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At the quark level there are basically two types of contributions of R-parity violating supersymmetry (Rep SUSY) to neutrinoless double beta decay: the short-range contribution involving only heavy virtual superpartners and the long-range one with the virtual squark and neutrino. Hadronization of the effective operators, corresponding to these two types of contributions, may in general involve virtual pions in addition to close on-mass-shell nucleons. From the previous studies it is known that the short-range contribution is dominated by the pion exchange. In the present paper we show that this is also true for the long-range Rep SUSY contribution. Therefore, we conclude that the Rep SUSY contributes to the neutrinoless double beta decay dominantly via charged pion exchange between the decaying nucleons.

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This report discusses the following topics: study of Z{sup 0} decays; QCD; new particles; Higgs bosons; and forward hadron calorimeter system.

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\\lhcb is one of the four major experiments at the Large Hadron Collider (\\lhc) at CERN. It is custom built to look for CP violation and New Physics in rare decays of heavy flavour hadrons, like the B and D systems. Rare decays that occur via loop diagrams provide a way to probe New Physics at energy scales much higher than can be probed by direct production in experiments. In this article, the \\lhcb prospects for such measurements with exclusive decays of the type $B \\to \\Xs \\gamma$ and $B \\to X_{s} l^{+} l^{-}$ are presented.

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Using data collected with the BESII detector at $e^{+}e^{-}$ storage ring Beijing Electron Positron Collider, the measurements of relative branching fractions for seven Cabibbo suppressed hadronic weak decays $D^0 \\to K^- K^+$, $\\pi^+ \\pi^-$, $K^- K^+ \\pi^+ \\pi^-$ and $\\pi^+ \\pi^+ \\pi^- \\pi^-$, $D^+ \\to \\bar{K^0} K^+$, $K^- K^+ \\pi^+$ and $\\pi^- \\pi^+ \\pi^+$ are presented.

CERN Document Server

We consider the possibility of "Higgs counterfeits" - scalars that can be produced with cross sections comparable to the SM Higgs, and which decay with identical relative observable branching ratios, but which are nonetheless not responsible for electroweak symmetry breaking. We also consider a related scenario involving "Higgs friends," fields similarly produced through gg fusion processes, which would be discovered through diboson channels WW, ZZ, gamma gamma, or even gamma Z, potentially with larger cross sections times branching ratios than for the Higgs. The discovery of either a Higgs friend or a Higgs counterfeit, rather than directly pointing towards the origin of the weak scale, would indicate the presence of new colored fields necessary for the sizable production cross section (and possibly new colorless but electroweakly charged states as well, in the case of the diboson decays of a Higgs friend). These particles ...

CERN Document Server

We review the progress on experimental studies of the non-$D\\bar D$ decays of the $\\psi(3770)$ resonance. With the world average of the observed cross sections for $D\\bar D$ production measured at 3.773 GeV by the MARK-I, MARK-II, BES and CLEO Collaborations, combined together with the cross section for $\\psi(3770)$ production at its peak as well as initial state radiative correction factor, we find that the non-$D\\bar D$ branching fraction of $\\psi(3770)$ decays is $B[\\psi(3770)\\to {\\rm non}-D\\bar D]=(19.8\\pm 1.8 \\pm 5.6)%$, which is consistent within error with $B[\\psi(3770)\\to {\\rm non}-D\\bar D]=(14.7\\pm 3.2)%$ measured previously by the BES Collaboration. In addition, a global amplitude analysis of the cross sections for $e^+e^- \\to {\\rm LH}$ (LH= light hadron) measured by the CLEO Collaboration shows that the light hadron branching fraction of $\\psi(3770)$ ...

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There are some indications from recent determinations of the strong coupling constant alpha_s and the gluon condensate that the Operator Product Expansion may not be accurate enough to describe non-perturbative effects in hadronic tau decays. This breakdown of the Operator Product Expansion is usually referred to as being due to"Duality Violations." With the help of a physically motivated model, we investigate these duality violations. Based on this model, we argue how they may introduce a non-negligible systematic error in the current analysis, which employs finite-energy sum rules with pinched weights. In particular, this systematic effect might affect the precision determination of alpha_s from tau decays. With a view to a possible future application to real data, we present an alternative method for determining the OPE coefficients that might help estimating, and possibly even reducing, this systematic ...

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$\\gamma/\\phi_3$ at hadron colliders

CERN Document Server

This Resource Letter provides a guide to the literature on Quantum Chromodynamics (QCD), the relativistic quantum field theory of the strong interactions. Journal articles, books, and other documents are cited for the following topics: quarks and color, the parton model, Yang-Mills theory, experimental evidence for color, QCD as a color gauge theory, asymptotic freedom, QCD for heavy hadrons, QCD on the lattice, the QCD vacuum, pictures of quark confinement, early and modern applications of perturbative QCD, the determination of the strong coupling and quark masses, QCD and the hadron spectrum, hadron decays, the quark-gluon plasma, the strong nuclear interaction, and QCD's role in nuclear physics. The letter {E} after an item indicates elementary level or material of general interest to persons becoming informed in the field. The letter {I}, for intermediate level, indicates material of a somewhat more ...

CERN Document Server

Measurements of branching fractions and CP-asymmetries of B^{-} \\rightarrow D^{0}K^{-} modes allow a theoretically-clean extraction of the CKM angle \\gamma. The method proposed by Atwood, Dunietz and Soni (ADS) makes use of a decay chain where color and Cabibbo suppression interfere, which produces large CP-violating asymmetries. The CDF experiment reports the first measurement at a hadron collider of branching fractions and CP-asymmetries of suppressed B^{-} \\rightarrow D^{0}h^{-} signals, where h is \\pi or K. Using 5.0 fb^{-1} of data we found a combined significance exceeding 5\\sigma and we determined the ADS parameters with accuracy comparable with B-factories.

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An electroweak singlet scalar can couple to pairs of vector bosons through loop-induced dimension five operators. Compared to a Standard Model Higgs boson, the singlet decay widths in the diphotons and Z gamma channels are generically enhanced, while decays into massive final states like WW and ZZ are kinematically disfavored. The overall event rates into gamma gamma and Z gamma can exceed the Standard Model expectations by orders of magnitude. Such a singlet may appear as a resonant signal in the gamma gamma and Z gamma channels, even with a mass above the WW kinematic threshold.

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In this paper we discuss possible signatures for the production of scalar t_1t_1"* (top squarkonium) bound states #sigma#_t_1 at hadron colliders, where t_1 is the lighter scalar top eigenstate. We first study the decay of #sigma#_t_1; explicit expressions are given for all potentially important decay modes. If t_1 has unsuppressed two-body decays, they will always overwhelm the annihilation decays of #sigma#_t_1. Among the latter, we find that usually either the gg or hh final state dominates, depending on the size of the off-diagonal entry of the top squark mass matrix; h is the lighter neutral scalar Higgs boson of the minimal supersymmetric model. If m_#sigma#_t happens to be close to the mass of one of the neutral scalar Higgs bosons, Q bar Q final states dominate (Q=b or t). W"+W"- and ZZ final states are subdominant. We argue that #sigma#_t_1#->##gamma##gamma# ...

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We investigate the possibility of observing strong interactions of longitudinally polarized weak vector bosons in the process {gamma}{gamma} {yields} ZZ at a photon linear collider. We make use of polarization of the photon beams and cuts on the decay products of the Z bosons to enhance the signal relative to the background of transversely polarized ZZ pairs. We find that the background overwhelms the signal unless there are strong resonant effects, as for instance from a technicolor analogue of the hadronic f{sub 2}(1270) meson.

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The success of the Randall-Sundrum scenario relies on stabilization of the modulus field or the radion, which is the scalar field about the background geometry. The stabilization mechanism proposed by Goldberger and Wise has the consequence that this radion is lighter than the graviton Kaluza-Klein states so that the first particle to be discovered is the radion. In this work, we study in detail the decay, production, and detection of the radion at hadronic, e{sup +}e{sup -}, and {gamma}{gamma} colliders.

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The status of Monte Carlo system for the simulation of Bremsstrahlung in arbitrary decays and for the decay itself of #tau# -lepton is reviewed. During the last #tau# -lepton conference in 2010 several developments of the last two years have been presented: (i) For the TAUOLA Monte Carlo generator of #tau# -lepton decays, automated and simultaneous use of many versions of form-factors for the calculation of optional weights for fits was developed and checked to work in Belle and BaBar software environment. On-going work on alternative parameterizations of hadronic decays is presented too. (ii) The TAUOLA universal interface based on HepMC (the C++ event record) is now public. A similar interface for PHOTOS is now also public. (iii) Extension of PHOTOS Monte Carlo for QED Bremsstrahlung in decays featuring kernels based on complete first order matrix element are ...

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No abstract prepared.

CERN Document Server

We study neutral and charged Higgs boson production in association with stop and sbottom squarks at the Large Hadron Collider, within the supergravity inspired minimal supersymmetric standard model We study neutral and charged Higgs boson production in association with stop and sbottom squarks at the Large Hadron Collider, within the Supergravity inspired Minimal Supersymmetric Standard Model. The phenomenological relevance of such reactions is twofold. Firstly, they constitute a novel production mechanism of Higgs particles, either through a decay of a heavier (anti)squark into a lighter one or via a Higgs bremsstrahlung process. Secondly, their production rates are extremely sensitive to the values assumed by the five input parameters of the model, this possibly allowing one to put stringent constraints on the latter. After an exhaustive scan of the parameter space, we find that the majority of such processes could be ...

CERN Document Server

First measurements of inclusive Z production cross sections in muon and electron decay channels at 7 TeV are presented for proton-proton collisions in the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). The comparison of the kinematic quantities as well as the studies of selection efficiencies demonstrate a good agreement between simulated events and current data. The measured inclusive cross section for Z($\\gamma^{*}$) production agrees with NNLO QCD cross section calculations and current parton distribution functions.

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The geodesic equation for space-like objects moving along a circular trajectory in the expanding universe is considered. Our analysis leads to the conclusion that ancient cosmological tachyons may exist in the present-day world and may play an important role in (i) the internal structure of hadrons conceived as nonlocal objects called strings, (ii) the T-symmetry violation observed in the weak K-decays, (iii) the multidimensional unified field theories of Kaluza-Klein type, and in (iv) the classical models of charged particles which combine ordinary electromagnetism with a self-interacting version of Newtonian gravity. 18 refs.

CERN Document Server

We compute QCD corrections to the production of a ttbar pair in association with a hard photon at the Tevatron and the LHC. This process allows a direct measurement of the top quark electromagnetic couplings that, at the moment, are only loosely constrained. We include top quark decays, treating them in the narrow width approximation, and retain spin correlations of final-state particles. Photon radiation off top quark decay products is included in our calculation and yields a significant contribution to the cross-section. We study next-to-leading order QCD corrections to the ppbar -> ttbar+gamma process at the Tevatron for the selection criteria used in a recent measurement by the CDF collaboration. We also discuss the impact of QCD corrections to the pp -> ttbar+gamma process on the measurement of the top quark electric charge at the 14 TeV LHC.

CERN Document Server

We suggest that \\psi (4040) and \\psi (4160) are strong mixtures of ground state hybrid charmonium at \\sim 4.1 GeV and the \\psi (3S) of conventional charmonium. The \\Gamma^{e^+e^-}, masses and total widths of the \\psi(4040) and \\psi(4160) are in accord with this hypothesis. Their hadronic decays are predicted to be dominated by the \\psi (3S) component and hence are correlated. In particular we find a spin counting relation \\Gamma (4160 \\rightarrow D_sD_s^*) \\sim 4 \\Gamma (4040 \\rightarrow D_sD_s) due to their common \\psi(3S) component. For D and D^* production, using \\psi(4040) branching ratios as input, we predict that the decay pattern of the \\psi(4160) will be very different from that of the \\psi(4040). These predictions may be tested in historical data from SPEAR, BES or at future Tau-Charm Factories.

