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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"

28253 results found.

  1. Fermi GRB 260115A: Global MASTER-Net observations report
  2. GRB 251222A: radio detection with the VLA
  3. GRB 260114A: VLT/HAWK-I near-infrared upper limits
  4. GRB 260114A: Swift-XRT refined Analysis
  5. GRB 260114A: VLT/X-shooter redshift of the putative host galaxy
  6. GRB 260114A : MITSuME Akeno optical upper limits
  7. GRB 260114A: COLIBRÍ optical upper limits
  8. GRB 260114A: TNG NIR upper limit
  9. GRB 260114A: NOT optical observations
  10. GRB 260114A: SVOM/GRM observation of a short burst
  11. Swift GRB 260114A: Global MASTER-Net observations report
  12. GRB 260114A: Mondy optical observations
  13. GRB 260114A: GMG Optical Observation
  14. Fermi-LAT Gamma-ray Observations of IceCube-260111A
  15. GRB 260114A: Swift detection of a short burst
  16. EP-WXT trigger 01709251266: SVOM/C-GFT confirmation of a stellar flare
  17. IceCube-260111A: Upper limits from a search for additional neutrino events in IceCube
  18. Swift GRB260113.43: Global MASTER-Net observations report
  19. EP260110a: NOT and GTC Optical and Near-Infrared Observations
  20. EP260110a: TRT optical upper limits
  21. Konus-Wind detection of GRB 260101A
  22. GRB 260111A: Swift-XRT observations
  23. Swift Trigger 1439093: is probably not GRB 260113A
  24. GRB 260111A: COLIBRÍ optical afterglow candidate
  25. GRB 260111A: Fermi GBM Observation
  26. GRB 251230A: Mondy Optical Observations
  27. GRB 260111A: Swift/BAT-GUANO arcminute localization of a burst
  28. IceCube Alert 260111A: Global MASTER-Net observations report
  29. EP260110a: Global MASTER-Net observations report
  30. Fermi GRB 260111A: Global MASTER-Net observations report
  31. Swift trigger 1436759 is not an astrophysical event
  32. EP260110a: KAIT optical upper limit
  33. EP260110a: refined analysis of the EP-WXT and EP-FXT observations
  34. EP 260110a: COLIBRÍ optical observations
  35. EP260110a: SVOM/C-GFT upper limit
  36. EP260110a: Einstein Probe detection of an X-ray transient
  37. GRB 260109C: LCO optical upper limits
  38. GRB 260109C: Kilonova-Catcher optical upper limit
  39. EP260105b / GRB 260105C : Fermi-GBM Sub-Threshold Detection
  40. Swift Trigger 1434591: possible GRB 260109C
  41. GRB 260102A: Swift-XRT afterglow detection
  42. GRB 260104A: Swift-BAT refined analysis
  43. GRB 260101A: Swift-BAT refined analysis
  44. Swift GRB 251230A: Global MASTER-Net OT detection
  45. Fermi GRB 260107A: Global MASTER-Net observations report
  46. GRB 260102A: AbAO optical observations
  47. EP260105b/EP-WXT trigger 01709251028: Einstein Probe detection of an X-ray transient
  48. Fermi GRB 260105A: Global MASTER-Net observations report
  49. GRB 260105B: Fermi GBM Detection
  50. GRB 260105B: BALROG localization (Fermi Trigger 789348101 / GRB 260105973)
  51. GRB 260105A: SVOM/GRM observation
  52. GRB 260105B: SVOM/GRM observation
  53. FRB 20251229A: COLIBRÍ optical upper limits
  54. Fermi GRB 260105B: Global MASTER-Net observations report
  55. FRB 20251229A: A potentially hyperactive repeating fast radio burst source
  56. EP260105a: refined analysis of the EP-WXT and EP-FXT observations
  57. EP260105a: LCO Optical Upper limit
  58. EP260104a: Global MASTER-Net observations report
  59. EP260104a: Einstein Probe detection of a fast X-ray transient
  60. GRB 260101A: COLIBRÍ optical upper limits
  61. EP260105a: Global MASTER-Net observations report
  62. EP260105a: Einstein Probe detection of an X-ray transient
  63. GRB 260104A: COLIBRÍ optical upper limits
  64. Fermi GRB 260104B: Global MASTER-Net observations report
  65. Swift GRB 260104A: Global MASTER-Net observations report
  66. GRB 251230A/EP-WXT trigger 01709250693: Mephisto optical upper limits
  67. GRB 260104A: Swift-XRT refined Analysis
  68. GRB 260104A: Enhanced Swift-XRT position
  69. GRB 260101A: Swift/UVOT Detection
  70. GRB 260103A: GECAM-B observation of a burst
  71. GRB 260104A: Swift detection of a burst
  72. Fermi-LAT Gamma-ray Observations of IceCube-251225A
  73. GRB 260101A: COLIBRÍ optical observations
  74. SVOM GRB260103.08: Global MASTER-Net observations report
  75. SVOM GRB260102A: Global MASTER-Net observations report
  76. Fermi GBM Sub-Threshold Detection of GRB 260102A
  77. GRB 260102A: EP-FXT follow-up observation
  78. EP260101a: Global MASTER-Net observations report
  79. GRB 260102A: LCO optical upper limits
  80. GRB 260102A: Swift-XRT observations
  81. GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations
  82. GRB 260101A: Fermi GBM Observation
  83. EP260101a: refined analysis of the EP-WXT and EP-FXT observations
  84. GRB 260102A: SVOM detection of a burst
  85. GRB 260101A: NOT spectroscopic observations
  86. GRB 260101A: SVOM/GRM observation
  87. GRB 260101A: Swift-XRT refined Analysis
  88. Swift GRB 260101A: Global MASTER-Net observations report
  89. GRB 260101A: Enhanced Swift-XRT position
  90. EP260101a: Einstein Probe detection of an X-ray transient
  91. GRB 260101A: LCO detection of the optical counterpart
  92. GRB 260101A: Swift detection of a burst with an optical counterpart
  93. GRB 260101A: Fermi GBM Final Real-time Localization
  94. SVOM GRB251231.57: Global MASTER-Net observations report
  95. GRB 251230A: GRANDMA/TAROT Early Detection
  96. GRB 251230A/EP251230a: Optical upper limit with Kinder observations
  97. EP251229a: Optical upper limit with Kinder observations
  98. GRB 251230A: 1.3m DFOT optical upper limit
  99. GRB 251230A: Swift-XRT refined Analysis
  100. GRB 251222A: Mondy Optical Observations

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