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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"
  1. GRB 140703A: AMI 15 GHz detection
  2. GRB 140705A / SGR 1935+2154: VLA 6 GHz observations
  3. GRB 140706A: Swift/UVOT Detection
  4. GRB 140703A: Swift/UVOT Upper Limits
  5. GRB 140706A: Swift-BAT refined analysis
  6. GRB 140706A: Swift-XRT refined Analysis
  7. GRB 140706A: Fermi GBM detection
  8. GRB 140703A: AAO optical observations
  9. Pre-discovery observations of SGR 1935+2154 in Swift archival data
  10. GRB140706A: GROND detection of the Optical/NIR afterglow
  11. GRB 140705A / SGR 1935+2154: Probable association with supernova remnant G57.2+0.8
  12. GRB 140706A: Enhanced Swift-XRT position
  13. GRB 140706A: Swift detection of a burst with an optical counterpart
  14. SGR 1935+2154: Swift-BAT observations of additional short soft events
  15. GRB 140705A / SGR 1935+2154: FTN observations
  16. GRB 140705A / SGR 1935+2154: Optical observations from 10.4m GTC
  17. GRB 140705A: KAIT Optical Upper Limit
  18. GRB 140705A: MITSuME Ishigakijima upper limits
  19. GRB 140705A: Swift-XRT refined Analysis
  20. GRB 140705A: MITSuME Okayama upper limits
  21. GRB 140705A: Swift/UVOT Upper Limits
  22. GRB 140705A: Swift-BAT refined analysis of a possible newly discovered SGR 1935+2154
  23. GRB 140705A: Enhanced Swift-XRT position
  24. GRB 140705A: Swift detection of a short burst
  25. GRB 140621A: Suzaku WAM observation of the prompt emission
  26. GRB 140629A: SAO RAS Rc band photometry
  27. GRB 140629A, Optical observations
  28. GRB 140703A: VLA K-band detection
  29. GRB 140703A: CARMA 3mm detection
  30. GRB 140703A: P60 observations of a red, slowly-fading afterglow
  31. GRB 140703A: RATIR Optical and NIR Observations
  32. GRB 140703A: Fermi GBM detection
  33. GRB 140703A: Monte Agliale Observatory optical observations
  34. GRB 140703A: Swift-XRT refined Analysis
  35. GRB 140703A: Swift-BAT refined analysis
  36. Correction to GCN 16507: GRB 140703A!
  37. GRB 140703A: MASTER optical observations
  38. GRB 140703A: Enhanced Swift-XRT position
  39. GRB140703A: 10.4m GTC redshift
  40. GRB 140703A: BOOTES-2 and OSN optical observations
  41. GRB 140703A: Swift detection of a burst
  42. GRB 140619C: Suzaku WAM observation of the prompt emission
  43. GRB 140629A: MITSuME Akeno Optical observation
  44. GRB 140629A: MASTER-Net preliminary light curve
  45. GRB 140629A: SAO RAS monitoring
  46. GRB 140629A: additional P60 observations
  47. Fermi 425667201: optical counterpart search
  48. GRB 140629A: Nishi-Harima NIR Observations
  49. Konus-Wind observation of GRB 140629A
  50. GRB 140629A: Swift/UVOT Detection
  51. GRB 140629A: TNG redshift confirmation
  52. GRB140629A: VATT optical observations
  53. GRB 140629A: P60 observations
  54. GRB 140629A: Swift-XRT refined Analysis
  55. GRB 140629A: BTA redshift
  56. GRB 140629A: MITSuME Ishigakijima Optical Observation
  57. GRB140629A: Kanata/HOWPol optical observation
  58. GRB 140629A: T100 observations
  59. GRB 140629A: NOT optical observations
  60. GRB 140629A: KWFC z-band photometry
  61. GRB 140629A : Virtual Telescope optical observations
  62. GRB 140629A: RTT150 optical observations
  63. GRB 140629A: Swift-BAT refined analysis
  64. GRB 140629A : Xinglong TNT optical observation
  65. GRB 140629A: Enhanced Swift-XRT position
  66. GRB 140629A: MASTER OT detection
  67. GRB 140629A: Swift detection of a burst with an optical counterpart
  68. GRB 140628A: GROND observation of the afterglow
  69. GRB 140628A: Swift-XRT refined Analysis
  70. GRB 140628A: Zadko observatory - Gingin optical observations
  71. GRB 140628A: Swift-BAT refined analysis
  72. GRB 140628A: Swift/UVOT Detection
  73. GRB 140628A: Swift/UVOT Detection
  74. GRB 140628A: Swift-XRT afterglow detection and enhanced position
  75. GRB 140626A: TAROT La Silla observatory optical observations
  76. GRB 140622A: TAROT La Silla observatory optical observations
  77. GRB 140628A: Swift detection of a burst
  78. GRB 140619B: Magellan near-infrared observations
  79. Swift Trigger 602668: XRT and UVOT confirm is not astrophysical source
  80. GRB 140623A: further Swift-XRT observations
  81. Swift Trigger 602668 is probably not an astrophysical source
  82. GRB 140626A: Swift-BAT refined analysis
  83. GRB 140626A: Swift-XRT refined Analysis
  84. GRB 140626A: Swift/UVOT Upper Limits
  85. GRB 140626A: Enhanced Swift-XRT position
  86. GRB 140626A: GROND Afterglow Candidate
  87. GRB 140619B: Suzaku WAM observation of the prompt emission
  88. GRB 140626A: Swift detection of a burst
  89. Further Swift/XRT observations of GRB140620A/iPTFcva
  90. GRB140606B/iPTF14bfu: Keck detection of an associated supernova
  91. GRB 140620A / iPTF14cva: TShAO optical observations
  92. GRB 140624A: Fermi GBM observation of a short burst
  93. GRB 140623A: Swift-XRT and UVOT observations
  94. GRB 140623A / iPTF14cyb: Fermi GBM detection
  95. GRB 140621A: Swift-XRT observations
  96. GRB 140622A: iTelescope.Net T11 Optical Observation
  97. GRB 140621A: Fermi GBM detection
  98. GRB 140622A: Swift/UVOT Upper Limits
  99. Konus-Wind observation of GRB 140621A
  100. IPN Triangulation of GRB 140621A

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