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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"

35947 results found.

  1. GRB 221028A: HCT optical upper limit
  2. GRB 221028A: AGILE detection
  3. GRB 221027A: AGILE detection
  4. GRB 221028A: MITSuME Okayama optical upper limits
  5. GRB 221028B: MAXI/GSC detection
  6. GRB 221028A: LCOGT Optical Upper Limits
  7. GRB 221027B: COATLI Upper Limits
  8. Swift GRB 221028A: Global MASTER-Net observations report
  9. GRB 221028A: BOOTES-4/MET optical upper limit
  10. LIGO-Virgo-KAGRA and GEO600 statement on GRB 221009A
  11. GRB 221028A: GIT optical upper limit
  12. GRB 221027B: Swift/UVOT Upper Limits
  13. GRB 221028A: Swift detection of a burst
  14. GRB 221027B: FRAM-ORM and Ondrejov SBT optical limits
  15. Konus-Wind detection of GRB 221017A
  16. Swift GRB 221027B: Global MASTER-Net observations report
  17. GRB 221027B: Swift-XRT refined Analysis
  18. GRB 221027B: BOOTES-1 optical upper limit
  19. GRB 221027B: Enhanced Swift-XRT position
  20. GRB 221027B: Swift detection of a burst
  21. GRB 221027A: Fermi GBM detection
  22. IPN triangulation of GRB 221025A (short)
  23. Konus-Wind detection of GRB 221022B
  24. GRB 221024A: Mondy optical observations
  25. GRB 221027A: Fermi-LAT detection
  26. GRB 221027A: Fermi GBM Final Real-time Localization
  27. GRB 221009A: Further Gemini-South Infrared Observations
  28. GRB 221024A: GRANDMA observations
  29. Fermi Gamma-ray Burst Monitor trigger 688431261/221025954 is not a GRB
  30. IPN triangulation of GRB 221022C (short)
  31. GRB 221023A: AGILE/GRID analysis
  32. GRB 221024A: Swift-BAT refined analysis
  33. GRB 221025A: AstroSat CZTI detection
  34. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  35. GRB 221025A: Fermi GBM Observation
  36. GRB 221009A: spectroscopic confirmation of SN in LBT spectra
  37. Konus-Wind detection of GRB 221023A
  38. GRB 221024A: Swift/UVOT UV upper limits
  39. GRB 221022A: Swift-XRT observations
  40. GRB 221024A: Swift-XRT refined Analysis
  41. GRB 221023A: Fermi GBM Observation
  42. GRB 221022B: Detection by GRBAlpha
  43. GRB 221025A: Fermi-LAT detection
  44. IPN triangulation of GRB 221022B (long)
  45. GRB 221024A: GIT confirmation of the optical afterglow
  46. GRB 221024A: Enhanced Swift-XRT position
  47. GRB 221024A: D50 candidate afterglow
  48. GRB 221022B: AstroSat CZTI detection
  49. GRB 221022A: Fermi GBM detection
  50. GRB 221022A: Swift ToO observations
  51. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  52. GRB 221023A: Fermi-LAT detection
  53. GRB 221022B: Fermi GBM detection
  54. GRB 221021A: Fermi GBM observation
  55. GRB 221009A: Determination of the black holes mass and spin
  56. GRB 221024A: Swift detection of a burst
  57. GRB 221023A: Fermi GBM Final Localization
  58. GRB 221023A: AGILE detection of a burst
  59. GRB 221022A: Swift/BAT-GUANO detection
  60. GRB 221022B: Swift/BAT-GUANO detection outside the coded FOV
  61. GRB 221022B: AGILE detection
  62. GRB 221009A: James Webb Space Telescope Observations
  63. GRB 221022B: Fermi GBM Final Real-time Localization
  64. GRB 221009A: Analysis of the initial episode using data of GBM/Fermi and SPI-ACS/INTEGRAL
  65. GRB 221009A: optical observations, SN photometric evidence
  66. GRB 221021A: Swift/BAT-GUANO detection outside the coded FOV
  67. GRB 221022A: Fermi GBM Final Real-time Localization
  68. GRB 221020A: Detection by GRBAlpha
  69. SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
  70. GRB 221017A: CALET Gamma-Ray Burst Monitor detection
  71. GRB 221021A: Fermi GBM Final Real-time Localization
  72. GRB 221009A: 1.3m DFOT Optical Observations
  73. Fermi GBM trigger 687320613 / 221013100 (GRB 221013B) is not a GRB
  74. GRB221009A: LBT optical imaging
  75. GRB 221009A: Peak luminosity of the supernova vs. synchrotron afterglow
  76. GRB 221017A: Swift-XRT observations
  77. GRB 221020A: Fermi GBM Final Real-time Localization
  78. Improved IPN localization for GRB 221009A (BepiColombo-MGNS light curve)
  79. GRB 221009A: TNG NIR detection
  80. GRB 221009A: BOAO NIR detections
  81. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  82. GRB 221009A: Spectroscopic detection of emerging SN features
  83. GRB 221009A: Continued LDT Afterglow Monitoring
  84. GRB 221013B: Swift/BAT-GUANO detection
  85. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  86. GRB 221009A: GRANDMA observations
  87. The probability of observing GRB 221009A at z = 0.151
  88. GRB 221009A: Medicina Radio Telescope observations
  89. GRB 221017A: Swift ToO observations
  90. GRB 221009A: Second epoch of NuSTAR data
  91. IPN triangulation of GRB 221017A (long)
  92. GRB 221016A: Swift-BAT refined analysis
  93. GRB 221016A: Swift/UVOT Detection
  94. GRB 221016A: Swift-XRT refined Analysis
  95. Konus-Wind detection of GRB 221016A
  96. GRB 221016A: Fermi GBM observation
  97. GRB 220926B: Detection by GRBAlpha
  98. GRB 221009A: A type I BdHN of exceptional energetics
  99. GRB 221016A: z-band upper limit, possible afterglow brightening
  100. GRB 221017A: MAXI/GSC detection

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