%0 Conference Paper
%A Alexandrou, Constantia
%A Bacchio, Simone
%A Constantinou, Martha
%A Finkenrath, Jacob
%A Hadjiyiannakou, Kyriakos
%A Jansen, Karl
%A Koutsou, Giannis
%A Vaquero, Alejandro
%T Nucleon form factors from N<sub>f</sub>=2+1+1 twisted mass QCD at the physical point
%J Proceedings of Science / International School for Advanced Studies
%V (LATTICE2021)
%N arXiv:2112.06750
%@ 1824-8039
%C Trieste
%I SISSA
%M PUBDB-2022-00991
%M arXiv:2112.06750
%B 1989580
%P 250
%D 2022
%Z 12 pages, 10 figures, 2 tables; proceedings of the 38th International Symposium on Lattice Field Theory (LATTICE2021), 26th-30th July, 2021, Zoom/Gather@Massachusetts Institute of Technology
%X We present the nucleon axial and electromagnetic form factors using N<sub>f</sub>=2+1+1 ensembles of twisted mass fermions with clover improvement and with masses tuned to their physical values. Excited state effects are studied using several sink-source time separations in the range 0.8 fm - 1.6 fm, exponentially increasing statistics with the separation such that statistical errors remain approximately constant. In addition, quark loop disconnected diagrams are included in order to extract the isoscalar axial form factors and the proton and neutron electromagnetic form factors, as well as their strange-quark contributions. The radii and moments are extracted by modelling the Q<sup>2</sup> dependence, including using the so-called z-expansion. A preliminary assessment of lattice cut-off effects is presented using two lattice spacings directly at the physical point.
%B 38th International Symposium on Lattice Field Theory 
%C 26 Jul 2021 - 30 Jul 2021, Zoom/Gather@Massachusetts Institute of Technology (USA)
Y2 26 Jul 2021 - 30 Jul 2021
M2 Zoom/Gather@Massachusetts Institute of Technology, USA
%K form factor: electromagnetic (INSPIRE)
%K mass: twist (INSPIRE)
%K form factor: axial (INSPIRE)
%K fermion: mass: twist (INSPIRE)
%K nucleon: form factor (INSPIRE)
%K error: statistical (INSPIRE)
%K lattice (INSPIRE)
%K clover (INSPIRE)
%K statistics (INSPIRE)
%K quantum chromodynamics (INSPIRE)
%K isoscalar (INSPIRE)
%K excited state (INSPIRE)
%K quark (INSPIRE)
%F PUB:(DE-HGF)16 ; PUB:(DE-HGF)8 ; PUB:(DE-HGF)7
%9 Journal ArticleContribution to a conference proceedingsContribution to a book
%R 10.22323/1.396.0250
%U https://bib-pubdb1.desy.de/record/474784