Bulletin of the American Physical Society
APS April Meeting 2013
Volume 58, Number 4
Saturday–Tuesday, April 13–16, 2013; Denver, Colorado
Session Q13: Hadronic Physics |
Hide Abstracts |
Sponsoring Units: DNP Chair: Mark Dalton, University of Virginia Room: Plaza Court 2 |
Monday, April 15, 2013 10:45AM - 10:57AM |
Q13.00001: The Study of the D(e,e'p)n Reaction at High Four- Momentum Transfer Hari Khanal D(e,e'p)n reaction mechanism studies at high four -momentum transfer $Q^2$ are very important to understand the dynamics of the two nucleons at very short space time separation. The E01-020 experiment, carried out in HallA at Jefferson Lab, aimed at determining D(e,e'p)n cross sections for several values of constant $Q^2$ over wide range of kinematic settings. The angular distribution of the recoiling neutron at $Q^2$, 0.8 and 2.1 $(GeV/c)^2$ as a function of missing momenta and absolute differential cross section of electro-disintegration of deuteron as a function of recoiling momenta will be presented at Aps April Meeting held at Colorado, Denver. [Preview Abstract] |
Monday, April 15, 2013 10:57AM - 11:09AM |
Q13.00002: Three-Nucleon Short Range Correlations studies in Inclusive Scattering for $x_{bj}>2$ Zhihong Ye, John Arrington Short range correlations (SRC) can be studied in inclusive quasi-elastic electron scattering as the ratio of the cross sections of heavy to light nuclei provides a measure two-nucleon SRC (2N-SRC) and three-nucleon SRC (3N-SRC) in the region of $1 < x_{bj}$ and $< 2$ $2 < x_{bj} < 3$ regions, respectively. Recent experiments at Jefferson Lab confirmed the early measurements while including a wider range of nuclei and an extension into the 3N-SRC region. Measurements in the 3N region, however, suffer from poor experimental precision. Meanwhile, an exclusive measurement, also at Jefferson Lab, showed a strong isospin dependence of 2N-SRCs. Experiment E08014 was designed to study the onset of 3N-SRC for $x_{bj}>2$ with better accuracy, and to examine the isospin dependence of SRCs in inclusive scattering using the calcium isotopes. E08014 ran in Hall~A in 2011 and we will briefly present the experimental setup along with status of the data analysis followed by a discussion of the preliminary results. [Preview Abstract] |
Monday, April 15, 2013 11:09AM - 11:21AM |
Q13.00003: Short-range nuclear structure and the EMC effect: understanding the connection Nadia Fomin Inclusive electron scattering has proven to be an exceptional tool for studying short range structure in nuclei. Measurements of the EMC effect (at $x < 1$) are aimed at studying in-medium modification of the nucleon structure functions. On the other hand, inclusive measurements at $x>1$ focus on short range correlations (SRCs) between nucleons. Recent data on the EMC effect from Jefferson Lab suggest a sensitivity to short range nuclear structure related to NN correlations at $x>1$. The high precision results on the EMC effect and the ratios at $x>1$ have a linear relationship, suggesting a common physics explanation. Results from both experiments will be reviewed, the meaning of the correlation explored, plans for future measurements will be discussed. [Preview Abstract] |
Monday, April 15, 2013 11:21AM - 11:33AM |
Q13.00004: Flavor Dependence of the EMC Effect via Inclusive Electron Scattering from $^{40}$Ca and $^{48}$Ca David Gaskell The modification of the quark distribution functions in nuclei, the EMC effect, has been a topic of intense experimental and theoretical study since its original observation in 1983. At present there is no uniformly accepted explanation for the origin of the EMC effect and new observables are required to discriminate among the plethora of models put forward. Recent calculations suggest that the up quark distribution in a nucleus is modified differently than the down quark distribution for the case $N \neq Z$. A number of techniques have been proposed to measure this flavor dependence of the EMC effect, including semi-inclusive deep inelastic scattering (SIDIS) and parity violating deep inelastic scattering (PVDIS). In this talk, I will examine the possibility of determining the flavor dependence of the EMC effect via inclusive electron scattering from $^{48}$Ca and $^{40}$Ca. [Preview Abstract] |
Monday, April 15, 2013 11:33AM - 11:45AM |
Q13.00005: Parity-violating deep inelastic scattering with SoLID at Jefferson Lab Seamus Riordan Deep inelastic electron scattering has been an invaluable tool in understanding the internal structure of the nucleon and has provided motivation for the standard model of quarks and the concept of asymptotic freedom. When coupled with parity-violating measurements through the interference of a virtual photon and weakly interacting Z boson, new linear combinations of quarks are probed which can provide information which is complementary to the standard electromagnetic interactions. Precision measurements on deuterium allows for novel tests of the standard model, possible observations of quark-level charge symmetry violation, and the study of specific higher-twist effects. Additionally, measurements on a proton target can provide a precise extraction of the parton ratio $d/u$ as the scaling variable $x \rightarrow 1$. Separate experiments have also been approved to measure transverse momentum distributions over a broad kinematic range and $J/\psi$ production cross sections at threshold. Presented will be the approved experimental program at Thomas Jefferson National Accelerator Facility using the Solenoidal Large Intensity Device (SoLID). [Preview Abstract] |
Monday, April 15, 2013 11:45AM - 11:57AM |
Q13.00006: Extraction of Neutron Structure Functions from (Semi)InclusiveDeuteron Data Narbe Kalantarians Structure functions parameterize fundamental information about the internal structure of the nucleon, and in the deep-inelastic region are given in terms of the longitudinal momentum distributions of the nucleons' quark and gluon constituents. Compared to the copious amount of proton structure function data, there is considerably less for the neutron, which is mainly derived from deuteron data. Extracting neutron structure functions from the deuteron results in ambiguities from the necessary nuclear corrections. Such ambiguities can be confronted using free neutron and proton and inclusive deuteron data. The Barely Off-shell Neutron Structure experiment (BoNuS) ran in experimental Hall B at Jefferson Lab in 2005 and provided a virtually free neutron target for the first time. Extraction of the free neutron structure functions has been performed via global fits to both the BoNuS and deuteron inclusive data, utilizing an existing fit to the free proton, within the framework of the weak binding approximation and utilizing various nuclear potentials. We will report on the results of this fitting effort and the consistency between neutron information from BoNuS and the impulse approximation. [Preview Abstract] |
Monday, April 15, 2013 11:57AM - 12:09PM |
Q13.00007: Hybrid model calculation of light flavor asymmetry in the proton sea Mary Alberg Our hybrid model includes both perturbative and non-perturbative contributions to the $\bar{d}$ and $\bar{u}$ distributions in the proton sea. The non-perturbative contribution is described by a meson cloud model which includes a Fock state expansion of the proton in terms of meson-baryon pairs. The perturbative contribution is described by a statistical model which uses Fock states of quarks, antiquarks and gluons to represent the parton distributions of the ``bare'' hadrons in the meson cloud. We compare our results to the E866 data for $\bar{d}(x)-\bar{u}(x)$ and $\bar{d}(x)/\bar{u}(x)$. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700