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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"

27963 results found.

  1. GRB 210725B: Swift-XRT refined Analysis
  2. GRB 210725A: Fermi GBM detection
  3. GRB 210725A: Swift-XRT refined Analysis
  4. GRB 210725B: Swift-BAT refined analysis
  5. GRB 210724A: Swift-XRT refined Analysis
  6. GRB 210725A: Swift-BAT refined analysis
  7. GRB 210724A: Swift-BAT refined analysis
  8. Swift GRB 210725B: Global MASTER-Net observations report
  9. GRB 210725B: Enhanced Swift-XRT position
  10. GRB 210725A: MITSuME Akeno optical upper limits
  11. GRB 210725B: Swift detection of a burst
  12. GRB 210725A: CALET Gamma-Ray Burst Monitor detection
  13. GRB 210723A: CALET Gamma-Ray Burst Monitor detection
  14. GRB 210725A: KAIT Optical Upper Limit
  15. GRB 210725A: Swift detection of a burst
  16. Swift GRB210725.16: Global MASTER-Net observations report
  17. GRB 210723A: Fermi GBM Observation
  18. GRB210724A: MeerLICHT upper limits
  19. GRB 210724A: Swift detection of a burst
  20. Swift GRB210724.84: Global MASTER-Net observations report
  21. GRB 210723A: Swift-BAT refined analysis
  22. GRB 210723A: Swift-XRT refined Analysis
  23. GRB 210722A: D50 optical detection
  24. Swift GRB 210723A: Global MASTER-Net observations report
  25. GRB 210722A: Fermi GBM observation
  26. GRB 210722A: Swift-BAT refined analysis
  27. GRB 210722A: Redshift from OSIRIS/GTC
  28. GRB 210723A: Prompt enhanced Swift-XRT position
  29. GRB 210723A: Swift detection of a burst
  30. GRB 210722A: Swift-XRT refined Analysis
  31. GRB 210722A: Swift/UVOT Detection
  32. GRB 210722A: GIT optical detection and preliminary analysis
  33. Swift GRB 210722A: Global MASTER-Net observations report
  34. GRB 210702A: ALMA detection of mm-band rebrightening
  35. GRB 210722A: Assy optical detection
  36. GRB 210702A: ATCA detection of radio rebrightening
  37. GRB 210722A: Nanshan/NEXT optical afterglow observations
  38. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  39. GRB 210719A: GECAM detection
  40. IceCube-210717A: IceCube observation of a high-energy neutrino candidate track-like event
  41. Konus-Wind detection of GRB 210714A
  42. Fermi trigger No 647942198: MASTER optical afterglow detection
  43. GRB 210712A: Swift-BAT refined analysis
  44. GECAM detection of a short burst from SGR J1935+2154
  45. GRB 210712A: Swift-XRT refined Analysis
  46. GRB 210712A: Swift/UVOT Upper Limits
  47. GRB 210712A: BOOTES-3/YA optical upper limit
  48. GRB 210712A: Enhanced Swift-XRT position
  49. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  50. GECAM detection of a short burst from SGR J1935+2154
  51. GRB 210712A: Swift detection of a burst
  52. GRB 210709A: AstroSat CZTI detection
  53. GRB210704A: Gemini near-infrared upper limits
  54. GECAM detection of a short burst from SGR J1935+2154
  55. GRB 210704A: OSIRIS/GTC Observations and Archival Detection of the Possible Host Galaxy
  56. GRB 210704A: Gemini-North Infrared Source Detection
  57. GRB 210706A: Swift/XRT afterglow confirmation
  58. GECAM detection of a short burst from SGR 1935+2154
  59. GRB 210708B: Swift-BAT refined analysis
  60. GRB 210709A: Fermi GBM Final Real-time Localization
  61. Swift GRB 210708B: Global MASTER-Net observations report
  62. GRB 210708A: Swift/UVOT Upper Limits
  63. GRB 210702A: ATCA detection
  64. GRB 210702A: ALMA detection
  65. GRB 210708A: Swift-BAT refined analysis
  66. Fermi GBM Sub-Threshold Detection of GRB 210708A
  67. Fermi GBM Sub-Threshold Detection of GRB 210707A
  68. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  69. GRB 210708B: Swift detection of a possible burst
  70. GRB 210708A: Swift-XRT refined Analysis
  71. GECAM detection of a short burst from SGR 1935+2154
  72. GRB 210708A: Swift detection of a burst
  73. Swift GRB210708.10: Global MASTER-Net observations report
  74. GRB 210704A: CAHA 2.2m telescope optical limit
  75. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  76. Fermi GBM Observations of SGR J1935+2154
  77. Swift-BAT detection of a burst from SGR 1935+2154
  78. GRB 210706A: Fermi GBM observation
  79. GRB 210706A: optical upper limit of Sintesz-Newton/CrAO and AS-32/AbAO
  80. Konus-Wind detection of GRB 210706A
  81. GRB 210706A: GIT optical upper limits
  82. GRB 210704A: OAJ T80 multi-color detections
  83. GECAM detection of a bright short burst from SGR 1935+2154
  84. GRB 210706A: Swift-XRT afterglow detection
  85. GRB 210706A: Swift ToO observations
  86. INTEGRAL detection of a burst from SGR 1935+2154
  87. GRB 210706A: Swift/BAT-GUANO detection and arcminute localization
  88. GRB 210704A: OSIRIS/GTC spectroscopy
  89. GRB 210704A: CAHA 2.2m Afterglow Detection
  90. GRB 210704A: Swift/UVOT Upper Limits
  91. Konus-Wind detection of GRB 210704A
  92. GRB 210704B: AstroSat CZTI detection
  93. GRB 210619B: ALMA detection
  94. GRB 210704A: TNG detection of the optical afterglow candidate
  95. GRB 210704A: Assy optical afterglow candidate
  96. GRB 210704B: Fermi GBM detection
  97. GRB 210704A: possible local hosts
  98. GRB 210704A: Fermi GBM detection
  99. GRB 210704A: Swift-XRT afterglow detection
  100. GRB 210704A: AstroSat CZTI detection

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