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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"

21013 results found.

  1. Optical observations of GRB 071020
  2. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  3. GRB 071020: SARA observations
  4. Radio detection of GRB 071020 with the VLA
  5. GRB 071021: Subaru NIR observation
  6. GRB071021: MITSuME Okayama Optical Upper Limits
  7. GRB 071021: Magellan i-band observation
  8. GRB 071021: Magellan R-band observation
  9. GRB 071020: Fading slowly?
  10. GRB 071010B: Fading quickly
  11. GRB 071021: optical and NIR observations
  12. GRB 071021: possible high-z burst
  13. GRB 071021 : Lulin R-band limit
  14. GRB 071021: Faulkes Telescope South optical candidate
  15. GRB 071010B: Independent Confirmation of Break
  16. GRB071020A: Xinglong TNT Optical afterglow observations
  17. GRB 071020: Swift-XRT refined analysis
  18. GRB071020 - SDSS Pre-burst Observations
  19. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  20. GRB 071018: Mercator Telescope optical observations
  21. Swift autonomous slewing re-enabled
  22. GRB071010b: optical observations
  23. GRB 071018: SARA observations
  24. GRB 071018: Swift-XRT observation
  25. GRB 071017 - Swift XRT observations
  26. GRB 071018: Possible OT from Xinglong TNT observation
  27. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  28. GRB 071018?: Swift detection of a possible burst
  29. GRB071013: optical observations
  30. GRB 071010B: Optical observations of EST
  31. GRB 071011: MITSuME Optical Observations
  32. GRB 070920A: deep optical observations at the NOT
  33. GRB 071010B: Photometry after 1.6 days
  34. GRB 071010B: Keck/LRIS Photometry
  35. GRB 071010B: TLS 2nd Epoch, refined analysis
  36. GRB 071013: Optical observations
  37. GRB 071013: optical observations at NOT
  38. GRB071010B, BVRcIc field calibration
  39. GRB 071011: Xinglong TNT Optical afterglow observations
  40. GRB 071010B correction to GCN 6892 optical observations
  41. GRB 071011: Swift-XRT refined analysis
  42. GRB 071011: NAYUTA Optical Observation, correction to GCN6886
  43. GRB 071011, Optical afterglow
  44. GRB 071011: P60 Optical Afterglow Candidate
  45. GRB 071010B optical photometry
  46. GRB 071010B: Gemini Spectroscopic Observations
  47. GRB 071011: Early Super-LOTIS Observations
  48. GRB 071010A: Continued Keck Imaging
  49. GRB 071011: Optical afterglow candidate
  50. Optical Observation: GRB 071010
  51. Optical observations: GRB 071010A
  52. GRB 071010A: bright NIR afterglow
  53. GRB071008: optical observations
  54. GRB 071010B possible optical transient
  55. GRB 071010B: Swift detection of a burst
  56. GRB071008: Swift-XRT observation
  57. GRB 071010 REM NIR observations
  58. GRB 071010: TAROT La Silla observatory photometry of the afterglow
  59. GRB 071010: Keck Observations of the Afterglow
  60. GRB 071010: TAROT La Silla observatory detection of the afterglow
  61. GRB 071010: Swift detection of a burst
  62. GRB 071008: Swift detection of a burst
  63. GRB 071003: XRT refined analysis
  64. Radio detection of GRB 071003 with the VLA
  65. GRB 070810B: further XRT analysis
  66. GRB 071003: VLT spectroscopy
  67. GRB071003: Faulkes Telescope North observations
  68. GRB 071003: Possible rebrightening
  69. GRB 071003 : Lulin R-band observations
  70. GRB 071003: OA power-law decay indices from KAIT
  71. GRB 071003: Keck HIRES spectroscopy
  72. GRB 071003: MARGE Observations
  73. GRB 071003 Optical observations
  74. GRB 071003: P60 Confirmation of Optical Afterglow
  75. GRB 071003: KAIT optical afterglow observations
  76. GRB 071003: Swift detection of a bright burst
  77. GRB 070714B: host galaxy spectroscopic redshift
  78. GRB 071001: Swift-XRT Team refined analysis
  79. Faulkes Telescope South observations of GRB 071001
  80. GRB 070911, SMARTS optical/IR afterglow observations
  81. GRB070925: Swift-XRT Afterglow confirmation
  82. GRB070925: Swift-XRT Position
  83. Update on Swift Status
  84. Recent SGR1806-20 Activity
  85. GRB 070920B: XRT observations
  86. GRB 070923: Swift detection of a short hard burst
  87. GRB 070920B: TAROT La Silla observatory optical observations
  88. INTEGRAL ToO observations of SGR1806-20
  89. GRB 070917: Confirmation of the X-ray afterglow
  90. GRB 070920b: LCO optical observations
  91. GRB 070920B: NOT optical observations
  92. GRB 070920B: Swift detection of a burst
  93. GRB 070920: TAROT Calern observatory optical observations
  94. GRB 070920: Swift detection of a burst
  95. GRB070917: Confirmation of optical afterglow
  96. GRB070917: optical observations
  97. GRB 070917: P60 Observations
  98. Swift Status and XRT Calibration Uncertainties
  99. GRB 070917: Swift-XRT observations
  100. GRB 070917: R band observations

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