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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"

36316 results found.

  1. GRB 251117A: Fermi GBM observation
  2. GRB 251013C: Koshka, SAO RAS, Mondy, and CrAO optical observations, possible SN detection
  3. GRB 251116D: Insight-HXMT/HE detection
  4. GRB 251115A: Swift-XRT observations
  5. GRB 251117A: Swift/BAT-GUANO localization skymap of a short burst
  6. GRB 251117A: SVOM/GRM observation of a short burst
  7. GRB 251117A: Tiled Swift observations
  8. GRB 251117A: Fermi-LAT detection
  9. GRB 251116C: Swift/BAT arcminute localization of a burst
  10. GRB 251116B: SVOM/VT optical upper limit
  11. LIGO/Virgo/KAGRA S251112cm: WFST follow-up observations and preliminary results
  12. GRB 251116C: Swift-XRT observations
  13. GRB 251117A: Fermi GBM Final Localization Correction
  14. GRB 251116D: Glowbug gamma-ray detection
  15. EP251023a: Assy AZT-20 optical observations
  16. EP251023a: UAFO and AbAO optical observations
  17. GRB 251116D: AstroSat CZTI detection
  18. The EP-WXT trigger 01709247588: more evidence of flaring star from Mondy optical observations
  19. GRB 251116C: SVOM/VT optical upper limit
  20. GRB 251025B: further Mondy optical observations
  21. GRB 251111A: Mondy optical upper limit
  22. GRB 251116B: EP-FXT follow-up observation
  23. GRB 251116B: LCO optical upper limits
  24. GRB 251116C: LCO optical upper limits
  25. GRB 251116C: SVOM detection of a burst
  26. GRB 251116B: SVOM detection of a burst
  27. GRB 251116A: Fermi GBM Final Real-time Localization
  28. GRB 251115A: Tiled Swift observations
  29. GRB 251115A: Fermi-LAT detection
  30. GRB 251013C: joint SVOM/ECLAIRs-GRM refined analysis
  31. Fermi GRB 251115A: Global MASTER-Net observations report
  32. GRB 251115A: Fermi GBM Final Real-time Localization
  33. GRB 251113A: Glowbug gamma-ray detection
  34. GRB 251113A: AstroSat CZTI detection
  35. GRB 251114B: Fermi GBM Final Real-time Localization
  36. GRB 251112A: Swift-BAT refined analysis
  37. Konus-Wind detection of GRB 251108C
  38. Konus-Wind detection of GRB 251103A
  39. IPN triangulation of GRB 251108C
  40. Fermi GRB 251114A: Global MASTER-Net observations report
  41. GRB 251114A: Fermi GBM Final Real-time Localization
  42. Fermi GRB 251113A: Global MASTER-Net observations report
  43. GRB 251113A: BALROG localization (Fermi Trigger 784748255 / GRB 251113734)
  44. GRB 251113A: Fermi GBM Final Real-time Localization
  45. GRB 251111A: SVOM/ECLAIRs refined analysis
  46. GRB 251025B: SVOM/ECLAIRs refined analysis
  47. Fermi Gamma-ray Burst Monitor trigger 784717756/251113381 is not a GRB
  48. GRB 251112A: Swift/UVOT Upper Limits
  49. GRB 251112A: Swift-XRT refined Analysis
  50. GRB 251108C: AstroSat CZTI detection
  51. GRB 251112B: MAXI/GSC detection
  52. Fermi Gamma-ray Burst Monitor trigger 784687703/251113034 is not a GRB
  53. Fermi Gamma-ray Burst Monitor trigger 784687099/251113027 is not a GRB
  54. GRB 251108B: Glowbug gamma-ray detection
  55. Swift Trigger 1413695: a possible GRB 251112A
  56. LIGO/Virgo/KAGRA S251112cm: Upper limits from Fermi-GBM Observations
  57. Fermi Gamma-ray Burst Monitor trigger 784653403/251112637 is not a GRB
  58. GRB 251106B: Glowbug gamma-ray detection of a likely short burst
  59. GRB 251111A: Swift-XRT afterglow detection
  60. GRB 251111A: SVOM/VT optical observations with X-band data
  61. GRB 251111A: Swift-XRT observations
  62. GRB 251111A: EP-FXT counterpart detection
  63. GRB 251013C: Chandra X-ray observations and jet break detection
  64. GRB 251111A: SVOM/VT optical observations with VHF data
  65. GRB 251111A: KAIT optical upper limit
  66. GRB 251111A: LCO optical observation
  67. GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
  68. GRB 251111A: SVOM detection of a soft burst
  69. GRB 251103B: Swift-BAT refined analysis
  70. GRB 251106A: Swift/UVOT Upper Limits
  71. GRB 251105B: Insight-HXMT/HE detection
  72. GRB 251106B: Insight-HXMT detection
  73. GRB 251105A: AstroSat CZTI detection
  74. GRB 251108A: Fermi GBM Final Localization Correction
  75. GRB 251102B: SVOM/GRM observation
  76. Fermi Gamma-ray Burst Monitor trigger 784279167/251108305 is not a GRB
  77. IPN triangulation of GRB 251105B (possible sGRB with EE)
  78. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
  79. GRB 251106B: SVOM/GRM observation of a short burst
  80. GRB 251106A: Swift-XRT afterglow detection
  81. GRB 251106A: Kilonova-Catcher optical upper limit
  82. Fermi GBM Sub-Threshold Detection of GRB 251106A
  83. GRB 251106A: Swift/BAT arcminute localization of a burst
  84. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) detection of a likely optical counterpart
  85. GRB 251106A: MASTER optical observations
  86. GRB 251106A: SVOM detection of a burst
  87. GRB 251103B: AstroSat CZTI detection
  88. GRB 251025C: TERI Gamma-ray detection
  89. GRB 251016B: TERI Gamma-ray detection
  90. GRB 251016A: TERI Gamma-ray detection of a short burst
  91. GRB 250920C: TERI Gamma-ray detection
  92. Fermi Gamma-ray Burst Monitor trigger 784109140/251106337 is not a GRB
  93. GRB 251105A: Fermi GBM Observation
  94. GRB 251105C: Fermi GBM Final Localization Correction
  95. GRB 251105A: Swift/BAT-GUANO localization skymap of a burst
  96. GRB 251104A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  97. GRB 251105B: AstroSat CZTI detection of a short burst with extended emission
  98. GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
  99. Fermi GBM Sub-Threshold Detection of GRB 251105B
  100. GRB 251103B: Swift/UVOT Upper Limits

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