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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"

15275 results found.

  1. GRB 251108C: AstroSat CZTI detection
  2. LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
  3. LIGO/Virgo/KAGRA S251112cm: Upper limits from Fermi-GBM Observations
  4. GRB 251111A: Swift-XRT observations
  5. GRB 251111A: EP-FXT counterpart detection
  6. GRB 251013C: Chandra X-ray observations and jet break detection
  7. GRB 251111A: SVOM/VT optical observations with VHF data
  8. GRB 251111A: KAIT optical upper limit
  9. GRB 251111A: LCO optical observation
  10. GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
  11. GRB 251111A: SVOM detection of a soft burst
  12. GRB 251105B: Insight-HXMT/HE detection
  13. GRB 251106B: Insight-HXMT detection
  14. LIGO/Virgo/KAGRA S251108fi: DDOTI Optical Candidate
  15. GRB 251105A: AstroSat CZTI detection
  16. LIGO/Virgo/KAGRA S251108fi: One counterpart neutrino candidate from IceCube neutrino searches
  17. IceCube-Cascade 251107A: Upper limits from a search for additional neutrino events in IceCube
  18. GRB 251102B: SVOM/GRM observation
  19. The EP-WXT trigger 01709248051 is likely a flaring star
  20. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
  21. GRB 251106B: SVOM/GRM observation of a short burst
  22. GRB 251106A: Kilonova-Catcher optical upper limit
  23. GRB 251106A: SVOM detection of a burst
  24. GRB 251103B: AstroSat CZTI detection
  25. GRB 251025C: TERI Gamma-ray detection
  26. GRB 251016B: TERI Gamma-ray detection
  27. GRB 251016A: TERI Gamma-ray detection of a short burst
  28. GRB 250920C: TERI Gamma-ray detection
  29. EP251102a: Xinglong 2.16-m clear-band observations of the optical counterpart
  30. GRB 251105A: Fermi GBM Observation
  31. LIGO/Virgo/KAGRA S251031dw: Candidates from the Zwicky Transient Facility
  32. GRB 251105A: Swift/BAT-GUANO localization skymap of a burst
  33. GRB 251105B: AstroSat CZTI detection of a short burst with extended emission
  34. GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
  35. GRB 251105B: SVOM/GRM observation of a possible short burst with extended emission
  36. GRB 251103B: Fermi GBM observation
  37. GRB 251104A: SVOM detection of a burst
  38. GRB 251028A: Insight-HXMT/HE detection
  39. EP251102a: update of EP-FXT follow-up observation
  40. GRB 251103A: Insight-HXMT detection
  41. GRB 251103B: Nanshan/HMT optical upper limit
  42. GRB 251013C: 7DT detection and Medium-band SED of Afterglow
  43. GRB 251103A: Kilonova-Catcher optical afterglow detection
  44. GRB 251103A: Fermi GBM Observation
  45. GRB 251103A: SVOM/GRM observation
  46. GRB 251103A: Swift-XRT afterglow detection
  47. GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
  48. EP251102a: Einstein Probe detection of a fast X-ray transient
  49. GRB 251103A: LCO optical observation
  50. GRB 251102A: AstroSat CZTI detection
  51. GRB 251026A: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical counterpart
  52. GRB 251103A: BOOTES-2/TELMA optical afterglow
  53. GRB 251103A: LCO optical afterglow detection
  54. GRB 251103A: SVOM detection of a bright burst
  55. GRB 251031A: Fermi GBM Observation
  56. GRB 251031A: Swift/BAT-GUANO localization skymap of a burst
  57. Konus-Wind detection of GRB 251028A
  58. GRB 251025C: SVOM/GRM observation
  59. GRB 251028A: GECAM-B detection
  60. GRB 251028A: SVOM/GRM observation
  61. IceCube-251025A: Two Transient Candidates from the Zwicky Transient Facility
  62. GRB 251026B: SOAR Classification of GOTO25jgl/SN2025absf as a Type Ia supernova
  63. GRB 251022A: Swift-XRT confirmation of fading
  64. GRB 251026B: LBT near-infrared observations
  65. GRB 250926B: VZLUSAT-2 detection
  66. GRB 250926A: VZLUSAT-2 detection
  67. GRB 250925A: VZLUSAT-2 detection
  68. GRB 251028B: Fermi/GBM observation
  69. GRB 251028B: Swift/BAT-GUANO localization skymap of a burst
  70. GRB 251028A: Glowbug gamma-ray detection
  71. IceCube-251025A: Upper limits from a search for additional neutrino events in IceCube
  72. Fermi-LAT Gamma-ray Observations of IceCube-251025A
  73. Konus-Wind detection of GRB 251022A
  74. GRB 251022A: SVOM/GRM observation
  75. GRB 251026B: Swift ToO observations
  76. GRB 251026A/EP251026a: Einstein Probe detection of a fast X-ray transient
  77. GRB 251027A: LCO optical upper limit
  78. GRB 251023B / EP251023b: Mondy optical upper limit
  79. GRB 251025B: Kilonova-Catcher optical afterglow detection
  80. Konus-Wind detection of GRB 251016A (short/hard)
  81. GRB 251027A: SVOM detection of a faint burst
  82. GRB 251025C: AstroSat CZTI detection
  83. IceCube-251025A: DDOTI Optical Upper Limit
  84. GRB 251026A: SVOM detection of a long burst
  85. GRB 251023A: SVOM/GRM observation
  86. Konus-Wind detection of GRB 251016B
  87. GRB 251025A (sb25102501): stellar flare confirmed
  88. GRB 251025B: SVOM/VT optical observations with VHF data
  89. GRB 251025B: SVOM detection of a burst
  90. IceCube-251025A - IceCube observation of a high-energy neutrino candidate track-like event
  91. GRB 251025A (sb25102501): Likely a stellar flare by SVOM/VT
  92. GRB 251025A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  93. GRB 251025A: SVOM detection of a faint burst
  94. GRB 251023C: Glowbug gamma-ray detection
  95. GRB 251023B / EP251023b: COLIBRÍ Confirmation of the Fading Nature of the Optical Candidate
  96. GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
  97. GRB 251023C: AstroSat CZTI detection
  98. EP251023b/GRB 251023B: JinShan optical observation
  99. GRB 251022A: Swift-XRT detection of GOTO25iym
  100. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient

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