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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"

21525 results found.

  1. GRB 210211A: Swift/UVOT Detection
  2. GRB 210211A: Swift-XRT refined Analysis
  3. GRB 210211A: Swift-BAT refined analysis
  4. GRB 210211A: Fermi GBM observation
  5. Swift-XRT observations of IceCube-210210A
  6. GRB 210209A: Swift-BAT refined analysis
  7. GRB 210211A: Enhanced Swift-XRT position
  8. GRB 210211A: MASTER optical observation of REM OT
  9. GRB 210211A: REM optical/NIR afterglow detection
  10. GRB 210211A: Swift detection of a burst
  11. Swift GRB210211.36: Global MASTER-Net observations report
  12. GRB 210210A: Swift-BAT refined analysis
  13. GRB 210209A: BOOTES-4/MET optical upper limit
  14. GRB 210210A: LCO Optical Afterglow Detection
  15. Swift GRB 210209A: Global MASTER-Net observations report
  16. GRB 210210A: Swift/UVOT Detection
  17. GRB 210209A: MITSuME Akeno optical upper limits
  18. GRB 210209A: Swift/UVOT Upper Limits
  19. GRB 210210A: Swift-XRT refined Analysis
  20. GRB 210210A: Redshift from OSIRIS/GTC
  21. GRB 210209A: Swift-XRT refined Analysis
  22. GRB 210210A: Enhanced Swift-XRT position
  23. GRB 210210A: MASTER afterglow observation
  24. Swift GRB 210210A: Global MASTER-Net observations report
  25. GRB 210210A: Swift detection of a burst with an optical counterpart
  26. GRB 210209A: Enhanced Swift-XRT position
  27. GRB 210209A: Swift detection of a burst
  28. GRB 210207B: Continued LCO Observations
  29. GRB 210207B: AstroSat CZTI detection
  30. GRB 210207B: Swift/UVOT Detection
  31. GRB 210207B: Swift-BAT refined analysis
  32. GRB 210207B: Insight-HXMT/HE detection
  33. GRB 210207B: LCO Optical Afterglow Detection
  34. GRB 210207B: KAIT Optical Observations
  35. GRB 210207B: AGILE observations
  36. GRB 210207B: Swift-XRT refined Analysis
  37. Konus-Wind detection of GRB 210207B
  38. GRB 210207B: Enhanced Swift-XRT position
  39. GRB 210207B: optical detection with 3.6m Devasthal Optical Telescope
  40. GRB 210207B: Swift detection of a burst with a bright optical counterpart
  41. GRB 210204A / ZTF21aagwbjr: Swift-XRT observations
  42. GRB 210204A: Swift ToO observations
  43. GRB 210205A: Swift-BAT refined analysis
  44. IPN triangulation of GRB 210204A
  45. GRB 210205A: Swift-XRT refined Analysis
  46. GRB 210205A: MITSuME Ishigaki optical observation
  47. GRB 210205A: Swift/UVOT Upper Limits
  48. Swift GRB 210205A: Global MASTER-Net observations report
  49. GRB 210205A: Nanshan/NEXT optical upper limit
  50. GRB 210205A: BOOTES-4/MET optical upper limit
  51. GRB 210205A: Enhanced Swift-XRT position
  52. GRB 210205A： GWAC-F60A optical upper limit
  53. GRB 210205A: Swift detection of a burst
  54. GRB 210202A: Fermi-LAT detection
  55. Fermi GBM Observations of SGR J1935+2154
  56. GRB 140330A: Swift-XRT refined Analysis
  57. GRB 140320B: Swift-XRT refined Analysis
  58. GRB 140402A: Swift-XRT refined Analysis
  59. GRB 140104B: Swift-XRT refined Analysis
  60. IPN triangulation of a bright burst from SGR 1935+2154
  61. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  62. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  63. GRB 210119A: Insight-HXMT/HE detection
  64. GRB 210119A: Fermi GBM observation
  65. GRB 210112A: Insight-HXMT/HE detection
  66. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  67. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  68. GRB 210112A: Deep CAHA 2.2m detection
  69. GRB 210104A: Late-time CAHA 2.2m detection
  70. Konus-Wind detection of GRB 210112A
  71. ZTF21aaeyldq (AT2021any): Detection of X-ray Emission with Swift/XRT
  72. GRB 210104A: JCMT SCUBA-2 sub-mm observations
  73. GRB 210112A: Swift/UVOT Detection
  74. GRB 210112A: 1.3m DFOT Optical upper limit
  75. GRB 210104A: AstroSat CZTI detection
  76. GRB 210112A: Swift-BAT refined analysis
  77. GRB 210112A: OSN Reddened Afterglow Detection
  78. GRB 210112A: Swift-XRT refined Analysis
  79. GRB 210112A: AGILE detection
  80. GRB 210112A: Kitab a optical upper limit
  81. GRB 210112A: Enhanced Swift-XRT position
  82. GRB 210112A: Swift detection of a burst with an optical counterpart
  83. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  84. Correction to GCN 29278: GRB 201216C XRT refined analysis
  85. GRB 201216C: Swift-XRT refined Analysis
  86. GRB 201227A: ASIM observation
  87. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  88. GRB 210102B: further Swift-XRT observations
  89. GRB 210102B: Assy optical afterglow identification
  90. GRB 210104A: CALET Gamma-Ray Burst Monitor detection
  91. GRB 210104B: Swift-BAT refined analysis
  92. GRB 210104A: early ATLAS detections of the bright afterglow
  93. GRB 210104A: Swift-XRT refined Analysis
  94. GRB 210104B: Swift/UVOT Upper Limits
  95. Konus-Wind detection of GRB 210104A
  96. GRB 210104A: 1.3m DFOT Optical Afterglow Detection
  97. GRB 210104B: Swift-XRT refined Analysis
  98. GRB 210104B: Assy optical upper limit
  99. GRB 210104B: Enhanced Swift-XRT position
  100. GRB 210104A: Swift-BAT refined analysis

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