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Precise measurements of the top quark decay properties at hadron colliders offer interesting new possibilities of testing the standard model. At the same time, recent intriguing experimental results concerning CP violation in the B_d and B_s systems have stimulated many studies of physics beyond the standard model. We investigate anomalous t W d_j interactions as a possible source of new effects in B_{d,s} - bar B_{d,s} oscillations within a model independent approach based on the assumptions of Minimal Flavor Violation. After matching our effective operators onto the low-energy effective Lagrangian describing B_{d,s} meson mixing and evolving it down to the B-mass scale, we extract the preferred ranges of the anomalous t W d_j interactions at the weak scale. These values are then compared to previously considered constraints coming from the rare radiative B --> X_s gamma decay. Finally, we reconsider the associated ...

CERN Document Server

The presented results are the first measurements at RHIC for direct $\\gamma$-charged hadron azimuthal correlations in heavy ion collisions. We use these correlations to study the color charge density of the medium through the medium-induced modification of high-p$_T$ parton fragmentation. Azimuthal correlations of direct photons at high transverse energy (8 $<$ p$_T$ $<$ 16 GeV) with away-side charged hadrons of transverse momentum (3 $<$ p$_T$ $<$ 6 GeV/c) have been measured over a broad range of centrality for $Au+Au$ collisions and $p+p$ collisions at $\\sqrt{s_{NN}}$ = 200 GeV in the STAR experiment. A transverse shower shape analysis in the STAR Barrel Electromagnetic Calorimeter Shower Maximum Detector is used to discriminate between the direct photons and photons from the decays of high p$_T$ $\\pi^{0}$. The per-trigger away-side yield of direct $\\gamma$ is smaller than from $\\pi^{0}$ trigger at the ...

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A distinct feature of Coulomb gauge QCD is that it can be formulated in terms of physical, transverse gluons and quarks alone. The state-counting is then transparent, and the gauge is suited for studies of the excited spectrum. Leaving aside exotic spectroscopy, which has been the subject of other publications, in this note I call attention on two recent applications. One is that the running quark mass in the mid-infrared can be probed from excited baryons thanks to parity doubling, a consequence of insensitivity to chiral symmetry breaking. Fast quarks are asymptotically free and behave as massless, so hadrons containing fast quarks decouple from the condensate. Their (power-law) rate of decoupling reflects on the rate of decreasing parity splittings, which can be measured. The second is that, in analogy with the Franck-Condon principle of molecular physics, the velocity distribution of the heavy quarks inside a heavy hadron can be mapped out ...

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Associated production of a baryonic Z' boson with the W boson can account for the excess in Wjj production observed by the CDF collaboration at the Tevatron. We analyze other possible channels of this Z' at the Tevatron and at the LHC, including \\gamma Z' and Z Z' with the Z' -> jj. We show that the chances of confirming this baryonic Z' is better at the Tevatron than at the LHC because of the faster growing backgrounds at the LHC. Unfortunately the current systematic uncertainties of the order of 10% cannot yield any significant excess in both \\gamma Z' and Z Z' channels at the Tevatron and also at the LHC. Nevertheless the search using the b\\bar b decay mode of Z' is much more feasible at the LHC, provided that the branching ratio B(Z' -> b\\bar b) > 0.1. In particular, the W Z' -> l \

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Quark-hadron duality addresses some of the most fundamental issues in strong interaction physics, in particular the nature of the transition from the perturbative to non-perturbative regions of QCD. I summarize recent developments in quark-hadron duality in lepton-hadron scattering, and outline how duality can be studied at future high-luminosity facilities such as Jefferson Lab at 12 GeV, or an electron-hadron collider such as EPIC.

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Over the last several years considerable concern has been expressed regarding the potential detrimental effects of radon and radon progeny on our health. The complex nature of the radon decay scheme, which involves the emission of a variety of radiations including several [alpha] particles, [beta] particles, and [gamma]-rays, does not lend itself to clear delineation of the biological effects of the [alpha] particles alone. Polonium-210, the terminal radionuclide of the radon decay series, is useful for this purpose because it has a relatively long shelf-life ([tau][sub 1/2] = 138 d), and it only emits a single 5.3 MeV [alpha] particle in its decay to stable [sup 206]Pb. Accordingly, it has been used extensively in radiobiological studies with incorporated radionuclides. The radionuclide [sup 210]Po is produced in a reactor from [sup 209]Bi. (Author).

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We study neutral and charged Higgs boson production in association with stop and sbottom squarks at the Large Hadron Collider (LHC), within the so-called M-SUGRA scenario, i.e., the Supergravity (SUGRA) inspired Minimal Supersymmetric Standard Model (MSSM). For low values of \\tan\\beta only the cases \\tilde{t}_1\\tilde{t}_1^* H, \\tilde{t}_1\\tilde{t}_1^* h and than 30 a variety of signals involving all Higgs bosons can be accessed, at high collider luminosity. The dependence of these reactions on the M-SUGRA parameters might further allow one to pin down the actual structure of the underlying Supersymmetric (SUSY) model.

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The quenched chiral logarithms are examined on a 163x28 lattice with Iwasaki gauge action and overlap fermions. The pion decay constant fpi is used to set the lattice spacing, a = 0.200(3) fm. With pion mass as low as #approx#180 MeV, we see the quenched chiral logarithms clearly in mpi2/m and fP, the pseudoscalar decay constant. The authors analyze the data to determine how low the pion mass needs to be in order for the quenched one-loop chiral perturbation theory (chiPT) to apply. With the constrained curve-fitting method, they are able to extract the quenched chiral logarithmic parameter delta together with other low-energy parameters. Only for mpi<=300 MeV do we obtain a consistent and stable fit with a constant delta which they determine to be 0.24(3)(4) (at the chiral scale Lambdachi = 0.8 GeV). By comparing to the 123x28 lattice, they estimate the finite volume effect to be about 2.7% for the smallest pion mass. They also fitted the ...

CERN Document Server

A historical summary is made on the measurements concerning the rising total hadron-hadron cross sections at high energies. The first part of this paper concerns the total cross section measurements performed at the Brookhaven, Serpukhov and Fermilab fixed target accelerators; then the measurements at the CERN Intersecting Storage Rings (ISR), and at the CERN and at the Tevatron Fermilab proton-antiproton colliders; finally the cosmic ray measurements at even higher energies. A short discussion on Conclusions and Perspectives follows.

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Wonderful opportunities await particle physics over the next decade, with the coming of the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. Here I have in mind the work of the B factories and the Tevatron collider on CP violation and the weak interactions of the b quark; the wonderfully sensitive experiments at Brookhaven, CERN, Fermilab, and Frascati on CP violation and rare decays of kaons; the prospect of definitive accelerator experiments on neutrino oscillations and the nature of the neutrinos; and a host of new experiments on the sensitivity frontier. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this ...

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The availability of new, high-intensity, cold and thermal neutron sources has opened the possibility of performing high-precision fundamental neutron physics experiments, including measurements that study the hadronic weak interaction and standard model test measurements, using neutron decay. The observables in these experiments are usually correlated with the direction of neutron polarization and are often very small (10 8 10 6). Mott-Schwinger scattering of polarized neutrons can produce spin-dependent shifts in beam centroids, which has the potential to produce significant systematic effects for these types of experiments. An accurate calculation of this process for neutral atoms and basic molecules has not been carried out for low neutron energies. In this work, we derive a general expression for the electromagnetic (Mott-Schwinger) contributions to the analyzing power for low-energy neutron scattering. We obtain numerical results for 11 ...

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Diffuse {gamma}-ray emission produced by the interaction of cosmic-ray particles with matter and radiation in the Galaxy can be used to probe the distribution of cosmic rays and their sources in different regions of the Galaxy. With its large field of view and long observation time, the Milagro Gamma Ray Observatory is an ideal instrument for surveying large regions of the Northern Hemisphere sky and for detecting diffuse {gamma}-ray emission at very high energies. Here, the spatial distribution and the flux of the diffuse {gamma}-ray emission in the TeV energy range with a median energy of 15 TeV for Galactic longitudes between 30{sup o} and 110{sup o} and between 136{sup o} and 216{sup o} and for Galactic latitudes between -10{sup o} and 10{sup o} are determined. The measured fluxes are consistent with predictions of the GALPROP model everywhere except for the Cygnus region (l {element_of} [65{sup o}, 85{sup o}]). For the Cygnus region, the flux is twice the predicted value. This ...

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Although the standard model of particle physics agrees perfectly with experimental data, it is unlikely the final theory describing particles and their interactions. New phenomena has been searched in the jets and missing transverse energy topology. Such phenomena may be due to the pair production of leptoquarks decaying into a quark and a neutrino or the pair production of stops decaying into a charm and a neutralino which is assumed to be the lightest supersymmetric particle. These searches have been performed with the Ddiamter detector at hadronic collider TeVatron with a center of mass energy of 1.96 TeV. This kind of searches needs a good understanding of the jet energy calibration. The determination of the relative jet energy scale has allowed us to reduce the systematic uncertainties on the jet energy measurement when comparing the data and the simulation. Moreover a new method has been developed in order to correct ...

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We discuss various reactions at future e"+e"- and #gamma##gamma# colliders involving real (beamstrahlung or backscattered laser) or quasi-real (bremsstrahlung) photons in the initial state and hadrons in the final state. The production of two central jets with large transverse momentum p_T is described in some detail; we give distributions for the rapidity and p_T of the jets as well as the di-jet invariant mass, and discuss the relative importance of various initial state configurations and the uncertainties that arise from the at present rather poor knowledge of the parton content of the photon. We also present results for 'mono-jet' production where one jet goes down a beam pipe, for the production of charm, bottom and top quarks, and for single production of W and Z bosons. Where appropriate, the two-photon processes are compared with annihilation reactions leading to similar final states. We also argue that the behaviour of the total ...

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I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.

CERN Document Server

ALICE (A Large Ion Collider Experiment) is the heavy-ion detector designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). Some specific calibration tasks are performed regularly for each of the 18 ALICE sub-detectors in order to achieve most accurate physics measurements. These procedures involve events analysis in a wide range of experimental conditions, implicating various trigger types, data throughputs, electronics settings, and algorithms, both during short sub-detector standalone runs and long global physics runs. A framework was designed to collect statistics and compute some of the calibration parameters directly online, using resources of the Data Acquisition System (DAQ), and benefiting from its inherent parallel architecture to process events. This system has been used at the experimental area for one year, and includes more than 30 calibration routines in ...

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Neutrinoless Double Beta Decay ($0\

CERN Document Server

This thesis describes hadron reconstruction at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) at CERN, Geneva. The focus is on the particle flow reconstruction of these objects. This thesis revisits the subject of the CMS calorimeters' non-linear response to hadrons. Data from testbeam experiments conducted in 2006 & 2007 is compared with simulations and substantial differences are found. A particle flow calibration to correct the energy response of the testbeam data is evaluated. The reconstructed jet response is found to change by ~ 5% when a data-driven calibration is used in place of the calibration derived from simulation. Collision data taken at the early stage of CMS' commissioning is also presented. The hadron response in data is determined to be compatible with testbeam results presented in this thesis. This thesis also details the use of neural networks to ...

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(I)Results are given for photoproduction of the D{sup *} at 103 GeV. Clean signals are seen for the decay D{sup *{+-}} {yields} {pi}{sup {+-}}D{sup 0} with the D{sup 0} decaying into both K{sup {-+}}{pi}{sup {+-}} and K{sup {-+}}{pi}{sup {+-}}{pi}{sup 0}. Analysis of the Dalitz plot for the K{pi}{pi} mode gives branching fractions (BFs) for K{sup {minus}}{rho}{sup +}, K{sup *{minus}}{pi}{sup +}, and {anti K}{sup *0}{pi}{sup 0} final states. The BF for D{sup 0} {yields} K{sup {minus}}{rho}{sup +}, much lower than a previous result, is in approximate agreement with the value expected for an l=1/2 final state. (II)Inelastic and elastic J/{psi} photoproduction on H is investigated at 103 GeV. The inelastic cross section with E{sub {psi}}/E{sub {gamma}} {lt} 0.9 is significantly lower than the corresponding result for muoproduction on Fe targets, but consistent with second-order perturbative QCD calculation. The mean p{sub +} of inelastic events is ...

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The central topic of this work is the study of the properties and the implementation of a Paul trap used for the measurement of the beta-neutrino angular correlation parameter in the decay of {sup 6}He. This coefficient provides a signature of the nature of the interactions involved in the weak interaction. The value of this coefficient can be deduced from the kinematical distribution of the decay events. An electromagnetic trap is used for the trapping of {sup 6}He{sup +} ions in a small volume. This trap has an open geometry that enables the detection in coincidence of the electron and the recoil ion emitted in the beta decay. A dedicated detection set up is used for the measurement of the electron energy, the ion time of flight and the position of the two particles for each event. A general description of the LPCTrap facility and of its performances is presented and shows that this set up is able to ...

