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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

27811 results found.

  1. GRB 221020A: Fermi GBM Final Real-time Localization
  2. Improved IPN localization for GRB 221009A (BepiColombo-MGNS light curve)
  3. GRB 221009A: TNG NIR detection
  4. GRB 221009A: BOAO NIR detections
  5. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  6. AGILE detection of a burst from SGR J1935+2154 reported by VZLUSAT-2
  7. GRB 221009A: Spectroscopic detection of emerging SN features
  8. GRB 221013B: Swift/BAT-GUANO detection
  9. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  10. AGILE detection of the 2022 October 17 burst from SGR J1935+2154 reported by Konus-Wind
  11. GRB 221009A: GRANDMA observations
  12. SGR 1935+2154: Detection by GRBAlpha
  13. The probability of observing GRB 221009A at z = 0.151
  14. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 October 17
  15. GRB 221017A: Swift ToO observations
  16. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  17. GRB 221009A: Second epoch of NuSTAR data
  18. IPN triangulation of GRB 221017A (long)
  19. GRB 221016A: Swift-BAT refined analysis
  20. GRB 221016A: Swift/UVOT Detection
  21. GRB 221016A: Swift-XRT refined Analysis
  22. Konus-Wind detection of GRB 221016A
  23. GRB 221016A: Fermi GBM observation
  24. GRB 220926B: Detection by GRBAlpha
  25. GRB 221009A: A type I BdHN of exceptional energetics
  26. GRB 221017A: MAXI/GSC detection
  27. GRB 221016A: Enhanced Swift-XRT position
  28. GRB 221016A: LCOGT Optical Afterglow Detection
  29. GRB 221016A: Swift detection of a burst
  30. GRB 221016A: Fermi GBM Final Real-time Localization
  31. Swift GRB221016.99: Global MASTER-Net observations report
  32. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up
  33. Konus-Wind detection of a short burst coincident with a bright radio burst from SGR 1935+2154
  34. GRB 221009A: continued Assy optical afterglow observations, possible SN evidence
  35. GRB 221009A: LEIA X-ray Afterglow Detection
  36. GRB 221009A: ATCA radio spectrum
  37. GRB 221009A: VLT spectroscopic detection of the host galaxy
  38. GRB 221009A: ATCA detection
  39. GRB 221009A: Armchair Energetics
  40. GRB 221009A: Fermi LAT data rate effects due to extremely high flux
  41. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  42. GRB 221009A: Pan-STARRS optical photometry
  43. GRB 221009A: VLA detection
  44. MAXI/GSC refined analysis of the bright X-ray afterglow of GRB 221009A/Swift J1913.1+1946
  45. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  46. GRB 221009A: HEBS detection
  47. GRB 221009A: Gemini-South Infrared Afterglow Detection
  48. GRB221009A: Gemini-South Optical Afterglow Detection
  49. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  50. GRB 221014A: Fermi GBM Final Real-time Localization
  51. GRB 221009A: Gamma-ray Detection by SIRI-2
  52. GRB221009A: Ionospheric disturbance observed in India
  53. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  54. GRB 221009A: search for neutrinos with KM3NeT
  55. GRB 221009A: MeerKAT detection
  56. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  57. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  58. GRB 221009A/Swift J1913.1+1946: low-frequency ASKAP observations
  59. GRB 221006A: Swift-XRT afterglow detection
  60. GRB 221009A: MITSuME Okayama optical observation
  61. GRB 221009A: Sayan observatory 1.6-m telescope observations
  62. GRB 221013B: Fermi GBM Final Real-time Localization
  63. GRB 221013A: Fermi GBM Final Real-time Localization
  64. GRB 221009A/Swift J1913.1+1946: SMA observations
  65. GRB 221009A/Swift J1913.1+1946: eMERLIN observations
  66. INTEGRAL detection of a burst from SGR J1935+2154
  67. GRB 220829A: Detection by GRBAlpha
  68. GRB 220826B: Detection by GRBAlpha
  69. GRB 221009A: NuSTAR Detection
  70. GRB 221009A: LCOGT Optical Afterglow Detection
  71. GRB 221009A: COATLI Detection of the Afterglow
  72. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  73. GRB 221009A (Swift J1913.1+1946): Swift-BAT refined analysis
  74. GRB 221009A: 10.4m GTC spectroscopic redshift confirmation
  75. GRB 221009A: Detection by GRBAlpha
  76. GRB 221009A: Sintez-Newton/CrAO optical observations
  77. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  78. GRB 221006A: Swift ToO observations
  79. GRB 221011A: Fermi GBM Final Real-time Localization
  80. Swift/XRT discovery of multiple dust-scattering X-ray rings around GRB 221009A
  81. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  82. LHAASO observed GRB 221009A with more than 5000 VHE photons up to around 18 TeV
  83. GRB 221009A: NOEMA mm detection
  84. INTEGRAL detection of a burst from SGR J1935+2154
  85. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  86. GRB 221009A: Continued Swift/XRT observations
  87. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  88. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  89. Konus-Wind detection of GRB 221009A
  90. GRB 221009A: Lulin SLT-40cm optical observations
  91. Swift J1913.1+1946: New Photometry
  92. GRB 221009A: Upper limits from a neutrino search with IceCube
  93. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  94. GRB221009A/Swift J1913.1+1946: SRG/ART-XC observation
  95. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  96. GRB221009A/Swift J1913.1+1946: Solar Orbiter STIX measurements
  97. GRB221009A/Swift J1913.1+1946: INTEGRAL SPI/ACS observations
  98. ​GRB 221009A: Multi-color detection of the optical
  99. GRB 221009A: Fermi-LAT refined analysis
  100. GRB 221009A (Swift J1913.1+1946): AGILE/GRID detection

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