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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"

20212 results found.

  1. GRB 060801: XRT/SDSS Frame Offset and Refined XRT Position
  2. GRB060801: Radio Observations
  3. GRB 051109B: Bright spiral host galaxy at low redshift
  4. GRB060801: Swift/UVOT Upper Limits
  5. GRB 060801: Refined analysis of the Swift-BAT short hard burst
  6. GRB 060801, optical observation
  7. GRB 060801: Kanazawa Optical Observation
  8. GRB060729: ROTSE-III Observations of the Slow Optical Decay
  9. GRB 060719: TORTOREM optical upper limits
  10. GRB 060729: Swift-XRT refined analysis
  11. GRB 060729: Swift/UVOT Observations
  12. GRB 060729: ROTSE-III Detection of Optical Counterpart
  13. GRB 060729: Swift detection of a burst with an UVOT optical counterpart
  14. GRB 060728: Swift/UVOT Upper Limits
  15. GRB 060728, SMARTS optical/IR observations
  16. Swift/XRT preliminary analysis
  17. GRB 060728: Swift detection of a burst
  18. GRB 060714: Swift/UVOT Observations
  19. GRB060719: prompt NIR observations with REM
  20. GRB 060714: NOT observations
  21. GRB 060719: near-infrared afterglow
  22. GRB 060522: VLA observation
  23. GRB 060719: Swift/UVOT Upper Limits
  24. GRB 060719: VLT/ISAAC observations
  25. GRB 060719: Refined analysis of the Swift-BAT burst
  26. GRB 060719: XRT refined analysis
  27. GRB060719: REM NIR Observations
  28. GRB 060719: VLT observations
  29. GRB 060719: LCO optical observations
  30. GRB 060719: Swift detection of a burst
  31. GRB 060714: Refined analysis of the Swift-BAT burst
  32. GRB060717: Swift/UVOT upper limits
  33. GRB060717 - SDSS Pre-burst Observations
  34. GRB 060714: REM infrared observations
  35. GRB 060717, optical observation
  36. GRB 060717: Swift detection of a burst
  37. GRB 060714 : Liverpool Telescope Observations
  38. GRB 060708: VLT spectroscopy
  39. Swift trigger 219136 is probably not a GRB
  40. GRB 060714, optical observation
  41. GRB 060714: Swift detection of a burst with an UVOT optical afterglow
  42. GRB060712: P60 Observations
  43. GRB 060712: Swift/UVOT Upper Limits
  44. GRB 060712: XRT refined position
  45. GRB 060712: Refined analysis of the Swift-BAT burst
  46. GRB 060707: OA fading and redshift
  47. GCN 060708: Swift-UVOT Observations
  48. GCN 060707: Swift-UVOT observations
  49. GRB 060708: Swift detection of a burst with an UVOT countpart
  50. GRB 060707: Refined analysis of the Swift-BAT burst
  51. GRB 060515: Upper Limit on Host Galaxy
  52. GRB 060109: Upper Limit on Host Galaxy
  53. GRB 060105: Upper limit on Host Galaxy
  54. GRB 060614: Redshift
  55. Trigger 215279: Swift detection of a possible burst (GRB 060619)
  56. GRB050326: Host Galaxy Candidates
  57. GRB050124: Possible Host Galaxy
  58. GRB050223: Host Galaxy
  59. Konus-Wind observation of GRB 060614
  60. GRB060605: optical observation
  61. GRB 060605, optical observations
  62. GRB060614: SSO 1m observations
  63. GRB 060614: Swift-BAT refined analysis
  64. GRB 060614: Swift/UVOT Observations
  65. GRB 060614: Swift detection of a burst with a bright optical and X-ray counterpart
  66. GRB 060602A: Swift/XRT analysis
  67. GRB 060610: KAIT observations
  68. GRB 060607: RTT150 optical observations
  69. GRB 060607B: Swift-BAT Refined Analysis
  70. GRB060602A: Swift/UVOT upper limits
  71. GRB 060607B: Swift detection of a burst
  72. GCN 060607: Swift-UVOT obswervations.
  73. GRB 060607: Swift-BAT Refined Analysis
  74. GRB 060607: IR observations
  75. VLT/UVES observations of GRB 060607
  76. GRB 060605: RTT150 optical observations
  77. GRB 060607: REM NIR afterglow
  78. GRB 060607: Swift detection of a burst with bright optical counterpart
  79. GRB 060522: PROMPT Optical Limits
  80. GRB 060605: Xinglong TNT optical observations
  81. GRB060602B : REM infrared observations
  82. GRB060605: Swift/UVOT detections
  83. GRB 060605: Swift-XRT Team refined analysis
  84. GRB 060605: RTT150 optical observations
  85. GRB060604: Swift/UVOT detections
  86. GRB 060604A: ROTSE-III Optical Limits
  87. GRB 060604: Swift detection of a burst with possible optical counterpart
  88. GRB 060602B: Swift/UVOT observations
  89. GRB 060602B: RTT150 optical observations
  90. GRB 060211A : WIDGET simultaneous optical observations
  91. GRB060602A: optical observations(/transient?)
  92. GRB 060602B: Swift detection of a burst
  93. GRB060602 - SDSS Pre-Burst Observations
  94. GRB 060502A: Optical afterglow observations
  95. GRB 060526: Break in X-ray light curve
  96. GRB060526, optical observations
  97. GRB 051227 : WIDGET simultaneous optical observations
  98. GRB 051028 : WIDGET pre-trigger limit
  99. GRB060526: Optical counterpart from MIRO
  100. GRB 060526: RTT150 optical observations

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