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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 230728A: BOOTES-1 optical upper limit
  2. GRB 230728A: Fermi GBM Observation
  3. GRB 230728A: LCOGT Optical Upper Limit
  4. GRB 230728A: Swift/UVOT Upper Limits
  5. GRB 230728A: Swift-XRT refined Analysis
  6. GRB 230728A: Enhanced Swift-XRT position
  7. GRB 230728A: NOT optical observations and possible host galaxy
  8. GRB 230727A: AstroSat CZTI detection
  9. GRB 230728A: Swift detection of a burst
  10. Swift GRB230728.12: Global MASTER-Net observations report
  11. GRB 230727A: Swift/BAT-GUANO detection of a burst
  12. GRB 230723B: MITSuME Akeno optical afterglow candidate detection
  13. IBAS trigger number 10337: not a real GRB
  14. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  15. GRB 230723B: Leavitt Observatory upper limit
  16. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  17. GRB 230723B: Montarrenti Observatory upper limit
  18. GRB 230723B: Bassano Bresciano Observatory upper limit
  19. GRB 230723B: Fermi GBM observation
  20. GRB 230723B: Swift-XRT refined Analysis
  21. GRB 230723B: Swift/UVOT Upper Limits
  22. Swift GRB 230723B: Global MASTER-Net observations report
  23. Swift-XRT position for GRB 230723B
  24. GRB 230723B: Swift-XRT observations
  25. GRB 230723B: Swift detection of a burst
  26. Swift GRB230720.30: Global MASTER-Net observations report
  27. IPN triangulation of GRB 230715D
  28. Swift Trigger 1180063 is not a GRB
  29. Swift Trigger 1180060 is not a GRB
  30. Swift Trigger 1180055 is not a GRB
  31. IPN triangulation of GRB 230712C (short)
  32. IPN triangulation of GRB 230712A (short)
  33. IceCube-230707A : MAXI upper limit and NICER follow-up observation of Swift J1753.5-0127
  34. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  35. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  36. GRB 230707A: Swift/BAT-GUANO position correction
  37. GRB 230707B: Fermi GBM Observation
  38. IceCube-230707A: No candidates detected by Swift-XRT
  39. Swift Trigger 1178410 is not an astrophysical event
  40. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  41. Swift Trigger 1178410: possible GRB 230709A
  42. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  43. GRB 230707A: Swift-XRT observations
  44. GRB 230707A: Fermi GBM Detection
  45. GRB 230707A: Swift ToO observations
  46. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  47. IBAS trigger number 10311: not a real GRB
  48. GRB 230328B: LBT detection of the likely host galaxy
  49. GRB 230628E: Swift/UVOT Detection
  50. GRB 230628E: Swift-BAT refined analysis
  51. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  52. IPN triangulation of GRB 230625B (ultra-long)
  53. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  54. GRB 230625B: AstroSat CZTI detection
  55. GRB230628E: VLT optical identification of afterglow candidate
  56. GRB 230628E: Swift-XRT refined Analysis
  57. GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
  58. GRB 230628A: Enhanced Swift-XRT position
  59. GRB 230628E: LCOGT Optical Upper Limit
  60. Swift GRB230628.93: Global MASTER-Net observations report
  61. GRB 230628E: Swift detection of a burst
  62. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  63. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  64. Konus-Wind detection of GRB 230616A
  65. GRB 230618A: Swift-BAT refined analysis
  66. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  67. GRB 230622A: Swift-BAT refined analysis
  68. GRB 230623A: Swift-XRT observations
  69. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  70. GRB 230623A: Tiled Swift observations
  71. GRB 230623A: Tiled Swift observations
  72. GRB 230622A: Swift-XRT refined Analysis
  73. Swift GRB 230622A: Global MASTER-Net observations report
  74. GRB 230622A: Swift detection of a burst
  75. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  76. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Swift/UVOT detection
  77. IPN triangulation of GRB 230616A (short)
  78. AT2023lcr: Neil Gehrels Swift Observatory X-ray detection
  79. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  80. GRB 230618A: Enhanced Swift-XRT position
  81. GRB 230618A: Swift/UVOT Upper Limits
  82. GRB 230618A: Swift-XRT refined Analysis
  83. GRB 230616A: Swift-XRT observations
  84. GRB 230618A: KAIT Optical Observations
  85. Swift GRB 230618A: Global MASTER-Net observations report
  86. GRB230618A: LCOGT Optical Observations
  87. GRB 230618A: Prompt enhanced Swift-XRT position
  88. GRB 230618A: Swift detection of a burst
  89. GRB 230616A: Swift ToO observations
  90. GRB 230616A: AstroSat CZTI detection
  91. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  92. GRB 230614B: Fermi GBM Observation
  93. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  94. GRB 230606A: LCOGT Optical Observations
  95. GRB 230606A: Swift-BAT refined analysis
  96. GRB 230606A: Gaoyazi/GOT optical upper limit
  97. GRB 230606A: Fermi GBM Observation
  98. GRB 230606A: BOOTES-5/JGT optical upper limit
  99. GRB 230606A: Swift-XRT refined Analysis
  100. GRB 230606A: Swift/UVOT Upper Limits

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