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We find that tachyonic orbifold examples of AdS/CFT have corresponding instabilities at small radius, and can decay to more generic gauge theories. We do this by computing a destabilizing Coleman-Weinberg effective potential for twisted operators of the corresponding quiver gauge theories, generalizing calculations of Tseytlin and Zarembo and interpreting them in terms of the large-N behavior of twisted-sector modes. The dynamically generated potential involves double-trace operators, which affect large-N correlators involving twisted fields but not those involving only untwisted fields, in line with large-N inheritance arguments. We point out a simple reason that no such small radius instability exists in gauge theories arising from freely acting orbifolds, which are tachyon-free at large radius. When an instability is present, twisted gauge theory operators with the quantum numbers of the large-radius ...

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This study is one element of a larger engineering study effort by WHC to examine the feasibility of irradiated fuel and sludge consolidation in the KW Basin in response to TPA Milestone (target date) M-34-00-T03. The study concludes that up to 11,500 fuel storage canisters could be accommodated in the KW Basin with modifications. These modifications would include provisions for multi-tiered canister storage involving the fabrication and installation of new storage racks and installation of additional decay heat removal systems for control of basin water temperature. The ability of existing systems to control radionuclide concentrations in the basin water is examined. The study discusses requirements for spent nuclear fuel inventory given the proposed multi-tiered storage arrangement, the impact of the consolidated mass on the KW Basin structure, and criticality issues associated with multi-tiered storage.

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... coincidence spectrometry decay excited states gamma spectra half-life

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... beta decay coincidence spectrometry energy levels energy-level transitions

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Biofumigation with Muscodor albus was investigated to control four fungal decay pathogens (Phytophthora erythroseptica, Sclerotinia sclerotiorum, Botrytis cinerea and Penicillium expansum) and four bacterial pathogens (Erwinia carotovora pv. carotovora, Pseudomonas fluorescens, Escherichia coli, Listeria innocua) in controlled atmosphere conditions (regular air (20.8% O2+0.03% CO2), high CO2 (20.8% O2+15% CO2) or low O2 (1% O2+0.03% CO2)). In vitro experiments involved 48h exposure to M. albus at 3degreeC or 20degreeC, in vivo experiments involved 72h exposure to M. albus at 3degreeC. In vitro biofumigation with M. albus in regular air at 20degreeC killed all the pathogens. Bacterial growth was best controlled by M. albus at 20degreeC regardless of atmospheric conditions whereas fungal gro...

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Measurements of the relaxation of the D{sub 2}O stretch mode in vitreous As{sub 2}S{sub 3} are presented. Because the bending mode of the molecule offers an intra-molecular decay channel for the stretch mode, the decay scheme of the D{sub 2}O molecule is more complex than that of diatomic molecules. The asymmetric stretch mode of D{sub 2}O has a frequency of 2680 cm{sup -1}. To study the relaxation of this mode we applied a pump-probe technique, using intense psec; pulses of the Stanford Free Electron Laser. Due to the small cross-section of the vibrational mode, successful efforts were made to improve the signal to noise ratio by using a laser stabilization system and a tightly focused beam to increase the intensity, by averaging the signal with a kHz repetition rate and by using samples with an optimized D{sub 2}O concentration. A rapid relaxation rate on the order of 5 x 10{sup 9} sec{sup -1} at low temperature is found that increases with ...

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We discuss the consequence of local duality for elastic scattering, and derive a model-independent equation between structure functions at x ? 1 and elastic electromagnetic form factors. Then the electromagnetic form factors of proton are discussed using the quark-hadron duality theory. We also debate the form factor of proton in a bound state. It may be an effective approach to study the form factor of proton in media.

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We present a phenomenological model of the quark-hadron transition in neutrino-nucleon scattering. Using recently extracted weak nucleon transition form factors, we investigate the extent to which local and global quark-hadron duality is applicable in the neutrino F{sub 1}, F{sub 2} and F{sub 3} structure functions, and contrast this with duality in electron scattering. Our findings suggest that duality works relatively well for neutrino-nucleon scattering for the F{sub 2} and F{sub 3} structure functions, but not as well for F{sub 1}. We also calculate the quasi-elastic, resonance and deep inelastic contributions to the Adler sum rule, and find it to be satisfied to within 10% for 0.5 < Q{sup 2} < 2 GeV{sup 2}.

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Detailed level and decay schemes are presented for the nuclei of the A = 101 mass chain. The level properties obtained from decay and reaction experiments are shown in the drawings. Experimental methods, references, and comments are given in the text.

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... v. 33(4). beta-minus decay de-excitation delayed gamma radiation iron 64

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... Inst. of Modern Physics 7-5022-0983-2 180 p. beta decay ft value ground states

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A survey is given on the present status of the nucleon parton distributions and related precision calculations and precision measurements of the strong coupling constant {alpha}{sub s}(M{sup 2}{sub Z}). We also discuss the impact of these quantities on precision observables at hadron colliders. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The main subject of this thesis is the study of the hardronic final state in deep-inelastic electron-proton scattering. Theexperiment described in this thesis is performed with such a high resolution that the substructure of the proton is probed by the electron beam with a resolution of less than 10{sup -15} cm. (orig./HSI).

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On the basis of the phenomenological model for baryon resonance production in lepton nucleon and lepton nucleus scattering we investigate to what extent quark hadron duality is applicable to the neutrino structure functions and how it compares with duality in electron scattering.

International Nuclear Information System (INIS)

The main problems arising in decommissioning nuclear-powered submarines (NPS) relate to choosing a concept of handling reactor compartments followed by handling technology development. Reactor compartments (RC) are characterized with extremely space-saving or integral layout of large-size power equipment and systems, restricted access for dismantling, high radiation dose rates in a number of bays of RC. The above RC features pose a problem to find optimum option of RC utilization which on the one hand would be the most cost efficient, and the safest as possible on the other, i.e. dose commitments of personnel involved should be minimum, and effect on population and environment should be negligible. The main radiation factors specifying safety in RC handling at any decommissioning stage are as follows: (1) total radioactivity integrated in reactor facility (RF); (2) distribution of this radioactivity through RF equipment and structures; (3) forms the radioactivity ...

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This guide describes the simulator`s governing equations, constitutive functions and numerical solution algorithms of the STOMP (Subsurface Transport Over Multiple Phases) simulator, a scientific tool for analyzing multiple phase subsurface flow and transport. The STOMP simulator`s fundamental purpose is to produce numerical predictions of thermal and hydrologic flow and transport phenomena in variably saturated subsurface environments, which are contaminated with volatile or nonvolatile organic compounds. Auxiliary applications include numerical predictions of solute transport processes including radioactive chain decay processes. In writing these guides for the STOMP simulator, the authors have assumed that the reader comprehends concepts and theories associated with multiple-phase hydrology, heat transfer, thermodynamics, radioactive chain decay, and nonhysteretic relative permeability, saturation-capillary pressure constitutive functions. ...

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I review recent developments in quark-hadron duality in inclusive electron-nucleon scattering. Matrix elements of twist-4 operators extracted from moments of the spin-dependent g1 structure function suggest that duality violating higher twists are small above Q2 {approx} 1 GeV2. The x dependence of local duality is analyzed within a quark model framework, and mechanisms are identified for spin-flavor symmetry breaking which underpin the behavior of structure functions at large x.

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Recent developments in the physical model of 1 MeV to 100 TeV hadron and lepton interactions with nuclei and atoms are described. These include a new nuclear cross section library, a model for soft pion production, the cascade-exciton model, the dual parton model, deuteron-nucleus and neutrino-nucleus interaction models, detailed description of mu, pi and anti p absorption and a unified treatment of muon and charged hadron electromagnetic interactions with matter. New algorithms are implemented into the MARS13(98) Monte Carlo code and benchmarked against experimental data. The code capabilities to simulate cascades and generate a variety of results in complex media have been also enhanced.

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The paper describes an application of the tree classification method Random Forest (RF), as used in the analysis of data from the ground-based gamma telescope MAGIC. In such telescopes, cosmic gamma-rays are observed and have to be discriminated against a dominating background of hadronic cosmic-ray particles. We describe the application of RF for this gamma/hadron separation. The RF method often shows superior performance in comparison with traditional semi-empirical techniques. Critical issues of the method and its implementation are discussed. An application of the RF method for estimation of a continuous parameter from related variables, rather than discrete classes, is also discussed.

International Nuclear Information System (INIS)

... beta spectrometers decay energy-level transitions k conversion l conversion

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Short communication

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This two-volume reference uses many equations to provide detailed information on atomic and nuclear decay phenomena.

CERN Document Server

It has by now been established that standard QCD factorization using transverse momentum dependent parton distribution functions fails in hadro-production of nearly back-to-back hadrons with high transverse momentum. The essential problem is that gauge invariant transverse momentum dependent parton distribution functions cannot be defined with process-independent Wilson line operators, thus implying a breakdown of universality. This has led naturally to proposals that a correct approach is to instead use a type of "generalized" transverse momentum dependent factorization in which the basic factorized structure is assumed to remain valid, but with transverse momentum dependent parton distribution functions that contain non-standard, process dependent Wilson line structures. In other words, to recover a factorization formula, it has become common to assume that it is sufficient to simply modify the Wilson lines in the parton correlation functions for each separate ...

CERN Document Server

Complete factorization scheme analysis of $F_2^{\\gamma}(x,Q^2)$ in the next--to--leading order QCD is performed. It is shown that the presence of the inhomogenous term in the evolution equations for parton distribution functions of the photon implies qualitative change in the way factorization mechanism works in photon--hadron and photon--photon collisions as compared to hadron--hadron ones. The incompletness of the existing NLO analyses of $F_2^{\\gamma}(x,Q^2)$ is pointed out and its origins traced back to the misinterpretation of the behaviour of $q^{\\gamma}(x,M)$ as a function of in the LO photonic coefficient function $C_{\\gamma}^{(0)}(x)$ is given and smooth transition between the properties of virtual and real photon discussed. A simple way of avoiding the problems with the term $\\ln(1-x)$ appearing in the standard expression for $C_{\\gamma}^{(0)}(x)$ in the case of the reaal photon is proposed.

CERN Document Server

The Large Hadron Collider (LHC) will be equipped with several thousands of superconducting corrector magnets. Among the largest ones are the superconducting trim quadrupoles (MQTL). These twin-aperture magnets with a total mass of up to 1700 kg have a nominal gradient of 129 T/m at 1.9 K and a magnetic length of 1.3 m. Sixty MQTL are required for the LHC, 36 operating at 1.9 K in and 24 operating at 4.5 K. The paper describes the design features, and reports the measured quench performance and magnetic field quality of the production magnets. The MQTL magnet production is shared between CERN and industry. This sharing is simplified due to the modular construction, common to all twin-aperture correctors.

CERN Document Server

Experimental studies of charmless semileptonic B decays can be broadly categorized into inclusive and exclusive measurements depending on how the final states are treated. The inclusive method measures the decay rate $\\Gamma(B \\to X_u \\ell \

Energy Technology Data Exchange (ETDEWEB)

Detailed level and decay schemes and the experimental reaction and decay data on which they are based are presented for nuclei with mass number A = 242; the experimental data are evaluated. Adopted values for level and ..gamma..-ray energies, ..gamma..-intensities, as well as other nuclear properties are given.

CERN Document Server

We give a summary of the discussions in Working Group V of the CKM2010 workshop dealing with determinations of the angle gamma of the unitarity triangle of the Cabibbo-Kobayashi-Maskawa matrix from B-meson decays into charmed final states.

British Library Electronic Table of Contents (United Kingdom)

This paper introduces briefly neutrinoless Double Beta Decay and discusses its implications for neutrino physics. After a presentation of general experimental concepts, such as the various proposed methodological approaches and the sensitivity, the current experimental situation is concisely reviewed.

