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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"

25030 results found.

  1. GRB 060929: TNG K-band observations
  2. GRB 060929, Swift-BAT refined analysis
  3. GRB060929: Optical limit
  4. Liverpool Telescope observations of GRB 060929
  5. GRB060908: optical observations
  6. GRB 060927: Swift/UVOT Optical Observations
  7. GRB 060927: Swift XRT Team refined analysis
  8. GRB 060927 optical limit
  9. GRB 060927, Swift-BAT refined analysis
  10. GRB 060927: Xinglong TNT optical observations
  11. GRB 060927, optical observation
  12. GRB060927 - SDSS Pre-Burst Observations
  13. Swift XRT boresight
  14. GRB060926: VLT redshift
  15. GRB 060926: Swift-UVOT Detections
  16. GRB 060923A: Schedule of Spitzer Space Telescope Observations
  17. GRB 060926, Swift-BAT refined analysis
  18. GRB 060923A: Radio Observations
  19. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  20. GRB 060926: Swift detection of a burst
  21. GRB 060923C, Swift-BAT refined analysis
  22. GRB 060923C: VLA Observation
  23. GRB 060923C: NIR afterglow confirmed
  24. GRB060923C: AROMA optical obsevation
  25. GRB 060923C, optical observation
  26. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  27. GRB 060923C: VLT J-band observations
  28. GRB 060923B: Swift XRT Refined Analysis
  29. GRB 060923A: Swift XRT refined analysis
  30. GRB 060923A: Keck and Gemini Observations
  31. GRB 060923C: Xinglong TNT optical observations
  32. GRB 060923B, Swift-BAT refined analysis
  33. GRB 060923C: Swift detection of a burst
  34. GRB 060923B: Swift detection of a burst
  35. GRB 060923, Swift-BAT refined analysis
  36. GRB 060923: UKIRT nIR observations - candidate afterglow
  37. GRB060923 - SDSS Pre-Burst Observations
  38. GRB 060923: Swift detection of a burst
  39. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  40. GRB 060919 : Faulkes South Telescope Observations
  41. GRB 060919, Swift-BAT refined analysis
  42. GRB060919: XRT refined analysis
  43. GRB 060919: TAROT optical observations
  44. GRB 060919: Swift detection of a burst
  45. GRB 060912A: VLA Observation
  46. GRB 060912A: Probable Host Galaxy
  47. GRB 060912, Swift-BAT refined analysis
  48. GRB 060912: Correction to GCN 5559
  49. GRB 060912: Swift detection of a burst with an optical afterglow
  50. VLA observations of GRB 060908
  51. GRB 060908, Swift-BAT refined analysis
  52. GRB 060908 - SDSS Pre-burst Observations
  53. GRB 060908: REM optical prompt observation
  54. GRB 060908: Swift detection of a burst with a bright optical counterpart
  55. GRB 060904A: Suzaku/WAM observation of the prompt emission
  56. GRB060906 , optical observation
  57. GRB 060906: Early RAPTOR optical limits
  58. GRB 060906, Swift-BAT refined spectral analysis
  59. GRB 060906: Swift/XRT Refined Analysis
  60. VLT redshift of GRB 060906
  61. GRB 060906, Swift-BAT refined analysis
  62. GRB 060906: Confirmation of P60 Optical Afterglow
  63. GRB 060906 (?): P60 Optical Afterglow Candidate
  64. GRB060904b, optical observations
  65. GRB060904A: Swift/UVOT optical observations
  66. GRB 060904A: Subaru NIR observation
  67. GRB 060904B: Swift-BAT refined analysis
  68. GRB 060904A: Refined analysis of the Swift-BAT burst
  69. GRB 060904A: Suzaku-XIS and -HXD observation plan
  70. GRB 060904A: P60 Observations
  71. GRB 060904B: Optical observations at Crni Vrh
  72. GRB 060904B: TAROT optical counterpart observations
  73. GRB060904B - SDSS Pre-Burst Observations
  74. GRB 060904: TAROT optical observations
  75. GRB 060904B: Swift detection of a burst with optical counterpart
  76. GRB060904 - SDSS Pre-Burst Observations
  77. GRB 060904: Swift detection of a bright burst
  78. GRB060901: Optical observations
  79. 060901: Swift UVOT followup observations
  80. GRB 060901: Swift/XRT Refined Analysis
  81. GRB 060901: Swift/XRT Position
  82. GRB 060901: a long GRB detected by INTEGRAL
  83. Two bright bursts from SGR 1806-20 detected with IBAS
  84. GRB 060605, observations using an Integral Field Unit
  85. GRB 060604: VLA Observation
  86. GRB 060814: Suzaku/WAM observation of the prompt emission
  87. GRB 060605: VLA Observation
  88. GRB 060707: VLA observation
  89. GRB 060825: VLA observations
  90. GRB060826 - SDSS Pre-Burst Observations
  91. GRB 060826(?): Swift detection of a possible burst
  92. GRB 060825: XRT Team Refined Analysis
  93. GRB 060825: Swift-BAT Refined Analysis
  94. GRB 060813: Swift/BAT, Konus-Wind, and Suzaku/WAM joint prompt spectral analysis
  95. GRB 060825: TNG optical observations
  96. GRB 060825: TAROT optical observations
  97. GRB 060825: P60 Observations
  98. GRB 060825: Swift detection of a burst
  99. GRB060801: host galaxy redshift
  100. GRB060729: analysis of XMM-Newton observation

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