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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"

36030 results found.

  1. GRB100420A: MITSuME optical upper limits
  2. GRB 100414A: CFHT optical observations
  3. GRB 100420A: Swift/UVOT Upper Limits
  4. GRB 100420A: XRT refined analysis
  5. GRB 100420A: Enhanced Swift-XRT position
  6. GRB 100418A: SARA second epoch
  7. GRB 100420A: SARA Upper Limits
  8. GRB 100418A: RTT150 observations during the optical afterglow maximum
  9. GRB 100418A: optical observations
  10. GRB 100418A: MASTER-Net optical observations
  11. GRB 100414A: Confirmation of the X-ray afterglow
  12. GRB 100418A: VLT optical observations
  13. GRB 100418A: SMA submm detection
  14. GRB 100420A: ROTSE-III Optical Limits
  15. GRB 100420A: Swift detection of a burst
  16. GRB 100418A PAIRITEL NIR Observations
  17. GRB 100418A: ROVOR optical afterglow detection
  18. GRB 100418A: Swift/UVOT Observations
  19. GRB 100418A: Gemini-N redshift confirmation
  20. GRB 100413A: GMRT observation of radio afterglow
  21. GRB 100418A: Swift-XRT Refined Analysis
  22. GRB 100418A: host galaxy detection in the SDSS
  23. GRB100418A: VLT/X-shooter redshift and photometry
  24. GRB 100418A: SARA observations
  25. GRB100414A: SAO RAS optical observations
  26. GRB 100418A: GROND observations; missing author list added
  27. GRB 100418A: GROND observations
  28. GRB 100418A: Swift-BAT refined analysis
  29. GRB 100418A: Enhanced Swift-XRT position
  30. GRB 100418A: ROTSE-III Optical Limits
  31. GRB 100418A: Swift detection of a burst with a possible optical afterglow
  32. GRB 100413A: Radio Afterglow Detection with the EVLA
  33. GRB 100414A: Suzaku WAM observation of the prompt emission
  34. GRB 100414A: Swift/UVOT Observations
  35. GRB 100414A: Gemini-N observation (correction)
  36. GRB 100414A: GROND Detection of the Optical Afterglow
  37. GRB 100414A: Gemini-N candidate and redshift
  38. GRB 100414A: Enhanced Swift-XRT position of candidate afterglow
  39. GRB 100413A: Suzaku WAM observation of the prompt emission
  40. GRB 100414A: Palomar Transient Factory Observations
  41. GRB 100413B: Swift Confirmation of Burst
  42. GRB 100414A: Swift-XRT detection of a possible X-ray afterglow
  43. GRB 100413A: Swift-BAT final refined analysis
  44. GRB 100414A: IPN Localization
  45. Konus-Wind observation of GRB 100414A (correction to GCN 10597)
  46. Konus-Wind observation of GRB 100414B
  47. GRB 100415A: MAXI/GSC detection of a probable GRB
  48. GRB 100414A: Fermi GBM detection
  49. GRB100414A: Fermi LAT detection
  50. GRB 100413B : Swift detection of a burst
  51. GRB 100413A: GROND Upper limits
  52. GRB 100413A: Swift/UVOT Upper Limits
  53. Konus-Wind observation of GRB 100413A
  54. GRB 100413A: Faulkes Telescope South observations
  55. Tentative redshift of GRB100413A from X-ray data
  56. GRB 100413A: SARA upper limit
  57. GRB 100413A: Swift-XRT Refined Analysis
  58. GRB 100413A: Swift-BAT initial refined analysis
  59. GRB 100413A: Enhanced Swift-XRT position
  60. GRB 100413: xinglong TNT optical upper limit
  61. GRB 100413A: MASTER-Net optical observations
  62. GRB 100413A: Swift detection of a burst
  63. Swift-BAT trigger 419015 is not astrophysical
  64. Trigger 419015 is probably not a GRB
  65. GRB100401A: GROND Upper Limits
  66. INTEGRAL Alert n. 5995: MASTER-Net optical observations
  67. IBAS Alert n. 5996: not a GRB
  68. IBAS Alert n. 5995: not a GRB
  69. GRB 100331B: GROND Upper limits
  70. GRB 100401A: Swift/UVOT Upper Limit
  71. Swift/BAT trigger 417974 (GRB100401A): Swift/XRT observations
  72. GRB 100401A: Fermi GBM detection
  73. GRB 100401A Burst, possibly short, detected in ground analysis of BAT data
  74. GRB 100331B: BOOTES-3 observations
  75. GRB 100316A: R-band limit
  76. GRB 100324B: Suzaku WAM observation of the prompt emission
  77. GRB 100331B: Swift/UVOT Upper Limits
  78. GRB 100331B: Swift/XRT possible afterglow candidate
  79. GRB 100331B: SuperAGILE Localization of a Long GRB
  80. INTEGRAL trigger 5994 (GRB100331A): Swift/XRT observations
  81. INTEGRAL trigger 5994 / GRB 100331A: GROND detection of a variable source
  82. GRB 100331A: BOOTES-3 observations
  83. Konus-Wind observation of GRB 100324B
  84. GRB 100331A: A long GRB detected by INTEGRAL
  85. IPN triangulation of GRB100324B
  86. Konus-Wind observation of GRB 100322A
  87. GRB 100322A: Suzaku WAM observation of the prompt emission
  88. GRB 100325A: Fermi LAT detection
  89. GROND observations of GRB100316D/SN2010bh
  90. GRB 100325A: Fermi GBM detection
  91. GRB 100324A: GROND observations
  92. GRB 100324A found in ground analysis of BAT data
  93. Emerging Supernova in the Afterglow of GRB 100316D
  94. GRB 100322B or possible Galactic transient detected in ground analysis of BAT data
  95. GRB 100316D: Spectroscopic Discovery of a Supernova from Magellan
  96. GRB 100322A: Fermi GBM detection
  97. GRB 100316D: ATCA radio observations
  98. GRB 100319A: correction to GCN 10527
  99. Probable SGR 1833-0832: Swift-XRT refined analysis
  100. GRB 100219A: MASTER-Net optical alert observations

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