The high-intensity hyperon beam at CERN

A high-intensity hyperon beam was constructed at CERN to deliver Sigma- to experiment WA89 at the Omega facility and operated from 1989 to 1994. The setup allowed rapid changeover between hyperon and conventional hadron beam configurations. The beam provided a Sigma-flux of 1.4 x 10^5 per burst at mean momenta between 330 and 345 Gev/c, produced by about 3 x 10^10 protons of 450 GeV/c . At the experiment target the beam had a Sigma-/pi- ratio close to 0.4 and a size of 1.6 x 3.7 cm^2. The beam particle trajectories and their momenta were measured with a scintillating fibre hodoscope in the beam channel and a silicon microstrip detector at the exit of the channel. A fast transition radiation detector was used to identify the pion component of the beam.Comment: 20 pages, 13 figures. Submitted to Nucl. Instr. Meth.

Transverse single-spin asymmetries in gauge boson production

Transverse single-spin asymmetries (SSA) in inclusive reactions are now considered to be directly related to the transverse momentum $k_{T}$ of the fundamental partons involved in the process. Several possible leading-twist QCD mechanisms have been proposed to explain the available data, in particular the Sivers effect which was resurrected recently. We show that from the measurement of transverse SSA in inclusive production of gauge bosons, one can learn more about the Sivers functions and possibly to achieve a reliable flavor separation.Comment: 7 pages, latex, no figures, to be published in Phys.Lett.

Fundamental Symmetries and Interactions - Some Aspects

In the framework of nuclear physics and at nuclear physics facilities a large number of different experiments can be performed which render the possibility to investigate fundamental symmetries and interactions in nature. In particular, the precise measurements of properties of fundamental fermions, searches for new interactions in $\beta$-decays, and violations of discrete symmetries have a robust discovery potential for physics beyond standard theory. Precise measurements of fundamental constants can be carried out as well. Low energy experiments allow probing of New Physics models at mass scales far beyond the reach of present accelerators or such planned for the future in the domain of high energy physics and at which predicted new particles could be produced directly.Comment: Review Talk ENAM'0

Transverse single spin asymmetries in photon production

Transverse single-spin asymmetries (SSA) in inclusive reactions are now considered to be directly related to the transverse momentum ${\bf k}_{T}$ of the fundamental partons involved in the process. We find that the ideal probe to extract information on the gluon Sivers function is the transverse SSA of prompt photon production $p p^{\uparrow} \to \gamma X$, at large $p_T$. The following related processes, $p p^{\uparrow} \to \gamma + jet + X$, $p p^{\uparrow} \to \gamma^* + X \to \mu^+ \mu^- + X$ and $\bar{p} p^{\uparrow} \to \gamma + X$ are also briefly discussed.Comment: 9 pages, 1 figure, to appear Physics Letters

Measurement of Permanent Electric Dipole Moments of Charged Hadrons in Storage Rings

Permanent Electric Dipole Moments (EDMs) of elementary particles violate two fundamental symmetries: time reversal invariance (T) and parity (P). Assuming the CPT theorem this implies CP-violation. The CP-violation of the Standard Model is orders of magnitude too small to be observed experimentally in EDMs in the foreseeable future. It is also way too small to explain the asymmetry in abundance of matter and anti-matter in our universe. Hence, other mechanisms of CP violation outside the realm of the Standard Model are searched for and could result in measurable EDMs. Up to now most of the EDM measurements were done with neutral particles. With new techniques it is now possible to perform dedicated EDM experiments with charged hadrons at storage rings where polarized particles are exposed to an electric field. If an EDM exists the spin vector will experience a torque resulting in change of the original spin direction which can be determined with the help of a polarimeter. Although the principle of the measurement is simple, the smallness of the expected effect makes this a challenging experiment requiring new developments in various experimental areas. Complementary efforts to measure EDMs of proton, deuteron and light nuclei are pursued at Brookhaven National Laboratory and at Forschungszentrum Juelich with an ultimate goal to reach a sensitivity of 10^{-29} e cm.Comment: 8 pages, 2 figure

On the Neutralino as Dark Matter Candidate - II. Direct Detection

Evaluations of the event rates relevant to direct search for dark matter neutralino are presented for a wide range of neutralino masses and for various detector materials of preeminent interest. Differential and total rates are appropriately weighted over the local neutralino density expected on theoretical grounds.Comment: (18 pages plain TeX, 24 figures not included, available from the authors) DFTT-38/9

Elektret- und Piezoelektret-Wandler für Körperschallaufnahme und Energy-Harvesting

