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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"

32771 results found.

  1. GRB 251222A: ZTSH BVRI optical observations
  2. GRB 251222A: SVOM/COLIBRÍ (FM-GFT) optical observations
  3. GRB 251222A: Continued 1.3m DFOT optical observation
  4. EP251220a: 3.6m DOT optical afterglow detection
  5. GRB 251222A: Fermi GBM Observation
  6. EP251220a: CrAO ZTSh optical observations
  7. EP251221a: PRIME upper limit
  8. EP251222a: Global MASTER-Net observations report
  9. GRB 251222A / EP251222b: GECAM-B observation
  10. EP251221a: Liverpool Telescope upper limits
  11. EP251222a: refined analysis of the EP-WXT and EP-FXT observations
  12. EP251222b/GRB 251222A: refined analysis of the EP-WXT and EP-FXT observations
  13. Konus-Wind detection of GRB 251222A / EP251222b
  14. GRB 251222A / EP251222b: LCO detection of the optical counterpart
  15. EP251222a: NTT/ULTRACAM optical observations
  16. EP251222a: GOTO optical upper limit
  17. GRB 251222A / EP251222b: GOTO optical counterpart detection
  18. GRB 251222A / EP251222b: LCO optical observations
  19. GRB 251222A: 1.3m DFOT optical detection
  20. GRB251221A: 7DT optical upper limits
  21. EP251222a: GSP Optical Counterpart Detection
  22. GRB 251222A / EP251222b: VLT/X-shooter spectroscopic redshift z = 3.171
  23. GRB 251222A / EP251222b: SVOM/VT optical rebrightening
  24. EP251222b/GRB 251222A: SVOM/GRM observation
  25. EP251222b/GRB 251222A: Einstein Probe detection of an X-ray transient
  26. EP251221a: Global MASTER-Net observations report
  27. GRB 251222A: PRIME near-infrared detection
  28. EP251221a: NOT optical upper limit
  29. GRB 251222A: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  30. GRB 251222A: NOT optical observations
  31. IceCube-251218A: No Candidate Transients from the Zwicky Transient Facility
  32. IPN triangulation of GRB 251220B (short)
  33. GRB 251222A: Swift ToO observations
  34. GRB 251222A: SVOM/VT optical candidate
  35. GRB 251222A: SVOM detection of a long burst
  36. EP251220a: PRIME upper limit
  37. EP251220a: VLT/FORS2 spectroscopic redshift z = 2.375
  38. GRB 251221A: PRIME near-infrared observation
  39. EP251220a: NOT optical observations
  40. EP251220a: FTW optical and NIR observations
  41. GRB 251221A: UAFO and Mondy optical upper limit
  42. GRB 251221A: Swift/UVOT Upper Limits
  43. GRB 251221A: Fermi GBM Observation
  44. EP251220a: EP-FXT follow-up observation
  45. GRB 251220B: SVOM/GRM observation of a short burst
  46. EP251220a: COLIBRÍ confirmation of fading and photometric redshift upper limit of z < 3.4
  47. EP 251220a: GOTO optical counterpart detection
  48. GRB 251221A: COLIBRÍ detection of the optical counterpart
  49. EP 251220a: COLIBRÍ detection of the optical counterpart
  50. EP251220a: Global MASTER-Net observations report
  51. GRB 251219A: SVOM/GRM observation of a short burst
  52. Fermi-LAT Gamma-ray Observations of IceCube-251218A
  53. IceCube-251218A: Upper limits from a search for additional neutrino events in IceCube
  54. IceCube-251218A: COLIBRÍ optical upper limits
  55. GRB 251214B: VIRT Optical Upper Limit
  56. Fermi GRB 251217A: Global MASTER-Net observations report
  57. GRB 251215A: Swift/UVOT Upper LImits
  58. GRB 251215A: Fermi GBM Observation
  59. Fermi GRB 251216A: Global MASTER-Net observations report
  60. GRB 251202A/EP251202a: Koshka optical upper limit
  61. GRB 251214B: Mondy optical upper limit
  62. GRB 251215A: COLIBRÍ optical upper limit
  63. EP251214b: KAIT optical upper limit
  64. Fermi GRB 251215A: Global MASTER-Net observations report
  65. EP251214a: Optical upper limit with Kinder observations
  66. GRB 251214B: 1.6m Mephisto observations with newly installed mosaic cameras
  67. GRB 251215A: Glowbug gamma-ray detection
  68. GRB 251214B: UAFO optical upper limit
  69. GRB 251214B: VLT/X-shooter observations
  70. GRB 251213A: GRID-10B observation
  71. GRB 251214B: Swift-BAT refined analysis
  72. GRB 251202A: radio detection with the VLA
  73. EP251214b: Global MASTER-Net observations report
  74. EP251214b : Einstein Probe detection of a fast X-ray transient
  75. EP251214b : Einstein Probe detection of a fast X-ray transient
  76. GRB 251214B: AbAO optical observations
  77. GRB 251214B: LCO detection of the optical counterpart
  78. GRB 251209A: GECAM-B observation of a long burst
  79. GRB 251214D: GECAM-B observation of a long burst
  80. GRB 251214B: Fermi GBM Observation
  81. GRB 251209A: Insight-HXMT/HE detection
  82. GRB 251215A: Swift ToO observations
  83. EP251214b (EP trigger 01709250023): LCO optical limits
  84. GRID detection of GRB 251213A
  85. GRB 251203B: AbAO optical observations
  86. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  87. GRB 251214B: GECAM-B observation of a long burst
  88. GRB 251213A: SVOM/GRM observation
  89. EP251214a: KAIT optical upper limit
  90. GRB 251213A: AstroSat CZTI detection
  91. GRB 251214A: AstroSat CZTI detection
  92. GRB 251214B: Swift/UVOT Detection
  93. GRB 251214B: COLIBRÍ observations of the afterglow
  94. EP251214a: EP-FXT non-detection and upper limit
  95. GRB 251214A: GECAM-B observation of a likely long burst
  96. GRB 251214B: 1.3m DFOT optical detection
  97. EP251214a: Global MASTER-Net observations report
  98. GRB 251214B: Xinglong-2.16m optical observation
  99. GRB 251214B : MASTER optical afterglow detection
  100. GRB 251214B: SVOM/C-GFT optical observations

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