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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"

20008 results found.

  1. GRB 230606A: Enhanced Swift-XRT position
  2. GRB 230606A: Swift detection of a burst
  3. GRB 230510A: Swift-BAT refined analysis
  4. GRB 230523B: GRBAlpha detection
  5. GRB 230523B: Name correction from GCN Circular 33859
  6. GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
  7. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
  8. IPN triangulation of GRB 230518A (short)
  9. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
  10. GRB 230518A: Fermi GBM Observation
  11. GRB 230518A: Swift/BAT-GUANO detection
  12. LIGO/Virgo S230518h: Swift XRT observations, 8 X-ray sources
  13. Improved IPN triangulation of GRB 230512A
  14. IPN triangulation of GRB 230512A
  15. GRB 230510A: GRBAlpha detection
  16. GRB 230512A: Swift-XRT observations
  17. GRB 230512A: Tiled Swift observations
  18. GRB 230512A: Fermi-LAT detection
  19. GRB 230510A: GIT optical upper limits
  20. GRB 230510A: LCOGT Optical Upper Limit
  21. GRB 230510A: Swift/UVOT Observations
  22. GRB 230510A: Fermi GBM detection
  23. GRB 230510A: Gaoyazi/GOT optical upper limit
  24. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  25. GRB 230510A: Nanshan/NEXT optical afterglow detection
  26. GRB 230506B: Fermi GBM detection
  27. GRB 230510A: Swift-XRT refined Analysis
  28. GRB 230510A: Enhanced Swift-XRT position
  29. GRB 230506C: Fermi GBM detection
  30. GRB 230510A: Swift detection of a burst
  31. GRB 230506B: Swift/UVOT further analysis
  32. GRB 230506C: Swift-XRT refined Analysis
  33. GRB 230506C: Swift-BAT refined analysis
  34. GRB 230506B: Swift-BAT refined analysis
  35. GRB 230506B: LCOGT Optical Upper Limits
  36. GRB 230506C: Swift/UVOT Upper Limits
  37. GRB 230506B: Swift-XRT refined Analysis
  38. GRB 230506C: Swift-XRT analysis
  39. GRB 230506C: Candidate afterglow observation by D50
  40. GRB 230506C: TSHAO possible afterglow candidate
  41. GRB 230506B: Swift/UVOT Detection
  42. GRB 230506C: Swift detection of a burst
  43. Swift GRB230506.71: Global MASTER-Net observations report
  44. GRB 230506B: Swift detection of a burst
  45. GRB 230506B: MASTER optical observations
  46. GRB 230506B: Swift detection of a burst
  47. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  48. GRB 230427A: Swift-BAT refined analysis
  49. GRB 230420A: AROMA-N Optical Upper Limit
  50. GRB 230427A: NOT optical upper limit
  51. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  52. GRB 230427A: Swift/UVOT Detection
  53. GRB 230427A: Gaoyazi/GOT optical upper limit
  54. GRB 230427A: Nanshan/HMT optical upper limit
  55. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  56. GRB 230427A: Swift-XRT refined Analysis
  57. GRB 230427A: GIT optical upper limit
  58. GRB 230427A: Bassano Bresciano Observatory upper limit
  59. GRB 230427A: BOOTES-5/JGT afterglow detection
  60. GRB 230423A(trigger #1165354): Swift-BAT refined analysis
  61. GRB 230427A: AKO Upper Limit
  62. Swift GRB230427.44: Global MASTER-Net observations report
  63. GRB 230427A: MITSuME Akeno optical upper limits
  64. GRB 230427A: Enhanced Swift-XRT position
  65. GRB 230427A: Swift detection of a burst with an optical counterpart
  66. GRB 230423A: Swift/UVOT Upper Limits
  67. GRB 230423A: Swift-XRT refined Analysis
  68. GRB 230423A: Swift-XRT afterglow detection
  69. Swift Trigger 1165354 is probably not a GRB
  70. GRB 230421A: Fermi GBM observation
  71. Konus-Wind detection of GRB 230418A
  72. GRB 230420A: Swift/UVOT Upper Limits
  73. GRB 230421: Swift/BAT-GUANO arcminute localization
  74. GRB 230420A: Swift-BAT refined analysis
  75. GRB 230420A: Swift-XRT refined Analysis
  76. GRB 230420A: MITSuME Akeno optical observation
  77. GRB 230420A: NOT optical afterglow confirmation
  78. GRB 230420A: Gaoyazi/GOT optical upper limit
  79. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  80. GRB 230420A: LCOGT Optical Upper Limit
  81. GRB 230420A: Enhanced Swift-XRT position
  82. IPN triangulation of GRB 230418A (short)
  83. GRB 230420A: Swift detection of a burst
  84. GRB 230418A: AstroSat CZTI detection
  85. GRB 230418A: Swift/BAT-GUANO detection outside the coded FOV
  86. GRB 230414B Swift-BAT refined analysis
  87. GRB 230415A: Fermi GBM detection
  88. GRB 230414B: Swift/UVOT Detection
  89. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations
  90. GRB 230415A: Swift/BAT-GUANO detection
  91. GRB 230307A: iTelescope optical upper limit (likely)
  92. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  93. GRB 230414B: Lulin 40cm-SLT optical limit
  94. GRB 230414B: Bassano Bresciano Observatory optical observations
  95. GRB 230414B: AbAO optical observations
  96. GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  97. GRB 230414B: Swift-XRT refined Analysis
  98. GRB 230414B: Dabancheng/GHOST optical observations
  99. GRB 230414B: SAO RAS optical observations
  100. GRB 230414B: Enhanced Swift-XRT position

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