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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

20008 results found.

  1. GRB 231117A : MITSuME Akeno optical upper limits
  2. GRB 231117A: AGILE detection of a bright short burst
  3. GRB 231117A: Enhanced Swift-XRT position
  4. GRB 231117A: GOTO optical upper limits
  5. GRB 231117A: AstroSat CZTI detection of a bright short burst
  6. GRB 231117A: Swift detection of a bright short burst
  7. GRB 231111A: Swift/UVOT Detection
  8. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  9. GRB 231115A: Swift-XRT and Swift-UVOT observations
  10. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  11. GRB 231115A: Swift ToO observations
  12. GRB 231111A: Swift-BAT refined analysis
  13. GECAM-B observation of a short burst from SGR J1555-5402
  14. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  15. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  16. GRB 231110A: Swift-BAT refined analysis
  17. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  18. GRB 231111A: Xinglong-2.16m optical observations
  19. GRB 231110A: Swift-UVOT Upper Limits
  20. GRB 231104A: VZLUSAT-2 detection
  21. GRB 231110A: Glowbug gamma-ray detection
  22. GRB 231110A: AstroSat CZTI detection
  23. GRB 231111A: Leavitt Observatory optical observations
  24. GRB231111A: Optical follow-up observations with Mephisto
  25. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  26. GRB 231110A: Terskol Zeiss-2000 optical upper limit
  27. GRB 231111A: Swift-XRT refined Analysis
  28. GRB 231111A: Mondy optical observations
  29. GRB 231111A: GECAM-C detection of a long burst (correction)
  30. GRB 231110A: GECAM-B detection (correction)
  31. GRB 231111A: Enhanced Swift-XRT position
  32. GRB 231111A: GECAM-C detection of a long burst
  33. GRB 231110A: GECAM detection
  34. GRB 231110A: SAO RAS optical observations
  35. GRB 231110A: Swift-XRT afterglow detection
  36. GRB231111A: YAHPT Observations
  37. GRB231111A: GIT confirmation of the optical afterglow
  38. GRB 231111A: MASTER OT earlier detection
  39. GRB 231111A: Nanshan/HMT optical observations
  40. GRB 231111A: Swift detection of a burst with an optical counterpart
  41. Swift GRB231111.60: Global MASTER-Net observations report
  42. GRB231110A: WFST Observation and upper limits
  43. Swift GRB231110.89: Global MASTER-Net observations report
  44. GRB 231110A: Swift detection of a burst
  45. GRB 231104A: Swift-BAT refined analysis
  46. GRB 231104A: FRAM-ORM optical limit
  47. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  48. GRB 231104A: NuSTAR Observation of the prompt emission
  49. GRB 231104A: 3.6m DOT optical upper limit
  50. GRB 231104A: NOT upper limit
  51. GRB 231104A: Fermi GBM Observation
  52. GRB 231104A: AKO Upper Limit
  53. GRB 231104A: AstroSat CZTI detection
  54. GRB 231104A: Swift-XRT refined Analysis
  55. GRB 231104A: Fermi-LAT detection
  56. GRB 231104A: Swift/UVOT Upper Limits
  57. GRB 231104A: Enhanced Swift-XRT position
  58. GRB231104A: LCOGT Optical Upper Limits
  59. GRB 231104A: Swift detection of a bright burst
  60. Swift GRB231104.07: Global MASTER-Net observations report
  61. New Swift-BAT/GUANO and IceCube Notices Available via GCN Kafka
  62. IPN triangulation of GRB 231020A
  63. GRB 231028A: Swift-BAT refined analysis
  64. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  65. GRB 231028A: CALET Gamma-Ray Burst Monitor detection
  66. GRB 231028A: AstroSat CZTI detection
  67. GRB 231028A: Glowbug gamma-ray detection
  68. GRB 231028A: Fermi GBM Detection
  69. Swift GRB 231028A: Global MASTER-Net observations report
  70. GRB 231028A: Swift detection of a burst
  71. GRB 231025A: Fermi GBM Observation
  72. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  73. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  74. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  75. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  76. GRB 231017A: 1.3m DFOT Optical upper limit
  77. GRB 231018A: Glowbug gamma-ray detection
  78. IPN triangulation of GRB 231018A
  79. GRB 231017A: Swift/UVOT Upper Limit
  80. GRB 230911C: ATCA detection of possible radio counterpart
  81. GRB 231017A: GOTO optical upper limits
  82. GRB 231017A: JinShan optical upper limit
  83. GRB 231017A: Las Cumbres optical upper limit
  84. GRB 231017A: LCOGT Optical Upper Limits
  85. GRB231017A: GROWTH-India upper limits on the optical afterglow
  86. GRB 231017A: Fermi GBM Detection
  87. GRB 231017A: Swift-XRT observations
  88. GRB 231017A: Swift ToO observations
  89. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  90. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  91. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  92. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  93. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  94. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  95. NuEm-230927A: Swift-XRT follow-up
  96. Swift Triggers 1192745 and 1192747 are not astrophysical events
  97. Swift Triggers 1192740, 1192742 and 1192743 are not astrophysical events
  98. Swift Triggers 1192735 and 1192737 are not astrophysical events
  99. Konus-Wind detection of GRB 230919A
  100. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO

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