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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"

37694 results found.

  1. GRB 050408: SDSS Field Calibration
  2. GRB 050412: Optical limit
  3. GRB 050412: LCO Optical Observations
  4. GRB 050412: Optical observations
  5. GRB050412: P60 Observations
  6. GRB 050412: Swift XRT Position
  7. GRB050412: optical limit before and during GRB
  8. GRB 050412: LCO optical observations
  9. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  10. GRB 050412: IR and Optical observations
  11. GRB 050412: IR Observations
  12. GRB050408: Radio Observations
  13. GRB 050401: Optical limit
  14. GRB 050408: Optical limit
  15. GRB050410: P60 Observations
  16. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  17. GRB 050410, optical observations
  18. GRB 050408: PROMPT VRcIc Observations
  19. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  20. GRB 050410 R band Optical Observations
  21. GRB050410 : Null detection report
  22. GRB 050410, optical observations
  23. GRB050410: Radio Observations
  24. GRB 050408: Swift XRT measurement of possible jet break
  25. GRB050410: MASTER optical observations
  26. GRB 050410: Early observations with Swift-UVOT
  27. Swift-BAT detection of GRB 050410
  28. GRB 050410: Swift XRT Position
  29. GRB 050408: Retraction of Proposed Host Galaxy
  30. GRB 050408: Inconsistency of host galaxy identification
  31. GRB 050408: Subaru Observations
  32. GRB 050408: WIDGET simultaneous optical observations
  33. GRB 050408: SOAR UBVRc Observations
  34. GRB 050408: Properties of the Host Galaxy
  35. GRB 050408: Mercator Optical Observations
  36. GRB050408: Radio Observations
  37. GRB 050408: Swift XRT analysis
  38. GRB 050408, SMARTS optical/IR afterglow observations
  39. GRB 050408: Optical limit at 20 min after the burst
  40. GRB 050408, optical observations
  41. GRB 050408: Moderate-resolution Gemini Spectroscopy
  42. GRB 050408,optical observation
  43. GRB 050408 Optical Observations
  44. GRB 050408: Emission and absorption redshift
  45. GRB 050408: Mercator Optical Observations
  46. GRB 050408: Magellan astrometry and photometry
  47. GRB 050408: First Optical observations with TFOSC at the RTT150
  48. GRB 050408: steepening of the optical decay
  49. GRB 050408: Optical afterglow confirmed
  50. GRB 050408: opitcal observation
  51. GRB 050408, optical observations
  52. GRB 050408 optical candidate
  53. GRB 050408: Swift XRT Position
  54. GRB 050408: ROTSE-III Optical Limits
  55. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
  56. GRB050408: MASTER optical observations
  57. GRB050401: Radio Detection
  58. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  59. GRB 050406: Magellan optical observations
  60. GRB 050406: early Swift XRT analysis results
  61. GRB 050406 BAT refined analysis
  62. GRB 050406: Early observations with Swift-UVOT
  63. GRB 050406: Swift XRT Position
  64. Swift-BAT detection of GRB 050406
  65. Konus-Wind observation of GRB 050401
  66. GRB050401: Radio observation at 610 MHz with GMRT
  67. GRB 050401: VLT spectroscopic redshift
  68. GRB 050401 Optical Observations
  69. GRB 050401 BAT refined analysis
  70. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  71. GRB050401: TNG R-band observation
  72. GRB 050402A: IR Analysis
  73. GRB 050402A: IR Observations
  74. GRB 050402: Early observations with Swift-UVOT
  75. Swift Trigger 113225: P60 Observations
  76. GRB 050401: Optical afterglow confirmed
  77. GRB 050401: Optical afterglow candidate
  78. Swift-BAT detection of GRB 050401
  79. GRB 050401: Prompt XRT position
  80. Retraction of three Swift GRB triggers
  81. GRB050331: No Afterglow Detected
  82. Swift-BAT detection of GRB 050331b
  83. GRB 050331: Swift UVOT Source
  84. Swift-BAT detection of GRB 050331
  85. GRB 050331: Swift XRT Position
  86. GRB050319: radio observation
  87. Konus-Wind observation of GRB 050326
  88. GRB 050326: Early observations with Swift-UVOT
  89. GRB 050326 XMM-Newton observation
  90. GRB 050326 : Planned XMM-Newton observation
  91. GRB 050326: Swift XRT Position
  92. GRB050326: optical limit 33min before GRB
  93. GRB 050326 BAT refined analysis
  94. GRB050326: delayed XRT observation
  95. Swift-BAT detection of a bright GRB 050326
  96. GRB050319, color indices
  97. GRB050319: RTT150 Optical Observations
  98. Swift-BAT trigger 112060 is not a real GRB
  99. GRB 050319: Absorption redshift from the Nordic Optical Telescope
  100. GRB 050319: ROTSE-III Refined Analysis

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