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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').
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"

28057 results found.

  1. IPN localization of bright GRB 110518A
  2. GRB 110519A, Swift-BAT refined analysis
  3. GRB 110519A: Swift detection of a burst
  4. GRB 110426A: Fermi GBM detection
  5. GRB 110428A: Fermi-GBM observation
  6. GRB 110503A: TAROT Calern observatory optical observations
  7. Konus-Wind observation of GRB 110503A
  8. GRB 110503A: optical observation in CrAO
  9. GRB 110503A: Centimeter observation from EVLA
  10. GRB 110503A: Millimeter observation from SMA
  11. GRB 110503A: SARA-N Observations and Photometric Calibration
  12. GRB 110503A: Swift/UVOT Observations
  13. GRB 110503A: Swift-XRT refined Analysis
  14. GRB 110503A: PAIRITEL NIR Detection
  15. GRB 110503A: Swift-BAT refined analysis
  16. GRB 110503A: Enhanced Swift-XRT position
  17. GRB 110503A: Swift detection of a burst with a bright optical counterpart
  18. GRB 110426A: Swift/XRT non-detection
  19. GRB 110428A : X-ray afterglow confirmation
  20. GRB 110428A: Suzaku WAM observation of the prompt emission
  21. GRB 110422A: optical observations in CrAO
  22. GRB 110428A : Swift-XRT observations
  23. GRB 110426A: MASTER synchronous with MAXI/GSC observations
  24. GRB 110422A: optical observations in CrAO, second epoch
  25. GRB 110422A: Suzaku WAM observation of the prompt emission
  26. GRB110422A: NOT optical follow-ups
  27. GRB 110422A: optical observations in CrAO
  28. GRB110422A: MITSuME Ishigakijima Optical Observation
  29. GRB 110422A: Further NOT observation
  30. GRB 110422A: Swift/UVOT Detection of optical afterglow
  31. GRB 110422A: Swift-XRT refined Analysis
  32. GRB 110422A: Enhanced Swift-XRT position
  33. GRB 110422A: TNG optical observations
  34. GRB 110422A: SAO RAS optical observations
  35. GRB 110422A: NOT optical observation
  36. GRB 110422A: Swift-BAT refined analysis
  37. GRB 110422A: Mondy optical observations
  38. GRB 110422A: Swift detection of a burst
  39. GRB 110420B: Swift/UVOT Upper Limits
  40. GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
  41. GRB 110420B: Swift-XRT afterglow candidate retraction
  42. GRB 110420B, GROND observations
  43. GRB 110420A Swift/UVOT Observations
  44. GRB 110420B: Swift-XRT afterglow candidate
  45. GRB 110420B: Swift-BAT refined analysis
  46. GRB 110420A: Swift-BAT refined analysis
  47. GRB 110420A: Swift-XRT refined Analysis
  48. GRB 110420A: Enhanced Swift-XRT position
  49. GRB 110420A: Swift detection of a burst with optical counterpart
  50. GRB110414A: MITSuME Ishigakijima Optical upper limits
  51. GRB 110414A: GROND upper limits
  52. GRB110414A: MITSuME Okayama Optical upper limits
  53. GRB 110414A: Swift-BAT Refined Analysis
  54. GRB 110414A: Swift/UVOT Upper limits
  55. GRB 110414A: Swift-XRT refined Analysis
  56. GRB 110414A: Enhanced Swift-XRT position
  57. GRB 110328A / Swift J164449.3+573451: WISE quiescent source upper limit
  58. GRB 110414A : Faulkes Telescope North observations
  59. GRB 110414A: Swift detection of a burst
  60. GRB 110411A: PAIRITEL NIR Upper Limits
  61. GRB 110412A: Swift-BAT refined analysis
  62. GRB 110411A: Swift-XRT refined Analysis
  63. GRB 110411A: Swift/UVOT Upper Limits
  64. GRB 110411A : Xinglong TNT OT candidate
  65. GRB 110411A, Swift-BAT refined analysis
  66. GRB 110411A: Enhanced Swift-XRT position
  67. GRB 110411A: Swift detection of a burst
  68. GRB 110407A: Swift-XRT refined Analysis
  69. GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
  70. GRB 110328A / Swift J164449.3+573451: optical observations
  71. GRB 110328A/Swift J164449.3+573451 UVOT Upper Limits
  72. GRB 110406A: Positional coincidence with NGC 404
  73. GRB110407A: UVOT Upper Limits
  74. GRB 110407A: GROND Detection of the Optical Afterglow
  75. GRB 110407A: MITSuME Okayama and Ishigakijima Optical upper limits
  76. GRB 110407A: NOT optical observations
  77. GRB 110407A: Enhanced Swift-XRT position
  78. GRB 110407A: Swift-BAT refined analysis
  79. GRB 100407A : Errata of afterglow position in GCN 11899
  80. IPN triangulation of the bright GRB110406A
  81. GRB 110407A : Lulin optical afterglow detection
  82. GRB 110407A: Swift detection of a burst
  83. Konus-Wind observation of GRB 110406A
  84. GRB 110328A/Swift J164449.3+573451: BAT recent rate increase and pre-outburst,light curve
  85. GRB 110402A: fading optical afterglow
  86. GRB 110402A: Suzaku WAM observation of the prompt emission
  87. GRB 110402A: LOAO Optical Observation
  88. GRB 110328A / Swift J164449.3+573451, HST Observations
  89. GRB 110402A: Konus-Wind spectral lags and detailed energetics
  90. GRB 110401A: Fermi GBM detection
  91. GRB 110402A: Fermi GBM detection
  92. GRB 110402A: optical observations in Mondy
  93. GRB 110402A afterglow observation
  94. GRB 110328A / Swift J164449.3+573451: Keck/DEIMOS Optical Spectroscopy
  95. GRB 110402A: MITSuME Okayama and Ishigakijima Optical upper limits
  96. GRB 110328A/Swift J164449.3+573451: SARA-N detection
  97. GRB 110402A: Swift/UVOT detection of afterglow candidate
  98. GRB 110402A: Konkoly observations
  99. GRB 110328A: Konkoly observations.
  100. GRB 110402A: Swift-BAT refined analysis

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