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1

Micromegas readouts for double beta decay searches  

E-Print Network (OSTI)

Double beta $\\beta\\beta$ decay experiments are one of the most active research topics in Neutrino Physics. The measurement of the neutrinoless mode $0\

Cebrián, S; Ferrer-Ribas, E; Galán, J; García, J A; Giomataris, I; Gómez, H; Herrera, D C; Iguaz, F J; Irastorza, I G; Luzón, G; Rodríguez, A; Seguí, L; Tomás, A

2010-01-01T23:59:59.000Z

2

Micromegas readouts for double beta decay searches  

E-Print Network (OSTI)

Double beta $\\beta\\beta$ decay experiments are one of the most active research topics in Neutrino Physics. The measurement of the neutrinoless mode $0\

S. Cebrián; T. Dafni; E. Ferrer-Ribas; J. Galán; J. A. García; I. Giomataris; H. Gómez; D. C. Herrera; F. J. Iguaz; I. G. Irastorza; G. Luzón; A. Rodríguez; L. Seguí; A. Tomás

2010-09-09T23:59:59.000Z

3

Neutrinoless double beta decay and neutrino masses  

SciTech Connect

Neutrinoless double beta decay (0{nu}{beta}{beta}) is a promising test for lepton number violating physics beyond the standard model (SM) of particle physics. There is a deep connection between this decay and the phenomenon of neutrino masses. In particular, we will discuss the relation between 0{nu}{beta}{beta} and Majorana neutrino masses provided by the so-called Schechter-Valle theorem in a quantitative way. Furthermore, we will present an experimental cross check to discriminate 0{nu}{beta}{beta} from unknown nuclear background using only one isotope, i.e., within one experiment.

Duerr, Michael [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)

2012-07-27T23:59:59.000Z

4

Scintillating bolometers for Double Beta Decay search  

E-Print Network (OSTI)

In the field of Double Beta Decay (DBD) searches, the use of high resolution detectors in which background can be actively discriminated is very appealing. Scintillating bolometers containing a Double Beta Decay emitter can largely fulfill this very interesting possibility. In this paper we present the latest results obtained with CdWO4 and CaMoO4 crystals. Moreover we report, for the first time, a very interesting feature of CaMoO4 bolometers: the possibility to discriminate beta-gamma events from those induced by alpha particles thanks to different thermal pulse shape.

Gironi, Luca

2009-01-01T23:59:59.000Z

5

Scintillating bolometers for Double Beta Decay search  

E-Print Network (OSTI)

In the field of Double Beta Decay (DBD) searches, the use of high resolution detectors in which background can be actively discriminated is very appealing. Scintillating bolometers containing a Double Beta Decay emitter can largely fulfill this very interesting possibility. In this paper we present the latest results obtained with CdWO4 and CaMoO4 crystals. Moreover we report, for the first time, a very interesting feature of CaMoO4 bolometers: the possibility to discriminate beta-gamma events from those induced by alpha particles thanks to different thermal pulse shape.

Luca Gironi

2009-11-05T23:59:59.000Z

6

The double-beta decay: Theoretical challenges  

Science Conference Proceedings (OSTI)

Neutrinoless double beta decay is a unique process that could reveal physics beyond the Standard Model of particle physics namely, if observed, it would prove that neutrinos are Majorana particles. In addition, it could provide information regarding the neutrino masses and their hierarchy, provided that reliable nuclear matrix elements can be obtained. The two neutrino double beta decay is an associate process that is allowed by the Standard Model, and it was observed for about ten nuclei. The present contribution gives a brief review of the theoretical challenges associated with these two process, emphasizing the reliable calculation of the associated nuclear matrix elements.

Horoi, Mihai [Department of Physics, Central Michigan University, Mount Pleasant, Michigan, 48859 (United States)

2012-11-20T23:59:59.000Z

7

Search for ? + / EC double beta decay of 120 Te  

Science Conference Proceedings (OSTI)

We present a search for ? + / EC double beta decay of 120 Te performed with the CUORICINO experiment

C. Tomei; The CUORICINO Collaboration

2011-01-01T23:59:59.000Z

8

A background free double beta decay experiment  

E-Print Network (OSTI)

We present a new detection scheme for rejecting backgrounds in neutrino less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is a high-pressure 136Xe emitter for which the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is to use the Spherical Proportional Counter that provides two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of their higher density, the considered process is out of energy range. An alternative solution could be the development of double decay emitters with lower density by using for instance the aerogel technique. It is surprising that a technology used for particle identification in high-energy physics becomes a powerful tool for rejecting backgrounds in such low-energy experiments.

Ioannis Giomataris

2010-12-20T23:59:59.000Z

9

Nuclear physics aspects of double beta decay  

E-Print Network (OSTI)

Comprehensive description of the phenomenology of the $\\beta\\beta$ decay is given, with emphasis on the nuclear physics aspects. After a brief review of the neutrino oscillation results and of motivation to test the lepton number conservation, the mechanism of the $0\

Petr Vogel

2008-07-15T23:59:59.000Z

10

Double Beta Decay: Historical Review of 75 Years of Research  

E-Print Network (OSTI)

Main achievements during 75 years of research on double beta decay have been reviewed. The existing experimental data have been presented and the capabilities of the next-generation detectors have been demonstrated.

A. S. Barabash

2011-04-14T23:59:59.000Z

11

Neutrino-less Double Beta Decay and Particle Physics  

E-Print Network (OSTI)

We review the particle physics aspects of neutrino-less double beta decay. This process can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). The physics potential of both interpretations is summarized and the consequences of future measurements or improved limits on the half-life of neutrino-less double beta decay are discussed. We try to cover all proposed alternative realizations of the decay, including light sterile neutrinos, supersymmetric or left-right symmetric theories, Majorons, and other exotic possibilities. Ways to distinguish the mechanisms from one another are discussed. Experimental and nuclear physics aspects are also briefly touched, alternative processes to double beta decay are discussed, and an extensive list of references is provided.

Werner Rodejohann

2011-06-07T23:59:59.000Z

12

Searching for Double Beta Decay with the Enriched Xenon Observatory  

Science Conference Proceedings (OSTI)

The Enriched Xenon Observatory (EXO) Collaboration is building a series of experiments to search for the neutrinoless double beta decay of {sup 136}Xe. The first experiment, known as EXO-200, will utilize 200 kg of xenon enriched to 80% in the isotope of interest, making it the largest double beta decay experiment to date by one order of magnitude. This experiment is rapidly being constructed, and will begin data taking in 2007. The EXO collaboration is also developing a technique to identify on an event-by-event basis the daughter barium ion of the double beta decay. If successful, this method would eliminate all conventional radioactive backgrounds to the decay, resulting in an ideal experiment. We summarize here the current status of EXO-200 construction and the barium tag R&D program.

Hall, C.; /SLAC

2007-03-16T23:59:59.000Z

13

Sensitivity of CUORE to Neutrinoless Double-Beta Decay  

SciTech Connect

In this paper, we study the sensitivity of CUORE, a bolometric double-beta decay experiment under construction at the Laboratori Nazionali del Gran Sasso in Italy. Two approaches to the computation of experimental sensitivity are discussed and compared, and the formulas and parameters used in the sensitivity estimates are provided. Assuming a background rate of 10{sup -2} cts/(keV kg y), we find that, after 5 years of live time, CUORE will have a 1#27;{sigma} sensitivity to the neutrinoless double-beta decay half-life of {caret T{sup 0{nu}}{sub 1/2}}(1{sigma}#27;) = 1.6x#2;10{sup 26} y and thus a potential to probe the effective Majorana neutrino mass down to 41-95 meV; the sensitivity at 1.64{sigma}#27;, which corresponds to 90% C.L., will be {caret T{sup 0{nu}}{sub 1/2}(1.64{sigma}#27;}) = 9.5x10{sup 25} y. This range is compared with the claim of observation of neutrinoless double-beta decay in {sup 76}Ge and the preferred range in the neutrino mass parameter space from oscillation results.

CUORE; Alessandria, F.; Andreotti, E.; Ardito, R.; Arnaboldi, C.; Avignone III, F. T.; Balata, M.; Bandac, I.; Banks, T. I.; Bari, G.; Beeman, J.; Bellini, F.; Bersani, A.; Biassoni, M.; Bloxham, T.; Brofferio, C.; Bryant, A.; Bucci, C.; Cai, X. Z.; Canonica, L.; Capelli, S.; Carbone, L.; Cardani, L.; Carrettoni, M.; Casali, N.; Chott, N.; Clemenza, M.; Cosmelli, C.; Cremonesi, O.; Creswick, R. J.; Dafinei, I.; Dally, A.; Biasi, A. De; Decowski, M. P.; Deninno, M. M.; Waard, A. de; Domizio, S. Di; Ejzak, L.; Faccini, R.; Fang, D. Q.; Farach, H. A.; Ferri, E.; Ferroni, F.; Fiorini, E.; Foggetta, L.; Franceschi, M. A.; Freedman, S. J.; Frossati, G.; Fujikawa, B. K.; Giachero, A.; Gironi, L.; Giuliani, A.; Gorla, P.; Gotti, C.; Guardincerri, E.; Gutierrez, T. D.; Haller, E. E.; Han, K.; Heeger, K. M.; Huang, H. Z.; Ichimura, K.; Kadel, R.; Kazkaz, K.; Keppel, G.; Kogler, L.; Kolomensky, Yu. G.; Kraft, S.; Lenz, D.; Li, Y. L.; Liu, X.; Longo, E.; Ma, Y. G.; Maiano, C.; Maier, G.; Maino, M.; Mancini, C.; Martinez, C.; Martinez, M.; Maruyama, R. H.; Moggi, N.; Morganti, S.; Napolitano, T.; Newman, S.; Nisi, S.; Nones, C.; Norman, E. B.; Nucciotti, A.; Orio, F.; Orlandi, D.; Ouellet, J. L.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pedretti, M.; Pessina, G.; Pirro, S.; Previtali, E.; Rampazzo, V.; Rimondi, F.; Rosenfeld, C.; Rusconi, C.; Salvioni, C.; Sangiorgio, S.; Schaeffer, D.; Scielzo, N. D.; Sisti, M.; Smith, A. R.; Stivanello, F.; Taffarello, L.; Terenziani, G.; Tian, W. D.; Tomei, C.; Trentalange, S.; Ventura, G.; Vignati, M.; Wang, B. S.; Wang, H. W.; Whitten Jr., C. A.; Wise, T.; Woodcraft, A.; Xu, N.; Zanotti, L.; Zarra, C.; Zhu, B. X.; Zucchelli, S.

2011-11-23T23:59:59.000Z

14

Efficient double beta decay nuclear matrix elements computations  

SciTech Connect

We have developed a shell model code for the accurate computation of the two-body matrix elements of the transition operators involved in the neutrinoless double beta decay. This code features coupled cluster method short-range correlations with Jastrow-like functions, finite nucleon size effect and higher order nucleon current corrections. We present the results obtained for {sup 48}Ca and {sup 82}Se, then we compare them with other results in the literature. In the case of {sup 48}Ca, we also study the contributions of the included effects and find good agreement with other published results.

Neacsu, Andrei [Horia Hulubei Foundation (FHH) 407 Atomistilor, Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH) 30 Reactorului, Magurele-Bucharest 077125 (Romania)

2012-11-20T23:59:59.000Z

15

Experimental study of double-{beta} decay modes using a CdZnTe detector array  

SciTech Connect

An array of sixteen 1 cm{sup 3} CdZnTe semiconductor detectors was operated at the Gran Sasso Underground Laboratory (LNGS) to further investigate the feasibility of double-{beta} decay searches with such devices. As one of the double-{beta} decay experiments with the highest granularity the 4x4 array accumulated an overall exposure of 18 kg days. The setup and performance of the array is described. Half-life limits for various double-{beta} decay modes of Cd, Zn, and Te isotopes are obtained. No signal has been found, but several limits beyond 10{sup 20} years have been performed. They are an order of magnitude better than those obtained with this technology before and comparable to most other experimental approaches for the isotopes under investigation. An improved limit for the {beta}{sup +}/EC decay of {sup 120}Te is given.

Dawson, J. V. [Laboratoire Astroparticule et Cosmologie, 10 rue Alice Domon et Leonie Duquet, F-75205 Paris (France); Goessling, C.; Koettig, T.; Muenstermann, D.; Rajek, S.; Schulz, O. [Lehrstuhl fuer Experimentelle Physik IV, Technische Universitaet Dortmund, Otto-Hahn Str. 4, D-44227 Dortmund (Germany); Janutta, B.; Zuber, K. [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden, Zellescher Weg 19, D-01069 Dresden (Germany); Junker, M. [Laboratori Nazionali del Gran Sasso, Assergi (Italy); Reeve, C. [University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom); Wilson, J. R. [University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom)

2009-08-15T23:59:59.000Z

16

Neutron Interactions in the CUORE Neutrinoless Double Beta Decay Experiment  

SciTech Connect

Neutrinoless double beta decay (0{nu}DBD) is a lepton-number violating process that can occur only for a massive Majorana neutrino. The search for 0{nu}DBD is currently the only practical experimental way to determine whether neutrinos are identical to their own antiparticles (Majorana neutrinos) or have distinct particle and anti-particle states (Dirac neutrinos). In addition, the observation of 0{nu}DBD can provide information about the absolute mass scale of the neutrino. The Cuoricino experiment was a sensitive search for 0{nu}DBD, as well as a proof of principle for the next generation experiment, CUORE. CUORE will search for 0{nu}DBD of {sup 130}Te with a ton-scale array of unenriched TeO{sub 2} bolometers. By increasing mass and decreasing the background for 0{nu}DBD, the half-life sensitivity of CUORE will be a factor of twenty better than that of Cuoricino. The site for both of these experiments is the Laboratori Nazionali del Gran Sasso, an underground laboratory with 3300 meters water equivalent rock overburden and a cosmic ray muon attenuation factor of 10{sup -6}. Because of the extreme low background requirements for CUORE, it is important that all potential sources of background in the 0{nu}DBD peak region at 2530 keV are well understood. One potential source of background for CUORE comes from neutrons, which can be produced underground both by ({alpha},n) reactions and by fast cosmic ray muon interactions. Preliminary simulations by the CUORE collaboration indicate that these backgrounds will be negligible for CUORE. However, in order to accurately simulate the expected neutron background, it is important to understand the cross sections for neutron interactions with detector materials. In order to help refine these simulations, I have measured the gamma-ray production cross sections for interactions of neutrons on the abundant stable isotopes of Te using the GEANIE detector array at the Los Alamos Neutron Science Center. In addition, I have used the GEANIE data to set an upper limit for the production of a 2529 keV gamma-ray from the {sup 126}Te(n,n{prime}{gamma}) reaction. This gamma-ray is a potential source of interference for the 0{nu}DBD peak. Based on this measurement, the contribution of this line to the background is expected to be negligible.

Dolinski, M J

2008-09-24T23:59:59.000Z

17

Observation of Two-Neutrino Double-Beta Decay in Xe-136 with EXO-200  

SciTech Connect

We report the observation of two-neutrino double-beta decay in {sup 136}Xe with T{sub 1/2} = 2.11 {+-} 0.04(stat) {+-} 0.21(syst) x 10{sup 21} yr. This second-order process, predicted by the standard model, has been observed for several nuclei but not for {sup 136}Xe. The observed decay rate provides new input to matrix element calculations and to the search for the more interesting neutrinoless double-beta decay, the most sensitive probe for the existence of Majorana particles and the measurement of the neutrino mass scale.

Ackerman, N.; /SLAC; Aharmim, B.; /Laurentian U.; Auger, M.; /Bern U.; Auty, D.J.; /Alabama U.; Barbeau, P.S.; Barry, K.; Bartoszek, L.; /Stanford U., Phys. Dept.; Beauchamp, E.; /Laurentian U.; Belov, V.; /Moscow, ITEP; Benitez-Medina, C.; /Colorado State U.; Breidenbach, M.; /SLAC; Burenkov, A.; /Moscow, ITEP; Cleveland, B.; /Laurentian U.; Conley, R.; Conti, E.; /SLAC; Cook, J.; /Massachusetts U., Amherst; Cook, S.; /Colorado State U.; Coppens, A.; /Carleton U.; Counts, I.; /Stanford U., Phys. Dept.; Craddock, W.; /SLAC; Daniels, T.; /Massachusetts U., Amherst /Moscow, ITEP /Maryland U. /Stanford U., Phys. Dept. /Alabama U. /Maryland U. /Moscow, ITEP /Stanford U., Phys. Dept. /Laurentian U. /Carleton U. /Colorado State U. /Laurentian U. /Munich, Tech. U. /Bern U. /SLAC /Bern U. /Carleton U. /Stanford U., Phys. Dept. /Carleton U. /Maryland U. /Colorado State U. /SLAC /Carleton U. /SLAC /Alabama U. /SLAC /Moscow, ITEP /Indiana U. /Stanford U., Phys. Dept. /Moscow, ITEP /Stanford U., Phys. Dept. /Massachusetts U., Amherst /Seoul U. /Carleton U. /Stanford U., Phys. Dept.; /more authors..

2012-09-14T23:59:59.000Z

18

Challenges for a reliable shell model description of the neutrinoless double beta decay matrix elements  

SciTech Connect

Assuming that the neutrinos are Majorana particles and the neutrinoless double beta (0{nu}{beta}{beta}) decay is observed, a reliable 0{nu}{beta}{beta} matrix element is necessary to decide the neutrino mass hierarchy and the minimum neutrino mass. Many nuclear structure techniques, including the shell model, are presently used to calculate these matrix elements. In the last few years one could see a slow convergence of these results, but not yet at a level of 20 several shell model effective interactions and varying other parameters, finding results in a range that spans about 20In this contribution we describe challenges for obtaining reliable shell model 0{nu}{beta}{beta} matrix elements, with emphasis to {sup 76}Ge and {sup 82}Se decays.

Horoi, Mihai [Department of Physics, Central Michigan University, Mount Pleasant, Michigan, 48859 (United States)

2011-12-16T23:59:59.000Z

19

Optimization of the Transport Shield for Neutrinoless Double Beta-decay Enriched Germanium  

SciTech Connect

This document presents results of an investigation of the material and geometry choice for the transport shield of germanium, the active detector material used in 76Ge neutrinoless double beta decay searches. The objective of this work is to select the optimal material and geometry to minimize cosmogenic production of radioactive isotopes in the germanium material. The design of such a shield is based on the calculation of the cosmogenic production rate of isotopes that are known to cause interfering backgrounds in 76Ge neutrinoless double beta decay searches.

Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.; Reid, Douglas J.; Fast, James E.

2012-04-15T23:59:59.000Z

20

New limit on the neutrinoless double beta decay of /sup 100/Mo  

SciTech Connect

A search for the neutrinoless double beta decay of /sup 100/Mo was conducted using thin Mo films and solid state Si detectors. The experiment has collected 3500 hours of data operating underground in a deep silver mine (3290 M.W.E.). Only one event was found to be consistent with neutrinoless double beta decay. Using this one event, a limit of greater than or equal to 1 x 10/sup 22/ years (1 sigma) is set on the /sup 100/Mo half-life. This is approximately five times larger than the best previous /sup 100/Mo limit.

Krivicich, J.M.

1988-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

The NEXT experiment: A high pressure xenon gas TPC for neutrinoless double beta decay searches  

E-Print Network (OSTI)

Neutrinoless double beta decay is a hypothetical, very slow nuclear transition in which two neutrons undergo beta decay simultaneously and without the emission of neutrinos. The importance of this process goes beyond its intrinsic interest: an unambiguous observation would establish a Majorana nature for the neutrino and prove the violation of lepton number. NEXT is a new experiment to search for neutrinoless double beta decay using a radiopure high-pressure xenon gas TPC, filled with 100 kg of Xe enriched in Xe-136. NEXT will be the first large high-pressure gas TPC to use electroluminescence readout with SOFT (Separated, Optimized FuncTions) technology. The design consists in asymmetric TPC, with photomultipliers behind a transparent cathode and position-sensitive light pixels behind the anode. The experiment is approved to start data taking at the Laboratorio Subterr\\'aneo de Canfranc (LSC), Spain, in 2014.

D. Lorca; J. Martín-Albo; F. Monrabal; for the NEXT Collaboration

2012-10-15T23:59:59.000Z

22

Calorimeter R&D for the SuperNEMO Double Beta Decay Experiment  

E-Print Network (OSTI)

SuperNEMO is a next-generation double beta decay experiment based on the successful tracking plus calorimetry design approach of the NEMO3 experiment currently running in the Laboratoire Souterrain de Modane (LSM). SuperNEMO can study a range of isotopes, the baseline isotopes are 82Se and possibly 150Nd. The total isotope mass will be 100-200 kg. A sensitivity to neutrinoless double beta decay half-life greater than 10e26 years can be reached which gives access to Majorana neutrino masses of 50-100 meV. One of the main challenges of the SuperNEMO R&D is the development of the calorimeter with an unprecedented energy resolution of 4% FWHM at 3 MeV (Qbb value of 82Se).

Matthew Kauer; for the SuperNEMO Collaboration

2008-07-14T23:59:59.000Z

23

Neutrino-less Double Beta Decay of {sup 48}Ca-CANDLES  

Science Conference Proceedings (OSTI)

Neutrino-less double beta decay (0{nu}{beta}{beta}) is currently known to be an only experiment to verify whether lepton number is conserved or not. The lepton number non-conservation is the key to create matter dominated universe with CP violation. The so-called leptogenesys scenario presents a way to create the matter dominated universe by these violations. If neutrinos have Majorana mass, transition from a particle to an anti-particle is possible and the left-handed and right-handed neutrinos could have different masses. It is highly likely that the neutrinos are Majorana particles. We have been studying double beta decay of {sup 48}Ca. Our first stage experiment using the ELEGANT VI detector system gave the best lower limit of the half life of 0{nu}{beta}{beta} of {sup 48}Ca. We have been working on CANDLES detector system to sense much longer lifetime region. We have developed techniques to reduce backgrounds. The CADLES detector system was installed at Kamioka underground laboratory. Here I describe a schematic view of the system.

Kishimoto, T.; Nomachi, M. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka Japan (Japan); Research Center for Nuclear Physics, Osaka University, 10-1 Mihogaoka Ibaraki Osaka Japan (Japan); Yoshida, S.; Matsuoka, K.; Ichimura, K.; Ito, G.; Yasuda, K.; Kakubata, H.; Miyashita, M.; Takubo, K.; Saka, M.; Seki, K. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka Japan (Japan); Ajimura, S.; Umehara, S.; Nakatani, N. [Research Center for Nuclear Physics, Osaka University, 10-1 Mihogaoka Ibaraki Osaka Japan (Japan); Tamagawa, Y.; Ogawa, I. [Graduate School of Engineering, University of Fukui,Fukui (Japan); Fushimi, K. [Faculty of Integrated Arts and Science, Tokushima University, Tokushima (Japan); Hazama, R. [Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima (Japan); Ohsumi, H. [Faculty of Culture and Education, Saga University, Saga (Japan)

2011-10-21T23:59:59.000Z

24

Disentangling the various Mechanisms of neutrinoless double beta decay to extract the neutrino mass  

Science Conference Proceedings (OSTI)

It is well known that there exist many mechanisms that may contribute to neutrinoless double beta decay. By exploiting the fact that the associated nuclear matrix elements are target dependent we show that, given definite experimental results on a sufficient number of targets, one can determine or sufficiently constrain all lepton violating parameters including the mass term. As a specific example we show that, given the observation of the 0{nu}{beta}{beta}-decay in three different nuclei, e.g. {sup 76}Ge, {sup 100}Mo and {sup 130}Te, and assuming just three active lepton number violating parameters, e.g. light and heavy neutrino mass mechanisms in left handed currents as well as R-parity breaking SUSY mechanism, one may determine all lepton violating parameters, provided that they are relatively real.

Vergados, J. D. [Physics Department, University of Ioannina, Ioannina, GR 451 10, Greece and Theory Division, CERN 1211, Geneva 23 (Greece)

2011-12-16T23:59:59.000Z

25

Combining and comparing neutrinoless double beta decay experiments using different nuclei  

E-Print Network (OSTI)

We perform a global fit of the most relevant neutrinoless double beta decay experiments within the standard model with massive Majorana neutrinos. Using Bayesian inference makes it possible to take into account the theoretical uncertainties on the nuclear matrix elements in a fully consistent way. First, we analyze the data used to claim the observation of neutrinoless double beta decay in Ge-76, and find strong evidence (according to Jeffrey's scale) for a peak in the spectrum and moderate evidence for that the peak is actually close to the energy expected for the neutrinoless decay. We also find a significantly larger statistical error than the original analysis, which we include in the comparison with other data. Then, we statistically test the consistency between this claim with that of recent measurements using Xe-136. We find that the two data sets are about 40 to 80 times more probable under the assumption that they are inconsistent, depending on the nuclear matrix element uncertainties and the prior on the smallest neutrino mass. Hence, there is moderate to strong evidence of incompatibility, and for equal prior probabilities the posterior probability of compatibility is between 1.3% and 2.5%. If one, despite such evidence for incompatibility, combines the two data sets, we find that the total evidence of neutrinoless double beta decay is negligible. If one ignores the claim, there is weak evidence against the existence of the decay. We also perform approximate frequentist tests of compatibility for fixed ratios of the nuclear matrix elements, as well as of the no signal hypothesis. Generalization to other sets of experiments as well as other mechanisms mediating the decay is possible.

Johannes Bergstrom

2012-12-18T23:59:59.000Z

26

First search for double-beta decay of 184Os and 192Os  

E-Print Network (OSTI)

A search for double-beta decay of osmium has been realized for the first time with the help of an ultra-low background HPGe gamma detector at the underground Gran Sasso National Laboratories of the INFN (Italy). After 2741 h of data taking with a 173 g ultra-pure osmium sample limits on double-beta processes in 184Os have been established at the level of T_{1/2} about 10^{14}-10^{17} yr. Possible resonant double-electron captures in 184Os were searched for with a sensitivity T_{1/2} about 10^{16} yr. A half-life limit T_{1/2} > 5.3 10^{19} yr was set for the double-beta decay of 192Os to the first excited level of 192Pt. The radiopurity of the osmium sample has been investigated and radionuclides 137Cs, 185Os and 207Bi were detected in the sample, while activities of 40K, 60Co, 226Ra and 232Th were limited at the mBq/kg level.

P. Belli; R. Bernabei; F. Cappella; R. Cerulli; F. A. Danevich; S. d'Angelo; A. Di Marco; A. Incicchitti; G. P. Kovtun; N. G. Kovtun; M. Laubenstein; D. V. Poda; O. G. Polischuk; A. P. Shcherban; V. I. Tretyak

2013-01-15T23:59:59.000Z

27

An experimental investigation of double beta decay of /sup 100/Mo  

SciTech Connect

New limits on half-lives for several double beta decay modes of /sup 100/Mo were obtained with a novel experimental system which included thin source films interleaved with a coaxial array of windowless silicon detectors. Segmentation and timing information allowed backgrounds originating in the films to be studied in some detail. Dummy films containing /sup 96/Mo were used to assess remaining backgrounds. With 0.1 mole years of /sup 100/Mo data collected, the lower half-life limits at 90% confidence were 2.7 /times/ 10/sup 18/ years for decay via the two-neutrino mode, 5.2 /times/10/sup 19/ years for decay with the emission of a Majoron, and 1.6 /times/ 10/sup 20/ years and 2.2 /times/ 10/sup 21/ years for neutrinoless 0/sup +/ ..-->.. 2/sup +/ and 0/sup +/ ..-->.. 0/sup +/ transitions, respectively. 50 refs., 38 figs., 11 tabs.

Dougherty, B.L.

1988-11-17T23:59:59.000Z

28

Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism.  

E-Print Network (OSTI)

ar X iv :0 90 2. 46 97 v1 [ he p- ph ] 26 Fe b 2 00 9 CAVENDISH-HEP-2009-03, DAMTP-2009-15, DO-TH-09/01 Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism B. C. Allanach? DAMTP, University of Cambridge... how data from the Large Hadron Collider (LHC) can favor or disfavor the latter possibility. The experimental observations of neutrino oscillations has lead to the realization that at least two of the three known neutrinos have masses [5]. Thus...

Allanach, B C; Kom, C H; Pas, H

29

Ba-ion extraction from a high pressure Xe gas for double-beta decay studies with EXO  

E-Print Network (OSTI)

An experimental setup is being developed to extract Ba ions from a high-pressure Xe gas environment. It aims to transport Ba ions from 10 bar Xe to vacuum conditions. The setup utilizes a converging-diverging nozzle in combination with a radio-frequency (RF) funnel to move Ba ions into vacuum through the pressure drop of several orders of magnitude. This technique is intended to be used in a future multi-ton detector investigating double-beta decay in $^{136}$Xe. Efficient extraction and detection of Ba ions, the decay product of Xe, would allow for a background-free measurement of the $^{136}$Xe double-beta decay.

T. Brunner; D. Fudenberg; A. Sabourov; V. L. Varentsov; G. Gratta; D. Sinclair; for the EXO collaboration

2013-02-27T23:59:59.000Z

30

Solar neutrino-electron scattering as background limitation for double beta decay  

E-Print Network (OSTI)

The background on double beta decay searches due to elastic electron scattering of solar neutrinos of all double beta emitters with Q-value larger than 2 MeV is calculated, taking into account survival probability and flux uncertainties of solar neutrinos. This work determines the background level to be [1-2]E-7 counts /keV/kg/yr, depending on the precise Q-value of the double beta emitter. It is also shown that the background level increases dramatically if going to lower Q-values. Furthermore, studies are done for various detector systems under consideration for next generation experiments. It was found that experiments based on loaded liquid scintillator have to expect a higher background. Within the given nuclear matrix element uncertainties any approach exploring the normal hierarchy has to face this irreducible background, which is a limitation on the minimal achievable background for purely calorimetric approaches. Large scale liquid scintillator experiments might encounter this problem already while exploring the inverted hierarchy. Potential caveats by using more sophisticated experimental setups are also discussed.

N. F. de Barros; K. Zuber

2011-03-29T23:59:59.000Z

31

Measurement of the Double-Beta Decay Half-life of {sup 136}Xe in KamLAND-Zen  

Science Conference Proceedings (OSTI)

We present results from the KamLAND-Zen double-beta decay experiment based on an exposure of 77.6 days with 129 kg of {sup 136}Xe. The measured two-neutrino double-beta decay half-life of {sup 136}Xe is T{sup 2{nu}}{sub 1/2} = 2:38 {+-}#6; 0:02(stat)#6;{+-}0.14(syst)#2;x10{sup 21} yr, consistent with a recent measurement by EXO-200. We also obtain a lower limit for the neutrinoless double-beta decay half-life, T{sup 0{nu}}{sub 1/2} > 5.7 x#2; 10{sup 24} yr at 90% C.L.

KamLAND-Zen Collaboration; Gando, A.; Gando, Y.; Hanakago, H.; Ikeda, H.; Inoue, K.; Kato, R.; Koga, M.; Matsuda, S.; Mitsui, T.; Nakada, T.; Nakamura, K.; Obata, A.; Oki, A.; Ono, Y.; Shimizu, I.; Shirai, J.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B. D.; Yamada, S.; Yoshida, H.; Kozlov, A.; Yoshida, S.; Banks, T. I.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; O'Donnell, T.; Berger, B. E.; Efremenko, Y.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Enomoto, S.; Decowski, M. P.

2012-01-23T23:59:59.000Z

32

Search for double beta decay with HPGe detectors at the Gran Sasso underground laboratory  

E-Print Network (OSTI)

Neutrinoless double-beta decay is practically the only way to establish the Majorana nature of the neutrino mass and its decay rate provides a probe of an effective neutrino mass. Double beta experiments are long-running underground experiments with specific challenges concerning the background reduction and the long term stability. These problems are addressed in this work for the Heidelberg-Moscow (HdM), GENIUS Test Facility (TF) and GERDA experiments. The HdM experiment collected data with enriched 76Ge high purity (HPGe) detectors from 1990 to 2003. An improved analysis of HdM data is presented, exploiting new calibration and spectral shape measurements with the HdM detectors. GENIUS-TF was a test-facility that verified the feasibility of using bare germanium detectors in liquid nitrogen. The first year results of this experiment are discussed. The GERDA experiment has been designed to further increase the sensitivity by operating bare germanium detectors in a high purity cryogenic liquid, which simultaneously serves as a shielding against background and as a cooling media. In the preparatory stage of GERDA, an external background gamma flux measurement was done at the experimental site in the Hall A of the Gran Sasso laboratory. The characterization of the enriched detectors from the HdM and IGEX experiments was performed in the underground detector laboratory for the GERDA collaboration. Long term stability measurements of a bare HPGe detector in liquid argon were carried out. Based on these measurements, the first lower limit on the half-life of neutrinoless double electron capture of 36Ar was established to be 1.85*10^18 years at 68% C.L.

Oleg Chkvorets

2008-12-05T23:59:59.000Z

33

The SNO Solar Neutrino Data, Neutrinoless Double Beta-Decay and Neutrino Mass Spectrum  

E-Print Network (OSTI)

Assuming 3 neutrino mixing and massive Majorana neutrinos, we analyze the implications of the results of the solar neutrino experiments, including the latest SNO data, which favor the LMA MSW solution of the solar neutrino problem with \\tan^2 \\theta_sol | in neutrinoless double beta decay. For \\cos (2 \\theta_sol) \\geq 0.26, which follows from the analysis of the new solar neutrino data, we find significant lower limits on || in the cases of quasi-degenerate and inverted hierarchy neutrino mass spectrum, || \\geq 0.035 eV and || \\geq 8.5 10^-3 eV, respectively. If the spectrum is hierarchical the upper limit holds || \\leq 8.2 10^-3 eV. Correspondingly, not only a measured value of || \

S. Pascoli; S. T. Petcov

2002-05-02T23:59:59.000Z

34

Depth Requirements for a Tonne-scale 76Ge Neutrinoless Double-beta Decay Experiment  

E-Print Network (OSTI)

Neutrinoless double-beta decay experiments can potentially determine the Majorana or Dirac nature of the neutrino, and aid in understanding the neutrino absolute mass scale and hierarchy. Future 76Ge-based searches target a half-life sensitivity of >10^27 y to explore the inverted neutrino mass hierarchy. Reaching this sensitivity will require a background rate of required to reach this background goal in a tonne-scale experiment with a compact (copper and lead) shield based on Monte Carlo calculations of cosmic-ray background rates. We find that, in light of the presently large uncertainties in these types of calculations, a site with an underground depth >~5200 mwe is required for a tonne-scale experiment with a compact shield similar to the planned 40-kg MAJORANA DEMONSTRATOR. The required overburden is highly dependent on the chosen shielding configuration and could be relaxed significantly if, for example, a liquid cryogen and water shield, or an active neutron shield were employed. Operation of the MAJORANA DEMONSTRATOR and GERDA detectors will serve to reduce the uncertainties on cosmic-ray background rates and will impact the choice of shielding style and location for a future tonne-scale experiment. 4/2013: The peer review process revealed that one of the veto rejection factors (the factor-of-4 described on p12) needs to be better established. Our reevaluation of this parameter to date has not yielded strong support for the value stated in the manuscript, and we require further study to develop a solid estimate. This further study will supersede the work described in this manuscript, and may or may not lead to the same conclusion regarding the ~>5200 mwe requirement for future tonne-scale 76Ge neutrinoless double beta decay experiments.

The MAJORANA Collaboration; E. Aguayo; F. T. Avignone III; H. O. Back; A. S. Barabash; M. Bergevin; F. E. Bertrand; M. Boswell; V. Brudanin; M. Busch; Y-D. Chan; C. D. Christofferson; J. I. Collar; D. C. Combs; R. J. Cooper; J. A. Detwiler; P. J. Doe; Yu. Efremenko; V. Egorov; H. Ejiri; S. R. Elliott; J. Esterline; J. E. Fast; N. Fields; P. Finnerty; F. M. Fraenkle; V. M. Gehman; G. K. Giovanetti; M. P. Green; V. E. Guiseppe; K. Gusey; A. L. Hallin; R. Hazama; R. Henning; A. Hime; E. W. Hoppe; M. Horton; S. Howard; M. A. Howe; R. A. Johnson; K. J. Keeter; M. E. Keillor; C. Keller; J. D. Kephart; M. F. Kidd; A. Knecht; O. Kochetov; S. I. Konovalov; R. T. Kouzes; B. D. LaFerriere; B. H. LaRoque; J. Leon; L. E. Leviner; J. C. Loach; S. MacMullin; M. G. Marino; R. D. Martin; D. -M. Mei; J. H. Merriman; M. L. Miller; L. Mizouni; M. Nomachi; J. L. Orrell; N. R. Overman; D. G. Phillips II; A. W. P. Poon; G. Perumpilly; G. Prior; D. C. Radford; K. Rielage; R. G. H. Robertson; M. C. Ronquest; A. G. Schubert; T. Shima; M. Shirchenko; K. J. Snavely; V. Sobolev; D. Steele; J. Strain; K. Thomas; V. Timkin; W. Tornow; I. Vanyushin; R. L. Varner; K. Vetter; K. Vorren; J. F. Wilkerson; B. A. Wolfe; E. Yakushev; A. R. Young; C. -H. Yu; V. Yumatov; C. Zhang

2011-09-19T23:59:59.000Z

35

A measurement of the 2 neutrino double beta decay rate of Te-130 in the CUORICINO experiment  

Science Conference Proceedings (OSTI)

CUORICINO was a cryogenic bolometer experiment designed to search for neutrinoless double beta decay and other rare processes, including double beta decay with two neutrinos (2{nu}{beta}{beta}). The experiment was located at Laboratori Nazionali del Gran Sasso and ran for a period of about 5 years, from 2003 to 2008. The detector consisted of an array of 62 TeO{sub 2} crystals arranged in a tower and operated at a temperature of #24;10 mK. Events depositing energy in the detectors, such as radioactive decays or impinging particles, produced thermal pulses in the crystals which were read out using sensitive thermistors. The experiment included 4 enriched crystals, 2 enriched with {sup 130}Te and 2 with {sup 128}Te, in order to aid in the measurement of the 2{nu}{beta}{beta} rate. The enriched crystals contained a total of #24;350 g {sup 130}Te. The 128-enriched (130-depleted) crystals were used as background monitors, so that the shared backgrounds could be subtracted from the energy spectrum of the 130- enriched crystals. Residual backgrounds in the subtracted spectrum were fit using spectra generated by Monte-Carlo simulations of natural radioactive contaminants located in and on the crystals. The 2{nu}{beta}{beta} half-life was measured to be T{sup 2{nu}}{sub 1/2} = [9.81{+-} #6;0.96(stat){+-} 0.49(syst)]#2;x10{sup 20} y.

Kogler, Laura

2011-11-03T23:59:59.000Z

36

Observation of Two-Neutrino Double-Beta Decay in [superscript 136]Xe with the EXO-200 Detector  

E-Print Network (OSTI)

We report the observation of two-neutrino double-beta decay in [superscript 136]Xe with T[subscript 1/2]=2.11±0.04(stat)±0.21(syst)×10[superscript 21]??yr. This second-order process, predicted by the standard model, has ...

Waldman, Samuel J.

37

MOON for a next-generation neutrino-less double-beta decay experiment: Present status and perspective  

SciTech Connect

The performance of the MOON detector for a next-generation neutrino-less double-beta decay experiment was evaluated by means of the Monte Carlo method. The MOON detector was found to be a feasible solution for the future experiment to search for the Majorana neutrino mass in the range of 100-30 meV.

Shima, T.; /Osaka U., Res. Ctr. Nucl. Phys.; Doe, P.J.; /Washington U., Seattle; Ejiri, H.; /Osaka U., Res. Ctr. Nucl. Phys. /NIRS, Chiba /Prague, Tech. U.; Elliot, S.R.; /Washington U., Seattle /Los Alamos; Engel, J.; /North Carolina U.; Finger, M.; /Charles U.; Finger, M.; /Charles U.; Fushimi, K.; /Tokushima U.; Gehman, V.M.; /Washington U., Seattle /Los Alamos; Greenfield, M.B.; /Tokyo, Intl. Christian U.; Hazama, R.; /Hiroshima U. /NIRS, Chiba

2008-01-01T23:59:59.000Z

38

Glossary Term - Beta Decay  

NLE Websites -- All DOE Office Websites (Extended Search)

Avogadro's Number Avogadro's Number Previous Term (Avogadro's Number) Glossary Main Index Next Term (Beta Particle) Beta Particle Beta Decay Beta decay results in the emission of an electron and antineutrino, or a positron and neutrino. Beta decay is one process that unstable atoms can use to become more stable. There are two types of beta decay, beta-minus and beta-plus. During beta-minus decay, a neutron in an atom's nucleus turns into a proton, an electron and an antineutrino. The electron and antineutrino fly away from the nucleus, which now has one more proton than it started with. Since an atom gains a proton during beta-minus decay, it changes from one element to another. For example, after undergoing beta-minus decay, an atom of carbon (with 6 protons) becomes an atom of nitrogen (with 7 protons).

39

White Paper on the Majorana Zero-Neutrino Double-Beta Decay Experiment  

E-Print Network (OSTI)

The objective of the Majorana Experiment is to study neutrinoless double beta decay (0nbb) with an effective Majorana-neutrino mass sensitivity below 50 meV in order to characterize the Majorana nature of the neutrino, the Majorana mass spectrum, and the absolute mass scale. An experimental study of the neutrino mass scale implied by neutrino oscillation results is now technically within our grasp. This exciting physics goal is best pursued using the well-established technique of searching for 0nbb of 76Ge, augmented with recent advances in signal processing and detector design. The Majorana Experiment will consist of a large mass of 76Ge in the form of high-resolution intrinsic germanium detectors located deep underground within a low-background shielding environment. Observation of a sharp peak at the bb endpoint will quantify the 0nbb half-life and thus the effective Majorana mass of the electron neutrino. In addition to the modest R&D program, we present here an overview of the entire project in order to help put in perspective the scope, the low level of technical risk, and the readiness of the Collaboration to immediately begin the undertaking.

The Majorana collaboration

2003-11-13T23:59:59.000Z

40

Addendum: The SNO Solar Neutrino Data, Neutrinoless Double Beta-Decay and Neutrino Mass Spectrum  

E-Print Network (OSTI)

We update our earlier study in [1], which was inspired by the 2002 SNO data, on the implications of the results of the solar neutrino experiments for the predictions of the effective Majorana mass in neutrinoless double beta-decay, ||. We obtain predictions for || using the values of the neutrino oscillation parameters, obtained in the analyzes of the presently available solar neutrino data, including the just published data from the salt phase of the SNO experiment, the atmospheric neutrino and CHOOZ data and the first data from the KamLAND experiment. The main conclusion reached in ref. [1] of the existence of significant lower bounds on || in the cases of neutrino mass spectrum of inverted hierarchical (IH) and quasi-degenerate (QD) type is strongly reinforced by fact that combined solar neutrino data i) exclude the possibility of cos(2 \\theta_\\odot)=0 at more than 5 s.d., ii) determine as a best fit value cos(2 \\theta_\\odot)=0.40, and ii) imply at 95% C.L. that cos(2 \\theta_\\odot) \\geq 0.22, \\theta_\\odot being the solar neutrino mixing angle. For the IH and QD spectra we get using, e.g., the 90% C.L. allowed ranges of values of the oscillation parameters, || \\geq 0.010 eV and || \\geq 0.043 eV, respectively. We also comment on the possibility to get information on the neutrino mass spectrum and on the CP-violation in the lepton sector due to Majorana CP-violating phases.

