The quark contents of the nucleon and their implication for dark matter search

Preprint number: CP3-Origins-2013-46 DNRF90 and DIAS-2013-46
Authors: Constantia Alexandrou (The Cyprus Institute & University of Cyprus), Martha Constantinou (University of Cyprus), Vincent Drach (NIC, DESY & CP3-origins & DIAS), Kyriakos Hadjiyiannakou (University of Cyprus), Karl Jansen (NIC, DESY), Giannis Koutsou (The Cyprus Institute), Alexei Strelchenko (University of Cyprus), and Alejandro Vaquero (The Cyprus Institute)
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We present results concerning the light and strange quark contents of the nucleon using Nf=2+1+1 flavours of maximally twisted mass fermions. The corresponding σ-terms are casting light on the origin of the nucleon mass and their values are important to interpret experimental data from direct dark matter searches. We discuss our strategy to estimate systematic uncertainties arising in our computations. Our preliminary results for the σ−terms read σπN = 37(2.6)(24.7) \mev and σs=28(8)(10) \mev. We present our recent final analysis of the yN parameter and found yN=0.135(46) including systematics.