Unquenched determination of the kaon parameter B_K from improved staggered fermions

Physics – High Energy Physics – High Energy Physics - Lattice

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

15 pages, 6 figures

Scientific paper

10.1103/PhysRevD.73.114502

The use of improved staggered actions (HYP, Asqtad) has been proved to reduce the scaling corrections that affected previous calculations of B_K with unimproved (standard) staggered fermions in the quenched approximation. This improved behaviour allows us to perform a reliable calculation of B_K including quark vacuum polarization effects, using the MILC configurations with n_f=2+1 flavours of sea fermions. We perform such a calculation for a single lattice spacing, a=0.125 fm, and with kaons made up of degenerate quarks with m_s/2. The valence strange quark mass m_s is fixed to its physical value and we use two different values of the light sea quark masses. After a chiral extrapolation of the results to the physical value of the sea quark masses, we find \hat B_K = 0.83+-0.18, where the error is dominated by the uncertainty in the lattice to continuum matching at O(\alpha_s^2). The matching will need to be improved to get the precision needed to make full use of the experimental data on \epsilon_K to constrain the unitarity triangle.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Unquenched determination of the kaon parameter B_K from improved staggered fermions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Unquenched determination of the kaon parameter B_K from improved staggered fermions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Unquenched determination of the kaon parameter B_K from improved staggered fermions will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-413406

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.