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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"

12169 results found.

  1. GRB 210822A: TSHAO optical observation
  2. Swift detection of an outburst from SGR Swift J1555.2-5402
  3. GRB 210824A: Swift-XRT refined Analysis
  4. GRB 210824A: Swift detection of a burst
  5. GRB 210822A: GECAM refined analysis
  6. Konus-Wind detection of GRB 210822A
  7. GRB 210822A: AstroSat CZTI detection
  8. GRB 210822A: Swift-BAT refined analysis
  9. GRB 210820A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  10. GRB 210822A: Fermi-LAT detection
  11. Fermi GRB 210822B: Global MASTER-Net observations report
  12. GRB 210822A: KAIT Optical Afterglow Confirmation
  13. GRB 210820A: LCO Optical Upper Limit
  14. GRB 210820A: Nanshan/NEXT optical upper limit
  15. GRB 210820A: Swift-XRT refined Analysis
  16. Swift GRB 210820A: Global MASTER-Net observations report
  17. GRB 210820B: Fermi GBM Final Localization
  18. Fermi trigger No 651110719: Global MASTER-Net observations report
  19. Konus-Wind detection of GRB 210818A
  20. GRB 210818A: AstroSat CZTI detection
  21. GRB 210818A: AGILE detection
  22. Fermi trigger No 650687034: Global MASTER-Net observations report
  23. Fermi-LAT Gamma-ray Observations of IceCube-210811A
  24. GRB 210807A: continued Assy, AbAO and Mondy observations
  25. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  26. GRB 210730A: Tautenburg observations
  27. GRB 210807A: Tautenburg observations
  28. IceCube Alert 210811.09: Global MASTER-Net observations report
  29. GRB 210807C: Swift-BAT refined analysis
  30. GRB 210610B: Assy optical observations
  31. Fermi GRB 210807C: Global MASTER-Net observations report
  32. Swift GRB210807.96: Global MASTER-Net observations report
  33. GRB 210807C: Swift detection of a burst
  34. Fermi GRB 210807B: Global MASTER-Net observations report
  35. Swift GRB210807.78: Global MASTER-Net observations report
  36. GRB 210807A: BOOTES-5/JGT optical afterglow detection
  37. GRB 210807A: Swift detection of a burst with an optical counterpart
  38. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  39. IPN Triangulation of a bright burst from SGR 1935+2154
  40. Fermi trigger No 649814537: Global MASTER-Net observations report
  41. GRB 210802A: BOOTES-2/TELMA optical upper limit
  42. GRB 210802A: Fermi GBM detection
  43. GRB 210802A: Fermi-LAT detection
  44. Fermi trigger No 649627691: Global MASTER-Net observations report
  45. Swift GRB210731.62: Global MASTER-Net observations report
  46. GRB 210731A: MeerLICHT optical afterglow detection
  47. GRB210731A: Enhanced Swift-XRT position
  48. Swift GRB210731.93: Global MASTER-Net observations report
  49. Fermi-LAT Gamma-ray Observations of IceCube-210730A
  50. GRB 210730A: BOOTES-5/JGT and 2.2m CAHA telescopes optical limit
  51. Fermi trigger No 649390368: Global MASTER-Net observations report
  52. GRB 210730A: AstroSat CZTI detection
  53. GRB 210730A: Swift-XRT refined Analysis
  54. GRB 210727A: AstroSat CZTI detection
  55. GRB 210726A: Deep CAHA 2.2m limit
  56. GRB 210714A: Fermi GBM observation
  57. GRB 210726A: Swift-XRT refined Analysis
  58. GRB 210727A: AGILE/MCAL detection
  59. GRB 210726A: CAHA 2.2m telescope optical limit
  60. GRB 210726A: Swift detection of a burst
  61. Swift GRB210726.80: Global MASTER-Net observations report
  62. Fermi trigger No 648959581: Global MASTER-Net observations report
  63. GRB 210725B: Swift-XRT refined Analysis
  64. GRB 210724A: Zeiss-1000 of Koshka observatory, optical upper limit
  65. GRB 210725A: Swift-XRT refined Analysis
  66. GRB 210724A: Swift-XRT refined Analysis
  67. GRB 210722A: continued Assy optical observations
  68. GRB 210722A: Nanshan/NEXT further optical observations
  69. Fermi trigger No 648868114: Global MASTER-Net observations report
  70. GRB 210725A: Swift detection of a burst
  71. GRB210724A: MeerLICHT upper limits
  72. GRB 210724A: Swift detection of a burst
  73. Swift GRB210724.84: Global MASTER-Net observations report
  74. GRB 210722A: continued Assy optical observations
  75. GRB 210722A: D50 optical detection
  76. GRB 210722A: Fermi GBM observation
  77. GRB 210722A: Swift-BAT refined analysis
  78. GRB 210722A: Kitab optical observations, light curve
  79. GRB 210723A: Swift detection of a burst
  80. GRB 210722A: Swift-XRT refined Analysis
  81. GRB 210722A: Swift/UVOT Detection
  82. GRB 210722A: GIT optical detection and preliminary analysis
  83. GRB 210702A: ALMA detection of mm-band rebrightening
  84. GRB 210722A: Assy optical detection
  85. GRB 210722A: Nanshan/NEXT optical afterglow observations
  86. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  87. Fermi trigger No 648602917: Global MASTER-Net observations report
  88. Fermi-LAT Gamma-ray Observations of IceCube-210717A
  89. Fermi trigger No 648278666: Global MASTER-Net observations report
  90. Konus-Wind detection of GRB 210714A
  91. Fermi trigger No 648033323: Global MASTER-Net observations report
  92. Fermi trigger No 648024201: Global MASTER-Net observations report
  93. GRB 210712A: Swift-BAT refined analysis
  94. GECAM detection of a short burst from SGR J1935+2154
  95. Recent activity of SGR 1935+2154 as observed by CGBM
  96. GRB 210712A: Swift-XRT refined Analysis
  97. Fermi trigger No 647805873: Global MASTER-Net observations report
  98. GRB 210704A: classification as long GRB and redshift estimating
  99. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  100. GECAM detection of a short burst from SGR J1935+2154

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