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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').
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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"

19596 results found.

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

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