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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"

32617 results found.

  1. EP250225a: SVOM/VT optical brightening
  2. SVOM/sb25041603 is not a GRB
  3. EP250416a: GSP optical upper limit
  4. EP250416a: Global MASTER-Net observations report
  5. SVOM/sb25041603: SVOM/COLIBRÍ (FM-GFT) Upper Limit on the Optical Counterpart
  6. GRB 250413A: AstroSat CZTI detection
  7. EP250304a: ATCA radio observations
  8. EP250404a: Nanshan 0.43m Telescope optical observatios
  9. GRB 250411A: DDOTI Optical Observations
  10. Fermi GRB 250411A: Global MASTER-Net observations report
  11. GRB 250407A: Continued KAIT/Nickel optical observations
  12. GRB 250314A: e-MERLIN observations
  13. GRB 250407A: Mondy and AbAO Optical Observations
  14. EP250227a: Further NOT optical observations
  15. GRB 250320B: cubesat Avion detection
  16. IceCube-250406A: Swift-XRT observations
  17. IPN triangulation of GRB 250321D (consistent with the fast X-ray transient EP250321a)
  18. IPN triangulation of GRB 250407A
  19. EP250407a: Global MASTER-Net observations report
  20. GRB 250407A: LCO detection of a fading optical counterpart
  21. Fermi-LAT gamma-ray observations of IceCube-250406A
  22. EP250407a: Swift-XRT observations
  23. IceCube-250406A: Upper limits from a search for additional neutrino events in IceCube
  24. Konus-Wind detection of GRB 250407A
  25. GRB 250407A: SVOM/GRM observation of a bright long burst
  26. GRB 250407A: EP-WXT afterglow detection
  27. EP250407a: EP-WXT detection of a fast X-ray transient
  28. GRB 250407A: COLIBRÍ/DDRAGO Detection of the Optical Counterpart
  29. GRB 250407A: KAIT Optical Afterglow Candidate
  30. IceCube-250406A: No candidates from the Zwicky Transient Facility
  31. GRB 250407A: Fermi GBM Detection
  32. GRB 250407A: Swift-XRT afterglow detection
  33. Fermi GRB 250407A: Global MASTER-Net observations report
  34. GRB 250407A: Swift ToO observations
  35. GRB 250407A: SRG/ART-XC afterglow detection
  36. IceCube 250406A: DDOTI Optical Observations of the Refined Position
  37. Konus-Wind detection of GRB 250406B (short/hard)
  38. IPN triangulation of GRB 250406B (short/hard)
  39. IceCube 250406.951: COLIBRÍ/DDRAGO Optical Upper Limit
  40. GRB 250406A: AstroSat CZTI detection
  41. EP250404a: Multi-band Optical Observations from UCAS-70 and XL-C14
  42. Fermi GRB 250406A: Global MASTER-Net observations report
  43. GRB 250404A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations.
  44. EP250404a / GRB 250404A: Montarrenti Observatory optical observations
  45. GRB 250404A / EP250404a: RC500 INASAN-Kislovodsk optical upper limit
  46. GRB 250404A / EP250404a: SVOM/GWAC-F60 and F50 observations
  47. EP250404a / GRB 250404A: J band observations by SYSU 80cm telescope
  48. Konus-Wind detection of GRB 250404A / EP250404a
  49. GRB 250404A / EP250404a: Mondy optical observations
  50. EP250404a: refined analysis of the EP-WXT and EP-FXT observations
  51. GRB 250404A / EP250404a: GMG spectroscopic redshift at z ~ 2.627
  52. GRB 250404A / EP250404a: Leavitt Observatory optical counterpart detection
  53. GRB 250402A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations.
  54. EP250402a: Optical upper limit with PD 1.3m observations
  55. GRB 250404A / EP250404a: NOT optical observations
  56. GRB 250403A: AstroSat CZTI detection
  57. EP250404a: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  58. EP250404a: REM optical/NIR observations
  59. EP250404a: Seimei/TriCCS optical counterpart detection
  60. EP250404A: COLIBRÍ/DDRAGO Optical Observations
  61. EP250404A / GRB250404A: Ondrejov D50 optical afterglow detection
  62. EP250404a: LCO optical counterpart detection
  63. Fermi GRB 250404A: Global MASTER-Net observations report
  64. GRB 250403A: Montarrenti Observatory optical detection
  65. EP250404a: Global MASTER-Net observations report
  66. GRB 250403A: KAIT optical observations
  67. EP250404a: AKO Optical Afterglow Detection
  68. EP250404a: LAST detection of optical counterpart
  69. GRB 250402A: Swift/BAT-GUANO localization skymap of a burst
  70. EP250404a: Xinglong-2.16m spectroscopic redshift
  71. GRB 250403A: Fermi GBM observations
  72. GRB 250327B: VIRT Optical Upper Limit
  73. EP250404a: Mephisto multi-band optical detection
  74. GRB 250331C Swift-BAT refined analysis
  75. GRB 250331B Swift-BAT refined analysis
  76. GRB 250330A Swift-BAT refined analysis
  77. EP250321A: J band upper limit by SYSU 80cm telescope
  78. EP250404a: BOOTES-4/JGT optical afterglow detection
  79. EP250404a: Nanshan/HMT optical counterpart detection
  80. EP250404a: Einstein Probe detection of an X-ray transient
  81. GRB 250402A: Mondy optical observations
  82. GRB 250403A: Swift/UVOT Detection
  83. GRB 250402A: Swift/UVOT Upper Limits
  84. EP250402a: Optical upper limit with Kinder observations
  85. GRB 250403A: SVOM/VT optical observation
  86. GRB 250403A: REM NIR afterglow detection
  87. GRB 250403A: LCO optical counterpart detection
  88. IceCube-250330A: MASTER detection of PKS 2032+107 blazar flare with Zhirkov effect
  89. GRB 250403A: JinShan optical observations
  90. GRB 250402A: EP-FXT afterglow detection
  91. GRB 250403A: Optical counterpart detection by LCO.
  92. EP250402a: EP-FXT follow-up observations
  93. GRB 250403A: Swift-XRT observations
  94. GRB 250322A: 10 GHz VLA radio upper limits
  95. Fermi GRB 250403A: Global MASTER-Net observations report
  96. GRB 250403A: GOTO optical counterpart follow-up observations
  97. GRB 250402A: NUTTelA-TAO Early Optical Limits
  98. GRB 250403A: GMG Optical Observation
  99. GRB 250403A: 1.6m Mephisto multi-band optical detection
  100. GRB 250402A: Fermi GBM Observation

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