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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"

28231 results found.

  1. Fermi-LAT gamma-ray observations of IceCube-221104A
  2. GRB 221027B: GRANDMA observations
  3. GRB 221028A: Detection by VZLUSAT-2
  4. GRB 221029A: Fermi GBM observation
  5. GRB 221029A: Fermi GBM Final Localization
  6. GRB 221028A: Swift-XRT refined Analysis
  7. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  8. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  9. GRB 221028A: Correction to GCN 32893 - Fluence and flux are for 50-150 keV
  10. GRB 221028A, Swift-BAT refined analysis
  11. GRB 221027B: Swift-BAT refined analysis
  12. GRB 221029A: Swift/BAT-GUANO detection outside the coded FOV
  13. GRB 221028A: CrAO/ZTSh optical upper limit
  14. GRB 221028A: COATLI Upper Limits
  15. Trigger 1132968: Swift trigger is the Crab
  16. GRB 221028A: MITSuME Okayama optical upper limits
  17. GRB 221028B: MAXI/GSC detection
  18. GRB 221028A: LCOGT Optical Upper Limits
  19. GRB 221027B: COATLI Upper Limits
  20. GRB 221028A: GIT optical upper limit
  21. GRB 221027B: Swift/UVOT Upper Limits
  22. GRB 221028A: Swift detection of a burst
  23. GRB 221027B: Swift-XRT refined Analysis
  24. GRB 221027B: BOOTES-1 optical upper limit
  25. GRB 221027B: Enhanced Swift-XRT position
  26. GRB 221027B: Swift detection of a burst
  27. GRB 221027A: Fermi GBM detection
  28. GRB 221024A: Mondy optical observations
  29. GRB 221027A: Fermi-LAT detection
  30. GRB 221024A: GRANDMA observations
  31. IPN triangulation of GRB 221022C (short)
  32. GRB 221023A: AGILE/GRID analysis
  33. GRB 221024A: Swift-BAT refined analysis
  34. GRB 221025A: AstroSat CZTI detection
  35. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  36. GRB 221025A: Fermi GBM Observation
  37. GRB 221024A: Swift/UVOT UV upper limits
  38. GRB 221022A: Swift-XRT observations
  39. GRB 221024A: Swift-XRT refined Analysis
  40. GRB 221023A: Fermi GBM Observation
  41. GRB 221025A: Fermi-LAT detection
  42. IPN triangulation of GRB 221022B (long)
  43. GRB 221024A: GIT confirmation of the optical afterglow
  44. GRB 221024A: Enhanced Swift-XRT position
  45. GRB 221024A: D50 candidate afterglow
  46. GRB 221022A: Fermi GBM detection
  47. GRB 221023A: Fermi-LAT detection
  48. GRB 221022B: Fermi GBM detection
  49. GRB 221021A: Fermi GBM observation
  50. GRB 221024A: Swift detection of a burst
  51. GRB 221023A: Fermi GBM Final Localization
  52. GRB 221022A: Swift/BAT-GUANO detection
  53. GRB 221022B: Swift/BAT-GUANO detection outside the coded FOV
  54. GRB 221009A: Analysis of the initial episode using data of GBM/Fermi and SPI-ACS/INTEGRAL
  55. GRB 221021A: Swift/BAT-GUANO detection outside the coded FOV
  56. SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
  57. GRB221009A: LBT optical imaging
  58. GRB 221009A: Peak luminosity of the supernova vs. synchrotron afterglow
  59. GRB 221017A: Swift-XRT observations
  60. GRB 221009A: TNG NIR detection
  61. GRB 221009A: BOAO NIR detections
  62. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  63. GRB 221013B: Swift/BAT-GUANO detection
  64. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  65. GRB 221009A: GRANDMA observations
  66. The probability of observing GRB 221009A at z = 0.151
  67. GRB 221009A: Medicina Radio Telescope observations
  68. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  69. GRB 221009A: Second epoch of NuSTAR data
  70. GRB 221016A: Swift-BAT refined analysis
  71. GRB 221016A: Swift/UVOT Detection
  72. GRB 221016A: Swift-XRT refined Analysis
  73. GRB 221016A: Fermi GBM observation
  74. GRB 221009A: A type I BdHN of exceptional energetics
  75. MAXI GRB221017.24: Global MASTER-Net observations report
  76. GRB 221016A: z-band upper limit, possible afterglow brightening
  77. GRB 221017A: MAXI/GSC detection
  78. GRB 221016A: Enhanced Swift-XRT position
  79. GRB 221016A: LCOGT Optical Afterglow Detection
  80. GRB 221016A: Swift detection of a burst
  81. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up
  82. Konus-Wind observation of the recent SGR 1935+2154 activity
  83. GRB 221009A: VLT spectroscopic detection of the host galaxy
  84. GRB 221009A: Armchair Energetics
  85. GRB 221009A: ALMA and ACA detections
  86. GRB 221009A: Large Binocular Telescope Observatory optical afterglow 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: OHP optical observations
  90. MAXI GRB 221006A: Redshifts of the possible host galaxies
  91. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  92. GRB 221009A/Swift J1913.1+1946: low-frequency ASKAP observations
  93. GRB 221006A: Swift-XRT afterglow detection
  94. GRB 221009A: MITSuME Okayama optical observation
  95. GRB 221009A: Sayan observatory 1.6-m telescope observations
  96. GRB 221009A: GMG observation
  97. Afterglow limits of GRB 221006A from OHP
  98. GRB221009A: optical afterglow measurements from Konkoly Observatory
  99. GRB 221009A/Swift J1913.1+1946: SMA observations
  100. INTEGRAL shows increasing activity in SGR J1935+2154

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