In der vorliegenden Arbeit werden Elektret- und Piezoelektret-Wandler hinsichtlich ihrer Eig-nung als Körperschallaufnehmer und Energy-Harvester untersucht. Nach der Einleitung in das Thema werden in Kapitel 1 die Ziele der Arbeit vorgestellt. In Kapitel 2 werden die Grundlagen der Materialien und Wandler präsentiert und die Literatur über Elektrete, Piezoelektrete, Beschleunigungsaufnehmer und Energy-Harvesting analysiert. Zu-nächst werden das Herstellungsverfahren und typische Anwendungen von Elektreten und Pie-zoelektreten vorgestellt. Anschließend wird eine Einführung in die Grundlagen, die unter-schiedlichen Wirkprinzipien, Anwendungen und Charakterisierungsmethoden von Beschleunigungsaufnehmern besprochen. Zum Schluss dieses Kapitels wird auf das Thema Energy-Harvesting eingegangen: Die unterschiedlichen Arten von schwingungsbasierten Energy-Harvestern, die Leistungskonditionierungs- und Charakterisierungsmethoden sowie un-terschiedliche Figures of Merit zum Auswerten von Energy-Harvestern werden vorgestellt. Kapitel 3 befasst sich mit Piezoelektret- und Elektret-Beschleunigungsaufnehmern. Zunächst wird ein analytisches Modell von Piezoelektret-Beschleunigungsaufnehmern mit einem oder mehre-ren Piezoelektretstapeln aus ihrer Bewegungsgleichung hergeleitet. Anschließend werden mo-dale Sensoren und platinenintegrierte Piezoelektret-Beschleunigungsaufnehmer als zwei An-wendungsbeispiele präsentiert. Schließlich wird ein weiteres analytisches Modell, und zwar für Elektret-Beschleunigungsaufnehmer aus der Bewegungsgleichung abgeleitet und auch hier die experimentellen Ergebnisse diskutiert. Kapitel 4 ist Piezoelektret- und Elektret-Energy-Har-vestern gewidmet. Für beide Harvestertypen wird ebenfalls jeweils ein analytisches Modell er-stellt und experimentell validiert. Unter anderem wird die Abhängigkeit der Resonanzfrequenz und der maximalen Leistung von der seismischen Masse analysiert. Im Fall von Piezoelektret-Harvestern mit d33-Effekt wird auch insbesondere der Effekt des Piezoelektretstapels auf die Eigenschaften des Harvesters untersucht. Bei Piezoelektret-Harvestern mit d31-Effekt wird der Einfluss der Kraftwirkung in Richtung des Piezoelektretstreifens auf die Leistung analysiert. Im Fall von Elektret-Harvestern wird der Effekt der mechanischen Eigenschaften des Abstandshal-ters und der Abmessungen des Luftspalts zwischen der seismischen Masse und der Grundelekt-rode auf die maximale Leistung und die Resonanzfrequenz untersucht. Anschließend werden die von den unterschiedlichen Harvestern generierten Leistungen gemessen, anhand von Figu-res of Merit ausgewertet und mit Literaturwerten für piezoelektrische Harvester verglichen. Die Arbeit schließt in Kapitel 5 mit einer Zusammenfassung und einem Ausblick über zukünftige Untersuchungen und Anwendungen von den in der Dissertation vorgestellten Wandlern

Chiral QCD, General QCD Parameterization and Constituent Quark Models

Several recent papers -using effective QCD chiral Lagrangians- reproduced results obtained with the general QCD parameterization (GP). These include the baryon 8+10 mass formula, the octet magnetic moments and the coincidental nature of the "perfect" -3/2 ratio between the magnetic moments of p and n. Although we anticipated that the GP covers the case of chiral treatments, the above results explicitly exemplify this fact. Also we show by the GP that -in any model or theory (chiral or non chiral) reproducing the results of exact QCD- the Franklin (Coleman Glashow) sum rule for the octet magnetic moments must be violated.Comment: 10 pages, Latex; abridged version (same results), removed some reference

On Observing Top Quark Production at the Tevatron

A technique for separating top quark production from Standard Model background events is introduced. It is applicable to the channel in which one top quark decays semi-leptonically and its anti-quark decays hadronically into three jets, or vice versa. The method is shown to discriminate dramatically between Monte Carlo generated events with and without simulated top quarks of mass around 120 GeV and above. The simulations were performed with CDF detector characteristics incorporated, showing that the method is applicable to existing data.Comment: 8 pages, TUFTS-TH-92-G01 (Two minor TeX mistakes corrected

Nonsimultaneous Chains and Dominos in Kidney- Paired Donation—Revisited

Since 2008, kidney exchange in America has grown in part from the incorporation of nondirected donors in transplant chains rather than simple exchanges. It is controversial whether these chains should be performed simultaneously ‘domino-paired donation’, (DPD) or nonsimultaneously ‘nonsimultaneous extended altruistic donor, chains (NEAD). NEAD chains create ‘bridge donors’ whose incompatible recipients receive kidneys before the bridge donor donates, and so risk reneging by bridge donors, but offer the opportunity to create more transplants by overcoming logistical barriers inherent in simultaneous chains. Gentry et al. simulated whether DPD or NEAD chains would produce more transplants when chain segment length was limited to three transplants, and reported that DPD performed at least as well as NEAD chains. As this finding contrasts with the experience of several groups involved in kidney-paired donation, we performed simulations that allowed for longer chain segments and used actual patient data from the Alliance for Paired Donation. When chain segments of 4–6 transplants are allowed in the simulations, NEAD chains produce more transplants than DPD. Our simulations showed not only more transplants as chain length increased, but also that NEAD chains produced more transplants for highly sensitized and blood type O recipients.Alliance for Paired DonationNovartis (Firm)Genzyme CorporationF. Hoffmann-La Roche & Co.Pfizer Inc.Astellas Pharma USNational Science Foundation (U.S.) (Grant No. 0616733 to the National Bureau of Economic Research)Life Connection of OhioUniversity of Toled