D. Tarnowski

DEEP-INELASTIC ELECTRON SCATTERING FROM CARBON

Abstract We have measured the deep-inelastic electron scattering from carbon up to and including the Δ-region at 36°, 60°, 90° and 145°. The systematic decomposition of the transverse and longitudinal response functions has been obtained by means of a Rosenbluth-type analysis of the data in the momentum transfer interval 200 MeV/c /s |q| /s 600 MeV/c. A comparison with theoretical calculations which extend over the quasielastic and Δ-peak regions is presented. A reduction of the differences between our data and theory seems obtainable through the introduction of meson-exchange currents, resonant and non-resonant meson production, and the use of the shell model. Our experimental Coulomb sum-rule estimates at higher | q | agree with independent particle model predictions. We compare our results in the vicinity of the Δ-peak with the total absorption cross section for real photons.

Momentum distribution of nucleons in the deuteron from the d(e, e′p)n reaction

Abstract The nucleon momentum distribution in the deuteron has been determined up to 340 MeV/ c by measuring the d(e, e′p)n reaction at an incident electron energy of 500 MeV. The data are well described even above p = 200 MeV / c by the most recent deuteron wave functions, in contrast with previous (e, e′p) and (p, 2p) results.

Deep inelastic electron scattering from 12C

Deep-inelastic electron scattering from 12C was measured at 60°, 90°, 130° and 145° until 560 MeV incident electron energy. Longitudinal-transverse separation was achieved for ¦q2μ¦ < 6 fm−2 and energy-loss ω < 360 MeV. The longitudinal sum rule exhibits 80 % of the strength predicted by single particle model. The measured cross section between the quasi-elastic peak and the free Δ peak is compared to different theoretical models. Mesonic exchange current in proton-neutron pairs seems to play an important role.

Coulomb sum rule on12C

SummaryWe have measured the deep inelastic electron scattering from carbon up to and including the Δ region at 36°, 60°, 90° and 145°. The systematic decomposition of the transverse and longitudinal response functions has been obtained by means of a Rosenbluth-type analysis of the data in the momentum transfer interval 200 MeV/c<|q|<550 MeV/c. A comparison with theoretical calculations which extend over the quasi-elastic and Δ peak regions is presented. A reduction of the differences between our data and theory seems obtainable through the introduction of meson exchange currents, resonant and nonresonant meson production and the use of the shell model. Our experimental Coulomb sum rule estimates at higher |q| agree with independent-particle model predictions.RiassuntoÈ stato misurato lo scattering anelastico profondo degli elettroni dal carbonio fino alla regione della Δ compresa a 36, 60, 90 e 145 gradi. La scomposizione sistematica delle funzioni di risposta trasversali e longitudinali è stata ottenuta mediante un’analisi dei dati del tipo di Rosenbluth nell’intervallo dell’impulso trasferito 200 MeV/c <|q|<550 MeV/c. Si presenta un confronto con calcoli teorici che si estendono nella regione quasi elastica e in quella del picco della Δ. Una riduzione delle differenze tra i nostri dati e la teoria sembra ottenibile mediante l’introduzione di correnti di scambio mesonico, produzione di mesoni risonante e non risonante e l’uso del modello a strati. Le nostre stime sperimentali della regola di somma di Coulomb per |q| maggiore sono in accordo con le previsioni del modello a particelle indipendenti.РезюмеМы измеряем глубоко неупругое рассеяние электронов на углероде вплоть до Δ области при углах 36°, 60°, 90° и 145°. Получено систематическое разложение поперечных и прододьных функций отклика с помощью анализа Розенблута данных в области переданных импульсов 200 МэВ/с <|q|<550 МэВ/с. Проводится сравнение с теоретическими вычислениями, которые охватывают квази-упругую область и область Δ пика. Уменьшение различий между нашими данными и теорией, по-видимому, может быть получено при введении мезонных обменных токов, резонансного и нерезонансного рождения мезонов и использовании оболочечной модели. Наши экспериментальные оценки кулоновского правила сумм при высоких |q| согласуются с предсказаниями модели независимых частиц.