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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"

37724 results found.

  1. GRB050416B: IR observations
  2. GRB 050416: Swift/UVOT refined analysis
  3. Swift-BAT detection of GRB 050416b
  4. IBAS GRB Alert # 2463: not a GRB
  5. GRB050412: Radio Observations
  6. GRB 050416: Swift/UVOT detection of afterglow emission
  7. GRB 050416: Swift-BAT refined analysis
  8. GRB 050416: ART observations
  9. GRB 050416,optical observation
  10. GRB 050416: KAIT observations
  11. GRB050416: P200 NIR Observations
  12. GRB 050416: Swift XRT Position
  13. GRB 050416: Radio observations
  14. Confirmation of OT for GRB050416
  15. GRB050416: P60 Afterglow Candidate
  16. Swift BAT/XRT Detection of GRB 050416
  17. GRB 050412: Subaru observations
  18. GRB 050408: RTT150 optical observations
  19. GRB 050412: PROMPT VRcIc Observations
  20. GRB 050408: Kuiper 1.5m observations
  21. GRB 050412: optical limit
  22. GRB 050412: optical observations
  23. GRB 050408: refined XRT analysis, no jet break seen yet
  24. GRB 050412: early Swift XRT analysis results
  25. GRB 050412 : XingLong optical observation
  26. GRB 050412: Swift-BAT refined analysis
  27. GRB 050412: ANU 2.3m observations
  28. GRB 050412: Early Optical/Ultraviolet Observations with
  29. GRB 050412: retraction of UVOT transient report
  30. GRB 050412: UVOT transient not in XRT error circle
  31. GRB 050408: SDSS Field Calibration
  32. GRB 050412: Optical limit
  33. GRB 050412: LCO Optical Observations
  34. GRB 050412: Optical observations
  35. GRB050412: P60 Observations
  36. GRB 050412: Swift XRT Position
  37. GRB050412: optical limit before and during GRB
  38. GRB 050412: LCO optical observations
  39. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  40. GRB 050412: IR and Optical observations
  41. GRB 050412: IR Observations
  42. GRB050408: Radio Observations
  43. GRB 050401: Optical limit
  44. GRB 050408: Optical limit
  45. GRB050410: P60 Observations
  46. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  47. GRB 050410, optical observations
  48. GRB 050408: PROMPT VRcIc Observations
  49. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  50. GRB 050410 R band Optical Observations
  51. GRB050410 : Null detection report
  52. GRB 050410, optical observations
  53. GRB050410: Radio Observations
  54. GRB 050408: Swift XRT measurement of possible jet break
  55. GRB050410: MASTER optical observations
  56. GRB 050410: Early observations with Swift-UVOT
  57. Swift-BAT detection of GRB 050410
  58. GRB 050410: Swift XRT Position
  59. GRB 050408: Retraction of Proposed Host Galaxy
  60. GRB 050408: Inconsistency of host galaxy identification
  61. GRB 050408: Subaru Observations
  62. GRB 050408: WIDGET simultaneous optical observations
  63. GRB 050408: SOAR UBVRc Observations
  64. GRB 050408: Properties of the Host Galaxy
  65. GRB 050408: Mercator Optical Observations
  66. GRB050408: Radio Observations
  67. GRB 050408: Swift XRT analysis
  68. GRB 050408, SMARTS optical/IR afterglow observations
  69. GRB 050408: Optical limit at 20 min after the burst
  70. GRB 050408, optical observations
  71. GRB 050408: Moderate-resolution Gemini Spectroscopy
  72. GRB 050408,optical observation
  73. GRB 050408 Optical Observations
  74. GRB 050408: Emission and absorption redshift
  75. GRB 050408: Mercator Optical Observations
  76. GRB 050408: Magellan astrometry and photometry
  77. GRB 050408: First Optical observations with TFOSC at the RTT150
  78. GRB 050408: steepening of the optical decay
  79. GRB 050408: Optical afterglow confirmed
  80. GRB 050408: opitcal observation
  81. GRB 050408, optical observations
  82. GRB 050408 optical candidate
  83. GRB 050408: Swift XRT Position
  84. GRB 050408: ROTSE-III Optical Limits
  85. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
  86. GRB050408: MASTER optical observations
  87. GRB050401: Radio Detection
  88. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  89. GRB 050406: Magellan optical observations
  90. GRB 050406: early Swift XRT analysis results
  91. GRB 050406 BAT refined analysis
  92. GRB 050406: Early observations with Swift-UVOT
  93. GRB 050406: Swift XRT Position
  94. Swift-BAT detection of GRB 050406
  95. Konus-Wind observation of GRB 050401
  96. GRB050401: Radio observation at 610 MHz with GMRT
  97. GRB 050401: VLT spectroscopic redshift
  98. GRB 050401 Optical Observations
  99. GRB 050401 BAT refined analysis
  100. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)

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