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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"

24996 results found.

  1. GRB 060607: Swift-XRT Team refined analysis
  2. GRB 060607: IR observations
  3. GRB 060502B: A Bright Early-type Galaxy as Putative Host of the Short Burst
  4. GRB 060605: RTT150 optical observations
  5. GRB 060607: REM NIR afterglow
  6. GRB 060607: Swift detection of a burst with bright optical counterpart
  7. GRB 060522: PROMPT Optical Limits
  8. GRB 060605 BAT refined analysis
  9. GRB 060605: Xinglong TNT optical observations
  10. GRB060602B : REM infrared observations
  11. GRB060605: Swift/UVOT detections
  12. GRB 060605: Swift-XRT Team refined analysis
  13. GRB 060605: RTT150 optical observations
  14. GRB 060605: Swift detection of a burst with optical counterpart
  15. GRB060604: Swift/UVOT detections
  16. GRB 060604: Swift-XRT Team refined analysis
  17. GRB 060604: BAT refined analysis
  18. GRB 060604A: ROTSE-III Optical Limits
  19. GRB 060604: Swift detection of a burst with possible optical counterpart
  20. GRB 060602A: Swift-BAT Refined Analysis: Correction
  21. GRB 060602B: Swift-XRT Refined Analysis
  22. GRB 060602B: Swift-BAT Refined Analysis
  23. GRB 060602B: Swift/UVOT observations
  24. GRB 060602A: Swift-BAT Refined Analysis
  25. GRB 060211A : WIDGET simultaneous optical observations
  26. GRB060602A: optical observations(/transient?)
  27. GRB 060602B: Swift detection of a burst
  28. GRB060602B: BOOTES-IR candidate afterglow
  29. GRB060602 - SDSS Pre-Burst Observations
  30. GRB 060502A: Optical afterglow observations
  31. GRB 060526: Break in X-ray light curve
  32. GRB060526, optical observations
  33. GRB 051227 : WIDGET simultaneous optical observations
  34. GRB 051028 : WIDGET pre-trigger limit
  35. GRB060526: Optical counterpart from MIRO
  36. GRB 060526: RTT150 optical observations
  37. GRB060526: optical observations
  38. GRB 060526: REM observations
  39. GRB 060526: RTT150 optical observations, afterglow flattening
  40. GRB 060526: MDM-2.4m Observations
  41. GRB 060526: Refined analysis of the Swift-BAT burst
  42. GRB 060526: RTT150 optical observations
  43. GRB060526, optical observations
  44. GRB 060526: Swift/XRT Team refined analysis
  45. GRB 060526: ROTSE-III Observations of Optical Counterpart
  46. GRB 060526: Watcher Observations
  47. GRB060526 - SDSS Pre-burst Observations
  48. GRB 060526: Swift detection of a burst with x-ray and optical afterglow
  49. GRB 060413 : WIDGET simultaneous optical observations
  50. XMM-Newton observation of GRB060510b
  51. GRB060512: Late-Time P200 Observations
  52. GRB 060522: Swift-BAT Refined Analysis
  53. GRB 060522: REM NIR observations
  54. GRB 060522: TNG optical observations
  55. GRB 060515: NIR observation
  56. GRB 060210: Jet Break in the XRT light curve
  57. GRB 060516: Refined analysis of the Swift-BAT burst
  58. GRB060515: P200 NIR Observations
  59. GRB 060505 BAT refined analysis
  60. GRB 060515 BAT refined analysis
  61. GRB 060512: TAROT optical observation
  62. GRB 060515: Swift/XRT Team refined analysis
  63. GRB 060515: Swift/UVOT Upper Limits
  64. GRB 060515: Swift/XRT position
  65. GRB 060515: Super-LOTIS Observations
  66. GRB 060515: TAROT optical observation
  67. GRB 060512: Subaru NIR observation
  68. GRB060512: Swift XRT Team refined analysis
  69. GRB 060512: 1.54m Kuiper Observations
  70. GRB 060512: Detection of NIR afterglow
  71. GRB 060512: P60 Observations
  72. GRB 060512: Swift-BAT Refined Analysis
  73. GRB 060512: REM NIR observations
  74. GRB060512 - SDSS Pre-Burst Observations
  75. GRB 060512: Swift detection of a burst with an optical afterglow
  76. GRB 060505: X-ray afterglow - Correction -
  77. GRB 060505: X-ray afterglow
  78. Konus-Wind observation of GRB 060510A
  79. GRB060418: optical observations
  80. GRB 060428a, SMARTS optical/IR afterglow detection
  81. GRB060510B: Swift XRT refined analysis
  82. GRB 060510A: Refined analysis of the Swift-BAT burst
  83. GRB 060510B: Swift-BAT Refined Analysis
  84. GRB060510A: XRT refined analysis
  85. GRB060510 - SDSS Pre-Burst Observations
  86. GRB 060510B: Swift detection of a burst
  87. GRB 060510: Swift detection of a burst with optical transient
  88. GRB060507: optical afterglow detection
  89. GRB060502B: improvement in the XRT afterglow position
  90. GRB 060507: Final Refined analysis of the Swift-BAT burst
  91. GRB 060507: Swift-BAT Refined Analysis
  92. GRB 060505: PROMPT Observations
  93. GRB 060507: Swift XRT Team Refined Analysis
  94. GRB 060507: Swift detection of a burst
  95. GRB 060429: Suzaku WAM observation
  96. GRB060505: Swift/UVOT Observations
  97. GRB060425: new MASTER survey method
  98. GRB 060306: Further Analysis of SOAR and APO NIR Observations
  99. GRB 060505: Swift XRT afterglow canditate position
  100. GRB 060502b: Second epoch Gemini observations

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