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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"

28244 results found.

  1. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  2. GRB 231118A: Swift-XRT position
  3. GRB 231118A: Skynet Optical Afterglow Discovery
  4. GRB 231117A: SOAR/Goodman imaging of the afterglow
  5. GRB 231118A: Swift detection of a burst
  6. GRB 231118A: Fermi GBM Final Real-time Localization
  7. GRB 231117A: Lowell Discovery Telescope Observations
  8. GRB 231117A: ePESSTO+ host galaxy redshift confirmation
  9. GRB 231117A: ATCA detection of a radio counterpart
  10. GRB 231117A: GRBAlpha detection
  11. GRB 231117A: Keck spectroscopy of afterglow candidate
  12. GRB 231117A: GIT optical follow-up
  13. GRB 231117A: LT observations consistent with fading
  14. GRB 231117A: Keck observations indicate presence of optical afterglow in z~0.3-0.5 galaxy
  15. GRB 231117A: REM optical and NIR early-time observations
  16. GRB 231117A: AKO Optical Upper Limit
  17. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  18. GRB 231117A (short): Glowbug gamma-ray detection
  19. GRB 231117A: ATLAS non-detection of an optical counterpart
  20. Konus-Wind detection of GRB 231117A (short/hard)
  21. GRB 231117A : MITSuME Akeno optical upper limits
  22. GRB 231117A: AGILE detection of a bright short burst
  23. GRB 231117A: Enhanced Swift-XRT position
  24. GRB 231117A: GOTO optical upper limits
  25. GRB 231117A: AstroSat CZTI detection of a bright short burst
  26. GRB 231117A: Swift detection of a bright short burst
  27. GRB 231115A: Non-detection of radio emission with CHIME/FRB
  28. GRB 231111A: Swift/UVOT Detection
  29. MAGIC observation of GRB 231115A, a possible magnetar giant flare
  30. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  31. GRB 231115A: Swift-XRT and Swift-UVOT observations
  32. Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
  33. GRB 231115A: Insight-HXMT/HE detection
  34. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  35. GRB 231116A: Fermi GBM Final Real-time Localization
  36. GRB 231115A / AT2023xvj: Updated GIT analysis
  37. GRB231115A: GRANDMA Observations
  38. GRB 231115A: Non-detection in low-latency of gravitational waves with LIGO/Virgo/KAGRA
  39. GRB 231106A: TESS identification of candidate optical counterpart
  40. GRB 231115A (short): Glowbug gamma-ray detection
  41. GRB 231115A: Swift ToO observations
  42. GRB 231115A: Fermi GBM Final Real-time Localization
  43. LIGO/Virgo/KAGRA S231113bw: Zwicky Transient Facility observations
  44. GRB 231113A (short): Glowbug gamma-ray detection
  45. GRB 231114A (short): Glowbug gamma-ray detection
  46. GRB 231114A: Fermi GBM Final Localization
  47. LIGO/Virgo/KAGRA S231113bw: Upper limits from Fermi-GBM Observations
  48. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  49. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  50. GRB 231106A: Glowbug gamma-ray detection
  51. GRB 231111A: Xinglong-2.16m optical observations
  52. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  53. GRB 231104A: VZLUSAT-2 detection
  54. GRB 231111A: TNG tentative redshift
  55. GRB 231110A: Glowbug gamma-ray detection
  56. GRB 231110A: AstroSat CZTI detection
  57. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  58. GRB 231111A: Leavitt Observatory optical observations
  59. GRB231111A: Optical follow-up observations with Mephisto
  60. GRB 231111A: GMG observation upper limit
  61. GRB 231106B: GRBAlpha detection
  62. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  63. GRB 231110A: Terskol Zeiss-2000 optical upper limit
  64. GRB 231111A: Swift-XRT refined Analysis
  65. GRB 231111A: Mondy optical observations
  66. GRB 231111A: GECAM-C detection of a long burst (correction)
  67. GRB 231110A: GECAM-B detection (correction)
  68. GRB 231111A: Enhanced Swift-XRT position
  69. GRB 231111A: GECAM-C detection of a long burst
  70. GRB 231110A: GECAM detection
  71. GRB 231110A: GOTO optical upper limits
  72. GRB 231110A: SAO RAS optical observations
  73. GRB 231110A: Swift-XRT afterglow detection
  74. GRB231111A: YAHPT Observations
  75. GRB231111A: GIT confirmation of the optical afterglow
  76. GRB 231111A: MASTER OT earlier detection
  77. GRB 231111A: Nanshan/HMT optical observations
  78. GRB 231111A: Swift detection of a burst with an optical counterpart
  79. GRB231110A: WFST Observation and upper limits
  80. GRB 231110A: Swift detection of a burst
  81. GRB 231109A: Fermi GBM Final Localization
  82. GRB 231108A: Fermi GBM Final Real-time Localization
  83. GRB 231106A: AstroSat CZTI detection
  84. GRB 231106A: CALET Gamma-Ray Burst Monitor detection
  85. GRB 231104A: FRAM-ORM optical limit
  86. GRB 231104A: Wendelstein Optical/Infrared Observations
  87. GRB 231106A: Fermi GBM Final Real-time Localization
  88. GRB 231104A: 3.6m DOT optical upper limit
  89. GRB 231104A: NOT upper limit
  90. GRB 231104B: Fermi GBM Final Real-time Localization
  91. GRB 231104A: AKO Upper Limit
  92. GRB 231104A: AstroSat CZTI detection
  93. GRB 231104A: Swift-XRT refined Analysis
  94. GRB 231104A: Fermi-LAT detection
  95. GRB 231104A: Swift/UVOT Upper Limits
  96. GRB 231104A: Enhanced Swift-XRT position
  97. GRB231104A: LCOGT Optical Upper Limits
  98. GRB 231104A: Swift detection of a bright burst
  99. GRB 231104A: Fermi GBM Final Real-time Localization
  100. GRB 231103A: Fermi GBM Final Real-time Localization

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