S. Pascoli; S. T. Petcov

2003-09-30T23:59:59.000Z

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41

Double-{beta}-decay Q values of {sup 130}Te, {sup 128}Te, and {sup 120}Te  

SciTech Connect

The double-{beta}-decay Q values of {sup 130}Te, {sup 128}Te, and {sup 120}Te have been determined from parent-daughter mass differences measured with the Canadian Penning Trap mass spectrometer. The {sup 132}Xe-{sup 129}Xe mass difference, which is precisely known, was also determined to confirm the accuracy of these results. The {sup 130}Te Q value was found to be 2527.01{+-}0.32 keV, which is 3.3 keV lower than the 2003 Atomic Mass Evaluation recommended value and is consistent with another recent Penning trap measurement. The {sup 128}Te and {sup 120}Te Q values were found to be 865.87{+-}1.31 and 1714.81{+-}1.25 keV, respectively. For {sup 120}Te, this reduction in uncertainty of nearly a factor of 8 opens up the possibility of using this isotope for sensitive searches for neutrinoless double-electron capture and electron capture with {beta}{sup +}emission.

Scielzo, N. D. [Physical Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Caldwell, S.; Savard, G.; Sternberg, M.; Van Schelt, J. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics, University of Chicago, Chicago, Illinois 60637 (United States); Clark, J. A.; Levand, A. F.; Sun, T. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Deibel, C. M. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Joint Institute of Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48824 (United States); Fallis, J. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Gulick, S. [Department of Physics, McGill University, Montreal, Quebec H3A 2T8 (Canada); Lascar, D. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208 (United States); Li, G. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics, McGill University, Montreal, Quebec H3A 2T8 (Canada); Mintz, J. [Department of Nuclear Engineering, University of California, Berkeley, California 94720 (United States); Norman, E. B. [Physical Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Department of Nuclear Engineering, University of California, Berkeley, California 94720 (United States); Sharma, K. S. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)

2009-08-15T23:59:59.000Z

42

The MAJORANA DEMONSTRATOR: An R&D project towards a tonne-scale germanium neutrinoless double-beta decay search  

E-Print Network (OSTI)

The MAJORANA collaboration is pursuing the development of the so-called MAJORANA DEMONSTRATOR. The DEMONSTRATOR is intended to perform research and development towards a tonne-scale germanium-based experiment to search for the neutrinoless double-beta decay of Ge-76. The DEMONSTRATOR can also perform a competitive direct dark matter search for light WIMPs in the 1-10 GeV/c^2 mass range. It will consist of approximately 60-kg of germanium detectors in an ultra-low background shield located deep underground at the Sanford Underground Laboratory in Lead, SD. The DEMONSTRATOR will also perform background and technology studies, and half of the detector mass will be enriched germanium. This talk will review the motivation, design, technology and status of the DEMONSTRATOR.

Reyco Henning; for the MAJORANA Collaboration

2009-07-09T23:59:59.000Z

43

Performance of a large TeO2 crystal as a cryogenic bolometer in searching for neutrinoless double beta decay  

E-Print Network (OSTI)

Bolometers are ideal devices in the search for neutrinoless Double Beta Decay. Enlarging the mass of individual detectors would simplify the construction of a large experiment, but would also decrease the background per unit mass induced by alpha-emitters located close to the surfaces and background arising from external and internal gamma's. We present the very promising results obtained with a 2.13 kg TeO2 crystal. This bolometer, cooled down to a temperature of 10.5 mK in a dilution refrigerator located deep underground in the Gran Sasso National Laboratories, represents the largest thermal detector ever operated. The detector exhibited an energy resolution spanning a range from 3.9 keV (at 145 keV) to 7.8 keV (at the 2615 gamma-line of 208Tl) FWHM. We discuss the decrease in the background per unit mass that can be achieved increasing the mass of a bolometer.

L. Cardani; L. Gironi; J. W. Beeman; I. Dafinei; Z. Ge; G. Pessina; S. Pirro; Y. Zhu

2011-06-03T23:59:59.000Z

44

Q value for the double-{beta} decay of {sup 136}Xe  

Science Conference Proceedings (OSTI)

The high-resolution, deflection-type mass spectrometer, Manitoba II, has been used to determine directly the mass difference {sup 136}Xe-{sup 136}Ba to be 2639.6 (0.6) {mu}u, giving Q{sub {beta}{beta}}=2458.7 (0.6) keV.

McCowan, P. M.; Barber, R. C. [Department of Physics and Astronomy, University of Manitoba, Winnipeg MB R3T 2N2 (Canada)

2010-08-15T23:59:59.000Z

45

Discovery potential of xenon-based neutrinoless double beta decay experiments in light of small angular scale CMB observations  

E-Print Network (OSTI)

The South Pole Telescope (SPT) has probed an expanded angular range of the CMB temperature power spectrum. Their recent analysis of the latest cosmological data prefers nonzero neutrino masses, mnu = 0.32+-0.11 eV. This result, if confirmed by the upcoming Planck data, has deep implications on the discovery of the nature of neutrinos. In particular, the values of the effective neutrino mass involved in neutrinoless double beta decay (bb0nu) are severely constrained for both the direct and inverse hierarchy, making a discovery much more likely. In this paper, we focus in xenon-based bb0nu experiments, on the double grounds of their good performance and the suitability of the technology to large-mass scaling. We show that the current generation, with effective masses in the range of 100 kg and conceivable exposures in the range of 500 kg year, could already have a sizable opportunity to observe bb0nu events, and their combined discovery potential is quite large. The next generation, with an exposure in the range of 10 ton year, would have a much more enhanced sensitivity, in particular due to the very low specific background that all the xenon technologies (liquid xenon, high-pressure xenon and xenon dissolved in liquid scintillator) can achieve. In addition, a high-pressure xenon gas TPC also features superb energy resolution. We show that such detector can fully explore the range of allowed effective Majorana masses, thus making a discovery very likely.

J. J. Gomez-Cadenas; J. Martin-Albo; J. Muñoz Vidal; C. Peña-Garay

2013-01-14T23:59:59.000Z

46

The MAJORANA DEMONSTRATOR: Progress towards showing the feasibility of a tonne-scale 76Ge neutrinoless double-beta decay experiment  

E-Print Network (OSTI)

The MAJORANA DEMONSTRATOR will search for the neutrinoless double-beta decay of the 76Ge isotope with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate the neutrino is its own anti-particle, demonstrate that lepton number is not conserved, and provide information on the absolute mass-scale of the neutrino. The DEMONSTRATOR is being assembled at the 4850 foot level of the Sanford Underground Research Facility in Lead, South Dakota. The array will be contained in a low-background environment and surrounded by passive and active shielding. The goals for the DEMONSTRATOR are: demonstrating a background rate less than 3 t$^{-1}$ y$^{-1}$ in the 4 keV region of interest (ROI) surrounding the 2039 keV 76Ge endpoint energy; establishing the technology required to build a tonne-scale germanium based double-beta decay experiment; testing the recent claim of observation of neutrinoless double-beta decay [H. V. Klapdor-Kleingrothaus and I. V. Krivosheina, Mod. Phys. Lett. A21, 1547 (2006)]; and performing a direct search for light WIMPs (3-10 GeV).

P. Finnerty; E. Aguayo; M. Amman; F. T. Avignone. III; A. S. Barabash; P. J. Barton; J. R. Beene; F. E. Bertrand; M. Boswell; V. Brudanin; M. Busch; Y. -D. Chan; C. D. Christofferson; J. I. Collar; D. C. Combs; R. J. Cooper; J. A. Detwiler; P. J. Doe; Yu. Efremenko; V. Egorov; H. Ejiri; S. R. Elliott; J. Esterline; J. E. Fast; N. Fields; F. M. Fraenkle; A. Galindo-Uribarri; V. M. Gehman; G. K. Giovanetti; M. P. Green; V. E. Guiseppe; K. Gusey; A. L. Hallin; R. Hazama; R. Henning; E. W. Hoppe; M. Horton; S. Howard; M. A. Howe; R. A. Johnson; K. J. Keeter; M. F. Kidd; A. Knecht; O. Kochetov; S. I. Konovalov; R. T. Kouzes; B. D. LaFerriere; J. Leon; L. E. Leviner; J. C. Loach; P. N. Luke; S. MacMullin; M. G. Marino; R. D. Martin; J. H. Merriman; M. L. Miller; L. Mizouni; M. Nomachi; J. L. Orrell; N. R. Overman; G. Perumpilly; D. G. Phillips. II; A. W. P. Poon; D. C. Radford; K. Rielage; R. G. H. Robertson; M. C. Ronquest; A. G. Schubert; T. Shima; M. Shirchenko; K. J. Snavely; D. Steele; J. Strain; V. Timkin; W. Tornow; R. L. Varner; K. Vetter; K. Vorren; J. F. Wilkerson; E. Yakushev; H. Yaver; A. R. Young; C-H. Yu. and. V. Yumatov.

2012-10-09T23:59:59.000Z

47

Characterization of a broad energy germanium detector and application to neutrinoless double beta decay search in Ge-76  

E-Print Network (OSTI)

The performance of a 630g commercial broad energy germanium (BEGe) detector has been systematically investigated. Energy resolution, linearity, stability vs. high-voltage (HV) bias, thickness and uniformity of dead layers have been measured and found to be excellent. Special attention has been dedicated to the study of the detector response as a function of bias HV. The nominal depletion voltage being 3000V, the detector under investigation shows a peculiar behavior for biases around 2000V: in a narrow range of about 100V the charge collection is strongly reduced. The detector seems to be composed by two parts: a small volume around the HV contact where charges are efficiently collected as at higher voltage, and a large volume where charges are poorly collected. A qualitative explanation of this behavior is presented. An event-by-event pulse shape analysis based on A/E (maximum amplitude of the current pulse over the total energy released in the detector) has been applied to events in different energy regions and found very effective in rejecting non localized events. In conclusion, BEGe detectors are excellent candidates for the second phase of GERDA, an experiment devoted to neutrinoless double beta decay of Ge-76.

M. Agostini; E. Bellotti; R. Brugnera; C. M. Cattadori; A. D'Andragora; A. di Vacri; A. Garfagnini; M. Laubenstein; L. Pandola; C. A. Ur

2010-12-23T23:59:59.000Z

48

Fundamental processes in the interacting boson model: 0{nu}{beta}{beta} decay  

Science Conference Proceedings (OSTI)

A program to calculate nuclear matrix elements for fundamental processes in the interacting boson model has been initiated. Results for the nuclear matrix elements in neutrinoless double beta decay 0{nu}{beta}{beta} are presented.

Iachello, F. [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520-8120 (United States); Barea, J. [Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile)

2011-05-06T23:59:59.000Z

49

Beta-decay beyond the standard model  

Science Conference Proceedings (OSTI)

We discuss possible sources of new interactions in beta-decay and the role of beta-decay experiments in obtaining information on them. 46 refs.

Herczeg, P.

1989-01-01T23:59:59.000Z

50

WLS R\\&D for the Detection of Noble Gas Scintillation at LBL: seeing the light from neutrinos, to dark matter, to double beta decay  

E-Print Network (OSTI)

Radiation detectors with noble gasses as the active medium are becoming increasingly common in experimental programs searching for physics beyond the standard model. Nearly all of these experiments rely to some degree on collecting scintillation light from noble gasses. The VUV wavelengths associated with noble gas scintillation mean that most of these experiments use a fluorescent material to shift the direct scintillation light into the visible or near UV band. We present an overview of the R&D program at LBL related to noble gas detectors for neutrino physics, double beta decay, and dark matter. This program ranges from precise measurements of the fluorescence behavior of wavelength shifting films, to the prototyping of large are VUV sensitive light guides for multi-kiloton detectors.

V. M. Gehman

2013-08-12T23:59:59.000Z

51

Test of the unactivated calcium fluoride crystal for use as a scintillation detector in Ca/sup 48/ double beta decay experiment  

SciTech Connect

The test results of the properties of the unactivated CaF/sub 2/ scintillation crystal detector is reported. The energy response of a small size CaF/sub 2/ crystal and a large CaF/sub 2/ crystal detector, which will be used in the Ca/sup 48/ Double Beta Decay (DBD) experiment, to gamma rays and an electron beam from 6 to 10 MeV was tested. The results indicate that the linear energy response range can be extended to 10 MeV for the large CaF/sub 2/ detector. Meanwhile, the relation of the energy resolution to the incident particle energy is represented by E/sup -1/2/ (MeV). (It is anticipated that the energy resolution at 4.27 MeV will be about 9%.)

Weihua, T.; Ke, Y.; Yucan, Z.; Wenheng, Z.; Zhipeng, Z.; Junguang, L.; Hansheng, S.; Minghan, Y.; Yanfeng, F.; Shaoxin, O.

1989-01-01T23:59:59.000Z

52

Neutron Beta Decay Studies with Nab  

E-Print Network (OSTI)

Precision measurements in neutron beta decay serve to determine the coupling constants of beta decay and allow for several stringent tests of the standard model. This paper discusses the design and the expected performance of the Nab spectrometer.

Baeßler, S; Alonzi, L P; Balascuta, S; Barrón-Palos, L; Bowman, J D; Bychkov, M A; Byrne, J; Calarco, J R; Chupp, T; Vianciolo, T V; Crawford, C; Frlež, E; Gericke, M T; Glück, F; Greene, G L; Grzywacz, R K; Gudkov, V; Harrison, D; Hersman, F W; Ito, T; Makela, M; Martin, J; McGaughey, P L; McGovern, S; Page, S; Penttilä, S I; Po?ani?, D; Rykaczewski, K P; Salas-Bacci, A; Tompkins, Z; Wagner, D; Wilburn, W S; Young, A R

2012-01-01T23:59:59.000Z

53

Neutron Beta Decay Studies with Nab  

E-Print Network (OSTI)

Precision measurements in neutron beta decay serve to determine the coupling constants of beta decay and allow for several stringent tests of the standard model. This paper discusses the design and the expected performance of the Nab spectrometer.

S. Baeßler; R. Alarcon; L. P. Alonzi; S. Balascuta; L. Barrón-Palos; J. D. Bowman; M. A. Bychkov; J. Byrne; J. R. Calarco; T. Chupp; T. V. Vianciolo; C. Crawford; E. Frlež; M. T. Gericke; F. Glück; G. L. Greene; R. K. Grzywacz; V. Gudkov; D. Harrison; F. W. Hersman; T. Ito; M. Makela; J. Martin; P. L. McGaughey; S. McGovern; S. Page; S. I. Penttilä; D. Po?ani?; K. P. Rykaczewski; A. Salas-Bacci; Z. Tompkins; D. Wagner; W. S. Wilburn; A. R. Young

2012-09-20T23:59:59.000Z

54

(beta beta)_{0 nu}-decay: a possible test of the nuclear matrix element calculations  

E-Print Network (OSTI)

The existing calculations of the nuclear matrix elements of the neutrinoless double beta-decay differ by about a factor three. This uncertainty prevents quantative interpretation of the results of experiments searching for this process. We suggest here that the observation of the neutrinoless double beta-decay of several nuclei in future experiments of could allow to test different calculations of the nuclear matrix elements through the direct comparison of them with the experimental data.

S. M. Bilenky; J. A. Grifols

2002-07-23T23:59:59.000Z

55

Nuclear beta-decay measurements and |Vud|  

E-Print Network (OSTI)

Some recent work in nuclear beta decay related to the value of |Vud| is described along with some near-term goals for future measurements.

Dan Melconian

2011-08-11T23:59:59.000Z

56

Nuclear beta-decay measurements and |Vud|  

E-Print Network (OSTI)

Some recent work in nuclear beta decay related to the value of |Vud| is described along with some near-term goals for future measurements.

Melconian, Dan

2011-01-01T23:59:59.000Z

57

Beta decays with momentum space Majorana spinors  

E-Print Network (OSTI)

We construct and apply to beta decays a truly neutral local quantum field that is entirely based upon momentum space Majorana spinors. We make the observation that theory with momentum space Majorana spinors of real C parities is equivalent to Dirac's theory. For imaginary C parities, the neutrino mass can drop from the single beta decay trace and reappear in 0\

M. Kirchbach; C. Compean; L. Noriega

2004-11-24T23:59:59.000Z

58

Search for double beta decay of Zinc and Tungsten with the help of low-background ZnWO4 crystal scintillators  

E-Print Network (OSTI)

Double beta processes in 64-Zn, 70-Zn, 180-W, and 186-W have been searched for with the help of large volume (0.1-0.7 kg) low background ZnWO4 crystal scintillators at the Gran Sasso National Laboratories of the INFN. Total time of measurements exceeds 10 thousands hours. New improved half-life limits on double electron capture and electron capture with positron emission in 64-Zn have been set, in particular (all the limits are at 90% C.L.): T1/2(0nu2EC)> 1.1e20 yr, T1/2(2nuECbeta+)>7.0e20 yr, and T1/2(0nuECbeta+)>4.3e20 yr. The different modes of double beta processes in 70-Zn, 180-W, and 186-W have been restricted at the level of 1e17-1e20 yr.

P. Belli; R. Bernabei; F. Cappella; R. Cerulli; F. A. Danevich; B. V. Grinyov; A. Incicchitti; V. V. Kobychev; V. M. Mokina; S. S. Nagorny; L. L. Nagornaya; S. Nisi; F. Nozzoli; D. V. Poda; D. Prosperi; V. I. Tretyak; S. S. Yurchenko

2008-11-14T23:59:59.000Z

59

Results from a search for the 0 {nu}{beta}{beta}-decay of {sup 130}Te  

SciTech Connect

A detailed description of the CUORICINO {sup 130}Te neutrinoless double-beta (0 {nu}{beta}{beta}) decay experiment is given and recent results are reported. CUORICINO is an array of 62 tellurium oxide (TeO{sub 2}) bolometers with an active mass of 40.7 kg. It is cooled to {approx}8-10 mK by a dilution refrigerator shielded from environmental radioactivity and energetic neutrons. It is running in the Laboratori Nazionali del Gran Sasso (LNGS) in Assergi, Italy. These data represent an exposure of 11.83 kg yr or 91 mole-years of {sup 130}Te. No evidence for 0 {nu}{beta}{beta}-decay was observed and a limit of T{sub 1/2}{sup 0} {sup {nu}}({sup 130}Te){>=}3.0x10{sup 24} y (90% CL) is set. This corresponds to an upper limit on the effective mass, , between 0.19 and 0.68 eV when analyzed with the many published nuclear structure calculations. In the context of these nuclear models, the values fall within the range corresponding to the claim of evidence of 0 {nu}{beta}{beta}-decay by H. V. Klapdor-Kleingrothaus et al. The experiment continues to acquire data.

Arnaboldi, C.; Brofferio, C.; Capelli, S.; Clemenza, M.; Fiorini, E.; Nucciotti, A.; Pavan, M.; Sisti, M. [Dipartimento di Fisica dell'Universita di Milano-Bicocca, I-20126 Milano (Italy); Sezione INFN di Milano-Bicocca, I-20126 Milano (Italy); Artusa, D. R.; Avignone III, F. T.; Bandac, I.; Creswick, R. J.; Farach, H. A.; Rosenfeld, C. [Department of Physics and Astronomy, University of South Carolina, Columbia, SC 29208 (United States); Balata, M.; Bucci, C.; Giachero, A.; Gorla, P.; Nisi, S. [INFN Laboratori Nazionali del Gran Sasso, I-67010, Assergi (L'Aquila) (Italy); Barucci, M. [Dipartimento di Fisica dell'Universita di Firenze, I-50019 Firenze (Italy); Sezione INFN di Firenze, I-50019, Firenze (Italy)] (and others)

2008-09-15T23:59:59.000Z

60

Comparing radiative and recoil corrections in neutron beta-decay and inverse beta-decay  

E-Print Network (OSTI)

The inverse $\\beta$-decay reaction, anti-nu_e + p --> e^+ + n, for low-energy anti-neutrinos coming from nuclear reactors is of great current interest in connection with high-precision measurements of the neutrino mixing angle $\\theta_{13}$. We have previously derived analytic expressions, up to next-to-leading order in heavy-baryon chiral perturbation theory, for the radiative corrections (RCs) and the nucleon-recoil corrections both for this reaction and for the related neutron $\\beta$-decay process. We investigate here the numerical consequences of these analytic expressions. We show that the recoil corrections are small for neutron $\\beta$-decay, but for inverse $\\beta$-decay, the recoil corrections are comparable in size to the RCs for typical energies of reactor anti-neutrinos, and they have opposite signs. It turns out that the RCs and the recoil corrections exhibit very different dependences on the neutrino energy.

Raha, U; Kubodera, K

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Comparing radiative and recoil corrections in neutron beta-decay and inverse beta-decay  

E-Print Network (OSTI)

The inverse $\\beta$-decay reaction, anti-nu_e + p --> e^+ + n, for low-energy anti-neutrinos coming from nuclear reactors is of great current interest in connection with high-precision measurements of the neutrino mixing angle $\\theta_{13}$. We have previously derived analytic expressions, up to next-to-leading order in heavy-baryon chiral perturbation theory, for the radiative corrections (RCs) and the nucleon-recoil corrections both for this reaction and for the related neutron $\\beta$-decay process. We investigate here the numerical consequences of these analytic expressions. We show that the recoil corrections are small for neutron $\\beta$-decay, but for inverse $\\beta$-decay, the recoil corrections are comparable in size to the RCs for typical energies of reactor anti-neutrinos, and they have opposite signs. It turns out that the RCs and the recoil corrections exhibit very different dependences on the neutrino energy.

U. Raha; F. Myhrer; K. Kubodera

2012-07-18T23:59:59.000Z

62

Large-Scale Calculations of the Double-Beta Decay of 76Ge, 130Te, 136Xe, and 150Nd in the Deformed Self-Consistent Skyrme Quasiparticle Random-Phase Approximation  

E-Print Network (OSTI)

We use the axially-deformed Skyrme Quasiparticle Random-Phase Approximation (QRPA) together with the SkM* energy-density functional, both as originally presented and with the time-odd part adjusted to reproduce the Gamow-Teller resonance energy in 208Pb, to calculate the matrix elements governing the neutrinoless double-beta decay of 76Ge, 130Te, 136Xe, and 150Nd. Our matrix elements in 130Te and 136Xe are significantly smaller than those of previous QRPA calculations, primarily because of the difference in pairing or deformation between the initial and final nuclei. In 76Ge and 150Nd our results are similar to those of less computationally intensive QRPA calculations. We suspect the 76Ge result, however, because we are forced to use a spherical ground-state, even though the HFB indicates a deformed minimum.

M. T. Mustonen; J. Engel

2013-01-29T23:59:59.000Z

63

Exclusive Double Charmonium Production from $?$ Decay  

E-Print Network (OSTI)

The exclusive decay of $\\Upsilon$ to a vector plus pseudoscalar charmonium is studied in perturbative QCD. The corresponding branching ratios are predicted to be of order $10^{-6}$ for first three $\\Upsilon$ resonances, and we expect these decay modes should be discovered in the prospective high-luminosity $e^+e^-$ facilities such as super $B$ experiment. As a manifestation of the short-distance loop contribution, the relative phases among strong, electromagnetic and radiative decay amplitudes can be deduced. It is particularly interesting to find that the relative phase between strong and electromagnetic amplitudes is nearly orthogonal. The resonance-continuum interference effect for double charmonium production near various $\\Upsilon$ resonances in $e^+e^-$ annihilation is addressed.

Yu Jia

2007-06-25T23:59:59.000Z

64

The Particle Adventure | Particle decays and annihiliations | Neutron beta  

NLE Websites -- All DOE Office Websites (Extended Search)

Particle decays and annihiliations > Neutron beta Particle decays and annihiliations > Neutron beta decays Neutron beta decays A neutron (udd) decays to a proton (uud), an electron, and an antineutrino. This is called neutron beta decay. (The term beta ray was used for electrons in nuclear decays because they didn't know they were electrons!) Frame 1: The neutron (charge = 0) made of up, down, down quarks. Frame 2: One of the down quarks is transformed into an up quark. Since the down quark has a charge of -1/3 and and the up quark has a charge of 2/3, it follows that this process is mediated by a virtual W- particle, which carries away a (-1) charge (thus charge is conserved!) Frame 3: The new up quark rebounds away from the emitted W-. The neutron now has become a proton. Frame 4: An electron and antineutrino emerge from the virtual W- boson.

65

Competition between alpha-decay and beta-decay for Heavy and Superheavy Nuclei  

E-Print Network (OSTI)

In this work, the $\\beta$-stable region for Z $\\geq$ 90 is proposed. The calculated $\\beta$-stable nuclei in the $\\beta$-stable region are in good agreement with the ones obtained by M\\"{o}ller \\emph{et al}.. The half-lives of the nuclei close to the $\\beta$-stable region are calculated and the competition between $\\alpha$-decay and $\\beta$-decay is systematically investigated. The calculated half-lives and the suggested decay modes are well in line with the experimental results. The predictions for half-lives and decay modes of the nuclei with Z = 107$-$110 are presented.

Zongqiang Sheng; Liangping Shu; Ying Meng; Jigang Hu; Jianfa Qian

2014-01-16T23:59:59.000Z

66

Nd double beta decay search with SNO +  

Science Conference Proceedings (OSTI)

SNO + is a follow up experiment of SNO replacing the heavy water by a liquid scintillator. Especially

Kai Zuber; (on behalf of the SNO+ collaboration)

2007-01-01T23:59:59.000Z

67

Beta decay of Neutron-Rich 53-56Ca  

E-Print Network (OSTI)

Beta-decay properties of neutron-rich Ca isotopes have been obtained. Half-life values were determined for the first time for 54Ca [86(7) ms], 55Ca [22(2) ms], and 56Ca [11(2) ms]. The half-life of 230(6) ms deduced for 53Ca is significantly longer than reported previously, where the decay chain 53K -> 53Ca -> 53Sc was considered. A delayed gamma ray with energy 247 keV as identified following beta decay of 54Ca, and is proposed to depopulate the first 1+ level in 54Sc. The beta-decay properties compare favorably with the results of shell model calculations completed in the full pf-space with the GXPF1 interaction. The half-lives of the neutron-rich Ca isotopes are also compared with gross beta-decay theory. The systematic trend of the neutron-rich Ca half-lives is consistent with the presence of a subshell gap at N=32.

P. F. Mantica; R. Broda; H. L. Crawford; A. Damaske; B. Fornal; A. A. Hecht; C. Hoffman; M. Horoi; N. Hoteling; R. V. F. Janssens; J. Pereira; J. S. Pinter; J. B. Stoker; S. L. Tabor; T. Sumikama; W. B. Walters; X. Wang; S. Zhu

2008-01-07T23:59:59.000Z

68

Beta decay of Neutron-Rich 53-56Ca  

E-Print Network (OSTI)

Beta-decay properties of neutron-rich Ca isotopes have been obtained. Half-life values were determined for the first time for 54Ca [86(7) ms], 55Ca [22(2) ms], and 56Ca [11(2) ms]. The half-life of 230(6) ms deduced for 53Ca is significantly longer than reported previously, where the decay chain 53K -> 53Ca -> 53Sc was considered. A delayed gamma ray with energy 247 keV as identified following beta decay of 54Ca, and is proposed to depopulate the first 1+ level in 54Sc. The beta-decay properties compare favorably with the results of shell model calculations completed in the full pf-space with the GXPF1 interaction. The half-lives of the neutron-rich Ca isotopes are also compared with gross beta-decay theory. The systematic trend of the neutron-rich Ca half-lives is consistent with the presence of a subshell gap at N=32.

Mantica, P F; Crawford, H L; Damaske, A; Fornal, B; Hecht, A A; Hoffman, C; Horoi, M; Hoteling, N; Janssens, R V F; Pereira, J; Pinter, J S; Stoker, J B; Tabor, S L; Sumikama, T; Walters, W B; Wang, X; Zhu, S

2008-01-01T23:59:59.000Z

69

New Limit on Time-Reversal Violation in Beta Decay  

Science Conference Proceedings (OSTI)

We report the results of an improved determination of the triple correlation DP{center_dot}(p{sub e}xp{sub v}) that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to the standard model. Our result is D=[-0.96{+-}1.89(stat){+-}1.01(sys)]x10{sup -4}. The corresponding phase between g{sub A} and g{sub V} is {phi}{sub AV}=180.013 deg. {+-}0.028 deg. (68% confidence level). This result represents the most sensitive measurement of D in nuclear {beta} decay.

Mumm, H. P. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); CENPA and Physics Department, University of Washington, Seattle, Washington 98195 (United States); Chupp, T. E.; Cooper, R. L.; Coulter, K. P. [Physics Department, University of Michigan, Ann Arbor, Michigan, 48104 (United States); Freedman, S. J.; Fujikawa, B. K. [Physics Department, University of California at Berkeley and Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Garcia, A. [CENPA and Physics Department, University of Washington, Seattle, Washington 98195 (United States); Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Jones, G. L. [Physics Department, Hamilton College, Clinton, New York 13323 (United States); Nico, J. S.; Thompson, A. K. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Trull, C. A.; Wietfeldt, F. E. [Physics Department, Tulane University, New Orleans, Louisiana 70118 (United States); Wilkerson, J. F. [Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); CENPA and Physics Department, University of Washington, Seattle, Washington 98195 (United States)

2011-09-02T23:59:59.000Z

70

Nuclear Chemistry Beta decay of 71,73  

E-Print Network (OSTI)

34 Nuclear Chemistry Beta decay of 71,73 Co: probing single-parti- cle states approaching doubly of primary interest are the nuclear magnetic dipole moment and nuclear electric quadrupole moment. The dipole/or neutrons in the nucleus. The dipole moment provides information on the nuclear quantum structure

Mantica, Paul F.

71

Can the beta decay of neutral kaons be observed?  

E-Print Network (OSTI)

The rate of the beta decay of neutral kaons is calculated within the meson dominance approach taking into account the relation between the KK\\rho and \\pi\\pi\\rho coupling constants which follows from the vector meson dominance in electromagnetic interactions and isospin symmetry. The decay rate transforms into the following branching fraction summed over the charge states indicated: B(K0L -> K+- e-+ nu)=(2.53+-0.10)x10^{-9}. The error is dominated by our estimate of isospin violating effects. Experimental aspects of such a measurement are discussed.

Peter Lichard; Julia Thompson

2000-04-25T23:59:59.000Z

72

Reduced Beta Decay Rates of Iron Isotopes for Supernova Physics  

SciTech Connect

During the late phases of stellar evolution beta decay on iron isotopes, in the core of massive stars, plays a crucial role in the dynamics of core-collapse. The beta decay contributes in maintaining a 'respectable' lepton-to-baryon ratio (PSI{sub e}) of the core prior to collapse which results in a larger shock energy to power the explosion. It is indeed a fine tuning of the parameter PSI{sub e} at various stages of supernova physics which can lead to a successful transformation of the collapse into an explosion. The calculations presented here might help in fine-tuning of PSI{sub e} for the collapse simulators of massive stars.

Nabi, Jameel-Un [Faculty of Engineering Sciences, GIK Institute of Engineering Sciences and Technology, Topi 23460, N.W.F.P. (Pakistan)

2009-07-07T23:59:59.000Z

73

Precision Measurement of the Neutron Beta-Decay Asymmetry  

E-Print Network (OSTI)

A new measurement of the neutron $\\beta$-decay asymmetry $A_0$ has been carried out by the UCNA collaboration using polarized ultracold neutrons (UCN) from the solid deuterium UCN source at the Los Alamos Neutron Science Center (LANSCE). Improvements in the experiment have led to reductions in both statistical and systematic uncertainties leading to $A_0 = -0.11954(55)_{\\rm stat.}(98)_{\\rm syst.}$, corresponding to the ratio of axial-vector to vector coupling $\\lambda \\equiv g_A/g_V = -1.2756(30)$.

Mendenhall, M P; Bagdasarova, Y; Berguno, D B; Broussard, L J; Carr, R; Clayton, S; Currie, S; Ding, X; García, A; Geltenbort, P; Hickerson, K P; Hoagland, J; Hogan, G E; Holley, A T; Hong, R; Ito, T M; Filippone, B W; Knecht, A; Liu, C -Y; Liu, J L; Makela, M; Mammei, R R; Martin, J W; Melconian, D; Moore, S D; Morris, C L; Galván, A Pérez; Picker, R; Pitt, M L; Plaster, B; Rios, R; Saunders, A; Seestrom, S J; Sondheim, W E; Tatar, E; Vogelaar, R B; VornDick, B; Wrede, C; Young, A R; Zeck, B A

2012-01-01T23:59:59.000Z

74

Precision Measurement of the Neutron Beta-Decay Asymmetry  

E-Print Network (OSTI)

A new measurement of the neutron $\\beta$-decay asymmetry $A_0$ has been carried out by the UCNA collaboration using polarized ultracold neutrons (UCN) from the solid deuterium UCN source at the Los Alamos Neutron Science Center (LANSCE). Improvements in the experiment have led to reductions in both statistical and systematic uncertainties leading to $A_0 = -0.11954(55)_{\\rm stat.}(98)_{\\rm syst.}$, corresponding to the ratio of axial-vector to vector coupling $\\lambda \\equiv g_A/g_V = -1.2756(30)$.

M. P. Mendenhall; R. W. Pattie Jr; Y. Bagdasarova; D. B. Berguno; L. J. Broussard; R. Carr; S. Currie; X. Ding; B. W. Filippone; A. García; P. Geltenbort; K. P. Hickerson; J. Hoagland; A. T. Holley; R. Hong; T. M. Ito; A. Knecht; C. -Y. Liu; J. L. Liu; M. Makela; R. R. Mammei; J. W. Martin; D. Melconian; S. D. Moore; C. L. Morris; A. Pérez Galván; R. Picker; M. L. Pitt; B. Plaster; J. C. Ramsey; R. Rios; A. Saunders; S. J. Seestrom; E. I. Sharapov; W. E. Sondheim; E. Tatar; R. B. Vogelaar; B. VornDick; C. Wrede; A. R. Young; B. A. Zeck

2012-10-26T23:59:59.000Z

75

Inverse beta decay reaction in $^{232}$Th and $^{233}$U fission antineutrino flux  

E-Print Network (OSTI)

Energy spectra of antineutrinos coming from $^{232}$Th and $^{233}$U neutron-induced fission are calculated, relevant inverse beta decay $\\bar{{\

G. Domogatski; V. Kopeikin; L. Mikaelyan; V. Sinev

2004-03-15T23:59:59.000Z

76

Electron Capture Reactions and Beta Decays in Steller Environments  

SciTech Connect

Electron capture reactions on Ni and Co isotopes are investigated by shell model calculations in steller environments. The capture rates depend sensitively on the distribution of the Gamow-Teller (GT) strength. The capture rates obtained by using GXPF1J Hamiltonian for fp-shell are found to be consistent with the rates obtained from experimental GT strength in {sup 58}Ni and {sup 60}Ni. Capture rates in Co isotopes, where there were large discrepancies among previous calculations, are also investigated. Beta decays of the N = 126 isotones are studied by shell model calculations taking into account both the GT and first-forbidden (FF) transitions. The FF transitions are found to be important to reduce the half-lives by twice to several times of those by the GT contributions only. Implications of the short half-lives of the waiting point nuclei on the r-process nucleosynthesis are discussed for various astrophysical conditions.

Suzuki, T. [Department of Physics and Graduate School of Integrated Basic Sciences, College of Humanities and Sciences, Nihon University, Sakurajosui 3-25-40, Setagaya-ku, Tokyo 156-8550, Japan and Center for Nuclear Study, University of Tokyo, Hirosawa, Wako-shi, Saitama, 351-0198 (Japan); Mao, H. [Graduate School of Integrated Basic Sciences, Nihon University, Sakurajosui-3-25-40, Setagaya-ku, Tokyo 156-8550, Japan and ENSPS, Pole API-Parc d'Innovation, Boulevard Sebastien Brant, BP 10413, 67412 ILLKIRCH CEDEXL (France); Honma, M. [Center for Mathematical Sciences, University of Aizu, Aizu-Wakamatsu, Fukushima 965-8580 (Japan); Yoshida, T. [Department of Astronomy, Graduate School of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kajino, T. [Department of Astronomy, Graduate School of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan) and National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Otsuka, T. [Department of Physics and Center for Nuclear Study, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan) and RIKEN, Hirosawa, Wako-shi, Saitama 351-0198 (Japan)

2011-10-28T23:59:59.000Z

77

Uncertainties in nuclear transition matrix elements for neutrinoless {beta}{beta} decay  

SciTech Connect

Uncertainties in nuclear transition matrix elements M{sup (0{nu})} and M{sub N}{sup (0{nu})} due to the exchange of light and heavy Majorana neutrinos, respectively have been estimated by calculating sets of twelve nuclear transition matrix elements for the neutrinoless {beta}{beta} decay of {sup 94,96}Zr, {sup 98,100}Mo, {sup 104}Ru, {sup 110}Pd, {sup 128,130}Te and {sup 150}Nd isotopes in the case of 0{sup +}{yields}0{sup +} transition by considering four different parameterizations of a Hamiltonian with pairing plus multipolar effective two-body interaction and three different parameterizations of Jastrow short range correlations. Exclusion of nuclear transition matrix elements calculated with the Miller-Spencer parametrization reduces the uncertainties by 10%-15%.

Rath, P. K. [Department of Physics, University of Lucknow, Lucknow-226007 (India)

2011-12-16T23:59:59.000Z

78

Decoding Beta-Decay Systematics: A Global Statistical Model for Beta^- Halflives  

E-Print Network (OSTI)

Statistical modeling of nuclear data provides a novel approach to nuclear systematics complementary to established theoretical and phenomenological approaches based on quantum theory. Continuing previous studies in which global statistical modeling is pursued within the general framework of machine learning theory, we implement advances in training algorithms designed to improved generalization, in application to the problem of reproducing and predicting the halflives of nuclear ground states that decay 100% by the beta^- mode. More specifically, fully-connected, multilayer feedforward artificial neural network models are developed using the Levenberg-Marquardt optimization algorithm together with Bayesian regularization and cross-validation. The predictive performance of models emerging from extensive computer experiments is compared with that of traditional microscopic and phenomenological models as well as with the performance of other learning systems, including earlier neural network models as well as the support vector machines recently applied to the same problem. In discussing the results, emphasis is placed on predictions for nuclei that are far from the stability line, and especially those involved in the r-process nucleosynthesis. It is found that the new statistical models can match or even surpass the predictive performance of conventional models for beta-decay systematics and accordingly should provide a valuable additional tool for exploring the expanding nuclear landscape.

N. J. Costiris; E. Mavrommatis; K. A. Gernoth; J. W. Clark

2008-06-17T23:59:59.000Z

79

Superallowed nuclear beta decay: Precision measurements for basic physics  

Science Conference Proceedings (OSTI)

For 60 years, superallowed 0{sup +}{yields}0{sup +} nuclear beta decay has been used to probe the weak interaction, currently verifying the conservation of the vector current (CVC) to high precision ({+-}0.01%) and anchoring the most demanding available test of the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix ({+-}0.06%), a fundamental pillar of the electroweak standard model. Each superallowed transition is characterized by its ft-value, a result obtained from three measured quantities: the total decay energy of the transition, its branching ratio, and the half-life of the parent state. Today's data set is composed of some 150 independent measurements of 13 separate superallowed transitions covering a wide range of parent nuclei from {sup 10}C to {sup 74}Rb. Excellent consistency among the average results for all 13 transitions - a prediction of CVC - also confirms the validity of the small transition-dependent theoretical corrections that have been applied to account for isospin symmetry breaking. With CVC consistency established, the value of the vector coupling constant, G{sub V}, has been extracted from the data and used to determine the top left element of the CKM matrix, V{sub ud}. With this result the top-row unitarity test of the CKM matrix yields the value 0.99995(61), a result that sets a tight limit on possible new physics beyond the standard model. To have any impact on these fundamental weak-interaction tests, any measurement must be made with a precision of 0.1% or better - a substantial experimental challenge well beyond the requirements of most nuclear physics measurements. I overview the current state of the field and outline some of the requirements that need to be met by experimentalists if they aim to make measurements with this high level of precision.

Hardy, J. C. [Cylotron Institute, Texas A and M University, College station, TX, 77843-3366 (United States)

2012-11-20T23:59:59.000Z

80

Decoding Beta-Decay Systematics: A Global Statistical Model for Beta^- Halflives  

E-Print Network (OSTI)

Statistical modeling of nuclear data provides a novel approach to nuclear systematics complementary to established theoretical and phenomenological approaches based on quantum theory. Continuing previous studies in which global statistical modeling is pursued within the general framework of machine learning theory, we implement advances in training algorithms designed to improved generalization, in application to the problem of reproducing and predicting the halflives of nuclear ground states that decay 100% by the beta^- mode. More specifically, fully-connected, multilayer feedforward artificial neural network models are developed using the Levenberg-Marquardt optimization algorithm together with Bayesian regularization and cross-validation. The predictive performance of models emerging from extensive computer experiments is compared with that of traditional microscopic and phenomenological models as well as with the performance of other learning systems, including earlier neural network models as well as th...

Costiris, N J; Gernoth, K A; Clark, J W

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Analysis of an esoteric interpretation of a threshold in beta decay  

SciTech Connect

A threshold associated with a small mixing of a heavy neutrino in beta decay cannot be interpreted as due to the production of a fictitious neutral scalar in conjunction with a light neutrino.

Karl, G.; Novikov, V.; Simpson, J.J. (Department of Physics, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada))

1992-11-01T23:59:59.000Z

82

Beta-decay spectroscopy relevant to the r-process nucleosynthesis  

Science Conference Proceedings (OSTI)

A scientific program of beta-decay spectroscopy relevant to r-process nucleosynthesis has been started using high intensity U-beam at the RIBF. The first results of {beta}-decay half-lives of very neutron-rich Kr to Tc nuclides, all of which lie close to the r-process path, suggest a systematic enhancement of the the {beta}-decay rates of the Zr and Nb isotopes around A110 with respect to the predictions of the deformed quasiparticle-random-phase-approximation model (FRDM + QRPA). An impact of the results on the astrophysical r-process is discussed together with the future perspective of the {beta}-decay spectroscopy with the EURICA.

Nishimura, Shunji [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Collaboration: RIBF Decay Collaboration

2012-11-12T23:59:59.000Z

83

Half-Life for Double Beta-Decay  

E-Print Network (OSTI)

Nuclear Energy Series, Plutonium Proje-ct Record Vblo 14B "Huolear Energy Series, Plutonium Project Record Yolo 14B "extracting and separating the plutonium fraction by chemical

Levine, C.A.; Ghiorso, A.; Seaborg, G.T.

2008-01-01T23:59:59.000Z

84

Inverse Beta Decay in a Nonequilibrium Antineutrino Flux from a Nuclear Reactor  

E-Print Network (OSTI)

The evolution of the reactor antineutrino spectrum toward equilibrium above the inverse beta-decay threshold during the reactor operating period and the decay of residual antineutrino radiation after reactor shutdown are considered. It is found that, under certain conditions, these processes can play a significant role in experiments seeking neutrino oscillations.

V. I. Kopeikin; L. A. Mikaelyan; V. V. Sinev

2001-10-23T23:59:59.000Z

85

1 Inverse Beta Decay in a Nonequilibrium Antineutrino Flux from a Nuclear Reactor  

E-Print Network (OSTI)

The evolution of the reactor antineutrino spectrum toward equilibrium above the inverse beta-decay threshold during the reactor operating period and the decay of residual ¯?e, radiation after reactor shutdown are considered. It is found that, under certain conditions, these processes can play a significant role in experiments seeking neutrino oscillations. 1.

V. I. Kopeikin A; L. A. Mikaelyan A; V. V. Sinev A

2001-01-01T23:59:59.000Z

86

Beta-decay properties of Zr and Mo neutron-rich isotopes  

E-Print Network (OSTI)

Gamow-Teller strength distributions, beta-decay half-lives, and beta-delayed neutron emission are investigated in neutron-rich Zr and Mo isotopes within a deformed quasiparticle random-phase approximation. The approach is based on a self-consistent Skyrme Hartree-Fock mean field with pairing correlations and residual separable particle-hole and particle-particle forces. Comparison with recent measurements of half-lives stresses the important role that nuclear deformation plays in the description of beta-decay properties in this mass region.

