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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"
  1. GRB 110709A: Enhanced Swift-XRT position
  2. GRB 110709B: Swift detection of a burst
  3. GRB 110708A: Swift/UVOT Observations
  4. GRB 110709A: MASTER-NET optical observations
  5. GRB 110709A: Prompt enhanced Swift-XRT position
  6. GRB 110709A: Swift detection of a burst
  7. GRB 110708A: Liverpool Telescope observations
  8. GRB 110708A: Lick observations
  9. GRB 110708A: Swift/XRT afterglow candidate for the INTEGRAL burst
  10. GRB 110705A: Suzaku WAM observation of the prompt emission
  11. GRB 110625A, the review of the sky area in plate archives
  12. GRB 110708A: a long GRB detected by INTEGRAL
  13. Konus-Wind observation of GRB 110705A
  14. IPN triangulation of short hard GRB 110705A
  15. Swift trigger 456780 is not a burst
  16. GRB 110705A: Fermi GBM detection
  17. Swift Trigger 456659 is probably not astrophysical
  18. Swift-BAT trigger 456532 is not astrophysical
  19. SGR 1E 1841-045: early optical limit by "Pi of the Sky"
  20. SGR 1E 1841-045: Swift-BAT refined analysis
  21. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  22. GRB 110625A: Suzaku WAM observation of the prompt emission
  23. Swift J185003.2-005627: 1.23m CAHA and BOOTES-3 observations
  24. GRB 110625A: Fermi GBM and LAT observations
  25. GRB 110625A: Swift/UVOT Upper Limits
  26. GRB 110625A: 1.23m CAHA I-band observations
  27. GRB 110625A: Fermi LAT detection
  28. GRB 110625A: GROND detection of a source inside the XRT error circle
  29. GRB 110625A: NIR Source
  30. GRB 110625A: Konkoly observations
  31. Konus-Wind observation of GRB 110625A
  32. GRB 110625A: Swift-XRT refined Analysis
  33. GRB 110625A: Swift-BAT refined analysis
  34. Swift J185003.2-005627: NIR Observation
  35. GRB 110625A: ROTSE-III Optical Limits
  36. GRB 110625A: Swift detection of a burst
  37. Swift J185003.2-005627: Swift-XRT/UVOT refined analysis
  38. Swift J185003.2-005627: Swift-BAT refined analysis
  39. Swift J185003.2-005627: TAROT La Silla observatory optical observations
  40. Swift J185003.2-005627: TAROT Calern observatory optical observations
  41. Swift J185003.2-005627: Swift detection of a burst from a new Galactic transient
  42. SGR 1E 1841-045: Swift-BAT refined analysis
  43. GRB 110618A: SMARTS optical observations
  44. GRB 110604A: final update on Swift-XRT observations
  45. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  46. Konus-Wind observation of GRB 110618A
  47. IPN triangulation of GRB110618A (long duration, extremely intense)
  48. Fermi Gamma-ray Burst Monitor trigger 110621949 is not a GRB
  49. GRB 110604A: Suzaku WAM observation of the prompt emission
  50. GRB 110610A: Suzaku WAM observation of the prompt emission
  51. GRB 110610A: Fermi GBM detection
  52. GRB 110610A: 1.23m CAHA optical observations
  53. GRB 110610A: Swift-XRT refined Analysis
  54. GRB 110610A: Swift/UVOT Upper Limits
  55. GRB 110610A: Enhanced Swift-XRT position
  56. GRB 110610A: Swift-BAT refined analysis
  57. Swift detection of the X-ray afterglow of GRB 110604A
  58. GRB 110610A: MASTER-NET optical observations
  59. GRB 110610A: Swift detection of a burst
  60. Konus-Wind observation of GRB 110604A
  61. GRB 110604A Detection by IPN Spacecraft and Swift-BAT
  62. GRB 110530A: optical observations in Mondy observatory
  63. GRB 110529A: Suzaku WAM observation of the prompt emission
  64. GMRT detection of GRB 110328A
  65. GRB 110530A: optical observations at Mt. Terskol, second epoch
  66. GRB 110530A: Swift-XRT refined Analysis
  67. GRB 110530A: Swift/UVOT Detection of a Fading Afterglow
  68. GRB 110530A: Xinglong TNT observation
  69. GRB 110530A: Enhanced Swift-XRT position
  70. GRB 110530A: NOT optical observations
  71. GRB110530A: MITSuME Okayama Optical Observation
  72. GRB 110530A: optical observations at Mt. Terskol
  73. GRB 110530A: Correction to GCN Circ 12050
  74. GRB 110530A: MASTER OT observations
  75. GRB 110530A: Swift-BAT refined analysis
  76. GRB 110530A: MITSuME Akeno Optical Observation
  77. GRB 110529A: Fermi GBM detection
  78. GRB 110530A: Swift detection of a burst with an optical afterglow
  79. Konus-Wind observation of GRB 110529A
  80. LAT Observations of GRB110529A
  81. EVLA afterglow limits on the high z GRB090429B
  82. Fermi Gamma-ray Burst Monitor trigger 328195911 is not a GRB
  83. Swift J1644+57/GRB 110328A, Additional HST Observations
  84. GRB 110521A: MASTER prompt optical limit
  85. GRB 110521A: Swift/UVOT Upper Limits
  86. GRB 110521A: Swift-XRT refined analysis
  87. GRB 110520A: NOT optical follow-ups
  88. GRB 110521A - NOT optical observation
  89. GRB 110521A: Swift-BAT refined analysis
  90. GRB 110521A: Enhanced Swift-XRT position
  91. GRB 110521A: MASTER synchronous and early optical observations limit
  92. Swift/UVOT observations of GRB110520A
  93. GRB 110521A: Swift detection of a burst
  94. GRB 110520A: Swift-BAT refined analysis
  95. GRB 110520A: IAC80 I-band observations
  96. GRB 110520A: Swift-XRT refined Analysis
  97. GRB 110520A: Enhanced Swift-XRT position
  98. GRB 110520A: WHT IR observations
  99. GRB 110520A - NOT optical observation
  100. GRB 110520A: Skynet/DAO optical observations

Advanced

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