Volume 163B,number 5,6 PHYSCISLETTERS 28 November1985 DEUTERON ELECTRODISINTEGRATION WITH KAON PRODUCTION Stuan S. HSIAO and Stephen R. COTANCH Department of Phystcs, North Carohna State UnwerstW, Raleigh, NC 27695-8202, USA Receaved17 May 1985 Cross sect:ons for the d(e, e' K +)A n and p(e, e'K +)A reactions are calculated m a relatlvlsuc framework for different sets of amphtudes obtmned from a photoproduction (yp ~ K + A) analysis Elementary electroproductlon measurements favor one set and adjusting the poorly known kaon electromagnetic form factor provides a reasonable descnpt~on of the data Coincident count rates documenting the experimental feaslbthty of Inclusive d(e, e'K + ) A n measurements are presented along with a study assessing the uncertmnty of the entire calculation The utlhty of this reaction for investigating final state KN, AN interactions and possible strange baryon, chbaryon resonances is d~scussed The electron and K + meson are effective nuclear structure probes primarily because their interactions are reasonably well understood and amenable to first-order, stmpllfied theoretical treatments. In kaon electromagnetic production, (y, K ÷) and (e, e'K÷), these two mildly perturba- t~ve interactions are combined, along w~th the novelty of strangeness exchange, to provade an attractive method for studying both nuclei and hyperuuclel. As detmled elsewhere [1-4], measure- ments of this reaction will faclhtate new and improved understanding of the many-baryon systems. Further, such experiments also offer umque prospects for exarmmng the elementary KN and AN interactions, especially for nuclei with established wavefunct~ons. The thrust of the current work [5] ~s to address the latter posslblhty using the simplest nucleus, the deuteron. We begin with a brief discussion and simple phenomenologtcal analys~s of the elementary process e + p ~ e' + A + K +. The amphtudes describing thts reaction prowde a suitable starting point for relatlvlsuc tmpulse approxtmat~on pre- dictions of production from nuclei Following the notauon of ref. [2] the transition matrix element T, in the wrtual one-photon exchange approxtma- tion, is specified by T = e~. J~', (1) for # = 0,1, 2, 3. Here ~ = ~( po,) ~u( po)/p~ (2) is the photon's polanzalaon four-vector deterrmned from the electron current and photon propagator 2__ 2 2 pv - Ev - kv (Px = (E, k) is four-momentum of particle x) whtle J~' = (AKIf~'IN) (3) is the matrix element of the electromagnetic ^ current operator J~ between hadromc physical states D~rac spinors and matrices are represented by u(p) and y~ = (%, 7) respectively. Tlus current, and therefore the T matrix, can be further expressed In terms of stx spin-mdependent, gauge and Lorentz lnvanant amphtudes A, and six known, covanant matrices Jr, T= ra(pA) EA,~gC,u( pN) (4) ! As detatled in our prewous photoproduction study [2], we have computed the elementary amplitudes A, from the five lowest-order Feynman chagrams involving s and u channel exchange baryons (p, A, and ~ 0) as well as t channel exchange mesons (K and K*). The electroproductlon cross secuon is computed using the photon density matrix formulation [6]. Both transverse and longitudinal virtual photon contributions are included and the electromagnetic current is ngorously conserved. 300 0370-2693/85/$ 03.30 © Elsewer Science Pubhshers B.V. (North-Holland Physics Publishmg Division)