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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

37362 results found.

  1. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  2. GRB 231117A: Chandra afterglow detection
  3. GRB 231123A: Fermi GBM Final Real-time Localization
  4. GRB 231122B: Glowbug gamma-ray detection
  5. GRB 231117A: Continued GTC Observations
  6. GRB 231122A: GECAM detection
  7. GRB 231122B: GECAM detection
  8. GRB 231122A: Fermi GBM Final Real-time Localization
  9. GRB 231118A: ATCA detection of radio counterpart
  10. GRB 231117A: Swift/UVOT late time observations
  11. GRB 231117A: GTC Near-Infrared Observations
  12. GRB 231117A: Swift-BAT refined analysis
  13. GRB 231118A: GRBAlpha detection
  14. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  15. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  16. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  17. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  18. GRB 231118A: VZLUSAT-2 detection
  19. GRB 231117A: AMI-LA radio observations
  20. GRB 231118A: Swift-BAT refined analysis
  21. Konus-Wind detection of GRB 231020A
  22. GRB 231117A: LDT Confirmation of Optical Fading
  23. GRB 231117A: Wendelstein Confirmation of Fading of the Optical Afterglow
  24. GRB 231118B: CALET Gamma-Ray Burst Monitor detection
  25. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  26. 231118A: Swift-UVOT Detection
  27. GRB231117A: Swift-UVOT detection
  28. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  29. GRB 231118B: Fermi GBM observation
  30. GRB 231118A: Fermi GBM observation
  31. LIGO/Virgo/KAGRA S231119ab: Coverage and upper limits from MAXI/GSC observations
  32. GRB 231120A: Fermi GBM Final Real-time Localization
  33. GRB 231117A: Swift-XRT refined Analysis
  34. GRB 231118A: Swift-XRT refined Analysis
  35. GRB 231118A: MeerLICHT afterglow detection
  36. LIGO/Virgo/KAGRA S231119u: One counterpart neutrino candidate from IceCube neutrino searches
  37. GRB 231117A: OHP/T120 optical observations
  38. GRB 231118A: VLT/X-shooter redshift
  39. GRB 231117A: Pan-STARRS1 follow-up confirms rapid fading
  40. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  41. GRB 231117A: AKO Follow-Up Observation
  42. GRB 231117A: GECAM-C detection
  43. GRB 231118A: AstroSat CZTI detection
  44. GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
  45. GRB 231117A: 10 GHz VLA detection
  46. GRB 231118A: Las Cumbres optical detection
  47. GRB 231118B: BALROG localization (Fermi Trigger 722039659 / GRB 231118940)
  48. GRB 231118B: Fermi GBM Final Real-time Localization
  49. GRB 231118A: LCOGT Optical Observations
  50. GRB 231118A: MASTER OT observation
  51. GRB 231118A: Continued Skynet Observations
  52. GRB 231118A: Enhanced Swift-XRT position
  53. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  54. GRB 231118A: Swift-XRT position
  55. GRB 231118A: Skynet Optical Afterglow Discovery
  56. GRB 231117A: SOAR/Goodman imaging of the afterglow
  57. GRB 231118A: Swift detection of a burst
  58. GRB 231118A: Fermi GBM Final Real-time Localization
  59. GRB 231117A: Lowell Discovery Telescope Observations
  60. GRB 231117A: ePESSTO+ host galaxy redshift confirmation
  61. GRB 231117A: ATCA detection of a radio counterpart
  62. GRB 231117A: GRBAlpha detection
  63. GRB 231117A: Keck spectroscopy of afterglow candidate
  64. GRB 231115A: Wendelstein Optical/Infrared Observations
  65. GRB 231115A: JinShan optical upper limits
  66. GRB 231117A: GIT optical follow-up
  67. GRB 231117A: LT observations consistent with fading
  68. GRB 231117A: Keck observations indicate presence of optical afterglow in z~0.3-0.5 galaxy
  69. GRB 231117A: REM optical and NIR early-time observations
  70. GRB231117A: AGILE/MCAL analysis
  71. GRB 231117A: AKO Optical Upper Limit
  72. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  73. Swift GRB 231117A: Global MASTER-Net observations report
  74. GRB 231117A (short): Glowbug gamma-ray detection
  75. GRB 231117A: ATLAS non-detection of an optical counterpart
  76. Konus-Wind detection of GRB 231117A (short/hard)
  77. GRB 231115A : OHP/T120 optical upper limit
  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 231115A: Non-detection of radio emission with CHIME/FRB
  86. GRB 231111A: Swift/UVOT Detection
  87. MAGIC observation of GRB 231115A, a possible magnetar giant flare
  88. GRB231115A: Liverpool Telescope imaging
  89. GRB 231115A: NuSTAR Follow-Up Observations
  90. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  91. GRB 231115A: Swift-XRT and Swift-UVOT observations
  92. Fermi GRB 231116A: Global MASTER-Net observations report
  93. Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
  94. GRB 231115A: AGILE/MCAL upper limits
  95. GRB 231115A: Insight-HXMT/HE detection
  96. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  97. GRB 231116A: Fermi GBM Final Real-time Localization
  98. GRB 231115A : MITSuME Akeno and Okayama optical upper limits
  99. GRB 231115A: Gaoyazi/GOT follow-up and archival observations
  100. GRB 231115A / AT2023xvj: Updated GIT analysis

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