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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"

28126 results found.

  1. Swift trigger 456780 is not a burst
  2. GRB 110705A: Fermi GBM detection
  3. Swift Trigger 456659 is probably not astrophysical
  4. Swift-BAT trigger 456532 is not astrophysical
  5. SGR 1E 1841-045: early optical limit by "Pi of the Sky"
  6. SGR 1E 1841-045: Swift-BAT refined analysis
  7. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  8. GRB 110625A: Suzaku WAM observation of the prompt emission
  9. Swift J185003.2-005627: 1.23m CAHA and BOOTES-3 observations
  10. GRB 110625A: Fermi GBM and LAT observations
  11. GRB 110625A: Swift/UVOT Upper Limits
  12. GRB 110625A: 1.23m CAHA I-band observations
  13. GRB 110625A: Fermi LAT detection
  14. GRB 110625A: GROND detection of a source inside the XRT error circle
  15. GRB 110625A: Konkoly observations
  16. GRB 110625A: Swift-XRT refined Analysis
  17. GRB 110625A: Swift-BAT refined analysis
  18. Swift J185003.2-005627: NIR Observation
  19. GRB 110625A: Swift detection of a burst
  20. Swift J185003.2-005627: Swift-XRT/UVOT refined analysis
  21. Swift J185003.2-005627: Swift-BAT refined analysis
  22. Swift J185003.2-005627: TAROT La Silla observatory optical observations
  23. Swift J185003.2-005627: TAROT Calern observatory optical observations
  24. Swift J185003.2-005627: Swift detection of a burst from a new Galactic transient
  25. SGR 1E 1841-045: Swift-BAT refined analysis
  26. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  27. IPN triangulation of GRB110618A (long duration, extremely intense)
  28. GRB 110604A: Suzaku WAM observation of the prompt emission
  29. GRB 110610A: Suzaku WAM observation of the prompt emission
  30. GRB 110610A: Fermi GBM detection
  31. GRB 110610A: 1.23m CAHA optical observations
  32. GRB 110610A: Swift-XRT refined Analysis
  33. GRB 110610A: Swift/UVOT Upper Limits
  34. GRB 110610A: Enhanced Swift-XRT position
  35. GRB 110610A: Swift-BAT refined analysis
  36. Swift detection of the X-ray afterglow of GRB 110604A
  37. GRB 110610A: Swift detection of a burst
  38. GRB 110604A Detection by IPN Spacecraft and Swift-BAT
  39. GRB 110529A: Suzaku WAM observation of the prompt emission
  40. GMRT detection of GRB 110328A
  41. GRB 110530A: Swift-XRT refined Analysis
  42. GRB 110530A: Swift/UVOT Detection of a Fading Afterglow
  43. GRB 110530A: Enhanced Swift-XRT position
  44. GRB 110530A: NOT optical observations
  45. GRB110530A: MITSuME Okayama Optical Observation
  46. GRB 110530A: Swift-BAT refined analysis
  47. GRB 110529A: Fermi GBM detection
  48. GRB 110530A: Swift detection of a burst with an optical afterglow
  49. LAT Observations of GRB110529A
  50. EVLA afterglow limits on the high z GRB090429B
  51. Swift J1644+57/GRB 110328A, Additional HST Observations
  52. GRB 110521A: MASTER prompt optical limit
  53. GRB 110521A: Swift/UVOT Upper Limits
  54. GRB 110521A: Swift-XRT refined analysis
  55. GRB 110520A: NOT optical follow-ups
  56. GRB 110521A - NOT optical observation
  57. GRB 110521A: Swift-BAT refined analysis
  58. GRB 110521A: Enhanced Swift-XRT position
  59. GRB 110521A: MASTER synchronous and early optical observations limit
  60. Swift/UVOT observations of GRB110520A
  61. GRB 110521A: Swift detection of a burst
  62. GRB 110520A: Swift-BAT refined analysis
  63. GRB 110520A: IAC80 I-band observations
  64. GRB 110520A: Swift-XRT refined Analysis
  65. GRB 110520A: Enhanced Swift-XRT position
  66. GRB 110520A: WHT IR observations
  67. GRB 110520A - NOT optical observation
  68. GRB 110520A: TAROT Calern observatory optical observations
  69. GRB 110520A: Swift detection of a burst
  70. IPN localization of bright GRB 110518A
  71. GRB 110519A, Swift-BAT refined analysis
  72. GRB 110519A: Swift detection of a burst
  73. GRB 110426A: Fermi GBM detection
  74. GRB 110428A: Fermi-GBM observation
  75. GRB 110503A: TAROT Calern observatory optical observations
  76. Konus-Wind observation of GRB 110503A
  77. GRB 110503A: optical observation in CrAO
  78. GRB 110503A: Centimeter observation from EVLA
  79. GRB 110503A: Millimeter observation from SMA
  80. GRB 110503A: SARA-N Observations and Photometric Calibration
  81. GRB 110503A: Swift/UVOT Observations
  82. GRB 110503A: Swift-XRT refined Analysis
  83. GRB 110503A: PAIRITEL NIR Detection
  84. GRB 110503A: Swift-BAT refined analysis
  85. GRB 110503A: Enhanced Swift-XRT position
  86. GRB 110503A: Swift detection of a burst with a bright optical counterpart
  87. GRB 110426A: Swift/XRT non-detection
  88. GRB 110428A : X-ray afterglow confirmation
  89. GRB 110428A: Suzaku WAM observation of the prompt emission
  90. GRB 110422A: optical observations in CrAO
  91. GRB 110428A : Swift-XRT observations
  92. GRB 110426A: MASTER synchronous with MAXI/GSC observations
  93. GRB 110422A: optical observations in CrAO, second epoch
  94. GRB 110422A: Suzaku WAM observation of the prompt emission
  95. GRB110422A: NOT optical follow-ups
  96. GRB 110422A: optical observations in CrAO
  97. GRB110422A: MITSuME Ishigakijima Optical Observation
  98. GRB 110422A: Further NOT observation
  99. GRB 110422A: Swift/UVOT Detection of optical afterglow
  100. GRB 110422A: Swift-XRT refined Analysis

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