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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"

14863 results found.

  1. EP 241217a: Possible J-band detection with WINTER
  2. GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
  3. EP241217a: Liverpool Telescope optical follow-up
  4. EP241119a: 7DT Optical upper limits
  5. GRB 241209A: ATCA radio follow-up observations
  6. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  7. GRB 241218A: Swift detection of a burst
  8. GRB 241217A : SVOM/VT optical afterglow detection
  9. GRB 241217A: Swift-XRT afterglow detection
  10. EP241217a: Swift-XRT Detection
  11. EP241217A: Non-detection from Fermi-GBM Observations
  12. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  13. EP241217a: Gemini-North spectroscopic redshift z = 4.59
  14. GRB 241214A: GRBAlpha detection
  15. GRB 241213A (EP241213a): GRBAlpha detection
  16. GRB 241209D: GRBAlpha detection
  17. EP241217a: Gemini-North detection of the likely optical counterpart
  18. EP241217a: EP detection of an X-ray transient
  19. Konus-Wind detection of GRB 241213A (EP 241213a)
  20. GRB 241214A: SVOM/GRM observation
  21. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  22. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  23. GRB 241212A: Fermi GBM detection
  24. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  25. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  26. GRB 241213B: MAXI/GSC detection
  27. EP241213a: EP detection of An X-ray Transient
  28. GRB241212A: OHP/T193 optical observations
  29. GRB 241213A: Swift detection of a burst
  30. GRB 241212A: AstroSat CZTI detection
  31. GRB 241212A: SVOM detection of a bright long burst
  32. GRB 241212A: Fermi GBM Final Real-time Localization
  33. GRB 241209A: Chandra X-ray Detection
  34. Konus-Wind detection of GRB 241209B
  35. GRB 241207A: EIRSAT-1 GMOD Detection
  36. GRB 241209B: GRBAlpha detection
  37. GRB 241206C: GRBAlpha detection
  38. GRB 241211A: Fermi GBM Final Real-time Localization
  39. Konus-Wind detection of GRB 241209D
  40. GRB 241209B: Swift-XRT afterglow detection
  41. GRB 241209D: AstroSat CZTI detection
  42. GRB 241209B: SVOM/VT afterglow detection
  43. EP241208a: EP-FXT follow-up observations
  44. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  45. GRB 241209D: COLIBRÍ detection of the afterglow
  46. GRB 241209B: BOOTES-5 optical upper limit
  47. GRB 241209E: Fermi GBM Final Real-time Localization
  48. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  49. GRB 241209C: AstroSat CZTI detection
  50. GRB 241209D: Swift detection of a burst
  51. GRB 241209D: Fermi GBM Final Real-time Localization
  52. GRB 241114B: cubesat Avion detection
  53. GRB 241209C: Fermi GBM Final Real-time Localization
  54. EP241206a: 1.5m OSN optical limit
  55. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  56. EP241208a: EP detection of a fast X-ray transient
  57. GRB 241209A: Swift detection of a short burst
  58. GRB 241209A: Fermi GBM Final Real-time Localization
  59. GRB 241201A: AstroSat CZTI detection
  60. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  61. EP241206a: BOOTES Global Network optical limits
  62. GRB 241207C: MAXI/GSC detection
  63. GRB 241207B: Fermi GBM Final Real-time Localization
  64. EP241206a: EP detection of a fast X-ray transient
  65. GRB 241206C: SVOM/GRM observation of a likely short burst
  66. GRB 241207A: Fermi GBM Final Real-time Localization
  67. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  68. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  69. GRB 241206A: Fermi GBM Final Real-time Localization
  70. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  71. GRB 241201A: GRBAlpha detection
  72. GRB 241204A: Fermi-LAT detection
  73. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  74. EP241202b: Kinder optical counterpart candidate
  75. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  76. EP241201a: EP-FXT follow-up observations
  77. Konus-Wind detection of GRB 241130A
  78. EP241201a: BOOTES-5 optical upper limit
  79. EP241202b: EP detection of a fast X-ray transient
  80. IPN triangulation of GRB 241130A
  81. GRB 241130A: EIRSAT-1 GMOD Detection
  82. GRB 241130A: Fermi GBM Detection
  83. EP241201a: Kinder optical counterpart candidate
  84. EP241201a: EP detection of a fast X-ray transient
  85. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  86. GRB241201B: Fermi GBM Final Localization
  87. GRB241201B: Fermi GBM Final Localization
  88. GRB 241130A: Fermi GBM Final Real-time Localization
  89. GRB 241130A: Fermi GBM Final Real-time Localization
  90. GRB 241201A: Fermi GBM Final Real-time Localization
  91. IPN triangulation of GRB 241128B
  92. Konus-Wind detection of GRB 241114B
  93. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  94. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  95. GRB 241128C: SVOM/GRM observation
  96. GRB 241128B: SVOM/GRM observation
  97. GRB 241127A: PRIME near-infrared detection
  98. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  99. Swift-XRT observations of IceCube -241127A
  100. GRB 241129A: Fermi GBM Final Real-time Localization

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