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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"

36179 results found.

  1. Swift GRB 211129A: Global MASTER-Net observations report
  2. GRB 211129A: Nanshan/NEXT optical upper limit
  3. GRB 211129A: Enhanced Swift-XRT position
  4. IPN triangulation of GRB 211118A
  5. GRB 211129A: MITSuME Akeno optical upper limits
  6. GRB 211129A: Swift detection of a burst
  7. IceCube-211125A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  8. GRB 211023A: Xinglong 2.16m optical observations
  9. GRB 211023A: Xinglong 2.16m optical observations
  10. GRB 211120548: Fermi GBM observation
  11. Konus-Wind detection of GRB 211120A
  12. IPN triangulation of GRB 211120A
  13. Chandra observations of GRB 210905A
  14. GRB 211118A: Fermi GBM detection
  15. IceCube-211123A: Upper limits from Fermi-GBM Observations
  16. IPN triangulation of GRB 211124A (short)
  17. HAWC-211123A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  18. GRB 211124A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  19. GRB 211023B: LBT likely spectroscopic redshift of the host galaxy
  20. GRB 211120A: AGILE detection
  21. GRB 211120A: AstroSat CZTI detection
  22. GRB 211120B: Swift/BAT-GUANO detection outside the coded FOV
  23. GRB 211120A: GECAM detection
  24. GRB 211118A: AstroSat CZTI detection
  25. GRB 211023A: optical observations and photometric evidence of supernova
  26. GRB211118A: Swift/BAT-GUANO detection outside the coded FOV
  27. Konus-Wind detection of GRB 211107B
  28. GRB 211115A: CALET Gamma-Ray Burst Monitor detection
  29. GRB 211115A: MAXI/GSC detection
  30. GRB 211023A: classification and SPI-ACS/INTEGRAL registration
  31. Fermi GRB 211112A: Global MASTER-Net observations report
  32. GRB 211106A: Swift/UVOT upper limits
  33. IPN triangulation of GRB 211106A (short)
  34. GRB 211112A: Fermi GBM Final Real-time Localization
  35. GRB 211110A: AstroSat CZTI detection
  36. Short GRB 211106A: spectroscopy of galaxies in the field
  37. GRB 211110A: GECAM detection
  38. GRB 211107B: Swift-XRT afterglow detection
  39. GRB 211107A: GECAM detection
  40. GRB 211106A: VLT/FORS2 optical observations
  41. GRB 211106A, GROND observations
  42. GRB 211106A: Swift-XRT afterglow detection
  43. Fermi GRB 211109B: Global MASTER-Net observations report
  44. GRB 211023A: SAO RAS optical observations
  45. GRB 211107B: Swift-XRT observations
  46. MeerLICHT follow-up of GRB 211106A
  47. GRB 211109C: GECAM detection
  48. GRB 211107B: Swift ToO observations
  49. GRB 211109B: Fermi GBM Final Real-time Localization
  50. Fermi GRB 211109A: Global MASTER-Net observations report
  51. GRB 211109A: Fermi GBM Final Real-time Localization
  52. GRB 211107B: Swift/BAT detection
  53. GRB 211023A: A BdHN of type I
  54. Fermi GBM Sub-Threshold Detection of GRB 211106A
  55. Konus-Wind detection of GRB 211106A
  56. GRB 211023A: BTA spectroscopic redshift
  57. GRB 211107A: Fermi GBM Final Real-time Localization
  58. GRB 211106A: Swift-XRT observations
  59. GRB 211106A: Swift ToO observations
  60. GRB 211106A: Swift/BAT-GUANO candidate arcminute localization of a short burst
  61. GRB 211105A: MASTER optical inspection
  62. GRB 211105A: Swift/BAT-GUANO detection outside the coded FOV
  63. GRB 211105A: GECAM detection
  64. Swift Trigger 1082569 is probably not a GRB
  65. GRB 211105A: AGILE detection of a burst
  66. Fermi GBM trigger 657780594/211105201 is not a GRB
  67. GRB 211023A: optical detection by SBT in Ondrejov
  68. GRB 211023A: continued 1.3m DFOT Optical Observations and possible jet break
  69. GRB 211104A: Fermi GBM Final Real-time Localization
  70. GRB 211023B: Subaru optical observation
  71. GRB 211024A: MITSuME Akeno optical observation
  72. GRB 211102B: GECAM detection
  73. Fermi GRB 211102A: Global MASTER-Net observations report
  74. GRB 211102B: BALROG localization (Fermi Trigger 657554740 / GRB 211102587)
  75. GRB 211102B: Fermi GBM Final Real-time Localization
  76. GRB 211023B: MITSuME Akeno optical upper limits
  77. GRB 211102A: BALROG localization (Fermi Trigger 657533168 / GRB 211102338)
  78. GRB 211102A: Fermi GBM Final Real-time Localization
  79. GRB 211024B: Optical afterglow observation by Ondrejov D50
  80. GRB 211024A: 1.3m DFOT observations
  81. Fermi GRB 211031A: Global MASTER-Net observations report
  82. GRB 211031A: Fermi GBM Final Real-time Localization
  83. IPN triangulation of GRB 211022A
  84. GRB 211023A: 1.3m DFOT Optical Observations
  85. Konus-Wind detection of GRB 211023A
  86. GRB 2121023B: 6 GHz VLA radio upper limit
  87. GRB 211023A: Terskol optical observations
  88. GRB 211023A: continued Mondy optical observations
  89. GRB 211024A: Swift-XRT source 4 is not an afterglow.
  90. GRB 211023B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  91. Fermi GRB 211027A: Global MASTER-Net observations report
  92. GRB 211024A: Possible afterglow candidate from GIT
  93. GRB 211024A: Swift-XRT observations
  94. GRB 211027A: Fermi GBM Final Real-time Localization
  95. GRB 211024A: Fermi GBM detection
  96. GRB 211018A: Swift-XRT observations
  97. GRB 211025A: Optical Afterglow Detection
  98. GRB 211024A: Swift ToO observations
  99. GRB 211024A: Swift/BAT-GUANO detection and candidate arcminute localization of a short burst
  100. GRB 211024B: Swift/UVOT detection

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