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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"

27965 results found.

  1. GRB 210726A: Swift detection of a burst
  2. Swift GRB210726.80: Global MASTER-Net observations report
  3. GRB 210725B: Swift-XRT refined Analysis
  4. GRB 210725A: Fermi GBM detection
  5. GRB 210725A: Swift-XRT refined Analysis
  6. GRB 210725B: Swift-BAT refined analysis
  7. GRB 210724A: Swift-XRT refined Analysis
  8. GRB 210725A: Swift-BAT refined analysis
  9. GRB 210724A: Swift-BAT refined analysis
  10. Swift GRB 210725B: Global MASTER-Net observations report
  11. GRB 210725B: Enhanced Swift-XRT position
  12. GRB 210725A: MITSuME Akeno optical upper limits
  13. GRB 210725B: Swift detection of a burst
  14. GRB 210725A: CALET Gamma-Ray Burst Monitor detection
  15. GRB 210723A: CALET Gamma-Ray Burst Monitor detection
  16. GRB 210725A: KAIT Optical Upper Limit
  17. GRB 210725A: Swift detection of a burst
  18. Swift GRB210725.16: Global MASTER-Net observations report
  19. GRB 210723A: Fermi GBM Observation
  20. GRB210724A: MeerLICHT upper limits
  21. GRB 210724A: Swift detection of a burst
  22. Swift GRB210724.84: Global MASTER-Net observations report
  23. GRB 210723A: Swift-BAT refined analysis
  24. GRB 210723A: Swift-XRT refined Analysis
  25. GRB 210722A: D50 optical detection
  26. Swift GRB 210723A: Global MASTER-Net observations report
  27. GRB 210722A: Fermi GBM observation
  28. GRB 210722A: Swift-BAT refined analysis
  29. GRB 210722A: Redshift from OSIRIS/GTC
  30. GRB 210723A: Prompt enhanced Swift-XRT position
  31. GRB 210723A: Swift detection of a burst
  32. GRB 210722A: Swift-XRT refined Analysis
  33. GRB 210722A: Swift/UVOT Detection
  34. GRB 210722A: GIT optical detection and preliminary analysis
  35. Swift GRB 210722A: Global MASTER-Net observations report
  36. GRB 210702A: ALMA detection of mm-band rebrightening
  37. GRB 210722A: Assy optical detection
  38. GRB 210702A: ATCA detection of radio rebrightening
  39. GRB 210722A: Nanshan/NEXT optical afterglow observations
  40. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  41. GRB 210719A: GECAM detection
  42. IceCube-210717A: IceCube observation of a high-energy neutrino candidate track-like event
  43. Konus-Wind detection of GRB 210714A
  44. Fermi trigger No 647942198: MASTER optical afterglow detection
  45. GRB 210712A: Swift-BAT refined analysis
  46. GECAM detection of a short burst from SGR J1935+2154
  47. GRB 210712A: Swift-XRT refined Analysis
  48. GRB 210712A: Swift/UVOT Upper Limits
  49. GRB 210712A: BOOTES-3/YA optical upper limit
  50. GRB 210712A: Enhanced Swift-XRT position
  51. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  52. GECAM detection of a short burst from SGR J1935+2154
  53. GRB 210712A: Swift detection of a burst
  54. GRB 210709A: AstroSat CZTI detection
  55. GRB210704A: Gemini near-infrared upper limits
  56. GECAM detection of a short burst from SGR J1935+2154
  57. GRB 210704A: OSIRIS/GTC Observations and Archival Detection of the Possible Host Galaxy
  58. GRB 210704A: Gemini-North Infrared Source Detection
  59. GRB 210706A: Swift/XRT afterglow confirmation
  60. GECAM detection of a short burst from SGR 1935+2154
  61. GRB 210708B: Swift-BAT refined analysis
  62. GRB 210709A: Fermi GBM Final Real-time Localization
  63. Swift GRB 210708B: Global MASTER-Net observations report
  64. GRB 210708A: Swift/UVOT Upper Limits
  65. GRB 210702A: ATCA detection
  66. GRB 210702A: ALMA detection
  67. GRB 210708A: Swift-BAT refined analysis
  68. Fermi GBM Sub-Threshold Detection of GRB 210708A
  69. Fermi GBM Sub-Threshold Detection of GRB 210707A
  70. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  71. GRB 210708B: Swift detection of a possible burst
  72. GRB 210708A: Swift-XRT refined Analysis
  73. GECAM detection of a short burst from SGR 1935+2154
  74. GRB 210708A: Swift detection of a burst
  75. Swift GRB210708.10: Global MASTER-Net observations report
  76. GRB 210704A: CAHA 2.2m telescope optical limit
  77. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  78. Fermi GBM Observations of SGR J1935+2154
  79. Swift-BAT detection of a burst from SGR 1935+2154
  80. GRB 210706A: Fermi GBM observation
  81. GRB 210706A: optical upper limit of Sintesz-Newton/CrAO and AS-32/AbAO
  82. Konus-Wind detection of GRB 210706A
  83. GRB 210706A: GIT optical upper limits
  84. GRB 210704A: OAJ T80 multi-color detections
  85. GECAM detection of a bright short burst from SGR 1935+2154
  86. GRB 210706A: Swift-XRT afterglow detection
  87. GRB 210706A: Swift ToO observations
  88. INTEGRAL detection of a burst from SGR 1935+2154
  89. GRB 210706A: Swift/BAT-GUANO detection and arcminute localization
  90. GRB 210704A: OSIRIS/GTC spectroscopy
  91. GRB 210704A: CAHA 2.2m Afterglow Detection
  92. GRB 210704A: Swift/UVOT Upper Limits
  93. Konus-Wind detection of GRB 210704A
  94. GRB 210704B: AstroSat CZTI detection
  95. GRB 210619B: ALMA detection
  96. GRB 210704A: TNG detection of the optical afterglow candidate
  97. GRB 210704A: Assy optical afterglow candidate
  98. GRB 210704B: Fermi GBM detection
  99. GRB 210704A: possible local hosts
  100. GRB 210704A: Fermi GBM detection

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