International Nuclear Information System (INIS)

... bismuth 203 chemical reactions cyclotrons decay helium 3 beams impurities

Science.gov (United States)

It is shown that there may be a correlation between the galactic cosmic rays and the solar neutrino

International Nuclear Information System (INIS)

The measurements of the nuclear decay of actinide isotopes and the evaluation of the radioactive properties of nuclide with the mass 242 is discussed in this paper.

International Nuclear Information System (INIS)

... comparative evaluations energy-level transitions half-life internal conversion

CERN Document Server

The absolute branching fractions for the decays $D^0 \\to K^-e ^+\

International Nuclear Information System (INIS)

Gamma-rays and conversion electrons emitted in the "1"1"7Cs and "1"1"7Xe decays have been studied from on-line mass-separated "1"1"7Cs sources at the ISOLDE facility. A new "1"1"7Xe decay scheme has been constructed and a level scheme has been established for the "1"1"7Cs decay. The results are discussed in the frame of our recent knowledge about odd-mass neutron-deficient I and Xe systematics.

International Nuclear Information System (INIS)

... angiotensin gallium 67 lungs lysozyme patients sarcomas beta decay

International Nuclear Information System (INIS)

The nucleon decay of subbarrier single-particle states with large angular momentum and parity opposite to that of the shell in soft spherical nuclei is considered. It is shown that the reduced probabilities of the nucleon decay into the ground state (0"+) and into the first excited (2"+) state of the daughter nucleus have qualitatively different energy dependences. (orig.).

Energy Technology Data Exchange (ETDEWEB)

New measurements of relative gamma-ray emission probabilities in the decay of [sup 101]Mo and [sup 101]Tc are reported. Previously published conversion-electron data have been used along with the gamma-ray data to formulate self-consistent decay schemes. (orig.)

International Nuclear Information System (INIS)

The #gamma# rays following the #beta# decays of "8"8Kr and "8"8Rb have been studied, using both large volume Ge(Li) detectors for singles and coincidence measurements and anti-Compton spectrometry for singles measurements. Level schemes for "8"8Rb and "8"8Sr were constructed from the data and 74 of 81 #gamma# rays observed in the decay of "8"8Kr were placed in the "8"8Rb level scheme with 23 excited states. For the decay of "8"8Rb, all of the observed 27 #gamma# rays have been placed in the (well known) level structure of "8"8Sr. Spin and parity assignments have been deduced from #beta#-decay logft values and #gamma#-ray transition patterns. Possible shell model interpretations are presented for the level schemes.

Energy Technology Data Exchange (ETDEWEB)

We review the physics of structure functions at low Q{sup 2}, focusing on the phenomenon of quark-hadron duality and the resonance-scaling transition, both phenomenologically and in the context of quark models. We also present a new implementation of target mass corrections to nucleon structure functions which, unlike existing treatments, has the correct kinematic threshold behavior at finite Q{sup 2} in the x -> 1 limit.

International Nuclear Information System (INIS)

Quark models of production of cumulative particles and the EMC effect are analyzed. It is shown that all these models are characterized by a universal relation between the spectrum of cumulative nucleons and the cross section for cumulative particles containing valence quarks of the nucleus. This relation is tested for the deuteron, and the role of secondary nuclear processes for heavy nuclei is discussed. It is noted that the ''sea'' cumulative particles (K"-, p-bar) are particularly important for understanding the nature of the difference between the structure functions of a nucleus and of a free nucleon.

Energy Technology Data Exchange (ETDEWEB)

The upgraded CDF II detector has collected first data during the initial operation of the Tevatron accelerator in Run II. The simulation of the CDF electromagnetic and hadronic central and upgraded plug (forward) calorimeter is based on the Gflash calorimeter parameterization package used within the GEANT based detector simulation of the Run II CDF detector. We present the results of tuning the central and plug calorimeter response to test beam data.

CERN Multimedia

The Large Hadron Collider is at the top of world-wide science for particle physics. It promises to open the road to a new knowledge of the universe and its nature. Luciano Maiani and Robert Aymar, actual and future Director Generals of CERN, explain the aims of this most powerful instrument, the difficulties and the industrial repercussions, among which will be the "Grid", that will change the telecommunications (4 pages)

CERN Document Server

The status of the IEEE 802.3 standard is reviewed and prospects for the future, including the new 10 Gigabit version of Ethernet, are discussed. The relevance of Ethernet for experiments at the CERN Large Hadron Collider is considered, with emphasis on on-line applications and areas which are technically challenging. 8 Refs.

International Nuclear Information System (INIS)

Quark models of cumulative particle production and EMS effect are analyzed. All the models are characterized by a universal relationship between the spectrum of cumulative nucleons and the cross section of cumulative particles containing valence nuclear quarks. This relationship is tested for a deuteron. The role is discussed played by secondary nuclear processes for heavy nuclei. A special role of ''sea'' cumulative particles (K"-, p-bar) is pointed out in understanding the nature of the difference between the structure functions of a nucleus and of free nucleon.

Energy Technology Data Exchange (ETDEWEB)

The author notes that if hadrons are gravitationally stabilized ``black holes``, as discrete physics suggests, it is possible that partons, and in particular quarks, could be modeled as tachyons, i.e. particles having v{sup 2} > c{sup 2}, without conflict with the observational fact that neither quarks nor tachyons have appeared as ``free particles``. Some consequences of this model are explored.

International Nuclear Information System (INIS)

A theoretical model was developed to simulate this phenomenon, under some specific assumptions. The model simulates: the generation and decay of radon within the soil; its transport throughout the soil due to diffusion and convection induced by the pressure disturbance applied at a crack in the basement; its entrance into the house through the crack; and the resultant indoor radon concentration. The most important assumptions adopted in the model were: a steady-state condition; a house with a basement; a geometrically well-defined crack at the wall-floor joint in the basement; and a constant negative pressure applied at the crack in relation to the outside atmospheric pressure. Two three-dimensional finite-difference computer programs were written to solve the mathematical equations of the model. The first program, called PRESSU, was used to calculate: the pressure distribution within the soil as a result of the applied disturbance pressure at the crack; and the ...

International Nuclear Information System (INIS)

Plasma-deposited thin films prepared at room temperature, ranging from 46 to 250 A of PdAu on #approx#45-50 A Si-oxide and Si-oxynitride films grown on Si wafers were studied. Grazing incidence X-ray diffraction, X-ray reflectivity, and XPS depth profile techniques were used to characterize the thin films. A reactive interface involving Pd- and Au-silicides is formed, linking the thin film to the Si-oxide and Si-oxynitride films: a small fraction of Pd and Au atoms from PdAu migrate into the Si substrate, first penetrating the oxide layer, and the small fraction of Si atoms from the oxide layer migrate into the PdAu film and form a silicide interlayer consisting of a reactive interface made up of mixtures of Au- and Pd-silicides interspersed within the matrix of PdAu and substrate. The concentration profiles of these silicides have a maximum at the interface with decay on both sides. The density and the face-centered cubic (fcc) lattice ...

Energy Technology Data Exchange (ETDEWEB)

The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects are calculated, with reference to ITER/NET (International Thermonuclear Experiment Reactor/Next European Torus), STARFIRE (a ...

Indian Academy of Sciences (India)

central server with search facility involving all partner journals ...

International Nuclear Information System (INIS)

The study of B#->##tau#"+#tau#"-(X) decays can provide us with a better understanding of the third generation, and can be a useful probe of physics beyond the standard model. We present a model-independent analysis of these decays. We classify new physics that can largely enhance the decay rates and we discuss the constraints implied by other processes. Experimentally, flavor-changing neutral current B decays into final state #tau# close-quote s are still unconstrained. Searches for B decays with large missing energy at CERN LEP provide the first limits. We estimate that existing data already imply bounds on the B_d#->##tau#"+#tau#"-, B_s#->##tau#"+#tau#"-, and B#->#X#tau#"+#tau#"- decay rates at the few percent level. Although these bounds are over four orders of magnitude above the standard model predictions, they provide the first constraints on ...

International Nuclear Information System (INIS)

Decay sequences based on the 1/2"+[660] proton orbital have been identified in "1"7"1Ta and "1"7"7Re based on spin, parity, and large alignment. This decay sequence is observed higher in energy than predicted in cranking calculations based on modified oscillator potentials. Similarly known 1/2"-[541] decay sequences in these and other neighbouring isotopes are observed lower in energy than predicted. A reduction in the strength of the spin-orbit potential for protons is suggested as a solution to these problem. (orig.).

CERN Document Server

The Dalitz plot of $\\eta^{\\prime} \\to \\eta \\pi^+ \\pi^-$ decay is studied using $(225.2\\pm2.8)\\times 10^6$ $\\jpsi$ events collected with the BESIII detector at the BEPCII $e^+e^-$ collider. With the largest sample of $\\eta^{\\prime}$ decays to date, the parameters of the Dalitz plot are determined in a generalized and a linear representation. Also the branching fraction of $\\jpsi \\to \\gamma \\eta^{\\prime}$ is determined to be $(4.84\\pm0.03\\pm0.24)\\times 10^{-3}$, where the first error is statistical and the second systematic.

CERN Document Server

The recent measurements by the BES Collaboration of J/psi decays into a photon and a proton-antiproton pair indicate a strong enhancement at the proton-antiproton threshold not observed in the decays into a neutral pion and a proton-antiproton pair. Is this enhancement due to a proton-antiproton quasi-bound state or a baryonium? A natural explanation follows from a traditional model of proton-antiproton interactions based on G-parity transformation. The observed proton-antiproton structure is due to a strong attraction in the 1S0 state, and possibly to a near-threshold quasi-bound state in the 11S0 wave.

Energy Technology Data Exchange (ETDEWEB)

The theory of ..cap alpha.. decay in first-order perturbation theory is presented. The theory is designed for a strongly deformed nucleus in an isomeric state which changes its deformation dynamically through decay from a very deformed to an almost spherical shape. It is shown that other channels are not coupled to the ..cap alpha.. channel in first-order perturbation theory. The collective degrees of freedom of the daughter nucleus are described by shape vibrational states, eigenstates of a Hamiltonian whose potential has two minima. The parent nucleus is described by dynamically coupling the vibrational degrees of freedom to the ..cap alpha..-particle motion and also taking rotations into account. The ..cap alpha.. particle is taken to be a point-like particle. The theory is applied to the ..cap alpha.. decay of the isomeric state of /sub 95//sup 242/Am.

International Nuclear Information System (INIS)

German 2001 p. 253-258 Germany Hages, P. Stratmann, W. STEAG encotec

International Nuclear Information System (INIS)

The decay of mass-separated samples of the previously unknown nuclide "7"1Br have been investigated by means of the Chalk River on-line isotope separator. Eleven #gamma#-transitions were assigned to the decay of this nuclide and its half-life was measured to be 21.4 +- 0.6 s. A simple decay scheme for "7"1Br has been constructed incorporating six levels in its daughter, "7"1Se. The half-life of the first excited state in "7"1Se was measured to be 5.5 +- 1.0 #mu#s and the transition from this state to the ground state was found to be highly converted. Systematic trends in the level schemes of "6"7Zn, "6"9Ge and "7"1Se are investigated. (orig.).

Energy Technology Data Exchange (ETDEWEB)

In April and May of 1999 the Berkeley Gas-filled Separator was used to search for the production and decay of element 118 from the {sup 86}Kr + {sup 208}Pb reaction, according to Smolanczuk's predictions of relatively large production rates. Three decay chains, each consisting of an implanted heavy ion, followed by a rapid (ms) succession of high-energy (>10 MeV) alpha-particle decays were detected. These chains are consistent with the production and decay of element 118 with mass number 293. These results a) show experimental evidence for the existence of shell-stabilized superheavy elements, b) provide experimental values for refinement of nuclear mass models in the superheavy element region, and, most importantly, c) present a new' reaction pathway for the production of superheavy elements. (author)

CERN Document Server

We report a measurement of the branching fractions for $B^{0} \\rightarrow \\pi^- \\ell^+\

Energy Technology Data Exchange (ETDEWEB)

The authors present the results of a search for W{prime} boson decaying to electron-neutrino pairs in p{bar p} collisions at a center-of-mass energy of 1.96 TeV, using a data sample corresponding to 205 pb{sup -1} of integrated luminosity collected by the CDF II detector at Fermilab. They observe no evidence for this decay mode and set limits on the production cross section times branching fraction, assuming the neutrinos from W{prime} boson decays to be light. If they assume the manifest left-right symmetric model, they exclude a W{prime} boson with mass less than 788 GeV/c{sup 2} at the 95% confidence level.

