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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36164 results found.

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

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