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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"

36397 results found.

  1. GRB 231222B: GRBAlpha detection
  2. GRB 231222B: Swift-XRT afterglow detection
  3. GRB 231222B: Fermi GBM Detection
  4. GRB 231222B: Fermi-LAT detection
  5. GRB 231222A: Tiled Swift observations
  6. GRID detection of GRB 231215A
  7. GRB 231222A: Fermi GBM Final Real-time Localization
  8. GRB 231220A: Swift-XRT follow-up observations
  9. GRB 231220A: Swift ToO observations
  10. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  11. GRB 231220A: Fermi GBM Final Real-time Localization
  12. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  13. GRB 231219A: Fermi GBM Final Real-time Localization
  14. GRID detection of GRB 231205B
  15. GRID detection of GRB 231205A
  16. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  17. GRB 231214B: Fermi GBM observation
  18. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  19. GRB 231216A: 10.4 m GTC optical upper limit
  20. GRB 231215A: AMI-LA radio detection
  21. GRB 231216A: Nanshan/HMT optical upper limit
  22. GRB 231216A: LCOGT Optical Upper Limits
  23. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  24. GRB 231216A: Swift-XRT refined analysis correction
  25. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  26. GRB 231216A: Swift-XRT refined Analysis
  27. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  28. GRB 231216A: REM NIR upper limits
  29. GRB 231216A: Swift/UVOT Upper Limits
  30. GRB 231216A: Swift-BAT refined analysis
  31. GRB 231215A: Swift-BAT refined analysis
  32. GRB 231214A: Swift-BAT refined analysis
  33. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  34. GRB 231216A: GIT optical upper limit
  35. GRB 231216A: NOT optical upper limits
  36. GRB 231216A: BOOTES-2/TELMA optical upper limit
  37. GRB 231215A: GRBAlpha detection
  38. GRB 231216A: Swift detection of a burst
  39. Konus-Wind detection of GRB 231215A
  40. GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
  41. GRB 231215A: NOT optical observations
  42. GRB 231214A: Swift/UVOT Upper Limits
  43. GRB 231215A: Redshift from OSIRIS+ / GTC
  44. GRB 231205B: VZLUSAT-2 detection
  45. GRB 231204A: VZLUSAT-2 detection
  46. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  47. GRB 231215A: Fermi GBM observation
  48. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  49. GRB 231215A : OHP/T193 optical afterglow detection
  50. GRB 231215A: Swift/UVOT Detection
  51. GRB 231215A: Swift-XRT refined Analysis
  52. GRB 231215A: BOOTES-4/MET optical detection
  53. GRB 231215A: AKO Optical Upper Limit
  54. GRB 231215A: AGILE detection
  55. GRB 231214A: Fermi GBM observation
  56. Konus-Wind detection of GRB 231210B
  57. ATCA observations of GRB 231210B
  58. GRB 231215A: Enhanced Swift-XRT position
  59. GRB 231214A: REM optical/NIR upper limits
  60. GRB 231215A: GROWTH-India optical follow-up
  61. GRB 231215A : Nanshan/HMT optical observations
  62. GRB 231215A: AstroSat CZTI detection
  63. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  64. GRB 231214A: Swift-XRT refined Analysis
  65. GRB 231215A: Mondy optical bright afterglow detection
  66. GRB 231214A: AstroSat CZTI detection
  67. GRB 231215C: MASTER OT detection
  68. GRB 231215A: Swift-XRT observations
  69. GRB 231215B: Fermi GBM Final Real-time Localization
  70. GRB 231215A: Swift detection of a burst
  71. GRB 231214A: Fermi-LAT detection
  72. GRB 231214A: Enhanced Swift-XRT position
  73. GRB 231214B: Swift/BAT-GUANO detection of a burst
  74. GRB231214A: BOOTES-6/DPRT optical upper limit
  75. GRB 231214A: Swift detection of a burst
  76. GRB 231214A: Fermi GBM Final Real-time Localization
  77. GRB 231210B: REM optical/NIR upper limits
  78. IceCube-231211A: Upper limits from a search for additional neutrino events in IceCube
  79. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  80. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  81. GRB 231212A: GECAM-C detection of a likely short burst
  82. GRB 231210B: MeerLICHT afterglow observations
  83. GRB 231210B: Swift-BAT refined analysis
  84. GRB 231210B: Swift-XRT refined Analysis
  85. GRB 231210B: Enhanced Swift-XRT position
  86. GRB 231210B: VLT/X-shooter redshift
  87. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  88. GRB 231210B: Swift detection of a burst with optical counterpart
  89. IPN triangulation of GRB 231129C
  90. GRB 231210A: Fermi GBM Final Real-time Localization
  91. GRB 231208A: GRBAlpha detection
  92. GRB231205B: Swift/UVOT Upper Limits
  93. GRB 231208A: Glowbug gamma-ray detection
  94. GRB 231208A: AstroSat CZTI detection of a faint burst
  95. IPN triangulation of GRB 231205A
  96. GRB 231205B: Swift-BAT refined analysis
  97. GRB 231205B: 1.3m DFOT Optical upper limit
  98. GRB 231206A: joint location of multiple instruments by ETJASMIN
  99. GRB 231205B: optical upper limit in TSHAOand AbAO
  100. GRB231115A: TURBO Pre-Burst Optical Upper Limits

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