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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"

19533 results found.

  1. The Swift-XRT source associated with trigger 518853 is a cosmic ray
  2. Trigger 518853: Swift detection of a probable Galactic transient
  3. GRB 120327A: Zadko optical observations
  4. GRB 120328A: Swift/UVOT Upper Limits
  5. GRB 120328A: Swift-XRT refined Analysis
  6. IPN Triangulation of GRB 120328B (long/intense)
  7. GRB 120328A: Swift-BAT refined analysis
  8. GRB 120328A: Enhanced Swift-XRT position
  9. GRB 120328A: TAROT La Silla observatory optical observations
  10. Skynet/PROMPT observations of GRB120328A
  11. GRB 120328A: Swift detection of a burst
  12. GRB 120326A: Fermi GBM Observation
  13. GRB 120327A afterglow detection
  14. GRB 120326A: PAIRITEL NIR Observations
  15. GRB 120326A: Bassano Bresciano Observatory optical observations
  16. GRB 120327A: Swift-XRT refined Analysis
  17. GRB 120327A: Swift/UVOT further analysis
  18. GRB 120327A: Swift-BAT refined analysis
  19. GRB 120327A: Enhanced Swift-XRT position
  20. GRB 120327A: X-shooter redshift
  21. GROND observations of GRB 120327A
  22. GRB 120327A: Liverpool Telescope Observations
  23. GRB 120327A: TAROT La Silla observatory optical detection
  24. GRB 120327A: Swift detection of a burst with an optical counterpart
  25. GRB 120326A: Swift-BAT refined analysis
  26. GRB 120326A: Swift-XRT refined Analysis
  27. GRB 120326A: Swift/UVOT Detection
  28. GRB 120326A: Optical observations at Crni Vrh
  29. GRB120326A: IAC80 observations
  30. GRB 120326A: Liverpool Telescope observations
  31. GRB 120326A: Enhanced Swift-XRT position
  32. Skynet/Dolomiti Observations of GRB120326A
  33. GRB 120326A: TAROT Calern observatory afterglow optical detection
  34. GRB 120326A: ROTSE-III Optical Limits
  35. GRB 120326A: Swift detection of a burst
  36. IPN Triangulation of GRB 120323A (short/very intense)
  37. GRB 120324A: Swift-XRT refined Analysis
  38. Konus-Wind observation of GRB 120324A
  39. GRB 120324A: GROND observations
  40. GRB 120324A: Swift-BAT refined analysis
  41. GRB 120324A: Swift/UVOT Upper Limits
  42. GRB 120324A: TAROT La Silla observatory optical observations
  43. GRB 120324A: Enhanced Swift-XRT position
  44. GRB 120324A: Liverpool Telescope optical candidate
  45. GRB 120324A: UVOT Finding Chart Observation
  46. GRB 120324A: Swift detection of a burst
  47. Simultaneous optical images of Swift pointing are available by GRT
  48. GRB 120320A: Zadko optical observations
  49. GRB 120320A: Swift/UVOT Upper Limits
  50. GRB 120320A: BOOTES-4 optical upper limit
  51. GRB 120320A: Swift-XRT refined Analysis
  52. GRB 120320A, Swift-BAT refined analysis
  53. GRB 120320A: Enhanced Swift-XRT position
  54. IPN Triangulation of GRB 120316A
  55. GRB 120320A: MASTER optical observations
  56. GRB 120320A: Swift detection of a burst
  57. Trigger 517876 is a Swift detection of GX 5-1
  58. GRB 120302A: Swift XRT refined analysis
  59. GRB 120312A: CrAO optical upper limit
  60. GRB 120311A: Optical follow-up
  61. GRB 120311A: C88 optical limits
  62. GRB 120312A: Swift/UVOT Upper Limits
  63. GRB 120312A: MASTER-NET optical observations
  64. GRB 120312A: NOT observations
  65. GRB 120312A: Swift-XRT refined Analysis
  66. GRB 120312A: Swift-BAT refined analysis
  67. GRB 120311A: VLT/X-shooter observations
  68. GRB 120311B: C88 optical limits
  69. GRB 120312A: Swift detection of a burst
  70. GRB 120311B: Swift/UVOT Upper Limits
  71. GRB 120311B: Faulkes Telescope North observations
  72. GRB 120311B: Swift-XRT refined Analysis
  73. GRB 120311A: Swift-XRT refined Analysis
  74. GRB 120311B: Enhanced Swift-XRT position
  75. GRB 120311B: Swift-BAT refined analysis
  76. GRB 120311B: Swift-XRT observations
  77. GRB 120311A, Swift-BAT refined analysis
  78. GRB 120311B: Swift detection of a burst
  79. GRB 120311A: Swift/UVOT Upper Limits
  80. GRB 120311A: Enhanced Swift-XRT position
  81. GRB 120311A: Swift-XRT observations
  82. GRB 120311A: Liverpool Telescope optical candidate
  83. GRB 120311A: Swift detection of a burst
  84. GRB 120308A: 1.23m CAHA I-band observations
  85. GRB 120308A: Swift/UVOT Detection
  86. GRB 120308A: Swift-XRT refined Analysis
  87. GRB 120308A: Enhanced Swift-XRT position
  88. GRB 120308A: Swift-BAT refined analysis
  89. GRB 120308A: PAIRITEL NIR observations
  90. GRB 120308A: confirmation of the optical afterglow
  91. GRB 120308A: Liverpool Telescope optical afterglow candidate
  92. GRB 120308A: Swift detection of a burst
  93. GRB 120305A: D50 optical limits
  94. GRB 120305A: Swift spectral lag analysis
  95. GRB 120302A: Fermi GBM Observation
  96. GRB 120302A: Swift-BAT refined position and a possible XRT and UVOT counterpart
  97. GRB 120305A: Swift/UVOT Upper Limits
  98. GRB 120305A: Swift-XRT refined Analysis
  99. GRB 120305A: Enhanced Swift-XRT position
  100. GRB 120305A: Swift-BAT refined analysis

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