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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"

36329 results found.

  1. GRB 050416: Swift/UVOT refined analysis
  2. Swift-BAT detection of GRB 050416b
  3. IBAS GRB Alert # 2463: not a GRB
  4. GRB050412: Radio Observations
  5. GRB 050416: Swift/UVOT detection of afterglow emission
  6. GRB 050416: Swift-BAT refined analysis
  7. GRB 050416: ART observations
  8. GRB 050416,optical observation
  9. GRB 050416: KAIT observations
  10. GRB050416: P200 NIR Observations
  11. GRB 050416: Swift XRT Position
  12. GRB 050416: Radio observations
  13. Confirmation of OT for GRB050416
  14. GRB050416: P60 Afterglow Candidate
  15. Swift BAT/XRT Detection of GRB 050416
  16. GRB 050412: Subaru observations
  17. GRB 050408: RTT150 optical observations
  18. GRB 050412: PROMPT VRcIc Observations
  19. GRB 050408: Kuiper 1.5m observations
  20. GRB 050412: optical limit
  21. GRB 050412: optical observations
  22. GRB 050408: refined XRT analysis, no jet break seen yet
  23. GRB 050412: early Swift XRT analysis results
  24. GRB 050412 : XingLong optical observation
  25. GRB 050412: Swift-BAT refined analysis
  26. GRB 050412: ANU 2.3m observations
  27. GRB 050412: Early Optical/Ultraviolet Observations with
  28. GRB 050412: retraction of UVOT transient report
  29. GRB 050412: UVOT transient not in XRT error circle
  30. GRB 050408: SDSS Field Calibration
  31. GRB 050412: Optical limit
  32. GRB 050412: LCO Optical Observations
  33. GRB 050412: Optical observations
  34. GRB050412: P60 Observations
  35. GRB 050412: Swift XRT Position
  36. GRB050412: optical limit before and during GRB
  37. GRB 050412: LCO optical observations
  38. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  39. GRB 050412: IR and Optical observations
  40. GRB 050412: IR Observations
  41. GRB050408: Radio Observations
  42. GRB 050401: Optical limit
  43. GRB 050408: Optical limit
  44. GRB050410: P60 Observations
  45. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  46. GRB 050410, optical observations
  47. GRB 050408: PROMPT VRcIc Observations
  48. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  49. GRB 050410 R band Optical Observations
  50. GRB050410 : Null detection report
  51. GRB 050410, optical observations
  52. GRB050410: Radio Observations
  53. GRB 050408: Swift XRT measurement of possible jet break
  54. GRB050410: MASTER optical observations
  55. GRB 050410: Early observations with Swift-UVOT
  56. Swift-BAT detection of GRB 050410
  57. GRB 050410: Swift XRT Position
  58. GRB 050408: Retraction of Proposed Host Galaxy
  59. GRB 050408: Inconsistency of host galaxy identification
  60. GRB 050408: Subaru Observations
  61. GRB 050408: WIDGET simultaneous optical observations
  62. GRB 050408: SOAR UBVRc Observations
  63. GRB 050408: Properties of the Host Galaxy
  64. GRB 050408: Mercator Optical Observations
  65. GRB050408: Radio Observations
  66. GRB 050408: Swift XRT analysis
  67. GRB 050408, SMARTS optical/IR afterglow observations
  68. GRB 050408: Optical limit at 20 min after the burst
  69. GRB 050408, optical observations
  70. GRB 050408: Moderate-resolution Gemini Spectroscopy
  71. GRB 050408,optical observation
  72. GRB 050408 Optical Observations
  73. GRB 050408: Emission and absorption redshift
  74. GRB 050408: Mercator Optical Observations
  75. GRB 050408: Magellan astrometry and photometry
  76. GRB 050408: First Optical observations with TFOSC at the RTT150
  77. GRB 050408: steepening of the optical decay
  78. GRB 050408: Optical afterglow confirmed
  79. GRB 050408: opitcal observation
  80. GRB 050408, optical observations
  81. GRB 050408 optical candidate
  82. GRB 050408: Swift XRT Position
  83. GRB 050408: ROTSE-III Optical Limits
  84. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
  85. GRB050408: MASTER optical observations
  86. GRB050401: Radio Detection
  87. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  88. GRB 050406: Magellan optical observations
  89. GRB 050406: early Swift XRT analysis results
  90. GRB 050406 BAT refined analysis
  91. GRB 050406: Early observations with Swift-UVOT
  92. GRB 050406: Swift XRT Position
  93. Swift-BAT detection of GRB 050406
  94. Konus-Wind observation of GRB 050401
  95. GRB050401: Radio observation at 610 MHz with GMRT
  96. GRB 050401: VLT spectroscopic redshift
  97. GRB 050401 Optical Observations
  98. GRB 050401 BAT refined analysis
  99. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  100. GRB050401: TNG R-band observation

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