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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"

868 results found.

  1. LIGO/Virgo S230611l: Global MASTER-Net observations report
  2. LIGO/Virgo/KAGRA S230609u: Identification of a GW compact binary merger candidate
  3. LIGO/Virgo/KAGRA S230608as: Identification of a GW compact binary merger candidate
  4. LIGO/Virgo/KAGRA S230606d: Identification of a GW compact binary merger candidate
  5. LIGO/Virgo/KAGRA S230605o: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo/KAGRA S230601bf: Identification of a GW compact binary merger candidate
  7. IPN triangulation of GRB 230430A (short)
  8. IPN triangulation of GRB 230418A (short)
  9. GRB 230405B: Fermi GBM Observation
  10. IPN triangulation of GRB 230304B
  11. IPN triangulation of GRB 230308A (short/bright)
  12. Further improved IPN localization for GRB 230307A
  13. Swift GRB230311.84: Global MASTER-Net observations report
  14. Improved IPN localization for GRB 230307A
  15. IPN triangulation of GRB 230307A (long/very bright)
  16. Konus-Wind detection of GRB 230217A
  17. GRB 230216A: Swift detection of a burst
  18. IPN triangulation of GRB 230209B
  19. IPN triangulation of GRB 230116B (short)
  20. IPN triangulation of GRB 221226A
  21. GRB 221216A: Detection by VZLUSAT-2
  22. IPN triangulation of GRB 221209A (long)
  23. GRB 221022B: AstroSat CZTI detection
  24. IPN triangulation of GRB 221017A (long)
  25. IPN triangulation of GRB 220927A (long)
  26. IPN triangulation of GRB 220624A
  27. IPN triangulation of GRB 220617A (short)
  28. IPN triangulation of GRB 220613A
  29. IPN triangulation of GRB 220609B
  30. IPN triangulation of GRB 220601A (long)
  31. IPN triangulation of GRB 220525A
  32. IPN triangulation of GRB 220524B
  33. IPN triangulation of GRB 220524A
  34. IPN triangulation of GRB 220522B
  35. IPN triangulation of GRB 220521B
  36. GRB 220521A: Fermi GBM detection
  37. IPN triangulation of GRB 220519A
  38. IPN triangulation of GRB 220426A
  39. IPN triangulation of GRB 220411A
  40. IPN triangulation of short/soft GRB 220406A
  41. IPN triangulation of GRB 220403C
  42. GRB 220403B: Swift/UVOT Detection
  43. GRB 220403B: Swift detection of a burst with an optical counterpart
  44. IPN triangulation of GRB 220320A
  45. IPN triangulation of GRB 220310A
  46. IPN triangulation of GRB 220305B
  47. IPN triangulation of GRB 220222A
  48. GCN Circ.draft on GRB 220222A
  49. IPN triangulation of GRB 220219A
  50. IPN triangulation of GRB 220209A
  51. Fermi GRB 220211A: Global MASTER-Net observations report
  52. IPN triangulation of GRB 220128A (long)
  53. IPN triangulation of GRB 220124A
  54. IPN triangulation of a bright burst from SGR 1935+2154
  55. IPN triangulation of GRB 211226A
  56. Konus-Wind detection of GRB 220101A
  57. IPN triangulation of GRB 211219A
  58. GRB 211227A: Swift-XRT refined Analysis
  59. IPN triangulation of GRB 211204C
  60. IPN triangulation of GRB 211120A
  61. GRB 211105A: AGILE detection of a burst
  62. IPN triangulation of GRB 211022A
  63. GRB 211024B: Swift-XRT refined Analysis
  64. IPN Triangulation of GRB 211019A
  65. IPN Triangulation of GRB 210927B
  66. IPN triangulation of GRB 210925B
  67. GRB 210919A: Swift-XRT refined Analysis
  68. Fermi trigger No 652906639: Global MASTER-Net observations report
  69. GRB 210802A: DDOTI Upper Limits
  70. GRB 210619B: Swift-BAT refined analysis
  71. GRB 210610A: MITSuME Ishigaki optical observation
  72. IPN triangulation of GRB 210606B
  73. IPN triangulation of GRB 210524A
  74. IPN triangulation of GRB 210518A
  75. IPN triangulation of GRB 210511B
  76. IPN triangulation of GRB 210427A
  77. IPN triangulation of GRB 210424B (short/hard)
  78. IPN triangulation of GRB 210324C
  79. GRB 210226A: Ondrejov BART/SBT optical limit
  80. IPN triangulation of GRB 210204A
  81. GRB 210205A: MITSuME Ishigaki optical observation
  82. IPN triangulation of GRB 210124B (short)
  83. IPN triangulation of GRB 210121A
  84. GRB 210112A: Swift-BAT refined analysis
  85. GRB 210104A: MITSuME Ishigaki optical observation
  86. IPN triangulation of GRB 201218A
  87. Integral GRB201214.26: Global MASTER-Net observations report
  88. IPN triangulation of GRB 201207A
  89. Konus-Wind observation of GRB 201103B
  90. GRB 201104B: Swift-XRT refined Analysis
  91. IPN triangulation of GRB 201103B (consistent with ZTF20acozryr/AT2020yxz)
  92. GRB 201021C: Swift-XRT refined Analysis
  93. GRB 201021C: Swift/UVOT Detection
  94. GRB 201021C: Swift detection of a burst with an optical counterpart
  95. IPN triangulation of GRB 200907A (short)
  96. Fermi GRB 200908A: Global MASTER-Net observations report
  97. IPN triangulation of GRB 200903E
  98. IPN triangulation of GRB 200826B
  99. IPN triangulation of GRB 200826A (short/bright)
  100. IPN triangulation of GRB 200815A (short)

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