A kinematical selection of glueball candidates in central production

A study of central meson production as a function of the difference in transverse momentum ($dP_T$) of the exchanged particles shows that undisputed $q \overline q$ mesons are suppressed at small $dP_T$ whereas the glueball candidates are enhanced

Blue pigmentation of neustonic copepods benefits exploitation of a prey-rich niche at the air-sea boundary

The sea-surface microlayer (SML) at the air-sea interface is a distinct, under-studied habitat compared to the subsurface and copepods, important components of ocean food webs, have developed key adaptations to exploit this niche. By using automated SML sampling, high-throughput sequencing and unmanned aerial vehicles, we report on the distribution and abundance of pontellid copepods in relation to the unique biophysicochemical signature of the SML. We found copepods in the SML even during high exposure to sun-derived ultraviolet radiation and their abundance was significantly correlated to increased algal biomass. We additionally investigated the significance of the pontellids’ blue pigmentation and found that the reflectance peak of the blue pigment matched the water-leaving spectral radiance of the ocean surface. This feature could reduce high visibility at the air-sea boundary and potentially provide camouflage of copepods from their predators

THE SLOW POSITION-SENSITIVE TIME-OF-FLIGHT DETECTOR OF THE GAMS NA 12/2 EXPERIMENT OF CERN

A large time-of-flight detector has been built by the GAMS NA12/2 experiment at CERN. It surrounds a 60 cm long liquid hydrogen target. With a time resolution better than sigma = 350 ps, pion/proton separation is achieved up to a 800 MeV/c momentum

A study of the f(0)(1370), f(0)(1500), f(0)(2000) and f(2)(1950) observed in the centrally produced 4 pi final states

{The production and decay properties of the f(0)(1370), f(0)(1500), f(0)(2000) and f(2)(1950) have been studied in central pp interactions at 450 GeV/c. The dP(T), phi and \textbackslash{}t\textbackslash{} distributions of these resonances are presented. For the J= 0 states, the f(0)(1370) and f(0)(2000) have similar dP(T) and phi dependences. These are different to the dP(T) and phi dependences of the f(0)(980), f(0)(1500) and f(0)(1710). For the J = 2 states the f(2)(1950) has different dependences to the f(2)(1270) and f(2)(1520). This shows that the dP(T) and phi dependences are not just J phenomena. (C) 2000 Published by Elsevier Science B,V. All rights reserved.

A study of the eta eta ` and eta `eta ` channels produced in central pp interactions at 450 GeV/c

The reactions pp –> p(f)(X-0)p(s), where X-0 is observed decaying to eta eta’ and eta’eta’, have been studied at 450 GeV/c. This is the first time that these channels have been observed in central production and only the second time that the eta’eta’ channel has been observed in any production mechanism. In the eta eta’ channel there is evidence for the f(0)(1500) and a peak at 1.95 GeV. The eta’eta’ channel shows a peak at threshold which is compatible with having J(PC) = 2(++) and spin projection J(Z) = 0. (C) 2000 Published by Elsevier Science B.V. All rights reserved