Sarriguren, P

2010-01-01T23:59:59.000Z

87

Super-allowed beta-decay rates in 1d5/2 shell in Coriolis coupling model  

E-Print Network (OSTI)

The expression for super-allowed beta-decay transition rates have been derived within the context of Coriolis coupling model. The derived expressions, valid for the beta-decay between any two mirror nuclei, has been applied to calculate super-allowed beta-decay transition rates of 21Na, 21Mg, 21Al, and 21Si. The calculated rates agree well with the data and the calculations done using the shell model with configuration admixture.

M. Sultan Parvez; F. Bary Malik

2009-04-03T23:59:59.000Z

88

A Global Model of $\\beta^-$-Decay Half-Lives Using Neural Networks  

E-Print Network (OSTI)

Statistical modeling of nuclear data using artificial neural networks (ANNs) and, more recently, support vector machines (SVMs), is providing novel approaches to systematics that are complementary to phenomenological and semi-microscopic theories. We present a global model of $\\beta^-$-decay halflives of the class of nuclei that decay 100% by $\\beta^-$ mode in their ground states. A fully-connected multilayered feed forward network has been trained using the Levenberg-Marquardt algorithm, Bayesian regularization, and cross-validation. The halflife estimates generated by the model are discussed and compared with the available experimental data, with previous results obtained with neural networks, and with estimates coming from traditional global nuclear models. Predictions of the new neural-network model are given for nuclei far from stability, with particular attention to those involved in r-process nucleosynthesis. This study demonstrates that in the framework of the $\\beta^-$-decay problem considered here, ...

Costiris, N; Gernoth, K A; Mavrommatis, E

2007-01-01T23:59:59.000Z

89

On the possibility to measure 0{nu}{beta}{beta}-decay nuclear matrix element for {sup 48}Ca  

SciTech Connect

As shown in Ref. [2], the Fermi part M{sub F}{sup 0{nu}} of the total 0{nu}{beta}{beta}-decay nuclear matrix element M{sup 0{nu}} can be related to the single Fermi transition matrix element between the isobaric analog state (IAS) of the ground state of the initial nucleus and the ground state of the final nucleus. The latter matrix element could be measured in charge-exchange reactions. Here we discuss a possibility of such a measurement for {sup 48}Ca and estimate the cross-section of the reaction {sup 48}Ti(n,p){sup 48}Sc(IAS).

Rodin, Vadim [Institute fuer Theoretische Physik der Universitaet Tuebingen, D-72076 Tuebingen (Germany)

2011-12-16T23:59:59.000Z

90

First Direct Double- Decay Q-Value Measurement of 82Se in Support of Understanding the Nature of the Neutrino  

Science Conference Proceedings (OSTI)

In anticipation of results from current and future double- decay studies, we report a measurement resulting in a 82Se double- decay Q value of 2997.9(3) keV, an order of magnitude more precise than the currently accepted value. We also present preliminary results of a calculation of the 82Se neutrinoless double- decay nuclear matrix element that corrects in part for the small size of the shell model single-particle space. The results of this work are important for designing next generation double- decay experiments and for the theoretical interpretations of their observations.

Lincoln, David L. [NSCL, Michigan State University, East Lansing; Holt, Jason D. [Technische Univ. Darmstadt/GSI/UTK/ORNL; Bollen, Georg [NSCL, Michigan State University, East Lansing; Brodeur, Maxime [NSCL, Michigan State University, East Lansing; Bustabad, Scott [NSCL, Michigan State University, East Lansing; Engel, Jonathan [University of North Carolina, Chapel Hill; Novario, Samuel J. [NSCL, Michigan State University, East Lansing; Redshaw, Matthew [NSCL, Michigan State Univ.,/Central Michigan Univ.-Mt. Pleasant; Ringle, Ryan [NSCL, Michigan State University, East Lansing; Schwarz, Stefan [NSCL, Michigan State University, East Lansing

2013-01-01T23:59:59.000Z

91

Proton Recoil Energy and Angular Distribution of Neutron Radiative Beta Decay  

E-Print Network (OSTI)

We analyse the proton recoil energy and angular distribution of the radiative beta-decay of the neutron to leading order in the large baryon mass expansion by taking into account the contributions of the proton-photon correlations. We show that the account for the proton-photon correlations does not contradict the description of the radiative corrections to the lifetime of the neutron and the proton recoil energy spectrum of the neutron beta-decay in terms of the functions (\\alpha/\\pi) g_n(E_e) and (\\alpha/\\pi) f_n(E_e), where E_e is the electron energy. In addition we find that the contributions of the proton-photon correlations in the radiative beta-decay of the neutron to the proton recoil asymmetry C are of order 10^(-4). They make the contributions of the radiative corrections to the proton recoil asymmetry C symmetric with respect to a change A_0 B_0, where A_0 and B_0 are the correlation coefficients of the neutron beta-decay.

A. N. Ivanov; R. Hollwieser; N. I. Troitskaya; M. Wellenzohn

2013-06-19T23:59:59.000Z

92

Evaluation of radioactive background rejection in 76Ge neutrino-lessdouble-beta decay experiments using a highly segmented HPGe detector  

Science Conference Proceedings (OSTI)

A highly segmented coaxial HPGe detector was operated in a low background counting facility for over 1 year to experimentally evaluate possible segmentation strategies for the proposed Majorana neutrino-less double-beta decay experiment. Segmentation schemes were evaluated on their ability to reject multi-segment events while retaining single-segment events. To quantify a segmentation scheme's acceptance efficiency the percentage of peak area due to single segment events was calculated for peaks located in the energy region 911-2614 keV. Single interaction site events were represented by the double-escape peak from the 2614 keV decay in {sup 208}Tl located at 1592 keV. In spite of its prototypical nature, the detector performed well under realistic operating conditions and required only minimal human interaction. Though the energy resolution for events with interactions in multiple segments was impacted by inter-segment cross-talk, the implementation of a cross-talk correlation matrix restored acceptable resolution. Additionally, simulations utilizing the MaGe simulation package were performed and found to be in good agreement with experimental observations verifying the external nature of the background radiation.

Chan, Yuen-Dat; Campbell, D.B.; Vetter, K.; Henning, R.; Lesko, K.; Chan, Y.D.; Poon, A.W.P.; Perry, M.; Hurley, D.; Smith, A.R.

2007-02-05T23:59:59.000Z

93

Observation of beta decay of In-115 to the first excited level of Sn-115  

E-Print Network (OSTI)

In the context of the LENS R&D solar neutrino project, the gamma spectrum of a sample of metallic indium was measured using a single experimental setup of 4 HP-Ge detectors located underground at the Gran Sasso National Laboratories (LNGS), Italy. A gamma line at the energy (497.48 +/- 0.21) keV was found that is not present in the background spectrum and that can be identified as a gamma quantum following the beta decay of In-115 to the first excited state of Sn-115 (9/2+ --> 3/2+). This decay channel of In-115, which is reported here for the first time, has an extremely low Q-value, Q = (2 +/- 4) keV, and has a much lower probability than the well-known ground state-ground state transition, being the branching ratio b = (1.18 +/- 0.31) 10^-6. This could be the beta decay with the lowest known Q-value. The limit on charge non-conserving beta decay of In-115 is set at 90% C.L. as tau > 4.1 10^20 y.

C. M. Cattadori; M. De Deo; M. Laubenstein; L. Pandola; V. I. Tretyak

2004-07-16T23:59:59.000Z

94

The {beta}-Decay Properties of Scissors Mode 1{sup +} States in {sup 164}Er  

Science Conference Proceedings (OSTI)

The beta decay properties of collective I{sup {pi}}K = 1{sup +}1 states in doubly even deformed {sup 164}Er nuclei are investigated in the framework of the rotational invariant random-phase approximation. It is shown that an essential decrease of the rate of the allowed {beta}-decay to the excited 1{sup +}-states as compared with that to the ground state may be due to the orbital nature of the states. The model Hamiltonian includes restoring rotational invariance of the deformed single particle Hamiltonian forces and the spin-spin interactions. The analytical expressions for the Gamov-Teller (G-T) and Fermi (F) decay matrix elements are derived. The single-particle energies were obtained from the Warsaw deformed Woods-Saxon potential with deformation parameter {delta}{sub 2} = 0.24. The numerical results for {beta}{sup +} transition from {sup 164}Tm to {sup 164}Er indicate the importance of using rotational invariant Hamiltonian to explain experimental data.

Yildirim, Z.; Kuliev, A.; Ozkan, S. [Sakarya University, Department of Physics, 54100, Sakarya (Turkey); Guliyev, E. [Institute of Physics, Academy of Sciences, H. Cavid Avenue 33, Baku (Azerbaijan); Institut fur Kernphysik, Technische Universitat Darmstadt, Darmstadt (Germany)

2008-11-11T23:59:59.000Z

95

Beta dependence of electron heating in decaying whistler turbulence: Particle-in-cell simulations  

SciTech Connect

Two-dimensional particle-in-cell simulations have been carried out to study electron beta dependence of decaying whistler turbulence and electron heating in a homogeneous, collisionless magnetized plasma. Initially, applied whistler fluctuations at relatively long wavelengths cascade their energy into shorter wavelengths. This cascade leads to whistler turbulence with anisotropic wavenumber spectra which are broader in directions perpendicular to the background magnetic field than in the parallel direction. Comparing the development of whistler turbulence at different electron beta values, it is found that both the wavenumber spectrum anisotropy and electron heating anisotropy decrease with increasing electron beta. This indicates that higher electron beta reduces the perpendicular energy cascade of whistler turbulence. Fluctuation energy dissipation by electron Landau damping responsible for the electron parallel heating becomes weaker at higher electron beta, which leads to more isotropic heating. It suggests that electron kinetic processes are important in determining the properties of whistler turbulence. This kinetic property is applied to discuss the generation of suprathermal strahl electron distributions in the solar wind.

Saito, S. [National Institute of Information and Communications Technology 4-2-1, Nukui-Kitamachi, Koganei, Tokyo 184-8795 (Japan); Peter Gary, S. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2012-01-15T23:59:59.000Z

96

BETA-DECAY MATRIX ELEMENTS IN Sb$sup 12$$sup 2$  

SciTech Connect

An electronic computer has been used to investigate the six nuclear matrix elements which enter into the 2/sup -/ to 2/sup +/ 1.40-Mev beta transition in the decay of Sb/sup 122/. Data from beta-gamma angular correlation, beta-circularly polarized gamma angular correlation, nuclear orientation, and nuclear resonance experiments were used in this analysis. As a further aid, the Feenberg-Ahrens relations between certain of the nuclear matrix elements were employed to catalog the solutions and to simplify the search problem. In order to discover how the remaining ambiguity of these solutions could most easily be reduced, for each of the solutions calculations were made of the predicted results of all possible experiments on this beta transition. These calculations show how sufficient experimental data can be obtained to determine unambiguously all six nuclear matrix elements. In an appendix all the theoretical formulas which give the experimental observables for a first forbidden 2/sup -/ to S/sup +/ beta transition in terms of the nuclear matrix ele

Pipkin, F.M.; Sanderson, J.; Weyhmann, W.

1963-03-15T23:59:59.000Z

97

Beta Decay of the Proton-Rich Nuclei 102Sn and 104Sn  

Science Conference Proceedings (OSTI)

The {beta} decays of {sup 102}Sn and {sup 104}Sn were studied by using high-resolution germanium detectors as well as a Total Absorption Spectrometer (TAS). For {sup 104}Sn, with three new {beta}-delayed {gamma}-rays identified, the total Gamow-Teller strength (BGT) value of 2.7(3) was obtained. For {sup 102}Sn, the {gamma}-{gamma} coincidence data were collected for the first time, allowing us to considerably extend the decay scheme. This scheme was used to unfold the TAS data and to deduce a BGT value of 4.2(8) for this decay. This result is compared to shell model predictions, yielding a hindrance factor of 3.6(7) in agreement with those obtained previously for {sup 98}Cd and {sup 100}In. Together with the latter two, {sup 102}Sn completes the triplet of Z {le} 50, N {ge} 50 nuclei with two proton holes, one proton hole and one neutron particle, and two neutron particles with respect to the doubly magic {sup 100}Sn core.

Karny, M. [University of Warsaw; Batist, L. [St. Petersburg Nuclear Physics Institute; Banu, A. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Becker, F. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Blazhev, A. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Brown, B. A. [Michigan State University, East Lansing; Bruchle, W. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Doring, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Faestermann, T. [Technische Universitat Munchen; Gorska, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Grawe, H. [GSI-Hemholtzzentrum fur Schwerionenforschung, Darmstadt, Germany; Janas, Z. [University of Warsaw; Jungclaus, A. [Universidad Autonoma de Madrid, Madrid; Kavatsyuk, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kavatsyuk, O. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kirchner, R. [Gesellschaft fur Schwerionenforschung (GSI), Germany; La Commara, M. [Universita Federico II and INFN Napoli; Mandal, S. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Mazzocchi, C. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Miernik, K. [University of Warsaw; Mukha, I. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Muralithar, S. [University of Warsaw; Plettner, C. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Plochocki, A. [University of Warsaw; Roeckl, E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Romoli, M. [Universita Federico II and INFN Napoli; Rykaczewski, Krzysztof Piotr [ORNL; Schadel, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Schmidt, K. [University of Warsaw; Schwengner, R. [University of Warsaw; Zylicz, J. [University of Warsaw

2006-01-01T23:59:59.000Z

98

Limit on electron neutrino mass from observation of the beta decay of molecular tritium  

Science Conference Proceedings (OSTI)

We report the most sensitive upper limit set on the mass of the electron antineutrino. The upper limit of 9.4 eV (95% confidence level) was obtained from a study of the shape of the beta decay spectrum of free molecular tritium. Achieving such a level of sensitivity required precise determinations of all processes that modify the shape of the observed spectrum. This result is in clear disagreement with a reported value for the mass of 26(5) eV. 30 refs., 3 figs., 2 tabs.

Wilkerson, J.F.; Bowles, T.J.; Friar, J.L.; Robertson, R.G.H.; Stephenson, G.J. Jr.; Wark, D.L. (Los Alamos National Lab., NM (USA)); Knapp, D.A. (Lawrence Livermore National Lab., CA (USA))

1990-01-01T23:59:59.000Z

99

Comparative tests of isospin-symmetry-breaking corrections to superallowed 0+-to-0+ nuclear beta decay  

E-Print Network (OSTI)

We present a test with which to evaluate the calculated isospin-symmetry-breaking corrections to superallowed 0+-to-0+ nuclear beta decay. The test is based on the corrected experimental Ft values being required to satisfy conservation of the vector current (CVC). When applied to six sets of published calculations, the test demonstrates quantitatively that only one set -- the one based on the shell model with Saxon-Woods radial wave functions -- provides satisfactory agreement with CVC. This test can easily be applied to any sets of calculated correction terms that are produced in future.

Towner, I S

2010-01-01T23:59:59.000Z

100

$\\beta$ Decay and Isomeric Properties of Neutron-Rich Ca and Sc Isotopes  

E-Print Network (OSTI)

The isomeric and $\\beta$-decay properties of neutron-rich $^{53-57}$Sc and $^{53,54}$Ca nuclei near neutron number $N$=32 are reported, and the low-energy level schemes of $^{53,54,56}$Sc and $^{53-57}$Ti are presented. The low-energy level structures of the $_{21}$Sc isotopes are discussed in terms of the coupling of the valence $1f_{7/2}$ proton to states in the corresponding $_{20}$Ca cores. Implications with respect to the robustness of the $N$=32 subshell closure are discussed, as well as the repercussions for a possible $N$=34 subshell closure.

Crawford, H L; Mantica, P F; Berryman, J S; Broda, R; Carpenter, M P; Cieplicka, N; Fornal, B; Grinyer, G F; Hoteling, N; Kay, B P; Lauritsen, T; Minamisono, K; Stefanescu, I; Stoker, J B; Walters, W B; Zhu, S

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Low-energy structure of 61Mn populated following $\\beta$ decay of 61Cr  

E-Print Network (OSTI)

$\\beta$ decay of the $^{61}$Cr$_{37}$ ground state has been studied. A new half-life of 233 +/- 11 ms has been deduced, and seven delayed $\\gamma$ rays have been assigned to the daughter, $^{61}$Mn$_{36}$. The low-energy level structure of $^{61}$Mn$_{36}$ is similar to that of the less neutron-rich $^{57,59}$Mn nuclei. The odd-A $_{25}$Mn isotopes follow the systematic trend in the yrast states of the even-even, Z + 1 $_{26}$Fe isotopes, and not that of the Z - 1 $_{24}$Cr isotopes, where a possible onset of collectivity has been suggested to occur already at N = 36.

Crawford, H L; Berryman, J S; Broda, R; Fornal, B; Hoffman, C R; Hoteling, N; Janssens, R V F; Lenzi, S M; Pereira, J; Stoker, J B; Tabor, S L; Walters, W B; Wang, X; Zhu, S

2009-01-01T23:59:59.000Z

102

Excitation functions of proton-induced reactions on natural Nd in the 10-30 MeV energy range, and production of radionuclides relevant for double-? decay  

E-Print Network (OSTI)

A preferred candidate for neutrinoless double-{\\beta} decay, 150Nd, is present in natural neodymium at an abundance level of 5.64%. However, neodymium could be activated by cosmic rays during the period it spends on the Earth's surface. Its activation by protons is therefore of interest when it comes to estimating the possible disturbance effects and increased background during neutrinoless double-{\\beta}-decay experiments like Sudbury Neutrino Observatory plus liquid scintillator (SNO+). In most cases, we lack experimental data on proton-induced reactions on neodymium. Therefore, a measurement of cross sections has been performed for the formation of 141Pm, 143Pm, 144Pm, 146Pm, 148Pm, 148Pmm, 149Pm, 150Pm, 140Nd, 141Nd, 147Nd, 149Nd, 138Prm, 139Pr, 142Pr, and 139Ce by 10-30 MeV protons. Oxidation-protected metal foil targets of natural isotopic abundance were irradiated by the usual stacked-foil technique on the external proton beam of the isochronous cyclotron U-120M at the Nuclear Physics Institute at \\v{R}e\\v{z} near Prague. Special attention was paid to the excitation functions of long-lived radionuclides. The measured data were compared with TENDL-2010 library data (TALYS code).

O. Lebeda; V. Lozza; P. Schrock; J. Štursa; K. Zuber

2012-02-23T23:59:59.000Z

103

Glossary Term - Beta Particle  

NLE Websites -- All DOE Office Websites (Extended Search)

Decay Previous Term (Beta Decay) Glossary Main Index Next Term (Bohr Radius) Bohr Radius Beta Particle Beta particles are either electrons or positrons ejected from the nucleus....

104

Inverse beta decay reaction in 232 Th and 233 U fission antineutrino flux  

E-Print Network (OSTI)

Energy spectra of antineutrinos coming from 232 Th and 233 U neutroninduced fission are calculated, relevant inverse beta decay ¯?e + p ? n+e + positron spectra and total cross sections are found. This study is stimulated by a hypothesis that a self-sustained nuclear chain reaction is burning at the center of the Earth (“Georeactor”). The Georeactor, according to the author of this idea, provides energy necessary to sustain the Earth’s magnetic field. The Georeactor’s nuclear fuel is 235 U and, probably, 232 Th and 233 U. Results of present study may appear to be useful in future experiments aimed to test the Georector hypothesis and to estimate its fuel components as a part of developments in geophysics and astrophysics based on observations of low energy antineutrinos in Nature.

G. Domogatski; V. Kopeikin; L. Mikaelyan; V. Sinev

2004-01-01T23:59:59.000Z

105

Deficit of reactor antineutrinos at distances smaller than 100 m and inverse beta-decay  

E-Print Network (OSTI)

We analyse a change of a deficit of reactor antineutrinos at distances smaller than 100 m by changing the lifetime of the neutron from tau_n = 885.7 s to tau_n = 879.6 s, calculated for the axial coupling constants lambda = - 1.2694 and lambda = - 1.2750, respectively, in order to get a result corresponding the new world average value tau_n = 880.1(1.1) s. We calculate the angular distribution and cross section for the inverse beta-decay, taking into account the contributions of the "weak magnetism" and the neutron recoil to next-to-leading order in the large baryon mass expansion and the radiative corrections of order alpha/\\pi ~ 10^(-3), calculated to leading order in the large baryon mass expansion. We obtain an increase of a deficit of reactor antineutrinos in of about 0.734%.

A. N. Ivanov; R. Hollwieser; N. I. Troitskaya; M. Wellenzohn; O. M. Zherebtsov; A. P. Serebrov

2013-06-09T23:59:59.000Z

106

Neutrinoless $??$ decay nuclear matrix elements in an isotopic chain  

E-Print Network (OSTI)

We analyze nuclear matrix elements (NME) of neutrinoless double beta decay calculated for the Cadmium isotopes. Energy density functional methods including beyond mean field effects such as symmetry restoration and shape mixing are used. Strong shell effects are found associated to the underlying nuclear structure of the initial and final nuclei. Furthermore, we show that NME for two-neutrino double beta decay evaluated in the closure approximation, $M^{2\

Tomás R. Rodríguez; Gabriel Martínez-Pinedo

2012-10-11T23:59:59.000Z

107

A Diffusion Cloud Chamber Study of Very Slow Mesons. II. Beta Decay of the Muon  

DOE R&D Accomplishments (OSTI)

The spectrum of electrons arising from the decay of the negative mu meson has been determined. The muons are arrested in the gas of a high pressure hydrogen filled diffusion cloud chamber. The momenta of the decay electrons are determined from their curvature in a magnetic field of 7750 gauss. The spectrum of 415 electrons has been analyzed according to the theory of Michel.

Lederman, L. M.; Sargent, C. P.; Rinehart, M.; Rogers, K.

1955-03-00T23:59:59.000Z

108

Low-energy structure of Co-66(27)39 and Co-68(27)41 populated through beta decay  

Science Conference Proceedings (OSTI)

The low-energy level structures for the neutron-rich Co isotopes at N = 39 and N = 41 are constructed following the beta decay of the respective even-even Fe isotopes. Spin and parity assignments of the lowest energy populated state in {sup 66}Co and {sup 68}Co are consistent with a 1{sup +} spin and parity assignment and attributed to the coupling of the deformed proton configurations identified in {sup 67}Co and deformed neutron configurations inferred from neighboring Fe isotones. Comparisons along the N = 39 and N = 41 isotonic chains reveal a similarity in the structures of the Co and Mn isotopes.

Liddick, S. N. [Michigan State University, East Lansing; Abromeit, B. [Michigan State University, East Lansing; Bolla, M [Michigan State University, East Lansing; Larson, N. [Michigan State University, East Lansing; Suchyta, S. [Michigan State University, East Lansing; Ayres, A [University of Tennessee, Knoxville (UTK); Bey, A. [University of Tennessee Medical Center, Knoxville; Bingham, C. R. [University of Tennessee, Knoxville (UTK); Cartegni, L. [University of Tennessee, Knoxville (UTK); Grzywacz, R. [University of Tennessee, Knoxville (UTK); Madurga, M [University of Tennessee, Knoxville (UTK); Miller, D [University of Tennessee, Knoxville (UTK); Padgett, Stephen [University of Tennessee, Knoxville (UTK); Paulauskas, S. [University of Tennessee, Knoxville (UTK); Crawford, H. L. [Lawrence Berkeley National Laboratory (LBNL); Darby, I. G. [Katholieke University Leuven, Belgium; Rajabali, M. M. [Katholieke University Leuven, Belgium; Ilyushkin, S. [Mississippi State University (MSU); Rykaczewski, Krzysztof Piotr [ORNL

2012-01-01T23:59:59.000Z

109

The Fermi And Gamov-Teller {beta}-Decay Excitations Of The Scissors Mode 1+ States  

Science Conference Proceedings (OSTI)

In this study, the allowed Gamov-Teller (GT) and Fermi {beta} transitions from 1+-state of the odd-odd nuclei to 1+-states are considered. Calculation of the {beta} transition matrix elements is performed in the phonon description and an analytical expressions for MF and MGT matrix elements are obtained for the first time.

Yildirm, Z.; Ertugral, F.; Kuliev, A. A. [Sakarya University, Physics Department, Adapazari (Turkey); Guliyev, E. [Institute of Physics, National Academy of Sciences, Baku (Azerbaijan)

2007-04-23T23:59:59.000Z

110

Weak reactions with light nuclei - 6He beta-decay as a test case for the nuclear weak current  

E-Print Network (OSTI)

We present a microscopic calculation of the 6He beta-decay into the ground state of 6Li. To this end we use the impulse approximation to describe the nuclear weak current. The ground state wave functions are obtained from the solution of the nuclear 6-body problem. The nucleonnucleon interaction is described via the J-matrix inverse scattering potential (JISP), and the nuclear problem is solved using the hyperspherical-harmonics approach. This approach results in numerical accuracy of about 2 per mil in the transition matrix element. Bearing in mind that the contribution of meson-exchange currents to the transition matrix element is about 5%, these results pave the way for accurate estimation of their effect.

Doron Gazit; Sergey Vaintraub; Nir Barnea

2009-01-18T23:59:59.000Z

111

Measurement of the Moments of the Hadronic Invariant Mass Distribution in Semileptonic Beta Decays  

SciTech Connect

Using 180 pb{sup -1} of data collected with the CDF II detector at the Tevatron, we measure the first two moments of the hadronic invariant mass-squared distribution in charmed semileptonic B decays. From these we determine the non-perturbative Heavy Quark Effective Theory parameters {Lambda} and {lambda}{sub 1} used to relate the B meson semileptonic branching ratio to the CKM matrix element |V{sub cb}|.

Acosta, D.; The CDF Collaboration TITLE=Measuremen

2005-03-13T23:59:59.000Z

112

Can Environmental Factors Affect Half-Life in Beta-Decay? An Analysis  

E-Print Network (OSTI)

Early in the history of the field of nuclear science, experiments were performed to ascertain whether the half-lives of the radioactive substances being studied – isotopes then called the “radium emanation” [222Rn], “radium A” [218Po], “radium B” [214Pb], and “radium C” [214Bi] - were dependent upon any external factors. At that time, the external factors deemed most likely to affect half-life were temperature and pressure. After several experiments, designed to pick up any change in half-life in the course of changing temperature or pressure, had failed to find any significant changes, it was concluded that half-life does not depend on the physical properties of external environment. And that was the state of the field for a long time - for almost 100 years, in fact. Fairly recently, however, half-life measurements were recorded, and published, that seemed to show a change in half-life at the few percent level for certain radioactive nuclides which were exposed to extremes of temperature - thus challenging the long-held belief in the unchangeability of half-lives. In addition to half-life changes caused by temperature change, other experiments seemed to find half-life changes caused by other external influences, including the chemical environment of the decaying radioactive nuclide, and even the distance between Earth and the Sun at the time of the half-life measurement. In this study we present evidence that the initial beliefs in the immutability of radioactive half-life (with the exception of a few nuclides decaying by electron capture whose orbital electrons are involved in both the decay and also in the chemical bonding of those nuclides) is indeed correct; we have done this by performing precise half-life measurements on the ?? emitter 198Au, the EC emitter 97Ru, and on the ?? emitter 198Au when sited in gold(III) oxide, Au2O3, (an insulator for practical purposes). We have performed various experiments designed to detect any half-life change at the level of a few parts in 10^4 due to change in temperature, physical environment, or the Earth-Sun distance. In these experiments, we have found no significant half-life change due to any of these external factors. These results represent the most accurate demonstrations of the immutability of radioactive half-life change ever made.

Goodwin, John 1953-

2012-12-01T23:59:59.000Z

113

Nuclear Shell Structure and Beta Decay I. Odd A Nuclei II. Even A Nuclei  

DOE R&D Accomplishments (OSTI)

In Part I a systematics is given of all transitions for odd A nuclei for which sufficiently reliable data are available. The allowed or forbidden characters of the transitions are correlated with the positions of the initial and final odd nucleon groups in the nuclear shell scheme. The nuclear shells show definite characteristics with respect to parity of the ground states. The latter is the same as the one obtained from known spins and magnetic moments in a one-particle interpretation. In Part II a systematics of the beta transitions of even-A nuclei is given. An interpretation of the character of the transitions in terms of nuclear shell structure is achieved on the hypothesis that the odd nucleon groups have the same structure as in odd-A nuclei, together with a simple coupling rule between the neutron and proton groups in odd-odd nuclei.

Mayer, M.G.; Moszkowski, S.A.; Nordheim, L.W.

1951-05-00T23:59:59.000Z

114

Search for bb decay with NEMO 3 and SuperNEMO experiments  

E-Print Network (OSTI)

NEMO 3 is a double beta decay experiment. A part of low background data was analysed, preliminary result on bb2nu decay of 130Te obtained: T_{1/2} = 7.6 \\+- 1.5(stat) +- 0.8(syst) * 10^{20} y$. No bb0nu signal was observed: T_{1/2}^{0\

V. Vasiliev; for the NEMO 3; SuperNEMO Collaborations

2007-10-26T23:59:59.000Z

115

DETERMINING THE RATIO OF THE H+ YIELDS TV TO H+ YIELDS TB DECAY RATES FOR LARGE TAN BETA AT THE LARGE HADRON COLLIDER.  

SciTech Connect

We present results on the determination of the observable ratio R = BR(H{sup +} {yields} {tau}{sup +}{nu}{sup -})/BR(H{sup +} {yields} t{bar b}) of charged Higgs boson decay rates as a discriminant quantity between Supersymmetric and non-Supersymmetric models. Simulation of measurements of this quantity through the analysis of the charged Higgs production process gb {yields} tbH{sup +} and relative backgrounds in the two above decay channels has been performed in the context of ATLAS. A {approx} 12-14% accuracy on R can be achieved for tan {beta} = 50, m{sub H{sup {+-}}} = 300-500 GeV and after an integrated luminosity of 300 fb{sup -1}. With this precision measurement, the Large Hadron Collider (LHC) can easily discriminate between models for the two above scenarios, so long as tan {beta} > 20.

ASSAMAGAN,K.A.GUASCH,J.MORETTI,S.PENARANDA,S.

2003-05-27T23:59:59.000Z

116

Collective and Non-Collective States in 116Cd Studied via the Beta-Decays of 116Agm1,m2,gs  

Science Conference Proceedings (OSTI)

We have re-investigated the beta decay of the three isomers of $^{116}$Ag at the Holifield Radioactive Ion Beam Facility (HRIBF). Through the use of half-life information, we have been able to construct individual decay schemes for each isomer, and correct what was a puzzling inconsistency with the published data, namely the beta feeding of 2$^+$ states by a 5$^+$ isomer. Our results indicate that the feeding of these levels arises from a 3$^+$ isomer in $^{116}$Ag. A total of 271 gamma-ray transitions (159 new) were assigned to 148 levels (94 new) from the beta-decay of $^{116m1,m2,gs}$Ag. Significant deviations are observed from expected U(5) symmetry in the 0$^+$ and 2$^+$ members of the previously assigned three-phonon quintuplet. Candidate states for the quadrupole-octupole quintuplet states and $\\pi$g$_{9/2}-\\pi$p$_{1/2}$, $\\pi$g$_{9/2}-\\pi$p$_{3/2}$, $\

Batchelder, Jon Charles [ORNL; Wood, John L [Georgia Institute of Technology; Garrett, Paul [University of Guelph; Rykaczewski, Krzysztof Piotr [ORNL; Bilheux, Jean-Christophe [ORNL; Bingham, Carrol R [ORNL; Carter, H Kennon [ORNL; Fong, Dennis [Vanderbilt University; Grzywacz, R. [University of Tennessee, Knoxville (UTK); Hamilton, Joseph [Vanderbilt University; Hartley, D J [U.S. Naval Academy; Hwang, J. K. [Vanderbilt University; Krolas, W [H. Niewodniczanski Institute of Nuclear Physics (INP), Krakow, Poland; Kulp, David [Georgia Institute of Technology; Larochelle, Y [University of Tennessee, Knoxville (UTK); Piechzczek, A [Louisiana State University; Ramayya, A. V. [Vanderbilt University; Spejewski, E.H. [Oak Ridge Associated Universities (ORAU); Stracener, Dan [Oak Ridge National Laboratory (ORNL); Tantawy, M.N. [University of Tennessee, Knoxville (UTK); Winger, J. A. [Mississippi State University (MSU); Zganjar, E. F. [Louisiana State University

2009-01-01T23:59:59.000Z

117

Proposed experiment to measure the neutron spin-electron angular correlation in polarized neutron beta decay with ultra-cold neutrons  

SciTech Connect

One area in which the Standard Model can be probed is neutron beta decay. In particular, measurements of angular correlations in neutron beta decay can place constraints on the existence of right-handed currents, the presence of scalar and tensor terms in the weak interaction, and for evidence of Time Reversal Violation, which is expected from the observed violation of CP invariance in kaon decay. A measurement of A, the correlation between the neutron spin and the direction of emission of the electron in neutron decay, can be combined with the neutron lifetime to determine the fundamental vector and axial vector weak coupling constants G{sub A} and G{sub V}. The authors have presented the essential elements of their plans to carry out an A correlation measurement using the UCN source they have constructed at the Manuel Lujan Neutron Scattering Center (MLNSC). Their goal is an initial measurement with an accuracy of about 0.2% of A (which has a value of about {minus}0.114). The count rate expected in the experiment will allow a determination at this statistical accuracy level in a running time of about four months.

Seestrom, S.J.; UCN A Collaboration

1998-12-01T23:59:59.000Z

118

Measurement of the electron antineutrino mass in tritium beta decay in the Troitsk nu-mass experiment  

SciTech Connect

The results obtained in the Troitsk nu-mass experiment by measuring the electron-antineutrino mass in tritium beta decay are presented. The facility used consists of a gaseous windowless tritium source and an electrostatic electron spectrometer involving an adiabatic magnetic collimation. Runs in which measurement conditions were reliably established were thoroughly selected in analyzing data obtained from 1994 to 2004. All known systematic effects were taken into account. For the square of the electron-antineutrino mass, the treatment of measured spectra yielded the following result: m{sub {nu}}{sup 2} = -0.67 {+-} 1.89{sub stat.} {+-} 1.68{sub syst.} eV{sup 2}. The use of the Bayesian method and the Feldman-Cousins unified approach made it possible to obtain the following upper limits on the mass: m{sub {nu}} < 2.12 eV (at a 95% C.L.; Bayesian method) and m{sub {nu}} < 2.05 eV (at a 95% C.L., Feldman-Cousins method). At the same time, an estimation of the sensitivity limit without allowance for negative values of the square of the mass leads to m{sub {nu}} < 2.2 eV (at a 95% C.L.). Measured spectra were analyzed for the possible existence of an additional structure (step) in the electron spectrum near the boundary energy. The conclusion drawn from this analysis was that, within the existing statistical errors, there are no reasons for introducing such a feature.

Aseev, V. N.; Belesev, A. I.; Berlev, A. I.; Geraskin, E. V.; Golubev, A. A.; Lihovid, N. A.; Lobashev, V. M.; Nozik, A. A.; Pantuev, V. S.; Parfenov, V. I.; Skasyrskaya, A. K.; Tkachov, F. V.; Zadorozhny, S. V. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

2012-04-15T23:59:59.000Z

119

Structure of 65,67Co studied through the beta decay of 65,67Fe and a deep-inelastic reaction  

E-Print Network (OSTI)

The neutron-rich isotopes 65,67Fe and 65Co have been produced at the LISOL facility, Louvain-La-Neuve, in the proton-induced fission of 238U. Beams of these isotopes have been extracted with high selectivity by means of resonant laser ionization combined with mass separation. Yrast and near-yrast levels of 65Co have also been populated in the 64Ni+238U reaction at Argonne National Laboratory. The level structure of 65Co could be investigated by combining all the information from both the 65Fe and 65Co beta decay and the deep-inelastic reaction. The 65Fe, 65Co and 67Fe decay schemes and the 65Co yrast structure are fully established. The 65,67Co level structures can be interpreted as resulting from the coexistence of core-coupled states with levels based on a low-energy proton-intruder configuration.

Pauwels, D; Bree, N; Buscher, J; Cocolios, T E; Huyse, M; Kudryavtsev, Yu; Raabe, R; Sawicka, M; Van de Walle, J; Van Duppen, P; Korgul, A; Stefanescu, I; Hecht, A A; Hoteling, N; Wöhr, A; Walters, W B; Broda, R; Fornal, B; Krolas, W; Pawlat, T; Wrzesinski, J; Carpenter, M P; Janssens, R V F; Lauritsen, T; Seweryniak, D; Zhu, S; Stone, J R; Wang, X

2009-01-01T23:59:59.000Z

120

Structure of 65,67Co studied through the beta decay of 65,67Fe and a deep-inelastic reaction  

E-Print Network (OSTI)

The neutron-rich isotopes 65,67Fe and 65Co have been produced at the LISOL facility, Louvain-La-Neuve, in the proton-induced fission of 238U. Beams of these isotopes have been extracted with high selectivity by means of resonant laser ionization combined with mass separation. Yrast and near-yrast levels of 65Co have also been populated in the 64Ni+238U reaction at Argonne National Laboratory. The level structure of 65Co could be investigated by combining all the information from both the 65Fe and 65Co beta decay and the deep-inelastic reaction. The 65Fe, 65Co and 67Fe decay schemes and the 65Co yrast structure are fully established. The 65,67Co level structures can be interpreted as resulting from the coexistence of core-coupled states with levels based on a low-energy proton-intruder configuration.

D. Pauwels; O. Ivanov; N. Bree; J. Buscher; T. E. Cocolios; M. Huyse; Yu. Kudryavtsev; R. Raabe; M. Sawicka; J. Van de Walle; P. Van Duppen; A. Korgul; I. Stefanescu; A. A. Hecht; N. Hoteling; A. Wohr; W. B. Walters; R. Broda; B. Fornal; W. Krolas; T. Pawlat; J. Wrzesinski; M. P. Carpenter; R. V. F. Janssens; T. Lauritsen; D. Seweryniak; S. Zhu; J. R. Stone; X. Wang

2009-03-09T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Lepton flavour violating Higgs Boson decays, tau --> mu gamma and B(s) --> mu+mu- in the constrained MSSM+NR with large tan beta  

E-Print Network (OSTI)

Realistic predictions are made for the rates of lepton flavour violating Higgs boson decays, tau --> mu gamma, mu --> e gamma, Bs --> mu+mu-, Bs --> tau mu and tau --> 3mu, via a top-down analysis of the Minimal Supersymmetric Standard Model(MSSM) constrained by SU(5) unification with right-handed Neutrinos and large tan beta. The third family neutrino Yukawa coupling is chosen to be of order 1, in this way our model bares a significant resemblance to supersymmetric SO(10). In this framework the large PMNS mixings result in potentially large lepton flavour violation. Our analysis predicts tau --> mu gamma and mu --> e gamma rates in the region (10^{-8}-10^{-6}) and (10^{-15}-10^{-14}) respectively. We also show that the rates for lepton flavour violating Higgs decays can be as large as 10^{-7}. The non-decoupling nature of H --> tau mu is observed which leads to its decay rate becoming comparable to that for tau --> mu gamma for large values of m_0 and M_1/2. We also find that the present bound on Bs --> mu+mu- is an important constraint on the rate of lepton flavour violating Higgs decays. The recently measured Bs-Bsbar mixing parameter Delta Ms is also investigated.

J. K. Parry

2005-10-24T23:59:59.000Z

122

The possible test of the calculations of nuclear matrix elements of the $(??)_{0?}$-decay  

E-Print Network (OSTI)

The existing calculations of the nuclear matrix elements of the neutrinoless double $\\beta$-decay differ by about a factor three. This uncertainty prevents quantitative interpretation of the results of experiments searching for this process. We suggest here that the observation of the neutrinoless double $\\beta$-decay of {\\em several} nuclei could allow to test calculations of the nuclear matrix elements through the comparison of the ratios of the calculated lifetimes with experimental data. It is shown that the ratio of the lifetimes is very sensitive to different models.

S. M. Bilenky; J. A. Grifols

2002-11-07T23:59:59.000Z

123

A measurement of the 2 neutrino double beta decay rate of Te-130 in the CUORICINO experiment  

E-Print Network (OSTI)

large BF 3 counters, Nuovo Cim. A (1971-1996), 101, 959 (Sasso Laboratory, Nuovo Cim. , A112, 819 (1999). [91] H.physics, Riv. Nuovo Cim. (1978-1999), 9, 1 (1986). [95

Kogler, Laura

2012-01-01T23:59:59.000Z

124

A measurement of the 2 neutrino double beta decay rate of 130Te in the CUORICINO experiment  

E-Print Network (OSTI)

large BF 3 counters, Nuovo Cim. A (1971-1996), 101, 959 (Sasso Laboratory, Nuovo Cim. , A112, 819 (1999). [91] H.physics, Riv. Nuovo Cim. (1978-1999), 9, 1 (1986). [95

Kogler, Laura Katherine

2011-01-01T23:59:59.000Z

125

Measurement of the Double-Beta Decay Half-life of 136Xe in KamLAND-Zen  

E-Print Network (OSTI)

with con- tamination by fallout from the Fukushima-I reactormaterials by Fukushima fallout, which include 110m Ag. OnePo- tential backgrounds from fallout nuclei with half-lives

Gando, A.

2013-01-01T23:59:59.000Z

126

A measurement of the 2 neutrino double beta decay rate of 130Te in the CUORICINO experiment  

E-Print Network (OSTI)

a temperature sensor, and a weak thermal link connecting thedissipated through the weak thermal link, the temperature of

Kogler, Laura Katherine

2011-01-01T23:59:59.000Z

127

A measurement of the 2 neutrino double beta decay rate of Te-130 in the CUORICINO experiment  

E-Print Network (OSTI)

a temperature sensor, and a weak thermal link connecting thedissipated through the weak thermal link, the temperature of

Kogler, Laura

2012-01-01T23:59:59.000Z

128

Measurement of the Double-Beta Decay Half-life of 136Xe in KamLAND-Zen  

E-Print Network (OSTI)

by fallout from the Fukushima-I reactor accident in Marchof detector materials by Fukushima fallout, which includeCo are not detected near Fukushima or our soil samples, we

Gando, A.

2013-01-01T23:59:59.000Z

129

Search for the second forbidden {beta} decay of {sup 8}B to the ground state of {sup 8}Be  

Science Conference Proceedings (OSTI)

A significant decay branch of {sup 8}B to the ground state of {sup 8}Be would extend the solar neutrino spectrum to higher energies than anticipated in the standard solar models. These high-energy neutrinos would affect current neutrino oscillation results and also would be a background to measurements of the hep process. We have measured the delayed {alpha} particles from the decay of {sup 8}B, with the goal of observing the two 46-keV {alpha} particles arising from the ground-state decay. The {sup 8}B was produced using an in-flight radioactive beam technique. It was implanted in a silicon PIN-diode detector that was capable of identifying the {alpha} particles from the {sup 8}Be ground state. From this measurement we find an upper limit (at 90% confidence level) of 7.3x10{sup -5} for the branching ratio to the ground state. In addition to describing this measurement, we present a theoretical calculation for this branching ratio.

Bacrania, M. K.; Boyd, N. M.; Robertson, R. G. H.; Storm, D. W. [Center for Experimental Nuclear Physics and Astrophysics, Physics Department, University of Washington, Seattle, Washington 98195 (United States)

2007-11-15T23:59:59.000Z

130

Search for the second forbidden beta decay of 8B to the ground state of 8Be  

E-Print Network (OSTI)

A significant decay branch of 8B to the ground state of 8Be would extend the solar neutrino spectrum to higher energies than anticipated in the standard solar models. These high-energy neutrinos would affect current neutrino oscillation results and also would be a background to measurements of the hep process. We have measured the delayed alpha particles from the decay of 8B, with the goal of observing the two 46-keV alpha particles arising from the ground-state decay. The 8B was produced using an in-flight radioactive beam technique. It was implanted in a silicon PIN-diode detector that was capable of identifying the alpha-particles from the 8Be ground state. From this measurement we find an upper limit (at 90% confidence level) of 7.3 x 10^{-5} for the branching ratio to the ground state. In addition to describing this measurement, we present a theoretical calculation for this branching ratio.

