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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"

45781 results found.

  1. GRB 060108: Swift/UVOT upper limits
  2. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  3. GRB060108: SDSS pre-burst observations
  4. GRB060108: Faulkes Telescope observation
  5. GRB060108, optical observation
  6. GRB 060108: Refined analysis of the Swift-BAT burst
  7. GRB 060108: Swift XRT position
  8. GRB060108: Swift detection of its 100th GRB
  9. GRB 060105: pseudo-z from spectral parameters of the prompt emission
  10. GRB 060105: Radio observations
  11. GRB 060105: MDM Observation
  12. Konus-Wind observation of GRB 060105
  13. GRB 060105: ISAS observations and near IR upper limit
  14. GRB 060105: Swift/UVOT upper limits
  15. GRB 060105: Mitsume optical observations
  16. GRB 060105: BAT refined analysis
  17. GRB 060105: XRT refined analysis
  18. GRB060105: Suzaku-XIS and -HXD observation plan
  19. GRB060105, optical observation
  20. GRB060105 : Kiso optical observation
  21. GRB060105: Swift detection of a bright long burst
  22. Swift-BAT trigger 175653 is not an astrophysical source
  23. GRB 060102: MDM Observation
  24. Swift-BAT trigger 175653 is probably not a GRB
  25. GRB 060102: Swift-BAT refined analysis
  26. Time Correction to GRB 060102
  27. GRB 060102: Swift-BAT detection of a burst
  28. GRB051211B: optical observations
  29. GRB051227: SARA Observations
  30. GRB 051221B: Optical Observations with Kuiper 1.54m
  31. GRB 051227: Likely host galaxy underlying afterglow position
  32. GRB 051227: optical observation
  33. GRB051221B: Radio observations
  34. GRB 051221A: VLA Radio Observations
  35. GRB051227: Radio Observations
  36. GRB 051227: Confirmed fading from Gemini observations
  37. GRB051227: further analysis of VLT images
  38. GRB 051227: optical afterglow
  39. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  40. GRB 051227: Gemini observations
  41. GRB 051227: Keck Spectroscopy
  42. GRB 051227: Magellan r'-band Imaging/Astrometry
  43. GRB 051227: refined analysis of VLT images
  44. GRB 051227: P60 Observations
  45. GRB 051227: MDM Observation
  46. GRB 051227: R-band object in the XRT error circle
  47. GRB 051227: Joint Swift-HETE Spectral Analysis
  48. GRB 051227: XRT refined analysis
  49. GRB 051227: Further analysis of the Swift-BAT burst
  50. GRB 051227: Refined analysis of the Swift-BAT burst
  51. GRB051227: SDSS pre-burst observations
  52. GRB 051227, optical observation
  53. GRB 051227: Swift detection of a burst
  54. GRB051117B: optical observation
  55. IBAS_alert n. 2719 : not a real GRB
  56. Konus-Wind observation of GRB 051221A
  57. GRB051221A: Suzaku WAM observation of the prompt emission
  58. GRB 051221A: MDM Optical Observations
  59. GRB051016: analysis of the XMM-Newton observation
  60. GRB 051221A: Detection at 251nm with Swift UVOT
  61. GRB 051221A: Chandra Afterglow Position
  62. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  63. GRB 051221B: ROTSE-III Optical Limits
  64. GRB 051221B: TAROT optical limits
  65. GRB 051221A: WSRT Radio Observations
  66. GRB 051221: Redshift from Gemini
  67. GRB 051221: Continued fading of optical afterglow
  68. GRB 051221B: Refined analysis of the Swift-BAT burst
  69. Possible GRB 051221B: MDM Optical Detection
  70. GRB 051221A: RAPTOR Fading Counterpart Constraint
  71. GRB 051221B: BOOTES optical observations.
  72. Possible GRB 051221B: Swift XRT position
  73. GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral
  74. Swift-BAT detection of a possible burst
  75. GRB 051221: Discovery of fading optical afterglow
  76. GRB 051221: Swift XRT refined analysis
  77. GRB 051221: Swift/UVOT upper limits
  78. GRB 051221: Possible nearby cluster
  79. GRB 051221: No variability in Gemini data
  80. GRB 051221: Correction to GCN #4368
  81. GRB 051221: Gemini observations
  82. GRB 051221: Improved astrometry of the IR counterpart
  83. GRB051221: K-band source
  84. GRB 051221: XRT position
  85. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  86. GRB 051221: IR Observations at GRB+1hr
  87. GRB 051221: Swift detection of a bright short burst
  88. Refined analysis of the SWIFT J1626.6-5156
  89. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  90. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  91. GRB051211A (=H3979): Refined Analysis
  92. GRB 051211B: optical afterglow
  93. Swift detection of an RS CVn flare star
  94. GRB051211A: possible optical candidate
  95. Swift Trigger 172767 is not a GRB
  96. GRB 051215: near-infrared observations
  97. GRB051215 - SDSS pre-burst observations
  98. GRB 051215: Swift detection of a possible burst
  99. GRB 051215: A short GRB in a cluster?
  100. GRB051211B: Probable radio afterglow

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