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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"

39458 results found.

  1. GRB 211106A: HST Observations
  2. GRB 211106A: Chandra Observations
  3. GRB 211129A: Fermi GBM observation
  4. Swift GRB 211129A: Global MASTER-Net observations report
  5. GRB 211129A: Nanshan/NEXT optical upper limit
  6. GRB 211129A: Enhanced Swift-XRT position
  7. IPN triangulation of GRB 211118A
  8. GRB 211129A: MITSuME Akeno optical upper limits
  9. GRB 211129A: Swift detection of a burst
  10. IceCube-211125A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  11. GRB 211023A: Xinglong 2.16m optical observations
  12. GRB 211023A: Xinglong 2.16m optical observations
  13. Fermi-LAT Gamma-ray Observations of IceCube-211125A
  14. GRB 211120548: Fermi GBM observation
  15. Konus-Wind detection of GRB 211120A
  16. IPN triangulation of GRB 211120A
  17. Chandra observations of GRB 210905A
  18. IceCube-211125A: IceCube observation of a high-energy neutrino candidate track-like event
  19. GRB 211118A: Fermi GBM detection
  20. IceCube Alert 211125.27: Global MASTER-Net observations report
  21. Fermi-LAT Gamma-ray Observations of IceCube-211123A
  22. IceCube-211123A: Upper limits from Fermi-GBM Observations
  23. IPN triangulation of GRB 211124A (short)
  24. HAWC-211123A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  25. GRB 211124A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  26. IceCube Alert 211123.60: Global MASTER-Net observations report
  27. IceCube-211123A - IceCube observation of a high-energy neutrino candidate track-like event
  28. Fermi trigger No 659413798: Global MASTER-Net observations report
  29. Trigger_21473: Tiled Swift observations
  30. GRB 211023B: LBT likely spectroscopic redshift of the host galaxy
  31. GRB 211120A: AGILE detection
  32. GRB 211120A: AstroSat CZTI detection
  33. Fermi trigger No 659183098: Global MASTER-Net observations report
  34. Fermi trigger No 659106591: Global MASTER-Net observations report
  35. GRB 211120B: Swift/BAT-GUANO detection outside the coded FOV
  36. GRB 211120A: GECAM detection
  37. GRB 211118A: AstroSat CZTI detection
  38. GRB 211023A: optical observations and photometric evidence of supernova
  39. Fermi-LAT Gamma-ray Observations of IceCube-211117A
  40. GRB211118A: Swift/BAT-GUANO detection outside the coded FOV
  41. Fermi trigger No 658971499: Global MASTER-Net observations report
  42. Fermi-LAT Gamma-ray Observations of IceCube-211116A
  43. IceCube Alert 211116.44: Global MASTER-Net observations report
  44. Fermi trigger No 658755664: Global MASTER-Net observations report
  45. Fermi trigger No 658764238: Global MASTER-Net observations report
  46. Konus-Wind detection of GRB 211107B
  47. IceCube-211116A : IceCube observation of a high-energy neutrino candidate track-like event
  48. GRB 211115A: CALET Gamma-Ray Burst Monitor detection
  49. Fermi trigger No 658686687: Global MASTER-Net observations report
  50. GRB 211115A: MAXI/GSC detection
  51. GRB 211023A: classification and SPI-ACS/INTEGRAL registration
  52. Fermi GRB 211112A: Global MASTER-Net observations report
  53. GRB 211106A: Swift/UVOT upper limits
  54. IPN triangulation of GRB 211106A (short)
  55. GRB 211112A: Fermi GBM Final Real-time Localization
  56. GRB 211110A: AstroSat CZTI detection
  57. Short GRB 211106A: spectroscopy of galaxies in the field
  58. GRB 211110A: GECAM detection
  59. Fermi trigger No 658214822: Global MASTER-Net observations report
  60. GRB 211107B: Swift-XRT afterglow detection
  61. GRB 211107A: GECAM detection
  62. GRB 211106A: VLT/FORS2 optical observations
  63. GRB 211106A, GROND observations
  64. GRB 211106A: Swift-XRT afterglow detection
  65. Fermi GRB 211109B: Global MASTER-Net observations report
  66. GRB 211023A: SAO RAS optical observations
  67. GRB 211107B: Swift-XRT observations
  68. MeerLICHT follow-up of GRB 211106A
  69. GRB 211109C: GECAM detection
  70. GRB 211107B: Swift ToO observations
  71. GRB 211109B: Fermi GBM Final Real-time Localization
  72. Fermi GRB 211109A: Global MASTER-Net observations report
  73. GRB 211109A: Fermi GBM Final Real-time Localization
  74. GRB 211107B: Swift/BAT detection
  75. GRB 211023A: A BdHN of type I
  76. Fermi GBM Sub-Threshold Detection of GRB 211106A
  77. Konus-Wind detection of GRB 211106A
  78. GRB 211023A: BTA spectroscopic redshift
  79. GRB 211107A: Fermi GBM Final Real-time Localization
  80. GRB 211106A: Swift-XRT observations
  81. GRB 211106A: Swift ToO observations
  82. GRB 211106A: Swift/BAT-GUANO candidate arcminute localization of a short burst
  83. GRB 211105A: MASTER optical inspection
  84. GRB 211105A: Swift/BAT-GUANO detection outside the coded FOV
  85. GRB 211105A: GECAM detection
  86. Swift Trigger 1082569 is probably not a GRB
  87. GRB 211105A: AGILE detection of a burst
  88. Fermi GBM trigger 657780594/211105201 is not a GRB
  89. GRB 211023A: optical detection by SBT in Ondrejov
  90. GRB 211023A: continued 1.3m DFOT Optical Observations and possible jet break
  91. Fermi trigger No 657742914: Global MASTER-Net observations report
  92. GRB 211104A: Fermi GBM Final Real-time Localization
  93. GRB 211023B: Subaru optical observation
  94. GRB 211024A: MITSuME Akeno optical observation
  95. GRB 211102B: GECAM detection
  96. Fermi GRB 211102A: Global MASTER-Net observations report
  97. GRB 211102B: BALROG localization (Fermi Trigger 657554740 / GRB 211102587)
  98. GRB 211102B: Fermi GBM Final Real-time Localization
  99. GRB 211023B: MITSuME Akeno optical upper limits
  100. GRB 211102A: BALROG localization (Fermi Trigger 657533168 / GRB 211102338)

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