119907461
Parity determination for the new generation of heavy neutral mesons
We consider how best to experimentally determine the parity quantum number of a new heavy neutral meson, including the possibility of exotic ${J}^{\mathrm{PC}}$. Multiquark and gluon bound states can have exotic ${J}^{\mathrm{PC}}$ quantum numbers forbidden to the nonrelativistic $q\overline{q}$ system. If only the existence of easily identifiable two-body hadronic modes is known, it is not possible to establish the parity so an "exotic" meson, $Jg0$, could be misidentified as a "normal" meson. Direction-linear-polarization coefficients, which would identify the parity, are also found to be small for $e\overline{e}\ensuremath{\rightarrow}{1}^{\ensuremath{-}\ensuremath{-}}\ensuremath{\rightarrow}{1}^{\ifmmode\pm\else\textpm\fi{}+}\ensuremath{\gamma},{0}^{\ifmmode\pm\else\textpm\fi{}+}\ensuremath{\gamma}$ with the high-energy photon externally converting into an $e\overline{e}$ pair. However, important parity tests do exist, independent of the polarization state of the decaying particle, which can be used to settle the confusion. These are listed in Sec. III of this paper.
121276027
Consequences of su(3)'' excitation in baryon resonances
11827113
DETERMINATIONS OF P, AND CP, FOR HEAVY MESONS AND TESTS FOR THEIR VIOLATIONS WITHOUT POLARIZATION EXPERIMENTS
Powerful results are tabulated which can be used at modern colliders to make fundamental symmetry tests by analysis of sequential decays of X + V1V2. By generalization of the ty$ parity test which has recently been used to determine the parity of the r|c, the P (or CP) quantum number can always be determined for X of any spin J which decays P (or respectively CP) invariantly into VV or VV where each vector meson decays into two spin-0 bosons, or is (0. P can also always be determined from a mode like K + K °. A neutral spin-0 technipion and an elementary Higgs particle, for instance, can be distinguished by such CP invariant decay modes and by <j>p , <j)J, JT, or i£ sufficiently massive by <f>Z° or JZ° where J/\JJ and Z° go into a lepton-antilepton pair. Generalization to the gZ° and gg decay channels, g = gluon jet, which would be relevant to new resonance physics, for example, at the CERN collider is discussed. There are also very simple tests for possible violations of P, of the combination of C plus isospin, of both P and CP, and of both C and CP. The practicality and state-of-the-art property of the c)><|> parity test /1/ has been recently demonstrated by its use /2/ by the Mark III collaboration at SLAC-SPEAR to determine the parity of the t) . Less than twenty events were needed to measure the dependence of the decay correlation function I((ji) = 1 + 6 cos2<f) on the azimuthal angle <j> between the two <f> -* K+KT decay planes and to show agreement with B = -1 (pseudoscalar), instead of 0 <_ 6 <_ 1 (scalar). This (j)(j) parity test /1/ for a spin-zero particle was proposed by Ngee-Pong Chang and myself in 1978 as an analogue of Yang's parity test /3/ for the ir°. By means of the h'elicity formalism /4/, it was soon elegantly generalized /5/ by Trueman for a decaying X particle of any spin J. In the last few months the test has been extended /6,7/ to other V1V2 decay modes, for X of any spin J, including those of neutral X particles with odd chargeconjugation and those of charged X states. It has also been found that a spin-0 technipion and an elementary Higgs particle can be distinguished by a decay mode like (jxj) or JJ (identical vector mesons), K*°K ° (particle-antiparticle pair), <j)p°, <J)J, JT, or if sufficiently massive by cfiZ or JZO where j/t|i and Z° go into a leptonantilepton pair. In this talk we will summarize these new results, explain what has to be measured, and tabulate what can be learned from analysis of specific V1V2 decay modes. Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:1985229 c2-262 JOURNAL DE PHYSIQUE The advantages of t h i s type of t e s t a r e t h a t it i s r igorous, t h a t t he s ignatures a r e s t r i k i n g , t h a t t he P/CP determination i s independent of t he po la r i za t ion s t a t e of t he decaying X system (and so the t e s t is independent of t he production mechanism), t h a t t he P/CP determination never f a i l s f o r J=0 o r when the re i s a Vlt*.V2 exchange property, and t h a t the t e s t i s normally applicable i n semi-inclusive p roduc t i on experiments s ince many X decay modes y i e ld observed s t a t e s with only charged pa r t i c l e s . We w i l l f i r s t consider t he following sequent ia l decay of an X system of any spin J X + v1 v2 Spin 0 mesons A1, B1, ... In t he X r e s t frame the nine h e l i c i t y amplitudes a r e speci f ied by where X = XI-X2 and @ , @ a r e the polar and azimuthal angles of V l . By Lorentzinvariance t h e general decay co r r e l a t i on funct ion is 161 + Bd(01,02) cos 2$ + Bx(01,02) s i n 2+ where the polar angles el and 82 f o r A 1 and A2 momenta a r e defined /5,6/ a s i n Fig. 1. In pa r t i cu l a r , although the azimuthal angle 4 i s invar iant under Lorentz boosts
