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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18349 results found.

  1. GRB 060515: Swift detection of a burst
  2. Swift/UVOT observations of GRB060512.
  3. GRB060512: Swift XRT Team refined analysis
  4. GRB 060512: Detection of NIR afterglow
  5. GRB 060512: Swift-BAT Refined Analysis
  6. GRB060512 Name Correction: LT Afterglow detection
  7. GRB060512: Liverpool Telescope Afterglow detection
  8. GRB 060512: Swift detection of a burst with an optical afterglow
  9. GRB 060510A: Swift/UVOT Detection of an Optical Afterglow
  10. GRB 060505: X-ray afterglow - Correction -
  11. GRB 060505: X-ray afterglow
  12. Konus-Wind observation of GRB 060510A
  13. GRB 060428a, SMARTS optical/IR afterglow detection
  14. GRB060510B: Swift XRT refined analysis
  15. GRB 060510B: Swift/UVOT Upper Limits
  16. GRB 060510A: Refined analysis of the Swift-BAT burst
  17. GRB 060510B: Swift-BAT Refined Analysis
  18. GRB060510A: XRT refined analysis
  19. GRB 060510B: Super-LOTIS Observations
  20. GRB 060510B: MDM Observations and candidate OT
  21. GRB 060510B: Swift detection of a burst
  22. GRB 060510: Swift detection of a burst with optical transient
  23. GRB060502B: improvement in the XRT afterglow position
  24. GRB 060507: BART limit
  25. GRB 060507: Final Refined analysis of the Swift-BAT burst
  26. GRB 060507: Swift-BAT Refined Analysis
  27. GRB 060507: Swift/UVOT Upper Limits
  28. GRB 060507: Swift XRT Team Refined Analysis
  29. GRB 060507: MDM Optical Upper Limit
  30. GRB060507: Swift XRT position
  31. GRB 060507: Swift detection of a burst
  32. GRB060505: Swift/UVOT Observations
  33. GRB 060505: Swift XRT Team Refined Analysis
  34. GRB 060505: Swift XRT afterglow canditate position
  35. GRB 060505: Swift-BAT detection of a weak burst
  36. GRB 060502B MDM Follow-up Observation
  37. GRB060502A, optical observation
  38. GRB 060502B: Swift/UVOT upper limits
  39. GRB 060502A: Swift/UVOT source detection
  40. GRB 060502B: MDM Optical Observation
  41. GRB 060502B: Refined analysis of the Swift-BAT short burst
  42. GRB060502B: Swift XRT Team refined analysis
  43. GRB060502B: correction to XRT position
  44. GRB 060502B: MASTER optical observations
  45. GRB 060502B: Swift detection of a short burst
  46. GRB060502: Swift-XRT refined analysis
  47. GRB 060502: Swift-BAT refined analysis
  48. GRB 060502: APO Spectroscopic Observations
  49. GRB060501: Swift UVOT followup observations
  50. GRB060502: Super-LOTIS Observations
  51. GRB 060502: Swift detection of a burst with an optical counterpart
  52. GRB 060501: MDM Observations
  53. GRB060501: Super-LOTIS observations
  54. GRB060501: P60 imaging and afterglow candidate
  55. GRB 060501: Refined analysis of the Swift-BAT burst
  56. GRB060501: Swift XRT position
  57. GRB 060501: ROTSE-III Optical Limits
  58. GRB 060501: Swift detection of a burst
  59. GRB060428B: optical observation
  60. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  61. GRB 060428B: MDM Observations
  62. GRB060428B: Swift XRT Team refined analysis
  63. GRB 060427B: IPN localization of a short hard burst
  64. GRB 060428B: Refined analysis of the Swift-BAT burst
  65. GRB 060428B: KAIT observations
  66. GRB060428A: Swift/UVOT observations.
  67. GRB060428B, optical observation
  68. GRB 060428A: Refined analysis of the Swift-BAT burst
  69. GRB060428A: Swift XRT Team refined analysis
  70. GRB 060428B: Swift detection of a burst
  71. GRB 060428: Swift detection of a burst
  72. GRB 060427: NOT observations
  73. GRB 060427: Swift/UVOT upper limits.
  74. GRB 060427: Refined analysis of the Swift-BAT burst
  75. GRB060427: Swift XRT Team refined analysis
  76. GRB060418: Swift XRT Team Further Refined Analysis
  77. GRB 060427, optical observation
  78. GRB 060427: Swift detection of a burst
  79. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  80. GRB 060424: Refined analysis of the Swift-BAT burst
  81. GRB 060424: Swift detection of a burst
  82. Swift-BAT detection of Mrk 421
  83. GRB060421: Swift/UVOT observations
  84. GRB 060421: Swift-BAT Refined Analysis
  85. GRB 060421: Swift-XRT refined analysis
  86. GRB 060418: prediction of t_break
  87. Konus-Wind observation of GRB 060418
  88. GRB(?)060421:MASTER optical limit
  89. GRB(?)060421 : XRT position
  90. Possible GRB060421: BART limits
  91. GRB(?) 060421: Swift detection of a burst
  92. GRB060418: Swift/UVOT Observations
  93. GRB 060418: FRAM early afterglow observation
  94. GRB 060418: Refined Analysis of the Swift-BAT burst
  95. VLT/UVES observations of GRB060418
  96. GRB060418: Swift XRT Team Refined Analysis
  97. GRB060418: Magellan/MIKE Spectroscopic Redshift
  98. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  99. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  100. GRB060413: Swift/UVOT upper limits

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