M. K. Bacrania; N. M. Boyd; R. G. H. Robertson; D. W. Storm

2007-10-28T23:59:59.000Z

131

Search for the second forbidden beta decay of 8B to the ground state of 8Be  

E-Print Network (OSTI)

A significant decay branch of 8B to the ground state of 8Be would extend the solar neutrino spectrum to higher energies than anticipated in the standard solar models. These high-energy neutrinos would affect current neutrino oscillation results and also would be a background to measurements of the hep process. We have measured the delayed alpha particles from the decay of 8B, with the goal of observing the two 46-keV alpha particles arising from the ground-state decay. The 8B was produced using an in-flight radioactive beam technique. It was implanted in a silicon PIN-diode detector that was capable of identifying the alpha-particles from the 8Be ground state. From this measurement we find an upper limit (at 90% confidence level) of 7.3 x 10^{-5} for the branching ratio to the ground state. In addition to describing this measurement, we present a theoretical calculation for this branching ratio.

Bacrania, M K; Robertson, R G H; Storm, D W

2007-01-01T23:59:59.000Z

132

The GERDA experiment for the search of 0??? decay in ^{76}Ge  

E-Print Network (OSTI)

The GERDA collaboration is performing a search for neutrinoless double beta decay of ^{76}Ge with the eponymous detector. The experiment has been installed and commissioned at the Laboratori Nazionali del Gran Sasso and has started operation in November 2011. The design, construction and first operational results are described, along with detailed information from the R&D phase.

GERDA Collaboration; K. -H. Ackermann; M. Agostini; M. Allardt; M. Altmann; E. Andreotti; A. M. Bakalyarov; M. Balata; I. Barabanov; M. Barnabe Heider; N. Barros; L. Baudis; C. Bauer; N. Becerici-Schmidt; E. Bellotti; S. Belogurov; S. T. Belyaev; G. Benato; A. Bettini; L. Bezrukov; T. Bode; V. Brudanin; R. Brugnera; D. Budjas; A. Caldwell; C. Cattadori; A. Chernogorov; O. Chkvorets; F. Cossavella; A. D`Andragora; E. V. Demidova; A. Denisov; A. di Vacri; A. Domula; V. Egorov; R. Falkenstein; A. Ferella; K. Freund; F. Froborg; N. Frodyma; A. Gangapshev; A. Garfagnini; J. Gasparro; S. Gazzana; R. Gonzalez de Orduna; P. Grabmayr; V. Gurentsov; K. Gusev; K. K. Guthikonda; W. Hampel; A. Hegai; M. Heisel; S. Hemmer; G. Heusser; W. Hofmann; M. Hult; L. V. Inzhechik; L. Ioannucci; J. Janicsko Csalty; J. Jochum; M. Junker; R. Kankanyan; S. Kianovsky; T. Kihm; J. Kiko; I. V. Kirpichnikov; A. Kirsch; A. Klimenko; M. Knapp; K. T. Knöpfle; O. Kochetov; V. N. Kornoukhov; K. Kröninger; V. Kusminov; M. Laubenstein; A. Lazzaro; V. I. Lebedev; B. Lehnert; D. Lenz; H. Liao; M. Lindner; I. Lippi; J. Liu; X. Liu; A. Lubashevskiy; B. Lubsandorzhiev; A. A. Machado; B. Majorovits; W. Maneschg; G. Marissens; S. Mayer; G. Meierhofer; I. Nemchenok; L. Niedermeier; S. Nisi; J. Oehm; C. O'Shaughnessy; L. Pandola; P. Peiffer; K. Pelczar; A. Pullia; S. Riboldi; F. Ritter; C. Rossi Alvarez; C. Sada; M. Salathe; C. Schmitt; S. Schönert; J. Schreiner; J. Schubert; O. Schulz; U. Schwan; B. Schwingenheuer; H. Seitz; E. Shevchik; M. Shirchenko; H. Simgen; A. Smolnikov; L. Stanco; F. Stelzer; H. Strecker; M. Tarka; U. Trunk; C. A. Ur; A. A. Vasenko; S. Vogt; O. Volynets; K. von Sturm; V. Wagner; M. Walter; A. Wegmann; M. Wojcik; E. Yanovich; P. Zavarise; I. Zhitnikov; S. V. Zhukov; D. Zinatulina; K. Zuber; G. Zuzel

2012-12-17T23:59:59.000Z

133

Reexamining the Beta Decay of 53,54Ni, 52,53Co, 51Fe, and 50Mn  

Science Conference Proceedings (OSTI)

he decay of 53,54Ni, 52,53Co, 51Fe, and 50Mn was investigated via the fragmentation of a 58Ni primary beam with an energy of 68.6 MeV/u. The proton- coincidences of 53Ni -delayed proton emission were observed. Based on the analysis of the proton- coincidence events, it was inferred that the previous assignment of the excitation energy for the isobaric analog state in 53Co may be problematic. The half-lives of these nuclei were obtained, in which the uncertainty of 52Co half-life was reduced by a factor of 3. The half-lives were evaluated and used as inputs of nucleosynthesis calculations of the rapid proton-capture process in an x-ray burst.

Su, J. [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing, China; Liu, W. P. [China Institute of Atomic Energy Collaboration; Collaboration, [China Institute of Atomic Energy Collaboration; Wang, J. S. [Inst. Modern Phys., Chinese Academy of Sciences-Lanzhou; Collaboration, [Inst. Modern Phys., Chinese Academy of Sciences-Lanzhou; Li, X. Q. [Peking University-Beijing; He, C. [Peking University-Beijing; Smith, Michael Scott [ORNL

2013-01-01T23:59:59.000Z

134

Superallowed 0{sup +}{yields}0{sup +} nuclear {beta} decays: A new survey with precision tests of the conserved vector current hypothesis and the standard model  

Science Conference Proceedings (OSTI)

A new critical survey is presented of all half-life, decay-energy, and branching-ratio measurements related to 20 superallowed 0{sup +}{yields}0{sup +}{beta} decays. Compared with our last review, there are numerous improvements: First, we have added 27 recently published measurements and eliminated 9 references, either because they have been superseded by much more precise modern results or because there are now reasons to consider them fatally flawed; of particular importance, the new data include a number of high-precision Penning-trap measurements of decay energies. Second, we have used the recently improved isospin symmetry-breaking corrections, which were motivated by these new Penning-trap results. Third, our calculation of the statistical rate function f now accounts for possible excitation in the daughter atom, a small effect but one that merits inclusion at the present level of experimental precision. Finally, we have re-examined the systematic uncertainty associated with the isospin symmetry-breaking corrections by evaluating the radial-overlap correction using Hartree-Fock radial wave functions and comparing the results with our earlier calculations, which used Saxon-Woods wave functions; the provision for systematic uncertainty has been changed as a consequence. The new ''corrected''Ft values are impressively constant and their average, when combined with the muon lifetime, yields the up-down quark-mixing element of the Cabibbo-Kobayashi-Maskawa (CKM) matrix, V{sub ud}=0.97425{+-}0.00022. The unitarity test on the top row of the matrix becomes |V{sub ud}|{sup 2}+|V{sub us}|{sup 2}+|V{sub ub}|{sup 2}=0.99995{+-}0.00061. Both V{sub ud} and the unitarity sum have significantly reduced uncertainties compared with our previous survey, although the new value of V{sub ud} is statistically consistent with the old one. From these data we also set limits on the possible existence of scalar interactions, right-hand currents, and extra Z bosons. Finally, we discuss the priorities for future theoretical and experimental work with the goal of making the CKM unitarity test even more definitive.

Hardy, J. C.; Towner, I. S. [Cyclotron Institute, Texas A and M University, College Station, Texas 77843 (United States)

2009-05-15T23:59:59.000Z

135

Relation between the 2{nu}{beta}{beta} and 0{nu}{beta}{beta} nuclear matrix elements  

SciTech Connect

A formal relation between the GT part of the nuclear matrix elements M{sub GT}{sup 0{nu}} of 0{nu}{beta}{beta} decay and the closure matrix elements M{sub cl}{sup 2{nu}} of 2{nu}{beta}{beta} decay is established. This relation is based on the integral representation of these quantities in terms of their dependence on the distance r between the two nucleons undergoing transformation. We also discuss the difficulties in determining the correct values of the closure 2{nu}{beta}{beta} decay matrix elements.

Vogel, Petr [Kellogg Radiation Laboratory, Caltech, Pasadena, CA 91125 (United States); Simkovic, Fedor [Department of Nuclear Physics and Biophysics, Comenius University, Mlynska dolina F1, SK-84248 Bratislava (Slovakia)

2011-12-16T23:59:59.000Z

136

Optical studies of the {beta}{double_prime}-(ET){sub 2}SF{sub 5}RSO{sub 3} R = CH{sub 2}CF{sub 2}, CHFCF{sub 2} and CHF system: Chemical tuning of the counterion  

SciTech Connect

The authors compare the polarized optical spectra of the organic metal {beta}{double_prime}-(ET){sub 2}SF{sub 5}CHFSO{sub 3} and the {beta}{double_prime}-ET{sub 2}SF{sub 5}CHFCF{sub 2}SO{sub 3} metal/insulator material with those of the first fully organic superconductor {beta}{double_prime}-ET{sub 2}SF{sub 5}CH{sub 2}SO{sub 3}. The small chemical modification of the counterion has a dramatic effect on the spectral and charge transport properties of these materials, and they discuss their electronic structure in terms of band structure, many-body effects, and disorder. Based on structural differences in the anion pocket of the three salts, they conclude that the unusual electronic excitations observed in the {beta}{double_prime}-(ET){sub 2}SF{sub 5}CHFCF{sub 2}SO{sub 3} metal/insulator material are caused by disorder-related localization.

Olejniczak, I.; Jones, B. R.; Dong, J.; Pigos, J. M.; Zhu, Z.; Garlach, A. D.; Musfeldt, J. L.; Koo, H.-J.; Whangbo, M.-H.; Schlueter, J. A.; Ward, B. H.; Morales, E.; Kini, A. M.; Winter, R. W.; Mohtasham, J.; Gard, G. L.

2000-07-24T23:59:59.000Z

137

Distribution of ranks of ?-decay half-lives  

E-Print Network (OSTI)

I studied the distribution of ranks of values of 2949 {\\beta}-decay half-lives according to an empirical beta law with two exponents. {\\beta}-decay half-life ranks showed good fit to a beta function with two exponents.

Juan Miguel Campanario

2010-11-21T23:59:59.000Z

138

Semileptonic Decays  

SciTech Connect

The following is an overview of the measurements of the CKM matrix elements |V{sub cb}| and |V{sub ub}| that are based on detailed studies of semileptonic B decays by the BABAR and Belle Collaborations and major advances in QCD calculations. In addition, a new and improved measurement of the ratios R(D{sup (*)}) = {Beta}({bar B} {yields} D{sup (*)}{tau}{sup -}{bar {nu}}{sub {tau}})/{Beta}({bar B} {yields} D{sup (*)}{ell}{sup -}{bar {nu}}{sub {ell}}) is presented. Here D{sup (*)} refers to a D or a D* meson and {ell} is either e or {mu}. The results, R(D) = 0.440 {+-} 0.058 {+-} 0.042 and R(D*) = 0.332 {+-} 0.024 {+-} 0.018, exceed the Standard Model expectations by 2.0{sigma} and 2.7{sigma}, respectively. Taken together, they disagree with these expectations at the 3.4{sigma} level. The excess of events cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.

Luth, Vera G.; /SLAC

2012-10-02T23:59:59.000Z

139

Future prospects of baryon istability search in p-decay and n n(bar) oscillation experiments  

Science Conference Proceedings (OSTI)

These proceedings contain thirty-one papers which review both the theoretical and the experimental status and near future of baryon instability research. Baryon instability is investigated from the vantage point of supersymmetric and unified theories. The interplay between baryogenesis and antimatter is examined. Double beta decay experiments are discussed. The huge Icarus experiment is described with its proton decay capabilities. Neutron-antineutron oscillations investigations are presented, especially efforts with ultra-cold neutrons. Individual papers are indexed separately on the Energy Data Base.

Ball, S.J.; Kamyshkov, Y.A. [ed.

1996-11-01T23:59:59.000Z

140

Using NERSC Systems, Physcists Close in on a Rare-Particle Decay Process  

NLE Websites -- All DOE Office Websites (Extended Search)

Using NERSC Systems, Using NERSC Systems, Physcists Close in on a Rare-Particle Decay Process Using NERSC Systems, Physicists Close In on a Rare-Particle Decay Process Underground Experiment May Unlock the Mysteries of the Neutrino June 11, 2012 | Tags: Accelerator Science, High Energy Physics (HEP), Hopper NERSC Contact: Linda Vu, lvu@lbl.gov, +1 510 495 2402 exo-1.jpg Located at the Waste Isolation Pilot Plant near Carlsbad, New Mexico, EXO-200 is a 200-kg detector using liquid xenon, enriched in the isotope 136, to detect "neutrino-less double beta decay." With help from supercomputers at the Department of Energy's National Energy Research Scientific Computing Center (NERSC), the Enriched Xenon Observatory experiment (EXO-200) has placed the most stringent constraints

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While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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141

Simultaneous beta and gamma spectroscopy  

DOE Patents (OSTI)

A phoswich radiation detector for simultaneous spectroscopy of beta rays and gamma rays includes three scintillators with different decay time characteristics. Two of the three scintillators are used for beta detection and the third scintillator is used for gamma detection. A pulse induced by an interaction of radiation with the detector is digitally analyzed to classify the type of event as beta, gamma, or unknown. A pulse is classified as a beta event if the pulse originated from just the first scintillator alone or from just the first and the second scintillator. A pulse from just the third scintillator is recorded as gamma event. Other pulses are rejected as unknown events.

Farsoni, Abdollah T. (Corvallis, OR); Hamby, David M. (Corvallis, OR)

2010-03-23T23:59:59.000Z

142

B Decay  

NLE Websites -- All DOE Office Websites (Extended Search)

Decay Decay B mesons are short-lived and decay inside the beam pipe, which is about 2.5 cm (1 inch) in diameter. Physicists project the tracks seen in the detector elements outside the beampipe back to where the particles must have traveled inside the beam pipe. We call a point where particles collide or decay a vertex. A way to identify a B meson is to look for two vertices with a gap between them. On the left is a standard event picture. On the right is a blowup of what happens close to the collision point inside the beam pipe. The vertex is where the B meson along with other particles was created and the secondary vertex is where it decayed. The solid green lines are the actual tracks of the decay particles outside the beam pipe. The dotted lines are the projection of the tracks into the beam pipe. Where they intersect are the vertices. The B travels between the first vertex and the secondary vertex along the black dotted line before it decays. Thus, the gap between the two vertices is a measure of the lifetime of the B meson. We will be looking for this decay length in our data. We will find a minimum or "threshold" value that will tell us to save events for further analysis.

143

Beta Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Beta Radiation 1. Beta radiation may travel meters in air and is moderately penetrating. 2. Beta radiation can penetrate human skin to the "germinal layer," where new skin cells...

144

Energy density functional study of nuclear matrix elements for neutrinoless $??$ decay  

E-Print Network (OSTI)

We present an extensive study of nuclear matrix elements (NME) for the neutrinoless double beta decay of the nuclei $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{116}$Cd, $^{124}$Sn, $^{128}$Te, $^{130}$Te, $^{136}$Xe, and $^{150}$Nd based on state-of-the-art energy density functional methods using the Gogny D1S functional. Beyond mean-field effects are included within the generating coordinate method with particle number and angular momentum projection for both initial and final ground states. We obtain a rather constant value for the NME's around 4.7 with the exception of $^{48}$Ca and $^{150}$Nd, where smaller values are found. We analyze the role of deformation and pairing in the evaluation of the NME and present detailed results for the decay of $^{150}$Nd.

Tomás R. Rodríguez; G. Martinez-Pinedo

2010-08-31T23:59:59.000Z

145

Nuclear matrix elements of exotic 0{nu}{beta}{beta}-mechanisms  

SciTech Connect

An uncontroversial detection of the 0{nu}{beta}{beta}-decay will prove the total lepton number to be broken in nature, and neutrinos to be Majorana particles. However, it will immediately generate questions: What is the mechanism that triggers the decay? What happens if several mechanisms are active for the decay? There is a general consensus that a measurement of the 0{nu}{beta}{beta}-decay in one isotope does not allow us to determine the underlying physics mechanism. Complementary measurements in different isotopes is very important. It is thus important that experiments involving as many different targets as possible to be pursued. Furthermore, in the presence of interference between the various mechanisms, the availability of reliable nuclear matrix elements becomes more imperative.

Simkovic, Fedor [Laboratory of Theoretical Physics, JINR, 141980 Dubna, Moscow region (Russian Federation)

2011-12-16T23:59:59.000Z

146

Glossary Term - Alpha Decay  

NLE Websites -- All DOE Office Websites (Extended Search)

Universe Previous Term (10 Most Abundant Elements in the Universe) Glossary Main Index Next Term (Alpha Particle) Alpha Particle Alpha Decay Alpha Decay Diagram Alpha decay is one...

147

Random coincidence of $2\  

E-Print Network (OSTI)

Two neutrino double $\\beta$ decay can create irremovable background even in high energy resolution detectors searching for neutrinoless double $\\beta$ decay due to random coincidence of $2\

D. M. Chernyak; F. A. Danevich; A. Giuliani; E. Olivieri; M. Tenconi; V. I. Tretyak

2013-01-17T23:59:59.000Z

148

D meson hadronic decays at CLEO-c  

SciTech Connect

The recent CLEO-c results on hadronic decays of D and D{sub s} mesons are presented. First the absolute branching fractions for D and D{sub s} mesons using a double tag technique are discussed, then are the Cabibbo suppressed decays and doubly Cabibbo suppressed decays. Finally, I present the inclusive and rare decay modes and other measurements from CLEO-c. These decays illuminate a wide range of physics. A brief theoretical introduction is given before the corresponding discussion on measurement.

Yang, Fan; /Fermilab

2011-01-01T23:59:59.000Z

149

Searches for Leptonic B Decays at BaBar  

SciTech Connect

Measurements of the branching fractions of purely leptonic decays of B-mesons translate into constraints in the plane of the charged Higgs mass versus tan {beta} which are relatively insensitive to the particular theoretical model. Using the full BABAR dataset of 450 million B-decays we search for these decays. No significant signal is found in the decays into electrons or muons and we set upper limits on the branching fractions of the order of a 10{sup -6} at 90% confidence level. We measure the branching fraction of B {yields} {tau}{mu} to be (1.7 {+-} 0.6) x 10{sup -4}.

Nelson, Silke; /SLAC

2012-04-25T23:59:59.000Z

150

Bounds on Heavy-to-Heavy Weak Decay Form Factors  

E-Print Network (OSTI)

We provide upper and lower bounds on the semileptonic weak decay form factors for $B \\to D^(*)$ and $\\Lambda_b \\to \\Lambda_c$ decays by utilizing inclusive heavy quark effective theory sum rules. These bounds are calculated to second order in $\\Lambda_{QCD}/m_Q$ and first order in $\\alpha_s$. The $O(\\alpha_s^2 \\beta_0)$ corrections to the bounds at zero recoil are also presented.

Chiang, C W

2001-01-01T23:59:59.000Z

151

Bounds on Heavy-to-Heavy Weak Decay Form Factors  

E-Print Network (OSTI)

We provide upper and lower bounds on the semileptonic weak decay form factors for $B \\to D^(*)$ and $\\Lambda_b \\to \\Lambda_c$ decays by utilizing inclusive heavy quark effective theory sum rules. These bounds are calculated to second order in $\\Lambda_{QCD}/m_Q$ and first order in $\\alpha_s$. The $O(\\alpha_s^2 \\beta_0)$ corrections to the bounds at zero recoil are also presented.

Cheng-Wei Chiang

2000-09-18T23:59:59.000Z

152

The central bond sup 13 C double bond sup 13 C isotope effect for superconductivity in the high-T sub c. beta. *-(ET) sub 2 I sub 3 phase and its implications regarding the superconducting pairing mechanism in TTF-based organic superconductors  

Science Conference Proceedings (OSTI)

We report a new study, based on magnetization measurements, of the isotope effect for {sup 13}C substitution in the electronically active central double-bonded carbon atoms (C=C) of the TTF moiety of ET (bis(ethylenedithio)tetrathiafulvalene) in {beta}*-(ET){sub 2}I{sub 3} which is the crystallographically ordered form of {beta}-(ET){sub 2}I{sub 3} produced by application of pressure. A recent report by Merzhanov et al. (C. R. Acad. Sci., Paris, 314, 563 (1992)) has shown that this same {sup C} substitution leads to a giant'' isotope effect ({Delta}{Tc} = {minus} 0.6 K) in resistive determinations of {Tc} ({approximately} 8 K) for {beta}-(ET){sub 2}I{sub 3}, which lends experimental support to a theory by Yamaji (Solid State Common., 61, 413. (1987)) for salts of TTF-analogue donor molecules that includes optical phonons of symmetric intramolecular vibrations as a source of mediation for superconducting pairing of charge-carriers. In contrast to this result, our study shows the absence of an isotope effect within a precision of {plus minus} 0.1 K.({approximately} l%), indicating that the central atom C=C stretching motion ({approximately} 1500 cm{sup {minus}1}) of ET cannot be a dominant mechanism for phonon exchange. Our results are consistent with those of a very recent study of the same isotope effect for {kappa}-(ET){sub 2}Cu(N(CN){sub 2})Br and {kappa}-(ET){sub 2}Cu(NCS){sub 2} (Inorg. Chem., 32, 3356 (1992)).

Carlson, K.D.; Williams, J.M.; Geiser, U.; Kini, A.M.; Wang, H.H.; Klemm, R.A.; Kumar, S.K.; Schlueter, J.A.; Ferraro, J.R.; Lykke, K.R.; Wurz, P.; Sutin, J.D.B. (Argonne National Lab., IL (United States)); Parker, D.H. (Argonne National Lab., IL (United States) California Univ., Irvine, CA (United States). Dept. of Chemistry); Schirber, J.E.; Venturini, E.L. (Sandia National Labs., Albuquerque, NM (United S

1992-01-01T23:59:59.000Z

153

The central bond {sup 13}C{double_bond}{sup 13}C isotope effect for superconductivity in the high-T{sub c} {beta}*-(ET){sub 2}I{sub 3} phase and its implications regarding the superconducting pairing mechanism in TTF-based organic superconductors  

SciTech Connect

We report a new study, based on magnetization measurements, of the isotope effect for {sup 13}C substitution in the electronically active central double-bonded carbon atoms (C=C) of the TTF moiety of ET [bis(ethylenedithio)tetrathiafulvalene] in {beta}*-(ET){sub 2}I{sub 3} which is the crystallographically ordered form of {beta}-(ET){sub 2}I{sub 3} produced by application of pressure. A recent report by Merzhanov et al. [C. R. Acad. Sci., Paris, 314, 563 (1992)] has shown that this same {sup C} substitution leads to a ``giant`` isotope effect ({Delta}{Tc} = {minus} 0.6 K) in resistive determinations of {Tc} ({approximately} 8 K) for {beta}-(ET){sub 2}I{sub 3}, which lends experimental support to a theory by Yamaji [Solid State Common., 61, 413. (1987)] for salts of TTF-analogue donor molecules that includes optical phonons of symmetric intramolecular vibrations as a source of mediation for superconducting pairing of charge-carriers. In contrast to this result, our study shows the absence of an isotope effect within a precision of {plus_minus} 0.1 K.({approximately} l%), indicating that the central atom C=C stretching motion ({approximately} 1500 cm{sup {minus}1}) of ET cannot be a dominant mechanism for phonon exchange. Our results are consistent with those of a very recent study of the same isotope effect for {kappa}-(ET){sub 2}Cu[N(CN){sub 2}]Br and {kappa}-(ET){sub 2}Cu(NCS){sub 2} [Inorg. Chem., 32, 3356 (1992)].

Carlson, K.D.; Williams, J.M.; Geiser, U.; Kini, A.M.; Wang, H.H.; Klemm, R.A.; Kumar, S.K.; Schlueter, J.A.; Ferraro, J.R.; Lykke, K.R.; Wurz, P.; Sutin, J.D.B. [Argonne National Lab., IL (United States); Parker, D.H. [Argonne National Lab., IL (United States)]|[California Univ., Irvine, CA (United States). Dept. of Chemistry; Schirber, J.E.; Venturini, E.L. [Sandia National Labs., Albuquerque, NM (United States); Stout, P. [Bio-Rad, Cambridge, MA (United States). Digilab Division

1992-09-01T23:59:59.000Z

154

NEANDC specialists meeting on yields and decay data of fission product nuclides  

SciTech Connect

Separate abstracts were prepared for the 29 papers presented. Workshop reports on decay heat, fission yields, beta- and gamma-ray spectroscopy, and delayed neutrons are included. An appendix contains a survey of the most recent compilations and evaluations containing fission product yield, fission product decay data, and delayed neutron yield information. (WHK)

Chrien, R.E.; Burrows, T.W. (eds.)

1983-01-01T23:59:59.000Z

155

update: Decomposing beta diversity  

E-Print Network (OSTI)

on Island Biological Diversity is to influence the policy-update Decomposing beta diversity Baselga (2009) proposes apatterns of beta diversity into effects of nestedness and

Gotelli, Nicholas J.

2009-01-01T23:59:59.000Z

156

The neutron long counter NERO for studies of beta-delayed neutron emission in the r-process  

E-Print Network (OSTI)

The neutron long counter NERO was built at the National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, for measuring beta-delayed neutron-emission probabilities. The detector was designed to work in conjunction with a beta-decay implantation station, so that beta decays and beta-delayed neutrons emitted from implanted nuclei can be measured simultaneously. The high efficiency of about 40%, for the range of energies of interest, along with the small background, are crucial for measuring beta-delayed neutron emission branchings for neutron-rich r-process nuclei produced as low intensity fragmentation beams in in-flight separator facilities.

J. Pereira; P. Hosmer; G. Lorusso; P. Santi; A. Couture; J. Daly; M. Del Santo; T. Elliot; J. Goerres; C. Herlitzius; K. -L. Kratz; L. O. Lamm; H. Y. Lee; F. Montes; M. Ouellette; E. Pellegrini; P. Reeder; H. Schatz; F. Schertz; L. Schnorrenberger; K. Smith; E. Stech; E. Strandberg; C. Ugalde; M. Wiescher; A. Woehr

2010-07-28T23:59:59.000Z

157

Babar: Sin(2beta) With Charm  

Science Conference Proceedings (OSTI)

We present measurements of time-dependent CP asymmetries of neutral B decays to several charm and charmonium final states. Data have been collected with the BABAR detector at the PEP-II storage ring at the Stanford Linear Accelerator Center. In the absence of penguin contribution, the Standard Model predicts the time-dependent CP asymmetry parameters S and C are to be {eta}{sub CP} sin(2{beta}) and 0, respectively.

Grenier, P.; /Ecole Polytechnique /Clermont-Ferrand U.

2006-04-12T23:59:59.000Z

158

Higgs boson interactions in supersymmetric theories with large tan beta  

E-Print Network (OSTI)

We show that radiative corrections to the Higgs potential in supersymmetric theories with large tan beta generically lead to large differences in the light Higgs boson decay branching fractions compared to those of the standard model Higgs boson. In contrast, the light Higgs boson production rates are largely unaffected. We identify W h associated production followed by Higgs boson decays to photons or to leptons via W W* as potential experimental probes of these theories.

Will Loinaz; James D. Wells

1998-08-10T23:59:59.000Z

159

B Decay Length  

NLE Websites -- All DOE Office Websites (Extended Search)

Threshold Decay Length Threshold Decay Length Data from 292 B events are in an Excel spreadsheet that looks like this table. To find the threshold decay length: Sort the data by descending decay lengths, dt. Run Event No. B Mass GeV/c2 ptB GeV/c dt cm Velocity v/c Lab Lifetime sec Rest Lifetime sec Bin 65160 642324 5.277 7.966 0.388 66500 89978 5.274 20.508 0.940 Get the data. Make a histogram of decay lengths. Rather than graphing all the lengths as individual points, physicists group the data. They consider the range of the data and divide it into "bins" of equal size. A histogram is a graph of the number of events in each bin vs. the bin range. We are looking for the smallest decay length that fits the exponential curve. This will indicate the length of the decay as detemined by that experimental run.

160

Neutron beta-decay, Standard Model and cosmology  

E-Print Network (OSTI)

The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. The neutron lifetime recently obtained, 878.5 +/- 0.7stat +/- 0.3sys s, is the most accurate one to date. The new result for the neutron lifetime differs from the world average value by 6.5 standard deviations. The impact of the new result on testing of Standard Model and on data analysis for the primordial nucleosynthesis model is scrutinized.

A. P. Serebrov

2006-11-22T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Flavor SU(3) analysis of charmless $B$ meson decays to two pseudoscalar mesons  

E-Print Network (OSTI)

Global fits to charmless B --> PP decays in the framework of flavor SU(3) symmetry are updated and improved without reference to the \\sin2\\beta measured from the charmonium decay modes. Fit results directly constrain the (\\bar\\rho,\\bar\\eta) vertex of the unitarity triangle, and are used to predict the branching ratios and CP asymmetries of all decay modes, including those of the B_s system. Different schemes of SU(3) breaking in decay amplitude sizes are analyzed. The major breaking effect between strangeness-conserving and strangeness-changing decays can be accounted for by including a ratio of decay constants in tree and color-suppressed amplitudes. The possibility of having a new physics contribution to K \\pi decays is also examined from the data fitting point of view.

Chiang, C W; Chiang, Cheng-Wei; Zhou, Yu-Feng

2006-01-01T23:59:59.000Z

162

The search for proton decay  

Science Conference Proceedings (OSTI)

Following a very brief description of the theoretical developments which motivated the search for proton decay

R. Bionta; G. Blewitt; C. B. Bratton; D. Casper; B. G. Cortez; G. W. Foster; W. Gajewski; K. S. Ganezer; M. Goldhaber; T. J. Haines; T. W. Jones; D. Kielczewka; W. R. Kropp; J. G. Learned; E. Lehmann; J. M. LoSecco; H. S. Park; J. Shultz; S. Seidel; H. W. Sobel; J. L. Stone; L. R. Sulak; J. C. van der Velde

1984-01-01T23:59:59.000Z

163

Observation of New Charmless Decays of Bottom Hadrons  

SciTech Connect

The authors search for new charmless decays of neutral b-hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb{sup -1} of integrated luminosity, they report the first observation of the B{sub s}{sup 0} {yields} K{sup +}{pi}{sup +} decay, with a significance of 8.2{sigma}, and measure {Beta}(B{sub s}{sup 0} {yields} K{sup -}{pi}{sup +}) = (5.0 {+-} 0.7 (stat.) {+-} 0.8 (syst.)) x 10{sup -6}. They also report the first observation of charmless b-baryon decays in the channels {Lambda}{sub b}{sup 0} {yields} p{pi}{sup -} and {Lambda}{sub b}{sup 0} {yields} pK{sup -} with significances of 6.0{sigma} and 11.5{sigma} respectively, and they measure {Beta}({Lambda}{sub b}{sup 0} {yields} p{pi}{sup -}) = (3.5 {+-} 0.6 (stat.) {+-} 0.9 (syst.)) x 10{sup -6} and {Beta}({Lambda}{sub b}{sup 0} {yields} pK{sup -}) = (5.6 {+-} 0.8 (stat.) {+-} 1.5 (syst.)) x 10{sup -6}. No evidence is found for the decays B{sup 0} {yields} K{sup +}K{sup -} and B{sub s}{sup 0} {yields} {pi}{sup +}{pi}{sup -}, and they set an improved upper limit {Beta}(B{sub s}{sup 0} {yields} {pi}{sup +}{pi}{sup -}) < 1.2 x 10{sup -6} at the 90% confidence level. All quoted branching fractions are measured using {Beta}(B{sup 0} {yields} K{sup +}{pi}{sup -}) as a reference.

Morello, Michael J.; /Fermilab

2010-02-01T23:59:59.000Z

164

A Search for Neutrinoless Tau Decays to Three Leptons  

SciTech Connect

Using approximately 350 million {tau}{sup +}{tau}{sup -} pair events recorded with the BaBar detector at the Stanford Linear Accelerator Center between 1999 and 2006, a search has been made for neutrinoless, lepton-flavor violating tau decays to three lighter leptons. All six decay modes consistent with conservation of electric charge and energy have been considered. With signal selection efficiencies of 5-12%, we obtain 90% confidence level upper limits on the branching fraction {Beta}({tau} {yields} {ell}{ell}{ell}) in the range (4-8) x 10{sup -8}.

Kolb, Jeffrey A.; /Oregon U. /SLAC

2008-09-24T23:59:59.000Z

165

Double Crystal Analyzer System  

Science Conference Proceedings (OSTI)

... 2002 Page 2. Bloomberg Center for Physics & Astronomy • Johns Hopkins University • Baltimore • Maryland MACS Double ...

2002-02-25T23:59:59.000Z

166

Simultaneous Spin-Charge Relaxation in Double Quantum Dots  

E-Print Network (OSTI)

We investigate phonon-induced spin and charge relaxation mediated by spin-orbit and hyperfine interactions for a single electron confined within a double quantum dot. A simple toy model incorporating both direct decay to the ground state of the double dot and indirect decay via an intermediate excited state yields an electron spin relaxation rate that varies non-monotonically with the detuning between the dots. We confirm this model with experiments performed on a GaAs double dot, demonstrating that the relaxation rate exhibits the expected detuning dependence and can be electrically tuned over several orders of magnitude. Our analysis suggests that spin-orbit mediated relaxation via phonons serves as the dominant mechanism through which the double-dot electron spin-flip rate varies with detuning.

V. Srinivasa; K. C. Nowack; M. Shafiei; L. M. K. Vandersypen; J. M. Taylor

2013-03-07T23:59:59.000Z

167

Suppressed Charmed B Decay  

SciTech Connect

This thesis describes the measurement of the branching fractions of the suppressed charmed B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decays and the non-resonant B{sup 0} {yields} D{sup (*)-} {eta}{pi}{sup +} decays in approximately 230 million {Upsilon}(4S) {yields} B{bar B} events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10{sup -6}. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle {gamma}, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle {gamma} can be performed using the decays of neutral B mesons. The B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decay is sensitive to the angle {gamma} and, in comparison to the current decays that are being employed, could significantly enhance the measurement of this angle. However, the low expected branching fraction for the B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decay channels could severely impact the measurement. A prerequisite of the measurement of the CKM angle is the observation of the B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decay on which this thesis reports. The BABAR experiment consists of the BABAR detector and the PEP-II e{sup +}e{sup -} collider. The design of the experiment has been optimized for the study of CP violation in the decays of neutral B mesons but is also highly suitable for the search for rare B decays such as the B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decay. The PEP-II collider operates at the {Upsilon}(4S) resonance and is a clean source of B{bar B} meson pairs.

Snoek, Hella Leonie; /Vrije U., Amsterdam

2011-11-28T23:59:59.000Z

168

Exclusive decay of $?$ into $J/?+?_{c0,1,2}$  

E-Print Network (OSTI)

We study the $\\Upsilon$ exclusive decay into double charmonium, specifically, the $S$-wave charmonium $ J/\\psi$ plus the $P$-wave charmonium $\\chi_{c0,1,2}$ in the NRQCD factorization framework. Three distinct decay mechanisms, i.e., the strong, electromagnetic and radiative decay channels are included and their interference effects are investigated. The decay processes $\\Upsilon(1S,2S,3S)\\to J/\\psi+\\chi_{c1,0}$ are predicted to have the branching fractions of order $10^{-6}$, which should be observed in the prospective Super $B$ factory.

Jia Xu; Hai-Rong Dong; Feng Feng; Ying-Jia Gao; Yu Jia

2012-12-14T23:59:59.000Z

169

Exclusive decay of $\\Upsilon$ into $J/\\psi+\\chi_{c0,1,2}$  

E-Print Network (OSTI)

We study the $\\Upsilon$ exclusive decay into double charmonium, specifically, the $S$-wave charmonium $ J/\\psi$ plus the $P$-wave charmonium $\\chi_{c0,1,2}$ in the NRQCD factorization framework. Three distinct decay mechanisms, i.e., the strong, electromagnetic and radiative decay channels are included and their interference effects are investigated. The decay processes $\\Upsilon(1S,2S,3S)\\to J/\\psi+\\chi_{c1,0}$ are predicted to have the branching fractions of order $10^{-6}$, which should be observed in the prospective Super $B$ factory.

Xu, Jia; Feng, Feng; Gao, Ying-Jia; Jia, Yu

2013-01-01T23:59:59.000Z

170

Semileptonic Decays and Sides of the Unitarity Triangle  

SciTech Connect

The elements of the CKM matrix enter the expressions for the decay rates and mixing amplitudes of hadrons. In some cases, the theoretical expressions are free of strong interaction effects, for example the CP asymmetry in B {yields} J/{psi} K{sub S}{sup 0}, so that measuring the CP asymmetry directly gives the value of sin 2{beta}, with the error in the result given by the experimental error in the measurement. In most cases, however, the experimentally measured quantities depend on strong interactions physics, and it is absolutely essential to have accurate model-free theoretical calculations to compare with experiment. A number of theoretical tools have been developed over the years which now allow us to compute B decays with great accuracy, sometimes at the level of a few percent or better. These calculations are done using effective theory methods applied to QCD, and do not rely on model assumptions. Inclusive decays can be treated using the operator product expansion (OPE). The total decay rate is given by twice the imaginary part of the forward scattering amplitude, using the optical theorem. In heavy hadron decays, the intermediate states in the forward scattering amplitude can be integrated out, so that the decay rate can be written as an expansion in local operators. The expansion parameter is 1/m{sub B}, the mass of the decaying hadron. OPE techniques have been well-studied in the context of deep-inelastic scattering, where the expansion in powers of 1/Q{sup 2} is called the twist expansion. In inclusive B decays, the leading term in the 1/m{sub B} expansion gives the parton decay rate, and nonperturbative effects enter at higher orders in 1/m{sub B}.

Ligeti, Zoltan; Bauer, C.; Bernard, C.; Bigi, I.; Datta, M.; del Re, D.; Grinstein, B.; Hashimoto, S.; Langenegger, U.; Ligeti, Z.; Luke, M.; Lunghi, E.; Mackenzie, P.; Manohar, A.; Moore, T.; Pirjol, D.; Robertson, S.; Rothstein, I.; Stewart, I.; Voloshin, M.

2003-05-01T23:59:59.000Z

171

Search for Charged Lepton Violation in Narrow Upsilon Decays  

SciTech Connect

Charged lepton flavor violating processes are unobservable in the standard model, but they are predicted to be enhanced in several extensions to the standard model, including supersymmetry and models with leptoquarks or compositeness. We present a search for such processes in a sample of 99 x 10{sup 6} {Upsilon}(2S) decays and 117 x 10{sup 6} {Upsilon}(3S) decays collected with the BABAR detector. We place upper limits on the branching fractions {Beta}({Upsilon}(nS) {yields} e{sup {+-}}{tau}{sup {-+}}) and {Beta}({Upsilon}(nS) {yields} {mu}{sup {+-}}{tau}{sup {-+}}) (n = 2, 3) at the 10{sup -6} level and use these results to place lower limits of order 1 TeV on the mass scale of charged lepton flavor violating effective operators.

Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /LBL, Berkeley /UC, Berkeley; Hawkes, C.M.; /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Columbus Supercond., Genova /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-19T23:59:59.000Z

172

Hyperon radiative decay  

SciTech Connect

The radiative decay widths of the low-lying strange baryons are calculated both within the relativistic quark bag model and the nonrelativistic potential model. These widths are found to depend sensitively upon the quark-model dynamics through multiplet mixing and q/sup 4/q-bar admixtures. The comparison between our calculated results and the very limited experimental data is discussed.

Kaxiras, E.; Moniz, E.J.; Soyeur, M.

1985-08-01T23:59:59.000Z

173

Kinetic Alfven double layer formed by electron viscosity  

SciTech Connect

The effect of the electron viscosity on the kinetic Alfven solitary wave is investigated. It is found that small electron viscosity changes the electron motion along the magnetic field producing a boundary layer, and thus that in a low beta electron-ion plasma({beta} Much-Less-Than m{sub e}/m{sub i}), an obliquely propagating kinetic solitary Alfven wave can become a double layer. This double layer can exist in the sub-Alfvenic and super-Alfvenic regimes. The length scale of density drop for this double layer is on the order of that of the conventional kinetic solitary Alfven wave, and thus this double layer can accelerate electrons on a very short length scale.

Woo, M. H.; Ryu, C.-M. [Department of Physics, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Choi, C. R. [Department of Physics, Korea Advanced Institute of Science and Technology, Taejon 305-701 (Korea, Republic of)

2012-07-15T23:59:59.000Z

174

The Decay of Convective Turbulence  

Science Conference Proceedings (OSTI)

Using simulations with a large-eddy model we have studied the decay of convective turbulence in the atmospheric boundary layer when the upward surface sensible heat flux is suddenly stopped. The decay of turbulent kinetic energy and temperature ...

F. T. M. Nieuwstadt; R. A. Brost

1986-03-01T23:59:59.000Z

175

The double-arm barn door tracker  

NLE Websites -- All DOE Office Websites (Extended Search)

How to build a double-arm barn door tracker How to build a double-arm barn door tracker | Jefferson Lab Home Page | Science Education Home Page | Construction Notes/Photos Page | Sources: Sky & Telescope April 1989 (p436 - p441) [very good] Sky & Telescope February 1988 (p213 - p214) Original concept by Dave Trott A single-arm barn door tracker, driven by a straight screw, accumulates tangent error as time passes. Most of this error can be eliminated by adding a second hinged arm to the standard arrangement. There are four types of double-arm trackers, each with a different geometry. A comparison of accumulated error (in arc seconds) and construction parameters is given below: Error Chart [Apparently Type 1 is very bad and not worth constructing?? The two Type 4 drives vary in beta. This results in shifting the region of maximum error

176

Nuclear decay data files of the Dosimetry Research Group  

Science Conference Proceedings (OSTI)

This report documents the nuclear decay data files used by the Dosimetry Research Group at Oak Ridge National Laboratory and the utility DEXRAX which provides access to the files. The files are accessed, by nuclide, to extract information on the intensities and energies of the radiations associated with spontaneous nuclear transformation of the radionuclides. In addition, beta spectral data are available for all beta-emitting nuclides. Two collections of nuclear decay data are discussed. The larger collection contains data for 838 radionuclides, which includes the 825 radionuclides assembled during the preparation of Publications 30 and 38 of the International Commission on Radiological Protection (ICRP) and 13 additional nuclides evaluated in preparing a monograph for the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. The second collection is composed of data from the MIRD monograph and contains information for 242 radionuclides. Abridged tabulations of these data have been published by the ICRP in Publication 38 and by the Society of Nuclear Medicine in a monograph entitled ``MIRD: Radionuclide Data and Decay Schemes.`` The beta spectral data reported here have not been published by either organization. Electronic copies of the files and the utility, along with this report, are available from the Radiation Shielding Information Center at Oak Ridge National Laboratory.

Eckerman, K.F.; Westfall, R.J.; Ryman, J.C.; Cristy, M.

1993-12-01T23:59:59.000Z

177

The Beta Maxwell Distribution.  

