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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"

39404 results found.

  1. GRB 221025A: Fermi GBM Observation
  2. GRB 221009A: spectroscopic confirmation of SN in LBT spectra
  3. Konus-Wind detection of GRB 221023A
  4. GRB 221024A: Swift/UVOT UV upper limits
  5. GRB 221022A: Swift-XRT observations
  6. GRB 221024A: Swift-XRT refined Analysis
  7. GRB 221023A: Fermi GBM Observation
  8. GRB 221022B: Detection by GRBAlpha
  9. GRB 221025A: Fermi-LAT detection
  10. IPN triangulation of GRB 221022B (long)
  11. GRB 221024A: GIT confirmation of the optical afterglow
  12. LAT GRB221025.04: Global MASTER-Net observations report
  13. GRB 221024A: Enhanced Swift-XRT position
  14. GRB 221024A: D50 candidate afterglow
  15. GRB 221022B: AstroSat CZTI detection
  16. GRB 221022A: Fermi GBM detection
  17. GRB 221022A: Swift ToO observations
  18. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  19. GRB 221023A: Fermi-LAT detection
  20. GRB 221022B: Fermi GBM detection
  21. GRB 221021A: Fermi GBM observation
  22. GRB 221009A: Determination of the black holes mass and spin
  23. GRB 221024A: Swift detection of a burst
  24. GRB 221023A: Fermi GBM Final Localization
  25. GRB 221023A: AGILE detection of a burst
  26. GRB 221022A: Swift/BAT-GUANO detection
  27. GRB 221022B: Swift/BAT-GUANO detection outside the coded FOV
  28. GRB 221022B: AGILE detection
  29. GRB 221009A: James Webb Space Telescope Observations
  30. GRB 221022B: Fermi GBM Final Real-time Localization
  31. GRB 221009A: Analysis of the initial episode using data of GBM/Fermi and SPI-ACS/INTEGRAL
  32. GRB 221009A: optical observations, SN photometric evidence
  33. GRB 221021A: Swift/BAT-GUANO detection outside the coded FOV
  34. GRB 221022A: Fermi GBM Final Real-time Localization
  35. GRB 221020A: Detection by GRBAlpha
  36. SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
  37. GRB 221017A: CALET Gamma-Ray Burst Monitor detection
  38. GRB 221021A: Fermi GBM Final Real-time Localization
  39. GRB 221009A: 1.3m DFOT Optical Observations
  40. Fermi GBM trigger 687320613 / 221013100 (GRB 221013B) is not a GRB
  41. GRB221009A: LBT optical imaging
  42. GRB 221009A: Peak luminosity of the supernova vs. synchrotron afterglow
  43. GRB 221017A: Swift-XRT observations
  44. GRB 221020A: Fermi GBM Final Real-time Localization
  45. Improved IPN localization for GRB 221009A (BepiColombo-MGNS light curve)
  46. GRB 221009A: TNG NIR detection
  47. GRB 221009A: BOAO NIR detections
  48. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  49. GRB 221009A: Spectroscopic detection of emerging SN features
  50. GRB 221009A: Continued LDT Afterglow Monitoring
  51. GRB 221013B: Swift/BAT-GUANO detection
  52. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  53. GRB 221009A: GRANDMA observations
  54. The probability of observing GRB 221009A at z = 0.151
  55. GRB 221009A: Medicina Radio Telescope observations
  56. GRB 221017A: Swift ToO observations
  57. GRB 221009A: Second epoch of NuSTAR data
  58. IPN triangulation of GRB 221017A (long)
  59. GRB 221016A: Swift-BAT refined analysis
  60. GRB 221016A: Swift/UVOT Detection
  61. GRB 221016A: Swift-XRT refined Analysis
  62. Konus-Wind detection of GRB 221016A
  63. GRB 221016A: Fermi GBM observation
  64. GRB 220926B: Detection by GRBAlpha
  65. GRB 221009A: A type I BdHN of exceptional energetics
  66. MAXI GRB221017.24: Global MASTER-Net observations report
  67. GRB 221016A: z-band upper limit, possible afterglow brightening
  68. GRB 221017A: MAXI/GSC detection
  69. GRB 221016A: Enhanced Swift-XRT position
  70. GRB 221016A: LCOGT Optical Afterglow Detection
  71. GRB 221016A: Swift detection of a burst
  72. GRB 221016A: Fermi GBM Final Real-time Localization
  73. Swift GRB221016.99: Global MASTER-Net observations report
  74. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up
  75. GRB 221009A: continued Assy optical afterglow observations, possible SN evidence
  76. GRB 221009A: LEIA X-ray Afterglow Detection
  77. GRB 221009A: ATCA radio spectrum
  78. GRB 221009A: VLT spectroscopic detection of the host galaxy
  79. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  80. GRB 221009A: ATCA detection
  81. GRB 221009A: Armchair Energetics
  82. GRB 221009A: ALMA and ACA detections
  83. GRB 221009A: Fermi LAT data rate effects due to extremely high flux
  84. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  85. GRB 221009A: Pan-STARRS optical photometry
  86. GRB 221009A: VLA detection
  87. MAXI/GSC refined analysis of the bright X-ray afterglow of GRB 221009A/Swift J1913.1+1946
  88. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  89. GRB 221009A: IXPE preliminary upper limits of X-ray polarization
  90. GRB 221009A: OHP optical observations
  91. GRB221009A: RTT-150 optical observations
  92. GRB 221009A: HEBS detection
  93. GRB 221009A: Gemini-South Infrared Afterglow Detection
  94. GRB221009A: Gemini-South Optical Afterglow Detection
  95. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  96. GRB 221014A: Fermi GBM Final Real-time Localization
  97. GRB 221009A: Gamma-ray Detection by SIRI-2
  98. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  99. MAXI GRB 221006A: Redshifts of the possible host galaxies
  100. GRB 221009A: search for neutrinos with KM3NeT

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