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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"

19663 results found.

  1. LIGO/Virgo/KAGRA S231129ac: Upper limits from Swift/BAT-GUANO
  2. GRB 231203A: Fermi GBM Observation
  3. GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  4. Konus-Wind detection of GRB 231129C
  5. GRB 231129C: Swift-XRT afterglow detection
  6. GRB 231129C: PROMPT optical upper limits for the MAXI/GSC X-ray counterpart and the MASTER afterglow candidate
  7. GRB 231129A: VZLUSAT-2 detection
  8. GRB 231129B: Swift-XRT observations
  9. GRB 231129C: AGILE detection
  10. GRB 231129A : MITSuME Akeno optical upper limits
  11. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  12. GRB 231129A: Swift-BAT refined analysis
  13. GRB 231129C: MASTER OT detection
  14. GRB 231129A: BOOTES-5/JGT optical upper limit
  15. GRB 231129A: JinShan optical upper limit
  16. GRB 231129C: Swift-XRT observations
  17. GRB 231129A: Swift/UVOT Upper Limits
  18. GRB 231129A: optical upper limit in Mondy observatory
  19. GRB 231129C: Tiled Swift observations
  20. GRB 231129A: Enhanced Swift-XRT position
  21. GRB 231129A: Swift-XRT refined Analysis
  22. GRB 231129B: Tiled Swift observations
  23. GRB 231129A: GECAM-C detection of a long burst
  24. GRB 231129A: INTEGRAL detection of a long GRB
  25. GRB 231129A: Swift detection of a burst
  26. GRB 231123C: Fermi GBM Observation
  27. GRB 231123B: Fermi GBM Observation
  28. GRB 231123B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  29. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  30. GRB 231123C: Insight-HXMT/HE detection
  31. GRB 231123C (short): Glowbug gamma-ray detection
  32. GRB230506B: VIRT optical upper limit
  33. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  34. GRB 231115A: XMM-Newton observation
  35. GRB 231118A: REM optical afterglow detection
  36. GRB 231122B: AstroSat CZTI detection
  37. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  38. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  39. GRB 231118A: ATCA detection of radio counterpart
  40. GRB 231117A: Swift/UVOT late time observations
  41. GRB 231117A: Swift-BAT refined analysis
  42. GRB 231118A: GRBAlpha detection
  43. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  44. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  45. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  46. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  47. GRB 231118A: VZLUSAT-2 detection
  48. GRB 231118A: Swift-BAT refined analysis
  49. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  50. 231118A: Swift-UVOT Detection
  51. GRB231117A: Swift-UVOT detection
  52. GRB 231118A: Fermi GBM observation
  53. GRB 231117A: Swift-XRT refined Analysis
  54. GRB 231118A: Swift-XRT refined Analysis
  55. GRB 231118A: MeerLICHT afterglow detection
  56. GRB 231118A: VLT/X-shooter redshift
  57. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  58. GRB 231117A: GECAM-C detection
  59. GRB 231118A: AstroSat CZTI detection
  60. GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
  61. GRB 231118A: Las Cumbres optical detection
  62. GRB 231118A: LCOGT Optical Observations
  63. GRB 231118A: MASTER OT observation
  64. Swift GRB231118.72: Global MASTER-Net observations report
  65. GRB 231118A: Enhanced Swift-XRT position
  66. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  67. GRB 231118A: Swift-XRT position
  68. GRB 231118A: Skynet Optical Afterglow Discovery
  69. GRB 231118A: Swift detection of a burst
  70. GRB 231117A: GRBAlpha detection
  71. GRB 231117A: GIT optical follow-up
  72. GRB 231117A: AKO Optical Upper Limit
  73. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  74. Swift GRB 231117A: Global MASTER-Net observations report
  75. GRB 231117A (short): Glowbug gamma-ray detection
  76. GRB 231117A: ATLAS non-detection of an optical counterpart
  77. Konus-Wind detection of GRB 231117A (short/hard)
  78. GRB 231115A: optical observations from INAF observatories
  79. GRB 231117A : MITSuME Akeno optical upper limits
  80. GRB 231117A: AGILE detection of a bright short burst
  81. GRB 231117A: Enhanced Swift-XRT position
  82. GRB 231117A: GOTO optical upper limits
  83. GRB 231117A: AstroSat CZTI detection of a bright short burst
  84. GRB 231117A: Swift detection of a bright short burst
  85. GRB 231111A: Swift/UVOT Detection
  86. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  87. GRB 231115A: Swift-XRT and Swift-UVOT observations
  88. GRB 231115A: Swift ToO observations
  89. GRB 231111A: Swift-BAT refined analysis
  90. GECAM-B observation of a short burst from SGR J1555-5402
  91. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  92. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  93. GRB 231110A: Swift-BAT refined analysis
  94. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  95. GRB 231111A: Xinglong-2.16m optical observations
  96. GRB 231110A: Swift-UVOT Upper Limits
  97. GRB 231104A: VZLUSAT-2 detection
  98. GRB 231110A: Glowbug gamma-ray detection
  99. GRB 231110A: AstroSat CZTI detection
  100. GRB 231111A: Leavitt Observatory optical observations

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