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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"

20008 results found.

  1. GRB 230414B: 1.3m DFOT Optical observations
  2. GRB 230414B: GROWTH India Telescope afterglow confirmation
  3. GRB 230414B: Nanshan/HMT optical afterglow detection
  4. GRB 230414A: Mondy optical afterglow candidate
  5. Swift GRB 230414B: Global MASTER-Net observations report
  6. GRB 230414B: Prompt enhanced Swift-XRT position
  7. GRB 230414B: Swift detection of a burst
  8. GRB 230328B: redshift lower limit estimating
  9. GRB 230409B: Mondy optical upper limit
  10. GRB 230409B: Swift-XRT refined Analysis
  11. GRB 230409B: Swift-BAT refined analysis
  12. Swift GRB 230409B: Global MASTER-Net observations report
  13. GRB 230409B: Swift/UVOT Detection
  14. GRB 230409B: Enhanced Swift-XRT position
  15. GRB 230409B: Swift detection of a burst
  16. GRB 230405B: VZLUSAT-2 detection
  17. Konus-Wind detection of GRB 230405B
  18. GRB 230405B: AGILE detection
  19. GRB 230405B: Swift-XRT refined Analysis
  20. GRB 230405B: Fermi GBM Observation
  21. GRB 230405B: MeerLICHT upper limits
  22. GRB 230405B: Swift/UVOT Upper Limits
  23. GRB 230405B: AstroSat CZTI detection
  24. GRB 230405B: Enhanced Swift-XRT position
  25. Swift GRB 230405B: Global MASTER-Net observations report
  26. GRB 230405B: Prompt enhanced Swift-XRT position
  27. GRB 230405B: Swift detection of a burst
  28. GRB 230307A: Chandra late-time detection of the X-ray afterglow
  29. GRB 230228A: detection by GTC of the potential host galaxy
  30. GRB 230328B: Swift/UVOT Detection
  31. GRB 230328B : GRANDMA/Kilonova-Catcher optical detection
  32. GRB 230328B: CAHA 2.2m/CAFOS detection
  33. GRB 230328B: 3.6m DOT multiband optical observation
  34. Konus-Wind detection of GRB 230328B
  35. GRB 230328B: GRBAlpha detection
  36. GRB 230328B: Swift-BAT refined analysis
  37. GRB 230328B: Nanshan/NEXT 2nd optical observation
  38. GRB 230328B: Liverpool Telescope afterglow detection
  39. GRB 230328B: GIT optical follow-up
  40. GRB 230328B: OASDG optical observations
  41. GRB 230328B: Nanshan/NEXT optical upper limit
  42. GRB 230328B: Swift-XRT refined Analysis
  43. GRB 230328B: AstroSat CZTI detection
  44. GRB 230328B: Fermi GBM observation
  45. GRB 230328B: Mondy, AbAO and Kitab optical observations
  46. GRB 230328B: Enhanced Swift-XRT position
  47. GRB 230328B: Mondy optical afterglow confirmation
  48. GRB 230328B: Swift detection of a burst with an optical afterglow
  49. GRB 230325A: Swift-BAT refined analysis
  50. GRB 230325A: Swift/UVOT Upper Limits
  51. GRB 230325A: Swift-XRT refined Analysis
  52. GRB 230322B: Swift-BAT refined analysis
  53. GRB 230325A: Enhanced Swift-XRT position
  54. GRB 230325A: Prompt enhanced Swift-XRT position
  55. GRB 230325A: Swift detection of a burst
  56. GRB 230320B: Fermi GBM Observation
  57. GRB 230322B: Swift/UVOT Detection
  58. GRB 230322B: Swift-XRT refined Analysis
  59. GRB 230322B: Enhanced Swift-XRT position
  60. Swift GRB 230322B: Global MASTER-Net observations report
  61. GRB 230322B: Swift detection of a burst with optical counterpart
  62. GRB 230320B: GRBAlpha detection
  63. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  64. SGR 1806-20: Correction to GCN 33494
  65. INTEGRAL detection of a burst from SGR 1806-200
  66. Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
  67. IPN triangulation of GRB 230309A
  68. VZLUSAT-2 detection of SGR 1806-20
  69. GRB 230307A: Swift/UVOT detection
  70. GRB 230307A: soft X-ray detection with LEIA
  71. GRB 230307A: Swift-XRT afterglow detection
  72. Swift GRB230311.85: Global MASTER-Net observations report
  73. Swift GRB230311.83: Global MASTER-Net observations report
  74. Further improved IPN localization for GRB 230307A
  75. Swift GRB230311.81: Global MASTER-Net observations report
  76. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  77. Swift GRB230311.84: Global MASTER-Net observations report
  78. Swift Trigger 1159438 is also due to the Star Tracker loss of lock.
  79. Swift GRB230311.82: Global MASTER-Net observations report
  80. Triggers 1159434, 1159435 and 1159437: Swift detection of Sco X-1 due to Star Tracker loss of lock
  81. Trigger 1159327: Swift detection of SGR1806-20
  82. GRB 230307A: MAXI/GSC upper limit
  83. GRB 230307A: Possible optical afterglow
  84. GRB 230307A: ASO-S/HXI detection
  85. GRB 230307A: optical upper limit
  86. GRB 230217A: ATCA rapid-response radio detection
  87. Swift Trigger 1159108 is not a GRB
  88. GRB 230307A: Swift/BAT upper limits on the early afterglow
  89. GRB 230307A: Swift-XRT observations
  90. Improved IPN localization for GRB 230307A
  91. GRB 230307A: Tiled Swift observations
  92. IPN triangulation of GRB 230307A (long/very bright)
  93. GRB 230228A: Swift-BAT refined analysis
  94. GRB 230228A: Swift/UVOT Upper Limits
  95. GRB 230228A: Fermi GBM Observation
  96. GRB 230228A: OSN optical upper limit
  97. GRB 230228A: Swift-XRT refined Analysis
  98. GRB 230228A: Mondy optical upper limit
  99. GRB 230228A: Enhanced Swift-XRT position
  100. GRB 230228A: Nanshan/NEXT optical upper limit

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