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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"

37763 results found.

  1. GRB 050904: Afterglow Astrometry
  2. GRB 050904: NIR object inside the XRT error box
  3. GRB 050904: early Swift XRT analysis results
  4. GRB 050904: SOAR YJ and PROMPT Ic Observations
  5. GRB 050904: BAT refined analysis of partial data set
  6. GRB 050904: TAROT optical measurements
  7. GRB050904: Optical Observations
  8. GRB 050904: Environmental Constraints
  9. GRB 050904: Possible High-Redshift GRB
  10. GRB 050904: SOAR/PROMPT Observations
  11. GRB 050904: TAROT optical limits
  12. Swift-BAT triggers 153461-153465 are not GRBs
  13. GRB 050824: MDM Observations
  14. GRB 050827: Swift XRT preliminary analysis results
  15. IBAS Alerts 2641 and 2642: not a real GRB
  16. Swift Trigger #152652 is not a GRB
  17. GRB 050827 : OSN 1.5m optical observations
  18. GRB 050827: P200 NIR Observations
  19. GRB 050827: Optical Limit
  20. GRB 050827: XRT possible afterglow detection
  21. GRB 050826 : Lulin R band observation
  22. GRB050824: Maidanak optical limits
  23. GRB050820A: RTT150 optical observations
  24. GRB050827: RTT150 optical observations
  25. GRB 050827: Swift-BAT refined analysis
  26. GRB 050826: Optical Candidate
  27. GRB050824, HETE-2 Observation
  28. GRB 050826: Swift XRT preliminary analysis results
  29. GRB 050826: BAT refined analysis
  30. GRB050824: First 2 hours of power low optical decay?
  31. GRB 050826: Swift XRT position
  32. GRB050826: Swift-BAT detection of a long burst
  33. GRB050824: MASTER final analysis of the OT observations
  34. Possible GRB050825:MASTER optical observations
  35. Swift-BAT trigger 152038 is definitely not a GRB
  36. Swift-BAT trigger 152038 is probably not a GRB
  37. GRB050824: decay of the XRT light curve and updated X-ray spectrum
  38. GRB050824, I-band imaging
  39. GRB050824: Radio Observations
  40. GRB 050824: Spectroscopic redshift from the VLT
  41. GRB 050822: refined XRT analysis
  42. GRB 050824: XRT refined analysis and possible afterglow detection
  43. GRB 050824: BAT refined analysis of a soft weak burst
  44. GRB050824: MASTER:OT decay
  45. GRB050824: MASTER observation OT
  46. GRB050805a: MASTER optical candidat
  47. GRB 050824: ROTSE-III Optical Limits
  48. GRB050824: Swift-BAT detection of a burst
  49. GRB 050824 optical candidate
  50. GRB050820A: RTT150 optical observations
  51. GRB050820a: PROMPT RcIc Observations
  52. GRB050815: Maidanak optical observation
  53. XRF050509c: Radio upper limits from GMRT
  54. VLT/UVES spectroscopy of GRB050820
  55. GRB 050820A BAT observations of second, larger episode of emission
  56. GRB050813: Maidanak I-band observations
  57. GRB 050822: Swift-BAT refined analysis
  58. GRB050525, GRB050607, GRB050802 BVRcIc field photometry
  59. GRB050820B at FRAM
  60. GRB050820A: RTT150 optical observations
  61. GRB 050820a - corrections to GCN 3846
  62. Swift/UVOT UV Photometry of GRB 050820B
  63. GRB 050822: ROTSE-III Prompt Optical Limits
  64. GRB 050822: Swift detection of a long burst
  65. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  66. GRB050820A: Radio Observation
  67. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  68. GRB050820a BVRcIc field photometry
  69. GRB 050820a: NIR Observations by WIRO
  70. GRB 050820B: Swift XRT position
  71. GRB050820B: Refined analysis of the Swift-BAT burst
  72. GRB050820B: BAT-Swift detection of a bright GRB
  73. GRB050820: refined XRT analysis
  74. GRB 050820: Early RAPTOR detections
  75. GRB 050820 Swift-BAT refined analysis
  76. GRB 050820: P60 Temporal Decay Index
  77. GRB 050820: High Resolution Spectroscopy from Keck
  78. GRB050819: RTT150 optical observations
  79. GRB 050820: Swift detection of a GRB
  80. GRB 050819 Swift-BAT refined analysis
  81. GRB050819: Swift XRT position
  82. GRB050819: Swift-BAT detection of a weak burst
  83. Swift-BAT trigger 150993 is not a GRB
  84. Swift Trigger 150823 is HETE J1900.1-2455
  85. GRB 050817: Optical observations
  86. GRB 050815: Radio Observation
  87. GRB050814: Radio Observation
  88. GRB050817: Negative Optical Observations
  89. GRB 050814: continued fading
  90. GRB 050813: Radio Observations
  91. GRB050815: Refined analysis of the Swift-BAT burst
  92. GRB 050815: ROTSE-III Optical Limits
  93. GRB050815: Swift XRT afterglow localization
  94. GRB 050730: Third Epoch WSRT Radio Observations
  95. GRB050814: Fading red source
  96. GRB 050813: Gemini Spectra Revisited
  97. GRB 050813: Non-fading of afterglow candidate
  98. GRB 050814: XRT refined analysis
  99. GRB050814: Refined analysis of the Swift-BAT burst
  100. GRB050813: Gemini Imaging

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