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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"

28061 results found.

  1. GRB 110520A: WHT IR observations
  2. GRB 110520A - NOT optical observation
  3. GRB 110520A: TAROT Calern observatory optical observations
  4. GRB 110520A: Swift detection of a burst
  5. IPN localization of bright GRB 110518A
  6. GRB 110519A, Swift-BAT refined analysis
  7. GRB 110519A: Swift detection of a burst
  8. GRB 110426A: Fermi GBM detection
  9. GRB 110428A: Fermi-GBM observation
  10. GRB 110503A: TAROT Calern observatory optical observations
  11. Konus-Wind observation of GRB 110503A
  12. GRB 110503A: optical observation in CrAO
  13. GRB 110503A: Centimeter observation from EVLA
  14. GRB 110503A: Millimeter observation from SMA
  15. GRB 110503A: SARA-N Observations and Photometric Calibration
  16. GRB 110503A: Swift/UVOT Observations
  17. GRB 110503A: Swift-XRT refined Analysis
  18. GRB 110503A: PAIRITEL NIR Detection
  19. GRB 110503A: Swift-BAT refined analysis
  20. GRB 110503A: Enhanced Swift-XRT position
  21. GRB 110503A: Swift detection of a burst with a bright optical counterpart
  22. GRB 110426A: Swift/XRT non-detection
  23. GRB 110428A : X-ray afterglow confirmation
  24. GRB 110428A: Suzaku WAM observation of the prompt emission
  25. GRB 110422A: optical observations in CrAO
  26. GRB 110428A : Swift-XRT observations
  27. GRB 110426A: MASTER synchronous with MAXI/GSC observations
  28. GRB 110422A: optical observations in CrAO, second epoch
  29. GRB 110422A: Suzaku WAM observation of the prompt emission
  30. GRB110422A: NOT optical follow-ups
  31. GRB 110422A: optical observations in CrAO
  32. GRB110422A: MITSuME Ishigakijima Optical Observation
  33. GRB 110422A: Further NOT observation
  34. GRB 110422A: Swift/UVOT Detection of optical afterglow
  35. GRB 110422A: Swift-XRT refined Analysis
  36. GRB 110422A: Enhanced Swift-XRT position
  37. GRB 110422A: TNG optical observations
  38. GRB 110422A: SAO RAS optical observations
  39. GRB 110422A: NOT optical observation
  40. GRB 110422A: Swift-BAT refined analysis
  41. GRB 110422A: Mondy optical observations
  42. GRB 110422A: Swift detection of a burst
  43. GRB 110420B: Swift/UVOT Upper Limits
  44. GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
  45. GRB 110420B: Swift-XRT afterglow candidate retraction
  46. GRB 110420B, GROND observations
  47. GRB 110420A Swift/UVOT Observations
  48. GRB 110420B: Swift-XRT afterglow candidate
  49. GRB 110420B: Swift-BAT refined analysis
  50. GRB 110420A: Swift-BAT refined analysis
  51. GRB 110420A: Swift-XRT refined Analysis
  52. GRB 110420A: Enhanced Swift-XRT position
  53. GRB 110420A: Swift detection of a burst with optical counterpart
  54. GRB110414A: MITSuME Ishigakijima Optical upper limits
  55. GRB 110414A: GROND upper limits
  56. GRB110414A: MITSuME Okayama Optical upper limits
  57. GRB 110414A: Swift-BAT Refined Analysis
  58. GRB 110414A: Swift/UVOT Upper limits
  59. GRB 110414A: Swift-XRT refined Analysis
  60. GRB 110414A: Enhanced Swift-XRT position
  61. GRB 110328A / Swift J164449.3+573451: WISE quiescent source upper limit
  62. GRB 110414A : Faulkes Telescope North observations
  63. GRB 110414A: Swift detection of a burst
  64. GRB 110411A: PAIRITEL NIR Upper Limits
  65. GRB 110412A: Swift-BAT refined analysis
  66. GRB 110411A: Swift-XRT refined Analysis
  67. GRB 110411A: Swift/UVOT Upper Limits
  68. GRB 110411A : Xinglong TNT OT candidate
  69. GRB 110411A, Swift-BAT refined analysis
  70. GRB 110411A: Enhanced Swift-XRT position
  71. GRB 110411A: Swift detection of a burst
  72. GRB 110407A: Swift-XRT refined Analysis
  73. GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
  74. GRB 110328A / Swift J164449.3+573451: optical observations
  75. GRB 110328A/Swift J164449.3+573451 UVOT Upper Limits
  76. GRB 110406A: Positional coincidence with NGC 404
  77. GRB110407A: UVOT Upper Limits
  78. GRB 110407A: GROND Detection of the Optical Afterglow
  79. GRB 110407A: MITSuME Okayama and Ishigakijima Optical upper limits
  80. GRB 110407A: NOT optical observations
  81. GRB 110407A: Enhanced Swift-XRT position
  82. GRB 110407A: Swift-BAT refined analysis
  83. GRB 100407A : Errata of afterglow position in GCN 11899
  84. IPN triangulation of the bright GRB110406A
  85. GRB 110407A : Lulin optical afterglow detection
  86. GRB 110407A: Swift detection of a burst
  87. Konus-Wind observation of GRB 110406A
  88. GRB 110328A/Swift J164449.3+573451: BAT recent rate increase and pre-outburst,light curve
  89. GRB 110402A: fading optical afterglow
  90. GRB 110402A: Suzaku WAM observation of the prompt emission
  91. GRB 110402A: LOAO Optical Observation
  92. GRB 110328A / Swift J164449.3+573451, HST Observations
  93. GRB 110402A: Konus-Wind spectral lags and detailed energetics
  94. GRB 110401A: Fermi GBM detection
  95. GRB 110402A: Fermi GBM detection
  96. GRB 110402A: optical observations in Mondy
  97. GRB 110402A afterglow observation
  98. GRB 110328A / Swift J164449.3+573451: Keck/DEIMOS Optical Spectroscopy
  99. GRB 110402A: MITSuME Okayama and Ishigakijima Optical upper limits
  100. GRB 110328A/Swift J164449.3+573451: SARA-N detection

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