E-Print Network (OSTI)

??In this work we considered a general class of distributions gener- ated from the logit of the beta random variable. We looked at various works… (more)

Amusan, Grace Ebunoluwa

2010-01-01T23:59:59.000Z

178

Handbook on string decay  

E-Print Network (OSTI)

We explain simple semi-classical rules to estimate the lifetime of any given highly-excited quantum state of the string spectrum in flat spacetime. We discuss both the decays by splitting into two massive states and by massless emission. As an application, we study a solution describing a rotating and pulsating ellipse which becomes folded at an instant of time -- the ``squashing ellipse''. This string interpolates between the folded string with maximum angular momentum and the pulsating circular string. We explicitly compute the quantum decay rate for the corresponding quantum state, and verify the basic rules that we propose. Finally, we give a more general (4-parameter) family of closed string solutions representing rotating and pulsating elliptical strings.

Roberto Iengo; Jorge G. Russo

2006-01-11T23:59:59.000Z

179

Rare Decays of the $?^{'}$  

E-Print Network (OSTI)

We have searched for the rare decays of the eta prime meson to e+ e- eta, e+ e- pizero, e+ e- gamma, and e mu in hadronic events at the CLEO II detector. The search is conducted on 4.80 fb^-1 of e+ e- collisions at the Cornell Electron Storage Ring. We find no signal in any of these modes, and set 90% confidence level upper limits on their branching fractions of 2.4 X 10^-3, 1.4 X 10^-3, 0.9 X 10^-3, and 4.7 X 10^-4, respectively. We also investigate the Dalitz plot of the common decay of the eta prime to pi+ pi- eta. We fit the matrix element with the Particle Data Group parameterization and find Re(alpha) = -0.021 +- 0.025, where alpha is a linear function of the kinetic energy of the eta.

R. A. Briere

1999-07-23T23:59:59.000Z

180

Recent Results in Semileptonic B Decays with BaBar  

SciTech Connect

In this note, recent results of studies of semileptonic B meson decays from BABAR are discussed and preliminary results given. In particular, a recent measurement of {Beta}(B {yields} D{sup (*)}{tau}{nu}) and the ratio {Beta}(B {yields} D{sup (*)}{tau}{nu})/{Beta}(B {yields} D{sup (*)}{ell}{nu}) is presented. For the D* mode, a branching fraction of 1.79 {+-} 0.13(stat) {+-} 0.17(syst) is found, with a ratio of 0.325 {+-} 0.023(stat) {+-} 0.027(syst). For the D mode, the results are 1.04 {+-} 0.12(stat) {+-} 0.14(syst) and 0.456 {+-} 0.053(stat) {+-} 0.056(syst), respectively. In addition, a study of B{sub s} production and semileptonic decays using data collected in a center-of-mass energy region above the {Upsilon}(4S) resonance is discussed. The semileptonic branching fraction {Beta}(B{sub s} {yields} {ell}{nu}X) is measured to be 9.9{sub -2.1}{sup +2.6}(stat){sub -2.0}{sup +1.3}(syst).

Hamilton, B.K.; /Maryland U.

2012-04-02T23:59:59.000Z

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181

Radioactive decay data tables  

SciTech Connect

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 fusion reactor technology, and some of those of interest to Committee 2 of the International Commission on Radiological Protection for the estimation of annual limits on intake via inhalation and ingestion for occupationally exposed individuals.

Kocher, D.C.

1981-01-01T23:59:59.000Z

182

Note on unparticle decays  

Science Conference Proceedings (OSTI)

The coupling of an unparticle operator O{sub U} to standard model particles opens up the possibility of unparticle decays into standard model fields. We study this issue by analyzing the pole structure (and spectral function) of the unparticle propagator, corrected to account for one-loop polarization effects from virtual standard model particles. We find that the propagator of a scalar unparticle (of scaling dimension 1{<=}d{sub U}<2) with a mass gap m{sub g} develops an isolated pole, m{sub p}{sup 2}-im{sub p}{gamma}{sub p}, with m{sub p}{sup 2} < or approx. m{sub g}{sup 2} below the unparticle continuum that extends above m{sub g} (showing that the theory would be unstable without a mass gap). If that pole lies below the threshold for decay into two standard model particles, it corresponds to a stable unparticle state (and its width {gamma}{sub p} is zero). For m{sub p}{sup 2} above the threshold, the width is nonzero and related to the rate of the unparticle decay into standard model particles. This picture is valid for any value of d{sub U} in the considered range.

Delgado, Antonio [Department of Physics, 225 Nieuwland Science Hall, University of Notre Dame, Notre Dame, Indiana 46556-5670 (United States); Espinosa, Jose R. [IFT-UAM/CSIC, Facultad Ciencias UAM, 28049 Madrid (Spain); IFAE, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain) and ICREA, Institucio Catalana de Recerca i Estudis Avancats, Barcelona (Spain); No, Jose Miguel [IFT-UAM/CSIC, Facultad Ciencias UAM, 28049 Madrid (Spain); Quiros, Mariano [IFAE, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain) and ICREA, Institucio Catalana de Recerca i Estudis Avancats, Barcelona (Spain); Theory Division, CERN, Geneva 23 CH-1211 (Switzerland)

2009-03-01T23:59:59.000Z

183

Search for Hadronic Decays of a Light Higgs Boson in the Radiative Decay  

Science Conference Proceedings (OSTI)

The authors search for hadronic decays of a light Higgs boson (A{sup 0}) produced in radiative decays of an {Upsilon}(2S) or {Upsilon}(3S) meson, {Upsilon} {yields} {gamma}A{sup 0}. The data have been recorded by the BABAR experiment at the {Upsilon}(3S) and {Upsilon}(2S) center of mass energies, and include (121.3 {+-} 1.2) x 10{sup 6} {Upsilon}(3S) and (98.3 {+-} 0.9) x 10{sup 6} {Upsilon}(2S) mesons. No significant signal is observed. We set 90% confidence level upper limits on the product branching fractions {beta}({Upsilon}(nS) {yields} {gamma}A{sup 0}) {center_dot} {beta}(A{sup 0} {yields} hadrons) (n = 2 or 3) that range from 1 x 10{sup -6} for an A{sup 0} mass of 0.3 GeV/c{sup 2} to 8 x 10{sup -5} at 7 GeV/c{sup 2}.

Lees, J.P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Milanes, D.A.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Koch, H.; Schroeder, T.; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.

2012-02-16T23:59:59.000Z

184

E6 Gamma Decay  

SciTech Connect

Rare electric hexacontatetrapole (E6) transitions are studied in the full (f{sub 7/2},f{sub 5/2},p{sub 3/2},p{sub 1/2}) shell-model basis. Comparison of theory to the results from the gamma decay in {sup 53}Fe and from inelastic electron scattering on {sup 52}Cr provides unique and interesting tests of the valence wavefunctions, the models used for energy density functionals and into the origin of effective charge.

Brown, B. Alex [Department of Physics and Astronomy, and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824-1321 (United States); Rae, W. D. M. [Knollhouse, Garsington, Oxford, Oxfordshire, OX44 9DB (United Kingdom)

2011-05-06T23:59:59.000Z

185

Rare B Decays  

SciTech Connect

Recent results from Belle and BaBar on rare B decays involving flavor-changing neutral currents or purely leptonic final states are presented. Measurements of the CP asymmetries in B {yields} K*{gamma} and b {yields} s{gamma} are reported. Also reported are updated limits on B{sup +} {yields} K{sup +}{nu}{bar {nu}}, B{sup +} {yields} {tau}{sup +}{nu}, B{sup +} {yields} {mu}{sup +}{nu} and the recent measurement of B {yields} X{sub s}{ell}{sup +}{ell}{sup -}.

Jackson, P.D.; /Victoria U.

2006-02-24T23:59:59.000Z

186

High-beta tokamak  

DOE Green Energy (OSTI)

Calculations are made to study the stability and accessibility of tokamak plasmas in the high energy density regime which is desirable for economical reactor operation. Results are given from flux conserving tokamak (FCT) models, classical models, and more complete models with spatially resolved (R,Z) transport, including effects from sawtooth oscillations and magnetic islands. MHD equilibrium, stability, and transport calculations are made to study the accessibility and behavior of high-beta tokamak plasmas in the range {beta} {approx} 5-15%. For next-generation devices, beta values of, at least, 8% appear to be accessible and stable if there is a conducting surface nearby.

Dory, R.A. [Oak Ridge National Laboratory (ORNL); Berger, D.P. [Oak Ridge National Laboratory (ORNL); Charlton, L. A. [Oak Ridge National Laboratory (ORNL); Hogan, J.T. [Oak Ridge National Laboratory (ORNL); Munro, J.K. [Oak Ridge National Laboratory (ORNL); Nelson, D. B. [Oak Ridge National Laboratory (ORNL); Peng, Yueng Kay Martin [ORNL; Sigma, D.J. [Oak Ridge National Laboratory (ORNL); Strickler, Dennis J [ORNL

1979-01-01T23:59:59.000Z

187

Precision Measurements of Tau Lepton Decays  

SciTech Connect

Using data collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy near 10.58 GeV, the branching fractions {Beta}({tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}) = (8.83 {+-} 0.01 {+-} 0.13)%, {Beta}({tau}{sup -} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}) = (0.273 {+-} 0.002 {+-} 0.009)%, {Beta}({tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}}) = (0.1346 {+-} 0.0010 {+-} 0.0036)%, and {Beta}({tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}}) = (1.58 {+-} 0.13 {+-} 0.12) x 10{sup -5} are measured where the uncertainties are statistical and systematic, respectively. The invariant mass distribution for the {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}, {tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}} and {tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}} decays are unfolded to correct for detector effects. A measurement of {Beta}({tau}{sup -} {yields} {phi}{pi}{sup -}{nu}{sub {tau}}) = (3.42 {+-} 0.55 {+-} 0.25) x 10{sup -5}, a measurement of {Beta}({tau}{sup -} {yields} {phi}K{sup -}{nu}{sub {tau}}) = (3.39 {+-} 0.20 {+-} 0.28) x 10{sup -5} and an upper limit on {Beta}({tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}}[ex.{phi}]) {le} 2.5 x 10{sup -6} {at} 905 CL are determined from a binned maximum likelihood fit of the {tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}} and {tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}} K{sup +}K{sup -} invariant mass distributions. The branching ratio {Beta}({tau}{sup -} {yields} K{sup -}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} {pi}{sup -}{nu}{sub {tau}}) is measured to be (6.531 {+-} 0.056 {+-} 0.093) x 10{sup -2} from which |V{sub us}| is determined to be 0.2255 {+-} 0.0023. The branching ratio {Beta}/({tau}{sup -} {yields} {mu}{nu}{sub {tau}}{bar {nu}}{sub {mu}})/{Beta}({tau}{sup -} {yields} e{sup -} {nu}{sub {tau}}{bar {nu}}{sub e}) = (9.796 {+-} 0.016 {+-} 0.035) x 10{sup -1} is measured enabling a precision test of the Standard Model assumption of charged current lepton universality, g{sub {mu}}/g{sub e} = 1.0036 {+-} 0.0020. The branching ratios {Beta}({tau}{sup -} {yields} K{sup -}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} e{sup -}{nu}{sub {tau}}{bar {nu}}{sub e}) = (3.882 {+-} 0.032 {+-} 0.057) x 10{sup -2}, and {Beta}({tau}{sup -} {yields} {pi}{sup -}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} e{nu}{sub {tau}}{bar {nu}}{sub e}) = (5.9545 {+-} 0.014 {+-} 0.061) x 10{sup -1} are measured which provide additional tests of charged current lepton universality, (g{sub {tau}}/g{sub {mu}}){sub {pi}} = 0.9856 {+-} 0.0057 and (g{sub {tau}}/g{sub {mu}}){sub K} = 0.9827 {+-} 0.0086 which can be combined to give (g{sub {tau}}/g{sub {mu}}){sub {pi}/K} = 0.9850 {+-} 0.0054. Any deviation of these measurements from the expected Standard Model values would be an indication of new physics.

Nugent, Ian M.; /Victoria U.

2010-03-16T23:59:59.000Z

188

Diagnosing oscillatory growth or decay  

SciTech Connect

An analytical study is presented for an oscillatory system in terms of four constants, namely amplitude, phase, growth or decay rate, and frequency. (MOW)

Buneman, O.

1977-12-01T23:59:59.000Z

189

Ventilating Beta Plane Leases  

Science Conference Proceedings (OSTI)

The theory of warm water lenses on beta planes is extended to include heat exchange between the lenses and their environment. The motivation for this study comes from recent observations of Gulf Stream warm core rings, which clearly show that ...

William K. Dewar

1988-08-01T23:59:59.000Z

190

High-statistics measurement of the beta-delayed alpha spectrum of 20Na  

E-Print Network (OSTI)

A measurement of the 20Na beta-delayed alpha spectrum with a high-granularity set-up has allowed the decay scheme to be revised on several points. Three new transitions of low intensity are found at low alpha-particle energy. An R-matrix fit of the complete spectrum gives an improved description of the decay and indicates feeding to the broad 2^+ alpha-cluster state close to 9 MeV.

K. L. Laursen; O. S. Kirsebom; H. O. U. Fynbo; A. Jokinen; M. Madurga; K. Riisager.; A. Saastamoinen; O. Tengblad; J. Äysto

2013-04-09T23:59:59.000Z

191

The Particle Adventure | Particle decays and annihiliations ...  

NLE Websites -- All DOE Office Websites (Extended Search)

Particle decays and annihiliations - Half life A lump of uranium left to itself will gradually decay, one nucleus at a time. The rate of decay is measured by how long it would take...

192

Branching Fraction Measurement of B to omega l nu decays  

SciTech Connect

We present a measurement of the B{sup +} {yields} {omega}{ell}{sup +}{nu} branching fraction based on a sample of 467 million B{bar B} pairs recorded by the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} collider. We observe 1041 {+-} 133 signal decays, corresponding to a branching fraction of {Beta}(B{sup +} {yields} {omega}{ell}{sup +}{nu}) = (1.15 {+-} 0.15 {+-} 0.12) x 10{sup -4}, where the first error is statistical and the second is systematic. The dependence of the decay rate on q{sup 2}, the momentum transfer squared to the lepton system, is compared to QCD predictions of the form factors based on a quark model and light-cone sum rules.

Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Palano, A.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /LBL, Berkeley /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; So, R.Y.; /British Columbia U.; Khan, A.; /Brunel U.; Blinov, V.E.; /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U., Comp. Sci. Dept. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U.; /more authors..

2012-06-13T23:59:59.000Z

193

The Particle Adventure | Particle decays and annihiliations ...  

NLE Websites -- All DOE Office Websites (Extended Search)

virtual particles. Virtual particles do not violate the conservation of energy. The kinetic energy plus mass of the initial decaying particle and the final decay products is...

194

Double Degenerate Binary Systems  

Science Conference Proceedings (OSTI)

In this study, angular momentum loss via gravitational radiation in double degenerate binary (DDB)systems (NS + NS, NS + WD, WD + WD, and AM CVn) is studied. Energy loss by gravitational waves has been estimated for each type of systems.

Yakut, K. [University of Ege, Department of Astronomy and Space Sciences, 35100-Izmir (Turkey)

2011-09-21T23:59:59.000Z

195

Decay studies of the highly neutron-deficient indium isotopes  

Science Conference Proceedings (OSTI)

An extension of the experimentally known nuclidic mass surface to nuclei far from the region of beta-stability is of fundamental interest in providing a better determination of the input parameters for the various nuclear mass formulae, allowing a more accurate prediction of the ultimate limits of nuclear stability. In addition, a study of the shape of the mass surface in the vicinity of the doubly-closed nuclide /sup 100/Sn provides initial information on the behavior of the shell closure to be expected when Z = N = 50. Experiments measuring the decay energies of /sup 103/ /sup 105/In by ..beta..-endpoint measurements are described with special attention focused on the development of a plastic scintillator ..beta..-telescope coupled to the on-line mass separator RAMA (Recoil Atom Mass Analyzer). An attempt to measure the ..beta..-endpoint energy of /sup 102/In is also briefly described. The experimentally determined decay energies and derived masses for /sup 103/ /sup 105/In are compared with the predictions of different mass models to identify which models are more successful in this region. Furthermore, the inclusion in these comparisons of the available data on the neutron-rich indium nuclei permits a systematic study of their ground state mass behavior as a function of the neutron number between the shell closures at N = 50 and N = 82. These analyses indicate that the binding energy of /sup 103/In is 1 MeV larger than predicted by the majority of the mass models. An examination of the Q/sub EC/ surface and the single- and two-neutron separation energies in the vicinity of /sup 103/ /sup 105/In is also performed to investigate further the deviation and other possible systematic variations in the mass surface in a model-independent way.

Wouters, J.M.

1982-02-01T23:59:59.000Z

196

Study of Bbar to Xu l nubar Decays in BBbar Events Tagged by a Fully Reconstructed B-meson Decay and Determination of |V_{ub}|  

SciTech Connect

We report measurements of partial branching fractions for inclusive charmless semileptonic B decays {bar B} {yields} X{sub u}{ell}{bar {nu}}, and the determination of the CKM matrix element |V{sub ub}|. The analysis is based on a sample of 467 million {Upsilon}(4S) {yields} B{bar B} decays recorded with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. We select events in which the decay of one of the B mesons is fully reconstructed and an electron or a muon signals the semileptonic decay of the other B meson. We measure partial branching fractions {Delta}{Beta} in several restricted regions of phase space and determine the CKM element |V{sub ub}| based on four different QCD predictions. For decays with a charged lepton momentum p*{sub {ell}} > 1.0 GeV in the B meson rest frame, we obtain {Delta}{Beta} = (1.80 {+-} 0.13{sub stat.} {+-} 0.15{sub sys.} {+-} 0.02{sub theo.}) x 10{sup -3} from a maximum likelihood fit to the two-dimensional M{sub X} - q{sup 2} distribution. Here, M{sub X} refers to the invariant mass of the final state hadron X and q{sup 2} is the invariant mass squared of the charged lepton and neutrino. From this measurement we extract |V{sub ub}| = (4.31 {+-} 0.25{sub exp.} {+-} 0.16{sub theo.}) x 10{sup -3} as the arithmetic average of four results obtained from four different QCD predictions of the partial rate. We separately determine partial branching fractions for {bar B}{sup 0} and B{sup -} decays and derive a limit on the isospin breaking in {bar B} {yields} X{sub u}{ell}{bar {nu}} decays.

Lees, J.P.

2012-07-13T23:59:59.000Z

197

The decay of hot nuclei  

Science Conference Proceedings (OSTI)

The formation of hot compound nuclei in intermediate-energy heavy ion reactions is discussed. The statistical decay of such compound nuclei is responsible for the abundant emission of complex fragments and high energy gamma rays. 43 refs., 23 figs.

Moretto, L.G.; Wozniak, G.J.

1988-11-01T23:59:59.000Z

198

Overview of rare K decays  

Science Conference Proceedings (OSTI)

The status and future prospects of searches for and studies of forbidden and highly suppressed K decays are reviewed. Here the author discusses three areas of recent activity in rare K decay. These are lepton-flavor violating decays, which are entirely forbidden in the Standard Model, K{sub S} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0}, which is of interest from the point of view of CP-violation, and `one loop` decays of the form K{sup 0,{+-}} {yields} ({pi}{sup 0,{+-}})l{bar l}, that can throw light on Standard Model CP-violation and determine parameters such as V{sub td}.

Littenberg, L.

1995-05-01T23:59:59.000Z

199

Applied Beta Dosimetry  

SciTech Connect

Measurements of beta and/or nonpenetrating exposure results is complicated and past techniques and capabilities have resulted in significant inaccuracies in recorded results. Current developments have resulted in increased capabilities which make the results more accurate and should result in less total exposure to the work force. Continued development of works in progress should provide equivalent future improvements.

Rich, B.L.

1986-01-01T23:59:59.000Z

200

Barotropic Equatorial Waves: The Nonuniformity of the Equatorial Beta-Plane  

Science Conference Proceedings (OSTI)

Some equatorially trapped motions cannot be modeled by the equatorial beta-plane. Our proof is a counter-example: if the zonal wavenumber m is large, barotropic Rossby-Haurwitz waves decay with latitude outside a narrow band about the equator and ...

John P. Boyd

1985-09-01T23:59:59.000Z

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201

A Model-Independent Search for the decay B->l nu gamma  

SciTech Connect

The authors present a search for the radiative leptonic decay B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}}{gamma}, where {ell} = e, {mu}, using a data sample of 465 million B{bar B} pairs collected by the BABAR experiment. In this analysis, they fully reconstruct the hadronic decay of one of the B mesons in {Upsilon}(4S) {yields} B{sup +}B{sup -} decays, then search for evidence of B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}}{gamma} in the rest of the event. They observe no significant evidence of signal decays and report model-independent branching fraction upper limits of {Beta}(B{sup +} {yields} e{sup +}{nu}{sub e}{gamma}) < 17 x 10{sup -6}, {Beta}(B{sup +} {yields} {mu}{sup +}{nu}{sub {mu}}{gamma}) < 24 x 10{sup -6}, and {Beta}(B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}}{gamma}) < 15.6 x 10{sup -6} ({ell} = e or {mu}), all at the 90% confidence level.

Aubert, Bernard; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, David Nathan; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS; /more authors..

2012-10-09T23:59:59.000Z

202

Low energy weak interactions and decays. [Partial summary of presentations at XXth International Conf. on High Energy Physics, Madison, Wisc. , July 17-23, 1980  

SciTech Connect

Results presented during sessions B5 to 7 at the XXth International Conference on High Energy Physics (University of Wisconsin, Madison, July 17 to 23, 1980) are discussed. Essentially all the material presented is summarized. The sessions covered various aspects of low-energy weak interactions. The following topics are addressed: CP-invariance violation, high-statistics study of ..lambda.. beta decay, parity violation in proton-nucleus scattering at 6 GeV/c, new results on the tau, charm particle decays (direct lifetime determinations, semileptonic branching ratios, comparison of semileptonic rate with theoretical expectations, further study of charm meson decays, F decays), and neutrino oscillations. 6 figures, 9 tables. (RWR)

Trilling, G.H.

1980-09-01T23:59:59.000Z

203

The charged current neutrino cross section for solar neutrinos, and background to \\BBz\\ experiments  

E-Print Network (OSTI)

Solar neutrinos can interact with the source isotope in neutrinoless double beta decay experiments through charged current and neutral current interactions. The charged-current product nucleus will then beta decay with a Q-value larger than the double beta decay Q-value. As a result, this process can populate the region of interest and be a background to the double beta decay signal. In this paper we estimate the solar neutrino capture rates on three commonly used double beta decay isotopes, \

H. Ejiri; S. R. Elliott

2013-09-30T23:59:59.000Z

204

Measurements of B -> V gamma Decays  

SciTech Connect

The standard model has been highly successful at describing current experimental data. However, extensions of the standard model predict particles that have masses at energy scales that are above the electroweak scale. The flavor-changing neutral current processes of the B meson are sensitive to the influences of these new physics contributions. These processes proceed through loop diagrams, thus allowing new physics to enter at the same order as the standard model. New physics may contribute to the enhancement or suppression of rate asymmetries or the decay rates of these processes. The transition B {yields} V{gamma} (V = K*(892), {rho}(770), {omega}(782), {phi}(1020)) represents radiative decays of the B meson that proceed through penguin processes. Hadronic uncertainties limit the theoretical accuracy of the prediction of the branching fractions. However, uncertainties, both theoretical and experimental, are much reduced when considering quantities involving ratios of branching fractions, such as CP or isospin asymmetries. The most dominant exclusive radiative b {yields} s transition is B {yields} K*{gamma}. We present the best measurements of the branching fractions, direct CP, and isospin asymmetries of B {yields} K*{gamma}. The analogous b {yields} d transitions are B {yields} {rho}{gamma} and B {yields} {omega}{gamma}, which are suppressed by a factor of |V{sub td}/V{sub ts}|{sup 2} {approx} 0.04 relative to B {yields} K*{gamma}. A measurement of the branching fractions and isospin asymmetry of B{sup +} {yields} {rho}{sup +}{gamma} and B{sup 0} {yields} {rho}{sup 0}{gamma}, as well as a search for B {yields} {omega}{gamma}, are also given. These measurements are combined to calculate the ratio of CKM matrix elements |V{sub td}/V{sub ts}|, which corresponds to the length of one side of the unitary triangle. Finally, we present a search for the penguin annihilation process B {yields}{phi}{gamma}. We use a sample of 383 million B{bar B} events collected with the BABAR detector at the PEP-II asymmetric-energy B factory for the analysis of B {yields} K*{gamma}. We measure the branching fractions {Beta}(B{sup 0} {yields} K*{sup 0}{gamma}) = (4.47 {+-} 0.10 {+-} 0.16) x 10{sup -5} and {Beta}(B{sup +} {yields} K*{sup +}{gamma}) = (4.22 {+-} 0.14 {+-} 0.16) x 10{sup -5}. We measure the direct CP asymmetry to be -0.033 < {Alpha}{sub CP} (B {yields} K*{gamma}) < 0.028 and the isospin asymmetry to be 0.017 < {Delta}{sub 0-} < 0.116, where the limits are determined at the 90% C.L. and include both the statistical and systematic uncertainties. Using a sample of 347 million B{bar B} events, we measure the branching fractions {Beta}(B{sup +} {yields} {rho}{sup +}{gamma}) = (1.10{sub -0.33}{sup +0.37} {+-} 0.09) x 10{sup -6} and {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) = (0.79{sub -0.20}{sup +0.22} {+-} 0.06) x 10{sup -6}, the isospin asymmetry {Delta} = -0.35 {+-} 0.27, and set a 90% C.L. upper limit {Beta}(B {yields} {omega}{gamma}) < 0.78 x 10{sup -6}. We also measure the isospin-averaged branching fraction {Beta}(B {yields} ({rho}/{omega}){gamma}) = (1.25{sub -0.24}{sup +0.25} {+-} 0.09) x 10{sup -6}, from which we determine |V{sub td}/V{sub ts}|= 0.200{sub -0.020}{sup +0.021} {+-} 0.015, where the first uncertainty is experimental and the second theoretical. Finally, a sample of 124 million B{bar B} events is used to set an upper limit of {Beta}(B {yields} {phi}{gamma}) < 8.5 x 10{sup -7} at the 90% C.L.

Yarritu, Aaron K.; /Stanford U., Phys. Dept.

2010-09-02T23:59:59.000Z

205

Laser-induced synthesis and decay of Tritium under exposure of solid targets in heavy water  

E-Print Network (OSTI)

The processes of laser-assisted synthesis of Tritium nuclei and their laser-induced decay in cold plasma in the vicinity of solid targets (Au, Ti, Se, etc.) immersed into heavy water are experimentally realized at peak laser intensity of 10E10-10E13 Watts per square centimeter. Initial stages of Tritium synthesis and their laser-induced beta-decay are interpreted on the basis of non-elastic interaction of plasma electrons having kinetic energy of 5-10 eV with nuclei of Deuterium and Tritium, respectively.

E. V. Barmina; P. G. Kuzmin; S. F. Timashev; G. A. Shafeev

2013-06-03T23:59:59.000Z

206

CRBRP decay heat removal systems  

SciTech Connect

The Decay Heat Removal Systems for the Clinch River Breeder Reactor Plant (CRBRP) are designed to adequately remove sensible and decay heat from the reactor following normal shutdown, operational occurrences, and postulated accidents on both a short term and a long term basis. The Decay Heat Removal Systems are composed of the Main Heat Transport System, the Main Condenser and Feedwater System, the Steam Generator Auxiliary Heat Removal System (SGAHRS), and the Direct Heat Removal Service (DHRS). The overall design of the CRBRP Decay Heat Removal Systems and the operation under normal and off-normal conditions is examined. The redundancies of the system design, such as the four decay heat removal paths, the emergency diesel power supplies, and the auxiliary feedwater pumps, and the diversities of the design such as forced circulation/natural circulation and AC Power/DC Power are presented. In addition to overall design and system capabilities, the detailed designs for the Protected Air Cooled Condensers (PACC) and the Air Blast Heat Exchangers (ABHX) are presented.

Hottel, R.E.; Louison, R.; Boardman, C.E.; Kiley, M.J.

1977-01-01T23:59:59.000Z

207

A matterless double slit  

E-Print Network (OSTI)

Double-slits provide incoming photons with a choice. Those that survive the passage have chosen from two possible paths which interfere to distribute them in a wave-like manner. Such wave-particle duality continues to be challenged and investigated in a broad range of disciplines with electrons, neutrons, helium atoms, C60 fullerenes, Bose-Einstein condensates and biological molecules. All variants have hitherto involved material constituents. We present a matterless double-slit scenario in which photons generated from virtual electron-positron pair annihilation in head-on collisions of a probe laser field with two ultra-intense laser beams form a double-slit interference pattern. Such electromagnetic fields are predicted to induce material-like behaviour in the vacuum, supporting elastic scattering between photons. Our double-slit scenario presents on the one hand a realisable method to observe photon-photon scattering, and demonstrates on the other, the possibility of both controlling light with light and non-locally investigating features of the quantum vacuum's structure.

B. King; A. Di Piazza; C. H. Keitel

2013-01-29T23:59:59.000Z

208

DOUBLE MAJORS Imaging Science + ...  

E-Print Network (OSTI)

DOUBLE MAJORS Imaging Science + ... Applied Mathematics Biomedical Sciences Computer Science Undergraduate Research Internships and Cooperative Education (Co-op) (optional) Study Abroad WHY IMAGING SCIENCE Science: BS, MS, PhD Color Science: MS, PhD BS + MS/PhD Combos HUMAN VISION BIO- MEDICAL ASTRO- PHYSICS

Zanibbi, Richard

209

Double-digit growth  

SciTech Connect

The global need for additional generating capacity continues to grow at double digit rates in some cases. Opportunities for partnerships and joint ventures vary considerably by country and region. A closer look is taken at five countries where the playing fields are increasingly tipping to favor outside partners in power development projects -- India, Indonesia, Malaysia, Thailand, and Mexico.

Cartselos, T.; Meade, W.; Hernandez, L.

1993-09-01T23:59:59.000Z

210

Bioprospecting metagenomics of decaying wood: mining for new glycoside hydrolases  

DOE Green Energy (OSTI)

To efficiently deconstruct recalcitrant plant biomass to fermentable sugars in industrial processes, biocatalysts of higher performance and lower cost are required. The genetic diversity found in the metagenomes of natural microbial biomass decay communities may harbor such enzymes. Our goal was to discover and characterize new glycoside hydrolases (GHases) from microbial biomass decay communities, especially those from unknown or never previously cultivated microorganisms. From the metagenome sequences of an anaerobic microbial community actively decaying poplar biomass, we identified approximately 4,000 GHase homologs. Based on homology to GHase families/activities of interest and the quality of the sequences, candidates were selected for full-length cloning and subsequent expression. As an alternative strategy, a metagenome expression library was constructed and screened for GHase activities. These combined efforts resulted in the cloning of four novel GHases that could be successfully expressed in Escherichia coli. Further characterization showed that two enzymes showed significant activity on p-nitrophenyl-{alpha}-L-arabinofuranoside, one enzyme had significant activity against p-nitrophenyl-{beta}-D-glucopyranoside, and one enzyme showed significant activity against p-nitrophenyl-{beta}-D-xylopyranoside. Enzymes were also tested in the presence of ionic liquids. Metagenomics provides a good resource for mining novel biomass degrading enzymes and for screening of cellulolytic enzyme activities. The four GHases that were cloned may have potential application for deconstruction of biomass pretreated with ionic liquids, as they remain active in the presence of up to 20% ionic liquid (except for 1-ethyl-3-methylimidazolium diethyl phosphate). Alternatively, ionic liquids might be used to immobilize or stabilize these enzymes for minimal solvent processing of biomass.

Li L. L.; van der Lelie D.; Taghavi, S.; McCorkle, S. M.; Zhang, Y.-B.; Blewitt, M. G.; Brunecky, R.; Adney, W. S.; Himmel, M. E.; Brumm, P.; Drinkwater, C.; Mead, D. A.; Tringe, S. G.

2011-08-01T23:59:59.000Z

211

Gamma-ray decay schemes for $sup 93$Kr, $sup 93$Rb, and $sup 93$Sr  

SciTech Connect

A study of the gamma-ray de-excitation following the beta decays of $sup 93$Kr, $sup 93$Rb, and $sup 93$Sr using the TRISTAN on-line separator facility is reported. Gamma-ray singles and gamma-gamma coincidence measurements were made using Ge(Li) detectors. Of the 162 gamma rays observed in the decay of $sup 93$Sr, 143, representing more than 99 percent of the total gamma-ray intensity observed, were placed in a level scheme containing 36 levels. For the decay of $sup 93$Rb, 243 gamma rays were observed, of which 231 are placed in a level scheme consisting of 74 levels. This again represents a placement of over 99 percent of the total gamma-ray intensity measured. In the case of the $sup 93$Kr decay approximately 98.5 percent of the observed gamma-ray intensity has been accounted for by the proposed level scheme. This results from the placement of 203 of the 217 gamma rays assigned to this decay in a level scheme comprising 56 levels. Beta-branching for these decays were determined from transition intensity balances. Spin and parity assignments were proposed, whenever possible, on the basis of gamma-ray transition probabilities and deduced log ft values. A comparison is made with the available reaction data for the $sup 93$Y level scheme. In all cases an attempt has been made to explain some of the levels in terms of the nuclear shell model and decay systematics. 18 figures, 20 tables, 68 references. (auth)

Bischof, C.J.

1976-01-01T23:59:59.000Z

212

Selected Aspects of Neutron Decay  

E-Print Network (OSTI)

Precision measurements of neutron decay offer complementary access to particle physics at small distance scales or high energies. In particular they allow tests of the V-A structure of the weak interaction. Among many experimental activities which are ongoing around the world we present two new experiments which are planned or studied for the near future. While the neutron lifetime still bears significant experimental uncertainties and thus has to be studied with greatest precision the two-body decay ($n\\to H\\bar\

Stephan Paul

2005-04-18T23:59:59.000Z

213

Precision Measurement Of The Neutron's Beta Asymmetry Using Ultra-Cold Neutrons  

Science Conference Proceedings (OSTI)

A measurement of A{beta}, the correlation between the electron momentum and neutron (n) spin (the beta asymmetry) in n beta-decay, together with the n lifetime, provides a method for extracting fundamental parameters for the charged-current weak interaction of the nucleon. In particular when combined with decay measurements, one can extract the Vud element of the CKM matrix, a critical element in CKM unitarity tests. By using a new SD2 super-thermal source at LANSCE, large fluxes of UCN (ultra-cold neutrons) are expected for the UCNA project. These UCN will be 100% polarized using a 7 T magnetic field, and directed into the {beta} spectrometer. This approach, together with an expected large reduction in backgrounds, will result in an order of magnitude reduction in the critical systematic corrections associated with current n {beta}-asymmetry measurements. This paper will give an overview of the UCNA A{beta} measurement as well as an update on the status of the experiment.

Makela, M. [Los Alamos National Lab., P.O. Box 1663, Los Alamos, NM 87545 (United States); Back, H. O. [North Carolina State University Raleigh, NC 27695 (United States); Melconian, D. [University of Washington, Department of Physics, Box 351560 Seattle, WA 98195 (United States); Plaster, B. [California Institute of Technology, Kellogg Radiation Lab, Pasadena, CA 91125 (United States)

2006-07-11T23:59:59.000Z

214

Constraining |V(td)|/|V(ts)| Using Radiative Penguin B -> V(K*/rho/omega)gamma Decays  

SciTech Connect

Exclusive radiative penguin B decays, B {yields} (K*{sup 0}/K*{sup +}) and B {yields} ({rho}/{omega}){gamma}, are flavor-changing neutral-current (FCNC) processes. Studies of these decays are of special interest in testing Standard Model (SM) predictions and searching for other beyond-the-SM FCNC interactions. Using 89 x 10{sup 6} B{bar B} pairs from BABAR, we measure the branching fraction ({Beta}), CP-asymmetry ({Alpha}), and isospin asymmetry ({Delta}{sub 0-}) of B {yields} (K*{sup 0}/K*{sup +}){gamma} as follows: {Beta}(B{sup 0} {yields} K*{sup 0}{gamma}) = 3.92 {+-} 0.20(stat.) {+-} 0.24(syst.); {Beta}(B{sup +} {yields} K*{sup +}{gamma}) = 3.87 {+-} 0.28(stat.) {+-} 0.26(syst.); {Alpha}(B {yields} K*{gamma}) = -0.013 {+-} 0.36(stat.) {+-} 0.10(syst.); {Delta}{sub 0-}(B {yields} K*{gamma}) = 0.050 {+-} 0.045(stat.) {+-} 0.028(syst.) {+-} 0.024(R{sup +/0}). The 90% confidence intervals for the CP-asymmetry and the isospin-asymmetry in the B {yields} K*{gamma} decay are given as: -0.074 < {Alpha}(B {yields} K*{gamma}) < 0.049, -0.046 < {Delta}{sub 0-} (B {yields} K*{gamma}) < 0.146. We also search for B {yields} ({rho}/{omega}){gamma} decays using 211 x 10{sup 6} B{bar B} pairs from BABAR. No evidence for these decays is found. We set the upper limits at 90% confidence level for these decays: {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) < 0.4 x 10{sup -6}; {Beta}(B{sup +}{yields} {rho}{sup =}{gamma}) < 1.8 x 10{sup -6}; {Beta}(B{sup 0} {yields} {omega}{gamma}) < 1.0 x 10{sup -6}; {bar {Beta}}(B {yields} ({rho}/{omega}){gamma}) < 1.2 x 10{sup -6}. These results are in good agreement with the SM predictions. The branching fractions of these decays are then used to constrain the ratio |V{sub td}|/|V{sub ts}|.

Tan, Ping; /Wisconsin U., Madison

2006-03-08T23:59:59.000Z

215

Constraining |V(td)|/|V(ts)| Using Radiative Penguin B -> V(K*/rho/omega)gamma Decays  

Science Conference Proceedings (OSTI)

Exclusive radiative penguin B decays, B {yields} (K*{sup 0}/K*{sup +}) and B {yields} ({rho}/{omega}){gamma}, are flavor-changing neutral-current (FCNC) processes. Studies of these decays are of special interest in testing Standard Model (SM) predictions and searching for other beyond-the-SM FCNC interactions. Using 89 x 10{sup 6} B{bar B} pairs from BABAR, we measure the branching fraction ({Beta}), CP-asymmetry ({Alpha}), and isospin asymmetry ({Delta}{sub 0-}) of B {yields} (K*{sup 0}/K*{sup +}){gamma} as follows: {Beta}(B{sup 0} {yields} K*{sup 0}{gamma}) = 3.92 {+-} 0.20(stat.) {+-} 0.24(syst.); {Beta}(B{sup +} {yields} K*{sup +}{gamma}) = 3.87 {+-} 0.28(stat.) {+-} 0.26(syst.); {Alpha}(B {yields} K*{gamma}) = -0.013 {+-} 0.36(stat.) {+-} 0.10(syst.); {Delta}{sub 0-}(B {yields} K*{gamma}) = 0.050 {+-} 0.045(stat.) {+-} 0.028(syst.) {+-} 0.024(R{sup +/0}). The 90% confidence intervals for the CP-asymmetry and the isospin-asymmetry in the B {yields} K*{gamma} decay are given as: -0.074 Alpha}(B {yields} K*{gamma}) < 0.049, -0.046 < {Delta}{sub 0-} (B {yields} K*{gamma}) < 0.146. We also search for B {yields} ({rho}/{omega}){gamma} decays using 211 x 10{sup 6} B{bar B} pairs from BABAR. No evidence for these decays is found. We set the upper limits at 90% confidence level for these decays: {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) < 0.4 x 10{sup -6}; {Beta}(B{sup +}{yields} {rho}{sup =}{gamma}) < 1.8 x 10{sup -6}; {Beta}(B{sup 0} {yields} {omega}{gamma}) < 1.0 x 10{sup -6}; {bar {Beta}}(B {yields} ({rho}/{omega}){gamma}) < 1.2 x 10{sup -6}. These results are in good agreement with the SM predictions. The branching fractions of these decays are then used to constrain the ratio |V{sub td}|/|V{sub ts}|.

Tan, Ping; /Wisconsin U., Madison

2006-03-08T23:59:59.000Z

216

Evidence for B Semileptonic Decays into the Lambda_c Charm Baryon  

SciTech Connect

We present the first evidence for B semileptonic decays into the charmed baryon {Lambda}{sub c}{sup +} based on 420 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. We measure the relative branching fraction {Beta}({bar B} {yields} {Lambda}{sub c}{sup +} X{ell}{sup -}{bar {nu}}{sub {ell}})/{Beta}({bar B} {yields} {Lambda}{sub c}{sup +}/{bar {Lambda}}{sub c}{sup -}X) = (3.2 {+-} 0.9{sub stat.} {+-} 0.9{sub syst.})%. The significance of the signal including the systematic uncertainty is 4.9 standard deviations.

Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, Antimo; Pappagallo, M.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, Bjarne; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, Robert N.; Jacobsen, R.G.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Banca di Roma /Frascati /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2008-11-05T23:59:59.000Z

217

CDF results on B decays  

SciTech Connect

The authors present recent CDF results on B lifetimes, B meson mass measurements, ratios of branching ratios, and rare decays. In addition, they present the first measurement of time-dependent B{sub d} mixing at CDF. Several results have been updated and a few new ones included since the workshop.

Skarha, J.E. [Johns Hopkins Univ., Baltimore, MD (United States)

1995-05-01T23:59:59.000Z

218

Rare B decays at CDF  

SciTech Connect

The confidence level limits of the CDF search for the B{sub s}{sup 0} and B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -} rare decays and the branching ratio measurement of B{sub s}{sup 0} {yields} D{sub s}{sup +} D{sub s}{sup -} are presented.

Farrington, Sinead M.; /Liverpool U.

2006-10-01T23:59:59.000Z

219

High rate 4. pi. beta. -. gamma. coincidence counting system  

SciTech Connect

A high count rate 4..pi.. ..beta..-..gamma.. coincidence counting system for the determination of absolute disintegration rates of short half-life radionuclides is described. With this system the dead time per pulse is minimized by not stretching any pulses beyond the width necessary to satisfy overlap coincidence requirements. The equations used to correct for the ..beta.., ..gamma.., and coincidence channel dead times and for accidental coincidences are presented but not rigorously developed. Experimental results are presented for a decaying source of /sup 56/Mn initially at 2 x 10/sup 6/ d/s and a set of /sup 60/Co sources of accurately known source strengths varying from 10/sup 3/ to 2 x 10/sup 6/ d/s. A check of the accidental coincidence equation for the case of two independent sources with varying source strengths is presented.

Johnson, L.O.; Gehrke, R.J.

1978-01-01T23:59:59.000Z

220

BECCAV1.0 BETA  

Energy Science and Technology Software Center (OSTI)

002318WKSTN00 Brain-Emulating Cognition and Control Architecture (BECCA) V1.0 beta  http://sourceforge.net/projects/becca 

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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221

The Particle Adventure | Particle decays and annihiliations ...  

NLE Websites -- All DOE Office Websites (Extended Search)

mass in a radioactive decay go? Recall that we said that when uranium decays into thorium and an alpha particle, 0.0046 u of mass appears to have been lost. As Einstein said,...

222

A Global Model of $?^-$-Decay Half-Lives Using Neural Networks  

E-Print Network (OSTI)

Statistical modeling of nuclear data using artificial neural networks (ANNs) and, more recently, support vector machines (SVMs), is providing novel approaches to systematics that are complementary to phenomenological and semi-microscopic theories. We present a global model of $\\beta^-$-decay halflives of the class of nuclei that decay 100% by $\\beta^-$ mode in their ground states. A fully-connected multilayered feed forward network has been trained using the Levenberg-Marquardt algorithm, Bayesian regularization, and cross-validation. The halflife estimates generated by the model are discussed and compared with the available experimental data, with previous results obtained with neural networks, and with estimates coming from traditional global nuclear models. Predictions of the new neural-network model are given for nuclei far from stability, with particular attention to those involved in r-process nucleosynthesis. This study demonstrates that in the framework of the $\\beta^-$-decay problem considered here, global models based on ANNs can at least match the predictive performance of the best conventional global models rooted in nuclear theory. Accordingly, such statistical models can provide a valuable tool for further mapping of the nuclidic chart.

