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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
  1. GRB060512: Late-Time P200 Observations
  2. GRB060522: z = 5.11 Keck-LRIS Redshift
  3. GRB 060522: Swift/XRT Team refined analysis
  4. GRB 060522: Swift-BAT Refined Analysis
  5. GRB 060522: REM NIR observations
  6. GRB 060522: TNG optical observations
  7. GRB 060522: Swift detection of a burst with possible optical afterglow
  8. GRB 060512: reanalysis of optical spectra
  9. GRB 060515: NIR observation
  10. GRB 060210: Jet Break in the XRT light curve
  11. GRB 060516: Refined analysis of the Swift-BAT burst
  12. GRB 060512: TNG optical spectroscopy
  13. GRB 060516: Swift detection of a burst
  14. GRB060515: P200 NIR Observations
  15. GRB 060505 BAT refined analysis
  16. GRB 060515 BAT refined analysis
  17. GRB 060512: TAROT optical observation
  18. GRB 060515: Swift/XRT Team refined analysis
  19. GRB 060515: Swift/UVOT Upper Limits
  20. GRB 060515: Swift/XRT position
  21. GRB 060515: Super-LOTIS Observations
  22. GRB060515: Swift/UVOT initial observation
  23. GRB 060515: TAROT optical observation
  24. GRB 060515: ROTSE-III Optical Limits
  25. GRB 060515: Swift detection of a burst
  26. VLT optical spectroscopy of GRB 060512
  27. Swift/UVOT observations of GRB060512.
  28. GRB 060512: Subaru NIR observation
  29. GRB060512: Swift XRT Team refined analysis
  30. GRB 060512: 1.54m Kuiper Observations
  31. GRB 060512: Detection of NIR afterglow
  32. GRB 060512: P60 Observations
  33. GRB 060512: Swift-BAT Refined Analysis
  34. GRB 060505 - OT candidate + galaxy spectrum
  35. GRB 060512: optical decay
  36. GRB 060512: REM NIR observations
  37. GRB060512 - SDSS Pre-Burst Observations
  38. GRB060512 Name Correction: LT Afterglow detection
  39. GRB060512: Liverpool Telescope Afterglow detection
  40. GRB 060512: Swift detection of a burst with an optical afterglow
  41. GRB 060510A: Swift/UVOT Detection of an Optical Afterglow
  42. GRB 060505: X-ray afterglow - Correction -
  43. GRB 060505: X-ray afterglow
  44. Konus-Wind observation of GRB 060510A
  45. GRB060418: optical observations
  46. GRB 060428a, SMARTS optical/IR afterglow detection
  47. GRB060510B: Swift XRT refined analysis
  48. GRB 060510B: Swift/UVOT Upper Limits
  49. GRB 060510A: Refined analysis of the Swift-BAT burst
  50. GRB 060510B: Swift-BAT Refined Analysis
  51. GRB060510A: XRT refined analysis
  52. GRB060510 - SDSS Pre-Burst Observations
  53. GRB 060510b: Redshift
  54. GRB060510B : Faulkes North Telescope detection
  55. GRB 060510B : Planned XMM-Newton observation
  56. GRB 060510b: Gemini NIR observations
  57. GRB 060510B: Super-LOTIS Observations
  58. GRB 060510b: NIR observations
  59. GRB 060510B: Coordinate correction
  60. GRB 060510B: MDM Observations and candidate OT
  61. GRB 060510B: Swift detection of a burst
  62. GRB 060510: Swift detection of a burst with optical transient
  63. GRB060507: optical afterglow detection
  64. GRB060502B: improvement in the XRT afterglow position
  65. GRB 060507: BART limit
  66. GRB 060507: Final Refined analysis of the Swift-BAT burst
  67. GRB 060507: Swift-BAT Refined Analysis
  68. GRB 060505: PROMPT Observations
  69. GRB 060507: Swift/UVOT Upper Limits
  70. GRB 060507: Swift XRT Team Refined Analysis
  71. GRB 060507: MDM Optical Upper Limit
  72. GRB060507: Swift XRT position
  73. GRB 060507: Swift detection of a burst
  74. GRB 060429: Suzaku WAM observation
  75. GRB060505: Swift/UVOT Observations
  76. GRB 060505: Swift XRT Team Refined Analysis
  77. GRB060425: new MASTER survey method
  78. GRB 060306: Further Analysis of SOAR and APO NIR Observations
  79. GRB 060505: Swift XRT afterglow canditate position
  80. GRB 060502b: Second epoch Gemini observations
  81. GRB 060505: Swift-BAT detection of a weak burst
  82. GRB 060428B: spectroscopy
  83. GRB 060502B: optical observations
  84. GRB 060502B: AROMA refined photometric calibration
  85. GRB 060502B MDM Follow-up Observation
  86. GRB 060502b: Gemini imaging and spectroscopy
  87. GRB060502A, optical observation
  88. GRB 060502B: Swift/UVOT upper limits
  89. GRB 060502A: Swift/UVOT source detection
  90. GRB 060429: Refined IPN error box and Konus-Wind spectrum
  91. GRB 060502B: MDM Optical Observation
  92. GRB 060502B: AROMA optical observations
  93. GRB 060502B: Refined analysis of the Swift-BAT short burst
  94. GRB060502B: Swift XRT Team refined analysis
  95. Short GRB 060502B: Tautenburg Observation
  96. GRB 060427B Milagro GeV/TeV Observations
  97. GRB 060502A: TTT Observations
  98. GRB060502B: correction to XRT position
  99. GRB 060501: P60 Observations and Candidate Retraction
  100. GRB 060502B: Xinglong optical observation

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