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Proton propagation in nuclei was studied using the (e,elp ) reaction in the quasifree region. The coincidence (e,elp) cross sections were measured at an electron angle of 50.4" and proton angles of 50. lo, 58.2", 67.9", and 72.9" for I2C, "~1 , 58Ni, and I8'Ta targets at a beam energy of 779.5 MeV. The average outgoing proton energy was 180 MeV. The ratio of the ( e , e l p ) yield to the simultaneously measured (e, e') yield was compared to that calculated in the plane-wave impulse approximation and an experimental transmission defined. These experimental transmissions are considerably larger (a factor of -2 for 1 8 '~a ) than those one would calculate from the free N-N cross sections folded into the nuclear density distribution. A new calculation that includes medium effects (N-N correlations, density dependence of the N-N cross sections and Pauli suppression) accounts for this increase.

We have measured the ratio g& /F& over the range 0.029 ( x ( 0.8 and 1.3 ( Q~( 10 (GeV/c) using deep-inelastic scattering of polarized electrons from polarized ammonia. An evaluation of the integral fo g~(x, Q2) dx at fixed Q2 = 3 (GeV/c)2 yields 0.127~0.004(stat)~0.010(syst), in agreement with previous experiments, but well below the Ellis-Jaffe sum rule prediction of 0.160~0.006. In the quark-parton model, this implies Aq = 0.27~0.10.PACS numbers: 13.60. Hb, 11. 55.Hx, 13.88.+e, 14.20.Dh Measurements of the longitudinal and transverse spindependent structure functions gi(x, Q ) and gq(x, Q ) for deep-inelastic lepton-nucleon scattering have become an increasingly important tool in unraveling the complex structures of the proton and neutron.Of particular interest are the integrals I t (Q ) = f"g (x,tQ )dx the proton and I i (Q ) = ftI gi (x, Q ) dx for the neutron.

The tensor polarization of the recoil deuteron in elastic electron-deuteron scattering has been measured at the Bates Linear Accelerator Center at three values of four-momentum transfer, Q = 3.78, 4.22, and 4.62 fm-', corresponding to incident electron energies of 653, 755, and 853 MeV. The scattered electrons and the recoil deuterons were detected in coincidence. The recoil deuterons were transported to a liquid hydrogen target to undergo a second scattering. The angular distribution of the d-p scattering was measured using a polarimeter. The polarimeter was calibrated in an auxiliary experiment using a polarized deuteron beam at the Laboratoire National Saturne. A Monte Carlo procedure was used to generate interpolated calibration data because the energy spread in the deuteron energies in the Bates experiment spanned the range of deuteron energies in the calibration experiment. The extracted values of tzo are compared to predictions of different theoretical models of the electromagnetic form factors of the deuteron: nonrelativistic and relativistic nucleon-meson dynamics, Skyrme model, quark models, and perturbative quantum chromodynamics. Along with the world data on the structure functions A ( Q ) and B(Q), they are used to separate the charge monopole and charge quadrupole form factors of the deuteron. A node in the charge monopole form factor is observed at Q = 4.39 i 0.16 fm-' .

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