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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"

27309 results found.

  1. GRB 230405B: Swift detection of a burst
  2. GRB 230405B: Fermi GBM Final Real-time Localization
  3. Fermi GRB 230405A: Global MASTER-Net observations report
  4. GRB 230405A: Fermi GBM Final Real-time Localization
  5. GRB 230404A: Fermi GBM Final Real-time Localization
  6. GRB 230402A: CALET Gamma-Ray Burst Monitor detection
  7. GRB 230307A: Chandra late-time detection of the X-ray afterglow
  8. GRB 230328B: Swift/UVOT Detection
  9. Fermi GRB 230402A: Global MASTER-Net observations report
  10. GRB 230402A: Fermi GBM Final Real-time Localization
  11. GRB 230307A: Bad Time Intervals for Fermi GBM data
  12. GRB 230328B : GRANDMA/Kilonova-Catcher optical detection
  13. GRB 230328B: 3.6m DOT multiband optical observation
  14. Fermi trigger No 701883729: Global MASTER-Net observations report
  15. GRB 230330B: Fermi GBM Final Localization
  16. GRB 230328B: GRBAlpha detection
  17. GRB 230330A: Fermi GBM Final Real-time Localization
  18. GRB 230328B: Swift-BAT refined analysis
  19. GRB 230328B: Nanshan/NEXT 2nd optical observation
  20. GRB 230328B NUTTelA-TAO / BSTI Early Measurements
  21. GRB 230328B: OHP/T120 optical observations
  22. GRB 230328B: GIT optical follow-up
  23. GRB 230328B: Nanshan/NEXT optical upper limit
  24. GRB 230328B: Swift-XRT refined Analysis
  25. GRB 230328B: Fermi GBM observation
  26. GRB 230328B: Swift detection of a burst with an optical afterglow
  27. GRB 230328B: Fermi GBM Final Real-time Localization
  28. Fermi GRB 230328A: Global MASTER-Net observations report
  29. GRB 230328A: Fermi GBM Final Real-time Localization
  30. GRB 230325A: Swift-BAT refined analysis
  31. GRB 230325A: Swift/UVOT Upper Limits
  32. GRB 230325A: Swift-XRT refined Analysis
  33. GRB 230322B: Swift-BAT refined analysis
  34. GRB 230325A: Swift detection of a burst
  35. GRB 230320B: Fermi GBM Observation
  36. Fermi trigger No 701313046: Global MASTER-Net observations report
  37. Fermi trigger No 701321709: Global MASTER-Net observations report
  38. GRB 230322B: Swift/UVOT Detection
  39. GRB 230322B: Swift-XRT refined Analysis
  40. Swift GRB 230322B: Global MASTER-Net observations report
  41. GRB 230322B: Swift detection of a burst with optical counterpart
  42. GRB 230322A: Fermi GBM Final Real-time Localization
  43. GRB 230320B: GRBAlpha detection
  44. GRB 230321A: CALET Gamma-Ray Burst Monitor detection
  45. GRB 230320B: CALET Gamma-Ray Burst Monitor detection
  46. Fermi trigger No 701071944: Global MASTER-Net observations report
  47. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  48. Fermi GRB 230320A: Global MASTER-Net observations report
  49. Fermi GRB 230321A: Global MASTER-Net observations report
  50. Fermi trigger No 701058254: Global MASTER-Net observations report
  51. SGR 1806-20: Correction to GCN 33494
  52. INTEGRAL detection of a burst from SGR 1806-200
  53. GRB 230321A: BALROG localization (Fermi Trigger 701065308 / GRB 230321182)
  54. GRB 230321A: Fermi GBM Final Real-time Localization
  55. GRB 230320A: Fermi GBM Final Real-time Localization
  56. GRB 230314A: TURBO Optical Upper Limit
  57. Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
  58. Fermi trigger No 700976129: Global MASTER-Net observations report
  59. Fermi GRB 230316A: Global MASTER-Net observations report
  60. GRB 230304D: AstroSat CZTI detection
  61. GRB 230316A: Fermi GBM Final Real-time Localization
  62. IPN triangulation of GRB 230304B
  63. IPN triangulation of GRB 230308A (short/bright)
  64. Fermi GRB 230314A: Global MASTER-Net observations report
  65. GRB 230314A: Fermi GBM Final Real-time Localization
  66. GRB 230307A: Swift/UVOT detection
  67. GRB 230313A: BALROG localization (Fermi Trigger 700400328 / GRB 230313485)
  68. Fermi GRB 230313A: Global MASTER-Net observations report
  69. GRB 230313A: Fermi GBM Final Real-time Localization
  70. GRB 230307A: soft X-ray detection with LEIA
  71. Swift GRB230311.85: Global MASTER-Net observations report
  72. Swift GRB230311.83: Global MASTER-Net observations report
  73. Swift GRB230311.81: Global MASTER-Net observations report
  74. Swift GRB230311.84: Global MASTER-Net observations report
  75. Swift Trigger 1159438 is also due to the Star Tracker loss of lock.
  76. Swift GRB230311.82: Global MASTER-Net observations report
  77. Triggers 1159434, 1159435 and 1159437: Swift detection of Sco X-1 due to Star Tracker loss of lock
  78. Alert from the HAWC Burst Monitor HAWC-230311A
  79. TESS Detection of the Optical Afterglow of GRB230307A
  80. GRB 230308A: CALET Gamma-Ray Burst Monitor detection
  81. Trigger 1159327: Swift detection of SGR1806-20
  82. GRB 230307A: MAXI/GSC upper limit
  83. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  84. Fermi GRB 230310A: Global MASTER-Net observations report
  85. GRB 230310A: Fermi GBM Final Real-time Localization
  86. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  87. GRB 230204B: MASTER detection of an object near NTT Optical Afterglow Candidate
  88. GRB 230308A: Fermi GBM detection
  89. GRB 230307A: ASO-S/HXI detection
  90. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  91. Swift Trigger 1159108 is not a GRB
  92. GRB 230307A: Upper limits from a neutrino search with IceCube
  93. Fermi GRB 230307A: Global MASTER-Net observations report
  94. GRB 230304B: CALET Gamma-Ray Burst Monitor detection
  95. Fermi GRB 230308A: Global MASTER-Net observations report
  96. GRB 230308A: BALROG localization (Fermi Trigger 699975152 / GRB 230308564)
  97. GRB 230308A: Fermi GBM Final Real-time Localization
  98. GRB 230305A: Detection by GRBAlpha
  99. GRB 230307A: BALROG localization (Fermi Trigger 699896651/ GRB 230307656)
  100. IPN triangulation of GRB 230307A (long/very bright)

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