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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"

15361 results found.

  1. GRB 251105A: AstroSat CZTI detection
  2. LIGO/Virgo/KAGRA S251108fi: One counterpart neutrino candidate from IceCube neutrino searches
  3. IceCube-Cascade 251107A: Upper limits from a search for additional neutrino events in IceCube
  4. GRB 251102B: SVOM/GRM observation
  5. The EP-WXT trigger 01709248051 is likely a flaring star
  6. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
  7. GRB 251106B: SVOM/GRM observation of a short burst
  8. GRB 251106A: Kilonova-Catcher optical upper limit
  9. GRB 251106A: SVOM detection of a burst
  10. GRB 251103B: AstroSat CZTI detection
  11. GRB 251025C: TERI Gamma-ray detection
  12. GRB 251016B: TERI Gamma-ray detection
  13. GRB 251016A: TERI Gamma-ray detection of a short burst
  14. GRB 250920C: TERI Gamma-ray detection
  15. EP251102a: Xinglong 2.16-m clear-band observations of the optical counterpart
  16. GRB 251105A: Fermi GBM Observation
  17. LIGO/Virgo/KAGRA S251031dw: Candidates from the Zwicky Transient Facility
  18. GRB 251105A: Swift/BAT-GUANO localization skymap of a burst
  19. GRB 251105B: AstroSat CZTI detection of a short burst with extended emission
  20. GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
  21. GRB 251105B: SVOM/GRM observation of a possible short burst with extended emission
  22. GRB 251103B: Fermi GBM observation
  23. GRB 251104A: SVOM detection of a burst
  24. GRB 251028A: Insight-HXMT/HE detection
  25. EP251102a: update of EP-FXT follow-up observation
  26. GRB 251103A: Insight-HXMT detection
  27. GRB 251103B: Nanshan/HMT optical upper limit
  28. GRB 251013C: 7DT detection and Medium-band SED of Afterglow
  29. GRB 251103A: Kilonova-Catcher optical afterglow detection
  30. GRB 251103A: Fermi GBM Observation
  31. GRB 251103A: SVOM/GRM observation
  32. GRB 251103A: Swift-XRT afterglow detection
  33. GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
  34. EP251102a: Einstein Probe detection of a fast X-ray transient
  35. GRB 251103A: LCO optical observation
  36. GRB 251102A: AstroSat CZTI detection
  37. GRB 251026A: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical counterpart
  38. GRB 251103A: BOOTES-2/TELMA optical afterglow
  39. GRB 251103A: LCO optical afterglow detection
  40. GRB 251103A: SVOM detection of a bright burst
  41. GRB 251031A: Fermi GBM Observation
  42. GRB 251031A: Swift/BAT-GUANO localization skymap of a burst
  43. Konus-Wind detection of GRB 251028A
  44. GRB 251025C: SVOM/GRM observation
  45. GRB 251028A: GECAM-B detection
  46. GRB 251028A: SVOM/GRM observation
  47. IceCube-251025A: Two Transient Candidates from the Zwicky Transient Facility
  48. GRB 251026B: SOAR Classification of GOTO25jgl/SN2025absf as a Type Ia supernova
  49. GRB 251022A: Swift-XRT confirmation of fading
  50. GRB 251026B: LBT near-infrared observations
  51. GRB 250926B: VZLUSAT-2 detection
  52. GRB 250926A: VZLUSAT-2 detection
  53. GRB 250925A: VZLUSAT-2 detection
  54. GRB 251028B: Fermi/GBM observation
  55. GRB 251028B: Swift/BAT-GUANO localization skymap of a burst
  56. GRB 251028A: Glowbug gamma-ray detection
  57. IceCube-251025A: Upper limits from a search for additional neutrino events in IceCube
  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. GRB 251026A/EP251026a: Einstein Probe detection of a fast X-ray transient
  63. GRB 251027A: LCO optical upper limit
  64. GRB 251023B / EP251023b: Mondy optical upper limit
  65. GRB 251025B: Kilonova-Catcher optical afterglow detection
  66. Konus-Wind detection of GRB 251016A (short/hard)
  67. GRB 251027A: SVOM detection of a faint burst
  68. GRB 251025C: AstroSat CZTI detection
  69. IceCube-251025A: DDOTI Optical Upper Limit
  70. GRB 251026A: SVOM detection of a long burst
  71. GRB 251023A: SVOM/GRM observation
  72. Konus-Wind detection of GRB 251016B
  73. GRB 251025A (sb25102501): stellar flare confirmed
  74. GRB 251025B: SVOM/VT optical observations with VHF data
  75. GRB 251025B: SVOM detection of a burst
  76. IceCube-251025A - IceCube observation of a high-energy neutrino candidate track-like event
  77. GRB 251025A (sb25102501): Likely a stellar flare by SVOM/VT
  78. GRB 251025A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  79. GRB 251025A: SVOM detection of a faint burst
  80. GRB 251023C: Glowbug gamma-ray detection
  81. GRB 251023B / EP251023b: COLIBRÍ Confirmation of the Fading Nature of the Optical Candidate
  82. GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
  83. GRB 251023C: AstroSat CZTI detection
  84. EP251023b/GRB 251023B: JinShan optical observation
  85. GRB 251022A: Swift-XRT detection of GOTO25iym
  86. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  87. EP251023a: GROWTH-India Telescope optical observations
  88. GRB 251022A: Fermi GBM Observation
  89. GRB 251022A: Swift/BAT-GUANO localization skymap of a burst
  90. GRB 251023B: Glowbug gamma-ray detection
  91. EP251023a: COLIBRÍ optical observations
  92. GRB 251022A: COLIBRÍ optical observations
  93. GRB 251022A: DDOTI Optical Detection
  94. EP251023a: GSP Optical Counterpart Detection
  95. EP251023a: Einstein Probe detection of an X-ray transient
  96. GRB 251022A: Fermi-LAT detection
  97. GRB 251016B: Fermi GBM Detection
  98. GRB 251022A: Tiled Swift observations
  99. GRB 251016A: SVOM/ECLAIRs refined analysis
  100. Fermi-LAT gamma-ray observations of IceCube-251018A

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