% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@INPROCEEDINGS{Engelhardt:859217,
      author       = {Engelhardt, M. and Green, J. and Hasan, N. and Krieg, S.
                      and Meinel, S. and Negele, J. and Pochinsky, A. and
                      Syritsyn, S.},
      title        = {{Q}uark orbital angular momentum in the proton evaluated
                      using a direct derivative method},
      volume       = {LATTICE2018},
      address      = {Trieste},
      publisher    = {SISSA},
      reportid     = {FZJ-2019-00098, PoS LATTICE2018 (2019) 115},
      series       = {Proceedings of Science},
      pages        = {7 p.},
      year         = {2019},
      note         = {7 pages, 3 figures, to appear in the proceedings of the
                      23rd International Spin Physics Symposium (SPIN2018), 10-14
                      September 2018, Ferrara, Italy, and in the proceedings of
                      the 36th Annual International Symposium on Lattice Field
                      Theory (LATTICE2018), 22-28 July 2018, Michigan State
                      University, East Lansing, Michigan, USA},
      abstract     = {Quark orbital angular momentum (OAM) in the proton can be
                      calculated directly given a Wigner function encoding the
                      simultaneous distribution of quark transverse positions and
                      momenta. This distribution can be accessed via proton matrix
                      elements of a quark bilocal operator (the separation in
                      which is Fourier conjugate to the quark momentum) featuring
                      a momentum transfer (which is Fourier conjugate to the quark
                      position). To generate the weighting by quark transverse
                      position needed to calculate OAM, a derivative with respect
                      to momentum transfer is consequently required. This
                      derivative is evaluated using a direct derivative method,
                      i.e., a method in which the momentum derivative of a
                      correlator is directly sampled in the lattice calculation,
                      as opposed to extracting it a posteriori from the numerical
                      correlator data. The method removes the bias stemming from
                      estimating the derivative a posteriori that was seen to
                      afflict a previous exploratory calculation. Data for Ji OAM
                      generated on a clover ensemble at pion mass $m_{\pi } =
                      317\, \mbox{MeV} $ are seen to agree with the result
                      obtained via the traditional Ji sum rule method. By varying
                      the gauge connection in the quark bilocal operator, also
                      Jaffe-Manohar OAM is extracted, and seen to be enhanced
                      significantly compared to Ji OAM.},
      month         = {Jul},
      date          = {2018-07-22},
      organization  = {36th Annual International Symposium on
                       Lattice Field Theory, East Lansing,
                       Michigan (USA), 22 Jul 2018 - 28 Jul
                       2018},
      cin          = {JSC},
      cid          = {I:(DE-Juel1)JSC-20090406},
      pnm          = {511 - Computational Science and Mathematical Methods
                      (POF3-511)},
      pid          = {G:(DE-HGF)POF3-511},
      typ          = {PUB:(DE-HGF)29 / PUB:(DE-HGF)8 / PUB:(DE-HGF)7},
      eprint       = {1901.00843},
      howpublished = {arXiv:1901.00843},
      archivePrefix = {arXiv},
      SLACcitation = {$\%\%CITATION$ = $arXiv:1901.00843;\%\%$},
      url          = {https://juser.fz-juelich.de/record/859217},
}