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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"

14990 results found.

  1. GRB 210228A: GECAM detection
  2. Integral GRB210227.19: MASTER OT retraction
  3. GRB 210225A: Insight-HXMT/HE detection
  4. Integral GRB210227.19: Global MASTER-Net OT detection
  5. GRB 210226A: Fermi GBM detection
  6. GRB 210218A: Swift-XRT confirmation of afterglow
  7. GRB 210226A: Swift detection of a burst
  8. Konus-Wind detection of GRB 210222A
  9. GRB 210222B: VIRT optical detection
  10. GRB 210222B: Swift/UVOT Detection
  11. GRB 210222B: FRAM-ORM afterglow detection
  12. GRB 210217A: Swift/UVOT Detection
  13. GRB 210222B: MASTER OT observation
  14. GRB 210222A: CALET Gamma-Ray Burst Monitor detection
  15. GRB 210222B: GOTO confirmation of afterglow detection (correction to GCN29548)
  16. GRB 210222B: Liverpool Telescope optical detection
  17. GRB 210222B: GOTO confirmation of afterglow detection
  18. GRB210222B: LCO Optical Afterglow Detection
  19. GRB210222B: BOOTES-1 optical afterglow detection
  20. GRB 210222B: Swift detection of a burst with an optical counterpart
  21. GRB 210222A: MAXI/GSC detection
  22. uGMRT radio detection of GRB 210204A
  23. GRB 210217A: 1.3m DFOT optical detection
  24. Fermi GBM Sub-Threshold Detection of GRB 210217A
  25. GRB 210218A: Swift detection of a burst
  26. GRB 210217A: Swift detection of a burst with an optical counterpart
  27. IceCube-210210A: Two Additional Optical Candidate Counterparts Found by DECam
  28. GRB 210208A: 1.3m DFOT Optical upper limit
  29. GRB 210210A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  30. Swift Trigger 1033144: Detection of SGR 1830-0645
  31. Konus-Wind detection of GRB 210212B / ZTF21aakruew
  32. GRB 210213B: Insight-HXMT/HE detection
  33. ZTF21aakruew/AT2021cwd: ZTF and LT discovery of a hostless, red, and rapidly fading optical transient
  34. IceCube alert 134994_1103075 retraction
  35. GRB 210213A: Fermi GBM Final Real-time Localization
  36. IceCube-210210A: Four Candidate Optical Counterparts from DECam Observations
  37. Swift Trigger 1032350: Detection of SGR 1830-0645
  38. GRB 210212A: BOOTES-4/MET optical upper limit
  39. GRB 210204A: observations with the 3.6m Devasthal Optical Telescope and possible jet break
  40. GRB 210212A: Swift detection of a burst
  41. GRB 210207B: GECAM detection
  42. GRB 210211A: Swift/UVOT Detection
  43. GRB 210210A: CAHA detection and likely jet break
  44. IceCube-210210A: No neutrino counterpart in ANTARES
  45. GRB 210211A: REM optical/NIR afterglow detection
  46. GRB 210211A: Swift detection of a burst
  47. GRB 210211A: Fermi GBM Final Real-time Localization
  48. GRB 210210A: FRAM-ORM afterglow detection
  49. GRB 210210B: Fermi GBM Final Real-time Localization
  50. GRB 210209A: BOOTES-4/MET optical upper limit
  51. GRB 210210A: LCO Optical Afterglow Detection
  52. GRB 210210A: Swift/UVOT Detection
  53. GRB 210112A: LBT host detection and correction to GCN 29319 (CAHA observations)
  54. IceCube-210210A: IceCube observation of a high-energy neutrino candidate event
  55. GRB 210210A: Redshift from OSIRIS/GTC
  56. GRB 210210A: MASTER afterglow observation
  57. ZTF21aahifke/AT2021clk: ZTF discovery of an optical fast transient (possible afterglow)
  58. GRB 210210A: Swift detection of a burst with an optical counterpart
  59. GRB 210209A: Swift detection of a burst
  60. GRB 210207B: Continued LCO Observations
  61. GRB 210208A: BOOTES-2/TELMA optical upper limit
  62. GRB 210207B: AstroSat CZTI detection
  63. GRB 210207B: Swift/UVOT Detection
  64. GRB 210207B: Insight-HXMT/HE detection
  65. GRB 210204A: LBT observations and jet break
  66. GRB 210207B: LCO Optical Afterglow Detection
  67. Konus-Wind detection of GRB 210207B
  68. SGR 1935+2154: MAXI/GSC detection
  69. Konus-Wind detection of GRB 210204A (correction to GCN 29415)
  70. GRB 210207B: AbAO optical upper limit
  71. GRB 210207B: optical detection with 3.6m Devasthal Optical Telescope
  72. GRB 210207B: Swift detection of a burst with a bright optical counterpart
  73. GRB 210207A: Fermi GBM Final Real-time Localization
  74. Konus-Wind detection of GRB 210204A / ZTF21aagwbjr
  75. VLT/X-shooter redshift of 1.466 for ZTF21aagwbjr/AT2021buv, strengthening its association with GRB 210204A
  76. GRB 210204A: AstroSat CZTI Detection
  77. IPN triangulation of GRB 210204A
  78. GRB 210205B: AGILE/MCAL detection of a burst
  79. GRB 210205A: BOOTES-4/MET optical upper limit
  80. GRB 210205A: Swift detection of a burst
  81. GRB 210204B: Fermi GBM Final Real-time Localization
  82. GRB 210204A: GECAM detection
  83. GRB 210204A: Fermi GBM Final Real-time Localization
  84. GRB 210202A: AGILE/MCAL detection
  85. GRB 210202A: Fermi GBM detection
  86. GRB 210202A: Fermi-LAT detection
  87. INTEGRAL detection of a short burst from SGR 1935+2154
  88. GRB 210202A: Fermi GBM Final Real-time Localization
  89. GRB 210131A: GECAM detection
  90. GECAM observations of SGR 1935+2154
  91. GRB 210129A: Insight-HXMT/HE detection
  92. Konus-Wind detection of two bright bursts from SGR 1935+2154
  93. GRB 210126A: AstroSat CZTI detection
  94. GRB 210124B: AstroSat CZTI detection
  95. GRB 210123A: AstroSat CZTI detection
  96. IPN triangulation of a bright burst from SGR 1935+2154
  97. GECAM detection of a short burst probably from SGR 1935+2154
  98. GRB 210127A: Fermi GBM Final Real-time Localization
  99. GRB 210120A: Fermi GBM detection
  100. Konus-Wind detection of GRB 210121A

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