120421012
The psion family: Relativistic charmonium
The authors have reported earlier that the spectrum of the psion family suggests a treatment based on an O(4) harmonic-oscillator family with O(4) quantum number M = 0 (equally spaced, mass-squared linear Regge trajectories). This results in the new J/subP//subC/ quantum numbers: 0$sup ++$ for 2.8 GeV/ c$sup 2$; 2$sup ++$, 1$sup -+$, 0$sup ++$ for the 3.4-GeV/c$sup 2$ mass region. All radiative decays are related through a single O(4) coupling S/sub mu//sub nu/ F/sub mu//sub nu/, where S/sub mu//sub nu/ is the internal-space angular-momentum operator. The details of the calculations of radiative transition widths and of the $gamma$$gamma$ angular correlation functions are given. Experimental signatures are discussed and compared with the nonrelativistic charmonium scheme; among others J $Yields$ O (2.8) + $gamma$ and psi ' $Yields$ O (2.8) + $gamma$ are small, being forbidden in the strict O(4) limit. O (2.8) is expected to be narrow like all other psions below the 4.0-GeV/c$sup 2$ region. chi$sub 0$(3.41) and chi$sub 1$(3.49) total widths are expected to be around 630 keV and 185 keV respectively. The missing decays of psi ' could be due to psi ' $Yields$ O + $omega$ ( approx. 32%). (AIP)
14270584
Tau decays beyond the standard model
In a recent paper, 8 semileptonic parameters were defined to specify the most general Lorentz-invariant spin correlation functions for 2-body τ decays. These parameters can be used to search for anomalous Γ L , Γ T polarized-partial widths, for non-CKM-type leptonic CP violation, and for leptonic T FS violation. They can also be used to bound the effective-mass scales A for “new physics” arising from additional Lorentz structures, e.g. from lepton compositeness, tau weak magnetism, weak electricity, or second-class currents. It is emphasized that (i) for these tests “different modes have different merits” and that (ii) the parameters can be measured either by using spin-correlation techniques without polarized beams, or with longitudinally polarized beams.
115882781
Cheng-wu picture applied to gamma p ---> rho0 p and phi p
21292465
The MINOS near detector front end electronics
The Near Detector for the MINOS Experiment at Fermilab is composed of alternating planes of scintillator strips and steel plates, and is read out with 64-channel, multi-anode photomultiplier tubes. The instrumentation uses a custom integrated circuit designed at Fermilab for the front end analog processing, called the QIE. The system can measure single photoelectrons to high precision with a dynamic range of 16 bits. The electronics operates in two modes. It records all events that occur during the 10 /spl mu/s "fast spill" of the beam from the Fermilab Main Injector at a rate of 53 MHz, using a gate from the beamline controls to force data acquisition. The system can also acquire data from cosmic rays that pass through the detector for calibration. In this case, dynode signals from the photomultipliers are used as the trigger, causing digitization and readout of the associated channels. Zero suppression and normalization are done in the front end electronics. The system is "triggerless" in that there is no global hardware trigger. Instead, each event is tagged with a "timestamp", which is used in postprocessing to reconstruct events and discard noise hits. The system of 10,000 channels is now built and installed, and operational at Fermilab. The components of the system are described and preliminary system performance is reported.
120528697
Improved upper limit for photoproduction of psi (3105) near threshold
120266108
CDF Front End Electronics: The Rabbit System
Abstract A new crate-based front end system has been built featuring low cost, compact packaging, fast readout, command capability, 16 bit digitization, and a high degree of redundancy. The crate can contain a variety of instrumentation modules and is designed to be placed near the detector. Remote, special purpose processors direct the data readout. Channel-by-channel pedestal subtraction and threshold comparison in the crate allow the skipping of empty channels. The system is suitable for the readout of a very large number of channels.
17434613
Proton irradiation effects on 2Gb flash memory
We report total ionizing dose and single event effects on 2 Gb Samsung flash memory devices after exposure to 200 MeV protons to various doses up to 83 krad(Si). We characterize observed failures and single event upsets on 22 devices from two different lots. Devices from both lots are robust to greater than 20 krad(Si) although we see evidence for lot-to-lot variation where only one lot appears robust up to about 50 krad(Si). Single event upsets are observed at a relatively low rate and are consistent with single isolated bit flips within registers that transfer bits to and from the flash memory cells.
116758744
Pion dissociation in the nuclear Coulomb field