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arXiv · hep-lat/0209055

Study of stochastic estimates of quark loops with unbiased subtraction

Nilmani Mathur·Shao-Jing Dong
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Abstract

Stochastic noise estimator method is a powerful tool to calculate the disconnected insertion involving quark loops. We study the variance reduction technique with unbiased subtraction. We use the complex $Z_2$ noise to calculate the quark loops on a $16^3 \times 24$ lattice with $β= 6.0$ and $κ$ = 0.154. Unbiased subtraction method is performed by using hoping parameter expansion. We report on the variance reduction for the point-split vector current as a function of the number of subtraction terms and the number of noise used.

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Nilmani Mathur, Shao-Jing Dong. 2002-09-04. Study of stochastic estimates of quark loops with unbiased subtraction. https://doi.org/10.1016/s0920-5632(03)01567-6

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