Study of vector mesons in dimuon production in a large kinematic region in p-W and S-W interactions at 200 GeV/c/nucleon

Results are presented on and production in p–W and S–W interactions at 200 GeV/c/nucleon measured via the dimuon decay in a large kinematic region. The data are normalized to the charged particle multiplicity in the same rapidity interval. They have been collected using the HELIOS/3 muon spectrometer at the CERN SPS. The ratio , where is the relevant resonance branching fraction, increases between proton and sulphur projectiles, and is somewhat enhanced going from peripheral to central S–W interactions. This results from an increase in the number of produced 's per charged particle. The ratio is measured in different intervals of p and rapidity. It is not clearly dependent on p, but is larger at higher rapidities. production, likewise normalized to charged multiplicity, is significantly lower in S–W compared to p–W interactions. Received: 27 October 1997 / Revised version: 5 March 1998 / Published online: 13 July 1998     

Classical microscopic calculation of fast heavy-ion collisions

We consider heavy-ion collisions with beam energies of a few hundred MeV/nucleon, because such collisions seem favorable for producing compressed nuclear matter. As an alternative to hydrodynamic ways of calculating such collisions, we are investigating a microscopic, rapid (and therefore economical) simulation method. There are two simplifications basic to this method: (i) using classical particle kinematics, and (ii) taking nucleonnucleon interactions into account via cross sections rather than explicit forces. Some other simplifications, concerning nuclear binding etc., are presently crude but will be improved. Even at normal density, nuclear matter is not so dilute; therefore our calculations show some sensitivity to details of the mechanism assume for nucleon-nucleon scattering. For head-on collision of two mass-235 nuclei, our present calculations yield maximum densities between 2 and 3 times that of normal nuclear matter.     

Photolysis and Pyrolysis of N-Methyl Isoindole

Near UV. irradiation of N-methyl isoindole ( 1 ) in deaerated solution has yielded two constitutionally isomeric [_π4_s+_π4_s] dimers 3 and 4 (Scheme 2). No transient or stable photoisomers of 1 were detected. The photodimers were reconverted to 1 both by pyrolysis and photolysis. The photocleavage of dimer 3 proceeds (predominantly) by anonadiabatic pathway yielding 1 in its electronic ground state. Prolonged pyrolysis of 1 afforded 11H-indeno [1,2-c]-isoquinoline ( 5 ) as a major product.     

Schnitt- und Zykelgeometrien

Ohne ZusammenfassungHabilitationsschrift Darmstadt 1975.     

Eine Charakteristische Spiegelungseigenschaft hermitescher Quadriken

If is a projective space of dimension 3 and characteristic 2 and a semi ovoid of, then is a non degenerate semi quadric and is of finite dimension, if and only if there exists a perspectivity of order 2 and axish stabilizing, for every hyperplaneh meeting in at least 2 points.     

Inelastische Elektronenstreuung an endlichen Kernen

The response function of a finite nucleus is calculated with the help of perturbation theory. Realistic hard core nucleon-nucleon potentials are used. For theT-matrix elements a Bethe-Goldstone like equation is solved using the method of Kallio and Day. Numerical calculations of the response function are carried out for oxygen.