GRB 230512A: Tiled Swift observations
  37. GRB 230512A: Fermi-LAT detection
  38. GRB 230510A: GIT optical upper limits
  39. GRB 230510A: LCOGT Optical Upper Limit
  40. GRB 230510A: Swift/UVOT Observations
  41. GRB 230510A: Fermi GBM detection
  42. GRB 230510A: Gaoyazi/GOT optical upper limit
  43. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  44. GRB 230510A: Nanshan/NEXT optical afterglow detection
  45. GRB 230506B: Fermi GBM detection
  46. GRB 230510A: Swift-XRT refined Analysis
  47. GRB 230510A: Enhanced Swift-XRT position
  48. GRB 230506C: Fermi GBM detection
  49. GRB 230510A: Swift detection of a burst
  50. GRB 230506B: Swift/UVOT further analysis
  51. GRB 230506C: Swift-XRT refined Analysis
  52. GRB 230506C: Swift-BAT refined analysis
  53. GRB 230506B: Swift-BAT refined analysis
  54. GRB 230506B: LCOGT Optical Upper Limits
  55. GRB 230506C: Swift/UVOT Upper Limits
  56. GRB 230506B: Swift-XRT refined Analysis
  57. GRB 230506C: Swift-XRT analysis
  58. GRB 230506C: Candidate afterglow observation by D50
  59. GRB 230506C: TSHAO possible afterglow candidate
  60. GRB 230506B: Swift/UVOT Detection
  61. GRB 230506C: Swift detection of a burst
  62. Swift GRB230506.71: Global MASTER-Net observations report
  63. GRB 230506B: Swift detection of a burst
  64. GRB 230506B: MASTER optical observations
  65. GRB 230506B: Swift detection of a burst
  66. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  67. GRB 230427A: Swift-BAT refined analysis
  68. GRB 230420A: AROMA-N Optical Upper Limit
  69. GRB 230427A: NOT optical upper limit
  70. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  71. GRB 230427A: Swift/UVOT Detection
  72. GRB 230427A: Gaoyazi/GOT optical upper limit
  73. GRB 230427A: Nanshan/HMT optical upper limit
  74. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  75. GRB 230427A: Swift-XRT refined Analysis
  76. GRB 230427A: GIT optical upper limit
  77. GRB 230427A: Bassano Bresciano Observatory upper limit
  78. GRB 230427A: BOOTES-5/JGT afterglow detection
  79. GRB 230423A(trigger #1165354): Swift-BAT refined analysis
  80. GRB 230427A: AKO Upper Limit
  81. Swift GRB230427.44: Global MASTER-Net observations report
  82. GRB 230427A: MITSuME Akeno optical upper limits
  83. GRB 230427A: Enhanced Swift-XRT position
  84. GRB 230427A: Swift detection of a burst with an optical counterpart
  85. GRB 230423A: Swift/UVOT Upper Limits
  86. GRB 230423A: Swift-XRT refined Analysis
  87. GRB 230423A: Swift-XRT afterglow detection
  88. Swift Trigger 1165354 is probably not a GRB
  89. GRB 230421A: Fermi GBM observation
  90. Konus-Wind detection of GRB 230418A
  91. GRB 230420A: Swift/UVOT Upper Limits
  92. GRB 230421: Swift/BAT-GUANO arcminute localization
  93. GRB 230420A: Swift-BAT refined analysis
  94. GRB 230420A: Swift-XRT refined Analysis
  95. GRB 230420A: MITSuME Akeno optical observation
  96. GRB 230420A: NOT optical afterglow confirmation
  97. GRB 230420A: Gaoyazi/GOT optical upper limit
  98. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  99. GRB 230420A: LCOGT Optical Upper Limit
  100. GRB 230420A: Enhanced Swift-XRT position

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