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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"

24417 results found.

  1. LIGO/Virgo/KAGRA S251013x: Updated Sky localization and Source Classification
  2. GRB 251013B: SVOM/GRM observation
  3. GRB 251013A: SVOM/GRM observation
  4. GRB 251013B: Fermi GBM Final Real-time Localization
  5. Fermi GRB 251013A: Global MASTER-Net observations report
  6. GRB 251013A: Fermi GBM Final Real-time Localization
  7. LIGO/Virgo/KAGRA S251013x: Identification of a GW compact binary merger candidate
  8. GRB 251011B inspection: MASTER orphan GRB detection
  9. Fermi GRB 251011A: Global MASTER-Net observations report
  10. GRB 251012A: Fermi GBM Final Real-time Localization
  11. GRB 251011B: SVOM/GRM observation
  12. GRB 251011B: Fermi GBM Observation
  13. GRB 251011C: Fermi GBM Final Real-time Localization
  14. GRB 251011B: Swift detection of a burst
  15. GRB 251011B: Fermi GBM Final Real-time Localization
  16. GRB 251011A: Fermi GBM Final Real-time Localization
  17. GRB 251010A: Fermi GBM Final Real-time Localization
  18. GRB 251009A: GECAM-B detection of a short burst
  19. GRB 251009B (short): Glowbug gamma-ray detection
  20. GRB 251007A: Swift-BAT refined analysis
  21. GRB 251007A: SVOM/GRM observation
  22. GRB 251006A: CALET Gamma-Ray Burst Monitor detection
  23. GRB 251007B - SVOM/ECLAIRs refined analysis
  24. SVOM/sb25101004: SVOM detection of a stellar flare
  25. GRB 251009A: Fermi GBM Final Localization
  26. EP251006a: Global MASTER-Net observations report
  27. GRB 251006A: Fermi GBM Observation
  28. GRB 251002A - SVOM/ECLAIRs refined analysis
  29. IceCube alert 141456_888784 retraction
  30. IceCube Alert 251008A: Global MASTER-Net observations report
  31. GRB 251003A: Fermi GBM Observation
  32. GRB 251006B: Fermi GBM Observation
  33. GRB 251006B/EP251006a: EP-FXT afterglow detection
  34. EP250911a: Koshka Zeiss-1000 Optical Upper Limit
  35. GRB 251007B: SVOM/VT optical candidate
  36. GRB 251007A: Swift-XRT refined Analysis
  37. GRB 251007A: SVOM/C-GFT optical observations
  38. GRB 251005C: PRIME J-band upper limit
  39. Swift GRB 251007B: Global MASTER-Net observations report
  40. GRB 251007A: Glowbug gamma-ray detection
  41. GRB 251007B: SVOM/C-GFT upper limit
  42. Swift GRB 251007A: Global MASTER-Net observations report
  43. GRB 251007B: SVOM detection of a faint burst
  44. GRB 251007B: Swift detection of a burst
  45. GRB 251006A: Swift/BAT-GUANO subthreshold detection of a short burst
  46. GRB 251005B: Glowbug gamma-ray detection
  47. EP251003a: LCO and VST fading optical counterpart
  48. GRB 251006B/EP251006a: SVOM/VT optical candidate
  49. GRB 251006B/EP251006a: EP-FXT follow-up observation
  50. GRB 251006B: SVOM/GRM observation
  51. GRB 251006B/EP251006a: EP-WXT detection
  52. GRB 251005C: SVOM/VT optical fading
  53. GRB 251005C: SVOM/GRM observation of a likely short GRB
  54. LIGO/Virgo/KAGRA S251006dd: Identification of a GW compact binary merger candidate
  55. Fermi GRB 251006B: Global MASTER-Net observations report
  56. GRB 251006B: BALROG localization (Fermi Trigger 781473909 / GRB 251006837)
  57. GRB 251006B: Fermi GBM Final Real-time Localization
  58. Fermi GRB 251006A: Global MASTER-Net observations report
  59. GRB 251006A: Fermi GBM Final Real-time Localization
  60. GRB 251005C: SVOM/VT optical candidate
  61. GRB 250902A: MSU cubesats detection
  62. GRB 251005C: Fermi GBM Observation
  63. Swift GRB 251005A: Global MASTER-Net observations report
  64. Fermi trigger No 781367244: Global MASTER-Net observations report
  65. GRB 251005B: Fermi GBM Final Real-time Localization
  66. GRB 251005A: Fermi GBM Final Localization
  67. Fermi GBM Sub-Threshold Detection of GRB 250910A
  68. GRB 251003A: Swift-BAT refined analysis
  69. GRB 251002A: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  70. GRB 251003A: Swift-XRT refined Analysis
  71. GRB 251002A: Fermi GBM Observation
  72. LIGO/Virgo/KAGRA S251003at: Retraction of GW compact binary merger candidate
  73. GRB 251001C: SVOM/GRM observation
  74. GRB 251002A: SVOM/COLIBRÍ (FM-GFT) optical observations
  75. GRB 251002A: J band observations by SYSU 80cm infrared telescope
  76. GRB 251002A: OHP/T193 MISTRAL optical afterglow detection
  77. GRB 251002A: EP-FXT counterpart detection
  78. GRB 251003A: LCOGT Optical Detection
  79. GRB 251003A: Fermi GBM Final Real-time Localization
  80. Swift GRB251003A: Global MASTER-Net observations report
  81. Fermi/SVOM GRB 251002A : MASTER OT earlier detection in 2 polarization filters
  82. GRB 251002A: BOOTES-6 early optical detection
  83. GRB 251002A: LCO optical observation
  84. GRB 251002A: SVOM/VT optical observation
  85. GRB 251002A: SVOM detection of a burst
  86. Fermi GRB 251002A: Global MASTER-Net observations report
  87. GRB 251001B: Swift-BAT refined analysis
  88. GRB 251001A: SVOM/GRM observation
  89. GRB 251001B: SVOM/VT optical observation
  90. GRB 251001C: Glowbug gamma-ray detection
  91. Swift GRB 251001B: Global MASTER-Net observations report
  92. GRB 251001B: Fermi GBM Observation
  93. GRB 250930A: Fermi GBM Final Localization
  94. GRB 251001B: LCOGT Optical Observations
  95. GRB 250930A: SVOM/GRM observation
  96. GRB 251001B: GOTO optical counterpart detection
  97. GRB 251001B: Swift detection of a burst
  98. GRB 251001B: Fermi GBM Final Real-time Localization
  99. GRB 251001A: Fermi GBM Detection
  100. GRB 250910A / EP250910a: VLT limits on the possible associated supernova

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