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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').
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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"

28198 results found.

  1. EP241201a: Kinder optical counterpart candidate
  2. EP241201a: EP detection of a fast X-ray transient
  3. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  4. GRB241201B: Fermi GBM Final Localization
  5. GRB241201B: Fermi GBM Final Localization
  6. GRB 241130A: Fermi GBM Final Real-time Localization
  7. GRB 241130A: Fermi GBM Final Real-time Localization
  8. GRB 241201A: Fermi GBM Final Real-time Localization
  9. IPN triangulation of GRB 241128B
  10. Konus-Wind detection of GRB 241114B
  11. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  12. GRB 241128A: AbAO optical upper limit
  13. GRB 241127A: PRIME near-infrared detection
  14. GRB 241128A: Mondy optical observations
  15. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  16. Swift-XRT observations of IceCube -241127A
  17. GRB 241128A: Swift-XRT refined Analysis
  18. GRB 241129A: Fermi GBM Final Real-time Localization
  19. GRB 241128A: Enhanced Swift-XRT position
  20. GRB 241128A: NOT optical observations
  21. GRB 241128A: LCO optical detection
  22. GRB 241128A: 1.5m OSN optical afterglow detection
  23. GRB 241128A: Swift-XRT afterglow detection
  24. GRB 241128A: Swift detection of a burst
  25. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  26. GRB 241127A: Swift/UVOT Detection
  27. GRB 241127A: Swift-XRT refined Analysis
  28. GRB 241127A: Enhanced Swift-XRT position
  29. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  30. Swift GRB241127.91: Global MASTER-Net OT detection
  31. EP241126a: WFST Observations
  32. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  33. GRB 241127A: Swift detection of a burst with an optical counterpart
  34. Swift GRB241127.91: Global MASTER-Net OT detection
  35. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  36. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  37. EP241126a: Optical Upper limits with Kinder observations
  38. IPN triangulation of GRB 241114B
  39. EP241126a: EP-FXT follow-up observation update
  40. EP241126a: GSP detects optical counterpart
  41. EP241126a: TRT optical counterpart detection
  42. EP241126a: EP detection of a fast X-ray transient
  43. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  44. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  45. GRB 241113B: EP-FXT afterglow detection
  46. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  47. SVOM/GRM detection of a short burst from SGR 1830
  48. GECAM detection of a short burst from SGR 1830
  49. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  50. Konus-Wind detection of GRB 241115D / EP 241115a
  51. GRB 241026A: radio detection with the VLA
  52. EP241125a: EP detection of an X-ray transient
  53. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  54. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  55. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  56. GRB 241120A: GRBAlpha detection
  57. GRB 241113B: SVOM/VT optical afterglow observations
  58. Konus-Wind detection of GRB 241117A
  59. GRB 241105A: ATCA radio detection
  60. IPN triangulation of GRB 241117A
  61. GRB 241026A: VIRT Optical Upper Limit
  62. GRB 241025A: VIRT Optical Upper Limit
  63. Konus-Wind detection of GRB 241120A
  64. GRB241120A: OHP/T193 optical observations
  65. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  66. GRB 241120A: Mondy and AbAO optical observations
  67. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  68. GRB 241113A: Possible ATCA Radio detection
  69. GRB 241114B: Insight-HXMT/HE detection
  70. EP241119a: EP detection of a fast X-ray transient
  71. GRB 241120A: Fermi GBM Final Real-time Localization
  72. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  73. GRB 241112B: Mephisto further optical observations
  74. GRB 241119A: Fermi GBM Final Real-time Localization
  75. GRB 241115a: PRIME near-infrared upper limits
  76. GRB 241118A: Fermi GBM Final Real-time Localization
  77. GRB 241117A: Fermi GBM Detection
  78. GRB 241117B: Fermi GBM Final Real-time Localization
  79. GRB 241117A: Fermi GBM Final Real-time Localization
  80. GRB 241115A: Swift-XRT afterglow detection
  81. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  82. GRB 241113B: Mephisto upper limits
  83. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  84. EP241113a: Swift XRT weak detection
  85. GRB 241115A: LCOGT Optical Upper Limits
  86. GRB 241115B: Fermi GBM Final Real-time Localization
  87. EP241115a: EP detection of a fast X-ray transient
  88. EP241113a: No Detection in Fermi-GBM Observations
  89. GRB 241115A: Swift detection of a burst
  90. GRB 241115A: Fermi GBM Final Real-time Localization
  91. EP 241113a: LBT possible optical counterpart
  92. GRB 241113B: KAIT Optical Afterglow Candidate
  93. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  94. GRB 241113A: PRIME near-infrared upper limits
  95. GRB 241114A: Fermi GBM Final Real-time Localization
  96. GRB 241113A: J-band observations with WINTER
  97. GRB 241030A: LCO optical observation
  98. GRB 241113B: Swift-XRT observations
  99. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  100. GRB 241113A: KAIT optical observations

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