N. Costiris; E. Mavrommatis; K. A. Gernoth; J. W. Clark

2007-01-31T23:59:59.000Z

223

Charged-Higgs-boson search via heavy-top-quark decay at Fermilab Tevatron collider energy  

SciTech Connect

Assuming a top-quark mass of about 150 GeV we analyze the prospects for a charged-Higgs-boson search in top-quark decay at the Fermilab Tevatron upgrade. Universality predicts the relative size of the top decay signal via {ital W} boson in different decay channels, and an observable excess over this prediction can be used as a signature for charged-Higgs-boson production. In the charged-Higgs-boson--fermion coupling scheme suggested by minimal supersymmetry and E{sub 6} string-inspired models one expects to see an observable signal up to a charged-Higgs-boson mass of 100 GeV throughout the allowed range of the coupling parameter tan{beta}. The absence of such a signal would give an unambiguous charged-Higgs-boson mass limit of 100 GeV. This is not possible however in the alternative coupling schemes of two-Higgs-doublet models.

Godbole, R.M. (Department of Physics, University of Bombay, Bombay 400098 (India)); Roy, D.P. (Tata Institute of Fundamental Research, Homi Bhabha Road, Bombay 400005 (India))

1991-06-01T23:59:59.000Z

224

Low radioactivity CaF{sub 2} scintillator crystals for CANDLES  

Science Conference Proceedings (OSTI)

CANDLES is the project to search for neutrinoless double beta (0{nu}{beta}{beta}) decay of {sup 48}Ca by using CaF{sub 2} scintillators. The observation of 0{nu}{beta}{beta} decay will prove the existence of massive Majorana neutrinos. Expected performances and current status of the CANDLES system are described.

Ogawa, I.; Umehara, S.; Ito, G.; Yasuda, K.; Kakubata, H.; Miyashita, M.; Matsuoka, K.; Nomachi, M. [Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Kishimoto, T. [Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047 (Japan); Fushimi, K. [Faculty of Integrated Arts and Science, University of Tokushima, Tokushima 770-8502 (Japan); Hazama, R. [Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8527 (Japan); Ohsumi, H. [Faculty of Culture and Education, Saga University, Saga 840-8502 (Japan); Okada, K. [Department of Computer Science and Engineering, Kyoto San-gyo University, Kyoto 603-8555 (Japan); Tamagawa, Y. [Faculty of Engineering, University of Fukui, Fukui 910-8507 (Japan); Yoshida, S. [Research Center for Neutrino Science, Tohoku University, Sendai, Miyagi 980-8578 (Japan)

2011-04-27T23:59:59.000Z

225

Rare Decays of the $\\eta^{'}$  

E-Print Network (OSTI)

We have searched for the rare decays of the eta prime meson to e+ e- eta, e+ e- pizero, e+ e- gamma, and e mu in hadronic events at the CLEO II detector. The search is conducted on 4.80 fb^-1 of e+ e- collisions at the Cornell Electron Storage Ring. We find no signal in any of these modes, and set 90% confidence level upper limits on their branching fractions of 2.4 X 10^-3, 1.4 X 10^-3, 0.9 X 10^-3, and 4.7 X 10^-4, respectively. We also investigate the Dalitz plot of the common decay of the eta prime to pi+ pi- eta. We fit the matrix element with the Particle Data Group parameterization and find Re(alpha) = -0.021 +- 0.025, where alpha is a linear function of the kinetic energy of the eta.

Briere, R A; Ford, W T; Gritsan, A; Krieg, H; Roy, J D; Smith, J G; Alexander, J P; Baker, R; Bebek, C; Berger, B E; Berkelman, K; Blanc, F; Boisvert, V; Cassel, David G; Dickson, M; Von Dombrowski, S; Drell, P S; Ecklund, K M; Ehrlich, R; Foland, A D; Gaidarev, P B; Galik, R S; Gibbons, L K; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hopman, P I; Jones, C D; Kreinick, D L; Lee, T; Liu, Y; Meyer, T O; Mistry, N B; Ng, C R; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Thayer, J G; Thies, P G; Valant-Spaight, B L; Warburton, A; Avery, P; Lohner, M; Prescott, C; Rubiera, A I; Yelton, J; Zheng, J; Brandenburg, G; Ershov, A; Gao, Y S; Kim, D Y J; Wilson, R; Browder, T E; Li, Y; Rodríguez, J L; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Ernst, J; Gladding, G E; Gollin, G D; Hans, R M; Johnson, E; Karliner, I; Marsh, M A; Palmer, M; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Janicek, R; Patel, P M; Sadoff, A J; Ammar, R; Baringer, P; Bean, A; Besson, D; Coppage, D; Davis, R; Kotov, S A; Kravchenko, I V; Kwak, N; Zhao, X; Anderson, S; Frolov, V V; Kubota, Y; Lee, S J; Mahapatra, R; O'Neill, J J; Poling, R A; Riehle, T; Smith, A; Ahmed, S; Alam, M S; Athar, S B; Jian, L; Ling, L; Mahmood, A H; Saleem, M; Timm, S; Wappler, F; Anastassov, A; Duboscq, J E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Kagan, H; Kass, R; Lorenc, J; Schwarthoff, H; Spencer, M B; Von Törne, E; Zoeller, M M; Richichi, S J; Severini, H; Skubic, P L; Undrus, A E; Bishai, M; Chen, S; Fast, J; Hinson, J W; Lee, J; Menon, N; Miller, D H; Shibata, E I; Shipsey, I P J; Kwon, Y; Lyon, A L; Thorndike, E H; Jessop, C P; Lingel, K; Marsiske, H; Perl, Martin Lewis; Savinov, V; Ugolini, D W; Zhou, X; Coan, T E; Fadeev, V; Korolkov, I Ya; Maravin, Y; Narsky, I; Stroynowski, R; Ye, J; Wlodek, T; Artuso, M; Ayad, R; Dambasuren, E; Kopp, S E; Majumder, G; Moneti, G C; Mountain, R; Schuh, S; Skwarnicki, T; Stone, S; Titov, A; Viehhauser, G; Wang, J C; Wolf, A; Wu, J; Csorna, S E; McLean, K W; Marka, S; Xu, Z; Godang, R; Kinoshita, K; Lai, I C; Pomianowski, P A; Schrenk, S; Bonvicini, G; Cinabro, D; Greene, R; Perera, L P; Zhou, G J; Chan, S; Eigen, G; Lipeles, E; Schmidtler, M; Shapiro, A; Sun, W M; Urheim, J; Weinstein, A J; Würthwein, F; Jaffe, D E; Masek, G E; Paar, H P; Potter, E M; Prell, S; Sharma, V; Asner, D M; Eppich, A; Gronberg, J B; Hill, T S; Lange, D J; Morrison, R J; Nelson, T K; Richman, J D; Roberts, D

2000-01-01T23:59:59.000Z

226

Systematics of {alpha}-decay half-lives around shell closures  

Science Conference Proceedings (OSTI)

We present a systematic calculation of {alpha}-decay half-lives of even-even heavy and superheavy nuclei in the framework of the preformed {alpha} model. The microscopic {alpha}-daughter nuclear interaction potential is calculated by double-folding the density distributions of both {alpha} and daughter nuclei with a realistic effective Michigan three-Yukawa nucleon-nucleon interaction, and the microscopic Coulomb potential is calculated by folding the charge density distributions of the two interacting nuclei. The half-lives are found to be sensitive to the density dependence of the nucleon-nucleon interaction and the implementation of the Bohr-Sommerfeld quantization condition inherent in the Wentzel-Kramers-Brillouin approach. The {alpha}-decay half-lives obtained agree reasonably well with the available experimental data. Moreover, the study has been extended to the newly observed superheavy nuclei. The interplay of closed-shell effects in {alpha}-decay calculations is investigated. The {alpha}-decay calculations give the closed-shell effects of known spherical magicities, Z=82 and N=126, and further predict enhanced stabilities at N=152,162, and 184 for Z=100,108, and 114, owing to the stability of parent nuclei against {alpha} decays. It is worth noting that the aim of this work is not only to reproduce the experimental data better, but also to extend our understanding of {alpha}-decay half-lives around shell closures.

Ismail, M.; Ellithi, A. Y.; Botros, M. M.; Adel, A. [Physics Department, Faculty of Science, Cairo University (Egypt)

2010-02-15T23:59:59.000Z

227

Probing Radiative Solar Neutrinos Decays  

E-Print Network (OSTI)

Motivated by a pilot experiment conducted by F.Vannucci et al. during a solar eclipse, we work out the geometry governing the radiative decays of solar neutrinos. Surprisingly, although a smaller proportion of the photons can be detected, the case of strongly non-degenerate neutrinos brings better limits in terms of the fundamental couplings. We advocate satellite-based experiments to improve the sensitivity.

Frère, J M

1998-01-01T23:59:59.000Z

228

NIST: Marie Curie and the NBS Radium Standards - Decay ...  

Science Conference Proceedings (OSTI)

... Decay schemes from uranium, actinium and thorium series Decay schemes from uranium, actinium and thorium series as given in Frederick ...

2010-10-05T23:59:59.000Z

229

The Particle Adventure | Particle decays and annihiliations ...  

NLE Websites -- All DOE Office Websites (Extended Search)

alphabet: (alpha), (beta), and (gamma). Alpha particles are helium nuclei (2 p, 2 n): Beta particles are speedy electrons: Gamma radiation is a high-energy photon: These three...

230

Recent developments in radiative B decays  

E-Print Network (OSTI)

We report on recent theoretical progress in radiative B decays. We focus on a calculation of logarithmically enhanced QED corrections to the branching ratio and forward-backward asymmetry in the inclusive rare decay anti-B --> X(s) l+ l-, and present the results of a detailed phenomenological analysis. We also report on the calculation of NNLO QCD corrections to the inclusive decay anti-B --> X(s) gamma. As far as exclusive modes are concerned we consider transversity amplitudes and the impact of right-handed currents in the exclusive anti-B --> K^* l+ l- decay. Finally, we state results for exclusive B --> V gamma decays, notably the time-dependent CP-asymmetry in the exclusive B --> K^* gamma decay and its potential to serve as a so-called ``null test'' of the Standard Model, and the extraction of CKM and unitarity triangle parameters from B --> (rho,omega) gamma and B --> K^* gamma decays.

Huber, T

2008-01-01T23:59:59.000Z

231

Double domino driver  

DOE Patents (OSTI)

The double domino driver is fully differential and is optimized for low switching noise and power. The noise behavior and power dissipation is improved by limiting the signal swing. The domino driver consists of a combination of mini drivers, each of which is switched on in two steps. In the first step a voltage equal to a fraction of the supply voltage propagates through the chain of mini drivers and turn them partially on. In the second step the voltage is increased to its maximum value and is made to propagate through the chain, turning the mini drivers completely on. The rise and fall time of the output signal can be increased by adding mini drivers. For a 5 volt supply voltage with 5 mini drivers the switching noise in decreased to levels less than 100 micro volts. The power dissipation with this driver is least as compared to ECL and other logic systems. The double domino driver is useful in communication and VLSI systems.

Vanstraelen, G.F.

1992-01-01T23:59:59.000Z

232

Compositionally Dependent Displacive Transformation from Beta to ...  

Science Conference Proceedings (OSTI)

... quenching from single beta phase field. The present study primarily focuses on possibly a new class of solid-solid mixed mode beta to omega transformation ...

233

Parity Doubling and the S Parameter Below the Conformal Window  

E-Print Network (OSTI)

We describe a lattice simulation of the masses and decay constants of the lowest-lying vector and axial resonances, and the electroweak S parameter, in an SU(3) gauge theory with $N_f = 2$ and 6 fermions in the fundamental representation. The spectrum becomes more parity doubled and the S parameter per electroweak doublet decreases when $N_f$ is increased from 2 to 6, motivating study of these trends as $N_f$ is increased further, toward the critical value for transition from confinement to infrared conformality.

Thomas Appelquist; Ron Babich; Richard C. Brower; Michael Cheng; Michael A. Clark; Saul D. Cohen; George T. Fleming; Joe Kiskis; Meifeng Lin; Ethan T. Neil; James C. Osborn; Claudio Rebbi; David Schaich; Pavlos Vranas

2010-09-29T23:59:59.000Z

234

Low Radioactivity in CANDLES  

SciTech Connect

CANDLES is the project to search for double beta decay of 48Ca by using CaF2 crystals. Double beta decay of 48Ca has the highest Q value among all nuclei whose double beta decay is energetically allowed. This feature makes the study almost background free and becomes important once the study is limited by the backgrounds. We studied double beta decays of 48Ca by using ELEGANTS VI detector system which features CaF2(Eu) crystals. We gave the best limit on the lifetime of neutrino-less double beta decay of 48Ca although further development is vital to reach the neutrino mass of current interest for which CANDLES is designed. In this article we present how CANDLES can achieve low radioactivity, which is the key for the future double beta decay experiment.

Kishimoto, T.; Ogawa, I.; Hazama, R.; Yoshida, S.; Umehara, S.; Matsuoka, K.; Sakai, H.; Yokoyama, D.; Mukaida, K.; Ichihara, K.; Tatewaki, Y.; Kishimoto, K.; Hirano, Y.; Yanagisawa, A.; Ajimura, S. [Department of Physics, Osaka University, Toyonaka, Osaka, 560-0043 (Japan)

2005-09-08T23:59:59.000Z

235

First observation of the Bs->K+K- decay mode, and measurement of the B0 and Bs mesons decay-rates into two-body charmless final states at CDF  

SciTech Connect

The authors searched for decays of the type B{sub (s)}{sup 0} {yields} h{sup +}h{prime}{sup -} (where h, h{prime} = K or {pi}) in a sample corresponding to 180 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected by the upgraded Collider Detector at the Fermilab Tevatron. A total signal of approximately 900 events was reconstructed, and the relative branching fractions ({Beta}) of each decay mode were determined with a likelihood fit.

Tonelli, Diego; /Pisa, Scuola Normale Superiore

2006-11-01T23:59:59.000Z

236

Beta particle monitor for surfaces  

DOE Patents (OSTI)

A beta radiation detector which is capable of reliably detecting beta radiation emitted from a surface. An electrically conductive signal collector is adjustably mounted inside an electrically conductive enclosure which may define a single large opening for placing against a surface. The adjustable mounting of the electrically conductive signal collector can be based on the distance from the surface or on the expected beta energy range. A voltage source is connected to the signal collector through an electrometer or other display means for creating an electric field between the signal collector and the enclosure. Air ions created by the beta radiation are collected and the current produced is indicated on the electrometer or other display means.

MacArthur, Duncan W. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

237

Beta particle monitor for surfaces  

DOE Patents (OSTI)

A beta radiation detector which is capable of reliably detecting beta radiation emitted from a surface. An electrically conductive signal collector is adjustably mounted inside an electrically conductive enclosure which may define a single large opening for placing against a surface. The adjustable mounting of the electrically conductive signal collector can be based on the distance from the surface or on the expected beta energy range. A voltage source is connected to the signal collector through an electrometer or other display means for creating an electric field between the signal collector and the enclosure. Air ions created by the beta radiation are collected and the current produced is indicated on the electrometer or other display means. 2 figs.

MacArthur, D.W.

1997-10-21T23:59:59.000Z

238

Measuring Dirac CP-violating phase with intermediate energy beta beam facility  

E-Print Network (OSTI)

Taking the established nonzero value of $\\theta_{13}$, we study the possibility of extracting the Dirac CP-violating phase by a beta beam facility with a boost factor $100technologies. We find that an antineutrino beam from $^6$He decay with a baseline of L=1300 km has a very promising CP discovery potential using a 500 kton Water Cherenkov (WC) detector. Fortunately this baseline corresponds to the distance between FermiLAB to Sanford underground research facility in South Dakota.

Pouya Bakhti; Yasaman Farzan

2013-07-03T23:59:59.000Z

239

Beta-Gamma Coincidence Counting Using an Yttrium Aluminum Perovskit and Bismuth Germanate Phoswich Scintillator  

SciTech Connect

Abstract– Phoswich detectors (two scintillators attached to the same photomultiplier-tube) have been used in the past to measure either betas or gammas separately but were not used to measure beta-gamma coincidence signatures. These coincidence signatures are very important for the detection of many fission products and are exploited to detect four radioxenon isotopes using the Automated Radioxenon Sampler/Analyzer (ARSA) [1]. Previous PNNL work with a phoswich detector used a commercially available, thin disk of scintillating CaF2(Eu) and a 2” thick NaI(Tl) crystal in a phoswich arrangement. Studies with this detector measured the beta-gamma coincidence signatures from 133Xe, 214Pb and 214Bi [2]. This scintillator combination worked but was not a good match in scintillation light decay times, 940-ns for CaF2(Eu) and 230 ns for NaI(Tl). Additionally, a 6 mm thick quartz window was placed between the NaI(Tl) and the CaF2 to ensure a hermetic seal for the NaI(Tl) crystal . This dead layer significantly reduced the detection probability of the low energy x-rays and gammas that are part of the coincidence signatures for 214Pb, 214Bi and the radioxenons. Further research showed that Yttrium aluminum perovskit (YAP) and bismuth germanate (BGO) have very good scintillation light characteristics and no hermetic seal requirements. The 27-ns scintillation light decay time of YAP and the 300-ns decay time for BGO are a good match between fast and slow light output. The scintillation light output was measured using XIATM digital signal processing readout electronics, and the fast (YAP) and slow (BGO) light components allowed discrimination between the beta and gamma contributions of the radioactive decays. In this paper we discuss the experimental setup and results obtained with this new phoswich detector and the applications beyond radioxenon gas measurements.

McIntyre, Justin I.; Schrom, Brian T.; Aalseth, Craig E.; Cooper, Matthew W.; Hayes, James C.; Heimbigner, Tom R.; Hossbach, Todd W.; Hubbard, Charles W.; Litke, Kevin E.; Ripplinger, Mike D.; Seifert, Carolyn E.; Suarez, Reynold

2006-02-27T23:59:59.000Z

240

Profile-based adaptation for cache decay  

E-Print Network (OSTI)

Cache decay is a leakage-reduction mechanism that puts cache lines that have not been accessed for a specific duration into a lowleakage standby mode. This duration is called the decay interval, and its optimal value varies across applications. This paper describes an adaptation technique that analytically finds the optimal decay interval through profiling, and shows that the most important variables required for finding the optimal decay interval can be estimated using profiling with a reasonable degree of accuracy. Unlike previous methods that attempt to put only ‘dead ’ lines into standby mode, this work explicitly trades off the leakage power saved in putting ‘live ’ lines into standby against its performance and energy costs. It also combines traditional DVS with cache decay using an analysis and obtains results close to what can be obtained with an omniscient choice of per-benchmark optimal decay interval. 1

Karthik Sankaranarayanan

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Decay Study of {sup 257}Rf  

Science Conference Proceedings (OSTI)

The isotope {sup 257}Rf was produced in the fusion-evaporation reaction {sup 208}Pb({sup 50}Ti, n){sup 257}Rf. Reaction products were separated by the Argonne Fragment Mass Analyzer. Radioactive decay and spontaneous fission of {sup 257}Rf and its decay products were investigated. An isomeric state in {sup 257}Rf, with a half-life of 160{sub -31}{sup 42} {mu}S, was discovered by detecting internal conversion electrons followed by alpha decays. It is interpreted as a three-quasiparticle high-K isomer. A second group of internal-conversion electrons which were succeeded by alpha decay, with a half-life of 4.1{sub -1.3}{sup +2.4} s, was observed. These events might originate from the decay of excited states in {sup 257}Lr, populated by electron-capture decay of {sup 257}Rf, or from another isomer in {sup 257}Rf.

Qian, J.; Heinz, A.; Winkler, R. [Yale University, New Haven, CT 06511 (United States); Janssens, R. V. F.; Khoo, T. L.; Seweryniak, D.; Peterson, D.; Back, B. B.; Carpenter, M. P.; Greene, J. P.; Jiang, C. L.; Kondev, F. G.; Lauritsen, T.; Lister, C. J.; Pardo, R. C.; Robinson, A.; Scott, R.; Vondrasek, R.; Wang, X.; Zhu, S. [Argonne National Laboratory, Argonne, IL 60439 (United States)] (and others)

2009-03-04T23:59:59.000Z

242

Beta function and anomalous dimensions  

Science Conference Proceedings (OSTI)

We demonstrate that it is possible to determine the coefficients of an all-orders beta-function linear in the anomalous dimensions using as data the 2-loop coefficients together with the first one of the anomalous dimensions which are universal. The beta function allows us to determine the anomalous dimension of the fermion masses at the infrared fixed point, and the resulting values compare well with the lattice determinations.

Pica, Claudio; Sannino, Francesco [CP3-Origins, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark)

2011-06-01T23:59:59.000Z

243

Reactor Decay Heat in {sup 239}Pu: Solving the {gamma} Discrepancy in the 4-3000-s Cooling Period  

Science Conference Proceedings (OSTI)

The {beta} feeding probability of {sup 102,104,105,106,107}Tc, {sup 105}Mo, and {sup 101}Nb nuclei, which are important contributors to the decay heat in nuclear reactors, has been measured using the total absorption technique. We have coupled for the first time a total absorption spectrometer to a Penning trap in order to obtain sources of very high isobaric purity. Our results solve a significant part of a long-standing discrepancy in the {gamma} component of the decay heat for {sup 239}Pu in the 4-3000 s range.

Algora, A. [IFIC - CSIC-Univ. Valencia, Valencia (Spain); Institute of Nuclear Research, Debrecen (Hungary); Jordan, D.; Tain, J. L.; Rubio, B.; Agramunt, J.; Perez-Cerdan, A. B.; Molina, F.; Caballero, L.; Nacher, E. [IFIC - CSIC-Univ. Valencia, Valencia (Spain); Krasznahorkay, A.; Hunyadi, M. D.; Gulyas, J.; Vitez, A.; Csatlos, M.; Csige, L. [Institute of Nuclear Research, Debrecen (Hungary); Aeysto, J.; Penttilae, H.; Moore, I. D.; Eronen, T.; Jokinen, A. [University of Jyvaeskylae, Jyvaeskylae (Finland)

2010-11-12T23:59:59.000Z

244

New Nuclear And Subnuclear Exotic Decays  

E-Print Network (OSTI)

In this paper new nuclear and subnuclear exotic decays are investigated. Some theoretical problems of the pionic radioactivity, such as fission-like models, applicable to all kind of exotic nuclear and subnuclear decays are presented. The induced nuclear and subnuclear decays are discussed. Moreover, using the recent results on the spontaneous fission half lives T of the heavy nuclei with Z new predictions on the pionic yields in the region of superheavy elements are presented.

D. B. Ion; Reveica Ion-Mihai; M. L. Ion

2007-10-03T23:59:59.000Z

245

R Parity Violating Decays of the Gluino  

E-Print Network (OSTI)

Assuming the lightest supersymmetric particle is the gluino, we treat the decays gluino->quark-antiquark-neutrino and gluino->gluon-neutrino. Such couplings can be induced by the R parity violating quark-squark-lepton interaction which can also be responsible for neutrino masses and mixings. These R parity violating gluino decays have the same final state structure (jets plus missing energy) as previously considered decays into quark-antiquark-photino and gluon-gravitino but with significantly different gluino lifetimes.

L. Clavelli; H. Stremnitzer

2003-08-27T23:59:59.000Z

246

The Particle Adventure | Particle decays and annihiliations ...  

NLE Websites -- All DOE Office Websites (Extended Search)

Particle decays and annihiliations - Electron positron annhiliation When an electron and positron (antielectron) collide at high energy, they can annihilate to produce charm...

247

Spectroscopy of element 115 decay chains  

Science Conference Proceedings (OSTI)

A high-resolution a, X-ray and -ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum fu r Schwerionenforschung. Thirty correlated a-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z = 115. The data includes first candidates of fingerprinting the decay step Mt --> Bh with characteristic X rays. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z > 112. Comprehensive Monte-Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.

Rudolph, Dirk [Lund University, Sweden; Forsberg, U. [Lund University, Sweden; Golubev, P. [Lund University, Sweden; Sarmiento, L. G. [Lund University, Sweden; Yakushev, A. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Andersson, L.-L. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Di Nitto, A. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Duehllmann, Ch. E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Gates, J. M. [Lawrence Berkeley National Laboratory (LBNL); Gregorich, K. E. [Lawrence Berkeley National Laboratory (LBNL); Gross, Carl J [ORNL; Hessberger, F. P. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Herzberg, R.-D [University of Liverpool; Khuyagbaatar, J. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Kratz, J. V. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Rykaczewski, Krzysztof Piotr [ORNL; Schaedel, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Aberg, S. [Lund University, Sweden; Ackermann, D. [GSI-Hemholtzzentrum fur Schwerionenforschung, Darmstadt, Germany; Block, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Brand, H. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Carlsson, B. G. [Lund University, Sweden; Cox, D. [University of Liverpool; Derkx, X. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Eberhardt, K. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Even, J. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Fahlander, C. [Lund University, Sweden; Gerl, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Jaeger, E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kindler, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Krier, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kojouharov, I. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kurz, N. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Lommel, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Mistry, A. [University of Liverpool; Mokry, C. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Nitsche, H. [Lawrence Berkeley National Laboratory (LBNL); Omtvedt, J. P. [Paul Scherrer Institut, Villigen, Switzerland; Papadakis, P. [University of Liverpool; Ragnarsson, I. [Lund University, Sweden; Runke, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Schaffner, H. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Schausten, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Thoerle-Pospiech, P. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Torres, T. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Traut, T. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Trautmann, N. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Tuerler, A. [Paul Scherrer Institut, Villigen, Switzerland; Ward, A. [University of Liverpool; Ward, D. E. [Lund University, Sweden; Wiehl, N. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany

2013-01-01T23:59:59.000Z

248

A Study of Double-Charm and Charm-Strange Baryons inElectron-Positron Annihilations  

SciTech Connect

In this dissertation I describe a study of double-charm and charm-strange baryons based on data collected with the BABAR Detector at the Stanford Linear Accelerator Center. In this study I search for new baryons and make precise measurements of their properties and decay modes. I seek to verify and expand upon double-charm and charm-strange baryon observations made by other experiments. The BABAR Detector is used to measure subatomic particles that are produced at the PEP-II storage rings. I analyze approximately 300 million e+e- {yields} c{bar c} events in a search for the production of double-charm baryons. I search for the double-charm baryons {Xi}{sup +}{sub cc} (containing the quarks ccd) and {Xi}{sup ++}{sub cc} (ccu) in decays to {Lambda}{sup +}{sub c}K{sup -}{pi}{sup +} and {Lambda}{sup +}{sub c}K{sup -}{pi}{sup +}{pi}{sup +}, respectively. No statistically significant signals for their production are found, and upper limits on their production are determined. Statistically significant signals for excited charm-strange baryons are observed with my analysis of approximately 500 million e+e- {yields} c{bar c} events. The charged charm-strange baryons {Xi}{sub c}(2970){sup +}, {Xi}{sub c}(3055){sup +}, {Xi}{sub c}(3123){sup +} are found in decays to {Lambda}{sup +}{sub c}K{sup -}{pi}{sup +}, the same decay mode used in the {Xi}{sup +}{sub cc} search. The neutral charm-strange baryon {Xi}{sub c}(3077){sup 0} is observed in decays to {Lambda}{sup +}{sub c}K{sub 8}{pi}{sup -}. I also search for excited charm-strange baryon decays to {Lambda}{sup +}{sub c}K{sub 8}, {Lambda}{sup +}{sub c}K{sup -}, {Lambda}{sup +}{sub c}K{sub 8}{pi}{sup -}{pi}{sup +}, and {Lambda}{sup +}{sub c}K{sup -}{pi}{sup -}{pi}{sup +}. No significant charm-strange baryon signals a f h these decay modes. For each excited charm-strange baryon state that I observe, I measure its mass, natural width (lifetime), and production rate. The properties of these excited charm-strange baryons and their decay modes provide constraints for phenomenological models of quark interactions through quantum chromodynamics. My discovery of the two new charm-strange baryons {Xi}{sub c}(3055){sup +} and {Xi}{sub c}(3123){sup +} influences our theoretical understanding of charm-strange baryon states.

Edwards, Adam J.; /SLAC

2007-10-15T23:59:59.000Z

249

Double acting bit holder  

DOE Patents (OSTI)

A double acting bit holder that permits bits held in it to be resharpened during cutting action to increase energy efficiency by reducing the amount of small chips produced. The holder consist of: a stationary base portion capable of being fixed to a cutter head of an excavation machine and having an integral extension therefrom with a bore hole therethrough to accommodate a pin shaft; a movable portion coextensive with the base having a pin shaft integrally extending therefrom that is insertable in the bore hole of the base member to permit the moveable portion to rotate about the axis of the pin shaft; a recess in the movable portion of the holder to accommodate a shank of a bit; and a biased spring disposed in adjoining openings in the base and moveable portions of the holder to permit the moveable portion to pivot around the pin shaft during cutting action of a bit fixed in a turret to allow front, mid and back positions of the bit during cutting to lessen creation of small chip amounts and resharpen the bit during excavation use.

Morrell, Roger J. (Blommington, MN); Larson, David A. (Minneapolis, MN); Ruzzi, Peter L. (Eagan, MN)

1994-01-01T23:59:59.000Z

250

Current Status and Results of the NEMO3 Experiment  

Science Conference Proceedings (OSTI)

The NEMO3 detector is mainly devoted to the search for the neutrinoless double beta decay (0???). The detector is located in the Fréjus underground laboratory

J. Jerie; on behalf of the NEMO Collaboration

2007-01-01T23:59:59.000Z

251

High-Efficiency Neutron Detection and Spectroscopy  

Science Conference Proceedings (OSTI)

High-Efficiency Neutron Detection and Spectroscopy. ... such as searches for WIMP dark matter, neutrinoless double beta decay, and solar neutrinos. ...

2013-07-22T23:59:59.000Z

252

Support  

NLE Websites -- All DOE Office Websites (Extended Search)

WIPP Support Double Beta Decay Dark Matter Biology Repository Science Renewable Energy Community, State and Congressional Support for WIPP as a host for Underground Experiments...

253

Research Facilities | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

in Canada, KATRIN direct neutrino mass measurement at Germany and Majorana project for search double beta decay at Pacific Northwest National Laboratory. More information can be...

254

Baryon Resonances in the Double Pion Channel at Jefferson Lab (CEBAF): Experimental and Physical Analysis Status and Perspectives  

E-Print Network (OSTI)

Decay of light quark excited baryons in the double pion channel is discussed, as a particular way of investigating poorly know baryon resonances and searching for "missing states" predicted by quark models. A possible approach to the data analysis is discussed and some preliminary data from the CLAS collaboration at Jefferson Laboratory are presented.

Marco Ripani

1999-02-18T23:59:59.000Z

255

Search for Bbar to Lambda_c+ X l- nu Decays in Events with a Fully Reconstructed B Meson  

SciTech Connect

We present a search for semileptonic B decays to the charmed baryon {Lambda}{sub c}{sup +} based on 420 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. By fully reconstructing the recoiling B in a hadronic decay mode, we reduce non-B backgrounds and determine the flavor of the signal B. We statistically correct the flavor for the effect of the B{sup 0} mixing. We obtain a 90% confidence level upper limit of {Beta}({bar B} {yields} {Lambda}{sub c}{sup +} X{ell}{sup -} {bar {nu}}{sub {ell}})/{Beta}({bar B} {yields} {Lambda}{sub c}{sup +} X) < 3.5%.

Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Tanabe, T.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2012-04-19T23:59:59.000Z

256

Search for CP violation in hyperon decays.  

Science Conference Proceedings (OSTI)

Direct CP violation in nonleptonic hyperon decays can be established by comparing the decays of hyperons and anti-hyperons. For {Xi} decay to {Lambda} {pi} followed by {Lambda} to p{pi}, the proton distribution in the rest frame of Lambda is governed by the product of the decay parameters {alpha}{sub {Xi}} {alpha}{sub {Lambda}}. The asymmetry A{sub {Xi}{Lambda}}, proportional to the difference of {alpha}{sub {Xi}}{alpha}{sub {Lambda}} of the hyperon and anti-hyperon decays, vanishes if CP is conserved. We report on an analysis of a fraction of 1997 and 1999 data collected by the Hyper CP (E871) collaboration during the fixed-target runs at Fermilab. The preliminary measurement of the asymmetry is {Alpha}{sub {Xi}{Lambda}} = [-7 {+-} 12(stat) {+-} 6.2(sys)] x 10{sup -4}, an order of magnitude better than the present limit.

Zyla, Piotr; Chan, A.; Chen, Y.C.; Ho, C.; Teng, P.K.; Choong, W.S.; Gidal, G.; Fu, Y.; Gu, P.; Jones, T.D.; Luk, K.B.; Turko, B.; James, C.; Volk, J.; Felix, J.; Burnstein, R.A.; Chakrovorty, A.; Kaplan, D.M.; Lederman, L.M.; Luebke, W.; Rajaram, D.; Rubin, H.A.; Solomey, N.; Torun, Y.; White, C.G.; White, S.L.; Leros, N.; Perroud, J.P.; Gustafson, H.R.; Longo, M.J.; Lopez, F.; Park H.K.; Clark, K.; Jenkins, M.; Dukes, E.C.; Durandet, C.; Holmstrom, T.; Huang, M.; Lu, L.; Nelson, K.S.

2002-10-25T23:59:59.000Z

257

Variations of decay rates of radio-active elements and their connections with global anisotropy of physical space  

E-Print Network (OSTI)

The analysis of correlations between fluctuations of alpha- and beta-decay rates for different radio-active elements is carried out. These fluctuations exceed significantly errors of measurements in many cases. They have the periodical character and reveal definite spatial directions. We suggest that the observed fluctuations are caused by the unique physical reason connected with the global anisotropy of physical space and by the new force.

Yu. A. Baurov; I. F. Malov

2010-01-29T23:59:59.000Z

258

The decay rate of ocean swell observed by altimeter  

Science Conference Proceedings (OSTI)

Altimeter data from transects across the Southern Ocean is analysed to determine the decay of oceanic swell. The resulting decay rate is shown to be proportional to wave number squared and swell amplitude cubed. Such a decay relationship is ...

I. R. Young; A. V. Babanin; S. Zieger

259

Optimization of the Geometric Beta for the SSR2 Cavities of the Project X  

Science Conference Proceedings (OSTI)

Project X based on the 3 GeV CW superconducting Linac and is currently in the R&D phase. The CW SC Linac starts from a low-energy SCRF section (2.1 - 165 MeV) containing three different types of resonators. HWR f = 162.5 MHz (2.1 - 11 MeV) having beta= 0.11, SSR1 f = 325 MHz (11 - 35 MeV) having beta = 0.21. In this paper we present the analysis that lead to the final design of SSR2 f = 325 MHz cavity (35 - 165 MeV). We present the results of optimization of the geometric beta and the comparison between single, double and triple spoke resonators used in Project X frontend. A {beta} optimization has been carried out for the last spoke cavity section of Project X front end. The optimization process of {beta}{sub opt} for a single spoke resonator family SSR2 shown that {beta}{sub opt} = 0.47 looks better than the previous choice, which is {beta}{sub opt} = 0.4. This change can save some cavities and provide the same final energy for this section, 160 MeV. Single double and triple spoke resonator performances have been compared. The best option is the single spoke resonator SSR2 because the NTTF of a multi-spoke resonator is much narrower than a single one. In the energy range considered (40-160 MeV) the most efficient resonator is the single spoke one.

Solyak, N.; Vostrikov, A.; Yakovlev, V.P.; /Fermilab; Awida, M.H.; Berrutti, P.; Gonin, I.V.; /Fermilab

2012-05-01T23:59:59.000Z

260

Alloy by Double Mechanical Milling  

Science Conference Proceedings (OSTI)

The results show that the morphology of double mechanical milling powder is regular and the TiAl phase and Ti3Al phase were observed in the powders.

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261

Extension of Alpha- and Beta-Decay Systematics of Protactinium Isotopes  

E-Print Network (OSTI)

Hanford Operations Office Idaho Operations Office Iowa State College Knolls Atomic Power Laboratory Los Alamos Mallinckrodt Chemical Works;

Meinke, W. Wayne; Seaborg, Glenn T.

2008-01-01T23:59:59.000Z

262

Princeton University, Physics 311/312 Beta Decay, Page 1 Introduction  

E-Print Network (OSTI)

in the order A, C, D, B (A is a "standby power" switch). Secondly, there is a switch on the magnet power supply

263

The T-Odd R and D Correlations in Beta Decay  

Science Conference Proceedings (OSTI)

... contain the factor ?/? relative to the SU(2)L × U(1) invariant interactions, where ? is the vacuum expectation value of the SM Higgs boson and ? is ...

2005-09-01T23:59:59.000Z

264

Regulatory sequences within DQ. cap alpha. and DQ. beta  

SciTech Connect

The Class II Histocompatibility Antigen DQ is characterized by tissue specific expression, relatively late appearance in development and modulation of expression in response to gamma interferon, phorbol 12-myristate 13-acetate (PMA), and prostaglandins of the E series. They have utilized the sensitive reporter function of chloramphenicol acetyl transferase (CAT) in transient expression assays to screen for the presence of regulatory regions within the DQ..cap alpha.. and DQ..beta.. genes. Two regions have been identified which stimulate CAT transcription in transfected cells. One region includes the first intron of DQ..beta.. and the other region brackets the first exon of DQ/sup 2/. These regions are both tissue specific in their stimulation of CAT transcription i.e., both regions stimulate transcription more effectively in a DQ expressing B cell line (BJAB) than in a DQ negative T cell line (Jurkat). Additionally, the CAT plasmids containing the first intron of DQ..beta.. appear to be gamma interferon responsive. Transfection of these plasmids into BJAB followed by treatment of the cells with gamma interferon for 24 hours results in a doubling of the CAT transcription. This increase is analogous to the endogenous DQ response to gamma interferon. These two regions undoubtedly contribute to the complex regulation of DQ expression.

Sullivan, K.; Peterlin, B.M.

1986-03-05T23:59:59.000Z

265

Double-super-connected digraphs  

Science Conference Proceedings (OSTI)

A strongly connected digraph D is said to be super-connected if every minimum vertex-cut is the out-neighbor or in-neighbor set of a vertex. A strongly connected digraph D is said to be double-super-connected if every minimum vertex-cut is both the out-neighbor ... Keywords: Cartesian product, Double-super-connected, Lexicographic product, Line digraphs, Super-connected

Juan Liu; Jixiang Meng; Zhao Zhang

2010-05-01T23:59:59.000Z

266

Evidence of a new state in $^{11}$Be observed in the $^{11}$Li $?$-decay  

E-Print Network (OSTI)

Coincidences between charged particles emitted in the $\\beta$-decay of $^{11}$Li were observed using highly segmented detectors. The breakup channels involving three particles were studied in full kinematics allowing for the reconstruction of the excitation energy of the $^{11}$Be states participating in the decay. In particular, the contribution of a previously unobserved state at 16.3 MeV in $^{11}$Be has been identified selecting the $\\alpha$ + $^7$He$\\to\\alpha$ + $^6$He+n channel. The angular correlations between the $\\alpha$ particle and the center of mass of the $^6$He+n system favors spin and parity assignment of 3/2$^-$ for this state as well as for the previously known state at 18 MeV.

M. Madurga; M. J. G. Borge; M. Alcorta; L. M. Fraile; H. O. U. Fynbo; B. Jonsond; O. Kirsebom; G. Martinez-Pinedo; T. Nilsson; G. Nyman; A. Perea; A. Poves; K. Riisager; O. Tengblad; E. Tengborn; J. Van der Walle

2009-04-27T23:59:59.000Z

267

Observation of the Inclusive D^{* -} Production in the Decay of Y(1S)  

SciTech Connect

The authors present a study of the inclusive D*{sup {+-}} production in the decay of {Upsilon}(1S) using (98.6 {+-} 0.9) x 10{sup 6} {Upsilon}(2S) mesons collected with the BABAR detector at the {Upsilon}(2S) resonance. Using the decay chain {Upsilon}(2S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(1S), {Upsilon}(1S) {yields} D*{sup {+-}}X, where X is unobserved, they measure the branching fraction {Beta}[{Upsilon}(1S) {yields} D*{sup {+-}}X] = (2.52 {+-} 0.13(stat) {+-} 0.15(syst))% and the D*{sup {+-}} momentum distribution in the rest frame of the {Upsilon}(1S). They find evidence for an excess of D*{sup {+-}} production over the expected rate from the virtual photon annihilation process {Upsilon}(1S) {yields} {gamma}* {yields} c{bar c} {yields} D*{sup {+-}} X.

Aubert, B.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Tico, J.Garra; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G. /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /Rome U. /INFN, Rome /Rome U. /Rome U. /INFN, Rome /Rome U. /INFN, Rome /Rome U. /Rome U. /INFN, Rome /Rome U. /INFN, Rome /Rome U. /Rome U. /INFN, Rome /Rome U. /INFN, Rome /Rome U. /Rome U. /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2009-12-17T23:59:59.000Z

268

Search for Higgs decays to tau lepton pairs at the Tevatron  

E-Print Network (OSTI)

We present a search for neutral supersymmetric Higgs bosons decaying to tau+tau- pairs produced in ppbar collisions at sqrt{s}=1.96 TeV. The data have been collected with the CDF II and D0 detectors at the Tevatron collider at Fermilab (1 fb^-1 of integrated luminosity per experiment). No significant excess above the standard model backgrounds is observed. We set exclusion limits on the Higgs production cross-section times the branching fraction of its decay to tau+tau- pairs for Higgs masses in the range from 90 to 250 GeV/c^2. We also set exclusion limits on MSSM parameters m_A and tan_beta in several benchmark scenarios.

I. Kravchenko; for the CDF; D0 Collaborations

2007-10-26T23:59:59.000Z

269

Search for the neutral MSSM Higgs bosons in the ditau decay channels at CDF Run II  

SciTech Connect

This thesis presents the results on a search for the neutral MSSM Higgs bosons decaying to tau pairs, with least one of these taus decays leptonically. The search was performed with a sample of 1.8 fb{sup -1} of proton-antiproton collisions at {radical}s = 1.96 TeV provided by the Tevatron and collected by CDF Run II. No significant excess over the Standard Model prediction was found and a 95% confidence level exclusion limit have been set on the cross section times branching ratio as a function of the Higgs boson mass. This limit has been translated into the MSSM Higgs sector parameter plane, tan{beta} vs. M{sub A}, for the four different benchmark scenarios.

Cuenca Almenar, Cristobal; /Valencia U., IFIC

2008-04-01T23:59:59.000Z

270

B, D and K Decays  

SciTech Connect

The present report documents the results of Working Group 2: B, D and K decays, of the workshop on Flavor in the Era of the LHC, held at CERN from November 2005 through March 2007. With the advent of the LHC, we will be able to probe New Physics (NP) up to energy scales almost one order of magnitude larger than it has been possible with present accelerator facilities. While direct detection of new particles will be the main avenue to establish the presence of NP at the LHC, indirect searches will provide precious complementary information, since most probably it will not be possible to measure the full spectrum of new particles and their couplings through direct production. In particular, precision measurements and computations in the realm of flavor physics are expected to play a key role in constraining the unknown parameters of the Lagrangian of any NP model emerging from direct searches at the LHC. The aim of Working Group 2 was twofold: on one hand, to provide a coherent, up-to-date picture of the status of flavor physics before the start of the LHC; on the other hand, to initiate activities on the path towards integrating information on NP from high-p{sub T} and flavor data. This report is organized as follows. In Sec. 1, we give an overview of NP models, focusing on a few examples that have been discussed in some detail during the workshop, with a short description of the available computational tools for flavor observables in NP models. Sec. 2 contains a concise discussion of the main theoretical problem in flavor physics: the evaluation of the relevant hadronic matrix elements for weak decays. Sec. 3 contains a detailed discussion of NP effects in a set of flavor observables that we identified as 'benchmark channels' for NP searches. The experimental prospects for flavor physics at future facilities are discussed in Sec. 4. Finally, Sec. 5 contains some assessments on the work done at the workshop and the prospects for future developments.

