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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"

25007 results found.

  1. GRB060923C: AROMA optical obsevation
  2. GRB 060923C, optical observation
  3. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  4. GRB 060923C: VLT J-band observations
  5. GRB 060923B: Swift XRT Refined Analysis
  6. GRB 060923A: Swift XRT refined analysis
  7. GRB 060923A: Keck and Gemini Observations
  8. GRB 060923C: Xinglong TNT optical observations
  9. GRB 060923B, Swift-BAT refined analysis
  10. GRB 060923C: Swift detection of a burst
  11. GRB 060923B: Swift detection of a burst
  12. GRB 060923, Swift-BAT refined analysis
  13. GRB 060923: UKIRT nIR observations - candidate afterglow
  14. GRB060923 - SDSS Pre-Burst Observations
  15. GRB 060923: Swift detection of a burst
  16. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  17. GRB 060919 : Faulkes South Telescope Observations
  18. GRB 060919, Swift-BAT refined analysis
  19. GRB060919: XRT refined analysis
  20. GRB 060919: TAROT optical observations
  21. GRB 060919: Swift detection of a burst
  22. GRB 060912A: VLA Observation
  23. GRB 060912A: Probable Host Galaxy
  24. GRB 060912, Swift-BAT refined analysis
  25. GRB 060912: Correction to GCN 5559
  26. GRB 060912: Swift detection of a burst with an optical afterglow
  27. VLA observations of GRB 060908
  28. GRB 060908, Swift-BAT refined analysis
  29. GRB 060908 - SDSS Pre-burst Observations
  30. GRB 060908: REM optical prompt observation
  31. GRB 060908: Swift detection of a burst with a bright optical counterpart
  32. GRB 060904A: Suzaku/WAM observation of the prompt emission
  33. GRB060906 , optical observation
  34. GRB 060906: Early RAPTOR optical limits
  35. GRB 060906, Swift-BAT refined spectral analysis
  36. GRB 060906: Swift/XRT Refined Analysis
  37. VLT redshift of GRB 060906
  38. GRB 060906, Swift-BAT refined analysis
  39. GRB 060906: Confirmation of P60 Optical Afterglow
  40. GRB 060906 (?): P60 Optical Afterglow Candidate
  41. GRB060904b, optical observations
  42. GRB060904A: Swift/UVOT optical observations
  43. GRB 060904A: Subaru NIR observation
  44. GRB 060904B: Swift-BAT refined analysis
  45. GRB 060904A: Refined analysis of the Swift-BAT burst
  46. GRB 060904A: Suzaku-XIS and -HXD observation plan
  47. GRB 060904A: P60 Observations
  48. GRB 060904B: Optical observations at Crni Vrh
  49. GRB 060904B: TAROT optical counterpart observations
  50. GRB060904B - SDSS Pre-Burst Observations
  51. GRB 060904: TAROT optical observations
  52. GRB 060904B: Swift detection of a burst with optical counterpart
  53. GRB060904 - SDSS Pre-Burst Observations
  54. GRB 060904: Swift detection of a bright burst
  55. GRB060901: Optical observations
  56. 060901: Swift UVOT followup observations
  57. GRB 060901: Swift/XRT Refined Analysis
  58. GRB 060901: Swift/XRT Position
  59. GRB 060901: a long GRB detected by INTEGRAL
  60. Two bright bursts from SGR 1806-20 detected with IBAS
  61. GRB 060605, observations using an Integral Field Unit
  62. GRB 060604: VLA Observation
  63. GRB 060814: Suzaku/WAM observation of the prompt emission
  64. GRB 060605: VLA Observation
  65. GRB 060707: VLA observation
  66. GRB 060825: VLA observations
  67. GRB060826 - SDSS Pre-Burst Observations
  68. GRB 060826(?): Swift detection of a possible burst
  69. GRB 060825: XRT Team Refined Analysis
  70. GRB 060825: Swift-BAT Refined Analysis
  71. GRB 060813: Swift/BAT, Konus-Wind, and Suzaku/WAM joint prompt spectral analysis
  72. GRB 060825: TNG optical observations
  73. GRB 060825: TAROT optical observations
  74. GRB 060825: P60 Observations
  75. GRB 060825: Swift detection of a burst
  76. GRB060801: host galaxy redshift
  77. GRB060729: analysis of XMM-Newton observation
  78. GRB 060729, SMARTS optical/IR observations
  79. GRB 060813: A long, bright GRB detected with Suzaku WAM
  80. Konus-Wind observation of GRB 060814
  81. GRB 060814: Refined analysis of the Swift-BAT burst
  82. GRB 060814: P60 Observations
  83. GRB 060814: P200 NIR Observations
  84. GRB060805B: optical observations
  85. GRB 060814: Swift XRT refined analysis
  86. GRB 060814: VLT optical limits
  87. GRB 060814 - SDSS Pre-Burst Observations
  88. GRB 060814: TAROT optical observations
  89. GRB 060814: Swift detection of a bright burst
  90. Konus-Wind observation of GRB 060813
  91. GRB 060813: Swift XRT refined analysis
  92. GRB 060813: Refined analysis of the Swift-BAT burst
  93. GRB 060813: Swift detection of a burst
  94. GRB051109B: Late-time Radio Observations
  95. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  96. GRB060807: Possible Highly Significant X-ray Emission Lines
  97. GRB 060729: An update on the Swift XRT and UVOT observations
  98. GRB060717: optical observations
  99. GRB060807: Optical limiting magnitudes
  100. GRB 060805B: XRT Team Analysis

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