1. 1 Experimental Nuclear Physics at UMass UMass, February 1st, 2010

2. Elastic Electron Scattering (Kumar) Nuclear charge distribution Measure  as a function of Q 2 Neglecting recoil and spin: Obtain Fourier transform of charge distribution Jefferson Laboratory We now know that electrons interact with nuclei also via the weak force Z0Z0  E E’ 4-momentum transfer This is a rare process; tough to isolate: sophisticated measurement technique

3. The PREX Experiment http://hallaweb.jlab.org/parity/prex Neutron star has solid crust over liquid core. Heavy spinless nucleus has neutron skin. Both neutron skin and neutron star crust are made out of neutron rich matter at similar densities. Neutron StarLead Nucleus crustskin R p ~ 5.5 fm R n -R p ~ 0.1 to 0.3 fm? 10 km 10 fm  (A PV ) ~ 3%  (R p -R n ) ~ 1% Q 2 ~ 0.01 GeV 2 A PV ~ 0.5 ppm Construction Ongoing; Data run ~ March-June 2010 Faculty: Krishna Kumar Postdocs: Juliette Mammei, Dustin McNulty Graduate Students: Luis Mercado, Jon Wexler, Sereres Johnston Undergraduates: Patrick Rogan, Kyle Schmoll, Vireak Yim Next Project: The MOLLER Experiment Precision test of the weak force to search for clues about the early universe Complementary to Large Hadron Collider experiments

4. 4 Probing Mysteries in the Spin Structure of the Proton Amaresh Datta, Mikhail Stepanov, Dave Kawall, UMass UMass, February 1st, 2010 http://www.phenix.bnl.gov

5. 5 Probing Mysteries in the Spin Structure of the Proton

6. A.Pocar/K.Kumar - 2/1/10 6 0νββ 2νββ Double beta decay: EXO (Kumar, Pocar) ✦ neutrinos are their own antiparticles ✦ violation of lepton number ✦ measurement of the absolute ν mass ✦ relevant to particle physics and cosmology standard second order weak process   ×10 -2 ×10 -6 sensitivity to ≥10 25 y lifetimes: ✦ ultra-low background ✦ underground location ✦ large source mass extremely rare decay in which a nucleus simultaneously emits two electrons exciting possibility of a non-standard 0 νββ process electron kinetic energy New physics?

7. A.Pocar/K.Kumar - 2/1/10 7 EXO-200: 136 Xe Design sensitivity for 0 νββ lifetime : 6×10 25 years detect the 2 electrons (ionization + scintillation) 136 Xe → 136 Ba ++ + 2e - (+ 2ν e ) 200 kg Xe (80% 136 isotope) time projection chamber (TPC) detector 3D reconstruction of events + energy e- fully commissioned deep underground salt mine in New Mexico (WIPP site) TPC installed in cryostat at WIPP

8. A.Pocar/K.Kumar - 2/1/10 8 EXO at UMass activities: ‣ EXO-200 data analysis (for the coming 4-5 years) ‣ EXO-200 running at WIPP (includes regular shifts WIPP) ‣ EXO-200 calibration campaigns ‣ work on the EXO-200 muon detector ‣ GEANT4 simulations (EXO-200 and future larger EXO experiment) ‣ EXO lab at UMass (for various aspects of EXO R&D): ‣ scintillation detection in LXe and LAr ‣ tagged Ba ion source (Ton-scale EXO R&D) people: Krishna Kumar, Andrea Pocar Tim Daniels - postdoc Peter Morgan, Jessica Cook - grad Chris Sterpka, Kyle Schmoll - ug