Nadia Fomin University of Virginia Inclusive Scattering from Nuclei at x>1 and High Q2 with a 5.75 GeV Beam Nadia Fomin University of Virginia

Physics topics we can study at x>1 Momentum distributions of nucleons inside nuclei Short range correlations (the NN force) 3-Nucleon correlations Comparison of heavy nuclei to LD2 and 3He Scaling (x, y) at large Q2 Constraints on the high momentum tail of the nuclear wave function Structure Function Q2 dependence

Quasielastic scattering: an example (Deuterium)

Electron scattering and x ranges Scattering from a free nucleon: 0<x<1 : x=1 (elastic) x<1 (inelastic) x > 1: momentum is shared between nucleons, so 0<x<A  probing the effect of nuclear medium on quark distributions  kinematics determine whether the electron scatters from quarks or hadrons Regions being probed:  Low Q2 – entire nucleus (elastic)  Intermediate Q2 – single nucleon (Quasielastic Scattering – QES)  Higher Q2 – DIS (“superfast” quarks at x>1) x>1 probes the QES and DIS regions

Y-scaling Introduced by Kawazoe and West in 1975 Scaling function F(y) can be extracted from the measured cross-section if QES is the dominant reaction mechanism F(y) is defined as ratio of the measured cross-section to the off-shell electron-nucleon cross- section times a kinematic factor At large q, neglecting momenta perpendicular to q and using energy conservation In general, F=F(y,Q2), but the Q2 dependence vanishes at high momentum transfer n(k) is the nucleon momentum distribution Scaling breaks down if there are significant Final State Interactions between the struck nucleon and the residual nucleus, but this should also vanish at sufficiently high Q2

Y-Scaling (Example: 3He) y is the momentum of the struck nucleon parallel to the momentum transfer. 0.1<Q2<3.9

E02-019 Details E02-019 is currently running at Jefferson Lab in Hall C E02-019 is an extension of E89-008, but with higher E (5.75 GeV), Q2 , x and y. Cryogenic Targets: LH2, LD2, 3He, 4He Solid Targets: C, Cu, Au. Spectrometers: HMS and SOS

Experimental Setup in Hall C HMS SOS

High Momentum Spectrometer Superconducting magnets in a QQQD configuration Maximum central momentum of 6.0 GeV/c with 0.1% resolution and a momentum bite of ±10% Solid angle of 6.7 msr Detectors 2 sets of Drift chambers 2 sets of x-y hodoscopes Gas Čerenkov detector Lead glass shower counter Pion Rejection of ~75,000 using the Čerenkov and the Lead Glass Shower Counter

Short Orbit Spectrometer For E02-019, the SOS is primarily used to estimate the charge symmetric background. Has a solid angle of 7 msr and a large momentum bite (±20%) Maximum central momentum of 1.75 GeV/c QDD magnet configuration (non-superconducting): Pion Rejection of ~10,000 using the Čerenkov and the Lead Glass Shower Counter Detector Package is very similar to that of HMS

New Frontiers Existing data

3He online spectrum

Summary To date, we’ve taken over 60% of the data This experiment will provide data over an extended kinematic range and significantly improve the 3He and 4He data sets Preliminary results should be ready by next year’s DNP meeting (see you in Hawaii)

E02-019 Collaboration Argonne National Lab California Institute of Technology Hampton University Thomas Jefferson National Accelerator Facility University of Basel (Roman Trojer) University of Virginia

New Frontiers Existing data