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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"

36140 results found.

  1. Fermi GBM Sub-Threshold Detection of GRB 240123A
  2. GRB 240123A: Mondy continued optical observations + correction of the GRB name in GCN 35605
  3. GRB 240123B: Fermi GBM Final Real-time Localization
  4. GRB 240118A: Swift/UVOT Upper Limits
  5. GRB 240122B: Glowbug gamma-ray detection
  6. GRB 240123A: Mondy optical afterglow observations
  7. Konus-Wind detection of GRB 240112A
  8. GRB 240123A: Swift detection of a burst with a possible optical counterpart
  9. GRB 240122A: Swift-XRT afterglow detection
  10. GRB 240122A: VLT/X-shooter redshift confirmation
  11. GRB 240122A: Redshift from OSIRIS+/GTC
  12. GRB 240122A: LT non-detection of GOTO candidate counterpart confirms fading
  13. GRB 240122A: GOTO optical counterpart candidate
  14. GRB 240122A: Tiled Swift observations
  15. Konus-Wind detection of GRB 240119A (short/hard)
  16. GRB 240122A: MAXI/GSC detection
  17. IPN triangulation of GRB 240119A (short)
  18. GRB 240119A: GECAM detection of a short burst
  19. GRB 240118C: GECAM-B detection of a long burst
  20. GRB 240119A: AstroSat CZTI detection of a short burst
  21. GRB 240118A: Mondy optical observations
  22. GRB 240118A: Swift-XRT afterglow detection
  23. GRB 240118C: Fermi GBM Observation
  24. Fermi GRB 240119A: Global MASTER-Net observations report
  25. GRB 240119A: Fermi GBM Final Localization
  26. GRB 240117A: CALET Gamma-Ray Burst Monitor detection
  27. GRB 240118C: Swift/BAT-GUANO detection of a burst
  28. GRB 240118A: GRBAlpha detection
  29. GRB 240115A: Fermi GBM Observation
  30. GRB 240118C: Fermi GBM Final Localization
  31. GRB 240118D: AstroSat CZTI detection
  32. GRB 240117A: AstroSat CZTI detection
  33. GRB 240118A: Swift ToO observations
  34. GRB 240118A: AbAO optical upper limit
  35. Fermi GRB 240118B: Global MASTER-Net observations report
  36. GRB 240118A: NuSTAR Offline Analysis of the GRB
  37. GRB 240117A: Glowbug gamma-ray detection
  38. GRB 240118A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  39. Konus-Wind detection of GRB 240118A
  40. GRB 240118C: BALROG localization (Fermi Trigger 727291408 / GRB 240118725)
  41. GRB 240118A: NuSTAR Detection of a Long GRB
  42. GRB 240118A: Fermi GBM Observation
  43. GRB 240118B: Fermi GBM Final Real-time Localization
  44. GRB 240118A: Fermi-LAT detection
  45. GRID detection of GRB 231230A
  46. GRB 240118A: Fermi GBM Final Real-time Localization
  47. GRB 240115A: Swift/BAT-GUANO detection of a short burst
  48. IPN triangulation of GRB 240112A (long)
  49. GRB 240115B: AstroSat CZTI detection
  50. LIGO/Virgo/KAGRA S240109a: Upper limits from Swift/BAT-GUANO
  51. GRB 240115B: Fermi GBM Detection
  52. GRB 240112D: Glowbug gamma-ray detection
  53. GRB 240112C: Glowbug gamma-ray detection
  54. GRB 240112C: VZLUSAT-2 detection
  55. GRB 240107A: VZLUSAT-2 detection
  56. Fermi GRB 240115B: Global MASTER-Net observations report
  57. GRB 240115B: A long GRB detected by INTEGRAL
  58. GRB 240115B: Fermi GBM Final Real-time Localization
  59. Konus-Wind detection of GRB 240112C
  60. Fermi GRB 240115A: Global MASTER-Net observations report
  61. GRB 240115A: Fermi GBM Final Real-time Localization
  62. GRB 240112C: GRBAlpha detection
  63. GRB 240114A: MAXI/GSC detection
  64. GRB 240112C: Swift/UVOT Detection
  65. GRB 240112C: Fermi GBM Detection
  66. GRB 240112C: Swift-XRT refined Analysis
  67. GRB 240112C: SAO RAS optical observations
  68. GRB 240112E: Fermi GBM Final Localization
  69. Fermi GRB 240112D: Global MASTER-Net observations report
  70. GRB 240112D: Fermi GBM Final Real-time Localization
  71. Swift GRB 240112C: Global MASTER-Net observations report
  72. Fermi GRB 240112B: Global MASTER-Net observations report
  73. GRB 240109A: Swift-BAT refined analysis
  74. GRB 240112C: Swift detection of a burst with an optical counterpart
  75. GRB 240112B: Fermi GBM Final Real-time Localization
  76. GRB 240112A: GECAM detection of a burst
  77. GRB 240109A: Fermi GBM Observation
  78. GRB 240110A: AstroSat CZTI detection
  79. GRB 240108A: Glowbug gamma-ray detection
  80. GRB 231214A: ATCA Radio Upper Limits
  81. GRB 240106B: Glowbug gamma-ray detection
  82. GRB 240106A: Glowbug gamma-ray detection
  83. IceCube-240105A: Upper limits from a search for additional neutrino events in IceCube
  84. GRB 240109B: Fermi GBM Final Real-time Localization
  85. Konus-Wind detection of GRB 240101C
  86. GRB 231215A: radio detection with the VLA
  87. GRB 230818A: further radio observations with the VLA
  88. GRB 230812B: further radio observations with the VLA
  89. GRB 240107A: AstroSat CZTI detection
  90. GRB 240109A: Swift detection of a short burst
  91. LIGO/Virgo/KAGRA S240104bl: Upper limits from Swift/BAT-GUANO
  92. GRB 240106A: GRBAlpha detection
  93. GRB 240107A: MAXI/GSC detection
  94. GRB 240106B: Fermi GBM Final Real-time Localization
  95. GRB 240106A: Fermi GBM Final Real-time Localization
  96. IPN triangulation of GRB 240101C (short)
  97. GRB GRB240101C: Fermi GBM observation
  98. GRB 240101A: 1.3m DFOT optical observations
  99. GRB 240102A: 1.3m DFOT optical upper limit
  100. GRB 240101B: 1.3m DFOT optical upper limit

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