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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"

18488 results found.

  1. GRB 060602B: Swift-XRT Refined Analysis
  2. GRB 060602B: Swift-BAT Refined Analysis
  3. GRB 060602B: Swift/UVOT observations
  4. GRB 060602A: Swift-BAT Refined Analysis
  5. GRB 060602B: RTT150 optical observations
  6. GRB 060602B: Swift detection of a burst
  7. GRB060602 - SDSS Pre-Burst Observations
  8. GRB 060602: Swift detection of a burst
  9. GRB 060526: Break in X-ray light curve
  10. GRB 051227 : WIDGET simultaneous optical observations
  11. GRB 060526: Multiple Optical Flares
  12. GRB060502b: optical observations
  13. GRB 060526: Optical Flare
  14. GRB 060526: Refined analysis of the Swift-BAT burst
  15. GRB 060526: RTT150 optical observations
  16. GRB060526: Further Swift-UVOT Observations
  17. GRB 060526: Swift/XRT Team refined analysis
  18. GRB 060526: ROTSE-III Observations of Optical Counterpart
  19. GRB 060526: Watcher Observations
  20. GRB 060526: Continued emission for the Swift burst
  21. GRB 060526: Swift detection of a burst with x-ray and optical afterglow
  22. GRB 060413 : WIDGET simultaneous optical observations
  23. GRB 060522: Swift/UVOT Observations: Correction
  24. GRB 060522: Swift/UVOT Observations of the Optical Afterglow
  25. XMM-Newton observation of GRB060510b
  26. GRB 060522: Swift/XRT Team refined analysis
  27. GRB 060522: Swift-BAT Refined Analysis
  28. GRB 060522: Swift detection of a burst with possible optical afterglow
  29. GRB 060210: Jet Break in the XRT light curve
  30. GRB 060516: Refined analysis of the Swift-BAT burst
  31. GRB 060516: Swift detection of a burst
  32. GRB 060505 BAT refined analysis
  33. GRB 060515 BAT refined analysis
  34. GRB 060512: TAROT optical observation
  35. GRB 060515: Swift/XRT Team refined analysis
  36. GRB 060515: Swift/UVOT Upper Limits
  37. GRB 060515: Swift/XRT position
  38. GRB 060515: Super-LOTIS Observations
  39. GRB060515: Swift/UVOT initial observation
  40. GRB 060515: TAROT optical observation
  41. GRB 060515: ROTSE-III Optical Limits
  42. GRB 060515: Swift detection of a burst
  43. Swift/UVOT observations of GRB060512.
  44. GRB060512: Swift XRT Team refined analysis
  45. GRB 060512: Detection of NIR afterglow
  46. GRB 060512: Swift-BAT Refined Analysis
  47. GRB060512 Name Correction: LT Afterglow detection
  48. GRB060512: Liverpool Telescope Afterglow detection
  49. GRB 060512: Swift detection of a burst with an optical afterglow
  50. GRB 060510A: Swift/UVOT Detection of an Optical Afterglow
  51. GRB 060505: X-ray afterglow - Correction -
  52. GRB 060505: X-ray afterglow
  53. Konus-Wind observation of GRB 060510A
  54. GRB 060428a, SMARTS optical/IR afterglow detection
  55. GRB060510B: Swift XRT refined analysis
  56. GRB 060510B: Swift/UVOT Upper Limits
  57. GRB 060510A: Refined analysis of the Swift-BAT burst
  58. GRB 060510B: Swift-BAT Refined Analysis
  59. GRB060510A: XRT refined analysis
  60. GRB 060510B: Super-LOTIS Observations
  61. GRB 060510B: MDM Observations and candidate OT
  62. GRB 060510B: Swift detection of a burst
  63. GRB 060510: Swift detection of a burst with optical transient
  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 060507: Swift/UVOT Upper Limits
  69. GRB 060507: Swift XRT Team Refined Analysis
  70. GRB 060507: MDM Optical Upper Limit
  71. GRB060507: Swift XRT position
  72. GRB 060507: Swift detection of a burst
  73. GRB060505: Swift/UVOT Observations
  74. GRB 060505: Swift XRT Team Refined Analysis
  75. GRB 060505: Swift XRT afterglow canditate position
  76. GRB 060505: Swift-BAT detection of a weak burst
  77. GRB 060502B MDM Follow-up Observation
  78. GRB060502A, optical observation
  79. GRB 060502B: Swift/UVOT upper limits
  80. GRB 060502A: Swift/UVOT source detection
  81. GRB 060502B: MDM Optical Observation
  82. GRB 060502B: Refined analysis of the Swift-BAT short burst
  83. GRB060502B: Swift XRT Team refined analysis
  84. GRB060502B: correction to XRT position
  85. GRB 060502B: MASTER optical observations
  86. GRB 060502B: Swift detection of a short burst
  87. GRB060502: Swift-XRT refined analysis
  88. GRB 060502: Swift-BAT refined analysis
  89. GRB 060502: APO Spectroscopic Observations
  90. GRB060501: Swift UVOT followup observations
  91. GRB060502: Super-LOTIS Observations
  92. GRB 060502: Swift detection of a burst with an optical counterpart
  93. GRB 060501: MDM Observations
  94. GRB060501: Super-LOTIS observations
  95. GRB060501: P60 imaging and afterglow candidate
  96. GRB 060501: Refined analysis of the Swift-BAT burst
  97. GRB060501: Swift XRT position
  98. GRB 060501: ROTSE-III Optical Limits
  99. GRB 060501: Swift detection of a burst
  100. GRB060428B: optical observation

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