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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"

4613 results found.

  1. GRB 080804: GROND observations
  2. GRB080805 optical limit by "Pi of the Sky"
  3. GRB 080802: Swift-XRT Refined Analysis
  4. GRB 080727A: Early IR observations
  5. GRB 080727C: Swift XRT refined analysis
  6. GRB 080727B: Swift-XRT refined analysis
  7. GRB 080727A: Swift-XRT refined analysis
  8. GRB 080727B: Swift detection of a bright burst
  9. GRB 080723B - correction to flux conversion factor
  10. GRB 080723B - Swift-XRT refined analysis
  11. GRB 080723: Swift detection of a burst
  12. GRB 080721: Swift-XRT refined analysis
  13. GRB 080714: Swift-XRT refined analysis
  14. GRB 080603B: optical observations in MAO
  15. GRB 080710: Swift-XRT refined analysis
  16. GRB 080703: Swift-XRT refined analysis
  17. GRB 080702A: Swift-XRT Team refined analysis
  18. GRB 080701: Swift-XRT refined analysis
  19. GRB 080623: GROND upper limits
  20. GRB 080623: Swift-XRT refined analysis
  21. GRB 080613B: Swift-XRT refined analysis
  22. GRB080605: optical observation with the MITSuME-OAO telescope
  23. GRB 080605: Swift-XRT refined analysis
  24. GRB 080604: Swift-XRT refined analysis
  25. GRB 080603B: Swift-XRT refined analysis
  26. GRB 080603: Gemini-North redshift
  27. GRB 080524: Swift-BAT detection of a burst in ground analysis
  28. GRB 080523: VLT optical observations
  29. GRB 080520: Swift XRT Refined Analysis
  30. GRB 080520: Swift detection of a burst with optical afterglow
  31. GRB 080517: Swift-XRT refined analysis
  32. GRB 080517: Swift detection of a burst
  33. GRB 080516: Swift-XRT Team refined analysis
  34. GRB 080514B: KPNO 4m IR observations
  35. GRB 080507: Swift XRT analysis confirms the X-ray afterglow
  36. GRB 080506: Swift XRT refined analysis
  37. GRB080503, RIMOTS optical upper limit
  38. GRB080503 XRT refined analysis
  39. GRB 080430
  40. GRB 080430: Swift-XRT refined analysis
  41. GRB 080426: Swift-XRT refined analysis
  42. GRB 080420A: ROTSE-III Optical Limits on a possible short burst
  43. GRB 080413B: Swift XRT refined analysis
  44. GRB 080413A: Swift-XRT refined analysis
  45. GRB 080409: Swift detection of a burst
  46. GRB080328, RIMOTS optical upper limit
  47. GRB080310, late-time photometry with LBT
  48. GRB080325: XRT Refined Analysis
  49. GRB 080319D, Swift-BAT refined analysis
  50. GRB 080320: Swift XRT refined analysis
  51. GRB 080319D: Swift XRT refined analysis
  52. GRB 080320: Gemini-N optical afterglow
  53. GRB 080319B: Swift-XRT Team Refined Analysis
  54. GRB 080319C: Swift detection of a burst with an optical afterglow
  55. GRB080310: Optical observation by MITSuME telescope
  56. GRB080310: Super-LOTIS suggestion of brightening
  57. GRB 080310: Swift detection of a burst with optical afterglow
  58. GRB 080307: Swift-XRT Team refined analysis
  59. GRB 080307: Early RAPTOR Limits
  60. GRB080303: Swift XRT refined analysis
  61. GRB080229: Swift XRT refined analysis
  62. GRB080229: Possible optical afterglow
  63. GRB 080229: Swift detection of a bright burst
  64. GRB 080204: Suzaku WAM observation of the prompt emission
  65. GRB 080218B: Swift-XRT refined analysis
  66. GRB 080212: REM refined analysis
  67. GRB 080212: Gemini-South optical observations
  68. GRB 080212: GROND detects afterglow
  69. GRB 080212: REM NIR afterglow?
  70. GRB 080212: Swift-XRT Team refined analysis
  71. GRB 080212: DSS/2MASS Galaxy at XRT position
  72. GRB 080210: Swift-XRT Refined Analysis
  73. GRB 080207: Swift-XRT Refined Analysis
  74. GRB 080205: MASTER optical observation
  75. IPN localization of very hard GRB 080204
  76. GRB 080130: Swift-BAT refined analysis
  77. GRB 080123: Early afterglow detection with BATSS (BAT Slew Survey)
  78. GRB 080129, Swift-BAT refined analysis
  79. GRB 080122 : Suzaku WAM observation of the prompt emission
  80. GRB 080123: Swift-XRT refined analysis
  81. Swift UVOT Monitoring of the SN 2008D Brightening (Transient in NGC 2770)
  82. Swift UVOT Observations of the X-ray transient in NGC 2770
  83. Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
  84. GRB 071227: Swift-XRT refined analysis
  85. VLA radio detection of GRB 071122
  86. GRB 071122 Swift-XRT refined analysis
  87. GRB 071122: ROTSE-III Optical Limits
  88. GRB 071117: Swift-XRT refined analysis
  89. GRB 071112C: emission lines and refined VLT redshift
  90. GRB 071112C: Swift XRT refined analysis
  91. GRB 071112C: Palomar Pre-Imaging
  92. GRB 071112B: ROTSE-III Rapid Optical Limits
  93. GRB 071104: Swift-XRT Team Refined Analysis
  94. GRB 071101: Swift-XRT Team refined analysis
  95. GRB071101: Optical and NIR upper limits by KANATA
  96. GRB 071101: Swift detection of a burst
  97. GRB 071031: Swift-XRT Team refined analysis
  98. GRB071031: Rapid PROMPT Detections
  99. GRB 071028: Swift-XRT Team refined analysis
  100. GRB 071025: Kuiper Telescope Optical Observations

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