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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"

45777 results found.

  1. GRB 050906: Radio Observations
  2. GRB 050904: Keck I-band Imaging
  3. GRB050906: P60 Observations
  4. GRB 050904: more VLT NIR observations
  5. GRB 050904: BOOTES early R-band observation
  6. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  7. GRB 050906: Bright galaxy in BAT error box
  8. GRB 050906: Swift/BAT Detection of a possible burst
  9. GRB 050904: More SOAR
  10. GRB 050904: photometric redshift
  11. GRB 050904: Swift/UVOT observations
  12. GRB 050904: Afterglow Astrometry
  13. GRB 050904: NIR object inside the XRT error box
  14. GRB 050904: early Swift XRT analysis results
  15. GRB 050904: SOAR YJ and PROMPT Ic Observations
  16. GRB 050904: BAT refined analysis of partial data set
  17. GRB 050904: TAROT optical measurements
  18. GRB050904: Optical Observations
  19. GRB 050904: Environmental Constraints
  20. GRB 050904: Possible High-Redshift GRB
  21. GRB 050904: SOAR/PROMPT Observations
  22. GRB050904: P60 Observations
  23. GRB 050904: TAROT optical limits
  24. GRB050904: Swift-BAT detection of a probable burst
  25. Swift-BAT triggers 153461-153465 are not GRBs
  26. Retraction of Swift-BAT trigger #153355
  27. GRB 050824: MDM Observations
  28. GRB 050827: Swift XRT preliminary analysis results
  29. IBAS Alerts 2641 and 2642: not a real GRB
  30. Swift Trigger #152652 is not a GRB
  31. GRB 050827 : OSN 1.5m optical observations
  32. GRB 050827: P200 NIR Observations
  33. GRB050827: Swift/UVOT upper limits
  34. GRB 050827: Optical Limit
  35. GRB 050827: XRT possible afterglow detection
  36. GRB 050826 : Lulin R band observation
  37. GRB050824: Maidanak optical limits
  38. GRB050820A: RTT150 optical observations
  39. GRB050827: RTT150 optical observations
  40. GRB 050827: Swift-BAT refined analysis
  41. GRB050827: Swift-BAT detection of a burst
  42. Subaru Observations of GRB050724
  43. GRB 050826: Optical Candidate
  44. GRB050824, HETE-2 Observation
  45. GRB 050826: Swift XRT preliminary analysis results
  46. GRB 050826: BAT refined analysis
  47. GRB050826: Swift/UVOT early upper limits
  48. GRB050824: First 2 hours of power low optical decay?
  49. GRB 050826: Swift XRT position
  50. GRB050826: Swift-BAT detection of a long burst
  51. GRB050824: MASTER final analysis of the OT observations
  52. Swift-BAT trigger 152038 is definitely not a GRB
  53. GRB050824: CORRECTION to UVOT observing times
  54. Swift-BAT trigger 152038 is probably not a GRB
  55. GRB050824: Swift/UVOT detection of fading afterglow
  56. GRB050824: decay of the XRT light curve and updated X-ray spectrum
  57. GRB050824, I-band imaging
  58. GRB050824: Radio Observations
  59. GRB 050824: Spectroscopic redshift from the VLT
  60. GRB 050822: refined XRT analysis
  61. GRB 050824: XRT refined analysis and possible afterglow detection
  62. GRB 050824: BAT refined analysis of a soft weak burst
  63. GRB050824: MASTER:OT decay
  64. GRB050824: MASTER observation OT
  65. GRB050805a: MASTER optical candidat
  66. GRB 050824: ROTSE-III Optical Limits
  67. GRB050824: Swift-BAT detection of a burst
  68. GRB 050824 optical candidate
  69. GRB050820A: RTT150 optical observations
  70. GRB050820a: PROMPT RcIc Observations
  71. GRB050815: Maidanak optical observation
  72. XRF050509c: Radio upper limits from GMRT
  73. VLT/UVES spectroscopy of GRB050820
  74. GRB050822: Swift/UVOT upper limits
  75. GRB 050820A BAT observations of second, larger episode of emission
  76. GRB050813: Maidanak I-band observations
  77. GRB 050822: Swift-BAT refined analysis
  78. GRB050525, GRB050607, GRB050802 BVRcIc field photometry
  79. GRB050820B at FRAM
  80. GRB050820A: RTT150 optical observations
  81. GRB 050820a - corrections to GCN 3846
  82. Swift/UVOT UV Photometry of GRB 050820B
  83. GRB 050822: ROTSE-III Prompt Optical Limits
  84. GRB 050822: Swift detection of a long burst
  85. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  86. GRB050820A: Radio Observation
  87. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  88. GRB050820a BVRcIc field photometry
  89. GRB050820B XMM-Newton observation
  90. GRB 050820a: NIR Observations by WIRO
  91. GRB 050820B: Swift XRT position
  92. GRB050820B: Planned XMM-Newton observation
  93. GRB050820B: Refined analysis of the Swift-BAT burst
  94. GRB050820B: BAT-Swift detection of a bright GRB
  95. Swift/UVOT photometry of GRB050820
  96. GRB050820: refined XRT analysis
  97. GRB 050820: Early RAPTOR detections
  98. GRB 050820 Swift-BAT refined analysis
  99. GRB 050820: P60 Temporal Decay Index
  100. GRB 050820: High Resolution Spectroscopy from Keck

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