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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').
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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"

36400 results found.

  1. GRB 231118A: REM optical afterglow detection
  2. GRB 231122B: AstroSat CZTI detection
  3. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  4. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  5. GRB 231117A: Chandra afterglow detection
  6. GRB 231123A: Fermi GBM Final Real-time Localization
  7. GRB 231122B: Glowbug gamma-ray detection
  8. GRB 231117A: Continued GTC Observations
  9. GRB 231122A: GECAM detection
  10. GRB 231122B: GECAM detection
  11. GRB 231122A: Fermi GBM Final Real-time Localization
  12. GRB 231118A: ATCA detection of radio counterpart
  13. GRB 231117A: Swift/UVOT late time observations
  14. GRB 231117A: GTC Near-Infrared Observations
  15. GRB 231117A: Swift-BAT refined analysis
  16. GRB 231118A: GRBAlpha detection
  17. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  18. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  19. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  20. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  21. GRB 231118A: VZLUSAT-2 detection
  22. GRB 231117A: AMI-LA radio observations
  23. GRB 231118A: Swift-BAT refined analysis
  24. Konus-Wind detection of GRB 231020A
  25. GRB 231117A: LDT Confirmation of Optical Fading
  26. GRB 231117A: Wendelstein Confirmation of Fading of the Optical Afterglow
  27. GRB 231118B: CALET Gamma-Ray Burst Monitor detection
  28. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  29. 231118A: Swift-UVOT Detection
  30. GRB231117A: Swift-UVOT detection
  31. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  32. GRB 231118B: Fermi GBM observation
  33. GRB 231118A: Fermi GBM observation
  34. GRB 231120A: Fermi GBM Final Real-time Localization
  35. GRB 231117A: Swift-XRT refined Analysis
  36. GRB 231118A: Swift-XRT refined Analysis
  37. GRB 231118A: MeerLICHT afterglow detection
  38. GRB 231117A: OHP/T120 optical observations
  39. GRB 231118A: VLT/X-shooter redshift
  40. GRB 231117A: Pan-STARRS1 follow-up confirms rapid fading
  41. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  42. GRB 231117A: AKO Follow-Up Observation
  43. GRB 231117A: GECAM-C detection
  44. GRB 231118A: AstroSat CZTI detection
  45. GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
  46. GRB 231117A: 10 GHz VLA detection
  47. GRB 231118A: Las Cumbres optical detection
  48. GRB 231118B: BALROG localization (Fermi Trigger 722039659 / GRB 231118940)
  49. GRB 231118B: Fermi GBM Final Real-time Localization
  50. GRB 231118A: LCOGT Optical Observations
  51. GRB 231118A: MASTER OT observation
  52. GRB 231118A: Continued Skynet Observations
  53. GRB 231118A: Enhanced Swift-XRT position
  54. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  55. GRB 231118A: Swift-XRT position
  56. GRB 231118A: Skynet Optical Afterglow Discovery
  57. GRB 231117A: SOAR/Goodman imaging of the afterglow
  58. GRB 231118A: Swift detection of a burst
  59. GRB 231118A: Fermi GBM Final Real-time Localization
  60. GRB 231117A: Lowell Discovery Telescope Observations
  61. GRB 231117A: ePESSTO+ host galaxy redshift confirmation
  62. GRB 231117A: ATCA detection of a radio counterpart
  63. GRB 231117A: GRBAlpha detection
  64. GRB 231117A: Keck spectroscopy of afterglow candidate
  65. GRB 231115A: Wendelstein Optical/Infrared Observations
  66. GRB 231115A: JinShan optical upper limits
  67. GRB 231117A: GIT optical follow-up
  68. GRB 231117A: LT observations consistent with fading
  69. GRB 231117A: Keck observations indicate presence of optical afterglow in z~0.3-0.5 galaxy
  70. GRB 231117A: REM optical and NIR early-time observations
  71. GRB231117A: AGILE/MCAL analysis
  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 : OHP/T120 optical upper limit
  79. GRB 231115A: optical observations from INAF observatories
  80. GRB 231117A : MITSuME Akeno optical upper limits
  81. GRB 231117A: AGILE detection of a bright short burst
  82. GRB 231117A: Enhanced Swift-XRT position
  83. GRB 231117A: GOTO optical upper limits
  84. GRB 231117A: AstroSat CZTI detection of a bright short burst
  85. GRB 231117A: Swift detection of a bright short burst
  86. GRB 231115A: Non-detection of radio emission with CHIME/FRB
  87. GRB 231111A: Swift/UVOT Detection
  88. MAGIC observation of GRB 231115A, a possible magnetar giant flare
  89. GRB231115A: Liverpool Telescope imaging
  90. GRB 231115A: NuSTAR Follow-Up Observations
  91. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  92. GRB 231115A: Swift-XRT and Swift-UVOT observations
  93. Fermi GRB 231116A: Global MASTER-Net observations report
  94. Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
  95. GRB 231115A: AGILE/MCAL upper limits
  96. GRB 231115A: Insight-HXMT/HE detection
  97. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  98. GRB 231116A: Fermi GBM Final Real-time Localization
  99. GRB 231115A : MITSuME Akeno and Okayama optical upper limits
  100. GRB 231115A: Gaoyazi/GOT follow-up and archival observations

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