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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"

32689 results found.

  1. EP251229a: Global MASTER-Net observations report
  2. GRB 251226A: Glowbug gamma-ray detection
  3. GRB 251222A/EP251222b: 1.6m Mephisto optical followup
  4. GRB 251129A: redshift correction and SN detection at z = 0.505 with GTC
  5. Fermi GRB 251228A: Global MASTER-Net observations report
  6. GRB 251226A: SVOM/GRM observation
  7. IceCube-251225A: Upper limits from a search for additional neutrino events in IceCube
  8. GRB 251222A: NUTTelA-TAO Early Measurements
  9. GRB 251222A/EP251222b: Optical detection with Kinder observations
  10. EP251222a: Optical upper limit with Kinder observations
  11. GRB 251221A: Swift-BAT refined analysis
  12. GRB 251222A/EP251222b: FTW optical and NIR observations
  13. EP251222a: FTW optical and NIR observations
  14. GRB 251205A: Kilonova-Catcher optical afterglow detection
  15. GRB 251222A: AbAO optical observations
  16. GRB 251222A / EP251222b: Kilonova-Catcher optical afterglow detection
  17. GRB 251129A / EP251129a: VLA detection of a radio counterpart
  18. EP251222a: VLT/FORS2 spectroscopic redshift z = 0.505
  19. GRB 251222A: ZTSH BVRI optical observations
  20. GRB 251222A: SVOM/COLIBRÍ (FM-GFT) optical observations
  21. GRB 251222A: Continued 1.3m DFOT optical observation
  22. EP251220a: 3.6m DOT optical afterglow detection
  23. GRB 251222A: Fermi GBM Observation
  24. EP251220a: CrAO ZTSh optical observations
  25. EP251221a: PRIME upper limit
  26. EP251222a: Global MASTER-Net observations report
  27. GRB 251222A / EP251222b: GECAM-B observation
  28. EP251221a: Liverpool Telescope upper limits
  29. EP251222a: refined analysis of the EP-WXT and EP-FXT observations
  30. EP251222b/GRB 251222A: refined analysis of the EP-WXT and EP-FXT observations
  31. Konus-Wind detection of GRB 251222A / EP251222b
  32. GRB 251222A / EP251222b: LCO detection of the optical counterpart
  33. EP251222a: NTT/ULTRACAM optical observations
  34. EP251222a: GOTO optical upper limit
  35. GRB 251222A / EP251222b: GOTO optical counterpart detection
  36. GRB 251222A / EP251222b: LCO optical observations
  37. GRB 251222A: 1.3m DFOT optical detection
  38. GRB251221A: 7DT optical upper limits
  39. EP251222a: GSP Optical Counterpart Detection
  40. GRB 251222A / EP251222b: VLT/X-shooter spectroscopic redshift z = 3.171
  41. GRB 251222A / EP251222b: SVOM/VT optical rebrightening
  42. EP251222b/GRB 251222A: SVOM/GRM observation
  43. EP251222b/GRB 251222A: Einstein Probe detection of an X-ray transient
  44. EP251221a: Global MASTER-Net observations report
  45. GRB 251222A: PRIME near-infrared detection
  46. EP251221a: NOT optical upper limit
  47. GRB 251222A: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  48. GRB 251222A: NOT optical observations
  49. IceCube-251218A: No Candidate Transients from the Zwicky Transient Facility
  50. IPN triangulation of GRB 251220B (short)
  51. GRB 251222A: Swift ToO observations
  52. GRB 251222A: SVOM/VT optical candidate
  53. GRB 251222A: SVOM detection of a long burst
  54. EP251220a: PRIME upper limit
  55. EP251220a: VLT/FORS2 spectroscopic redshift z = 2.375
  56. GRB 251221A: PRIME near-infrared observation
  57. EP251220a: NOT optical observations
  58. EP251220a: FTW optical and NIR observations
  59. GRB 251221A: UAFO and Mondy optical upper limit
  60. GRB 251221A: Swift/UVOT Upper Limits
  61. GRB 251221A: Fermi GBM Observation
  62. EP251220a: EP-FXT follow-up observation
  63. GRB 251220B: SVOM/GRM observation of a short burst
  64. EP251220a: COLIBRÍ confirmation of fading and photometric redshift upper limit of z < 3.4
  65. EP 251220a: GOTO optical counterpart detection
  66. GRB 251221A: COLIBRÍ detection of the optical counterpart
  67. EP 251220a: COLIBRÍ detection of the optical counterpart
  68. EP251220a: Global MASTER-Net observations report
  69. GRB 251219A: SVOM/GRM observation of a short burst
  70. Fermi-LAT Gamma-ray Observations of IceCube-251218A
  71. IceCube-251218A: Upper limits from a search for additional neutrino events in IceCube
  72. IceCube-251218A: COLIBRÍ optical upper limits
  73. GRB 251214B: VIRT Optical Upper Limit
  74. Fermi GRB 251217A: Global MASTER-Net observations report
  75. GRB 251215A: Swift/UVOT Upper LImits
  76. GRB 251215A: Fermi GBM Observation
  77. Fermi GRB 251216A: Global MASTER-Net observations report
  78. GRB 251202A/EP251202a: Koshka optical upper limit
  79. GRB 251214B: Mondy optical upper limit
  80. GRB 251215A: COLIBRÍ optical upper limit
  81. EP251214b: KAIT optical upper limit
  82. Fermi GRB 251215A: Global MASTER-Net observations report
  83. EP251214a: Optical upper limit with Kinder observations
  84. GRB 251214B: 1.6m Mephisto observations with newly installed mosaic cameras
  85. GRB 251215A: Glowbug gamma-ray detection
  86. GRB 251214B: UAFO optical upper limit
  87. GRB 251214B: VLT/X-shooter observations
  88. GRB 251213A: GRID-10B observation
  89. GRB 251214B: Swift-BAT refined analysis
  90. GRB 251202A: radio detection with the VLA
  91. EP251214b: Global MASTER-Net observations report
  92. EP251214b : Einstein Probe detection of a fast X-ray transient
  93. EP251214b : Einstein Probe detection of a fast X-ray transient
  94. GRB 251214B: AbAO optical observations
  95. GRB 251214B: LCO detection of the optical counterpart
  96. GRB 251209A: GECAM-B observation of a long burst
  97. GRB 251214D: GECAM-B observation of a long burst
  98. GRB 251214B: Fermi GBM Observation
  99. GRB 251209A: Insight-HXMT/HE detection
  100. GRB 251215A: Swift ToO observations

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