Energy Technology Data Exchange (ETDEWEB)

We study CP-violating phenomena in the production, mixing and decay of a coupled system of CP-violating neutral Higgs bosons at {gamma}{gamma} colliders, assuming a Minimal Supersymmetric Standard Model (MSSM) Higgs sector in which CP violation is radiatively induced by phases in the soft supersymmetry-breaking gaugino masses and third-generation trilinear squark couplings. We discuss CP asymmetries in the production and decays of {mu}{sup +}{mu}{sup -}, {tau}{sup +}{tau}{sup -}, b-bar b and t-bar t pairs. We find large asymmetries when two (or all three) neutral Higgs bosons are nearly degenerate with mass differences comparable to their decay widths, as happens naturally in the CP-violating MSSM for values of tan{beta}-bar 5 (30) and large (small) charged Higgs-boson masses.

Energy Technology Data Exchange (ETDEWEB)

The estimation of radiation dose to man from either external or internal exposure to radionuclides requires a knowledge of the energies and intensities of the atomic and nuclear radiations emitted during the radioactive decay process. The availability of evaluated decay data for the large number of radionuclides of interest is thus of fundamental importance for radiation dosimetry. This handbook contains a compilation of decay data for approximately 500 radionuclides. These data constitute an evaluated data file constructed for use in the radiological assessment activities of the Technology Assessments Section of the Health and Safety Research Division at Oak Ridge National Laboratory. The radionuclides selected for this handbook include those occurring naturally in the environment, those of potential importance in routine or accidental releases from the nuclear fuel cycle, those of current interest in nuclear medicine and ...

CERN Document Server

We discuss an experimental technique aimed at tagging electron neutrinos in multi-GeV artificial sources on an event-by-event basis. It exploits in a novel manner calorimetric and tracking technologies developed in the framework of the LHC experiments and of rare kaon decay searches. The setup is based on an instrumented decay tunnel equipped with tagging units that intercept secondary and tertiary leptons from the bulk of undecayed pi+ and protons. We show that the taggers are able to reduce the nue contamination originating from K_e3 decays by about one order of magnitude. Only a limited suppression (~60%) is achieved for nue produced by the decay-in-flight of muons; for moderate beam powers, similar performance as for K_e3 can be reached supplementing the tagging system with an instrumented beam dump.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

... 45 p. absorption spectroscopy errors lead lead 203 beta decay radioisotopes

CERN Document Server

CERN, the European Laboratory for Particle Physics, is working towards the construction of the Large Hadron Collider (LHC), a high-energy, high-luminosity particle accelerator and collider [1] of 26.7 km circumference, due to start producing frontier physics, by bringing into collision intense proton and ion beams with centre-of-mass energies in the TeV-per-constituent range, at the beginning of the next century. The key technology for achieving this ambitious scientific goal at economically acceptable cost is the use of high-field superconducting magnets using Nb-Ti conductor operating in superfluid helium [2]. To maintain the some 25 km of bending and focusing magnets at their operating temperature of 1.9 K, the LHC cryogenic system will have to produce an unprecedented total refrigeration capacity of about 20 kW at 1.8 K, in eight cryogenic plants distributed around the machine circumference [3]. This has requested the undertaking of an industrial development ...

International Nuclear Information System (INIS)

Complete calculations of the accelerator related background in the muon spectrometer of the CMS detector at the Large Hadron Collider are presented. The simulations have been performed with the STRUCT multi-turn tracking code and the MARS and FLUKA cascade codes taking into account latest information of the LHC lattice, vacuum conditions, beam cleaning system and the shielding and layout of the CMS experiment. Beam loss distributions in the interaction regions and their vicinities and their contribution to the background levels in the muon spectrometer of CMS are analyzed. The studies show that hadronic and electromagnetic components of machine background are efficiently suppressed by the proposed CMS shielding. High energy muons penetrate through the shielding, but in positions of significance they do not contribute more than a few percent compared to the background generated by the pp-collisions. It is anticipated that the relative ...

Energy Technology Data Exchange (ETDEWEB)

Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting the joint project integrating both the Neutron Science Project (NSP) of JAERI and the Japan Hadron Facility Project (JHF) of KEK for comprehensive studies on basic science and technology using high-intensity proton accelerator. This document describes the joint project prepared by the Joint Project Team of JAERI and KEK to construct accelerators and research facilities necessary both for the NSP and the JHF at the site of JAERI Tokai Establishment. It was originally written in English and translated into Japanese with some corrections. (author)

CERN Document Server

Supersymmetry, a new symmetry that relates bosons and fermions in particle physics, still escapes observation. Search for SUSY is one of the main aims of the recently launched Large Hadron Collider. The other possible manifestation of SUSY is the Dark Matter in the Universe. The present lectures contain a brief introduction to supersymmetry in particle physics. The main notions of supersymmetry are introduced. The supersymmetric extension of the Standard Model - the Minimal Supersymmetric Standard Model - is considered in more detail. Phenomenological features of the MSSM as well as possible experimental signatures of SUSY at the LHC are described. The DM problem and its possible SUSY solution is presented.

CERN Document Server

We consider the impact of a 4th generation on Higgs to $\\gamma\\gamma$ and $WW,ZZ$ signals and demonstrate that the Tevatron and LHC have essentially eliminated the possibility of a 4th generation if the Higgs is SM-like and has mass below 200 GeV. We also show that the absence of enhanced Higgs signals in current data sets in the $\\gamma\\gamma$ and $WW,ZZ$ final states can strongly constrain (almost eliminate) the possibility of a 4th generation in two-Higgs-doublet models of type II (in the MSSM).

International Nuclear Information System (INIS)

#pi#"#+-# and K"#+-# cumulative production in pA #-># #pi#"#+-#+x and pA #-># K"#+-#+x reactions at 10.14 GeV proton beam energy on nuclei (Be-Ta) was invesigated. Measurements were conducted using FAS-1 focusing hadron spectrometer. Invariant cross sections of #pi#"#+-# and K"#+-# cumulative production, values of ratio of this cross sections, dependences of production cross sections for pions and kaons on cumulative number and mass number of nucleus target, as well as on transverse momentum are measured. Difference of cumulative meson spectra occurring in different nuclei fragmentation is discussed in terms of flucton model. 17 refs.; 14 figs.

Energy Technology Data Exchange (ETDEWEB)

We consider propagation of relativistic heavy nuclei injected by a young pulsar into the radiation field of a massive companion. If the binary system (BS) is compact enough, then the nuclei suffer multiple photodisintegrations in collisions with thermal photons coming from the massive star (MS). Due to the propagation effects of charged particles in the magnetic field of the MS some hadrons can impinge onto the MS surface at large angles. We calculate the fluxes of produced neutrinos as a function of the viewing angle measured from the plane of the BS. It is found that significant fluxes of neutrinos should be also expected in the case of non-eclipsing BSs.

CERN Document Server

multi-parton interactions and underlying event structure, $\\gamma$-mediated processes and luminosity determination, Monte Carlo tuning and even MSSM Higgs discovery in central exclusive production. In this article, the forward detector instrumentation around the CMS interaction point is described and the prospects for diffractive and forward physics using the CMS forward detectors are summarized. In addition, first observation of forward jets as well as early measurements of the forward energy flow in the pseudorapidity range $3.15

CERN Document Server

The homogeneity of the magnetic field in the LHC dipoles strongly depends on the correct position of the superconducting cables: this is related to the quality of the dipole components, such as the dimension of the coil spacers (copper wedges), of the cable and of the collars. The performance in operational conditions is also affected by the magnetization of the cables. In this work, we analyse the measurements of these quantities during the production of the 1276 LHC dipoles, their trends, and the relation to the measured magnetic field. A novel mtehod to locate electrical shorts based on the analysis of magnetic measurements is also presented, and applications to 15 dipoles reascued during the production is given.

CERN Document Server

We discuss the recent excess seen by the CDF Collaboration in the dijet invariant mass distribution produced in association with a $W$ boson. We analyze the possibility of such a signal within the context of a $U(1)_X$ Stueckelberg extension of the Standard Model where the new gauge boson couples only to quarks. In addition to the analysis of the $Wjj$ anomaly we also discuss the production of $Zjj$ and $\\gamma jj$ at the Tevatron. The analysis is then extended to the Large Hadron Collider with $\\sqrt{s}=7 {\\rm TeV}$ and predictions for the dijet signals are made.

Energy Technology Data Exchange (ETDEWEB)

Three phosphate based ceramics were studied for the immobilization of tri- and tetravalent actinides: britholites Ca{sub 9}Nd{sub 1-x}An{sub x} {sup IV}(PO{sub 4}){sub 5-x}(SiO{sub 4}){sub 1+x}F{sub 2}, monazites/brabantites Ln{sub 1-2x}{sup III}Ca{sub x}An{sub x}{sup IV}PO{sub 4} and Thorium Phosphate Diphosphate (TPD) Th{sub 4-x}An{sub x}{sup IV}(PO{sub 4}){sub 4}P{sub 2}O{sub 7}. For each material, the incorporation of Th, U(IV), or Ce(IV) in the structure was examined. This work was the early beginning of the incorporation of {sup 239}Pu and/or {sup 238}Pu in order to evaluate the effects of {alpha} -decay on these three crystallographic structures. The syntheses were carried out using dry chemistry methods, involving mechanical grinding then heating treatment (1100 deg C {<=} {theta} {<=} 1400 deg C). For britholites, we showed that the incorporation of thorium was complete for weight loading lower than 20 wt.% through the ...

Energy Technology Data Exchange (ETDEWEB)

A Bianchi type-IX cosmological model has been found as a solution of Einstien's vacuum field equations with a cosmological constant. The solution represents a rotating generalziation fo the de Sitter universe. This universe shows a transition to exponential expansion and the vorticity begins to decay exponentially at the grand-unified-theory time. The point of time for this transition is independent of the magnitude of the vorticity. During the Guth inflationary era the vorticity decays by a factor of the order 10 US.

International Nuclear Information System (INIS)

A new channel of nonlinear ionization of quantum system in a strong laser field is discussed. The probability of spontaneous radiation decay from the ground state in a short-range potential to the final Volkov wave function, is calculated by the first order of the perturbation theory. It is shown that this process at high intensities of the laser field will be comparable with the high harmonic generation. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The lowest excited level in Ni-like ions, 3d{sup 9}4s {sup 3}D{sub 3}, decays only via a magnetic octupole (M3) decay. They present calculated values of transition wavelengths and rates for ions with 30 {le} Z {le} 100. They have observed this line in Xe{sup 26+}, using the Livermore EBIT-I electron beam ion trap and a microcalorimeter, as well as a high-resolution flat-field grating spectrometer.

Energy Technology Data Exchange (ETDEWEB)

It is shown that observations of the lithium isotope ratio in high surface temperature Population II stars may be critical to cosmological nucleosynthesis models. In particular, decaying particle scenarios as derived in some supersymmetric models may stand or fall with such observations. 18 references.

International Nuclear Information System (INIS)

The European Research and Development Program on decay heat removal by natural convection for the European Fast Reactor (EFR) covers the calculational methods and the model experiments performed for code validation. The studies concentrate on important physical effects of the cooling modes within the primary system and the direct reactor cooling circuits and include fundamental tests as well as reactor experiments. (author)

CERN Document Server

The radiative decay K->mu nu gamma has been studied at ISTRA+ setup in a new kinematical region. About 46K events of K->mu nu gamma have been observed. The sign and value of Fv-Fa have been measured for the first time. The result is Fv-Fa=0.16(4)(5).

Science.gov (United States)

The Interim Decay Storage tank (IDS) will be located in a concrete cell in the FFTF reactor building. The tank will have capacity to store 112 driver fuel assemblies and 10 test assemblies in sodium. A criticality safety analysis for the design of the IDS tank was performed. From the analysis, it is concluded that under normal operating conditions and minor abnormal conditions that might shift the fuel, the IDS tank will remain adequately subcritical. (auth)

International Nuclear Information System (INIS)

The #beta# decay half-lives of neutron-rich isotopes with Z=24-28 are calculated in the QRPA with a Gamow-Teller residual interaction. For odd-mass and odd-odd systems QRPA phonon correlations are introduced to quasiparticle transitions in first-order perturbation. The calculated half-lives agree very well with the experimental values. For later application of this model to nuclei far from stability, we have examined the dependence of the calculated half-lives on the model parameters. (orig.).

