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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"

27297 results found.

  1. GRB 231212A: GECAM-C detection of a likely short burst
  2. Fermi trigger No 724035412: Global MASTER-Net observations report
  3. GRB 231210B: MeerLICHT afterglow observations
  4. GRB 231210B: Swift-BAT refined analysis
  5. IceCube Alert 231211.03: Global MASTER-Net observations report
  6. GRB 231210B: Swift-XRT refined Analysis
  7. GRB 231210B: VLT/X-shooter redshift
  8. Fermi trigger No 723906955: Global MASTER-Net observations report
  9. GRB 231210B: Swift detection of a burst with optical counterpart
  10. Swift GRB231210.90: Global MASTER-Net OT detection
  11. Swift GRB231210.90: Global MASTER-Net observations report
  12. GRB 231210A: Fermi GBM Final Real-time Localization
  13. GRB 231208A: GRBAlpha detection
  14. GRB231205B: Swift/UVOT Upper Limits
  15. IPN triangulation of GRB 231205A
  16. GRB 231205B: Swift-BAT refined analysis
  17. GRB 231205B: 1.3m DFOT Optical upper limit
  18. GRB231115A: TURBO Pre-Burst Optical Upper Limits
  19. Fermi trigger No 723581802: Global MASTER-Net observations report
  20. GRB 231206B: Fermi GBM Final Real-time Localization
  21. GRB 231205B: Ondrejov D50 optical upper limit
  22. GRB 231205B: Swift-XRT refined Analysis
  23. GRB 231205B: REM optical/NIR upper limits
  24. GRB 231129C: ASIM MXGS observation and localization
  25. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  26. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  27. GRB 231205B : MITSuME Akeno optical upper limits
  28. GRB 231206A: GECAM-B detection of a short burst
  29. GRB 231205B: Zadko observatory - Gingin optical observations
  30. GRB 231205B: Gaoyazi/GOT optical upper limit
  31. GRB 231205B: Nanshan/HMT optical upper limit
  32. GRB 231205B: GECAM-B detection of a long burst
  33. GRB 231205B: LCOGT Optical Upper Limits
  34. GRB 231205A: DDOTI Upper Limits on the Afterglow
  35. LIGO/Virgo/KAGRA S231205c: One counterpart neutrino candidate event from an IceCube neutrino search
  36. Swift GRB231205.70: Global MASTER-Net observations report
  37. GRB 231204A: CALET Gamma-Ray Burst Monitor detection
  38. GRB 231205B: AKO Optical Upper Limit
  39. GRB 231205B: Swift detection of a burst
  40. GRB 231205A: GECAM-B detection of a short burst
  41. Fermi trigger No 723435916: Global MASTER-Net observations report
  42. Fermi trigger No 723326169: Global MASTER-Net observations report
  43. GRB 231205A: Fermi GBM Final Real-time Localization
  44. LIGO/Virgo/KAGRA S231129ac: Upper limits from Swift/BAT-GUANO
  45. Fermi trigger No 723412808: Global MASTER-Net observations report
  46. GRB 231203A: Fermi GBM Observation
  47. GRB 231204A: Fermi GBM Final Real-time Localization
  48. GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  49. Fermi trigger No 723279695: Global MASTER-Net observations report
  50. The Fermi GBM team reports the detection of a likely SHORT GRB
  51. GRB 231203A: Fermi GBM Final Real-time Localization
  52. Fermi trigger No 723149952: Global MASTER-Net observations report
  53. GRB 231129A : MITSuME Akeno optical upper limits
  54. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  55. GRB 231129A: Swift-BAT refined analysis
  56. GRB 231129C: MASTER OT detection
  57. GRB 231129A: BOOTES-5/JGT optical upper limit
  58. GRB 231129C: Fermi-LAT detection
  59. GRB 231129A: JinShan optical upper limit
  60. GRB 231129A: Swift/UVOT Upper Limits
  61. GRB 231129C: GECAM-B detection of a bright burst
  62. GRB 231129C: CALET Gamma-Ray Burst Monitor detection
  63. GRB 231129C: Fermi GBM Observation of a very bright GRB
  64. GRB 231127A: GRBAlpha detection
  65. GRB 231129C: BALROG localization (Fermi Trigger / GRB 231129799)
  66. GRB 231129C: Fermi GBM detection of a very bright burst
  67. GRB 231129A: Swift-XRT refined Analysis
  68. GRB 231129C: Fermi GBM Final Real-time Localization
  69. Fermi trigger No 722977823: Global MASTER-Net observations report
  70. Integral GRB231129.21: Global MASTER-Net observations report
  71. GRB 231129A: GECAM-C detection of a long burst
  72. GRB 231129A: Swift detection of a burst
  73. GRB 231128A: Fermi GBM Final Real-time Localization
  74. GRB 231123C: Fermi GBM Observation
  75. GRB 231123B: Fermi GBM Observation
  76. GRB 231127A: CALET Gamma-Ray Burst Monitor detection
  77. GRB 231125A: CALET Gamma-Ray Burst Monitor detection
  78. GRB 231127A: AstroSat CZTI detection
  79. GRB 231123B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  80. Fermi trigger No 722653947: Global MASTER-Net observations report
  81. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  82. GRB 231126A: Fermi GBM Final Real-time Localization
  83. GRB 231123C: Insight-HXMT/HE detection
  84. Fermi trigger No 722460326: Global MASTER-Net observations report
  85. Fermi trigger No 722507896: Global MASTER-Net observations report
  86. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  87. Fermi trigger No 722462310: Global MASTER-Net observations report
  88. GRB 231124A: CALET Gamma-Ray Burst Monitor detection
  89. GRB 231115A: XMM-Newton observation
  90. GRB 231124A: Fermi GBM Final Real-time Localization
  91. GRB 231123C: Fermi GBM Final Real-time Localization
  92. GRB 231123B: Fermi GBM Final Real-time Localization
  93. Fermi trigger No 722400249: Global MASTER-Net observations report
  94. GRB 231118A: REM optical afterglow detection
  95. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  96. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  97. GRB 231123A: Fermi GBM Final Real-time Localization
  98. GRB 231122B: Glowbug gamma-ray detection
  99. GRB 231117A: Continued GTC Observations
  100. Fermi trigger No 722349867: Global MASTER-Net observations report

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