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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"

19611 results found.

  1. GRB 230805B : MITSuME Akeno optical upper limits
  2. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  3. GRB 230805B: Fermi GBM observation
  4. GRB 230805B: Enhanced Swift-XRT position
  5. GRB 230805B: Swift/UVOT Upper Limits
  6. GRB 230805B: Bassano Bresciano observatory upper limit
  7. GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection
  8. GRB 230805B: Swift-XRT refined Analysis
  9. Swift GRB 230805B: Global MASTER-Net observations report
  10. GRB 230805B: Swift detection of a burst
  11. GRB 230802A: Fermi GBM observation
  12. GRB 230802A: Swift-BAT refined analysis
  13. GRB 230802A: Swift/UVOT Upper Limits
  14. Swift GRB 230802A: Global MASTER-Net observations report
  15. GRB 230802A: BOOTES-5/JGT optical upper limit
  16. GRB 230802A: Swift-XRT refined Analysis
  17. GRB 230802A: Enhanced Swift-XRT position
  18. GRB 230802A: Swift detection of a burst
  19. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  20. GRB 230728A: Swift-BAT refined analysis
  21. GRB 230723B: Swift-BAT refined analysis
  22. GRB 230723B: MITSuME Ishigaki optical observation
  23. GRB 230728A: BOOTES-1 optical upper limit
  24. GRB 230728A: Fermi GBM Observation
  25. GRB 230728A: LCOGT Optical Upper Limit
  26. GRB 230728A: Swift/UVOT Upper Limits
  27. GRB 230728A: Swift-XRT refined Analysis
  28. GRB 230728A: Enhanced Swift-XRT position
  29. GRB 230728A: NOT optical observations and possible host galaxy
  30. GRB 230727A: AstroSat CZTI detection
  31. GRB 230728A: Swift detection of a burst
  32. Swift GRB230728.12: Global MASTER-Net observations report
  33. GRB 230727A: Swift/BAT-GUANO detection of a burst
  34. GRB 230723B: MITSuME Akeno optical afterglow candidate detection
  35. IBAS trigger number 10337: not a real GRB
  36. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  37. GRB 230723B: Leavitt Observatory upper limit
  38. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  39. GRB 230723B: Montarrenti Observatory upper limit
  40. GRB 230723B: Bassano Bresciano Observatory upper limit
  41. GRB 230723B: Fermi GBM observation
  42. GRB 230723B: Swift-XRT refined Analysis
  43. GRB 230723B: Swift/UVOT Upper Limits
  44. Swift GRB 230723B: Global MASTER-Net observations report
  45. Swift-XRT position for GRB 230723B
  46. GRB 230723B: Swift-XRT observations
  47. GRB 230723B: Swift detection of a burst
  48. Swift GRB230720.30: Global MASTER-Net observations report
  49. IPN triangulation of GRB 230715D
  50. Swift Trigger 1180063 is not a GRB
  51. Swift Trigger 1180060 is not a GRB
  52. Swift Trigger 1180055 is not a GRB
  53. IPN triangulation of GRB 230712C (short)
  54. IPN triangulation of GRB 230712A (short)
  55. IceCube-230707A : MAXI upper limit and NICER follow-up observation of Swift J1753.5-0127
  56. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  57. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  58. GRB 230707A: Swift/BAT-GUANO position correction
  59. GRB 230707B: Fermi GBM Observation
  60. IceCube-230707A: No candidates detected by Swift-XRT
  61. Swift Trigger 1178410 is not an astrophysical event
  62. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  63. Swift Trigger 1178410: possible GRB 230709A
  64. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  65. GRB 230707A: Swift-XRT observations
  66. GRB 230707A: Fermi GBM Detection
  67. GRB 230707A: Swift ToO observations
  68. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  69. IBAS trigger number 10311: not a real GRB
  70. GRB 230328B: LBT detection of the likely host galaxy
  71. GRB 230628E: Swift/UVOT Detection
  72. GRB 230628E: Swift-BAT refined analysis
  73. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  74. IPN triangulation of GRB 230625B (ultra-long)
  75. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  76. GRB 230625B: AstroSat CZTI detection
  77. GRB230628E: VLT optical identification of afterglow candidate
  78. GRB 230628E: Swift-XRT refined Analysis
  79. GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
  80. GRB 230628A: Enhanced Swift-XRT position
  81. GRB 230628E: LCOGT Optical Upper Limit
  82. Swift GRB230628.93: Global MASTER-Net observations report
  83. GRB 230628E: Swift detection of a burst
  84. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  85. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  86. Konus-Wind detection of GRB 230616A
  87. GRB 230618A: Swift-BAT refined analysis
  88. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  89. GRB 230622A: Swift-BAT refined analysis
  90. GRB 230623A: Swift-XRT observations
  91. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  92. GRB 230623A: Tiled Swift observations
  93. GRB 230623A: Tiled Swift observations
  94. GRB 230622A: Swift-XRT refined Analysis
  95. Swift GRB 230622A: Global MASTER-Net observations report
  96. GRB 230622A: Swift detection of a burst
  97. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  98. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Swift/UVOT detection
  99. IPN triangulation of GRB 230616A (short)
  100. AT2023lcr: Neil Gehrels Swift Observatory X-ray detection

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