Energy Technology Data Exchange (ETDEWEB)

The authors measure the dipion mass spectrum in X(3872) {yields} J/{psi}{pi}{sup +}{pi}{sup -} decays using 360 pb{sup -1} of {bar p}p collisions at {radical}s = 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity ({sup 3}S{sub 1}, {sup 1}P{sub 1}, and {sup 3}D{sub J}) charmonia decaying to J/{psi}{pi}{sup +}{pi}{sup -}, as well as event C-parity states in which the pions are from {rho}{sup 0} decay. The latter case also encompasses exotic interpretations, such as a D{sup 0}{bar D}*{sup 0} molecule. Only the {sup 3}S{sub 1} and J/{psi} {rho} hypotheses are compatible with the data. Since {sup 3}S{sub 1} is untenable on other grounds, decay via J/{psi} {rho} is favored, which implies C = +1 for the X(3872). Models for different J/{psi}-{rho} angular momenta L are considered. Flexibility in the models, especially the introduction of {rho}-{omega} ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Science.gov (United States)

Thesis. Five-particle shell-model calculations, using a spin-dependent potential, were performed for the nucleus /sup 101/Tc. The effects of varying the single-particle energy differences and the strengths of the spin-dependent and pairing terms are discussed. The isobars /sup 101/Mo and /sup 101/Tc were chemically separated to enable the detailed study of their decay schemes. As a result, 184 gamma rays were observed in the decay of /sup 101/Mo, and 169 of them were assigned to 45 levels in /sup 101/Tc. In the decay of /sup 101/Tc, 27 gamma rays were observed, and 26 of them were assigned to 11 levels in /sup 101/Ru. In a study of the decays of /sup 142/Xe and /sup 142/Cs the TRI STAN on-line isotope separator was used to separate the 142 mass chain produced in /sup 235/U fission with /sup 142/2Xe as the emanating and accelerated nuclide. Isobaric separation of /sup ...

Energy Technology Data Exchange (ETDEWEB)

An analysis is presented of the electron temperature in a linear device which includes the effect of thermal conduction, heat flux limit, radiation, and end plugs. It is found that the thermal conduction and the heat flux limit are dominant in the initial phase of cooling, while the later phase is almost completely controlled by radiation that spatially homogenizes the temperature distribution. In the case of bremsstrahlung, within the frame of the present model, the temperature decays to zero in a finite time. This process takes the form of a cooling wave that moves from the ends of the column to the center. Impurities cause a milder, exponential decay, which is still much faster than the algebraic conduction decay. The thermal effectiveness of the end plugs is described by a convective transfer coefficient h/sub p/. Its scaling law (in terms of the coupled plamsa-plug system) reveals that a very high plug-plasma density ...

CERN Document Server

We propose an X-ray mission called Xenia to search for decaying superweakly interacting Dark Matter particles (super-WIMP) with a mass in the keV range. The mission and its observation plan are capable of providing a major break through in our understanding of the nature of Dark Matter (DM). It will confirm, or reject, predictions of a number of particle physics models by increasing the sensitivity of the search for decaying DM by about two orders of magnitude through a wide-field imaging X-ray spectrometer in combination with a dedicated observation program. The proposed mission will provide unique limits on the mixing angle and mass of neutral leptons, right handed partners of neutrinos, which are important Dark Matter candidates. The existence of these particles is strongly motivated by observed neutrino flavor oscillations and the problem of baryon asymmetry of the Universe. In super-WIMP models, the details of the formation of the cosmic ...

Science.gov (United States)

In this work, the half-life of the {sup 155}Sm beta{sup -} decay was determined using enriched {sup 154}Sm samples submitted to irradiation in the IEA-R1 reactor of IPEN; the activity of the samples were followed for 4-5 consecutive half lives using a 198 cm{sup 3} HPGe detector. The data was corrected using a non paralizable dead time correction and fitted to an exponential decay function using a non linear fitting procedure developed on the MatLab platform. The resulting value--T{sub 1/2} = 22.180(26) min--was compatible to the one found in the literature, with a lower uncertainty.

CERN Document Server

The decay psi(2S)-->K_S K_L is observed for the first time using psi(2S) data collected with the Beijing Spectrometer (BESII) at the Beijing Electron Positron Collider (BEPC); the branching ratio is determined to be B(psi(2S)-->K_S K_L) = (5.24\\pm 0.47 \\pm 0.48)\\times 10^{-5}. Compared with J/psi-->K_S K_L, the psi(2S) branching ratio is enhanced relative to the prediction of the perturbative QCD ``12%'' rule. The result, together with the branching ratios of psi(2S) decays to other pseudoscalar meson pairs (\\pi^+\\pi^- and K^+K^-), is used to investigate the relative phase between the three-gluon and the one-photon annihilation amplitudes of psi(2S) decays.

International Nuclear Information System (INIS)

The activities "1"0"1Mo and "1"0"1Tc produced from neutron capture by natural Mo were chemically separated and studied using Ge(Li) #gamma#-ray detectors. Out of 185 transitions observed in the decay of "1"0"1Mo, 170 were assigned to 44 excited levels in "1"0"1Tc. For the decay of "1"0"1Tc, 26 of 27 transitions were placed among 10 excited levels in "1"0"1Ru. The interpretation of the "1"0"1Tc level scheme using the shell-model approach is not satisfactory even for a five-particle calculation. Systematics of odd-A level structures in the region of A=101 indicate that the level structure of "1"0"1Tc could be due partly to the onset of collective effects.

CERN Document Server

An effective computer program for three dimensional relativistic hydrodynamical model has been developed. It implements a new approach to the early hot phase of relativistic heavy-ion collisions. The computer program simulates time-space evolution of nuclear matter in terms of ideal-fluid dynamics. Equations of motions of hydrodynamics are solved making use of finite difference methods. Commonly-used algorithms of numerical relativistic hydrodynamics RHLLE and MUSTA-FORCE have been applied in simulations. To speed-up calculations, parallel processing has been made available for solving hydrodynamical equations. The test results of simulations for 3D, 2D and Bjorken expansion are reported in this paper. As a next step we plan to implement the hadronization algorithm by implementing the continuous particle emission for freeze-out and comparing it with Cooper-Frye formula.

Energy Technology Data Exchange (ETDEWEB)

We estimate the TeV {gamma}-ray fluxes expected from the population of young pulsars in terms of the self-consistent time-dependent hadronic-leptonic model for the high-energy processes inside the pulsar wind nebulae (PWNe). This radiation model is based on the hypothesis of Arons and collaborators who postulate that leptons are accelerated inside the nebulae as a result of resonant scattering on heavy nuclei, which in turn are accelerated in the pulsar wind region or the pulsar inner magnetosphere. Our aim is to find out which PWNe on the northern hemisphere are the best candidates for detection at energies above 60 GeV and 200 GeV by the next generation of low-threshold Cherenkov telescopes.

Energy Technology Data Exchange (ETDEWEB)

Inclusive double spin asymmetries obtained by scattering polarized electrons off polarized protons and deuterons have been analyzed to address the issue of quark-hadron duality in the polarized spin structure functions g^p_1 and g^d_1. A polarized electron beam, solid polarized NH_3 and ND_3 targets and the CEBAF Large Acceptance Spectrometer (CLAS) in Hall B were used to collect the data. The resulting g^p_1 and g^d_1 were averaged over the nucleon resonance energy region (M < W < 2.00 GeV), and three lowest lying resonances individually for tests of global and local duality.

International Nuclear Information System (INIS)

The proposed Superconducting Super Collider (SSC) in the US and plans for a Large Hadron Collider LHC at CERN are likely to require micron size filaments to reduce micron size filaments to reduce magnetization effects at the low injection fields envisioned. Superconductors of NbTi, designed to meet these requirements, are described. These conductors contain from 6000 to 36,613 filaments. Results are presented on NbTi conductors made by multiple extrusion techniques. Filament sizes of between 2.2 and 17 micron have been obtained. Current densities of between 2400 A/mm"2 and nearly 3400 A/mm"2 at 5 Tesla have been achieved. Metallurgical aspects of these conductors are presented using both optical and SEM views of conductor cross section and filament surface.

Energy Technology Data Exchange (ETDEWEB)

This Report includes copies of transparencies and notes from the presentations made at the Center for Accelerator Physics at Brookhaven National Laboratory Editing and changes to the authors` contributions in this Report were made only to fulfill the publication requirements. This volume includes notes and transparencies on nine presentations: ``The Energy Exchange and Efficiency Consideration in Klystrons``, ``Some Properties of Microwave RF Sources for Future Colliders + Overview of Microwave Generation Activity at the University of Maryland``, ``Field Quality Improvements in Superconducting Magnets for RHIC``, ``Hadronic B-Physics``, ``Spiking Pulses from Free Electron Lasers: Observations and Computational Models``, ``Crystalline Beams in Circular Accelerators``, ``Accumulator Ring for AGS & Recent AGS Performance``, ``RHIC Project Machine Status``, and ``Gamma-Gamma Colliders.``

CERN Document Server

Quartz fiber calorimetry is a technique the signal generation mechanism of which is based on the Cherenkov effect. In this article we try to give a comprehensive overview of the subject. We start with a general introduction to calorimetry where the basic elements that characterize the development of electromagnetic and hadronic showers are discussed. Then we describe in detail the operation principle and the properties of calorimeters equipped with quartz fibers. The main advantages of this type of calorimeters are the radiation hardness, the fast response and the compact detector dimensions, features that derive from the quartz material and the specific mechanism of operation. A section is devoted to presenting the quartz fiber calorimeters that have been built or planned to in various experiments to operate as centrality detectors, trigger detectors, luminosity monitors or general purpose very forward calorimeters.

International Nuclear Information System (INIS)

The RD50 collaboration has been exploring the development of radiation hard semiconductor devices for very high-luminosity colliders since 2002. The target fluence to qualify detectors set by the anticipated dose for the innermost tracking layers of the future upgrade of the CERN large hadron collider (LHC) is 1016 1 MeV neutron equivalent (neq) cm-2. This is about an order of magnitude higher than the maximum dose for the most exposed silicon detectors in the current machine. RD50 investigates the radiation hardening of silicon sensors from many angles: improvement of the intrinsic tolerance of the substrate material, optimisation of the readout geometry and study of novel design of detectors. A review of some of the recent activities within RD50 is here presented.

British Library Electronic Table of Contents (United Kingdom)

MINER?A is a high resolution, fully active detector designed to study neutrino interactions on nuclei in the NuMI beam at Fermi National Accelerator Laboratory. The active volume of the detector consists of 3 tons of plastic scintillator and includes embedded targets of 4He, C, H2O, Fe and Pb. The MINER?A collaboration expects to perform precision, A-dependent neutrino cross section measurements in the 1?10 GeV region, measure the axial form factor, and study nuclear shadowing of F2, quark-hadron duality and coherent pion production, among other topics. MINER?A began data taking in the fall of 2009. This paper describes the MINER?A experiment and provides an overview of the physics objectives along with estimated uncertainties of the measurements and the tentative projected schedule of dat...

Energy Technology Data Exchange (ETDEWEB)

Differential cross sections for dijet photoproduction in association with a leading neutron using the reaction e{sup +}+p{yields}e{sup +}+n+jet+jet+X{sub r} have been measured with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb{sup -1}. The fraction of dijet events with a leading neutron in the final state was studied as a function of the jet kinematic variables. The cross sections were measured for jet transverse energies E{sub T}{sup jet}>6 GeV, neutron energy E{sub n}>400 GeV, and neutron production angle {theta}{sub n}<0.8 mrad. The data are broadly consistent with factorization of the lepton and hadron vertices and with a simple one-pion-exchange model.

