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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"

36254 results found.

  1. GRB 260926C: GECAM-B observation
  2. GRB 260926A: GECAM-B observation
  3. GRB 260926B: Glowbug gamma-ray detection of a likely short burst
  4. GRB 260926A: Glowbug gamma-ray detection
  5. GRB 260924A: VLA detection
  6. GRB 260924A: Swift/UVOT UV grism spectrum results
  7. GRB 260924A: AbAO optical observations
  8. Fermi GRB 260928A: Global MASTER-Net observations report
  9. GRB 260928A: Fermi GBM Final Real-time Localization
  10. GRB 260925A: Swift-BAT refined analysis
  11. GRB 260924A: Upper limits from a neutrino search with IceCube
  12. Fermi GRB 260926C: Global MASTER-Net observations report
  13. GRB 260926C: Fermi GBM Final Real-time Localization
  14. GRB260914A: MAO/AZT-22 optical observations
  15. GRB 260926B: Fermi GBM Final Real-time Localization
  16. Fermi GRB 260926A: Global MASTER-Net observations report
  17. GRB 260924A: Near-infrared detection with MDM/MIRAGE
  18. GRB 260926A: Fermi GBM Final Real-time Localization
  19. GRB 260924A: COLIBRÍ optical observations
  20. GRB 260924A: Second-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  21. GRB 260925A: J-band upper limit by SYSU 80cm infrared telescope
  22. GRB 260925A: Swift-XRT refined Analysis
  23. Swift Trigger 1513439 is probably not a GRB
  24. GRB 260925A: Swift/UVOT Upper Limits
  25. Konus-Wind detection of GRB 260924A
  26. GRB 260924A: Extreme Isotropic-equivalent Gamma-ray Energy and encouragement for multiwavelength follow-up observations
  27. GRB 260923A: Glowbug gamma-ray detection
  28. GRB 260924A: Optical follow-up observations with Kinder
  29. GRB 260922A: Glowbug gamma-ray detection
  30. GRB 260925A: Enhanced Swift-XRT position
  31. GRB 260925A: COLIBRÍ optical upper limits
  32. GRB 260925A: FRAM-Auger optical limit
  33. GRB 260924A: Ondrejov D50 optical afterglow detection
  34. GRB 260924A: SVOM/GRM observation
  35. GRB 260924A: 2.2m CAHA spectroscopic redshift z = 3.51
  36. GRB 260925A: Swift detection of a burst
  37. GRB 260923A: Insight-HXMT/HE detection
  38. GRB 260924A: J-band observations by the SYSU 80 cm infrared telescope
  39. GRB 260924A: Swift/UVOT Detection
  40. GRB 260924A: GROWTH-India Telescope optical observations
  41. GRB 260924A: Swift-BAT refined analysis
  42. GRB 260924A: NuSTAR detection of prompt emission
  43. GRB 260924A: Swift/UVOT Upper Limits
  44. GRB 260924A: Swift-XRT refined Analysis
  45. Konus-Wind detection of GRB 260922A
  46. GRB 260922A: NuSTAR detection of prompt emission
  47. GRB 260921A: NuSTAR detection of prompt emission
  48. Konus-Wind detection of GRB 260921A (correction to GCN 45722)
  49. GRB 260921A: SVOM/GRM observation
  50. GRB 260922A: COLIBRÍ Confirmation of the Optical Counterpart
  51. GRB 260924A: Fermi GRB Observation
  52. Konus-Wind detection of GRB 260921A (possible merger-origin)
  53. GRB 260924A: Fermi-LAT detection of a bright burst
  54. GRB 260924A: AstroSat CZTI detection
  55. GRB 260920A: SVOM/GRM observation
  56. GRB 260924A: NOT optical counterpart confirmation
  57. GRB 260924A: detection of a bright optical afterglow by the 1.5m OSN telescope
  58. GRB 260922A: CALET Gamma-Ray Burst Monitor detection
  59. GRB 260924A: Enhanced Swift-XRT position
  60. GRB 260924A: Swift detection of a burst
  61. GRB 260924A: Fermi GBM Final Real-time Localization
  62. Fermi GRB 260923A: Global MASTER-Net observations report
  63. GRB 260923A: Fermi GBM Final Real-time Localization
  64. Trigger_21914: Swift ToO observations (retracted)
  65. GRB 260922A: Ondrejov D50 optical limit
  66. ATCA observations of GRB 260909A
  67. GRB 260922A: Swift-BAT refined analysis
  68. GRB 260922A: J-band upper limit with WINTER
  69. GRB 260922A: Swift/UVOT Upper Limits
  70. GRB 260922A: COLIBRÍ Optical Counterpart Candidate (correction to GCN 45698)
  71. GRB 260922A: COLIBRÍ optical upper limits
  72. GRB 260922A: Swift-XRT refined Analysis
  73. GRB 260922A: Enhanced Swift-XRT position
  74. Konus-Wind detection of GRB 260810A
  75. GRB 260920A: Glowbug gamma-ray detection
  76. GRB 260918A: SVOM/ECLAIRs refined analysis
  77. GRB 260922A: SVOM/C-GFT optical upper limit
  78. GRB 260922A: Swift detection of a burst
  79. GRB 260917C: AstroSat CZTI detection
  80. GRB 260920B/EP260920b: GECAM-B detection of a burst
  81. GRB 260921A: AstroSat CZTI detection
  82. GRB 260921A: Swift-BAT refined analysis
  83. GRB 260921B: Fermi GBM Final Localization
  84. GRB 260921A: Fermi GBM Observation
  85. GRB 260917B:: SVOM/ECLAIRs refined analysis
  86. Swift GRB 260921A: MASTER OT J094129.58+025052.5 possible optical counterpart detection with host galaxy (z=1.3)
  87. Swift GRB 260921A: Global MASTER-Net observations report
  88. GRB 260921A: Swift detection of a burst
  89. GRB 260921A: Fermi GBM Final Real-time Localization
  90. GRB 260920A: AstroSat CZTI detection
  91. IceCube-260919A: Upper limits from a search for additional neutrino events in IceCube
  92. GRB 260920A: Fermi GBM Final Real-time Localization
  93. GRB 260915A: VLT optical and near-infrared upper limits
  94. IceCube-260919A - IceCube observation of a high-energy neutrino candidate track-like event
  95. GRB 260918A: SVOM/C-GFT optical upper limits
  96. Fermi GBM Sub-Threshold Detection of GRB 260918A
  97. Konus-Wind detection of GRB 260916B (short/hard)
  98. GRB 260918A: SVOM/VT optical upper limits
  99. GRB 260916B: Glowbug gamma-ray detection of a short burst
  100. GRB 260918A: EP-FXT follow-up observation

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