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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"

26128 results found.

  1. GRB 210212A: Swift/UVOT Upper Limits
  2. GRB 210212A: Swift-BAT refined analysis
  3. GRB 210204A: observations with the 3.6m Devasthal Optical Telescope and possible jet break
  4. GRB 210212A: Enhanced Swift-XRT position
  5. GRB 210210A : 1.3m DFOT optical observations
  6. GRB 210212A: Swift detection of a burst
  7. GRB 210207B: GECAM detection
  8. GRB 210211A: Swift/UVOT Detection
  9. GRB 210211A: Swift-XRT refined Analysis
  10. GRB 210211A: Swift-BAT refined analysis
  11. GRB 210211A: Fermi GBM observation
  12. GRB 210210A as a BdHN II
  13. Swift-XRT observations of IceCube-210210A
  14. GRB 210209A: Swift-BAT refined analysis
  15. GRB 210211A: Enhanced Swift-XRT position
  16. GRB 210211A: MASTER optical observation of REM OT
  17. GRB 210210A: CAHA detection and likely jet break
  18. GRB 210211A: REM optical/NIR afterglow detection
  19. GRB 210211A: Swift detection of a burst
  20. Swift GRB210211.36: Global MASTER-Net observations report
  21. GRB 210210A: FRAM-ORM afterglow detection
  22. GRB 210210A: Swift-BAT refined analysis
  23. GRB 210209A: BOOTES-4/MET optical upper limit
  24. GRB 210210A: LCO Optical Afterglow Detection
  25. Swift GRB 210209A: Global MASTER-Net observations report
  26. GRB 210210A: Swift/UVOT Detection
  27. GRB 210112A: LBT host detection and correction to GCN 29319 (CAHA observations)
  28. GRB 210209A: MITSuME Akeno optical upper limits
  29. GRB 210209A: Swift/UVOT Upper Limits
  30. GRB 210210A: Swift-XRT refined Analysis
  31. GRB 210210A: Redshift from OSIRIS/GTC
  32. GRB 210209A: Swift-XRT refined Analysis
  33. GRB 210210A: Enhanced Swift-XRT position
  34. GRB 210210A: MASTER afterglow observation
  35. ZTF21aahifke/AT2021clk: ZTF discovery of an optical fast transient (possible afterglow)
  36. Swift GRB 210210A: Global MASTER-Net observations report
  37. GRB 210210A: Swift detection of a burst with an optical counterpart
  38. GRB 210209A: Enhanced Swift-XRT position
  39. GRB 210209A: Swift detection of a burst
  40. GRB 210207B: Continued LCO Observations
  41. GRB 210104A: LBT observations
  42. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Mondy optical observations
  43. GRB 210207B: AstroSat CZTI detection
  44. GRB 210207B: Swift/UVOT Detection
  45. GRB 210207B: Swift-BAT refined analysis
  46. GRB 210207B: Insight-HXMT/HE detection
  47. GRB 210204A: LBT observations and jet break
  48. GRB 210204A: redshift revision of ZTF21aagwbjr/AT2021buv (correction to GCN 29411)
  49. GRB 210207B: LCO Optical Afterglow Detection
  50. GRB 210207B: KAIT Optical Observations
  51. GRB 210207B: AGILE observations
  52. GRB 210207B: Swift-XRT refined Analysis
  53. Konus-Wind detection of GRB 210207B
  54. GRB 210207B: AbAO optical upper limit
  55. GRB 210207B: Enhanced Swift-XRT position
  56. GRB 210207B: optical detection with 3.6m Devasthal Optical Telescope
  57. GRB 210207B: Swift detection of a burst with a bright optical counterpart
  58. GRB 210204A (ZTF21aagwbjr/AT2021buv): Mondy and AbAO optical observations
  59. GRB 210204A / ZTF21aagwbjr: Swift-XRT observations
  60. GRB 210204A: Swift ToO observations
  61. GRB 210205A: Swift-BAT refined analysis
  62. IPN triangulation of GRB 210204A
  63. GRB 210205A: Swift-XRT refined Analysis
  64. GRB 210205A: MITSuME Ishigaki optical observation
  65. ZTF21aagwbjr/AT2021buv: ZTF discovery of a fast optical transient likely associated with GRB 210104A
  66. GRB 210205A: Swift/UVOT Upper Limits
  67. Swift GRB 210205A: Global MASTER-Net observations report
  68. GRB 210205A: Nanshan/NEXT optical upper limit
  69. GRB 210205A: BOOTES-4/MET optical upper limit
  70. GRB 210205A: Enhanced Swift-XRT position
  71. GRB 210205A： GWAC-F60A optical upper limit
  72. GRB 210205A: Swift detection of a burst
  73. GRB 210202A: Fermi-LAT detection
  74. Fermi GBM Observations of SGR J1935+2154
  75. GRB 140330A: Swift-XRT refined Analysis
  76. GRB 140320B: Swift-XRT refined Analysis
  77. GRB 140402A: Swift-XRT refined Analysis
  78. GRB 140104B: Swift-XRT refined Analysis
  79. IPN triangulation of a bright burst from SGR 1935+2154
  80. GRB 210120A : 1.3m DFOT optical observations
  81. ZTF21aaeyldq: GROND and CAHA jet break confirmation
  82. GRB 210120A(MASTER OT J105242.66+152355.0 / AT2021axc): Mondy optical observations
  83. GRB 210112A: 3.6m DOT optical detection
  84. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  85. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  86. GRB 210119A: Insight-HXMT/HE detection
  87. GRB 210119A: Fermi GBM observation
  88. GRB 210112A: Insight-HXMT/HE detection
  89. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  90. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  91. ZTF21aaeyldq CAHA 2.2m detection and power-law decay
  92. GRB 210112A: Deep CAHA 2.2m detection
  93. GRB 210104A: Late-time CAHA 2.2m detection
  94. Konus-Wind detection of GRB 210112A
  95. ZTF21aaeyldq (AT2021any): Detection of X-ray Emission with Swift/XRT
  96. GRB 201221D: near-infrared observation with LBT
  97. ZTF21aaeyldq: NOT optical observations
  98. ZTF21aaeyldq: observations with the 3.6m Devasthal Optical Telescope
  99. ZTF21aaeyldq: GTC Redshift and GRB afterglow nature confirmation
  100. GRB 210104A: JCMT SCUBA-2 sub-mm observations

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