International Nuclear Information System (INIS)

The postulate that negative-energy particles do not exist (travelling forward in time) leads automatically to the 'Reinterpretation Principle' by Stueckelberg and by Feynman. It has been already shown that such a 'principle', assumed as the Third postulate of special relativity, ensures the validity of the law of (retarded) casuality both in standard relativity and in (extended) relativity with tachyons and with Superluminal inertial frames. Our Thir postulate, moreover, allows predicting antiparticle existence in a purely relativistic context. In this paper it is shown that the Third postulate is enough to implement the law of casuality even in macrophysics, when usual macro-objects interact with micro-tachyons and macrotachyons. To that aim, some tachyon kinematics is further developed, which can be useful even in understanding elementary-particle interactions (and may be hadron structure). Many other related problems are discussed.

Energy Technology Data Exchange (ETDEWEB)

A pillbox RF output window was developed for the L-band pulsed klystron for the Japanese Hadron Project (JHP) 1-GeV proton linac. The window was designed to withstand a peak RF power of 6 MW, where the pulse width is 600 {mu}sec and the repetition rate is 50 Hz. A high power model was fabricated using an alumina ceramic which has a low loss tangent of 2.5x10{sup -5}. A high power test was successfully performed up to a 113 kW RF average power with a 4 MW peak power, a 565 {mu}sec pulse width and a 50 Hz repetition rate. By extrapolating the data of this high power test, the temperature rise of the ceramic is estimated low enough at the full RF power of 6 MW. Thus this RF window is expected to satisfy the specifications of the L-band Klystron. (author).

Energy Technology Data Exchange (ETDEWEB)

Energy flows in deep inelastic electron-proton scattering are investigated at a centre-of-mass energy of 296 GeV for the range Q{sup 2}{>=}10 GeV{sup 2} using the ZEUS detector. A comparison is made between events with and without a large rapidity gap between the hadronic system and the proton direction. The energy flows, corrected for detector acceptance and resolution, are shown for these two classes of events in both the HERA laboratory frame and the Breit frame. From the differences in the shapes of these energy flows we conclude that QCD radiation is suppressed in the large-rapidity-gap events compared to the events without a large rapidity gap. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The {rvec n} + p {yields} d + {gamma} experiment under construction at LANSCE studies the weak interaction between neutrons and protons. The experiments will measure the directional dependence of the parity-violating {gamma}-ray asymmetry, A{sub {gamma}}, in the polarized cold neutron capture by para-hydrogen. The goal is to measure A{sub {gamma}} with uncertainty of 0.5 x 10{sup -8}, 10% of its predicted value. A{sub {gamma}} primarily isolates the {Delta}I = 1 component of the hadronic weak interaction and thus will determine the long-range weak pion-nucleon coupling constant H{sub {pi}}{sup 1}. The experiment is carefully designed for the LANSCE pulsed spallation neutron source to achieve the proposed statistical precision and to control systematic errors. We discuss the experiment and its status.

CERN Multimedia

LECTURE SERIES 14, 15, 17 January 2008 11:00 to 12:00 - Council Chamber, bldg. 503-1-001 Applications of accelerators to tumour therapy U. AMALDI, TERA Foundation & University of Milano Bicocca The first lecture is devoted to an historical review of the developments of the teletherapy techniques which make use of hadron beams and are collectively called "hadrontherapy". The main emphasis is on the use of protons and light ions, but also neutrons, pions and antiprotons are considered. The second lecture reviews the rationale behind the use of carbon ions in the treatment of radioresistant tumours and the results obtained both with proton and carbon ion beams on the 60 000 patients treated worldwide. The numbers of patients who would profit from hadrontherapy are presented together with the current landscape of running and planned hospital based centres. The main technical challenges set by this therapeutic modality are discussed in the third lecture together ...

Energy Technology Data Exchange (ETDEWEB)

A review of recent work in nuclear physics is presented. The paper gives a broad discussion of research goals in nuclear structure, quark-gluon degrees of freedom, quark-gluon plasma, symmetries, and rare decays. (DWL)

International Nuclear Information System (INIS)

Experimental results of nuclear reaction and radiative decay for A = 203 nuclides are evaluated. Adopted properties for all the nine isobars, Au, Hg, Tl, Pb, Bi, Po, At, Rn, Fr of mass 203 are presented. Nothing is yet known for "2"0"3Os. 96 refs.

Energy Technology Data Exchange (ETDEWEB)

The National Nuclear Data Center provides information on nuclear reactions, nuclear structure, and decay data, and is a part of the Nuclear Data Center Network, established to coordinate the compilation and dissemination of nuclear data on an international scale.

International Nuclear Information System (INIS)

The 1976 version of Nuclear Data Sheets for A = 99 (76Bu07) has been revised. Detailed level and decay schemes, arguments for J#pi# assignments, and experimental data are presented. copyright 1988 Academic Press, Inc.

International Nuclear Information System (INIS)

Evaluated nuclear structure and decay data for all nuclei within the A = 203 mass chain are presented. This work supersedes the earlier evaluation by S. Rab (1993Ra11), published in Nuclear Data Sheets 70, 173 (1993).

International Nuclear Information System (INIS)

64Cu (T1/2=12.7h, ?- decay: 40%, ?+ decay: 19%, E.C. decay: 41%) is one of the most useful radioisotope in the nuclear medicine due to its multiple decay mode and the intermediate half-life. Several nuclear reaction, i.e., 64Ni(p,n)64Cu, 68Zn(p,?n)64Cu and 64Ni(d,2n)64Cu have been investigated for production. The highest could be obtained with proton irradiation on the enriched 64Ni target. For mass and routine production, the 64Ni target fabrication using electroplating, the reliable chemical separation of 64Cu from the irradiated 64Ni target and the effective recovery process for the recycling of very expensive enriched material ($20,000/g) and so forth are absolutely necessary to be established. In this work, we report our mass production method of 64Cu with 64Ni and Cyclone-30 accelerator

International Nuclear Information System (INIS)

Microsecond pulse radiolysis of oxygenated aqueous solutions containing 0.02 mol dm"-"3 sodium formate and 2 mmol dm"-"3 phosphate buffer at pH 7 was used to generate superoxide anion radicals. The influence of some biologically important compounds upon the rate of O_2"."-"b"a"r decay as monitored spectrophotometrically in the range of 245-300 nm. Hematoporphyrin (HP), hemin C (HC), catalase (Cat), cobalt sulfophthalocyanine (CoTSPc) were studied. Among the investigated compounds only Cat was found to show a high catalytic efficiency towards the self-decay of O_2"."-"b"a"r. A red shift of 0_2"."-"b"a"r absorption band and slowing down of its decay were observed to take place by adding HP or CoTSPc to the solutions containing formate ions in excess. This effect is associated with the formation of a transient superoxo-complex. An appearance of an intermediate species with absorption maxima at 350 nm and half-life of about 2 s ...

International Nuclear Information System (INIS)

... v. 36(2) NUCLEAR PHYSICS AND RADIATION PHYSICS beta-minus decay

International Nuclear Information System (INIS)

The paper reports on the results of hydrodynamical simulations of the late phase of the common envelope stage of a binary consisting of a 2-solar mass red giant and a 1-solar mass main-sequence companion. The numerical results demonstrate that sufficient energy is released from the orbit to eject the mass within the common envelope without requiring the main-sequence companion to spiral into the white dwarf core of the red giant star. At the end of the simulation the orbital decay time scale increases rapidly to more than 160 yr. The long decay time scale reflects the removal of mass from the common envelope and its subsequent spin-up to near corotation. The ratio of the orbital decay time scale to the mass-loss time scale from the common envelope increases to more than 700, and the mass contained within the common envelope decreases to about 0.01 solar mass or less. It is argued that further orbital ...

Energy Technology Data Exchange (ETDEWEB)

This report describes mathematical predictions for the migration of radionuclides from an emplaced radioactive waste container. The model assumes a spherical-equivalent waste solid surrounded by backfill but neglects the effect of decay heat. 7 refs., 2 tabs. (TEM)

International Nuclear Information System (INIS)

Russian 2008 p. 244 Russian Federation Artemov, SV Yarmukhamedov,

International Nuclear Information System (INIS)

The thermoluminescence (TL), blue stimulated luminescence (BSL) and infrared stimulated luminescence (IRSL) signals of fluorapatite (originating from Durango, Mexico) were measured and found to exhibit strong anomalous fading (AF). The experimentally obtained OSL and IRSL decay curves were transformed into pseudo-linear modulated (pseudo-LM) decay curves. The resulting glow-curve shaped pseudo-LM decay curves were analyzed using a deconvolution analysis, similar to the one used for the glow-curve deconvolution (GCD) of TL glow-curves. It was found that the pseudo-LM OSL and IRSL decay curves consist of two components named fast and slow, respectively, and their individual contribution was estimated. The AF of the remnant TL, BSL and IRSL as a function of the storage time was fitted using the tunneling model equations and the fading rate g, in terms of percentage per decade was evaluated. According to ...

International Nuclear Information System (INIS)

The "8"8Y decay has been studied with the aim to discover emission of monohromatic positrons (MP). The "8"8Sr(d,2N) reaction was used for production of "8"8Y (#beta#"+, Tsub(1/2)=106.6 days) nuclides. The prismatic beta spectrometer has been used to measure spectra of electrons and positrons. No MPs have been found. The resulting upper bound for their emission rate turned out to be lower than theoretically expected one.

CERN Document Server

The CP violating processes J/psi-->K_S K_S and psi(2S)-->K_S K_S are searched for using samples of 58 million J/psi and 14 million psi(2S) events collected with the Beijing Spectrometer at the Beijing Electron Positron Collider. No signal is observed, and upper limits on the decay branching ratios are determined to be BR(J/psi-->K_S K_S) K_S K_S) < 4.6x10^{-6} at the 95% confidence level.

CERN Document Server

The phenomenon of time resonances (or explosions) can explain the exponential reduction of the energy, which is accompanied for the certain degree by slight fluctuations under some conditions in the range of the energy strongly overlapped compound-resonances. These resonant explosions correspond to formation of several highly-exited non-exponentially decaying nuclear clots (partial compound nuclei consisting of several small groups of projectile nucleons and targets). This paper is a continuation and expansion of theoretical authors' work, which is a more general self-consistent version of the time-evolution approach in comparison with the traditional Izumo-Araseki time compound-nucleus model.

CERN Document Server

The processes psi'-->p pbar pi^0 and psi'-->p pbar eta are studied using a sample of 14 million psi' decays collected with the Beijing Spectrometer at the Beijing Electron-Positron Collider. The branching fraction of psi'-->p pbar pi^0 is measured with improved precision as (13.2\\pm 1.0\\pm 1.5)\\times 10^{-5}, and psi'-->p pbar eta is observed for the first time with a branching fraction of (5.8\\pm 1.1\\pm 0.7)\\times 10^{-5}, where the first errors are statistical and the second ones are systematic.

International Nuclear Information System (INIS)

Evaluated spectroscopic data for all nuclei with mass number A = 177 and corresponding level schemes from radioactive decay and reaction studies are presented. Most of the new information since the previous evaluation of this mass chain consists of the decay of the recently discovered isotope "1"7"7Tm, and the level structure of "1"7"7Ir, "1"7"7Os, and "1"7"7Pt. The present evaluation supersedes the earlier one by Y. A. Ellis and B. Harmatz (75E107) published in Nuclear Data Sheets 16, 135 (1975).

British Library Electronic Table of Contents (United Kingdom)

LUCIFER (Low-background Underground Cryogenic Installation For Elusive Rates) is a new project for the study of neutrinoless Double Beta Decay, based on the technology of scintillating bolometers. These devices promise a very efficient rejection of the alpha background, opening the way to a virtual background-free experiment if candidates with a transition energy higher than 2615 keV are investigated. The baseline candidate for LUCIFER is 82Se. This isotope will be embedded in ZnSe crystals grown with enriched selenium and operated as scintillating bolometers in a low-radioactivity underground dilution refrigerator. In this paper, the LUCIFER concept will be introduced. The sensitivity and the very promising prospects related to this project will be discussed.

International Nuclear Information System (INIS)

The #gamma#-radiation following thermal neutron capture in "1"0"0Mo has been studied by singles and coincidence measurements. A "1"0"1Mo level scheme has been deduced and is compared with the results of previous (d,p), (n,#gamma#) and "1"0"1Nb decay studies. The existence of the first excited state at 13.51 keV has been confirmed. The present data yield a neutron binding energy of 5398.4 KeV. (Auth.).

