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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"

11552 results found.

  1. Fermi GBM Sub-Threshold Detection of GRB 251105B
  2. Fermi GRB 251105A: Global MASTER-Net observations report
  3. GRB 251105A: Fermi GBM Final Real-time Localization
  4. Fermi Gamma-ray Burst Monitor trigger 783986701/251104920 is not a GRB
  5. GRB 251103B: Fermi GBM observation
  6. GRB 251028A: Insight-HXMT/HE detection
  7. GRB 251103A: WFST optical observations
  8. GRB 251103A: OHP/T193 optical observations
  9. GRB 251103A: Xinglong 2.16m optical detection
  10. GRB 251103A: Insight-HXMT detection
  11. GRB 251103A: KAIT optical observations
  12. GRB 251103B: Nanshan/HMT optical upper limit
  13. GRB 251013C: 7DT detection and Medium-band SED of Afterglow
  14. GRB 251103A: Swift/BAT-GUANO arcminute localization of a burst
  15. GRB 251103B: MITSuME Akeno optical upper limits
  16. Fermi GRB 251103A: Global MASTER-Net observations report
  17. GRB 251103A: J-band detection with WINTER
  18. GRB 251103B: GROWTH-India Telescope optical upper limits
  19. GRB 251103A: Kilonova-Catcher optical afterglow detection
  20. GRB 251103B: Fermi GBM Final Real-time Localization
  21. GRB 251103A: Fermi GBM Observation
  22. GRB 251103A: SVOM/GRM observation
  23. GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
  24. GRB 251103A: GOTO optical afterglow detection
  25. GRB 251102A: AstroSat CZTI detection
  26. GRB 251103A: NOT spectroscopic redshift z = 0.76
  27. GRB 251103A: Fermi GBM Final Localization
  28. GRB 251102B: Fermi GBM Final Real-time Localization
  29. Fermi GRB 251102A: Global MASTER-Net observations report
  30. GRB 251102A: Fermi GBM Final Real-time Localization
  31. GRB 251031A: Fermi GBM Observation
  32. GRB 251031A: Swift/BAT-GUANO localization skymap of a burst
  33. Konus-Wind detection of GRB 251028A
  34. GRB 251031A: BALROG localization (Fermi Trigger 783588065 / GRB 251031306)
  35. GRB 251031A: Fermi GBM Final Real-time Localization
  36. GRB 251025C: SVOM/GRM observation
  37. GRB 251028A: GECAM-B detection
  38. GRB 251028A: SVOM/GRM observation
  39. GRB 251028A: Fermi GBM Observation
  40. GRB 251022A: Swift-XRT confirmation of fading
  41. GRB 251026B: LBT near-infrared observations
  42. GRB 250926B: VZLUSAT-2 detection
  43. GRB 250926A: VZLUSAT-2 detection
  44. GRB 251026B: Fermi GBM Observation
  45. GRB 251028B: Fermi/GBM observation
  46. GRB 251028B: Swift/BAT-GUANO localization skymap of a burst
  47. GRB 251028B: Glowbug gamma-ray detection
  48. GRB 251028A: Glowbug gamma-ray detection
  49. GRB 251028B: CALET Gamma-Ray Burst Monitor detection
  50. Fermi GRB 251028B: Global MASTER-Net observations report
  51. GRB 251028B: Fermi GBM Final Localization Correction
  52. GRB251026B: PRIME H-band upper limit
  53. GRB 251028A: BALROG localization (Fermi Trigger 783314796 / GRB 251028143)
  54. GRB 251028A: Fermi GBM Final Real-time Localization
  55. GRB 251013C : 3.4-m telescope of Iranian National Observatory (INO340) optical observations
  56. GRB 251026B: Swift-XRT observations of GOTO25jgl/AT2025absf
  57. GRB 251025C: Glowbug gamma-ray detection
  58. Fermi-LAT Gamma-ray Observations of IceCube-251025A
  59. Konus-Wind detection of GRB 251022A
  60. GRB 251022A: SVOM/GRM observation
  61. GRB 251026B: Swift ToO observations
  62. Konus-Wind detection of GRB 251016A (short/hard)
  63. GRB 251026B: Tentative GOTO optical counterpart candidate
  64. GRB 251025C: CALET Gamma-Ray Burst Monitor detection
  65. Fermi GRB 251026B: Global MASTER-Net observations report
  66. Fermi GRB 251025C: Global MASTER-Net observations report
  67. GRB 251026B: Fermi GBM Final Localization
  68. GRB 251023A: SVOM/GRM observation
  69. GRB 251025C: Fermi GBM Final Real-time Localization
  70. Konus-Wind detection of GRB 251016B
  71. IceCube-251025A - IceCube observation of a high-energy neutrino candidate track-like event
  72. GRB 251003A: VLA Detection
  73. GRB 251022A: KAIT optical observations
  74. GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
  75. GRB 251022A: Swift-XRT detection of GOTO25iym
  76. GRB 251022A: GROWTH-India Telescope optical observations
  77. GRB 251022A: Fermi GBM Observation
  78. GRB 251022A: Swift/BAT-GUANO localization skymap of a burst
  79. GRB 251023A: Glowbug gamma-ray detection
  80. IPN triangulation of GRB 251016B
  81. GRB 251013C: further SAO RAS optical observations
  82. GRB 251022A: COLIBRÍ optical observations
  83. GRB 251013C: ISON-Castelgrande observatory optical observations
  84. GRB 251022A: MASTER OT detection
  85. GRB 251022A: DDOTI Optical Detection
  86. Fermi GRB 251023A: Global MASTER-Net observations report
  87. GRB 251022A: GOTO optical counterpart detection
  88. GRB 251023A: Fermi GBM Final Localization Correction
  89. GRB 251022A: Fermi-LAT detection
  90. GRB 251016B: Fermi GBM Detection
  91. GRB 251022A: Tiled Swift observations
  92. GRB 251022A: Fermi GBM Final Real-time Localization
  93. GRB 251021A/EP251021b: Fermi-GBM Sub-Threshold Detection
  94. GRB 251016A: SVOM/ECLAIRs refined analysis
  95. Fermi-LAT gamma-ray observations of IceCube-251018A
  96. GRB 251016A: Fermi GBM Observation
  97. GRB 251018A: Fermi GBM Observation
  98. GRB 251018A: BOOTES-5 and BOOTES-7 early optical detections
  99. Fermi trigger No 782500909: Global MASTER-Net observations report
  100. GRB 251016A: HXMT/HE detection

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