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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"

11612 results found.

  1. GRB 251118A: BALROG localization (Fermi Trigger 785190695 / GRB 251118855)
  2. GRB 251117A: FTW Observations of Swift candidate X-ray sources
  3. GRB 251118A: Fermi GBM Final Real-time Localization
  4. GRB 251117A: AstroSat CZTI detection
  5. GRB 251114B: Insight-HXMT/HE detection
  6. GRB 251114B: GECAM-B detection of a short burst
  7. GRB 251117A: Fermi GBM observation
  8. GRB 251013C: Koshka, SAO RAS, Mondy, and CrAO optical observations, possible SN detection
  9. GRB 251115A: Swift-XRT observations
  10. GRB 251117A: Swift/BAT-GUANO localization skymap of a short burst
  11. GRB 251117A: SVOM/GRM observation of a short burst
  12. GRB 251117A: Tiled Swift observations
  13. GRB 251117A: Fermi-LAT detection
  14. GRB 251117A: Fermi GBM Final Localization Correction
  15. GRB 251116A: Fermi GBM Final Real-time Localization
  16. GRB 251115A: Tiled Swift observations
  17. GRB 251115A: Fermi-LAT detection
  18. GRB 251013C: joint SVOM/ECLAIRs-GRM refined analysis
  19. Fermi GRB 251115A: Global MASTER-Net observations report
  20. GRB 251115A: Fermi GBM Final Real-time Localization
  21. GRB 251113A: Glowbug gamma-ray detection
  22. GRB 251113A: AstroSat CZTI detection
  23. GRB 251114B: Fermi GBM Final Real-time Localization
  24. Fermi trigger No 784717756: Global MASTER-Net observations report
  25. Konus-Wind detection of GRB 251103A
  26. Fermi GRB 251114A: Global MASTER-Net observations report
  27. GRB 251114A: Fermi GBM Final Real-time Localization
  28. Fermi GRB 251113A: Global MASTER-Net observations report
  29. GRB 251113A: BALROG localization (Fermi Trigger 784748255 / GRB 251113734)
  30. GRB 251113A: Fermi GBM Final Real-time Localization
  31. Fermi Gamma-ray Burst Monitor trigger 784717756/251113381 is not a GRB
  32. Fermi Gamma-ray Burst Monitor trigger 784687703/251113034 is not a GRB
  33. Fermi Gamma-ray Burst Monitor trigger 784687099/251113027 is not a GRB
  34. LIGO/Virgo/KAGRA S251112cm: Upper limits from Fermi-GBM Observations
  35. Fermi trigger No 784621743: Global MASTER-Net observations report
  36. Fermi Gamma-ray Burst Monitor trigger 784653403/251112637 is not a GRB
  37. GRB 251013C: Chandra X-ray observations and jet break detection
  38. GRB 251105B: Insight-HXMT/HE detection
  39. GRB 251105A: AstroSat CZTI detection
  40. GRB 251108A: Fermi GBM Final Localization Correction
  41. Fermi trigger No 784329591: Global MASTER-Net observations report
  42. Fermi trigger No 784279167: Global MASTER-Net observations report
  43. GRB 251102B: SVOM/GRM observation
  44. Fermi Gamma-ray Burst Monitor trigger 784279167/251108305 is not a GRB
  45. IPN triangulation of GRB 251105B (possible sGRB with EE)
  46. GRB 251106A: Kilonova-Catcher optical upper limit
  47. Fermi GBM Sub-Threshold Detection of GRB 251106A
  48. GRB 251103B: AstroSat CZTI detection
  49. GRB 251025C: TERI Gamma-ray detection
  50. GRB 251016B: TERI Gamma-ray detection
  51. GRB 251016A: TERI Gamma-ray detection of a short burst
  52. GRB 250920C: TERI Gamma-ray detection
  53. Fermi trigger No 784034269: Global MASTER-Net observations report
  54. Fermi Gamma-ray Burst Monitor trigger 784109140/251106337 is not a GRB
  55. GRB 251105A: Fermi GBM Observation
  56. GRB 251105C: Fermi GBM Final Localization Correction
  57. GRB 251105A: Swift/BAT-GUANO localization skymap of a burst
  58. GRB 251105B: AstroSat CZTI detection of a short burst with extended emission
  59. GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
  60. Fermi GBM Sub-Threshold Detection of GRB 251105B
  61. Fermi GRB 251105A: Global MASTER-Net observations report
  62. GRB 251105A: Fermi GBM Final Real-time Localization
  63. Fermi Gamma-ray Burst Monitor trigger 783986701/251104920 is not a GRB
  64. GRB 251103B: Fermi GBM observation
  65. GRB 251028A: Insight-HXMT/HE detection
  66. GRB 251103A: WFST optical observations
  67. GRB 251103A: OHP/T193 optical observations
  68. GRB 251103A: Xinglong 2.16m optical detection
  69. GRB 251103A: Insight-HXMT detection
  70. GRB 251103A: KAIT optical observations
  71. GRB 251103B: Nanshan/HMT optical upper limit
  72. GRB 251013C: 7DT detection and Medium-band SED of Afterglow
  73. GRB 251103A: Swift/BAT-GUANO arcminute localization of a burst
  74. GRB 251103B: MITSuME Akeno optical upper limits
  75. Fermi GRB 251103A: Global MASTER-Net observations report
  76. GRB 251103A: J-band detection with WINTER
  77. GRB 251103B: GROWTH-India Telescope optical upper limits
  78. GRB 251103A: Kilonova-Catcher optical afterglow detection
  79. GRB 251103B: Fermi GBM Final Real-time Localization
  80. GRB 251103A: Fermi GBM Observation
  81. GRB 251103A: SVOM/GRM observation
  82. GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
  83. GRB 251103A: GOTO optical afterglow detection
  84. GRB 251102A: AstroSat CZTI detection
  85. GRB 251103A: NOT spectroscopic redshift z = 0.76
  86. GRB 251103A: Fermi GBM Final Localization
  87. GRB 251102B: Fermi GBM Final Real-time Localization
  88. Fermi GRB 251102A: Global MASTER-Net observations report
  89. GRB 251102A: Fermi GBM Final Real-time Localization
  90. GRB 251031A: Fermi GBM Observation
  91. GRB 251031A: Swift/BAT-GUANO localization skymap of a burst
  92. Konus-Wind detection of GRB 251028A
  93. GRB 251031A: BALROG localization (Fermi Trigger 783588065 / GRB 251031306)
  94. GRB 251031A: Fermi GBM Final Real-time Localization
  95. GRB 251025C: SVOM/GRM observation
  96. GRB 251028A: GECAM-B detection
  97. GRB 251028A: SVOM/GRM observation
  98. GRB 251028A: Fermi GBM Observation
  99. GRB 251022A: Swift-XRT confirmation of fading
  100. GRB 251026B: LBT near-infrared observations

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