TY  - CONF
AU  - Alexandrou, Constantia
AU  - Bacchio, Simone
AU  - Constantinou, Martha
AU  - Finkenrath, Jacob
AU  - Hadjiyiannakou, Kyriakos
AU  - Jansen, Karl
AU  - Koutsou, Giannis
AU  - Vaquero, Alejandro
TI  - Nucleon form factors from N<sub>f</sub>=2+1+1 twisted mass QCD at the physical point
JO  - Proceedings of Science / International School for Advanced Studies
VL  - (LATTICE2021)
IS  - arXiv:2112.06750
SN  - 1824-8039
CY  - Trieste
PB  - SISSA
M1  - PUBDB-2022-00991
M1  - arXiv:2112.06750
T2  - 1989580
SP  - 250
PY  - 2022
N1  - 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
AB  - 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.
T2  - 38th International Symposium on Lattice Field Theory 
CY  - 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
KW  - form factor: electromagnetic (INSPIRE)
KW  - mass: twist (INSPIRE)
KW  - form factor: axial (INSPIRE)
KW  - fermion: mass: twist (INSPIRE)
KW  - nucleon: form factor (INSPIRE)
KW  - error: statistical (INSPIRE)
KW  - lattice (INSPIRE)
KW  - clover (INSPIRE)
KW  - statistics (INSPIRE)
KW  - quantum chromodynamics (INSPIRE)
KW  - isoscalar (INSPIRE)
KW  - excited state (INSPIRE)
KW  - quark (INSPIRE)
LB  - PUB:(DE-HGF)16 ; PUB:(DE-HGF)8 ; PUB:(DE-HGF)7
DO  - DOI:10.22323/1.396.0250
UR  - https://bib-pubdb1.desy.de/record/474784
ER  -