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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"

16023 results found.

  1. GRB 061028: TAROT Calern observatory optical observations
  2. GRB061025: ROTSE-III Confirmation of Optical Counterpart
  3. GRB 061025: REM observations
  4. GRB 061025: ROTSE-III Optical Limits
  5. GRB 061021: Swift/UVOT Observation
  6. GRB060904b: optical observations
  7. GRB061019: optical observations
  8. GRB061019: optical observations
  9. GRB 061019: dust-scattered X-ray halo detected in Swift/XRT
  10. GRB 060930: MARGE Optical Limits
  11. GRB 061019: Swift/UVOT upper limit
  12. GRB 061019: SMARTS afterglow confirmation
  13. GRB 061019: TAROT La Silla observatory optical observations
  14. GRB 061019: REM K-band candidate afterglow
  15. GRB 060825: GORT Observations
  16. GRB 061007: Second Epoch ATCA Radio Observations
  17. GRB 061006: astrometry-corrected XRT position
  18. GRB 061007: ATCA Radio Observations
  19. GRB 061006: optical afterglow
  20. GRB 061007: OA fading and VLT redshift
  21. GRB 061006: Swift/UVOT optical observations
  22. GRB 061007 - FTS early brightening and power law decay
  23. GRB 061007: Swift detection of a burst with an optical counterpart
  24. GRB 061007: ROTSE-III Detection of Optical Counterpart
  25. GRB 061004: Optical afterglow candidate and redshift
  26. GRB 061004: Las Campanas Optical/NIR Observations
  27. GRB061004: Swift/UVOT optical observations
  28. GRB 060930: Xinglong TNT optical observations
  29. GRB 060929: Swift/UVOT Optical Observations
  30. GRB 060930: ROTSE-III Optical Limits
  31. GRB 060927 : GAO 150cm telescope optical observation
  32. GRB060929: Optical limit
  33. GRB 060929: BOOTES-IR & OSN observations
  34. GRB060908: optical observations
  35. GRB 060729: An update on the late-time Swift observations
  36. GRB060923C: optical limit
  37. GRB060927: optical observations
  38. GRB 060926: Swift-UVOT UVW1 Detection Retraction
  39. GRB 060927: Swift/UVOT Optical Observations
  40. GRB 060927: Early color
  41. GRB 060927: Swift XRT Team refined analysis
  42. GRB 060927 optical limit
  43. GRB 060927: Xinglong TNT optical observations
  44. GRB 060927, optical observation
  45. GRB 060927 : Kiso optical observation
  46. GRB 060927: optical afterglow confirmation
  47. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  48. Swift XRT boresight
  49. GRB060926: VLT redshift
  50. GRB 060926: Swift-UVOT Detections
  51. GRB 060926: BOOTES-IR observations
  52. GRB060926 OPTIMA-Burst optical observation
  53. GRB 060926: MASTER optical observation
  54. GRB060923C: AROMA optical obsevation
  55. GRB 060923C, optical observation
  56. GRB060923B: Swift/UVOT upper limits
  57. GRB 060923C: Keck Observations
  58. GRB 060923C: Xinglong TNT optical observations
  59. GRB060923C : Faulkes Telescope South optical limits
  60. GRB060923C: Faulkes Telescope North optical observations
  61. GRB 060923C: optical observation
  62. GRB060923: Faulkes Telescope North optical observations
  63. GRB060919: Swift/UVOT optical observations
  64. GRB 060919 : Faulkes South Telescope Observations
  65. GRB 060919: TAROT optical observations
  66. GRB 060912A: Probable Host Galaxy
  67. GRB 060912: Redshift of nearby 2MASS galaxy
  68. GRB060912: optical observations
  69. GRB060912: Swift/UVOT Observations
  70. GRB060912: OPTIMA-Burst optical observations
  71. GRB 060912: Correction to GCN 5559
  72. GRB 060912: Xinglong TNT optical observations
  73. GRB 060912: Swift detection of a burst with an optical afterglow
  74. GRB060906: Danish/DFOSC optical observations
  75. GRB 060908: Swift/UVOT Observations
  76. GRB 060908: Danish/DFOSC optical observations
  77. GRB 060904B: Kiso Optical observation
  78. GRB 060904A : Optical limit
  79. GRB 060908: REM optical prompt observation
  80. GRB 060908: Swift detection of a burst with a bright optical counterpart
  81. GRB060906 , optical observation
  82. GRB060904b optical detections (delayed report due to internet outage)
  83. GRB 060906: optical observation
  84. GRB 060906: Early RAPTOR optical limits
  85. GRB 060906: Swift/XRT Refined Analysis
  86. GRB 060906: Swift-UVOT observations
  87. VLT redshift of GRB 060906
  88. GRB 060906: KAIT observations
  89. GRB 060906: Confirmation of P60 Optical Afterglow
  90. GRB 060906 (?): P60 Optical Afterglow Candidate
  91. GRB060904b, optical observations
  92. GRB 060904b: SMARTS optical/IR afterglow observations
  93. GRB 060904B: RTT150 optical observations
  94. GRB060904A: Swift/UVOT optical observations
  95. GRB060904b: Optical observations with Swift/UVOT
  96. GRB 060904B: VLT redshift
  97. GRB 060904B: Optical observations at Crni Vrh
  98. GRB060904B: Watcher observations
  99. GRB 060904B BOOTES-IR and 1.5m OSN observations
  100. GRB 060904B: TAROT optical counterpart observations

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