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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"

35957 results found.

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

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