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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"

28251 results found.

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

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