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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"

31730 results found.

  1. GRB060927: optical observations
  2. test of new software, grb
  3. GRB 060926: Swift-UVOT UVW1 Detection Retraction
  4. GRB 060927: Swift/UVOT Optical Observations
  5. GRB 060927: Early color
  6. GRB 060927: Swift XRT Team refined analysis
  7. GRB 060927 optical limit
  8. GRB 060927, Swift-BAT refined analysis
  9. GRB060926: improved redshift
  10. GRB 060927, optical observation
  11. GRB 060927: Possible host galaxy (star?) in the SDSS
  12. GRB060927: Faulkes Telescope South observation
  13. GRB 060926: MASTER: first minutes decay
  14. GRB 060927: optical afterglow confirmation
  15. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  16. GRB060926: VLT redshift
  17. GRB 060926: Swift-UVOT Detections
  18. GRB 060923A: Schedule of Spitzer Space Telescope Observations
  19. GRB 060926: OPTIMA-Burst -- further observations
  20. GRB 060926: Swift XRT refined analysis
  21. GRB 060926, Swift-BAT refined analysis
  22. GRB 060923A: Radio Observations
  23. GRB 060926: MASTER OT alert observation
  24. GRB 060912A: Redshift of probable host galaxy
  25. GRB 060926: BOOTES-IR observations
  26. GRB060926 OPTIMA-Burst optical observation
  27. GRB 060926: MASTER optical observation
  28. GRB 060923C, Swift-BAT refined analysis
  29. GRB 060923C: VLA Observation
  30. GRB 060923C: NIR afterglow confirmed
  31. GRB060923C: AROMA optical obsevation
  32. GRB 060923C: Gemini Observations and Afterglow Candidate
  33. GRB 060923C, optical observation
  34. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  35. GRB 060923C: VLT J-band observations
  36. GRB060923B: Swift/UVOT upper limits
  37. GRB 060923B: Swift XRT Refined Analysis
  38. GRB 060923C: Swift XRT refined analysis
  39. GRB 060923C, Swift-BAT partial refined analysis
  40. GRB 060923A: Swift XRT refined analysis
  41. GRB 060923C: Keck Observations
  42. GRB 060923A: Keck and Gemini Observations
  43. GRB 060923B, Swift-BAT refined analysis
  44. GRB060923C : Faulkes Telescope South optical limits
  45. GRB060923C: Faulkes Telescope North optical observations
  46. GRB 060923C: optical observation
  47. GRB 060923, Swift-BAT refined analysis
  48. GRB 060923: Early Super-LOTIS Observations
  49. GRB 060923: UKIRT nIR observations - candidate afterglow
  50. GRB060923: Faulkes Telescope North optical observations
  51. GRB060923 - SDSS Pre-Burst Observations
  52. GRB 060923: KAIT observations
  53. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  54. GRB060919: Swift/UVOT optical observations
  55. GRB 060919 : Faulkes South Telescope Observations
  56. GRB 060919, Swift-BAT refined analysis
  57. GRB060919: XRT refined analysis
  58. GRB 060912A: VLA Observation
  59. GRB 060912A: Probable Host Galaxy
  60. GRB060825: MAGIC telescope GeV observation
  61. Konus-Wind observation of GRB 060912
  62. GRB 060912: Redshift of nearby 2MASS galaxy
  63. GRB060912: optical observations
  64. GRB060912: Swift/UVOT Observations
  65. GRB060912: OPTIMA-Burst optical observations
  66. GRB 060912: Swift XRT Team Refined Analysis
  67. GRB 060912, Swift-BAT refined analysis
  68. GRB 060912: Correction to GCN 5559
  69. VLA observations of GRB 060908
  70. GRB 060908: redshift
  71. GRB 060908, Swift/XRT refined analysis
  72. GRB 060908: Swift/UVOT Observations
  73. GRB 060908: Danish/DFOSC optical observations
  74. GRB 060908, Swift-BAT refined analysis
  75. GRB 060904B : CFHT/WIRCam NIR afterglow observations
  76. GRB 060908: REM optical prompt observation
  77. GRB 060904A: Suzaku/WAM observation of the prompt emission
  78. GRB060906 , optical observation
  79. GRB060904b optical detections (delayed report due to internet outage)
  80. GRB 060906: optical observation
  81. GRB 060906: Early RAPTOR optical limits
  82. GRB 060906, Swift-BAT refined spectral analysis
  83. GRB 060906: Swift/XRT Refined Analysis
  84. GRB 060906: Swift-UVOT observations
  85. VLT redshift of GRB 060906
  86. GRB 060906, Swift-BAT refined analysis
  87. GRB 060906: FRAM observations - flash determination (airplane)
  88. GRB 060906: KAIT observations
  89. GRB 060906: Confirmation of P60 Optical Afterglow
  90. GRB 060906: observations with FRAM
  91. GRB 060904A Milagro GeV/TeV Observations
  92. GRB060904b, optical observations
  93. GRB 060904b: SMARTS optical/IR afterglow observations
  94. GRB 060904B: RTT150 optical observations
  95. GRB060904A: Swift/UVOT optical observations
  96. GRB 060904A: Subaru NIR observation
  97. GRB 060904A: pseudo-z from spectral parameters of the prompt emission
  98. GRB 060904B: Swift-BAT refined analysis
  99. GRB060904b: Optical observations with Swift/UVOT
  100. Konus-Wind observation of GRB 060904A

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