Artuso, M.; Asner, D.M.; Ball, P.; Baracchini, E.; Bell, G.; Beneke, M.; Berryhill, J.; Bevan, A.; Bigi, I.I.; Blanke, M.; Bobeth, Ch.; Bona, M.; Borzumati, F.; Browder, T.; Buanes, T.; Buchalla, G.; Buchmuller, O.; Buras, A.J.; Burdin, S.; Cassel, D.G.; Cavanaugh, R.; /Syracuse U. /Carleton U. /Durham U., IPPP /Rome U. /INFN, Rome /Karlsruhe U. /RWTH Aachen U. /Fermilab /Queen Mary, U. of London /Notre Dame U. /Munich, Tech. U. /Munich, Max Planck Inst. /Dortmund U. /Annecy, LAPP /ICTP, Trieste /Taiwan, Natl. Central U. /Hawaii U. /Bergen U. /Munich U. /CERN /Liverpool U.

2008-03-07T23:59:59.000Z

271

Search for Lepton Flavour Violating Decays tau- to l- Ks with the BaBar experiment  

SciTech Connect

A search for the lepton flavor violating decays {tau}{sup -} {yields} l{sup -} K{sub S}{sup 0} (l = e or {mu}) has been performed using a data sample corresponding to an integrated luminosity of 469 fb{sup -1}, collected with the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} asymmetric energy collider. No statistically significant signal has been observed in either channel and the estimated upper limits on branching fractions are {Beta}({tau}{sup -} {yields} e{sup -} K{sub S}{sup 0}) < 3.3 x 10{sup -8} and {Beta}({tau}{sup -} {yields} {mu}{sup -}K{sub S}{sup 0}) < 4.0 x 10{sup -8} at 90% confidence level.

Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, R.N.; Jacobsen, R.G.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Karlsruhe U., EKP /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2009-01-06T23:59:59.000Z

272

A Search for the Rare Decay $B\\rightarrow\\gamma\\gamma$  

SciTech Connect

We report the result of a search for the rare decay B{sup 0} {yields} {gamma}{gamma} in 426 fb{sup -1} of data, corresponding to 226 million B{sup 0}{bar B}{sup 0} pairs, collected on the {Upsilon}(4S) resonance at the PEP-II asymmetric-energy e{sup +}e{sup -} collider using the BABAR detector. We use a maximum likelihood fit to extract the signal yield and observe 21{sub -12}{sup +13} signal events with a statistical signficance of 1.9 {sigma}. This corresponds to a branching fraction {Beta}(B{sup 0} {yields} {gamma}{gamma}) = (1.7 {+-} 1.1(stat.) {+-} 0.2(syst.)) x 10{sup -7}. Based on this result, we set a 90% confidence level upper limit of {Beta}(B{sup 0} {yields} {gamma}{gamma}) < 3.2 x 10{sup -7}.

del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-06-02T23:59:59.000Z

273

On the Beta Plane Approximation  

Science Conference Proceedings (OSTI)

The beta plane approximation as it is usually derived suffers from the difficulty that it is only valid if the quasi-geostrophic approximation is made. It is not valid for the underlying momentum and continuity equations. The problem in the ...

W. T. M. Verkley

1990-10-01T23:59:59.000Z

274

$?$ Decay and Isomeric Properties of Neutron-Rich Ca and Sc Isotopes  

E-Print Network (OSTI)

The isomeric and $\\beta$-decay properties of neutron-rich $^{53-57}$Sc and $^{53,54}$Ca nuclei near neutron number $N$=32 are reported, and the low-energy level schemes of $^{53,54,56}$Sc and $^{53-57}$Ti are presented. The low-energy level structures of the $_{21}$Sc isotopes are discussed in terms of the coupling of the valence $1f_{7/2}$ proton to states in the corresponding $_{20}$Ca cores. Implications with respect to the robustness of the $N$=32 subshell closure are discussed, as well as the repercussions for a possible $N$=34 subshell closure.

H. L. Crawford; R. V. F. Janssens; P. F. Mantica; J. S. Berryman; R. Broda; M. P. Carpenter; N. Cieplicka; B. Fornal; G. F. Grinyer; N. Hoteling; B. P. Kay; T. Lauritsen; K. Minamisono; I. Stefanescu; J. B. Stoker; W. B. Walters; S. Zhu

2010-06-30T23:59:59.000Z

275

Low-energy structure of 61Mn populated following $?$ decay of 61Cr  

E-Print Network (OSTI)

$\\beta$ decay of the $^{61}$Cr$_{37}$ ground state has been studied. A new half-life of 233 +/- 11 ms has been deduced, and seven delayed $\\gamma$ rays have been assigned to the daughter, $^{61}$Mn$_{36}$. The low-energy level structure of $^{61}$Mn$_{36}$ is similar to that of the less neutron-rich $^{57,59}$Mn nuclei. The odd-A $_{25}$Mn isotopes follow the systematic trend in the yrast states of the even-even, Z + 1 $_{26}$Fe isotopes, and not that of the Z - 1 $_{24}$Cr isotopes, where a possible onset of collectivity has been suggested to occur already at N = 36.

H. L. Crawford; P. F. Mantica; J. S. Berryman; R. Broda; B. Fornal; C. R. Hoffman; N. Hoteling; R. V. F. Janssens; S. M. Lenzi; J. Pereira; J. B. Stoker; S. L. Tabor; W. B. Walters; X. Wang; S. Zhu

2009-04-29T23:59:59.000Z

276

Simple model for decay of superdeformed nuclei  

E-Print Network (OSTI)

Recent theoretical investigations of the decay mechanism out of a superdeformed nuclear band have yielded qualitatively different results, depending on the relative values of the relevant decay widths. We present a simple two-level model for the dynamics of the tunneling between the superdeformed and normal-deformed bands, which treats decay and tunneling processes on an equal footing. The previous theoretical results are shown to correspond to coherent and incoherent limits of the full tunneling dynamics. Our model accounts for experimental data in both the A~150 mass region, where the tunneling dynamics is coherent, and in the A~190 mass region, where the tunneling dynamics is incoherent.

C. A. Stafford; B. R. Barrett

1999-06-17T23:59:59.000Z

277

delta S = 2 nonleptonic hyperon decays  

E-Print Network (OSTI)

A sensitive search for the rare decays \\Omega^- \\to \\Lambda \\pi^- and \\Xi^0 \\to p \\pi^- has been performed using data from the 1997 run of the HyperCP (Fermilab E871) experiment. Limits on other such processes do not exclude the possibility of observable rates for |\\Delta S| = 2 nonleptonic hyperon decays, provided the decays occur through parity-odd operators. We obtain the branching-fraction limits B(\\Omega^- \\to \\Lambda \\pi^-)< 2.9 x 10^{-6} and B(\\Xi^0 \\to p \\pi^-)< 8.2 x 10^{-6}, both at 90% confidence level.

C. G. White; R. A. Burnstein; A. Chakravorty; A. Chan; Y. C. Chen; W. S. Choong; K. Clark; E. C. Dukes; C. Durandet; J. Felix; G. Gidal; P. Gu; H. R. Gustafson; C. Ho; T. Holmstrom; M. Huang; C. James; C. M. Jenkins; D. M. Kaplan; L. M. Lederman; N. Leros; M. J. Longo; F. Lopez; L. C. Lu; W. Luebke; K. B. Luk; K. S. Nelson; H. K. Park; J. -P. Perroud; D. Rajaram; H. A. Rubin; P. K. Teng; J. Volk; S. L. White; P. Zyla

2005-03-21T23:59:59.000Z

278

delta S = 2 nonleptonic hyperon decays  

E-Print Network (OSTI)

A sensitive search for the rare decays \\Omega^- \\to \\Lambda \\pi^- and \\Xi^0 \\to p \\pi^- has been performed using data from the 1997 run of the HyperCP (Fermilab E871) experiment. Limits on other such processes do not exclude the possibility of observable rates for |\\Delta S| = 2 nonleptonic hyperon decays, provided the decays occur through parity-odd operators. We obtain the branching-fraction limits B(\\Omega^- \\to \\Lambda \\pi^-)< 2.9 x 10^{-6} and B(\\Xi^0 \\to p \\pi^-)< 8.2 x 10^{-6}, both at 90% confidence level.

White, C G; Chakravorty, A; Chan, A; Chen, Y C; Choong, W S; Clark, K; Dukes, E C; Durandet, C; Félix, J; Gidal, G; Gu, P; Gustafson, H R; Ho, C; Holmstrom, T; Huang, M; James, C; Jenkins, C M; Kaplan, D M; Lederman, Leon Max; Leros, Nicolas; Longo, M J; López, F; Lu, L C; Luebke, W; Luk, K B; Nelson, K S; Park, H K; Perroud, Jean-Pierre; Rajaram, D; Rubin, H A; Teng, P K; Volk, J; White, S L; Zyla, P

2005-01-01T23:59:59.000Z

279

Suppressed $B_s$ decays at CDF  

SciTech Connect

We review three recent results of the CDF collaboration on B{sub s}{sup 0} suppressed decays: the first search for CP-violation in the B{sub s}{sup 0} {yields} {phi}{phi} decay, where two CP-violating asymmetries expected to be zero in the Standard Model are measured, and the observation and the branching ratio measurements of B{sub s}{sup 0} {yields} J/{Psi} f{sub 0}(980) and B{sub s}{sup 0} {yields} J/{Psi} K{sup (*)} decays.

Dorigo, Mirco

2011-05-01T23:59:59.000Z

280

B to tau Leptonic and Semileptonic Decays  

Science Conference Proceedings (OSTI)

Decays of B mesons to states involving {tau} leptons can be used as a tool to search for the effects of new physics, such as those involving a charged Higgs boson. The experimental status of the decays B {yields} {tau}{nu} and B {yields} D{sup (*)}{tau}{nu} is discussed, together with limits on new physics effects from current results. Leptonic and semileptonic decays of B mesons into states involving {tau} leptons remain experimentally challenging, but can prove a useful tool for constraining Standard Model parameters, and also offer to constrain the effects of any new physics that may exist including the presence of a charged Higgs boson.

Barrett, M.; /Brunel U.

2011-11-17T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Higgs boson decay to mu mubar gamma  

E-Print Network (OSTI)

The Higgs boson decay, H -> mu mubar gamma, is studied in the Standard Model at the tree and one-loop levels. It is shown that for Higgs boson masses above 110 GeV, the contribution to the radiative width from the one-loop level exceeds the contribution from the tree level, and for Higgs boson masses above 140 GeV, it even exceeds the contribution from the tree level decay H -> mu mubar. We also show that the contributions to the radiative decay width from the interference terms between the tree and one-loop diagrams are negligible.

Ali Abbasabadi; Wayne W. Repko

2000-04-17T23:59:59.000Z

282

Semileptonic B / Bs decays at Belle  

E-Print Network (OSTI)

The Belle experiment at the KEKB asymmetric energy e+e- collider recorded large data sets of both, B and Bs decays. Semileptonic decays B(s) -> X l nu (l = electron or muon) constitute approximately one fifth of the total decay width of B(s) mesons and play an important role in the determination of the CKM matrix elements V_ub and V_cb. Recent results from Belle are presented, including the study of B- -> Ds(*) K l nu, the first measurements of semi-inclusive modes B -> D(*) X l nu and the measurement of the inclusive branching fraction Bf(Bs -> X l nu).

Christian Oswald

2013-05-16T23:59:59.000Z

283

The Particle Adventure | Particle decays and annihiliations | Confusion  

NLE Websites -- All DOE Office Websites (Extended Search)

Confusion about Confusion about decays Confusion about decays Many heavy elements decay into simpler things. But a close observation of these decays reveals several confusing problems. Consider uranium-238 decay. A lump of uranium-238 will decay at a constant rate such that in 4,460,000,000 years -- give or take a few days -- half the uranium will be gone. But there is no way to tell when a specific uranium atom will decay; it could decay five minutes from now, or in ten billion years. Why will an atom decay only according to some probability? Uranium-238 has a mass of 238.0508 atomic mass units (u). It can decay into thorium (234.0436 u) and an alpha particle (4.0026 u). But uranium's mass minus the mass of its decay products is 0.0046 u. Why is there missing mass?

284

SUTTIP V.0.1 BETA  

Energy Science and Technology Software Center (OSTI)

002915WKSTN00 Sandia Unstructured Triangle Tabular Interpolation Package v 0.1 beta  ihttps://software.sandia.gov/ 

285

Alpha decay favoured isotopes of some superheavy nuclei: Spontaneous fission versus alpha decay  

E-Print Network (OSTI)

Spontaneous fission and alpha decay are the main decay modes for superheavy nuclei. The superheavy nuclei which have small alpha decay half-life compared to spontaneous fission half-life will survive fission and can be detected in the laboratory through alpha decay. We have studied the alpha decay half-life and spontaneous half-life of some superheavy elements in the atomic range Z = 100-130. Spontaneous fission half-lives of superheavy nuclei have been calculated using the phenomenological formula and the alpha decay half-lives using Viola-Seaborg-Sobiczewski formula (Sobiczewski et al. 1989), semi empirical relation of Brown (1992) and formula based on generalized liquid drop model proposed by Dasgupta-Schubert and Reyes (2007). The results are reported here.

O. V. Kiren; S. B. Gudennavar; S. G. Bubbly

2013-01-09T23:59:59.000Z

286

Effective field theories for inclusive B decays  

E-Print Network (OSTI)

In this thesis, we study inclusive decays of the B meson. These allow one to determine CKM elements precisely and to search for physics beyond the Standard Model. We use the framework of effective field theories, in ...

Lee, Keith S. M. (Keith Seng Mun)

2006-01-01T23:59:59.000Z

287

The Albedo Decay of Prairie Snows  

Science Conference Proceedings (OSTI)

Daily albedos of snow were measured between November and April, 1969–87, and were analyzed to determine the decay rate between snowfalls. The data essentially represent the snow accumulation season because the analysis was limited to days when ...

D. G. Baker; D. L. Ruschy; D. B. Wall

1990-02-01T23:59:59.000Z

288

Measurement of plasma beta in high-. beta. fusion experiments  

SciTech Connect

The plasma beta on axis of a high-..beta.. plasma column can be determined by combining measurements of the magnetic flux excluded by the plasma column and the plasma luminosity profile. The excluded flux is measured by a balanced loop-probe arrangement consisting of a small magnetic probe outside the discharge tube, which measures the external magnetic field, and a single-turn loop around the discharge tube which senses dphi/ dt inside the tube and is sensitive to the magnetic flux excluded by the plasma. With the signals from the loop and probe nulled without plasma, the integrated difference signal normalized to the integrated probe signal gives the net magnetic flux excluded by the plasma column or the effective area from which flux is completely excluded.

Quinn, W.E.

1978-01-01T23:59:59.000Z

289

Anomalous Radiative Decay of Heavy Higgs Boson  

E-Print Network (OSTI)

The radiative decay width of a heavy Higgs boson $H \\rightarrow W^+W^-\\gamma$ for a {\\it hard} photon is calculated in the Standard Model and its extension with anomalous $\\gamma WW$ couplings. Its dependence on the Higgs mass, the two unknown anomalous couplings, and the photon energy cutoff are studied in detail. We show that this radiative decay of a heavy Higgs is not very sensitive to a wide range of the anomalous couplings compared to the Standard Model result.

Tzu Chiang Yuan

1992-05-27T23:59:59.000Z

290

Passive Core Decay Heat Removal Performance Guideline  

Science Conference Proceedings (OSTI)

Passive decay heat removal systems operate without pumps when normal heat removal systems are not available. Safety is ensured by confirming that an adequate thermal margin is provided to accommodate various operating conditions, design uncertainties, and degradation. Guidelines to ensure adequate thermal performance are provided for three different system configurations.This report introduces utility systems engineers to the design and operation of passive decay heat removal systems and ...

2013-11-26T23:59:59.000Z

291

Rare B Meson Decays at the Tevatron  

SciTech Connect

Rare B meson decays are an excellent probe for beyond the Standard Model physics. Two very sensitive processes are the b {yields} s{mu}{sup +}{mu}{sup -} and B{sub s,d}{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays. We report recent results at a center of mass energy of {radical}s = 1.96 TeV from CDF II using 7 fb{sup -1} at the Fermilab Tevatron Collider.

Hopkins, Walter

2012-01-01T23:59:59.000Z

292

Ambiguity-Free Measurement of cos2beta: Time-Intergrated and Time-Dependent Angular Analyses of B to J/psi K pi  

Science Conference Proceedings (OSTI)

We present results on B {yields} J/{psi} K{pi} decays using e{sup +}e{sup -} annihilation data collected with the BABAR detector at the {Upsilon}(4S) resonance. The detector is located at the PEP-II asymmetric-energy storage ring facility at the Stanford Linear Accelerator Center. Using approximately 88 million B{bar B} pairs, we measure the decay amplitudes for the flavor eigenmodes and observe strong-phase differences indicative of final-state interactions with a significance of 7.6 standard deviations. We use the interference between the K{pi} S-wave and P-wave amplitudes in the region of the K*(892) to resolve the ambiguity in the determination of these strong phases. We then perform an ambiguity-free measurement of cos 2{beta} using the angular and time-dependent asymmetry in B {yields} J/{psi} K*{sup 0} (K{sub S}{sup 0}{pi}{sup 0}) decays. With sin2{beta} fixed at its measured value and cos2{beta} treated as an independent parameter, we find cos 2{beta} = 2.72{sub -0.79}{sup +0.50}(stat) {+-} 0.27(syst), determining the sign of cos 2{beta} to be positive at 86% CL.

Aubert, B.

2004-11-02T23:59:59.000Z

293

Search for pair production of scalar top quarks decaying to a tau lepton and a b quark in 1.96 TeV ppbar collisions  

SciTech Connect

I present the results of a search for pair production of scalar top quarks ({tilde t}{sub 1}) in an R-parity violating supersymmetric scenario using 322 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected by the upgraded Collider Detector at Fermilab. I assume each {tilde t}{sub 1} decays into a {tau} lepton and a b quark, with branching ratio {beta}, and search for final states containing either an electron or a muon from a leptonic {tau} decay, a hadronically decaying {tau} lepton, and two or more jets. Two candidate events pass my final selection criteria, consistent with the expectation from standard model processes. I present upper limits on the cross section times branching ratio squared {sigma}({tilde t}{sub 1}{bar {tilde t}}{sub 1}) x {beta}{sup 2} as a function of the stop mass m({tilde t}{sub 1}). Assuming {beta} = 1, I set a 95% confidence level limit m({tilde t}{sub 1}) > 153 GeV=c{sup 2}. These limits are also fully applicable to the case of a pair produced third generation scalar leptoquark that decays into a {tau} lepton and a b quark.

Khotilovich, Vadim, G.; /Texas A-M

2008-05-01T23:59:59.000Z

294

Compact Beta Particle/Positron Imager for Plant Biology  

Science Conference Proceedings (OSTI)

The 11CO2 tracer is used to facilitate plant biology research towards optimization of plant productivity, biofuel development and carbon sequestration in biomass. Positron emission tomography (PET) imaging has been used to study carbon transport in live plants using 11CO2. Plants typically have very thin leaves resulting in little medium for the emitted positrons to undergo an annihilation event. For the emitted positron from 11C decay approximately 1mm of water equivalent material is needed for positron annihilation. Thus most of the positrons do not annihilate inside the leaf, resulting in limited sensitivity for PET imaging. To address this problem we have developed a compact beta-positive beta-minus particle (BPBM) imager for 11CO2 leaf imaging. The detector is based on a Hamamatsu H8500 position sensitive photomultiplier tube optically coupled via optical grease and a 3mm thick glass plate to a 0.5mm thick Eljin EJ-212 plastic scintillator. The detector is equipped with a flexible arm to allow its placement and orientation on the leaf of the plant of interest while maintaining the leaf's original orientation. We are planning to utilize the imaging device at the Duke University Phytotron to investigate dynamic carbon transport differences between invasive and native species.

Weisenberger, Andrew; Lee, Seung Joon; McKisson, John; Xi, Wenze; Zorn, Carl; Stolin, Alexander; Majewski, Stan; Majewski, Stanislaw; Howell, Calvin; Crowell, Alec

2011-06-01T23:59:59.000Z

295

EIA - Eia.gov BETA  

Gasoline and Diesel Fuel Update (EIA)

Read our feedback policy. Read our feedback policy. Project Feedback Feedback Period Closed This project is closed for further comment, however, comments previously submitted can still be viewed to the right. EIA is currently analyzing the feedback and will be making changes to this web product as needed in preparation for public launch. Suggestions will be implemented depending on the number received, technical or other accessibility issues reported, and the availability of resources to implement any particular suggestion. Thanks for helping us to make EIA's products better! None have been submitted and reviewed for this project. Be the first! Feedback Policy Policy for public posting of feedback submitted during beta testing of EIA experimental web products: User feedback of beta products is moderated. EIA will review all

296

EIA - Eia.gov BETA  

Gasoline and Diesel Fuel Update (EIA)

Feedback Policy Feedback Policy Policy for public posting Feedback Period Closed This project is closed for further comment, however, comments previously submitted can still be viewed to the right. EIA is currently analyzing the feedback and will be making changes to this web product as needed in preparation for public launch. Suggestions will be implemented depending on the number received, technical or other accessibility issues reported, and the availability of resources to implement any particular suggestion. Thanks for helping us to make EIA's products better! of feedback submitted during beta testing of EIA experimental web products: User feedback of beta products is moderated. EIA will review all feedback submissions within one business day. EIA reserves the right to edit feedback for brevity and grammar

297

Decimal System and Double Digits  

NLE Websites -- All DOE Office Websites (Extended Search)

Decimal System and Double Digits Decimal System and Double Digits Name: Ken Status: other Grade: other Country: Canada Date: April 2011 Question: If the origin of the decimal system reflects counting on ten fingers and if zero came into use after the decimal system had been established why did we not create a single symbol for our tenth digit rather than use the double digit 10? If T were to represent the tenth number this would have created a counting system where the number series 1,2...9,T is followed by the same series having a 1 to the left then followed by the same series having a 2 to the left, etc. The T would be the last number in a series of ten single digits rather than be the first number in a series of double digits. The symbol zero would be used only between negative one and positive one because it represents the existence of nothing and, therefore, would have no other function.

298

Search for Hadronic Decays of a Light Higgs Boson in the Radiative Decay ???A?  

E-Print Network (OSTI)

We search for hadronic decays of a light Higgs boson (A?) produced in radiative decays of an ?(2S) or ?(3S) meson, ???A?. The data have been recorded by the BABAR experiment at the ?(3S) and ?(2S) center-of-mass energies ...

Cowan, Ray Franklin

299

Search for MSSM Higgs decaying to tau pairs in ppbar collision at s**(1/2) = 1.96 TeV at CDF  

SciTech Connect

This thesis presents the search for neutral Minimal Supersymmetric extension of Standard Model (MSSM) Higgs bosons decaying to tau pairs where one of the taus decays leptonically, and the other one hadronically. CDF Run II data with L{sub int} = 310 pb{sup -1} are used. There is no evidence of MSSM Higgs existence, which results in the upper limits on {sigma}(p{bar p} {yields} {phi}) x BR({phi} {yields} {tau}{tau}) in m{sub A} range between 115 and 250 GeV. These limits exclude some area in tan {beta} vs m{sub A} parameter space.

Jang, Dongwook; /Rutgers U., Piscataway

2006-05-01T23:59:59.000Z

300

Parametric Decay during HHFW on NSTX  

DOE Green Energy (OSTI)

High Harmonic Fast Wave (HHFW) heating experiments on NSTX have been observed to be accompanied by significant edge ion heating (T{sub i} >> T{sub e}). This heating is found to be anisotropic with T{sub perp} > T{sub par}. Simultaneously, coherent oscillations have been detected with an edge Langmuir probe. The oscillations are consistent with parametric decay of the incident fast wave ({omega} > 13{omega}{sub ci}) into ion Bernstein waves and an unobserved ion-cyclotron quasi-mode. The observation of anisotropic heating is consistent with Bernstein wave damping, and the Bernstein waves should completely damp in the plasma periphery as they propagate toward a cyclotron harmonic resonance. The number of daughter waves is found to increase with rf power, and to increase as the incident wave's toroidal wavelength increases. The frequencies of the daughter wave are separated by the edge ion cyclotron frequency. Theoretical calculations of the threshold for this decay in uniform plasma indicate an extremely small value of incident power should be required to drive the instability. While such decays are commonly observed at lower harmonics in conventional ICRF heating scenarios, they usually do not involve the loss of significant wave power from the pump wave. On NSTX an estimate of the power loss can be found by calculating the minimum power required to support the edge ion heating (presumed to come from the decay Bernstein wave). This calculation indicates at least 20-30% of the incident rf power ends up as decay waves.

J.R. Wilson; S. Bernabei; T. Biewer; S. Diem; J. Hosea; B. LeBlanc; C.K. Phillips; P. Ryan; D.W. Swain

2005-05-13T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

GROSS BETA RADIOACTIVITY OF THE ALGAE AT ENIWETOK ATOLL, 1954-1956  

SciTech Connect

A study was made to determine the amounts of radioactivity in marine algae, water, and lagoon bottom sand collected at Eniwetok Atoll during the period April 1954 to April 1956. The highest levels of beta radioactivity of algae collected after the detonation of a nuclear device (Nectar) were in algae from those islands closest to the site of detonation and in the downwind path of the fallout. With time after detonation, the decline of radioactivity in the algae at Belle Island was faster than can be accounted for on the basis of physical decay alone. In March 1955, algae and bottom sand collected in the deeper waters (20 to 140 feet) of the lagoon, one half to two miles offshore, contained as much or more radioactivity than samples collected in the shallow water near shore. The radioactive decay rates of algae samples collected from Leroy and Henry Islands were greater than those of algae from other islands, indicating that there was less residual contamination from previous detonations at these two islands. Study of the radioactive decay rates of the algae at Belle Island showed that the radioactivity was decaying at a relatively low rate, which became slower with samples collected late in the survey. These observations indicate that the longer-lived isotopes were being taken up by the algae. (auth)

Palumbo, R.F.

1959-08-31T23:59:59.000Z

302

{delta}L=2 hyperon semileptonic decays  

Science Conference Proceedings (OSTI)

We compute the rates of semileptonic B{sub A}{yields}B{sub B}l{sup -}l{sup -} (l=e or {mu}) hyperon transitions in a model where intermediate states involve loops of baryons and a Majorana neutrino. These rates turn out to be well below present experimental bounds and other theoretical estimates. From the experimental upper limit on the {xi}{sup -}{yields}p{mu}{sup -}{mu}{sup -} decay, we derive the bound {<=}22 TeV for the effective Majorana mass of the muon neutrino. Also, an estimate of background contributions for these decays due to the allowed B{sub A}{yields}B{sub B}l{sup -}l{sup -}{nu}{nu} decays is provided.

Barbero, C.; Mariano, A. [Departamento de Fisica, Universidad Nacional, de La Plata, cc 67, 1900 La Plata (Argentina); Li, Ling-Fong [Department of Physics, Carnegie Mellon University, Pittsburg, Pennsylvania 15213 (United States); Castro, G. Lopez [Departamento de Fisica, Cinvestav, Apartado Postal 14-740, 07000 Mexico D.F. (Mexico)

2007-12-01T23:59:59.000Z

303

Factorization in B ---> V gamma decays  

SciTech Connect

The factorization properties of the radiative decays B {yields} V{gamma} are analyzed at leading order in 1/m{sub b} using the soft-collinear effective theory. It is shown that the decay amplitudes can be expressed in terms of a B {yields} V form factor evaluated at q{sup 2} = 0, light-cone distribution amplitudes of the B and V mesons, and calculable hard-scattering kernels. The renormalization-group equations in the effective theory are solved to resum perturbative logarithms of the different scales in the decay process. Phenomenological implications for the B {yields} K*{gamma} branching ratio, isospin asymmetry, and CP asymmetries are discussed, with particular emphasis on possible effects from physics beyond the Standard Model.

Becher, Thomas; /Fermilab; Hill, Richard J.; /SLAC; Neubert, Matthias; /Cornell U., LEPP

2005-03-01T23:59:59.000Z

304

New results for rare muon decays  

Science Conference Proceedings (OSTI)

Branching-ratio limits obtained with the Crystal Box detector are presented for the rare muon decays ..mu.. ..-->.. eee, ..mu.. ..-->.. e..gamma.., and ..mu.. ..-->.. e..gamma gamma... These decays, which violate the conservation of separate lepton-family numbers, are expected to occur in many extensions to the standard model. We found no candidates for the decay ..mu.. ..-->.. eee, yielding an upper limit for the branching ratio of B/sub ..mu..3e/ .. e..gamma.. candidates yields an upper limit of B/sub ..mu..e..gamma../ .. e..gamma gamma.. candidates gives an upper limit of B/sub ..mu..e..gamma gamma../ < 7.2 x 10/sup -11/. These results strengthen the constraints on models that allow transitions between lepton families.

Mischke, R.E.; Bolton, R.D.; Bowman, J.D.; Cooper, M.D.; Frank, J.S.; Hallin, A.L.; Heusi, P.A.; Hoffman, C.M.; Hogan, G.E.; Mariam, F.G.

1986-01-01T23:59:59.000Z

305

Lepton Flavor Violating Decays - Review & Outlook  

E-Print Network (OSTI)

Here I review the status and prospects of experimental investigations into lepton flavor violation (LFV) in charged leptons. Rare LFV processes are naturally expected to occur through loops of TeV scale particles predicted by supersymmetric theories or other models beyond the Standard Model. In contrast to physics of quark flavors that is dominated by the Cabibbo-Kobayashi-Maskawa matrix, LFV in charged leptons is a definitive signal of new physics. Currently active researches are rare tau decay searches at the B factories. The MEG experiment will soon start a sensitive search for the LFV muon decay, mu to e gamma. Prospects for searches at the LHC, a possibility of a fixed target LFV experiment with high energy muons, and a sensitivity of leptonic kaon decays to LFV are also briefly discussed.

Toshinori Mori

2006-05-30T23:59:59.000Z

306

Chiral approach to Phi Radiative Decays  

E-Print Network (OSTI)

(980) and f0(980) according to ? ? f0, a0 + ? and hence are generally considered to provide valuable information about the puzzling light scalar mesons[2] of low energy QCD. The theoretical analysis of this type of decay was initiated by Achasov and Ivanchenko... [3] and followed up by many others [4]. The starting point was the observation that the ? meson decays about 50 per cent of the time into K+K?. Since this final state can easily annihilate to produce either an f0 or a0 together with an emitted photon...

Black, Deirdre; Harada, Masayasu; Shechter, Joseph

2006-01-01T23:59:59.000Z

307

Test of the Conserved Vector Current Hypothesis by beta-ray Angular Distribution Measurement in the Mass-8 System  

E-Print Network (OSTI)

The beta-ray angular correlations for the spin alignments of 8Li and 8B have been observed in order to test the conserved vector current (CVC) hypothesis. The alignment correlation terms were combined with the known beta-alpha-angular correlation terms to determine all the matrix elements contributing to the correlation terms. The weak magnetism term, 7.5\\pm0.2, deduced from the beta-ray correlation terms was consistent with the CVC prediction 7.3\\pm0.2, deduced from the analog-gamma-decay measurement based on the CVC hypothesis. However, there was no consistent CVC prediction for the second-forbidden term associated with the weak vector current. The experimental value for the second-forbidden term was 1.0 \\pm 0.3, while the CVC prediction was 0.1 \\pm 0.4 or 2.1 \\pm 0.5.

T. Sumikama; K. Matsuta; T. Nagatomo; M. Ogura; T. Iwakoshi; Y. Nakashima; H. Fujiwara; M. Fukuda; M. Mihara; K. Minamisono; T. Yamaguchi; T. Minamisono

2011-05-09T23:59:59.000Z

308

Hierarchy in a double braneworld  

Science Conference Proceedings (OSTI)

We show that the hierarchy between the Planck and the weak scales can follow from the tendency of gravitons and fermions to localize at different edges of a thick double wall embedded in an AdS{sub 5} spacetime without reflection symmetry. This double wall is a stable BPS thick-wall solution with two subwalls located at its edges; fermions are coupled to the scalar field through Yukawa interactions, but the lack of reflection symmetry forces them to be localized in one of the subwalls. We show that the graviton zero-mode wave function is suppressed in the fermion edge by an exponential function of the distance between the subwalls, and that the massive modes decouple so that Newtonian gravity is recuperated.

Guerrero, Rommel; Rodriguez, R. Omar [Unidad de Investigacion en Ciencias Matematicas, Universidad Centroccidental Lisandro Alvarado, 400 Barquisimeto (Venezuela); Melfo, Alejandra; Pantoja, Nelson [Centro de Fisica Fundamental, Universidad de Los Andes, Merida (Venezuela)

2006-10-15T23:59:59.000Z

309

Search for Dimuon Decays of a Light Scalar in Radiative Transitions Y(3S) -> gamma A0  

SciTech Connect

The fundamental nature of mass is one of the greatest mysteries in physics. The Higgs mechanism is a theoretically appealing way to account for the different masses of elementary particles and implies the existence of a new, yet unseen particle, the Higgs boson. We search for evidence of a light scalar (e.g. a Higgs boson) in the radiative decays of the narrow {Upsilon}(3S) resonance: {Upsilon}(3S) {yields} {gamma}A{sup 0}, A{sup 0} {yields} {mu}{sup +}{mu}{sup -}. Such an object appears in extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. We find no evidence for such processes in a sample of 122 x 10{sup 6} {Upsilon}(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction product {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} {mu}{sup +}{mu}{sup -}) at (0.25 - 5.2) x 10{sup -6} in the mass range 0.212 {<=} m{sub A{sup 0}} {<=} 9.3 GeV. We also set a limit on the dimuon branching fraction of the {eta}{sub b} meson {Beta}({eta}{sub b} {yields} {mu}{sup +}{mu}{sup -}) < 0.8% at 90% C.L. The results are preliminary.

Aubert, B

2009-06-02T23:59:59.000Z

310

A mass-dependent beta-function  

E-Print Network (OSTI)

Threshold effects related to fermion masses are considered for an all-order beta-function based on a background field momentum subtraction scheme. Far away from all thresholds, the suggested beta-function reduces to the conjectured all-order form inspired by the Novikov-Shifman-Vainshtein-Zakharov beta-function of N=1 supersymmetric gauge theories with a fixed integer number of fermion flavours. At (formally) infinite masses the corresponding pure Yang--Mills beta-function is recovered. We discuss applications to the phase diagram of non-Abelian field theories.

Dietrich, Dennis D

2009-01-01T23:59:59.000Z

311

Introducing the National Library of Energy Beta  

Office of Science (SC) Website

Introducing the National Library of Energy Beta News In the News In Focus 2013 2012 2011 2010 2009 2008 2007 2006 2005 Presentations & Testimony Recovery Act Contact Information...

312

Experiment #7: Magnetic Deflection of Beta Rays  

NLE Websites -- All DOE Office Websites (Extended Search)

of magnetism. Materials Geiger counter Wooden block (to hold the source) Aluminum shield with hole (for Geiger counter) Two cow magnets Magnet holders Sr-90 (beta source)...

313

BECCA V0.1 BETA  

Energy Science and Technology Software Center (OSTI)

002399MLTPL00 Brain-Emulating Cognition and Control Architecture (BECCA) v. 0.2 beta  http://becca.sourceforge.net 

314

Study of the decay asymmetry parameter and CP violation parameter in the Lambdac+ --> Lambda pi+ decay  

E-Print Network (OSTI)

Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement of the weak decay-asymmetry parameter alpha(Lambdac) in Lambdac --> Lambda pi decay. Comparing particle with antiparticle decays, we obtain the first measurement of the CP violation parameter : A = [alpha(Lambdac)+alpha(antiLambda_c)]/[alpha(Lambdac)-alpha(antiLambda_c)]. We obtain alpha(Lambdac)=-0.78+-0.16+-0.13 and A = -0.07+-0.19+-0.12 where errors are statistical and systematic.

J. M. Link

2005-09-28T23:59:59.000Z

315

Search for Lepton-Number Violating Processes in B+ to h- l+ l+ Decays  

SciTech Connect

We have searched for the lepton-number violating processes B{sup +} {yields} h{sup -}{ell}{sup +}{ell}{sup +} with h{sup -} = K{sup -}/{pi}{sup -} and {ell}{sup +} = e{sup +}/{mu}{sup +}, using a sample of 471 {+-} 3 million B{bar B} events collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. We find no evidence for these decays and place 90% confidence level upper limits on their branching fractions B (B{sup +} {yields} {pi}{sup -}e{sup +}e{sup +}) < 2.3 x 10{sup -8}, {Beta}(B{sup +} {yields} K{sup -}e{sup +}e{sup +}) < 3.0 x 10{sup -8}, {Beta}(B{sup +} {yields} {pi}{sup -}{mu}{sup +}{mu}{sup +}) < 10.7 x 10{sup -8}, and {Beta}(B{sup +} {yields} K{sup -}{mu}{sup +}{mu}{sup +}) < 6.7 x 10{sup -8}.

Lees, J.P.

2012-05-17T23:59:59.000Z

316

High-beta plasma research. Task 1: high-beta tokamak research. Task 2: high-beta plasma theory. Annual progress report  

SciTech Connect

A very brief summary of work on high-beta plasma theory and high-beta tokamak research is given. (MOW)

Navratil, G.A.; Chu, C.K.

1986-07-01T23:59:59.000Z

317

Review of K$sup 0$ decays  

SciTech Connect

From meeting of the division of particles and fields; Berkeley, California, USA (13 Aug 1973). A review is given of selected topics in K/sup 0/ decays for which recent results have led to substantial progress and/or cortroversy. (auth)

Nygren, D.R.

1973-08-01T23:59:59.000Z

318

Light Hadron Masses and Decay Constants  

E-Print Network (OSTI)

The extraction of the light hadron spectrum from a first-principle Quantum Chromodynamics approach is a profound application for lattice simulations of Quantum Chromodynamics. This review will cover recent lattice results for the masses and decay constants of the light hadrons. In particular, the applicability of different approaches for the extrapolation towards the physical point will be discussed.

Enno E. Scholz

2009-11-11T23:59:59.000Z

319

Anatomy of neck configuration in fission decay  

E-Print Network (OSTI)

The anatomy of neck configuration in the fission decay of Uranium and Thorium isotopes is investigated in a microscopic study using Relativistic mean field theory. The study includes $^{236}U$ and $^{232}Th$ in the valley of stability and exotic neutron rich isotopes $^{250}U$, $^{256}U$, $^{260}U$, $^{240}Th$, $^{250}Th$, $^{256}Th$ likely to play important role in the r-process nucleosynthesis in stellar evolution. Following the static fission path, the neck configurations are generated and their composition in terms of the number of neutrons and protons are obtained showing the progressive rise in the neutron component with the increase of mass number. Strong correlation between the neutron multiplicity in the fission decay and the number of neutrons in the neck is seen. The maximum neutron-proton ratio is about 5 for $^{260}$U and $^{256}$Th suggestive of the break down of liquid-drop picture and inhibition of the fission decay in still heavier isotopes. Neck as precursor of a new mode of fission decay like multi-fragmentation fission may also be inferred from this study.

S. K. Patra; R. K. Choudhury; L. Satpathy

2010-05-10T23:59:59.000Z

320

Search for the decay B0???  

E-Print Network (OSTI)

We report the result of a search for the rare decay B0??? [B superscript 0???] in 426??fb-1 [fb superscript -1] of data, corresponding to 226×106 B0B? 0 [226 x 10 superscript 6 B superscript 0 B? superscript 0] pairs, ...

Cowan, Ray Franklin

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Decay of a Near-Inertial Wave  

Science Conference Proceedings (OSTI)

The decay of a downward propagating near-inertial wave was observed over four days. During this short period, the energy of the near-inertial wave decreased by 70%. The shear layers produced by the wave were regions of enhanced turbulent ...

Dave Hebert; J. N. Moum

1994-11-01T23:59:59.000Z

322

Fourier Transform of the Stretched Exponential Function: Analytic Error Bounds, Double Exponential Transform, and Open-Source Implementation libkww  

E-Print Network (OSTI)

The C library \\texttt{libkww} provides functions to compute the Kohlrausch-Williams-Watts function, i.e.\\ the Laplace-Fourier transform of the stretched (or compressed) exponential function $\\exp(-t^\\beta)$ for exponents $\\beta$ between 0.1 and 1.9 with sixteen-digits accuracy. Analytic error bounds are derived for the low and high frequency series expansions. For intermediate frequencies the numeric integration is enormously accelerated by using the Ooura-Mori double exponential transformation. The source code is available from the project home page \\url{http://apps.jcns.fz-juelich.de/doku/sc/kww}.

Joachim Wuttke

2009-11-25T23:59:59.000Z

323

Measurement of the Branching Fractions of the Rare Decays B0 to Ds(*)+pi-,B0 to Ds(*)+rho-, and B0 to Ds(*)-K(*)+  

SciTech Connect

The authors report the measurement of the branching fractions of the rare decays B{sup 0} {yields} D{sub s}{sup (*)+} {pi}{sup -}, B{sup 0} {yields} D{sub s}{sup (*)+} {rho}{sup -}, and B{sup 0} {yields} D{sub s}{sup (*)-} K{sup (*)+} in a sample of 381 x 10{sup 6} {Upsilon}(4S) decays into B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. They present evidence for the decay B{sup 0} {yields} D{sub s}{sup -} K*{sup +} and the vector-vector decays B{sup 0} {yields} D{sub s}{sup *+} {rho}{sup -} and B{sup 0} {yields} D{sub s}{sup *-} K{sup *+}, as well as the first measurement of the vector meson polarization in these decays. They also determine the ratios of the CM-suppressed to CKM-favored amplitudes r(D{sup (*)}{pi}) and r(D{sup (*)}{rho}) in decays B{sup 0} {yields} D{sup (*)}{sup {+-}}{pi}{sup {-+}} and B{sup 0} {yields} D{sup (*)}{sup {+-}}{rho}{sup {-+}}, and comment on the prospects for measuring the Cp observable sin(2{beta} + {gamma}).

Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, A.; Pappagallo, M.; /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; Cahn, R.N.; /Energy Sci. Network /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /Frascati /Genoa U. /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /Pisa U. /Princeton U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2008-04-16T23:59:59.000Z

324

Report on the workshop "Decay spectroscopy at CARIBU: advanced fuel cycle applications, nuclear structure and astrophysics". 14-16 April 2011, Argonne National Laboratory, USA.  

SciTech Connect

A workshop on 'Decay Spectroscopy at CARIBU: Advanced Fuel Cycle Applications, Nuclear Structure and Astrophysics' will be held at Argonne National Laboratory on April 14-16, 2011. The aim of the workshop is to discuss opportunities for decay studies at the Californium Rare Isotope Breeder Upgrade (CARIBU) of the ATLAS facility with emphasis on advanced fuel cycle (AFC) applications, nuclear structure and astrophysics research. The workshop will consist of review and contributed talks. Presentations by members of the local groups, outlining the status of relevant in-house projects and availabile equipment, will also be organized. time will also be set aside to discuss and develop working collaborations for future decay studies at CARIBU. Topics of interest include: (1) Decay data of relevance to AFC applications with emphasis on reactor decay heat; (2) Discrete high-resolution gamma-ray spectroscopy following radioactive decya and related topics; (3) Calorimetric studies of neutron-rich fission framgents using Total ABsorption Gamma-Ray Spectrometry (TAGS) technique; (4) Beta-delayed neutron emissions and related topics; and (5) Decay data needs for nuclear astrophysics.

