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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"

26119 results found.

  1. GRB 230723B: non-detections from Observatoire de Haute-Provence
  2. GRB 230723B: Optical limit from CAHA
  3. GRB 230723B: Swift/UVOT Upper Limits
  4. Swift GRB 230723B: Global MASTER-Net observations report
  5. Swift-XRT position for GRB 230723B
  6. GRB 230723B: Swift-XRT observations
  7. GRB 230723B: Swift detection of a burst
  8. Swift GRB230720.30: Global MASTER-Net observations report
  9. IPN triangulation of GRB 230715D
  10. Swift Trigger 1180063 is not a GRB
  11. Swift Trigger 1180060 is not a GRB
  12. Swift Trigger 1180055 is not a GRB
  13. IPN triangulation of GRB 230712C (short)
  14. IPN triangulation of GRB 230712A (short)
  15. IceCube-230707A : MAXI upper limit and NICER follow-up observation of Swift J1753.5-0127
  16. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  17. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  18. GRB 230707A: Swift/BAT-GUANO position correction
  19. GRB 230707B: Fermi GBM Observation
  20. IceCube-230707A: No candidates detected by Swift-XRT
  21. Swift Trigger 1178410 is not an astrophysical event
  22. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  23. Swift Trigger 1178410: possible GRB 230709A
  24. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  25. GRB 230707A: Swift-XRT observations
  26. GRB 230707A: Fermi GBM Detection
  27. GRB 230707A: Swift ToO observations
  28. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  29. IBAS trigger number 10311: not a real GRB
  30. GRB 230328B: LBT detection of the likely host galaxy
  31. GRB 230628E: Swift/UVOT Detection
  32. GRB 230628E: Swift-BAT refined analysis
  33. GRB 230628E: ATCA rapid radio follow-up
  34. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  35. IPN triangulation of GRB 230625B (ultra-long)
  36. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  37. GRB 230628E - VLT spectroscopic observations
  38. GRB 230625B: AstroSat CZTI detection
  39. GRB230628E: VLT optical identification of afterglow candidate
  40. GRB 230628E: Swift-XRT refined Analysis
  41. GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
  42. GRB 230628A: Enhanced Swift-XRT position
  43. GRB 230628E: LCOGT Optical Upper Limit
  44. Swift GRB230628.93: Global MASTER-Net observations report
  45. GRB 230628E: Swift detection of a burst
  46. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  47. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  48. Konus-Wind detection of GRB 230616A
  49. GRB 230618A: Swift-BAT refined analysis
  50. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  51. GRB 230622A: Swift-BAT refined analysis
  52. GRB 230623A: Swift-XRT observations
  53. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  54. GRB 230623A: Tiled Swift observations
  55. GRB 230623A: Tiled Swift observations
  56. GRB 230622A: ATCA rapid radio follow-up
  57. GRB 230622A: Swift-XRT refined Analysis
  58. Swift GRB 230622A: Global MASTER-Net observations report
  59. GRB 230622A: Swift detection of a burst
  60. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  61. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  62. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Swift/UVOT detection
  63. IPN triangulation of GRB 230616A (short)
  64. AT2023lcr: Neil Gehrels Swift Observatory X-ray detection
  65. ZTF23aaoohpy/AT2023lcr: OHP/T193 and OHP/T120 optical follow-up observations
  66. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  67. GRB 230618A: Enhanced Swift-XRT position
  68. GRB 230618A: Swift/UVOT Upper Limits
  69. GRB 230618A: Swift-XRT refined Analysis
  70. GRB 230616A: Swift-XRT observations
  71. GRB 230618A: KAIT Optical Observations
  72. Swift GRB 230618A: Global MASTER-Net observations report
  73. GRB230618A: LCOGT Optical Observations
  74. GRB 230618A: Prompt enhanced Swift-XRT position
  75. GRB 230618A: Swift detection of a burst
  76. GRB 230616A: Swift ToO observations
  77. GRB 230616A: AstroSat CZTI detection
  78. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  79. GRB 230614B: Fermi GBM Observation
  80. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  81. GRB 230606A: LCOGT Optical Observations
  82. ZTF23aamxeqf/AT2023jxk: 1.3m DFOT Optical upper limit
  83. GRB 230506B: Chandra localization of the X-ray afterglow
  84. ZTF and GIT Observations of the Candidate Optical Afterglow AT2023jxk
  85. GRB 230606A: Swift-BAT refined analysis
  86. GRB 230606A: Gaoyazi/GOT optical upper limit
  87. GRB 230606A: Fermi GBM Observation
  88. GRB 230606A: BOOTES-5/JGT optical upper limit
  89. GRB 230606A: Swift-XRT refined Analysis
  90. GRB 230606A: Swift/UVOT Upper Limits
  91. GRB 230606A: Enhanced Swift-XRT position
  92. GRB 230606A: Swift detection of a burst
  93. GRB 230510A: Swift-BAT refined analysis
  94. GRB 230523B: GRBAlpha detection
  95. GRB 230523B: Name correction from GCN Circular 33859
  96. GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
  97. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
  98. IPN triangulation of GRB 230518A (short)
  99. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
  100. GRB 230518A: Fermi GBM Observation

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