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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"

12176 results found.

  1. Konus-Wind detection of GRB 210212B / ZTF21aakruew
  2. GRB 210212B (TF21aakruew/AT2021cwd): Assy optical observations
  3. Swift Trigger 1032350: Detection of SGR 1830-0645
  4. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued CrAO and AbAO optical observations
  5. GRB 210212A: Possible host galaxy counterpart with the NOT
  6. GRB 210212A: Swift-XRT refined Analysis
  7. Fermi-LAT Gamma-ray Observations of IceCube-210210A
  8. Fermi GRB 210210B: Global MASTER-Net observations report
  9. GRB 210210A: Swift/UVOT Detection
  10. GRB 210112A: LBT host detection and correction to GCN 29319 (CAHA observations)
  11. GRB 210210A: Swift-XRT refined Analysis
  12. GRB 210210A: Swift detection of a burst with an optical counterpart
  13. GRB 210207B: AstroSat CZTI detection
  14. GRB 210204A: LBT observations and jet break
  15. GRB 210208A: A long GRB detected by INTEGRAL
  16. GRB 210207B: Swift-XRT refined Analysis
  17. Konus-Wind detection of GRB 210207B
  18. SGR 1935+2154: MAXI/GSC detection
  19. Konus-Wind detection of GRB 210204A (correction to GCN 29415)
  20. Konus-Wind detection of GRB 210204A / ZTF21aagwbjr
  21. GRB 210204A / ZTF21aagwbjr: Swift-XRT observations
  22. GRB 210204A: AstroSat CZTI Detection
  23. GRB 210205A: Swift-BAT refined analysis
  24. IPN triangulation of GRB 210204A
  25. Fermi GRB 210204A: Global MASTER-Net observations report
  26. GRB 210202A: AGILE/MCAL detection
  27. Fermi GBM Observations of a bright burst from SGR J1935+2154
  28. GRB 210202A: Fermi GBM detection
  29. GRB 210202A: Fermi-LAT detection
  30. Recent activity of SGR 1935+2154 as observed by CGBM
  31. GRB 210202A: BALROG localization (Fermi Trigger / GRB 210202841)
  32. INTEGRAL detection of a short burst from SGR 1935+2154
  33. GRB 210202A: Fermi GBM Final Real-time Localization
  34. GECAM observations of SGR 1935+2154
  35. Continued Chandra observations of GW170817 at ~3.3 years since merger
  36. Fermi GBM Observations of SGR J1935+2154
  37. Konus-Wind detection of two bright bursts from SGR 1935+2154
  38. GRB 140330A: Swift-XRT refined Analysis
  39. GRB 140320B: Swift-XRT refined Analysis
  40. GRB 210126A: AstroSat CZTI detection
  41. GRB 210124B: AstroSat CZTI detection
  42. GRB 210123A: AstroSat CZTI detection
  43. IPN triangulation of a bright burst from SGR 1935+2154
  44. GECAM detection of a short burst probably from SGR 1935+2154
  45. GRB 210120A: Fermi GBM detection
  46. Konus-Wind detection of GRB 210121A
  47. Konus-Wind detection of GRB 210124B
  48. IPN triangulation of GRB 210124B (short)
  49. IPN triangulation of GRB 210121A
  50. GRB 210120A : 1.3m DFOT optical observations
  51. GRB 210116A: AstroSat CZTI detection
  52. GRB 210120A(MASTER OT J105242.66+152355.0 / AT2021axc): Mondy optical observations
  53. GRB 210116: AstroSat LAXPC detection
  54. GRB 210120A: MASTER OT (possibly) discovery
  55. GECAM In-Flight Trigger of GRB 210120A
  56. Fermi GRB 210120A: Global MASTER-Net observations report
  57. GRB 210120A: BALROG localization (Fermi Trigger 632819449 / GRB 210120299)
  58. GRB 210120A: Fermi GBM Final Real-time Localization
  59. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  60. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  61. GRB 210119A: Fermi GBM observation
  62. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  63. Fermi GRB 210119A: Global MASTER-Net observations report
  64. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  65. Konus-Wind detection of GRB 210112A
  66. GRB 201221D: near-infrared observation with LBT
  67. GRB 210112A: Mondy optical observations
  68. GRB 210104A: AstroSat CZTI detection
  69. NuEm-210111A: MAXI/GSC upper limit
  70. GRB 210104A: AROMA-N Optical Afterglow Detection
  71. GRB 210110A: MAXI/GSC detection
  72. GRB 210104A: Assy continued optical observations, correction to GCN circ. 29265
  73. GRB 210109A: MAXI/GSC detection
  74. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  75. Correction to GCN 29278: GRB 201216C XRT refined analysis
  76. GRB 201216C: Swift-XRT refined Analysis
  77. GRB 210104A: SAO RAS optical observations
  78. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  79. GRB 210102B: Assy optical afterglow identification
  80. GRB 210104A: Assy continued optical observations
  81. Fermi GRB 210105A: Global MASTER-Net observations report
  82. GRB 210104A: Swift-XRT refined Analysis
  83. Konus-Wind detection of GRB 210104A
  84. GRB 210104B: Assy optical upper limit
  85. GRB 210104A: Swift/UVOT Detection
  86. Swift GRB210104.88: Global MASTER-Net observations report
  87. GRB 210102B: Assy optical observations
  88. Fermi GRB 210104A: Global MASTER-Net observations report
  89. GRB 210104A: Assy optical observations
  90. Fermi GRB 210102C: Global MASTER-Net observations report
  91. GRB 210102C: Fermi GBM detection
  92. GRB 210102C: Swift detection of a burst
  93. GRB 210102B: MAXI/GSC detection
  94. Fermi GRB 210101A: Global MASTER-Net observations report
  95. Swift GRB210102.01: Global MASTER-Net observations report
  96. Fermi trigger No 631226368: Global MASTER-Net observations report
  97. Fermi trigger No 631119348: Global MASTER-Net observations report
  98. Fermi trigger No 631113166: Global MASTER-Net observations report
  99. Fermi trigger No 631118376: Global MASTER-Net observations report
  100. Fermi trigger No 631104264: Global MASTER-Net observations report

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