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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"

28233 results found.

  1. GRB 251226A: GECAM-B detection
  2. SVOM GRB251227.07: Global MASTER-Net observations report
  3. IceCube-251225A: Upper limits from a search for additional neutrino events in IceCube
  4. IceCube Alert 251225.84: Global MASTER-Net observations report
  5. GRB 251222A/EP251222b: Optical detection with Kinder observations
  6. EP251222a: Optical upper limit with Kinder observations
  7. GRB 251221A: Swift-BAT refined analysis
  8. GRB 251205A: Kilonova-Catcher optical afterglow detection
  9. GRB 251222A: AbAO optical observations
  10. GRB 251222A / EP251222b: Kilonova-Catcher optical afterglow detection
  11. GRB 251222A: ZTSH BVRI optical observations
  12. GRB 251222A: SVOM/COLIBRÍ (FM-GFT) optical observations
  13. GRB 251222A: Continued 1.3m DFOT optical observation
  14. EP251220a: 3.6m DOT optical afterglow detection
  15. GRB 251222A: Fermi GBM Observation
  16. EP251220a: CrAO ZTSh optical observations
  17. EP251221a: PRIME upper limit
  18. EP251222a: Global MASTER-Net observations report
  19. EP251221a: Liverpool Telescope upper limits
  20. EP251222a: refined analysis of the EP-WXT and EP-FXT observations
  21. EP251222b/GRB 251222A: refined analysis of the EP-WXT and EP-FXT observations
  22. GRB 251222A: Swift-XRT afterglow detection
  23. GRB 251222A / EP251222b: LCO detection of the optical counterpart
  24. EP251222a: NTT/ULTRACAM optical observations
  25. GRB 251222A / EP251222b: GOTO optical counterpart detection
  26. GRB 251222A / EP251222b: LCO optical observations
  27. GRB 251222A: 1.3m DFOT optical detection
  28. GRB251221A: 7DT optical upper limits
  29. EP251222a: GSP Optical Counterpart Detection
  30. EP251222b/GRB 251222A: Einstein Probe detection of an X-ray transient
  31. EP251222a: Einstein Probe detection of an X-ray transient
  32. EP251221a: Global MASTER-Net observations report
  33. GRB 251222A: PRIME near-infrared detection
  34. EP251221a: NOT optical upper limit
  35. GRB 251222A: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  36. IceCube-251218A: No Candidate Transients from the Zwicky Transient Facility
  37. IPN triangulation of GRB 251220B (short)
  38. GRB 251222A: BALROG localization (Fermi Trigger / GRB 251222712)
  39. GRB 251222A: SVOM/VT optical candidate
  40. GRB 251222A: SVOM detection of a long burst
  41. SVOM GRB251222A: Global MASTER-Net observations report
  42. EP251220a: PRIME upper limit
  43. GRB 251221A: PRIME near-infrared observation
  44. GRB 251221A: UAFO and Mondy optical upper limit
  45. GRB 251221A: Swift-XRT refined Analysis
  46. EP251221a: Einstein Probe detection of a fast X-ray transient
  47. GRB 251221A: Swift/UVOT Upper Limits
  48. GRB 251221A: Enhanced Swift-XRT position
  49. GRB 251221A: Fermi GBM Observation
  50. GRB 251220B: SVOM/GRM observation of a short burst
  51. EP251220a: COLIBRÍ confirmation of fading and photometric redshift upper limit of z < 3.4
  52. EP 251220a: GOTO optical counterpart detection
  53. GRB 251221A: COLIBRÍ detection of the optical counterpart
  54. EP 251220a: COLIBRÍ detection of the optical counterpart
  55. GRB 251221A: Swift detection of a burst
  56. Swift GRB251221A: Global MASTER-Net observations report
  57. EP251220a: Global MASTER-Net observations report
  58. EP251220a: EP detection of a fast X-ray transient
  59. SVOM GRB251220.98: Global MASTER-Net observations report
  60. GRB 251219A: SVOM/GRM observation of a short burst
  61. GRB 251219A: GECAM-B detection of a possible magnetar X-ray burst from SGR 1830-0645
  62. Fermi-LAT Gamma-ray Observations of IceCube-251218A
  63. GRB 251220A: MAXI/GSC detection
  64. GRB 251215A: Swift-XRT afterglow detection
  65. IceCube-251218A: Upper limits from a search for additional neutrino events in IceCube
  66. IceCube-251218A: COLIBRÍ optical upper limits
  67. SVOM GRB251219.11: Global MASTER-Net observations report
  68. IceCube Alert 251218.85: Global MASTER-Net observations report
  69. GRB 251214B: VIRT Optical Upper Limit
  70. Fermi trigger No 787736968: Global MASTER-Net observations report
  71. Fermi GRB 251217A: Global MASTER-Net observations report
  72. GRB 251215A: Swift/UVOT Upper LImits
  73. GRB 251215A: Fermi GBM Observation
  74. Fermi GRB 251216A: Global MASTER-Net observations report
  75. GRB 251202A/EP251202a: Koshka optical upper limit
  76. GRB 251214B: Mondy optical upper limit
  77. GRB 251215A: COLIBRÍ optical upper limit
  78. EP251214b: KAIT optical upper limit
  79. GRB 251215A: Swift-XRT observations
  80. Fermi GRB 251215A: Global MASTER-Net observations report
  81. EP251214a: Optical upper limit with Kinder observations
  82. GRB 251214B: 1.6m Mephisto observations with newly installed mosaic cameras
  83. GRB 251215A: Glowbug gamma-ray detection
  84. GRB 251214B: UAFO optical upper limit
  85. GRB 251214B: VLT/X-shooter observations
  86. GRB 251214B: Swift-BAT refined analysis
  87. GRB 251202A: radio detection with the VLA
  88. EP251214b: Global MASTER-Net observations report
  89. EP251214b : Einstein Probe detection of a fast X-ray transient
  90. EP251214b : Einstein Probe detection of a fast X-ray transient
  91. GRB 251214B: AbAO optical observations
  92. GRB 251214B: LCO detection of the optical counterpart
  93. GRB 251214B: Fermi GBM Observation
  94. EP251214b (EP trigger 01709250023): LCO optical limits
  95. GRB 251203B: AbAO optical observations
  96. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  97. GRB 251214B: Swift-XRT refined Analysis
  98. GRB 251213A: SVOM/GRM observation
  99. EP251214a: KAIT optical upper limit
  100. GRB 251213A: AstroSat CZTI detection

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