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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"

28118 results found.

  1. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  2. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  3. GRB 241206A: Fermi GBM Final Real-time Localization
  4. GRB 241204A: DDOTI Upper Limits on the Afterglow
  5. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  6. GRB 241128A : RAPAS follow-up observations
  7. GRB 241201A: GRBAlpha detection
  8. GRB 241204A: Fermi-LAT detection
  9. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  10. EP241202b: Kinder optical counterpart candidate
  11. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  12. GRB 241113B : RAPAS follow-up observation
  13. EP241201a: EP-FXT follow-up observations
  14. Konus-Wind detection of GRB 241130A
  15. EP241201a: BOOTES-5 optical upper limit
  16. EP241202b: EP detection of a fast X-ray transient
  17. IPN triangulation of GRB 241130A
  18. GRB 241130A: EIRSAT-1 GMOD Detection
  19. GRB 241128A: Swift/UVOT Upper Limits
  20. GRB 241130A: Fermi GBM Detection
  21. EP241201a: Kinder optical counterpart candidate
  22. EP241201a: EP detection of a fast X-ray transient
  23. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  24. GRB241201B: Fermi GBM Final Localization
  25. GRB241201B: Fermi GBM Final Localization
  26. GRB 241130A: Fermi GBM Final Real-time Localization
  27. GRB 241130A: Fermi GBM Final Real-time Localization
  28. GRB 241201A: Fermi GBM Final Real-time Localization
  29. IPN triangulation of GRB 241128B
  30. Konus-Wind detection of GRB 241114B
  31. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  32. GRB 241128A: AbAO optical upper limit
  33. GRB 241127A: PRIME near-infrared detection
  34. GRB 241128A: Mondy optical observations
  35. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  36. Swift-XRT observations of IceCube -241127A
  37. GRB 241128A: Swift-XRT refined Analysis
  38. GRB 241129A: Fermi GBM Final Real-time Localization
  39. GRB 241128A: Enhanced Swift-XRT position
  40. GRB 241128A: NOT optical observations
  41. GRB 241128A: LCO optical detection
  42. GRB 241128A: 1.5m OSN optical afterglow detection
  43. GRB 241128A: Swift-XRT afterglow detection
  44. GRB 241128A: Swift detection of a burst
  45. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  46. GRB 241127A: Swift/UVOT Detection
  47. GRB 241127A: Swift-XRT refined Analysis
  48. GRB 241127A: Enhanced Swift-XRT position
  49. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  50. Swift GRB241127.91: Global MASTER-Net OT detection
  51. EP241126a: WFST Observations
  52. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  53. GRB 241127A: Swift detection of a burst with an optical counterpart
  54. Swift GRB241127.91: Global MASTER-Net OT detection
  55. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  56. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  57. EP241126a: Optical Upper limits with Kinder observations
  58. IPN triangulation of GRB 241114B
  59. EP241126a: EP-FXT follow-up observation update
  60. EP241126a: GSP detects optical counterpart
  61. EP241126a: TRT optical counterpart detection
  62. EP241126a: EP detection of a fast X-ray transient
  63. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  64. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  65. GRB 241113B: EP-FXT afterglow detection
  66. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  67. SVOM/GRM detection of a short burst from SGR 1830
  68. GECAM detection of a short burst from SGR 1830
  69. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  70. Konus-Wind detection of GRB 241115D / EP 241115a
  71. GRB 241026A: radio detection with the VLA
  72. EP241125a: EP detection of an X-ray transient
  73. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  74. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  75. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  76. GRB 241120A: GRBAlpha detection
  77. GRB 241113B: SVOM/VT optical afterglow observations
  78. Konus-Wind detection of GRB 241117A
  79. GRB 241105A: ATCA radio detection
  80. IPN triangulation of GRB 241117A
  81. GRB 241026A: VIRT Optical Upper Limit
  82. GRB 241025A: VIRT Optical Upper Limit
  83. Konus-Wind detection of GRB 241120A
  84. GRB241120A: OHP/T193 optical observations
  85. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  86. GRB 241120A: Mondy and AbAO optical observations
  87. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  88. GRB 241113A: Possible ATCA Radio detection
  89. GRB 241114B: Insight-HXMT/HE detection
  90. EP241119a: EP detection of a fast X-ray transient
  91. GRB 241120A: Fermi GBM Final Real-time Localization
  92. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  93. GRB 241112B: Mephisto further optical observations
  94. GRB 241119A: Fermi GBM Final Real-time Localization
  95. GRB 241115a: PRIME near-infrared upper limits
  96. GRB 241118A: Fermi GBM Final Real-time Localization
  97. GRB 241117A: Fermi GBM Detection
  98. GRB 241117B: Fermi GBM Final Real-time Localization
  99. GRB 241117A: Fermi GBM Final Real-time Localization
  100. GRB 241115A: Swift-XRT afterglow detection

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