Inclusive pion production at large transverse momenta in pp collisions is studied in the framework of partonparton scattering with partons carrying transverse momentum and with quark and giuon distributions determined from exact requirements of quantum chromodynamics. CERN ISR data are fairly well accounted for, but Fermilab data somewhat exceed the predictions. Gluon effects are considered in detail. * *K~~, K~~ has already been considered. We follow essentially the notation of Ref. 27, take wz, = m b = m , wzc=md = 0 , and s e t

A general method for constructing a generating function for all irreducible polynomial tensors, with respect to a given compact semisimple group, out of a given set of tensors is derived. The method is applied to the construction of polynomial bases for the IR’s of a group reduced according to a subgroup and to the finding of subgroup scalars in the enveloping algebra of a group. A number of examples are worked out.

No abstract

Freestanding micrometer thick graphene oxide (GO) membranes combine high stiffness, low mass density, and high loss coefficient. This unique combination of properties is ideal for efficient and broadband electro‐acoustic transduction, relying on membrane lightness, stiffness, and internal damping. Here, the viscoelastic response of GO membranes is measured, and the application of ≈100 µm thick GO membranes is demonstrated in dynamic loudspeakers. Using dynamic mechanical analysis and the time‐temperature superposition principle of polymer rheology, it is found that the stiffness of GO membrane increases by more than 50% over 1–20 kHz while damping decreases by less than 20%. GO membranes exhibit 45% higher damping than aluminum membranes in loudspeakers assemblies. Consequently, GO membranes enable the upshift of loudspeaker breakup frequency by 16 to 12 octave above speakers assembled with aluminum, polyethylene terephthalate, titanium, and oak wood membranes. GO is thus found to be an exceptional material for electro‐acoustic transduction.

The grand partition function of hadronic bremsstrahlung is obtained using saddle-point procedures. Several levels of' approximation are considered. The results are qualitatively consistent with earlier simple approximations.