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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').
Advanced Search

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"

32686 results found.

  1. GRB 260112B: GECAM-B observation
  2. GRB 260114A: GMG Optical Observation
  3. Fermi-LAT Gamma-ray Observations of IceCube-260111A
  4. EP-WXT trigger 01709251266: SVOM/C-GFT confirmation of a stellar flare
  5. IceCube-260111A: Upper limits from a search for additional neutrino events in IceCube
  6. EP260110a: NOT and GTC Optical and Near-Infrared Observations
  7. EP260110a: TRT optical upper limits
  8. Konus-Wind detection of GRB 260101A
  9. GRB 260111A: Swift-XRT observations
  10. GRB 260111A: COLIBRÍ optical afterglow candidate
  11. GRB 260111A: GECAM-B observation of a burst
  12. GRB 260111A: Fermi GBM Observation
  13. Swift Trigger 1434591 is not a GRB
  14. GRB 260111A: GOTO optical upper limits
  15. GRB 260111A: Swift ToO observations
  16. GRB 251230A: Mondy Optical Observations
  17. GRB 260111A: Swift/BAT-GUANO arcminute localization of a burst
  18. EP260110a: SVOM/VT optical upper limits
  19. EP260110a: Global MASTER-Net observations report
  20. Fermi GRB 260111A: Global MASTER-Net observations report
  21. EP260110a: KAIT optical upper limit
  22. EP260110a: refined analysis of the EP-WXT and EP-FXT observations
  23. EP 260110a: COLIBRÍ optical observations
  24. EP260110a: SVOM/C-GFT upper limit
  25. EP260110a: BOOTES-5/JGU optical upper limit
  26. GRB 260109C: LCO optical upper limits
  27. GRB 260109C: Kilonova-Catcher optical upper limit
  28. EP260105b / GRB 260105C : Fermi-GBM Sub-Threshold Detection
  29. GRB 260104A: Swift-BAT refined analysis
  30. GRB 260101A: Swift-BAT refined analysis
  31. Swift GRB 251230A: Global MASTER-Net OT detection
  32. Fermi GRB 260107A: Global MASTER-Net observations report
  33. GRB 260102A: AbAO optical observations
  34. EP260105b/EP-WXT trigger 01709251028: Einstein Probe detection of an X-ray transient
  35. Fermi GRB 260105A: Global MASTER-Net observations report
  36. EP260105a: FTW optical observations
  37. EP260104a: FTW optical observations
  38. GRB 260105A: SVOM/GRM observation
  39. GRB 260105B: SVOM/GRM observation
  40. FRB 20251229A: COLIBRÍ optical upper limits
  41. Fermi GRB 260105B: Global MASTER-Net observations report
  42. EP260105a: SVOM/VT optical upperlimit
  43. EP260105a: refined analysis of the EP-WXT and EP-FXT observations
  44. EP260105a: LCO Optical Upper limit
  45. EP260104a: Global MASTER-Net observations report
  46. GRB 260101A: COLIBRÍ optical upper limits
  47. EP260105a: Global MASTER-Net observations report
  48. GRB 260103A: Insight-HXMT/HE detection
  49. GRB 260104A: COLIBRÍ optical upper limits
  50. Fermi GRB 260104B: Global MASTER-Net observations report
  51. Swift GRB 260104A: Global MASTER-Net observations report
  52. GRB 251230A/EP-WXT trigger 01709250693: Mephisto optical upper limits
  53. GRB 260101A: Swift/UVOT Detection
  54. GRB 260103A: GECAM-B observation of a burst
  55. Fermi-LAT Gamma-ray Observations of IceCube-251225A
  56. GRB 260101A: COLIBRÍ optical observations
  57. Fermi GBM Sub-Threshold Detection of GRB 260102A
  58. GRB 260102A: EP-FXT follow-up observation
  59. EP260101a: Global MASTER-Net observations report
  60. GRB 260102A: LCO optical upper limits
  61. GRB 260102A: Swift-XRT observations
  62. GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations
  63. GRB 251230A / EP251230a: GECAM-B detection
  64. GRB 260102A: SVOM/VT optical counterpart
  65. GRB 251230A / EP251230a: Insight-HXMT/HE detection
  66. GRB 260102A: Swift ToO observations
  67. GRB 260101A: Fermi GBM Observation
  68. EP260101a: refined analysis of the EP-WXT and EP-FXT observations
  69. GRB 260101A: GECAM-B detection
  70. GRB 260101A: NOT spectroscopic observations
  71. GRB 260101A: SVOM/GRM observation
  72. Swift GRB 260101A: Global MASTER-Net observations report
  73. GRB 260101A: OSIRIS+ redshift z = 2.623 for the new year burst
  74. GRB 260101A: LCO detection of the optical counterpart
  75. GRB 251230A / EP251230a: SVOM/VT optical continued observations and upper limit
  76. GRB 251230A: GRANDMA/TAROT Early Detection
  77. GRB 251230A / EP251230a: further NOT optical observations revealing shallower decay or possible rebrightening
  78. GRB 251230A/EP251230a: Optical upper limit with Kinder observations
  79. EP251229a: Optical upper limit with Kinder observations
  80. GRB 251230A: 1.3m DFOT optical upper limit
  81. GRB 251222A: Mondy Optical Observations
  82. EP251230a / GRB 251230A: refined analysis of the EP-WXT and EP-FXT observations
  83. GRB 251230A: Swift/UVOT detection
  84. GRB251230A: 7DT optical upper limits
  85. GRB 251230A / EP251230a: NOT observations and spectroscopic redshift upper limit z < 2.2
  86. EP251229a: BOOTES-2 early optical upper limit
  87. GRB 251230A: GOTO optical upper limit
  88. EP251229a: NOT optical upper limits
  89. GRB 251230A / EP251230a: SVOM/VT optical observation
  90. EP251229a: refined analysis of the EP-WXT and EP-FXT observations
  91. GRB 251230A: Early optical counterpart detection by LCO.
  92. EP-WXT trigger 01709250662 Mephisto and 50cm telescope follow-up
  93. GRB 251230A: Optical Observations via Virtual Telescope Project, Italy
  94. EP251230a / GRB 251230A: Einstein Probe detection of an X-ray transient
  95. GRB 251230A/EP#01709250693 (likely EP251230a): FTW optical and NIR observations
  96. LIGO/Virgo/KAGRA S251112cm: Candidates from the NSF-DOE Vera C. Rubin Observatory
  97. Swift GRB 251230A: Global MASTER-Net observations report
  98. The EP-WXT trigger 01709250693/GRB 251230A: Las Cumbres detection of the optical counterpart
  99. EP251229a: Global MASTER-Net observations report
  100. GRB 251226A: Glowbug gamma-ray detection

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