Polarization-transfer measurement to a large-virtuality bound proton in the deuteron
nucl-ex
/ Authors
A1 Collaboration, I. Yaron, D. Izraeli, P. Achenbach, H. Arenhövel, J. Beričič, R. Böhm, D. Bosnar, L. Debenjak, M. O. Distler
and 21 more authors
A. Esser, I. Friščić, R. Gilman, I. Korover, J. Lichtenstadt, H. Merkel, D. G. Middleton, M. Mihovilovič, U. Müller, E. Piasetzky, S. Širca, S. Strauch, J. Pochodzalla, G. Ron, B. S. Schlimme, M. Schoth, F. Schulz, C. Sfienti, M. Thiel, A. Tyukin, A. Weber
/ Abstract
Possible differences between free and bound protons may be observed in the ratio of polarization-transfer components, $P'_x/P'_z$. We report the measurement of $P'_x/P'_z$, in the $^2\textrm{H}(\vec{e},e^{\prime}\vec{p})n$ reaction at low and high missing momenta. Observed increasing deviation of $P'_x/P'_z$ from that of a free proton as a function of the virtuality, similar to that observed in \hefour, indicates that the effect in nuclei is due to the virtuality of the knock-out proton and not due to the average nuclear density. The measured differences from calculations assuming free-proton form factors ($\sim10\%$), may indicate in-medium modifications.