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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"

28291 results found.

  1. Fermi GRB 260104B: Global MASTER-Net observations report
  2. Swift GRB 260104A: Global MASTER-Net observations report
  3. GRB 251230A/EP-WXT trigger 01709250693: Mephisto optical upper limits
  4. GRB 260104A: Swift-XRT refined Analysis
  5. GRB 260104A: Enhanced Swift-XRT position
  6. GRB 260101A: Swift/UVOT Detection
  7. GRB 260103A: GECAM-B observation of a burst
  8. GRB 260104A: Swift detection of a burst
  9. Fermi-LAT Gamma-ray Observations of IceCube-251225A
  10. GRB 260101A: COLIBRÍ optical observations
  11. SVOM GRB260103.08: Global MASTER-Net observations report
  12. SVOM GRB260102A: Global MASTER-Net observations report
  13. Fermi GBM Sub-Threshold Detection of GRB 260102A
  14. GRB 260102A: EP-FXT follow-up observation
  15. EP260101a: Global MASTER-Net observations report
  16. GRB 260102A: LCO optical upper limits
  17. GRB 260102A: Swift-XRT observations
  18. GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations
  19. GRB 260101A: Fermi GBM Observation
  20. EP260101a: refined analysis of the EP-WXT and EP-FXT observations
  21. GRB 260102A: SVOM detection of a burst
  22. GRB 260101A: NOT spectroscopic observations
  23. GRB 260101A: SVOM/GRM observation
  24. GRB 260101A: Swift-XRT refined Analysis
  25. Swift GRB 260101A: Global MASTER-Net observations report
  26. GRB 260101A: Enhanced Swift-XRT position
  27. EP260101a: Einstein Probe detection of an X-ray transient
  28. GRB 260101A: LCO detection of the optical counterpart
  29. GRB 260101A: Swift detection of a burst with an optical counterpart
  30. GRB 260101A: Fermi GBM Final Real-time Localization
  31. SVOM GRB251231.57: Global MASTER-Net observations report
  32. GRB 251230A: GRANDMA/TAROT Early Detection
  33. GRB 251230A/EP251230a: Optical upper limit with Kinder observations
  34. EP251229a: Optical upper limit with Kinder observations
  35. GRB 251230A: 1.3m DFOT optical upper limit
  36. GRB 251230A: Swift-XRT refined Analysis
  37. GRB 251222A: Mondy Optical Observations
  38. EP251230a / GRB 251230A: refined analysis of the EP-WXT and EP-FXT observations
  39. GRB 251230A: Swift/UVOT detection
  40. GRB251230A: 7DT optical upper limits
  41. GRB 251230A: GOTO optical upper limit
  42. EP251229a: NOT optical upper limits
  43. GRB 251230A / EP251230a: SVOM/VT optical observation
  44. EP251229a: refined analysis of the EP-WXT and EP-FXT observations
  45. GRB 251230A: Enhanced Swift-XRT position
  46. GRB 251230A: Early optical counterpart detection by LCO.
  47. EP-WXT trigger 01709250662 Mephisto and 50cm telescope follow-up
  48. EP251230a / GRB 251230A: Einstein Probe detection of an X-ray transient
  49. LIGO/Virgo/KAGRA S251112cm: Candidates from the NSF-DOE Vera C. Rubin Observatory
  50. Swift GRB 251230A: Global MASTER-Net observations report
  51. EP251229a: Global MASTER-Net observations report
  52. EP251229a: Einstein Probe detection of an X-ray transient
  53. GRB 251230A: Swift detection of a burst with a bright optical counterpart
  54. GRB 251226A: Glowbug gamma-ray detection
  55. GRB 251222A/EP251222b: 1.6m Mephisto optical followup
  56. Fermi GRB 251228A: Global MASTER-Net observations report
  57. GRB 251226A: SVOM/GRM observation
  58. GRB 251226A: GECAM-B detection
  59. SVOM GRB251227.07: Global MASTER-Net observations report
  60. IceCube-251225A: Upper limits from a search for additional neutrino events in IceCube
  61. IceCube Alert 251225.84: Global MASTER-Net observations report
  62. GRB 251222A/EP251222b: Optical detection with Kinder observations
  63. EP251222a: Optical upper limit with Kinder observations
  64. GRB 251221A: Swift-BAT refined analysis
  65. GRB 251205A: Kilonova-Catcher optical afterglow detection
  66. GRB 251222A: AbAO optical observations
  67. GRB 251222A / EP251222b: Kilonova-Catcher optical afterglow detection
  68. GRB 251222A: ZTSH BVRI optical observations
  69. GRB 251222A: SVOM/COLIBRÍ (FM-GFT) optical observations
  70. GRB 251222A: Continued 1.3m DFOT optical observation
  71. EP251220a: 3.6m DOT optical afterglow detection
  72. GRB 251222A: Fermi GBM Observation
  73. EP251220a: CrAO ZTSh optical observations
  74. EP251221a: PRIME upper limit
  75. EP251222a: Global MASTER-Net observations report
  76. EP251221a: Liverpool Telescope upper limits
  77. EP251222a: refined analysis of the EP-WXT and EP-FXT observations
  78. EP251222b/GRB 251222A: refined analysis of the EP-WXT and EP-FXT observations
  79. GRB 251222A: Swift-XRT afterglow detection
  80. GRB 251222A / EP251222b: LCO detection of the optical counterpart
  81. EP251222a: NTT/ULTRACAM optical observations
  82. GRB 251222A / EP251222b: GOTO optical counterpart detection
  83. GRB 251222A / EP251222b: LCO optical observations
  84. GRB 251222A: 1.3m DFOT optical detection
  85. GRB251221A: 7DT optical upper limits
  86. EP251222a: GSP Optical Counterpart Detection
  87. EP251222b/GRB 251222A: Einstein Probe detection of an X-ray transient
  88. EP251222a: Einstein Probe detection of an X-ray transient
  89. EP251221a: Global MASTER-Net observations report
  90. GRB 251222A: PRIME near-infrared detection
  91. EP251221a: NOT optical upper limit
  92. GRB 251222A: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  93. IceCube-251218A: No Candidate Transients from the Zwicky Transient Facility
  94. IPN triangulation of GRB 251220B (short)
  95. GRB 251222A: BALROG localization (Fermi Trigger / GRB 251222712)
  96. GRB 251222A: SVOM/VT optical candidate
  97. GRB 251222A: SVOM detection of a long burst
  98. SVOM GRB251222A: Global MASTER-Net observations report
  99. EP251220a: PRIME upper limit
  100. GRB 251221A: PRIME near-infrared observation

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