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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"

28241 results found.

  1. GRB 231216A: Nanshan/HMT optical upper limit
  2. GRB 231216A: LCOGT Optical Upper Limits
  3. GRB 231216A: Swift-XRT refined analysis correction
  4. GRB 231216A: Swift-XRT refined Analysis
  5. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  6. GRB 231216A: REM NIR upper limits
  7. GRB 231216A: Swift/UVOT Upper Limits
  8. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  9. GRB 231216A: GIT optical upper limit
  10. GRB 231216A: NOT optical upper limits
  11. GRB 231216A: BOOTES-2/TELMA optical upper limit
  12. GRB 231215A: GRBAlpha detection
  13. GRB 231216A: Swift detection of a burst
  14. Konus-Wind detection of GRB 231215A
  15. GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
  16. GRB 231215A: NOT optical observations
  17. GRB 231214A: Swift/UVOT Upper Limits
  18. GRB 231215A: Redshift from OSIRIS+ / GTC
  19. GRB 231205B: VZLUSAT-2 detection
  20. GRB 231204A: VZLUSAT-2 detection
  21. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  22. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  23. GRB 231215A : OHP/T193 optical afterglow detection
  24. GRB 231215A: Swift/UVOT Detection
  25. GRB 231215A: Swift-XRT refined Analysis
  26. GRB 231215A: BOOTES-4/MET optical detection
  27. GRB 231215A: AKO Optical Upper Limit
  28. GRB 231215A: AGILE detection
  29. Konus-Wind detection of GRB 231210B
  30. GRB 231215A: Enhanced Swift-XRT position
  31. GRB 231214A: REM optical/NIR upper limits
  32. GRB 231215A: GROWTH-India optical follow-up
  33. GRB 231215A : Nanshan/HMT optical observations
  34. GRB 231215A: AstroSat CZTI detection
  35. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  36. GRB 231214A: Swift-XRT refined Analysis
  37. GRB 231215A: Mondy optical bright afterglow detection
  38. GRB 231214A: AstroSat CZTI detection
  39. GRB 231215C: MASTER OT detection
  40. GRB 231215A: Swift-XRT observations
  41. GRB 231215B: Fermi GBM Final Real-time Localization
  42. GRB 231215A: Swift detection of a burst
  43. GRB 231214A: Fermi-LAT detection
  44. GRB 231214A: Enhanced Swift-XRT position
  45. GRB 231214B: Swift/BAT-GUANO detection of a burst
  46. GRB231214A: BOOTES-6/DPRT optical upper limit
  47. GRB 231214A: Swift detection of a burst
  48. GRB 231214A: Fermi GBM Final Real-time Localization
  49. GRB 231210B: REM optical/NIR upper limits
  50. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 2047+098, located inside the IceCube-231211A error region
  51. IceCube-231211A - IceCube observation of a high-energy neutrino candidate track-like event
  52. GRB 231212A: GECAM-C detection of a likely short burst
  53. GRB 231210B: MeerLICHT afterglow observations
  54. GRB 231210B: Swift-XRT refined Analysis
  55. GRB 231210B: Enhanced Swift-XRT position
  56. GRB 231210B: VLT/X-shooter redshift
  57. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  58. GRB 231210B: Swift detection of a burst with optical counterpart
  59. Swift GRB231210.90: Global MASTER-Net OT detection
  60. IPN triangulation of GRB 231129C
  61. GRB 231210A: Fermi GBM Final Real-time Localization
  62. GRB 231208A: GRBAlpha detection
  63. GRB231205B: Swift/UVOT Upper Limits
  64. GRB 231208A: Glowbug gamma-ray detection
  65. GRB 231208A: AstroSat CZTI detection of a faint burst
  66. IPN triangulation of GRB 231205A
  67. GRB 231205B: 1.3m DFOT Optical upper limit
  68. GRB 231205B: optical upper limit in TSHAOand AbAO
  69. GRB 231205B: AGILE detection
  70. GRB 231206B: Fermi GBM Final Real-time Localization
  71. GRB 231205B: Ondrejov D50 optical upper limit
  72. GRB 231205B: Swift-XRT refined Analysis
  73. GRB 231205B: REM optical/NIR upper limits
  74. GRB 231129C: ASIM MXGS observation and localization
  75. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  76. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  77. GRB 231206A: GECAM-B detection of a short burst (correction)
  78. GRB 231205B : MITSuME Akeno optical upper limits
  79. GRB 231206A: GECAM-B detection of a short burst
  80. GRB 231205B: Zadko observatory - Gingin optical observations
  81. GRB 231205B: Gaoyazi/GOT optical upper limit
  82. GRB 231205B: Nanshan/HMT optical upper limit
  83. GRB 231205B: GECAM-B detection of a long burst
  84. GRB 231205B: LCOGT Optical Upper Limits
  85. GRB 231205A: DDOTI Upper Limits on the Afterglow
  86. GRB 231205B: Enhanced Swift-XRT position
  87. GRB 231204A: Glowbug gamma-ray detection
  88. GRB 231204A: CALET Gamma-Ray Burst Monitor detection
  89. Fermi-LAT daily aperture light curve of T CrB now available
  90. GRB 231205B: AKO Optical Upper Limit
  91. GRB 231205B: Swift detection of a burst
  92. GRB 231204A: AstroSat CZTI detection
  93. GRB 231205A: GECAM-B detection of a short burst
  94. GRB 231205A: Fermi GBM Final Real-time Localization
  95. GRB 231204A: Fermi GBM Final Real-time Localization
  96. GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  97. Konus-Wind detection of GRB 231129C
  98. IceCube-231202A - IceCube observation of a high-energy neutrino candidate track-like event
  99. The Fermi GBM team reports the detection of a likely SHORT GRB
  100. GRB 231203A: Fermi GBM Final Real-time Localization

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