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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"

37645 results found.

  1. EP trigger 01709320908: Ondrejov D50 observation, fading star suggests stellar flare
  2. GRB 261005B: Swift detection of a burst
  3. GRB 261005A: Fermi GBM Final Real-time Localization
  4. GRB 261003A: Glowbug gamma-ray detection of a likely short burst
  5. GRB 261002A: Fermi GBM Final Localization
  6. GRB 260930B: SVOM/GRM observation
  7. Konus-Wind detection of GRB 260919A / EP 260920a
  8. GRB 260921B: GECAM-B observation
  9. GRB 260930B: GECAM-B detection of a burst
  10. Trigger_21915: Swift ToO observations (retracted)
  11. Fermi GRB 261003A: Global MASTER-Net observations report
  12. GRB 261003A: Fermi GBM Final Real-time Localization
  13. Fermi-LAT Gamma-ray Observations of IceCube-260930A
  14. Fermi GBM Detection of GRB 260919A / EP260920a
  15. IPN triangulation of GRB 260919A / EP260920a
  16. Fermi GRB 260930B: Global MASTER-Net observations report
  17. GRB 260926C: SVOM/GRM observation
  18. GRB 260930B: Fermi GBM Final Real-time Localization
  19. GRB 260930A: Fermi GBM Final Real-time Localization
  20. IceCube-260930A - IceCube observation of a high-energy neutrino candidate track-like event
  21. GRB 260926C: AstroSat CZTI detection
  22. GRB 260926C: GECAM-B observation
  23. GRB 260926A: GECAM-B observation
  24. GRB 260926B: Glowbug gamma-ray detection of a likely short burst
  25. GRB 260926A: Glowbug gamma-ray detection
  26. GRB 260924A: VLA detection
  27. GRB 260924A: Swift/UVOT UV grism spectrum results
  28. GRB 260924A: AbAO optical observations
  29. Fermi GRB 260928A: Global MASTER-Net observations report
  30. GRB 260928A: Fermi GBM Final Real-time Localization
  31. GRB 260925A: Swift-BAT refined analysis
  32. GRB 260924A: Upper limits from a neutrino search with IceCube
  33. Fermi GRB 260926C: Global MASTER-Net observations report
  34. GRB 260926C: Fermi GBM Final Real-time Localization
  35. GRB260914A: MAO/AZT-22 optical observations
  36. GRB 260926B: Fermi GBM Final Real-time Localization
  37. Fermi GRB 260926A: Global MASTER-Net observations report
  38. GRB 260924A: Near-infrared detection with MDM/MIRAGE
  39. GRB 260926A: Fermi GBM Final Real-time Localization
  40. GRB 260924A: COLIBRÍ optical observations
  41. GRB 260924A: Second-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  42. GRB 260925A: J-band upper limit by SYSU 80cm infrared telescope
  43. GRB 260925A: Swift-XRT refined Analysis
  44. Swift Trigger 1513439 is probably not a GRB
  45. GRB 260925A: Swift/UVOT Upper Limits
  46. Konus-Wind detection of GRB 260924A
  47. GRB 260924A: Extreme Isotropic-equivalent Gamma-ray Energy and encouragement for multiwavelength follow-up observations
  48. GRB 260923A: Glowbug gamma-ray detection
  49. GRB 260924A: Optical follow-up observations with Kinder
  50. GRB 260922A: Glowbug gamma-ray detection
  51. GRB 260925A: Enhanced Swift-XRT position
  52. GRB 260925A: COLIBRÍ optical upper limits
  53. GRB 260925A: FRAM-Auger optical limit
  54. GRB 260924A: Ondrejov D50 optical afterglow detection
  55. GRB 260924A: SVOM/GRM observation
  56. GRB 260924A: 2.2m CAHA spectroscopic redshift z = 3.51
  57. GRB 260925A: Swift detection of a burst
  58. GRB 260923A: Insight-HXMT/HE detection
  59. GRB 260924A: J-band observations by the SYSU 80 cm infrared telescope
  60. GRB 260924A: Swift/UVOT Detection
  61. GRB 260924A: GROWTH-India Telescope optical observations
  62. GRB 260924A: Swift-BAT refined analysis
  63. GRB 260924A: NuSTAR detection of prompt emission
  64. GRB 260924A: Swift/UVOT Upper Limits
  65. GRB 260924A: Swift-XRT refined Analysis
  66. Konus-Wind detection of GRB 260922A
  67. GRB 260922A: NuSTAR detection of prompt emission
  68. GRB 260921A: NuSTAR detection of prompt emission
  69. Konus-Wind detection of GRB 260921A (correction to GCN 45722)
  70. GRB 260921A: SVOM/GRM observation
  71. GRB 260922A: COLIBRÍ Confirmation of the Optical Counterpart
  72. GRB 260924A: Fermi GRB Observation
  73. Konus-Wind detection of GRB 260921A (possible merger-origin)
  74. GRB 260924A: Fermi-LAT detection of a bright burst
  75. GRB 260924A: AstroSat CZTI detection
  76. GRB 260920A: SVOM/GRM observation
  77. GRB 260924A: NOT optical counterpart confirmation
  78. GRB 260924A: detection of a bright optical afterglow by the 1.5m OSN telescope
  79. GRB 260922A: CALET Gamma-Ray Burst Monitor detection
  80. GRB 260924A: Enhanced Swift-XRT position
  81. GRB 260924A: Swift detection of a burst
  82. GRB 260924A: Fermi GBM Final Real-time Localization
  83. Fermi GRB 260923A: Global MASTER-Net observations report
  84. GRB 260923A: Fermi GBM Final Real-time Localization
  85. Trigger_21914: Swift ToO observations (retracted)
  86. GRB 260922A: Ondrejov D50 optical limit
  87. Fermi-LAT Gamma-ray Observations of IceCube-260919A
  88. Fermi-LAT Gamma-ray Observations of IceCube-260916A
  89. ATCA observations of GRB 260909A
  90. GRB 260922A: Swift-BAT refined analysis
  91. GRB 260922A: J-band upper limit with WINTER
  92. GRB 260922A: Swift/UVOT Upper Limits
  93. GRB 260922A: COLIBRÍ Optical Counterpart Candidate (correction to GCN 45698)
  94. GRB 260922A: COLIBRÍ optical upper limits
  95. GRB 260922A: Swift-XRT refined Analysis
  96. GRB 260922A: Enhanced Swift-XRT position
  97. Fermi-LAT Gamma-ray Observations of IceCube-260805A
  98. Konus-Wind detection of GRB 260810A
  99. GRB 260920A: Glowbug gamma-ray detection
  100. GRB 260918A: SVOM/ECLAIRs refined analysis

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