Three structure functions have been determined in the reaction O(e, e'p) N at Q = 0.20 (GeV/c) for 1p~l2 and 1psI2 knockout and for the excitation of the (5/2+, 1/2+) doublet at E = 5.3 MeV in N. The longitudinal-transverse interference structure function WL,~is enhanced by a factor 2.05 + 0.06 + 0.12 for 1p3/z knockout and by a factor 1.50 + 0.10 + 0.08 for 1pq/q knockout with respect to a calculation that gives a proper account of data taken in parallel kinematics. The longitudinal structure function Wl. is also enhanced, albeit less with respect to these calculations. PACS number(s): 25.30. Fj, 27.20.+n ExperiInents involving the electron-induced protonknockout reaction are commonly used to study proton momentum distributions in atomic nuclei [1, 2]. In most cases these experiments comprise cross-section measurements only. More information on various aspects of the (e, e'p) reaction, such as the basic electron-proton coupling or the final-state interaction, can be obtained by studying the four structure functions that are contained in the (e, e p) cross section. By combining cross sections measured under difFerent kinematical conditions one can isolate these structure functions, and thus reveal efFects that may not be easily observable in the cross section. A few experiments involving a separation of the longitu-I dinal and transverse structure functions have been performed in kinematics with the recoil proton and virtualphoton momentum vectors parallel [3]. For transitions to final states below the two-particle emission threshold these experiments generally confirm the validity of the impulse approximation. In this paper we present the results of an (e, e'p) experiment on 0, in which all three in-plane structure functions have been measured. In previous sO(e, e'p) experiments [4, 5] not all in-plane structure functions have been extracted. In the one-photon-exchange approximation the cross section for the (e, e'p) reaction is expressed as follows [6]: 0 -It oMott (vLWL + vTWT + vLTWLT cos p + vTTWTT cos 2cjk),where IVI"WT, RI,T, and WTT represent the longitudinal, transverse, and interference structure functions, and the electron kinematical factors are given by vL, --$, vT = tan'e. /2 -~' "vLT =~tan'0. /2 -$, and vTT --», with 0, the electron-scattering an-@2 2+2 1 gle, q and u the momentum and energy transfer, and I Q = toq . In Eq. (1), K =~z , is a kinematical factor and 0M tt is the cross section for elastic scattering ofF a point charge. Finally, P represents the angle between the electron-scattering plane and the plane defined by the momentum transfer q and the outgoing proton momentum p . If these planes coincide, the kinematics is labeled "in plane. " The structure functions can be separated by "Present address:The Netherlands.performing measurements with difFerent kinematical factors v and/or values of P, while keeping q and to constant. For the separation of t/VL, T in an in-plane experiment, two measurements at constant p =~0 & -0~~a re required: one at 0&I ( 0~corresponding to P = 0' and the o...

In the four-momentum-transfer range 0.05 <^v 2 < 0.27 (GeV/c) 2 , longitudinal and transverse response functions have been determined by performing a Rosenbluth separation of 2 H(e,e'p) coincidence cross sections measured in parallel kinematics. The results are compared to nonrelativistic calculations that include the effects of final-state interaction, meson-exchange currents, and isobar configurations, and to relativistic calculations that include the effects of final-state interaction. The ratios of the response functions agree with both calculations; the absolute values are (16 ± 3 ± 8)% larger than predicted.PACS numbers: 25.30.Fj, 25.10,+s, The deuteron system plays an essential role in nuclear physics as this bound two-nucleon system contributes to the basis of our understanding of the nucleon-nucleon interaction, being the microscopic input for any fundamental model of heavier nuclei. In the theoretical calculations of the two-nucleon system the state of the art is such that experiments with high precision are important to enable comparisons with theoretical predictions and possibly distinguish between the various calculations. The level of our understanding of the two-nucleon system is illustrated by the reasonable description of many existing electron-scattering data. 1 " 3 Only a limited set of high-precision exclusive experiments exists. In particular, no exclusive experiments aimed at separating individual structure functions of the deuteron in the quasielastic domain have been reported so far. Given its general interest, it is of relevance to obtain such precise exclusive data on the deuterium electrodisintegration process. These data should preferably involve the coincident (e.e'p) reaction as it gives access to four independent observables (if no polarization degrees of freedom are considered).In the past, several inclusive quasielastic (QE) electron-scattering experiments have been performed on the deuteron. Nonrelativistic calculations show good agreement with the separated inclusive longitudinal and transverse response functions 4 in the three-momentumtransfer range between 300 and 500 MeV/c. In exclusive experiments the cross sections are measured over a large missing-momentum range, 5,6 and are rather well reproduced by nonrelativistic calculations. In this paper we present the results of an exclusive 2 H(e,e'p) experiment, in which both the longitudinal and transverse response functions have been determined.The description of the QE (e,e'p) process is generally based on the following assumptions: (i) A simple virtual photon is involved in the knockout process (one-photonexchange approximation); (ii) the energy and momentum that the electron loses in the scattering process are transferred to a single nucleon (quasielastic-scattering process); (iii) for the nucleon current the free-nucleon current is taken, modified for off-shell effects [impulse approximation (IA)]. In order to investigate the validity of these assumptions, experiments have been performed on several nuclei, e.g., 4 He (Refs. ...

The interference structure function /oi, the transverse structure function /n, and the longitudinal structure function /oo have been determined in a 2 H(e,e'p) experiment at a four-momentum transfer (? =0.21 (GeV/c) 2 . The/oo and/n data are in agreement both with a nonrelativistic calculation that includes the effects of final-state interaction (FSI), meson-exchange currents, and isobar configurations, and with a relativistic calculation that only includes FSI effects. The/oi data demonstrate the relevance of a relativistic approach even at this low value of the momentum transfer.

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