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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

38207 results found.

  1. GRB 251116B: SVOM/ECLAIRs refined analysis
  2. GRB 251117A: AstroSat CZTI detection
  3. GRB 251114B: Insight-HXMT/HE detection
  4. GRB 251114B: GECAM-B detection of a short burst
  5. GRB 251117A: Fermi GBM observation
  6. GRB 251013C: Koshka, SAO RAS, Mondy, and CrAO optical observations, possible SN detection
  7. GRB 251116D: Insight-HXMT/HE detection
  8. GRB 251115A: Swift-XRT observations
  9. GRB 251117A: Swift/BAT-GUANO localization skymap of a short burst
  10. GRB 251117A: SVOM/GRM observation of a short burst
  11. GRB 251117A: Tiled Swift observations
  12. GRB 251117A: Fermi-LAT detection
  13. LAT GRB251117.51: Global MASTER-Net observations report
  14. GRB 251116C: Swift/BAT arcminute localization of a burst
  15. GRB 251116B: SVOM/VT optical upper limit
  16. GRB 251116C: Swift-XRT observations
  17. GRB 251117A: Fermi GBM Final Localization Correction
  18. GRB 251116D: Glowbug gamma-ray detection
  19. EP251023a: Assy AZT-20 optical observations
  20. EP251023a: UAFO and AbAO optical observations
  21. GRB 251116D: AstroSat CZTI detection
  22. The EP-WXT trigger 01709247588: more evidence of flaring star from Mondy optical observations
  23. GRB 251116C: SVOM/VT optical upper limit
  24. GRB 251025B: further Mondy optical observations
  25. GRB 251111A: Mondy optical upper limit
  26. GRB 251116B: EP-FXT follow-up observation
  27. GRB 251116B: LCO optical upper limits
  28. GRB 251116C: LCO optical upper limits
  29. SVOM GRB251116C: Global MASTER-Net observations report
  30. GRB 251116C: SVOM detection of a burst
  31. GRB 251116B: SVOM detection of a burst
  32. GRB 251116A: Fermi GBM Final Real-time Localization
  33. GRB 251115A: Tiled Swift observations
  34. GRB 251115A: Fermi-LAT detection
  35. GRB 251013C: joint SVOM/ECLAIRs-GRM refined analysis
  36. Fermi GRB 251115A: Global MASTER-Net observations report
  37. GRB 251115A: Fermi GBM Final Real-time Localization
  38. GRB 251113A: Glowbug gamma-ray detection
  39. GRB 251113A: AstroSat CZTI detection
  40. GRB 251114B: Fermi GBM Final Real-time Localization
  41. GRB 251112A: Swift-BAT refined analysis
  42. Konus-Wind detection of GRB 251108C
  43. Fermi trigger No 784717756: Global MASTER-Net observations report
  44. Konus-Wind detection of GRB 251103A
  45. IPN triangulation of GRB 251108C
  46. Fermi GRB 251114A: Global MASTER-Net observations report
  47. LIGO/Virgo/KAGRA S251112cm: Candidates from the Zwicky Transient Facility
  48. GRB 251114A: Fermi GBM Final Real-time Localization
  49. Fermi GRB 251113A: Global MASTER-Net observations report
  50. GRB 251113A: BALROG localization (Fermi Trigger 784748255 / GRB 251113734)
  51. GRB 251113A: Fermi GBM Final Real-time Localization
  52. GRB 251111A: SVOM/ECLAIRs refined analysis
  53. GRB 251025B: SVOM/ECLAIRs refined analysis
  54. Fermi Gamma-ray Burst Monitor trigger 784717756/251113381 is not a GRB
  55. GRB 251112A: Swift/UVOT Upper Limits
  56. GRB 251112A: Swift-XRT refined Analysis
  57. GRB 251108C: AstroSat CZTI detection
  58. GRB 251112B: MAXI/GSC detection
  59. Fermi Gamma-ray Burst Monitor trigger 784687703/251113034 is not a GRB
  60. Fermi Gamma-ray Burst Monitor trigger 784687099/251113027 is not a GRB
  61. GRB 251108B: Glowbug gamma-ray detection
  62. Swift Trigger 1413695: a possible GRB 251112A
  63. LIGO/Virgo/KAGRA S251112cm: Upper limits from Fermi-GBM Observations
  64. Fermi trigger No 784621743: Global MASTER-Net observations report
  65. Fermi Gamma-ray Burst Monitor trigger 784653403/251112637 is not a GRB
  66. GRB 251106B: Glowbug gamma-ray detection of a likely short burst
  67. GRB 251111A: Swift-XRT afterglow detection
  68. GRB 251111A: SVOM/VT optical observations with X-band data
  69. SVOM GRB251111.42: Global MASTER-Net observations report
  70. GRB 251111A: Swift-XRT observations
  71. SVOM GRB251111.22: Global MASTER-Net observations report
  72. GRB 251111A: EP-FXT counterpart detection
  73. GRB 251013C: Chandra X-ray observations and jet break detection
  74. GRB 251111A: SVOM/VT optical observations with VHF data
  75. GRB 251111A: KAIT optical upper limit
  76. GRB 251111A: LCO optical observation
  77. GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
  78. GRB 251111A: SVOM detection of a soft burst
  79. GRB 251103B: Swift-BAT refined analysis
  80. GRB 251106A: Swift/UVOT Upper Limits
  81. GRB 251105B: Insight-HXMT/HE detection
  82. GRB 251106B: Insight-HXMT detection
  83. GRB 251105A: AstroSat CZTI detection
  84. GRB 251108A: Fermi GBM Final Localization Correction
  85. Fermi trigger No 784329591: Global MASTER-Net observations report
  86. Fermi trigger No 784279167: Global MASTER-Net observations report
  87. SVOM GRB251108.54: Global MASTER-Net observations report
  88. GRB 251102B: SVOM/GRM observation
  89. Fermi Gamma-ray Burst Monitor trigger 784279167/251108305 is not a GRB
  90. SVOM GRB251106.83: Global MASTER-Net observations report
  91. IPN triangulation of GRB 251105B (possible sGRB with EE)
  92. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
  93. GRB 251106B: SVOM/GRM observation of a short burst
  94. GRB 251106A: Swift-XRT afterglow detection
  95. GRB 251106A: Kilonova-Catcher optical upper limit
  96. Fermi GBM Sub-Threshold Detection of GRB 251106A
  97. GRB 251106A: Swift/BAT arcminute localization of a burst
  98. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) detection of a likely optical counterpart
  99. GRB 251106A: MASTER optical observations
  100. GRB 251106A: SVOM detection of a burst

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