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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"

35990 results found.

  1. GRB 231106A: Glowbug gamma-ray detection
  2. GRB 231111A: Xinglong-2.16m optical observations
  3. GRB 231110A: Swift-UVOT Upper Limits
  4. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  5. GRB 231104A: VZLUSAT-2 detection
  6. GRB 231111A: TNG tentative redshift
  7. GRB 231110A: Glowbug gamma-ray detection
  8. GRB 231110A: AstroSat CZTI detection
  9. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  10. GRB 231111A: Leavitt Observatory optical observations
  11. GRB231111A: Optical follow-up observations with Mephisto
  12. GRB 231111A: GMG observation (correction)
  13. GRB 231111A: GMG observation upper limit
  14. GRB 231106B: GRBAlpha detection
  15. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  16. GRB 231110A: Terskol Zeiss-2000 optical upper limit
  17. GRB 231111A: Swift-XRT refined Analysis
  18. GRB 231111A: Mondy optical observations
  19. GRB 231111A: GECAM-C detection of a long burst (correction)
  20. GRB 231110A: GECAM-B detection (correction)
  21. GRB 231111A: Enhanced Swift-XRT position
  22. GRB 231111A: GECAM-C detection of a long burst
  23. GRB 231110A: GECAM detection
  24. GRB 231110A: GOTO optical upper limits
  25. GRB 231110A: SAO RAS optical observations
  26. GRB 231110A: Swift-XRT afterglow detection
  27. GRB231111A: YAHPT Observations
  28. GRB231111A: GIT confirmation of the optical afterglow
  29. GRB 231111A: MASTER OT earlier detection
  30. GRB 231111A: Nanshan/HMT optical observations
  31. GRB 231111A: Swift detection of a burst with an optical counterpart
  32. GRB231110A: WFST Observation and upper limits
  33. GRB 231110A: Swift detection of a burst
  34. GRB 231109A: Fermi GBM Final Localization
  35. Fermi GRB 231108A: Global MASTER-Net observations report
  36. GRB 231108A: Fermi GBM Final Real-time Localization
  37. GRB 231106A: AstroSat CZTI detection
  38. GRB 231106A: CALET Gamma-Ray Burst Monitor detection
  39. GRB 231104A: Swift-BAT refined analysis
  40. Fermi Gamma-ray Burst Monitor trigger 231107654 / 721064512 is not a GRB
  41. GRB 231104A: FRAM-ORM optical limit
  42. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  43. Fermi GRB 231106A: Global MASTER-Net observations report
  44. GRB 231104A: Wendelstein Optical/Infrared Observations
  45. GRB 231104A: NuSTAR Observation of the prompt emission
  46. GRB 231106A: Fermi GBM Final Real-time Localization
  47. GRB 231104A: 3.6m DOT optical upper limit
  48. GRB 231104A: NOT upper limit
  49. GRB 231104A: Fermi GBM Observation
  50. GRB 231104B: Fermi GBM Final Real-time Localization
  51. Fermi GRB 231103A: Global MASTER-Net observations report
  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. GRB 231104A: Fermi GBM Final Real-time Localization
  61. GRB 231103A: Fermi GBM Final Real-time Localization
  62. GRB 231101A: Glowbug gamma-ray detection
  63. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  64. GRB 231101A: Fermi GBM Final Real-time Localization
  65. GRB 231030B: GRBAlpha detection
  66. GRB 231028B: VZLUSAT-2 detection
  67. GRB 231030B: Fermi GBM Detection
  68. GRB 231030B: AstroSat CZTI detection
  69. Fermi GRB 231030B: Global MASTER-Net observations report
  70. IPN triangulation of GRB 231020A
  71. GRB 231030B: BALROG localization (Fermi Trigger 720388704 / GRB 231030832)
  72. GRB 231030B: Fermi GBM Final Real-time Localization
  73. GRB 231028A: Swift-BAT refined analysis
  74. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  75. GRB 231024A: AKO Optical Counterpart Candidate
  76. GRB 231028A: CALET Gamma-Ray Burst Monitor detection
  77. Fermi GRB 231030A: Global MASTER-Net observations report
  78. GRB 231030A: Fermi GBM Final Real-time Localization
  79. GRID detection of GRB 231020A
  80. GRB 231028A: AstroSat CZTI detection
  81. GRB 231028A: Glowbug gamma-ray detection
  82. GRB 231028A: Fermi GBM Detection
  83. Swift GRB 231028A: Global MASTER-Net observations report
  84. GRB 231028A: Swift detection of a burst
  85. GRB 231028A: Fermi GBM Final Real-time Localization
  86. GRB 231019A: Glowbug gamma-ray detection
  87. GRB 231025A: Fermi GBM Observation
  88. GRB 231024A: Fermi GBM Observation
  89. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  90. GRB 231025A: Fermi GBM Final Localization
  91. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  92. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  93. GRB 231020A: AstroSat CZTI detection
  94. GRB 231020B: AstroSat CZTI detection
  95. GRB 231024A: GOTO optical counterpart candidate
  96. GRB 231024A: Fermi GBM Final Localization
  97. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  98. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  99. GRB 231020A: Fermi GBM Detection
  100. GRID detection of GRB 231004A

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