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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"

37297 results found.

  1. Swift GRB 241209D: Global MASTER-Net observations report
  2. Fermi GRB 241209C: Global MASTER-Net observations report
  3. Fermi GRB 241209E: Global MASTER-Net observations report
  4. GRB 241209E: Fermi GBM Final Real-time Localization
  5. GRB 241209B: Swift ToO observations
  6. GRB 241209A: REM optical/NIR observations
  7. GRB 241209D: Enhanced Swift-XRT position
  8. GRB 241209C: AstroSat CZTI detection
  9. GRB 241209D: Swift detection of a burst
  10. GRB 241209D: Fermi GBM Final Real-time Localization
  11. GRB 241209A: VLT/X-shooter spectroscopy
  12. GRB 241209A: Enhanced Swift-XRT position
  13. GRB 241114B: cubesat Avion detection
  14. GRB 241209A: VLT optical observations
  15. Fermi GRB 241209A: Global MASTER-Net observations report
  16. GRB 241209C: Fermi GBM Final Real-time Localization
  17. GRB 241209A: GOTO optical upper limits
  18. GRB 241209A: Prompt enhanced Swift-XRT position
  19. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  20. GRB 241209A: Swift detection of a short burst
  21. GRB 241209A: Fermi GBM Final Real-time Localization
  22. Fermi GRB 241207B: Global MASTER-Net observations report
  23. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  24. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  25. GRB 241201A: AstroSat CZTI detection
  26. GRB 241206A: DDOTI Upper Limit on the Afterglow
  27. GRB 241207C: MASTER optical observations
  28. GRB 241207C: Tiled Swift observations
  29. GRB 241207C: MAXI/GSC detection
  30. GRB 241207B: Fermi GBM Final Real-time Localization
  31. Fermi GRB 241207A: Global MASTER-Net observations report
  32. EP241206a: EP detection of a fast X-ray transient
  33. GRB 241206A: Fermi GBM observation
  34. GRB 241206C: SVOM/GRM observation of a likely short burst
  35. GRB 241207A: Fermi GBM Final Real-time Localization
  36. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  37. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  38. GRB 241206B: GWAC-F50A optical upper limit
  39. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  40. Fermi GRB 241206A: Global MASTER-Net observations report
  41. GRB 241206A: Fermi GBM Final Real-time Localization
  42. EP241201a: 1.6m Mephisto Optical Upper Limits
  43. GRB 241204A: COLIBRÍ Optical Upper Limit
  44. EP241202b: KAIT optical upper limit
  45. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  46. GRB 241204A: DDOTI Upper Limits on the Afterglow
  47. GRB 241204A: Fermi GBM Observation
  48. Fermi GRB 241204A: Global MASTER-Net observations report
  49. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  50. GRB 241128A : RAPAS follow-up observations
  51. GRB 241201A: GRBAlpha detection
  52. GRB 241204A: Fermi-LAT detection
  53. EP241202b: Upper limits from Fermi-GBM Observations
  54. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  55. EP241202b: Kinder optical counterpart candidate
  56. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  57. GRB 241113B : RAPAS follow-up observation
  58. Konus-Wind detection of GRB 241130A
  59. EP241202b: EP detection of a fast X-ray transient
  60. IPN triangulation of GRB 241130A
  61. GRB 241130A: EIRSAT-1 GMOD Detection
  62. GRB 241128A: Swift/UVOT Upper Limits
  63. GRB 241130A: Fermi GBM Detection
  64. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  65. EP241201a: Kinder optical counterpart candidate
  66. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  67. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  68. GRB241201B: Fermi GBM Final Localization
  69. GRB241201B: Fermi GBM Final Localization
  70. Fermi GRB 241201A: Global MASTER-Net observations report
  71. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  72. GRB 241130A: Fermi GBM Final Real-time Localization
  73. GRB 241130A: Fermi GBM Final Real-time Localization
  74. EP241126a: 1.6m Mephisto Optical Upper Limits
  75. GRB 241201A: Fermi GBM Final Real-time Localization
  76. IPN triangulation of GRB 241128B
  77. Konus-Wind detection of GRB 241114B
  78. GRB 241128A: AbAO optical upper limit
  79. GRB 241128C: SVOM/GRM observation
  80. GRB 241128B: SVOM/GRM observation
  81. GRB 241128A: Swift-BAT refined analysis
  82. GRB 241127A: Swift-BAT refined analysis
  83. GRB 241127A: PRIME near-infrared detection
  84. GRB 241128A: Mondy optical observations
  85. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  86. Swift GRB 241128A: Global MASTER-Net observations report
  87. GRB 241128A: Swift-XRT refined Analysis
  88. GRB 241129A: Fermi GBM Final Real-time Localization
  89. GRB 241128A: Enhanced Swift-XRT position
  90. GRB 241128A: NOT optical observations
  91. GRB 241128A: LCO optical detection
  92. GRB 241128A: 1.5m OSN optical afterglow detection
  93. GRB 241128A: Swift-XRT afterglow detection
  94. GRB 241128A: Swift detection of a burst
  95. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  96. GRB 241127A: Swift/UVOT Detection
  97. GRB 241127A: Swift-XRT refined Analysis
  98. GRB 241127A: SVOM/GRM observation
  99. GRB 241127A: Enhanced Swift-XRT position
  100. GRB 241127A: LCOGT (40-cm) optical counterpart detection

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