CERN Document Server

We investigate stability properties of indirectly damped systems of evolution equations in Hilbert spaces, under new compatibility assumptions. We prove polynomial decay for the energy of solutions and optimize our results by interpolation techniques, obtaining a full range of power-like decay rates. In particular, we give explicit estimates with respect to the initial data. We discuss several applications to hyperbolic systems with {\\em hybrid} boundary conditions, including the coupling of two wave equations subject to Dirichlet and Robin type boundary conditions, respectively.

CERN Document Server

We provide a scenario in which a hidden U(1) gauge boson constitutes dark matter of the Universe and decays into the standard-model particles through a kinetic mixing with an $U(1)_{B-L}$ gauge boson. Interestingly, our model can naturally account for the steep rise in the positron fraction recently reported by PAMELA. Moreover, we find that due to the charge assignment of $U(1)_{B-L}$, only a small amount of antiprotons are produced in the decay, which is also consistent with the PAMELA and other observational data.

International Nuclear Information System (INIS)

In this work, the half-lives of the beta-unstable nuclei "1"0"1Mo and "1"0"1Tc were studied using neutron-irradiated samples of "1"0"0Mo to produce "1"0"1Mo which in its turn generates "1"0"1Tc by beta decay. The gamma activity of each sample was followed for 5 consecutive half-lives in steps of 5 minutes. A total of 22 sources were measured and checked for dead-time influence, and the half-lives were obtained by weighted average. The results are statistically incompatible with the tabulated values.

Energy Technology Data Exchange (ETDEWEB)

Neutron deficient nuclei with mass numbers A {approx} 90 and 40 {<=} Z {<=} 44 have been studied making use of the Osiris and Nordball spectrometers. The high spin states of these nuclei and their electromagnetic decay properties are compared to shell model calculations based on the core {sup 88}Sr and using different parametrizations of the residual interaction. The dependence of the mean square deviations of experimental and theoretical level energies, branching ratios, and transition probabilities on the neutron numbers N = 46-50 and the validity of seniority as a good quantum number are discussed. (orig.).

International Nuclear Information System (INIS)

In the reactions induced by heavy ions, the study of breakup of heavy ions followed by the fusion of one of the fragments with the target has been of great interest. The present experiments has been performed with a view to compare the measured excitation functions for the same decay channels in "1"2C + "1"6"5Ho and "1"4N + "1"6"3Dy systems

CERN Document Server

We entertain the idea that a suitable background of cold (very low momentum) pseudoscalar particles or condensate, may trigger a background that effectively generates Lorentz-invariance violation. This aether-like background induces a Chern-Simons modification of QED. Physics is different in different frames and, in the rest frame of the pseudoscalar background, high momentum photons can decay into pairs. The threshold for such decay depends quadratically on the rest mass of the particles. This mechanism could explain in a natural way why antiprotons are absent in recent cosmic ray measurements. A similar signal could be used as a probe of pseudoscalar condensation in heavy ion collisions.

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Combustion in a ceramic tube produces a nearly discontinuous change in temperature of the premixed fuel and air at the flame front, from room temperature up to the adiabatic flame temperature ([approximately]2,100 K). The upstream Reynolds number for a stable flame in a 9.5-mm tube is in the range of 3,000-6,000, corresponding to turbulent flow. Owing to property changes that accompany the severe increase in temperature at the flame front, the downstream Reynolds number is reduced below the transitional value ([approximately]2,100); consequently the turbulence decays while the velocity profile approaches the parabolic one characteristic of laminar flow. A previous study of ours revealed that, far downstream from the flame front, the turbulent energy decayed exponentially with downstream distance. This paper examines the asymptotic behavior of the k-[epsilon] model and compares the results to that for two-dimensional (axisymmetric) disturbances ...

International Nuclear Information System (INIS)

We investigate the possibility of kaon condensation in the dense interior of neutron stars through the s-wave interaction of kaons with nucleons. We include nucleon-nucleon interactions by using simple parametrizations of realistic forces, and include electrons and muons in #beta#-equilibrium. The equation of state above the condensate threshold is derived in the mean field approximation. The conditions under which kaon condensed cores undergo a transition to quark matter containing strange quarks are also established.The critical density for kaon condensation lies in the range (2.3-5.0)#rho#_0, where #rho#_0=0.16 fm"-"3 is the equilibrium density of nuclear matter. The critical density depends largely on the value of the strangeness content of the proton, the size of which is controversial. For too large a value of the strangeness content, matter with a kaon condensate is not sufficiently stiff to support the lower limit of 1.44 M_o_e_d_o_t for a neutron star. Kaon condensation ...

UK PubMed Central (United Kingdom)

Dissecting the genes involved in complex traits can be confounded by multiple factors, including extensive epistatic interactions among genes, the involvement of epigenetic regulators, and the variable...Full Text Available

UK PubMed Central (United Kingdom)

Recently, we demonstrated that the central ghrelin signalling system, involving the ghrelin receptor (GHS-R1A), is important for alcohol reinforcement. Ghrelin targets a key mesolimbic circuit involved...Full Text Available

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Klebsiella pneumoniae is able to grow anaerobically with citrate as a sole carbon and energy source by a fermentative pathway involving the Na⁺-dependent citrate...Full Text Available

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The incidence of arrhythmias after acute myocardial infarction of the inferior wall varies with the affected segment and increases when there is right ventricular involvement. This paper provides a...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe MYC transcription factors are known to be involved in the biology of many human cancer types. But little is known about the Myc/microRNAs cooperation in the regulation...Full Text Available

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Information Technology Glossary of Terms. Applets: Programs that run inside net browsers, usually in Java and typically involving modestly interactive ...

International Nuclear Information System (INIS)

A case of metastatic Ewing's sarcoma to the skull is presented, demonstrating the superiority of magnetic resonance imaging over other imaging modalities to exclude CNS involvement. Precise delineation of different tumor components in extradural location contained in an intact dural rim together with compressed cortex showing no signs of tumorous involvement constituted an MRI appearance allowing us to exclude tumor outgrowth into the brain. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Decay mechanism of H{sub 2}{sup -} anions produced by {gamma}-ray or X-ray radiolysis of solid para-H{sub 2} (p-H{sub 2}) has been studied using high-resolution ESR spectroscopy in the temperature range between 2.7-6.6 K. The results can be summarized as follows; First, the decay rate constant of the H{sub 2}{sup -} anion is not proportional to initial yields of reactive species such as H radical and cation but proportional to concentrations of HD and D{sub 2} impurities in p-H{sub 2}. Second, ESR spectra assigned as electron bubbles were observed in solid p-H{sub 2} containing large amount of HD or D{sub 2} (11 mol %), while they were not observed in pure solid p-H{sub 2}. Third, the decay rate constant of the H{sub 2}{sup -} anion increases with the decrease in temperature between 2.7-5 K, while it decreases with the decrease between 5-6.6 K. Fourth, the decay of the H{sub 2}{sup -} anion is ...

CERN Document Server

First results are presented from an analysis of data from the DRIFT-IIa and DRIFT-IIb directional dark matter detectors at Boulby Mine in which alpha particle tracks were reconstructed and used to characterise detector performance--an important step towards optimising directional technology. The drift velocity in DRIFT-IIa was [59.3 +/- 0.2 (stat) +/- 7.5 (sys)] m/s based on an analysis of naturally-occurring alpha-emitting background. The drift velocity in DRIFT-IIb was [57 +/- 1 (stat) +/- 3 (sys)] m/s determined by the analysis of alpha particle tracks from a Po-210 source. 3D range reconstruction and energy spectra were used to identify alpha particles from the decay of Rn-222, Po-218, Rn-220 and Po-216. This study found that (22 +/- 2)% of Po-218 progeny (from Rn-222 decay) are produced with no net charge in 40 Torr CS2. For Po-216 progeny (from Rn-220 decay) the uncharged fraction is (100 +0 -35)%.

Energy Technology Data Exchange (ETDEWEB)

We revisited the quantum Zeno paradox, which claims that a generic quantum system prepared in a state which is not an eigenstate of the Hamiltonian operator and is continuously observed never decays. Since any perfectly isolated quantum system always interact with a vacuum field, we analyze the possibility of using this fact to solve the above mentioned conceptual problem. Therefore we discuss a two-level system or qubit-Bose field interaction Hamiltonians. We consider the quantum dynamics of this two-level system, prepared in the excited state interacting with a Bose field prepared in the Poincare invariant vacuum state. Using a first-order approximation in time-dependent perturbation theory, we evaluate the probability of spontaneous decay of the two-level system driven by the vacuum field. This probability is evaluated for a finite time interval. Using the standard argument to obtain the quantum Zeno paradox, we consider N measurements where ...

CERN Document Server

Utilizing form factors calculated within the light-cone sum rules, we have evaluated the decay branching ratios of $B_s\\to \\phi\\gamma$ and $B_s\\to \\phi \\ell^+\\ell^-$ in a single universal extra dimension model (UED), which is viewed as one of the alternative theories beyond the standard model (SM). For the decay $B_s \\to \\phi \\ell^+\\ell^-$, the dilepton invariant mass spectra, the forward-backward asymmetry, and double lepton polarization are also calculated. For each case, we compared the obtained results with predictions of the SM. In lower values of the compactification factor 1/R, the only parameter in this model, we see the considerable discrepancy between the UED and SM models. However, when 1/R increases, the results of UED tend to diminish and at $1/R = 1000 \\mathrm{GeV}$, two models have approximately the same predictions. Compared with data from CDF of $B_s \\to \\phi \\mu^+ \\mu^-$, the 1/R tends to be larger than $350 ...

CERN Document Server

We study the Sunyaev-Zel'dovich (SZ) effect potentially generated by relativistic electrons injected from dark matter (DM) annihilation or decay in the Galaxy, and check whether it could be observed by Planck or ALMA, or even imprint the current CMB data as e.g. the specific fluctuation excess claimed from an recent re-analysis of the WMAP-5 data. We focus on high-latitude regions to avoid contamination of the Galactic astrophysical electron foreground, and consider the annihilation or decay coming from the smooth DM halo as well as from subhalos, further extending our analysis to a generic modeling of spikes arising around intermediate-mass-black-holes (IMBHs). We show that all these dark Galactic components are unlikely to produce any observable SZ effect. For a self-annihilating DM particle of 10 GeV with canonical properties, the largest optical depth we find is $\\tau_e \\lesssim 10^{-7}$ for massive isolated subhalos hosting IMBHs. We ...

Science.gov (United States)

The 10.3-h /sup 165/Er, decaying by electron capture to stable /sup 165/Ho, offers an excellent promise for use in diagnostic nuclear medicine, especially in conjuction with multiwire proportional-counter cameras. Using an ultra-high-resolution Si(Li) photon spectrometer, L and K x-ray photon yields in /sup 165/Er decay have been measured. The ratio P/sub L//P/sub K/ of electron-capture probabilities in L and K shells is determined to be 0.196 +- 0.030, in good agreement with theory. Estimates of Auger electron yields and yields of very-low-energy electrons from Coster--Kronig transitions are presented. Levels of /sup 169/Er and /sup 171/Er radioactive impurities in the reactor-produced /sup 165/Er sample are experimentally determined. Whole-body dose estimates for /sup 165/Er are given. These compare favorably with /sup 99/Tc dose.

CERN Document Server

We investigate the possibility of producing the $\\omega\\phi$ threshold enhancement recently observed in the $J\\psi\\to\\gamma X(1812),~X(1812)\\to\\omega\\phi$ at BES by assuming the X(1812) to be a candidate of $(K^{*}\\bar K^{*0})$ molecular state. We evaluate the decay rate of $X(1812)\\to\\eta\\eta', \\eta\\eta, \\omega\\phi, K^+K^-, \\rho^+\\rho^-$, $\\omega\\omega, K^{*+}K^{*-}$ and $\\pi^+\\pi^-$ based on the X(1812) to be a candidate of $(\\ksks)$ molecule. It turns out the X(1812) dominantly decays into $\\eta\\eta'$ and $\\eta\\eta$. These channels are suggested to be the laboratory to test the molecular scenario in experiment. We also evaluate the branching fraction $Br(X\\to\\omega\\phi)\\simeq 4.60%$. However, the X(1812) has small branching fractions to decay into other $VV$ or $PP$ final states, from which it seems to be consistent with the experimental observation. In the molecular scenario, the X(1812) ...

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