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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"
  1. Swift-BAT trigger 221873 is not a GRB or a Transient
  2. GRB 060729 redshift
  3. GRB 060719: TORTOREM optical upper limits
  4. GRB 060729: Swift/UVOT Detections
  5. GRB 060729: Refined analysis of the Swift-BAT burst
  6. GRB 060729: Swift-XRT refined analysis
  7. GRB 060729 : Planned XMM-Newton observation
  8. GRB 060729: Swift/UVOT Observations
  9. GRB 060729: ROTSE-III Detection of Optical Counterpart
  10. GRB 060729: Swift detection of a burst with an UVOT optical counterpart
  11. GRB 060728: Swift/UVOT Upper Limits
  12. GRB 060728: Refined analysis of the Swift-BAT burst
  13. GRB 060728, SMARTS optical/IR observations
  14. Swift/XRT preliminary analysis
  15. GRB 060728: Swift detection of a burst
  16. GRB060614 ATCA Radio Limits
  17. GRB 060218 (SN 2006aj): IR afterglow detection six months after the
  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 060719: correction to the coordinates reported in GCN 5347
  23. GRB 060522: VLA observation
  24. GRB 060719: Swift/UVOT Upper Limits
  25. GRB 060719: VLT/ISAAC observations
  26. GRB 060719: Refined analysis of the Swift-BAT burst
  27. GRB 060719: XRT refined analysis
  28. GRB 060719: further analysis of VLT observations
  29. GRB 060719: optical limit by Pi-of-the-Sky
  30. GRB060719: FRAM early follow-up limit
  31. GRB 060719: prompt PROMPT observations
  32. GRB060719: REM NIR Observations
  33. GRB 060719: Continued LCO optical observations
  34. GRB 060719: VLT observations
  35. GRB 060719: LCO optical observations
  36. GRB 060719: Swift detection of a burst
  37. GRB 060717: Swift XRT refined analysis
  38. GRB 060714: OA fading and a possible host detection
  39. GRB060714: optical observations
  40. GRB 060717: NOT observations
  41. GRB 060714: Refined analysis of the Swift-BAT burst
  42. GRB 060717 optical upper limit
  43. GRB060717: Swift/UVOT upper limits
  44. GRB 060717: Swift XRT refined position
  45. GRB 060717: Swift-BAT refined analysis
  46. GRB060717 - SDSS Pre-burst Observations
  47. GRB 060714: REM infrared observations
  48. GRB 060717, optical observation
  49. GRB 060717: Swift detection of a burst
  50. GRB060714: correction to GCN 5324
  51. GRB060714: optical observations
  52. GRB 060714, SMARTS optical/IR afterglow observation
  53. GRB 060714 : Liverpool Telescope Observations
  54. GRB 060714: Swift XRT refined analysis
  55. GRB 060714: OA redshift
  56. GRB 060708: VLT spectroscopy
  57. GRB060708: MARGE low resolution spectrum observations
  58. GRB060714: optical observations
  59. Swift-BAT trigger 219136 is not a GRB
  60. Correction to Circular 5314: Circular refers to GRB 060714
  61. GRB060707 possible optical confirmation
  62. Swift trigger 219136 is probably not a GRB
  63. GRB 060714, optical observation
  64. GRB 060714: Swift detection of a burst with an UVOT optical afterglow
  65. GRB 060605: SkyNet Optical Limits
  66. GRB060712: P60 Observations
  67. GRB 060712: XRT refined analysis
  68. GRB 060712: Swift/UVOT Upper Limits
  69. GRB060526: optical observations
  70. GRB 060712: XRT refined position
  71. GRB 060712: Refined analysis of the Swift-BAT burst
  72. GRB060712: MASTER optical observation
  73. GRB120706: MASTER optical observation
  74. GRB 060712: Swift detection of a burst
  75. Host galaxy of GRB050904: 250 GHz upper limit with MAMBO at the IRAM 30m
  76. GRB 060708: PROMPT Optical Limits
  77. GRB 060707: OA fading and redshift
  78. GRB 060708: Swift-XRT refined analysis
  79. GCN 060708: Swift-UVOT Observations
  80. GRB 060708: Refined analysis of the Swift-BAT burst
  81. GCN 060707: Swift-UVOT observations
  82. GRB 060707: Swift-XRT refined analysis
  83. GRB 060708: Swift detection of a burst with an UVOT countpart
  84. GRB060707 possible optical confirmation
  85. GRB 060707: BOOTES-IR optical afterglow candidate
  86. GRB 060707: Refined analysis of the Swift-BAT burst
  87. GRB 060707: BOOTES-IR optical observation
  88. GRB060614: Possible SN Bump in UVOT U Band Light Curve
  89. GRB 060707: Swift detection of a burst
  90. GRB 060515: Upper Limit on Host Galaxy
  91. GRB 050223: Magellan redshift
  92. GRB 060614: SMARTS host galaxy observations
  93. GRB 060614: Detection of a Possible, Late-Time Rebrightening
  94. Correction to GCN 5278 & GCN 5279 (GRBs 060105 & 060109)
  95. GRB 060109: Upper Limit on Host Galaxy
  96. GRB 060105: Upper limit on Host Galaxy
  97. GRB060614: Detection of the host galaxy but no supernova emission
  98. GRB 060614: redshift confirmation
  99. GRB 060614: Redshift
  100. Swift-BAT trigger 215279 is not a GRB

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