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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"

28737 results found.

  1. Fermi GBM trigger 687320613 / 221013100 (GRB 221013B) is not a GRB
  2. GRB221009A: LBT optical imaging
  3. GRB 221009A: Peak luminosity of the supernova vs. synchrotron afterglow
  4. GRB 221017A: Swift-XRT observations
  5. Improved IPN localization for GRB 221009A (BepiColombo-MGNS light curve)
  6. GRB 221009A: TNG NIR detection
  7. GRB 221009A: BOAO NIR detections
  8. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  9. AGILE detection of a burst from SGR J1935+2154 reported by VZLUSAT-2
  10. GRB 221009A: Spectroscopic detection of emerging SN features
  11. GRB 221009A: Continued LDT Afterglow Monitoring
  12. GRB 221013B: Swift/BAT-GUANO detection
  13. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  14. AGILE detection of the 2022 October 17 burst from SGR J1935+2154 reported by Konus-Wind
  15. GRB 221009A: GRANDMA observations
  16. SGR 1935+2154: Detection by GRBAlpha
  17. GRB 221009A: Medicina Radio Telescope observations
  18. GRB 221017A: Swift ToO observations
  19. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  20. GRB 221009A: Second epoch of NuSTAR data
  21. IPN triangulation of GRB 221017A (long)
  22. GRB 221016A: Swift-BAT refined analysis
  23. GRB 221016A: Swift/UVOT Detection
  24. GRB 221016A: Swift-XRT refined Analysis
  25. Konus-Wind detection of GRB 221016A
  26. GRB 221016A: Fermi GBM observation
  27. GRB 220926B: Detection by GRBAlpha
  28. GRB 221016A: z-band upper limit, possible afterglow brightening
  29. GRB 221016A: LCOGT Optical Afterglow Detection
  30. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up
  31. Konus-Wind detection of a short burst coincident with a bright radio burst from SGR 1935+2154
  32. GRB 221009A: continued Assy optical afterglow observations, possible SN evidence
  33. Konus-Wind observation of the recent SGR 1935+2154 activity
  34. GRB 221009A: LEIA X-ray Afterglow Detection
  35. GRB 221009A: ATCA radio spectrum
  36. GRB 221009A: VLT spectroscopic detection of the host galaxy
  37. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  38. GRB 221009A: ATCA detection
  39. GRB 221009A: Armchair Energetics
  40. GRB 221009A: ALMA and ACA detections
  41. GRB 221009A: Fermi LAT data rate effects due to extremely high flux
  42. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  43. GRB 221009A: Pan-STARRS optical photometry
  44. GRB 221009A: VLA detection
  45. MAXI/GSC refined analysis of the bright X-ray afterglow of GRB 221009A/Swift J1913.1+1946
  46. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  47. GRB 221009A: OHP optical observations
  48. GRB221009A: RTT-150 optical observations
  49. GRB 221009A: HEBS detection
  50. GRB 221009A: Gemini-South Infrared Afterglow Detection
  51. GRB221009A: Gemini-South Optical Afterglow Detection
  52. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  53. GRB 221009A: Gamma-ray Detection by SIRI-2
  54. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  55. GRB221009A: RTT-150 optical observations
  56. MAXI GRB 221006A: Redshifts of the possible host galaxies
  57. GRB 221009A: search for neutrinos with KM3NeT
  58. GRB 221009A: MeerKAT detection
  59. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  60. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  61. Fermi Gamma-ray Burst Monitor continues to detect SGR 1935+2154
  62. GRB 221009A/Swift J1913.1+1946: low-frequency ASKAP observations
  63. GRB 221006A: Swift-XRT afterglow detection
  64. GRB 221009A: MITSuME Okayama optical observation
  65. GRB 221009A: Sayan observatory 1.6-m telescope observations
  66. GRB 221009A: GMG observation
  67. Afterglow limits of GRB 221006A from OHP
  68. GRB221009A: optical afterglow measurements from Konkoly Observatory
  69. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  70. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  71. INTEGRAL detection of a burst from SGR J1935+2154
  72. GRB 221009A: NuSTAR Detection
  73. GRB 221009A: NICER follow-up observations
  74. GRB 221009A: LCOGT Optical Afterglow Detection
  75. GRB 221009A: COATLI Detection of the Afterglow
  76. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  77. GRB 221009A (Swift J1913.1+1946): Swift-BAT refined analysis
  78. GRB 221009A: Detection by GRBAlpha
  79. GRB 221009A: Sintez-Newton/CrAO optical observations
  80. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  81. GRB 221006A: Swift ToO observations
  82. Swift/XRT discovery of multiple dust-scattering X-ray rings around GRB 221009A
  83. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  84. GRB 221009A: BlackGEM optical observations
  85. LHAASO observed GRB 221009A with more than 5000 VHE photons up to around 18 TeV
  86. GRB 221009A: NOEMA mm detection
  87. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  88. GRB 221009A: Continued Swift/XRT observations
  89. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  90. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  91. Konus-Wind detection of GRB 221009A
  92. GRB 221009A: Lulin SLT-40cm optical observations
  93. Swift J1913.1+1946: New Photometry
  94. GRB 221009A: Upper limits from a neutrino search with IceCube
  95. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  96. GRB221009A/Swift J1913.1+1946: SRG/ART-XC observation
  97. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  98. GRB221009A/Swift J1913.1+1946: INTEGRAL SPI/ACS observations
  99. ​GRB 221009A: Multi-color detection of the optical
  100. GRB 221009A: Fermi-LAT refined analysis

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