J. Lieb

Search for η-mesic nuclei in a recoil-free transfer reaction

We have studied the reaction p+{sup 27}Al {yields} {sup 3}He+p+{pi}{sup -}+X at recoil-free kinematics. An {eta} meson possibly produced in this reaction would be thus almost at rest in the laboratory system and could therefore be bound with high probability, if nuclear {eta} states exist. The decay of such a state through the N*(1535) resonance would lead to a proton-{pi}{sup -} pair emitted in opposite directions. For these conditions we find some indication of such a bound state. An upper limit of {approx_equal}0.5 nb is found.

Simultaneous measurements of the p+d→(A=3)+π reactions

A stack of annular detectors made of high purity germanium was used to measure simultaneously

Magnetic spectrometer Big Karl for studies of meson production reactions

pd\to {^3H} \pi^+

Cross section and tensor analysing power of the dd→ηα reaction near threshold

and

Detailed comparison of the pp→π+pn and pp→π+d reactions at 951 MeV

pd\to {^3He} \pi^0

Experimental study of the p + 6Li → η + 7Be reaction 11.3 MeV above threshold

differential cross sections at beam momenta of 750 MeV/c, 800 MeV/c, and 850 MeV/c over a large angular range. The extracted total cross sections for the

Precision measurements of the pp ->pi(+)pn and pp ->pi(+)d reactions: Importance of long-range and tensor force effects

pd\to {^3He} \pi^0

Differential cross section measurement for the pp -> d(pi)+ reaction at 850 MeV/c

reactions bridge a gap between near threshold data and those in the resonance region. The ratio of the cross sections for the two reaction channels taken at the same

SEARCH FOR η-NUCLEUS BOUND STATE AT COSY

\eta={p^{cm}_\pi}/m_\pi

Study of p + d → 3A + π reactions in the Δ-resonance region

yields