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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"

28126 results found.

  1. GRB 241206A: DDOTI Upper Limit on the Afterglow
  2. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  3. EP241206a: BOOTES Global Network optical limits
  4. GRB 241207C: Tiled Swift observations
  5. GRB 241207C: MAXI/GSC detection
  6. GRB 241207B: Fermi GBM Final Real-time Localization
  7. EP241206a: EP detection of a fast X-ray transient
  8. GRB 241207A: Fermi GBM Final Real-time Localization
  9. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  10. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  11. GRB 241206A: Fermi GBM Final Real-time Localization
  12. GRB 241204A: DDOTI Upper Limits on the Afterglow
  13. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  14. GRB 241128A : RAPAS follow-up observations
  15. GRB 241201A: GRBAlpha detection
  16. GRB 241204A: Fermi-LAT detection
  17. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  18. EP241202b: Kinder optical counterpart candidate
  19. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  20. GRB 241113B : RAPAS follow-up observation
  21. EP241201a: EP-FXT follow-up observations
  22. Konus-Wind detection of GRB 241130A
  23. EP241201a: BOOTES-5 optical upper limit
  24. EP241202b: EP detection of a fast X-ray transient
  25. IPN triangulation of GRB 241130A
  26. GRB 241130A: EIRSAT-1 GMOD Detection
  27. GRB 241128A: Swift/UVOT Upper Limits
  28. GRB 241130A: Fermi GBM Detection
  29. EP241201a: Kinder optical counterpart candidate
  30. EP241201a: EP detection of a fast X-ray transient
  31. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  32. GRB241201B: Fermi GBM Final Localization
  33. GRB241201B: Fermi GBM Final Localization
  34. GRB 241130A: Fermi GBM Final Real-time Localization
  35. GRB 241130A: Fermi GBM Final Real-time Localization
  36. GRB 241201A: Fermi GBM Final Real-time Localization
  37. IPN triangulation of GRB 241128B
  38. Konus-Wind detection of GRB 241114B
  39. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  40. GRB 241128A: AbAO optical upper limit
  41. GRB 241127A: PRIME near-infrared detection
  42. GRB 241128A: Mondy optical observations
  43. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  44. Swift-XRT observations of IceCube -241127A
  45. GRB 241128A: Swift-XRT refined Analysis
  46. GRB 241129A: Fermi GBM Final Real-time Localization
  47. GRB 241128A: Enhanced Swift-XRT position
  48. GRB 241128A: NOT optical observations
  49. GRB 241128A: LCO optical detection
  50. GRB 241128A: 1.5m OSN optical afterglow detection
  51. GRB 241128A: Swift-XRT afterglow detection
  52. GRB 241128A: Swift detection of a burst
  53. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  54. GRB 241127A: Swift/UVOT Detection
  55. GRB 241127A: Swift-XRT refined Analysis
  56. GRB 241127A: Enhanced Swift-XRT position
  57. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  58. Swift GRB241127.91: Global MASTER-Net OT detection
  59. EP241126a: WFST Observations
  60. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  61. GRB 241127A: Swift detection of a burst with an optical counterpart
  62. Swift GRB241127.91: Global MASTER-Net OT detection
  63. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  64. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  65. EP241126a: Optical Upper limits with Kinder observations
  66. IPN triangulation of GRB 241114B
  67. EP241126a: EP-FXT follow-up observation update
  68. EP241126a: GSP detects optical counterpart
  69. EP241126a: TRT optical counterpart detection
  70. EP241126a: EP detection of a fast X-ray transient
  71. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  72. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  73. GRB 241113B: EP-FXT afterglow detection
  74. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  75. SVOM/GRM detection of a short burst from SGR 1830
  76. GECAM detection of a short burst from SGR 1830
  77. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  78. Konus-Wind detection of GRB 241115D / EP 241115a
  79. GRB 241026A: radio detection with the VLA
  80. EP241125a: EP detection of an X-ray transient
  81. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  82. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  83. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  84. GRB 241120A: GRBAlpha detection
  85. GRB 241113B: SVOM/VT optical afterglow observations
  86. Konus-Wind detection of GRB 241117A
  87. GRB 241105A: ATCA radio detection
  88. IPN triangulation of GRB 241117A
  89. GRB 241026A: VIRT Optical Upper Limit
  90. GRB 241025A: VIRT Optical Upper Limit
  91. Konus-Wind detection of GRB 241120A
  92. GRB241120A: OHP/T193 optical observations
  93. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  94. GRB 241120A: Mondy and AbAO optical observations
  95. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  96. GRB 241113A: Possible ATCA Radio detection
  97. GRB 241114B: Insight-HXMT/HE detection
  98. EP241119a: EP detection of a fast X-ray transient
  99. GRB 241120A: Fermi GBM Final Real-time Localization
  100. GRB 241115A: CALET Gamma-Ray Burst Monitor detection

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