CP violation at CDF Page: 2 of 15
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
A small amount of CP violation in the neutral kaon system observed in 1964 1)
is still the only experimentally observed violation of the symmetry between
particles and antiparticles. In the framework of the standard model the source
of this asymmetry is the weak interaction. The matrix relating weak interaction
eigenstates to mass eigenstates is the unitary CKM matrix:
Vud Vus Vub 1 - A AA3(p + ir)
VCKM = Vcd Vcs Vb = -A 1 - 2 -AA2
Vtd Vs VI AA(1 - p - i7) -AA2 1
where the second form of the matrix is an approximation due to Wolfenstein 2),
accurate to order A3, where A = sin9c. CP violation arises due to irreducible
phases in the CKM matrix unless 7 = 0. In this parameterization, they appear
in Vtd and Vu6, the elements connecting the first and third generations. A
prediction of the CKM model of CP violation is that the mixing amongst
generations is not arbitrary, but constrained by the unitarity of the matrix.
The most poorly known elements of the CKM matrix are those connecting the
first and third generations. The conditions of unitarity require
VtVtd + V Vcd + VubVud = 1 (2)
This constraint has a popular graphical representation, the unitarity triangle,
shown in Fig. 1. The angles # and r are the phases of the CKM matrix elements
Vub and Vtd; in the standard model they are expected to be large. The length
Vub Vtd _ Vtd
Figure 1: The (rescaled) unitarity triangle. In equation 2, divide by Vc*Vd =
AV4* and use Vc6 ~ Vs.
Here’s what’s next.
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Boudreau, J. CP violation at CDF, article, April 16, 2001; Batavia, Illinois. (digital.library.unt.edu/ark:/67531/metadc718756/m1/2/: accessed June 20, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.