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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"

14845 results found.

  1. Konus-Wind detection of GRB 241213A (EP 241213a)
  2. GRB 241214A: SVOM/GRM observation
  3. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  4. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  5. GRB 241212A: Fermi GBM detection
  6. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  7. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  8. GRB 241213B: MAXI/GSC detection
  9. EP241213a: EP detection of An X-ray Transient
  10. GRB241212A: OHP/T193 optical observations
  11. GRB 241213A: Swift detection of a burst
  12. GRB 241212A: AstroSat CZTI detection
  13. GRB 241212A: SVOM detection of a bright long burst
  14. GRB 241212A: Fermi GBM Final Real-time Localization
  15. GRB 241209A: Chandra X-ray Detection
  16. Konus-Wind detection of GRB 241209B
  17. GRB 241207A: EIRSAT-1 GMOD Detection
  18. GRB 241209B: GRBAlpha detection
  19. GRB 241206C: GRBAlpha detection
  20. GRB 241211A: Fermi GBM Final Real-time Localization
  21. Konus-Wind detection of GRB 241209D
  22. GRB 241209B: Swift-XRT afterglow detection
  23. GRB 241209D: AstroSat CZTI detection
  24. GRB 241209B: SVOM/VT afterglow detection
  25. EP241208a: EP-FXT follow-up observations
  26. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  27. GRB 241209D: COLIBRÍ detection of the afterglow
  28. GRB 241209B: BOOTES-5 optical upper limit
  29. GRB 241209E: Fermi GBM Final Real-time Localization
  30. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  31. GRB 241209C: AstroSat CZTI detection
  32. GRB 241209D: Swift detection of a burst
  33. GRB 241209D: Fermi GBM Final Real-time Localization
  34. GRB 241114B: cubesat Avion detection
  35. GRB 241209C: Fermi GBM Final Real-time Localization
  36. EP241206a: 1.5m OSN optical limit
  37. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  38. EP241208a: EP detection of a fast X-ray transient
  39. GRB 241209A: Swift detection of a short burst
  40. GRB 241209A: Fermi GBM Final Real-time Localization
  41. GRB 241201A: AstroSat CZTI detection
  42. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  43. EP241206a: BOOTES Global Network optical limits
  44. GRB 241207C: MAXI/GSC detection
  45. GRB 241207B: Fermi GBM Final Real-time Localization
  46. EP241206a: EP detection of a fast X-ray transient
  47. GRB 241206C: SVOM/GRM observation of a likely short burst
  48. GRB 241207A: Fermi GBM Final Real-time Localization
  49. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  50. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  51. GRB 241206A: Fermi GBM Final Real-time Localization
  52. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  53. GRB 241201A: GRBAlpha detection
  54. GRB 241204A: Fermi-LAT detection
  55. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  56. EP241202b: Kinder optical counterpart candidate
  57. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  58. EP241201a: EP-FXT follow-up observations
  59. Konus-Wind detection of GRB 241130A
  60. EP241201a: BOOTES-5 optical upper limit
  61. EP241202b: EP detection of a fast X-ray transient
  62. IPN triangulation of GRB 241130A
  63. GRB 241130A: EIRSAT-1 GMOD Detection
  64. GRB 241130A: Fermi GBM Detection
  65. EP241201a: Kinder optical counterpart candidate
  66. EP241201a: EP detection of a fast X-ray transient
  67. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  68. GRB241201B: Fermi GBM Final Localization
  69. GRB241201B: Fermi GBM Final Localization
  70. GRB 241130A: Fermi GBM Final Real-time Localization
  71. GRB 241130A: Fermi GBM Final Real-time Localization
  72. GRB 241201A: Fermi GBM Final Real-time Localization
  73. IPN triangulation of GRB 241128B
  74. Konus-Wind detection of GRB 241114B
  75. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  76. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  77. GRB 241128C: SVOM/GRM observation
  78. GRB 241128B: SVOM/GRM observation
  79. GRB 241127A: PRIME near-infrared detection
  80. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  81. Swift-XRT observations of IceCube -241127A
  82. GRB 241129A: Fermi GBM Final Real-time Localization
  83. GRB 241128A: LCO optical detection
  84. GRB 241128A: 1.5m OSN optical afterglow detection
  85. GRB 241128A: Swift-XRT afterglow detection
  86. GRB 241128A: Swift detection of a burst
  87. GRB 241127A: Swift/UVOT Detection
  88. GRB 241127A: SVOM/GRM observation
  89. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  90. Swift GRB241127.91: Global MASTER-Net OT detection
  91. EP241126a: WFST Observations
  92. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  93. GRB 241127A: Swift detection of a burst with an optical counterpart
  94. Swift GRB241127.91: Global MASTER-Net OT detection
  95. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  96. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  97. EP241126a: Optical Upper limits with Kinder observations
  98. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  99. GRB 241126A: SVOM/GRM observation
  100. IPN triangulation of GRB 241114B

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