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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"

25905 results found.

  1. GRB 060805: Swift detection of a burst
  2. GRB 060804: Swift UVOT observations
  3. GRB 060804: Swift-XRT Team Refined Analysis
  4. GRB 060804: Refined analysis of the Swift-BAT burst
  5. GRB 060804: Swift detection of a burst with a possible UVOT counterpart
  6. GRB 060728: Upper limits of the X-ray emission
  7. GRB 060801: no variability of optical sources
  8. GRB 060801: WSRT Radio Observations
  9. GRB 060801: XRT/SDSS Frame Offset and Refined XRT Position
  10. GRB060801: Radio Observations
  11. GRB 051109B: Bright spiral host galaxy at low redshift
  12. GRB 060801: optical observations at FORS2/VLT
  13. GRB060801: Swift/UVOT Upper Limits
  14. GRB 060801: optical observations at Hanle and Calar Alto
  15. GRB060801: optical upper limit in R
  16. GRB 060801: Swift XRT refined analysis
  17. GRB 060801: Refined analysis of the Swift-BAT short hard burst
  18. GRB 060801: Kanazawa Optical Observation
  19. GRB 060801: Swift detection of a short burst
  20. GRB060729: ROTSE-III Observations of the Slow Optical Decay
  21. Swift-BAT trigger 221873 is not a GRB or a Transient
  22. GRB 060729 redshift
  23. GRB 060729: Swift/UVOT Detections
  24. GRB 060729: Refined analysis of the Swift-BAT burst
  25. GRB 060729: Swift-XRT refined analysis
  26. GRB 060729: Swift/UVOT Observations
  27. GRB 060729: ROTSE-III Detection of Optical Counterpart
  28. GRB 060729: Swift detection of a burst with an UVOT optical counterpart
  29. GRB 060728: Swift/UVOT Upper Limits
  30. GRB 060728: Refined analysis of the Swift-BAT burst
  31. Swift/XRT preliminary analysis
  32. GRB 060728: Swift detection of a burst
  33. GRB060614 ATCA Radio Limits
  34. GRB 060218 (SN 2006aj): IR afterglow detection six months after the
  35. GRB 060714: Swift/UVOT Observations
  36. GRB060719: prompt NIR observations with REM
  37. GRB 060714: NOT observations
  38. GRB 060719: near-infrared afterglow
  39. GRB 060522: VLA observation
  40. GRB 060719: Swift/UVOT Upper Limits
  41. GRB 060719: VLT/ISAAC observations
  42. GRB 060719: Refined analysis of the Swift-BAT burst
  43. GRB 060719: XRT refined analysis
  44. GRB 060719: further analysis of VLT observations
  45. GRB 060719: optical limit by Pi-of-the-Sky
  46. GRB060719: FRAM early follow-up limit
  47. GRB 060719: prompt PROMPT observations
  48. GRB060719: REM NIR Observations
  49. GRB 060719: Continued LCO optical observations
  50. GRB 060719: LCO optical observations
  51. GRB 060719: Swift detection of a burst
  52. GRB 060717: Swift XRT refined analysis
  53. GRB 060714: OA fading and a possible host detection
  54. GRB060714: optical observations
  55. GRB 060717: NOT observations
  56. GRB 060714: Refined analysis of the Swift-BAT burst
  57. GRB 060717 optical upper limit
  58. GRB060717: Swift/UVOT upper limits
  59. GRB 060717: Swift XRT refined position
  60. GRB 060717: Swift-BAT refined analysis
  61. GRB 060714: REM infrared observations
  62. GRB 060717: Swift detection of a burst
  63. GRB060714: optical observations
  64. GRB 060714, SMARTS optical/IR afterglow observation
  65. GRB 060714 : Liverpool Telescope Observations
  66. GRB 060714: Swift XRT refined analysis
  67. GRB 060714: OA redshift
  68. GRB 060708: VLT spectroscopy
  69. GRB060708: MARGE low resolution spectrum observations
  70. Swift-BAT trigger 219136 is not a GRB
  71. GRB060707 possible optical confirmation
  72. Swift trigger 219136 is probably not a GRB
  73. GRB 060714: Swift detection of a burst with an UVOT optical afterglow
  74. GRB 060605: SkyNet Optical Limits
  75. GRB060712: P60 Observations
  76. GRB 060712: XRT refined analysis
  77. GRB 060712: Swift/UVOT Upper Limits
  78. GRB060526: optical observations
  79. GRB 060712: XRT refined position
  80. GRB 060712: Refined analysis of the Swift-BAT burst
  81. GRB 060712: Swift detection of a burst
  82. GRB 060708: PROMPT Optical Limits
  83. GRB 060707: OA fading and redshift
  84. GRB 060708: Swift-XRT refined analysis
  85. GCN 060708: Swift-UVOT Observations
  86. GRB 060708: Refined analysis of the Swift-BAT burst
  87. GCN 060707: Swift-UVOT observations
  88. GRB 060707: Swift-XRT refined analysis
  89. GRB 060708: Swift detection of a burst with an UVOT countpart
  90. GRB060707 possible optical confirmation
  91. GRB 060707: BOOTES-IR optical afterglow candidate
  92. GRB 060707: Refined analysis of the Swift-BAT burst
  93. GRB 060707: BOOTES-IR optical observation
  94. GRB060614: Possible SN Bump in UVOT U Band Light Curve
  95. GRB 060707: Swift detection of a burst
  96. GRB 060515: Upper Limit on Host Galaxy
  97. GRB 060614: SMARTS host galaxy observations
  98. GRB 060614: Detection of a Possible, Late-Time Rebrightening
  99. GRB 060109: Upper Limit on Host Galaxy
  100. GRB 060105: Upper limit on Host Galaxy

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