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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

11856 results found.

  1. GRB 210312B: MASTER OT confirmation
  2. GRB 210312B: A long GRB detected by INTEGRAL
  3. Integral GRB210312.87: Global MASTER-Net observations report
  4. INTEGRAL SPI-ACS on 2021-03-12 (04)11-08:15) are due to calibration activity
  5. Konus-Wind detection of GRB 210308A
  6. Konus-Wind detection of GRB 210306A
  7. Konus-Wind detection of GRB 210305A
  8. GRB 210306A: Swift/UVOT Detection
  9. GRB 210306A: Swift-XRT refined Analysis
  10. Swift GRB210307.36: Global MASTER-Net observations report
  11. GRB 210306A: iTelescope T24 optical observations
  12. GRB 210306A: Fermi-LAT detection
  13. GRB 210217A: 3.6m DOT optical observations
  14. Fermi trigger No 636168178: Global MASTER-Net observations report
  15. Integral GRB210227.19: Global MASTER-Net observations report
  16. GRB 210226A: Swift-XRT refined Analysis
  17. Swift GRB 210226A: Global MASTER-Net observations report
  18. GRB 210226A: Swift detection of a burst
  19. GRB 210222B: REM observations of the optical/NIR afterglow
  20. Konus-Wind detection of GRB 210222A
  21. GRB 210222B: Zeiss-1000 of Koshka observatory, optical observations
  22. GRB 210222B: Swift-BAT refined analysis
  23. GRB 210222B: Swift-XRT refined Analysis
  24. GRB 210222B: Swift/UVOT Detection
  25. GRB 210222B: FRAM-ORM afterglow detection
  26. GRB 210222B: Swift detection of a burst with an optical counterpart
  27. GRB 210222A: MAXI/GSC detection
  28. uGMRT radio detection of GRB 210204A
  29. GRB 210217A: Swift-XRT refined Analysis
  30. GRB 210218A: Swift detection of a burst
  31. GRB 210217A: Swift detection of a burst with an optical counterpart
  32. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Assy and Mondy optical observations
  33. GRB 210210A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  34. Konus-Wind detection of GRB 210212B / ZTF21aakruew
  35. GRB 210212B (TF21aakruew/AT2021cwd): Assy optical observations
  36. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued CrAO and AbAO optical observations
  37. GRB 210212A: Possible host galaxy counterpart with the NOT
  38. GRB 210212A: Swift-XRT refined Analysis
  39. Fermi-LAT Gamma-ray Observations of IceCube-210210A
  40. Fermi GRB 210210B: Global MASTER-Net observations report
  41. GRB 210210A: Swift/UVOT Detection
  42. GRB 210112A: LBT host detection and correction to GCN 29319 (CAHA observations)
  43. GRB 210210A: Swift-XRT refined Analysis
  44. GRB 210210A: Swift detection of a burst with an optical counterpart
  45. GRB 210207B: AstroSat CZTI detection
  46. GRB 210204A: LBT observations and jet break
  47. GRB 210208A: A long GRB detected by INTEGRAL
  48. GRB 210207B: Swift-XRT refined Analysis
  49. Konus-Wind detection of GRB 210207B
  50. SGR 1935+2154: MAXI/GSC detection
  51. Konus-Wind detection of GRB 210204A (correction to GCN 29415)
  52. Konus-Wind detection of GRB 210204A / ZTF21aagwbjr
  53. GRB 210204A / ZTF21aagwbjr: Swift-XRT observations
  54. GRB 210204A: AstroSat CZTI Detection
  55. GRB 210205A: Swift-BAT refined analysis
  56. IPN triangulation of GRB 210204A
  57. Fermi GRB 210204A: Global MASTER-Net observations report
  58. GRB 210202A: AGILE/MCAL detection
  59. GRB 210202A: Fermi GBM detection
  60. GRB 210202A: Fermi-LAT detection
  61. GRB 210202A: BALROG localization (Fermi Trigger / GRB 210202841)
  62. GRB 210202A: Fermi GBM Final Real-time Localization
  63. Continued Chandra observations of GW170817 at ~3.3 years since merger
  64. Fermi GBM Observations of SGR J1935+2154
  65. Konus-Wind detection of two bright bursts from SGR 1935+2154
  66. GRB 140330A: Swift-XRT refined Analysis
  67. GRB 140320B: Swift-XRT refined Analysis
  68. GRB 210126A: AstroSat CZTI detection
  69. GRB 210124B: AstroSat CZTI detection
  70. GRB 210123A: AstroSat CZTI detection
  71. GRB 210120A: Fermi GBM detection
  72. Konus-Wind detection of GRB 210121A
  73. Konus-Wind detection of GRB 210124B
  74. IPN triangulation of GRB 210121A
  75. GRB 210120A : 1.3m DFOT optical observations
  76. GRB 210116A: AstroSat CZTI detection
  77. GRB 210120A(MASTER OT J105242.66+152355.0 / AT2021axc): Mondy optical observations
  78. GRB 210116: AstroSat LAXPC detection
  79. GRB 210120A: MASTER OT (possibly) discovery
  80. GECAM In-Flight Trigger of GRB 210120A
  81. Fermi GRB 210120A: Global MASTER-Net observations report
  82. GRB 210120A: BALROG localization (Fermi Trigger 632819449 / GRB 210120299)
  83. GRB 210120A: Fermi GBM Final Real-time Localization
  84. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  85. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  86. Fermi GRB 210119A: Global MASTER-Net observations report
  87. Konus-Wind detection of GRB 210112A
  88. GRB 201221D: near-infrared observation with LBT
  89. GRB 210112A: Mondy optical observations
  90. GRB 210104A: AstroSat CZTI detection
  91. NuEm-210111A: MAXI/GSC upper limit
  92. GRB 210104A: AROMA-N Optical Afterglow Detection
  93. GRB 210110A: MAXI/GSC detection
  94. GRB 210104A: Assy continued optical observations, correction to GCN circ. 29265
  95. GRB 210109A: MAXI/GSC detection
  96. Correction to GCN 29278: GRB 201216C XRT refined analysis
  97. GRB 201216C: Swift-XRT refined Analysis
  98. GRB 210104A: SAO RAS optical observations
  99. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  100. GRB 210102B: Assy optical afterglow identification

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