Kondev, F.; Carpenter, M.P.; Chowdhury, P.; Clark, J.A.; Lister, C.J.; Nichols, A.L.; Swewryniak, D. (Nuclear Engineering Division); (Univ. of Massachusetts); (Univ. of Surrey)

2011-10-06T23:59:59.000Z

325

Discovering a Higgs boson decaying to four jets in supersymmetric cascade decays  

SciTech Connect

The Higgs boson may dominantly decay to four light jets through a light pseudoscalar intermediary: h{yields}2{eta}{yields}4j, making reconstruction at the LHC particularly challenging. We explore the phenomenology of such ''buried Higgs'' scenarios in which the primary discovery channel of the Higgs is in cascade decays of superpartners. QCD backgrounds that would otherwise overwhelm the Higgs decay are suppressed by the requirement of high p{sub T} jets and large missing transverse momentum that are the typical signatures of TeV scale supersymmetry. Utilizing jet substructure techniques, we find that for buried Higgses in the 100-120 GeV range, a 5{sigma} discovery can be expected with roughly 10-25 fb{sup -1} of data at E{sub CM}=14 TeV. For lighter Higgs bosons, the signal is contaminated by hadronically decaying W bosons, and discovery remains an unsolved challenge.

Bellazzini, Brando; Csaki, Csaba [Institute for High Energy Phenomenology, Newman Laboratory of Elementary Particle Physics, Cornell University, Ithaca, New York 14853 (United States); Hubisz, Jay; Shao, Jing [201 Physics Building, Syracuse University, Syracuse, New York 13244 (United States)

2011-05-01T23:59:59.000Z

326

Quantum interference terms in nonmesonic weak decay of $?$-hypernuclei within a RPA formalism  

E-Print Network (OSTI)

Single and double coincidence nucleon spectra in the $\\Lambda$-hypernuclei weak decay are evaluated and discussed using a microscopic formalism. Nuclear matter is employed together with the local density approximation which allows us to analyze the $^{12}_{\\Lambda}C$ hypernucleus non-mesonic weak decay. Final state interactions (FSI) are included via the first order (in the nuclear residual interaction) terms to the RPA, where the strong residual interaction is modelled by a Bonn potential. At this level of approximation, these FSI are pure quantum interference terms between the primary decay $(\\Lambda N \\to NN)$ and $(\\Lambda N \\to NN \\to NN)$, where the strong interaction is responsible for the last piece in the second reaction. Also the Pauli exchange contributions are explicitly evaluated. We show that the inclusion of Pauli exchange terms is important. A comparison with data is made. We conclude that the limitations in phase space in the RPA makes this approximation inadequate to reproduce the nucleon spectra. This fact, does not allow us to draw a definite conclusion about the importance of the interference terms.

E. Bauer

2007-07-30T23:59:59.000Z

327

A Statistical Plume Model with First-Order Decay  

Science Conference Proceedings (OSTI)

Many atmospheric contaminants decay or react in the atmosphere. in situations such as the diffusion of radioactive contaminants, certain chemical pollutants and viable microorganisms, a first-order decay rate is considered to be an appropriate ...

Thomas J. Overcamp

1982-11-01T23:59:59.000Z

328

PyDecay/GraphPhys: A Unified Language and Storage System for Particle Decay Process Descriptions  

SciTech Connect

To ease the tasks of Monte Carlo (MC) simulation and event reconstruction (i.e. inferring particle-decay events from experimental data) for long-term BaBar data preservation and analysis, the following software components have been designed: a language ('GraphPhys') for specifying decay processes, common to both simulation and data analysis, allowing arbitrary parameters on particles, decays, and entire processes; an automated visualization tool to show graphically what decays have been specified; and a searchable database storage mechanism for decay specifications. Unlike HepML, a proposed XML standard for HEP metadata, the specification language is designed not for data interchange between computer systems, but rather for direct manipulation by human beings as well as computers. The components are interoperable: the information parsed from files in the specification language can easily be rendered as an image by the visualization package, and conversion between decay representations was implemented. Several proof-of-concept command-line tools were built based on this framework. Applications include building easier and more efficient interfaces to existing analysis tools for current projects (e.g. BaBar/BESII), providing a framework for analyses in future experimental settings (e.g. LHC/SuperB), and outreach programs that involve giving students access to BaBar data and analysis tools to give them a hands-on feel for scientific analysis.

Dunietz, Jesse N.; /MIT /SLAC

2011-06-22T23:59:59.000Z

329

Gamma-ray blind beta particle probe  

DOE Patents (OSTI)

An intra-operative beta particle probe is provided by placing a suitable photomultiplier tube (PMT), micro channel plate (MCP) or other electron multiplier device within a vacuum housing equipped with: 1) an appropriate beta particle permeable window; and 2) electron detection circuitry. Beta particles emitted in the immediate vicinity of the probe window will be received by the electron multiplier device and amplified to produce a detectable signal. Such a device is useful as a gamma insensitive, intra-operative, beta particle probe in surgeries where the patient has been injected with a beta emitting radiopharmaceutical. The method of use of such a device is also described, as is a position sensitive such device.

Weisenberger, Andrew G. (Grafton, VA)

2001-01-01T23:59:59.000Z

330

Measurement of |Vcb| and the Form-Factor Slope in Bbar -> Dlnu Decays in Events Tagged by a Fully Reconstructed B Meson  

SciTech Connect

We present a measurement of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub cb}| and the form-factor slope {rho}{sup 2} in {bar B} {yields} D{ell}{sup -} {bar {nu}}{sub {ell}} decays based on 460 million B{bar B} events recorded at the {Gamma}(4S) resonance with the BABAR detector. {bar B} {yields} D{ell}{sup -} {bar {nu}}{sub {ell}} decays are selected in events in which a hadronic decay of the second B meson is fully reconstructed. We measure the differential decay rate and determine G(1)|V{sub cb}| = (43.0 {+-} 1.9 {+-} 1.4) x 10{sup -3} and {rho}{sup 2} = 1.20 {+-}0.09 {+-} 0.04, where G(1) is the hadronic form factor at the point of zero recoil. We also determine the exclusive branching fractions and find {Beta}(B{sup -} {yields} D{sup 0} {ell}{sup -}{bar {nu}}{sub {ell}}) = (2.31 {+-} 0.08 {+-} 0.09)% and {Beta}(B{sup 0} {yields} D{sup +} {ell}{sup -} {bar {nu}}{sub {ell}}) = (2.23 {+-} 0.11 {+-} 0.11)%.

Aubert, Bernard; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-06-30T23:59:59.000Z

331

Study of the Decay Ds+ to K+K-e+nu  

SciTech Connect

Using 214 fb{sup -1} of data recorded by the BABAR detector at the PEPII electron-positron collider, they study the decay D{sub s}{sup +} {yields} K{sup +}K{sup -}e{sup +}{nu}{sub e}. Except for a small S-wave contribution, the events with K{sup +}K{sup -} masses in the range 1.01-1.03 GeV/c{sup 2} correspond to {phi} mesons. For D{sub s}{sup +} {yields} {phi}e{sup +}{nu}{sub e} decays, they measure the relative normalization of the Lorentz invariant form factors at q{sup 2} = 0, r{sub V} = V(0)/A{sub 1}(0) = 1.849 {+-} 0.060 {+-} 0.095, r{sub 2} = A{sub 2}(0)/A{sub 1}(0) = 0.763 {+-} 0.071 {+-} 0.065 and the pole mass of the axial-vector form factors m{sub A} = (2.28{sub -0.18}{sup +0.23} {+-} 0.18) GeV/c{sup 2}. Within the same K{sup +}K{sup -} mass range, they also measure the relative branching fractions {Beta}(D{sub s}{sup +} {yields} K{sup +}K{sup -}e{sup +}{nu}{sub e})/{Beta}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) - 0.558 {+-} 0.007 {+-} 0.016, from which they obtain the total branching fraction {Beta}(D{sub s}{sup +} {yields} {phi}e{sup +}{nu}{sub e}) = (2.61 {+-} 0.03 {+-} 0.08 {+-} 0.15) x 10{sup -2}. By comparing this value with the predicted decay rate, they extract A{sub 1}(0) = 0.607 {+-} 0.011 {+-} 0.019 {+-} 0.018. The stated uncertainties are statistical, systematic, and from external inputs.

Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, R.N.; Jacobsen, R.G.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /INFN, Naples /Naples U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /Pisa, Scuola Normale Superiore /Princeton U. /INFN, Rome /Rome U. /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2008-07-25T23:59:59.000Z

332

Measurements of Charged Current Lepton Universality and |Vus| using Tau Lepton Decays to e- v v, __- v v, pi- v and K- v  

SciTech Connect

Using 467 fb{sup -1} of e{sup +}e{sup -} annihilation data collected with the BABAR detector, they measure {Beta}({tau}{sup -} {yields} {mu}{sup -}{bar {nu}}{sub {mu}}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} e{sup -} {bar {nu}}{sub e}{nu}{sub {tau}}) = (0.9796 {+-} 0.0016 {+-} 0.0036), {Beta}({tau}{sup -} {yields} {pi}{sup -} {nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} e{sup -}{bar {nu}}{sub e}{nu}{sub {tau}}) = (0.5945 {+-} 0.0014 {+-} 0.0061), and {Beta}({tau}{sup -} {yields} K{sup -}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} e{sup -}{bar {nu}}{sub e}{nu}{sub {tau}}) = (0.03882 {+-} 0.00032 {+-} 0.00057), where the uncertainties are statistical and systematic, respectively. From these precision {tau} measurements, they test the Standard Model assumption of {mu}-e and {tau}-{mu} charge current lepton universality and provide determinations of |V{sub us}| experimentally independent of the decay of a kaon.

Aubert, Bernard; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-06-30T23:59:59.000Z

333

Reheating induced by competing decay modes  

SciTech Connect

We address the problem of studying the decay of the inflaton field {phi} to another scalar field {chi} through parametric resonance in the case of a coupling that involves several decay modes. This amounts to the presence of extra harmonic terms in the perturbation of the {chi} field dynamics. For the case of two frequencies we compute the geometry of the resonance regions, which is significantly altered due to the presence of noncuspidal resonance regions associated to higher harmonics and to the emergence of instability 'pockets'. We discuss the effect of this change in the efficiency of the energy transfer process for the simplest case of a coupling given by a combination of the two interaction terms of homogeneous degree usually considered in the literature. We find that the presence of higher harmonics has limited cosmological implications.

Charters, T. [Departamento de Engenharia Mecanica/Area Cientifica de Matematica, Instituto Superior de Engenharia de Lisboa, Rua Conselheiro Emidio Navarro, 1, P-1949-014 Lisbon, Portugal and Centro de Fisica Teorica e Computacional da Universidade de Lisboa, Avenida Professor Gama Pinto 2, P-1649-003 Lisbon (Portugal); Nunes, A.; Mimoso, J. P. [Departamento de Fisica, Faculdade de Ciencias da Universidade de Lisboa, Centro de Fisica Teorica e Computacional da Universidade de Lisboa, Avenida Professor Gama Pinto 2, P-1649-003 Lisbon (Portugal)

2008-10-15T23:59:59.000Z

334

Time reversal invariance in polarized neutron decay  

SciTech Connect

An experiment to measure the time reversal invariance violating (T-violating) triple correlation (D) in the decay of free polarized neutrons has been developed. The detector design incorporates a detector geometry that provides a significant improvement in the sensitivity over that used in the most sensitive of previous experiments. A prototype detector was tested in measurements with a cold neutron beam. Data resulting from the tests are presented. A detailed calculation of systematic effects has been performed and new diagnostic techniques that allow these effects to be measured have been developed. As the result of this work, a new experiment is under way that will improve the sensitivity to D to 3 {times} 10{sup {minus}4} or better. With higher neutron flux a statistical sensitivity of the order 3 {times} 10{sup {minus}5} is ultimately expected. The decay of free polarized neutrons (n {yields} p + e + {bar v}{sub e}) is used to search for T-violation by measuring the triple correlation of the neutron spin polarization, and the electron and proton momenta ({sigma}{sub n} {center_dot} p{sub p} {times} p{sub e}). This correlation changes sign under reversal of the motion. Since final state effects in neutron decay are small, a nonzero coefficient, D, of this correlation indicates the violation of time reversal invariance. D is measured by comparing the numbers of coincidences in electron and proton detectors arranged symmetrically about a longitudinally polarized neutron beam. Particular care must be taken to eliminate residual asymmetries in the detectors or beam as these can lead to significant false effects. The Standard Model predicts negligible T-violating effects in neutron decay. Extensions to the Standard Model include new interactions some of which include CP-violating components. Some of these make first order contributions to D.

Wasserman, E.G.

1994-03-01T23:59:59.000Z

335

Nuclear decay data for selected radionuclides  

SciTech Connect

Contained in this report are tabulations of the atomic and nuclear radiations emitted by 194 radioactive nuclides. The nuclei included comprise most of those currently of interest in medical practice or research, health physics, industry, nuclear power, environmental impact studies, and as reference standards. Listed in tabular form are recommended values for half-lives, energies, intensities (probabilities per decay), and equilibrium absorbed-dose constants for each of the atomic and nuclear radiations emitted by these radioactive atoms. (auth)

Martin, M.J. (ed.)

1976-03-01T23:59:59.000Z

336

Proton decay matrix elements from lattice QCD  

Science Conference Proceedings (OSTI)

We report on the calculation of the matrix elements of nucleon to pseudoscalar decay through a three quark operator, a part of the low-energy, four-fermion, baryon-number-violating operator originating from grand unified theories. The direct calculation of the form factors using domain-wall fermions on the lattice, incorporating the u, d and s sea-quarks effects yields the results with all the relevant systematic uncertainties controlled for the first time.

Aoki, Yasumichi; Shintani, Eigo [Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan); RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973 (United States); Collaboration: RBC Collaboration; UKQCD Collaboration

2012-07-27T23:59:59.000Z

337

Suppression of Exponential Electronic Decay in a Charged Environment  

Science Conference Proceedings (OSTI)

Inner-shell ionization of atoms and molecules leads to the creation of highly excited ionic states that often decay by electron emission. The dynamics of the decay is usually assumed to be exponential and the process is characterized by a decay rate. Here we show that in a multiply ionized cluster created by interaction with a high-intensity free-electron laser (FEL) radiation, trapping of the emitted electron by the neighboring ions changes the character of the decay dynamics qualitatively to the extent that it can become oscillatory instead of exponential. Implications of the predicted effect on Coster-Kronig and interatomic Coulombic decay processes induced by FELs are investigated.

Averbukh, Vitali [Max Planck Institute for the Physics of Complex Systems, Noethnitzer Strasse 38, D-01187 Dresden (Germany); Saalmann, Ulf; Rost, Jan Michael [Max Planck Institute for the Physics of Complex Systems, Noethnitzer Strasse 38, D-01187 Dresden (Germany); Max Planck Advanced Study Group at the Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg (Germany)

2010-06-11T23:59:59.000Z

338

Method for conversion of .beta.-hydroxy carbonyl compounds ...  

A process is disclosed for conversion of salts of .beta.-hydroxy carbonyl compounds forming useful conversion products including, e.g., .alpha.,.beta.-unsaturated ...

339

National Library of Energy beta: A New Search Engine Facilitating...  

Office of Scientific and Technical Information (OSTI)

National Library of Energy beta: A New Search Engine Facilitating Access to DOE Info National Library of Energy, Beta OSTI has launched the Department of Energy (DOE) National...

340

The Quotient of the beta-Weibull Distribution.  

E-Print Network (OSTI)

??A new class of distributions recently developed involves the logit of the beta distribution. Among this class of distributions are, the beta-Normal (Eugene et al.… (more)

Mdziniso, Nonhle Channon

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
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341

Double parton interactions as a background to associated HW production at the Tevatron  

SciTech Connect

In this paper we study events with W+jets final state, produced in double parton (DP) interactions, as a background to the associated Higgs boson (H) and W production, with H {yields} b{bar b} decay, at the Tevatron. We have found that the event yield from the DP background can be quite sizable, what necessitates a choice of selection criteria to separate the HW and DP production processes. We suggest a set of variables sensitive to the kinematics of DP and HW events. We show that these variables, being used as an input to the artificial neural network, allow one to significantly improve a sensitivity to the Higgs boson production.

Bandurin, Dmitry; Golovanov, Georgy; Skachkov, Nikolai

2010-11-01T23:59:59.000Z

342

Delayed Nickel Decay in Gamma Ray Bursts  

E-Print Network (OSTI)

Recently observed emission lines in the X-ray afterglow of gamma ray bursts suggest that iron group elements are either produced in the gamma ray burst, or are present nearby. If this material is the product of a thermonuclear burn, then such material would be expected to be rich in Nickel-56. If the nickel remains partially ionized, this prevents the electron capture reaction normally associated with the decay of Nickel-56, dramatically increasing the decay timescale. Here we examine the consequences of rapid ejection of a fraction of a solar mass of iron group material from the center of a collapsar/hypernova. The exact rate of decay then depends on the details of the ionization and therefore the ejection process. Future observations of iron, nickel and cobalt lines can be used to diagnose the origin of these elements and to better understand the astrophysical site of gamma ray bursts. In this model, the X-ray lines of these iron-group elements could be detected in suspected hypernovae that did not produce an observable gamma ray burst due to beaming.

G. C. McLaughlin; R. A. M. J. Wijers

2002-05-19T23:59:59.000Z

343

Search for Exclusive Charmless Hadronic B Decays  

E-Print Network (OSTI)

We have searched for several two-body charmless hadronic decays of B mesons. These final states include K and with both charged and neutral kaons and pions; K , Kae, and ae; and OEX s , where X s = K; K , or OE. The data used in this analysis consist of 2:0 fb \\Gamma1 taken on the \\Upsilon(4S ) with the CLEO-II detector at the Cornell Electron Storage Ring (CESR). This data set includes 2.2 million BB pairs, allowing us to place upper limits on these branching ratios in the range from 10 \\Gamma4 to 10 \\Gamma5 . Permanent address: University of Hawaii at Manoa y Permanent address: INP, Novosibirsk, Russia 2 I. INTRODUCTION The decays of B-mesons to two charmless hadrons can proceed via a b ! u tree-level spectator diagram (Figure 1a), or via a b ! sg one-loop "penguin-diagram" (Figure 1b) and to a lesser extent, via the CKM-suppressed b ! dg penguin diagram. Although rare decays can also proceed via b ! u internal, color-suppressed diagrams (Figure 1c), b ! u exch...

Gronberg Kutschke Menary; Ichep Ref; Gsl Cleo Conf; Search Exclusive; Charmless Hadronic; B Decays; S. Menary; S. Nakanishi; C. Qiao

1994-01-01T23:59:59.000Z

344

A Double Smoothing Technique for Constrained Convex ...  

E-Print Network (OSTI)

In this paper, we propose an efficient approach for solving a class of convex opti- ... accelerate our scheme, we introduce a novel double smoothing technique ...

345

Double perovskite catalysts for oxidative coupling  

DOE Patents (OSTI)

Alkali metal doped double perovskites containing manganese and at least one of cobalt, iron and nickel are useful in the oxidative coupling of alkane to higher hydrocarbons.

Campbell, K.D.

1991-01-01T23:59:59.000Z

346

Double Patenting--One Patent per Invention  

Science Conference Proceedings (OSTI)

Double Patenting—One Patent per Invention. Arnold B. Silverman. Patent claims recite the scope of protection provided by a patent. The Patent Statute ...

347

Kernridge project does double duty  

SciTech Connect

The huge volume of steam that Kernridge Oil Co. generates to increase production of heavy crude oil from California's South Belridge field may do double duty. The company, a subsidiary of Shell Oil Co., is in the planning stages with a cogeneration project that would produce enough electricity to meet the electric needs of a community of more than 200,000 people. Meanwhile, Kernridge continues to exceed projections used in the acquisition assessment for the former Belridge Oil Co. properties which the Kernridge parent, Shell, bought in December 1979. The company formed Kernridge early in 1980 to operate the former Belridge properties. Since taking over, Kernridge has pursued development aggressively and has increased production to 65,000 bopd from the previous owner's 42,000 bopd.

Not Available

1981-10-01T23:59:59.000Z

348

Measurement of the neutron $\\beta$-asymmetry parameter $A_0$ with ultracold neutrons  

E-Print Network (OSTI)

We present a detailed report of a measurement of the neutron $\\beta$-asymmetry parameter $A_0$, the parity-violating angular correlation between the neutron spin and the decay electron momentum, performed with polarized ultracold neutrons (UCN). UCN were extracted from a pulsed spallation solid deuterium source and polarized via transport through a 7-T magnetic field. The polarized UCN were then transported through an adiabatic-fast-passage spin-flipper field region, prior to storage in a cylindrical decay volume situated within a 1-T $2 \\times 2\\pi$ solenoidal spectrometer. The asymmetry was extracted from measurements of the decay electrons in multiwire proportional chamber and plastic scintillator detector packages located on both ends of the spectrometer. From an analysis of data acquired during runs in 2008 and 2009, we report $A_0 = -0.11966 \\pm 0.00089_{-0.00140} ^{+0.00123}$, from which we extract a value for the ratio of the weak axial-vector and vector coupling constants of the nucleon, $\\lambda = g...

Plaster, B; Back, H O; Bowles, T J; Broussard, L J; Carr, R; Clayton, S; Currie, S; Filippone, B W; Garcia, A; Geltenbort, P; Hickerson, K P; Hoagland, J; Hogan, G E; Hona, B; Holley, A T; Ito, T M; Liu, C -Y; Liu, J; Makela, M; Mammei, R R; Martin, J W; Melconian, D; Mendenhall, M P; Morris, C L; Mortensen, R; Pattie, R W; Jr.,; Galvan, A Perez; Pitt, M L; Ramsey, J C; Russell, R; Saunders, A; Schmid, R; Seestrom, S J; Sjue, S; Sondheim, W E; Tatar, E; Tipton, B; Vogelaar, R B; VornDick, B; Wrede, C; Xu, Y P; Yan, H; Young, A R; Yuan, J

2012-01-01T23:59:59.000Z

349

Search for Charged Higgs Boson Decays of the Top Quark Using Hadronic tau Decays  

SciTech Connect

We present the result of a search for charged Higgs boson decays of the top quark, produced in p{bar p} collisions at {radical}s = 1.8 TeV. When the charged Higgs boson is heavy and decays to a {tau} lepton, which subsequently decays hadronically, the resulting events have a unique signature: large missing transverse energy and the low-charged-multiplicity {tau}. Data collected in 1992 and 1993 at the Collider Detector at Fermilab, corresponding to 18.7 {+-} 0.7 pb{sup -1}, exclude new regions of combined top quark and charged Higgs boson mass, in extensions to the standard model with two Higgs doublets.

Abe, F.

1996-01-01T23:59:59.000Z

350

Rossby Wave Propagation an Beta-Planes  

Science Conference Proceedings (OSTI)

The numerical modeling of stratospheric, quasi-geostrophic Rossby wave propagation on a beta-plane channel is examined to determine how wave propagation is affected by the use of low horizontal (spectral) resolution. This study considers time ...

Donal O'Sullivan

1988-01-01T23:59:59.000Z

351

Barotropic Vortex Evolution on a Beta Plane  

Science Conference Proceedings (OSTI)

A barotropic, primitive equation (shallow water) model is used on the beta plane to investigate the influence of divergence, total relative angular momentum (RAM) and advective nonlinearities on the evolution of a hurricane-like vortex. The ...

Lloyd J. Shapiro; Katsuyuki V. Ooyama

1990-01-01T23:59:59.000Z

352

Improvements to the on-line mass separator, RAMA, and the beta-delayed charged-particle emission of proton-rich sd shell nuclei  

SciTech Connect

To overcome the extreme difficulties encountered in the experimental decay studies of proton drip line nuclei, several techniques have been utilized, including a helium-jet transport system, particle identification detectors and mass separation. Improvements to the ion source/extraction region of the He-jet coupled on-line Recoil Atom Mass Analyzer (RAMA) and its target/ion source coupling resulted in significant increases in RAMA efficiencies and its mass resolution, as well as reductions in the overall transit time. At the 88-Inch Cyclotron at LBNL, the decays of {sup 31}Cl, {sup 27}P and {sup 28}P, with half-lives of 150 msec, 260 msec and 270.3 msec, respectively, were examined using a he-jet and low-energy gas {Delta}E-gas {Delta}E-silicon E detector telescopes. Total beta-delayed proton branches of 0.3% and 0.07% in {sup 31}Cl and {sub 27}P, respectively, were estimated. Several proton peaks that had been previously assigned to the decay of {sup 31}Cl were shown to be from the decay of {sup 25}Si. In {sup 27}P, two proton groups at 459 {+-} 14 keV and 610 {+-} 11 keV, with intensities of 7 {+-} 3% and 92 {+-} 4% relative to the main (100%) group were discovered. The Gamow-Teller component of the preceding beta-decay of each observed proton transition was compared to results from shell model calculations. Finally, a new proton transition was identified, following the {beta}-decay of {sup 28}P, at 1,444 {+-} 12 keV with a 1.7 {+-} 0.5% relative intensity to the 100% group. Using similar low-energy detector telescopes and the mass separator TISOL at TRIUMF, the 109 msec and 173 msec activities, {sup 17}Ne and {sup 33}Ar, were studied. A new proton group with energy 729 {+-} 15 keV was observed following the beta-decay of {sup 17}Ne. Several discrepancies between earlier works as to the energies, intensities and assignments of several proton transitions from {sup 17}Ne and {sup 33}Ar were resolved.

Ognibene, T.J. [Lawrence Berkeley National Lab., CA (United States). Nuclear Science Div.

1996-03-01T23:59:59.000Z

353

Method for treating beta-spodumene ceramics  

DOE Patents (OSTI)

A vapor-phase method for treating a beta-spodumene ceramic article to achieve a substitution of exchangeable hydrogen ions for the lithium present in the beta-spodumene crystals, wherein a barrier between the ceramic article and the source of exchangeable hydrogen ions is maintained in order to prevent lithium contamination of the hydrogen ion source and to generate highly recoverable lithium salts, is provided.

Day, J. Paul (Big Flats, NY); Hickman, David L. (Big Flats, NY)

1994-09-27T23:59:59.000Z

354

Beta/alpha continuous air monitor  

DOE Patents (OSTI)

A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinquishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts. 7 figs.

Becker, G.K.; Martz, D.E.

1988-06-27T23:59:59.000Z

355

Improved double planar probe data analysis technique  

Science Conference Proceedings (OSTI)

Plasma electron number density and ion number density in a dc multidipole weakly collisional Ar plasma are measured with a single planar Langmuir probe and a double planar probe, respectively. A factor of two discrepancy between the two density measurements is resolved by applying Sheridan's empirical formula [T. E. Sheridan, Phys. Plasmas 7, 3084 (2000)] for sheath expansion to the double probe data.

Ghim, Young-chul; Hershkowitz, Noah [Department of Engineering Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2009-03-15T23:59:59.000Z

356

Double bevel construction of a diamond anvil  

DOE Patents (OSTI)

A double or multiple bevel culet geometry is used on a diamond anvil in a high pressure cell apparatus to provide increased sample pressure and stability for a given force applied to the diamond tables. Double or multiple bevel culet geometries can also be used for sapphire or other hard crystal anvils. Pressures up to and above 5 Megabars can be reached. 8 figs.

Moss, W.C.

1988-10-11T23:59:59.000Z

357

Engineering aspects of disruption current decay  

SciTech Connect

Engineering features associated with the configuration of a tokamak can affect the amount of energy that produces melting and damage to the limiters or internal wall surfaces as the result of a major disruption. During the current decay period of a major thermal disruption, the energy that can damage a wall or limiter comes from the external magnetic field. By providing a good conducting torus near the plasma and increasing the plasma circuit resistance, this magnetic energy (transferred by way of the plasma circuit) can be minimized. This report addresses engineering design features to reduce the energy deposited on the inner torus surface that produces melting of the structures.

Murray, J.G.

1983-11-01T23:59:59.000Z

358

Looking for meson molecules in B decays  

SciTech Connect

We use the QCD sum rule approach to study a {eta} Prime - {pi} molecular current. We consider an isovector-scalar I{sup G}J{sup PC} = 1{sup -}0{sup ++} molecular current. We work at leading order in {alpha}{sub s} and consider the contributions of condensates up to dimension six. We obtain a mass around 1.1 GeV, consistent with a loosely bound state. We discuss the possibility of observing this molecular state in a B threebody hadronic decay.

Nielsen, Marina; Navarra, Fernando S. [Instituto de Fisica, Universidade de Sao Paulo, C.P. 66318, 05389-970 Sao Paulo, SP (Brazil); Bediaga, Ignacio [Centro Brasileiro de Pesquisas Fisicas, Rua Xavier Sigaud 150, 22290-180 Rio de Janeiro, RJ (Brazil)

2013-05-06T23:59:59.000Z

359

Spectroscopy and lifetime measurements of states in {sup 76}Kr populated in {sup 76}Rb decay  

SciTech Connect

The properties of the excited states of {sup 76}Kr, populated in the decay of {sup 76}Rb produced at ISOLDE isotopic separator, have been investigated by using K-conversion electron, {gamma}-ray, and {gamma}-{gamma} coincidence measurements. The lifetimes of several levels have been measured by means of the advanced time-delayed {beta}{gamma}{gamma}(t) method. The identification of 19 new levels and 55 transitions and the information deduced on spin and/or parity of the observed states from K-conversion coefficients, log ft values and decay properties have led to an improved knowledge of the level scheme. In particular, six 1{sup -} states have been definitely identified and J{sup {pi}}=2{sup -} has been assigned to the 2227 keV level, on which a band proposed to have negative-parity and even-spin had been previously observed. The strengths of the E0 and E2 transitions deexciting the 0{sub 2}{sup +} and 0{sub 3}{sup +} states (the latter is here identified with the state at 1598 keV) have been measured. The experimental data concerning the 0{sub 2}{sup +} state have been analyzed in a simple two states mixing model and in the framework of the proton-neutron interacting boson model.

Giannatiempo, A.; Perego, A.; Sona, P.; Nannini, A.; Mach, H.; Fogelberg, B.; Borge, M.J.G.; Tengblad, O.; Fraile, L.M.; Aas, A.J.; Gulda, K. [Dipartimento di Fisica, Universita di Firenze and Istituto Nazionale di Fisica Nucleare, Florence (Italy); Istituto Nazionale di Fisica Nucleare, Florence (Italy); Department of Radiation Sciences, University of Uppsala, S-75121 Uppsala (Sweden); Instituto 'Estructura de la Materia' Consejo Superior de Investigaciones Cientificas, Madrid (Spain); McKinsey and Company, Oslo (Norway); Ministry of Economic Affairs and Labour Department of Innovation, Warsaw (Poland)

2005-10-01T23:59:59.000Z

360

Reliability Estimation for Double Containment Piping  

Science Conference Proceedings (OSTI)

Double walled or double containment piping is considered for use in the ITER international project and other next-generation fusion device designs to provide an extra barrier for tritium gas and other radioactive materials. The extra barrier improves confinement of these materials and enhances safety of the facility. This paper describes some of the design challenges in designing double containment piping systems. There is also a brief review of a few operating experiences of double walled piping used with hazardous chemicals in different industries. This paper recommends approaches for the reliability analyst to use to quantify leakage from a double containment piping system in conceptual and more advanced designs. The paper also cites quantitative data that can be used to support such reliability analyses.

L. Cadwallader; T. Pinna

2012-08-01T23:59:59.000Z

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361

Measurements of Branching Fractions and CP Asymmetries and Studies of Angular Distributions for B to phi phi K Decays  

SciTech Connect

We present branching fraction and CP asymmetry measurements as well as angular studies of B {yields} {phi}{phi}K decays using 464 x 10{sup 6} B{bar B} events collected by the BABAR experiment. The branching fractions are measured in the {phi}{phi} invariant mass range below the {eta}{sub c} resonance (m{sub {phi}{phi}} < 2.85 GeV). We find {Beta}(B{sup +} {yields} {phi}{phi}K{sup +}) = (5.6 {+-} 0.5 {+-} 0.3) x 10{sup -6} and {Beta}(B{sup 0} {yields} {phi}{phi}K{sup 0}) = (4.5 {+-} 0.8 {+-} 0.3) x 10{sup -6}, where the first uncertaintiy is statistical and the second systematic. The measured direct CP asymmetries for the B{sup {+-}} decays are A{sub CP} = -0.10 {+-} 0.08 {+-} 0.02 below the {eta}{sub c} threshold (m{sub {phi}{phi}} < 2.85 GeV) and A{sub CP} = 0.09 {+-} 0.10 {+-} 0.02 in the {eta}{sub c} resonance region (m{sub {phi}{phi}} in [2.94,3.02] GeV). Angular distributions are consistent with J{sub P} = 0{sup -} in the {eta}{sub c} resonance region and favor J{sup P} = 0{sup +} below the {eta}{sub c} resonance.

Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-15T23:59:59.000Z

362

Study of B to X \\gamma Decays and Determination of |V_{td}/V_{ts}|  

SciTech Connect

Using a sample of 471 million B{bar B} events collected with the BABAR detector, we study the sum of seven exclusive final states B {yields} X{sub s(d){gamma}}, where X{sub s(d)} is a strange (non-strange) hadronic system with a mass of up to 2.0 GeV/c{sup 2}. After correcting for unobserved decay modes, we obtain a branching fraction for b {yields} d{gamma} of (9.2 {+-} 2.0(stat.) {+-} 2.3(syst.)) x 10{sup -6} in this mass range, and a branching fraction for b {yields} s{gamma} of (23.0 {+-} 0.8(stat.) {+-} 3.0(syst.)) x 10{sup -5} in the same mass range. We find {Beta}(b{yields}d{gamma})/{Beta}(b{yields}s{gamma}) = 0.040 {+-} 0.009(stat.) {+-} 0.010(syst.), from which we determine |V{sub td}/V{sub ts}| = 0.199 {+-} 0.022(stat.) {+-} 0.024(syst.) {+-} 0.002(th.).

del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-22T23:59:59.000Z

363

Evidence for an excess of B to D(*) Tau Nu decays  

SciTech Connect

Based on the full BABAR data sample, we report improved measurements of the ratios R(D{sup (*)}) = {Beta}({bar B} {yields} D{sup (*)} {tau}{sup -}{bar {nu}}{sub {tau}})/{Beta}({bar B} {yields} D{sup (*)} {ell}{sup -}{bar {nu}}{sub {ell}}), where {ell} is either e or {mu}. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D) = 0.440 {+-} 0.058 {+-} 0.042 and R(D*) = 0.332 {+-} 0.024 {+-} 0.018, which exceed the Standard Model expectations by 2.0{sigma} and 2.7{sigma}, respectively. Taken together, our results disagree with these expectations at the 3.4{sigma} level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model. We also report the observation of the decay {bar B} {yields} D{tau}{sup -} {bar {nu}}{sub {tau}}, with a significance of 6.8{sigma}.

Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Palano, A.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; /Bergen U.; Brown, David Nathan; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /LBL, Berkeley /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; So, R.Y.; /British Columbia U.; Khan, A.; /Brunel U.; Blinov, V.E.; /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U., Comp. Sci. Dept. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U.; /more authors..

2012-10-09T23:59:59.000Z

364

Theoretical Review on CP Violation in Rare B decays  

E-Print Network (OSTI)

We discuss several issues related to direct CP violation in rare $B$ meson decays. We review the use of CP asymmetries in extracting information of strong and weak phases, how the experimental data fit into the overall picture, and the current status of the $K \\pi$ puzzle. We also examine the flavor symmetry assumption using closely related decay modes and extract the weak phase $\\gamma$ from certain $B \\to K^* \\pi$ and $\\rho K$ decays.

Chiang, Cheng-Wei

2008-01-01T23:59:59.000Z

365

Theoretical Review on CP Violation in Rare B decays  

E-Print Network (OSTI)

We discuss several issues related to direct CP violation in rare $B$ meson decays. We review the use of CP asymmetries in extracting information of strong and weak phases, how the experimental data fit into the overall picture, and the current status of the $K \\pi$ puzzle. We also examine the flavor symmetry assumption using closely related decay modes and extract the weak phase $\\gamma$ from certain $B \\to K^* \\pi$ and $\\rho K$ decays.

Cheng-Wei Chiang

2008-08-09T23:59:59.000Z

366

Decaying Higgs Fields and Cosmological Dark Energy  

E-Print Network (OSTI)

The observed dark energy in the universe might give particles inertial mass. We investigate one realization of this idea, that the dark energy field might be a decayed scalar component of a supermultiplet field in the early universe that creates inertial mass through spontaneous symmetry breaking, e.g. a Higgs field. To investigate this possibility, the cosmological Friedmann equation of energy balance is augmented in a standard way to incorporate a minimally coupled cosmological Higgs. For epochs where the expansion of the universe is driven by matter and radiation and not the scalar field, the observed hidden nature of the Higgs field can be codified into a single differential equation that we call the "hidden higgs" condition. The resulting differential equation is solved for the time dependant scalar field and a simple and interesting solution is found analytically. Such a Higgs field decays from Planck scale energies rapidly and approximately exponentially from onset, leaving only the initially negligible constant term of the potential as a final cosmological constant. Such evolution replaces the hierarchy problem with the problem of explaining why such evolution is physically justified.

Robert J. Nemiroff; Bijunath Patla

2004-09-27T23:59:59.000Z

367

Proton decay matrix elements on the lattice  

E-Print Network (OSTI)

Hadronic matrix elements of proton decay are essential ingredients to bridge the grand unification theory to low energy observables like proton lifetime. In this paper we non-perturbatively calculate the matrix elements, relevant for the process of a nucleon decaying into a pseudoscalar meson and an anti-lepton through generic baryon number violating four-fermi operators. Lattice QCD with 2+1 flavor dynamical domain-wall fermions with the {\\it direct} method, which is direct measurement of matrix element from three-point function without chiral perturbation theory, are used for this study to have good control over the lattice discretization error, operator renormalization, and chiral extrapolation. The relevant form factors for possible transition process from an initial proton or neutron to a final pion or kaon induced by all types of three quark operators are obtained through three-point functions of (nucleon)-(three-quark operator)-(meson) with physical kinematics. In this study all the relevant systematic uncertainties of the form factors are taken into account for the first time, and the total error is found to be the range 30%-40% for $\\pi$ and 20%-40% for $K$ final states.

Y. Aoki; E. Shintani; A. Soni

2013-04-28T23:59:59.000Z

368

Physicists Challenge Reports of Accelerated Decay of Nuclear...  

NLE Websites -- All DOE Office Websites (Extended Search)

Photon Source at Argonne, appear in the August 13 edition of Physical Review Letters. Nuclear isomers include excited states of nuclei that electromagnetically decay slowly...

369

Decays of J/psi (3100) to baryon final states  

SciTech Connect

We present results for the decays of psi(3100) into baryon and hyperon final states. The sample studied here consists of 1.3 million produced psi decays. The decays into nonstrange baryons agree well with currently established results, but with better statistics. In addition, significant resonance formation in multibody final states is observed. The decay psi ..-->.. anti pp..gamma.., the first direct photon decay of the psi involving baryons in the final state, is presented and the theoretical implications of the decays are briefly explored. Several new decays of the psi involving strange baryons are explored, including the first observations of three body final states involving hyperons. The I-spin symmetry of the strong decay psi ..-->.. baryons has clearly been observed. The reduced matrix elements for psi ..-->.. B anti B are presented for final states of different SU(3) content. The B/sub 8/ anti B/sub 8/ results are in excellent agreement with the psi being an SU(3) singlet as are the results for psi ..-->.. B/sub 10/ anti B/sub 10/. We present the first evidence for the SU(3) violating decays of the type psi ..-->.. B/sub 8/ anti B/sub 10/ + c.c.. Angular distributions for psi ..-->.. B/sub 8/ anti B/sub 8/ are presented and compared with theoretical predictions. Statistics are limited, but the data tends to prefer other than a 1 + Cos/sup 2/theta distribution.

Eaton, M.W.

1982-05-01T23:59:59.000Z

370

Study of the decay $\\Lambda$sub(c) --> $\\Lambda$ l$^{+}$ $\  

E-Print Network (OSTI)

Using the CLEO II detector at CESR, we observe 500 \\Lambda l^+ pairs consistent with the semileptonic decay \\Lambda_c \\to \\Lambda l^+ \

Bergfeld, T; Gollin, G; Ong, B; Palmer, M; Selen, M; Thaler, J J; Sadoff, A J; Ammar, R; Ball, S; Baringer, P; Bean, A; Besson, D; Coppage, D; Copty, N; Davis, R; Hancock, N; Kelly, M; Kwak, N; Lam, H; Kubota, Y; Lattery, M; Nelson, J K; Patton, S; Perticone, D; Poling, R; Savinov, V; Schrenk, S; Wang, R; Alam, M S; Kim, I J; Nemati, B; O'Neill, J J; Severini, H; Sun, C R; Zoeller, M M; Crawford, G; Daubenmier, C M; Fulton, R; Fujino, D; Gan, K K; Honscheid, K; Kagan, H; Kass, R; Lee, J; Malchow, R; Morrow, F; Skovpen, Y; Sung, M; White, C; Butler, F; Fu, X; Kalbfleisch, G; Ross, W R; Skubic, P L; Snow, J; Wang, P L; Wood, M; Brown, D N; Fast, J; McIlwain, R L; Miao, T; Miller, D H; Modesitt, M; Payne, D; Shibata, E I; Shipsey, I P J; Wang, P N; Battle, M; Ernst, J; Kwon, Y; Roberts, S; Thorndike, E H; Wang, C H; Dominick, J; Lambrecht, M; Sanghera, S; Shelkov, V; Skwarnicki, T; Stroynowski, R; Volobuev, I P; Wei, G; Zadorozhny, P; Artuso, M; Goldberg, M; He, D; Horwitz, N; Kennett, R; Mountain, R; Moneti, G C; Muheim, F; Mukhin, Y; Playfer, S; Rozen, Y; Stone, S; Thulasidas, M; Vasseur, G; Zhu, G; Bartelt, J; Csorna, S E; Egyed, Z; Jain, V; Kinoshita, K; Edwards, K W; Ogg, M; Britton, D I; Hyatt, E R F; MacFarlane, D B; Patel, P M; Akerib, D S; Barish, B; Chadha, M; Chan, S; Cowen, D F; Eigen, G; Miller, J S; O'Grady, C; Urheim, J; Weinstein, A J; Acosta, D; Athanas, M; Masek, G; Paar, H P; Gronberg, J; Kutschke, R; Menary, S; Morrison, R J; Nakanishi, S; Nelson, H N; Nelson, T K; Qiao, C; Richman, J D; Ryd, A; Tajima, H; Schmidt, D; Sperka, D; Witherell, M S; Procario, M; Balest, R; Cho, K; Daoudi, M; Ford, W T; Johnson, D R; Lingel, K; Lohner, M; Rankin, P; Smith, J G; Alexander, J P; Bebek, C; Berkelman, K; Bloom, K; Browder, T E; Cassel, D G; Cho, H A; Coffman, D M; Drell, P S; Ehrlich, R; García-Sciveres, M; Geiser, B; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Jones, C D; Jones, S L; Kandaswamy, J; Katayama, N; Kim, P C; Kreinick, D L; Ludwig, G S; Masui, J; Mevissen, J; Mistry, N B; Ng, C R; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Salman, S; Sapper, M; Würthwein, F; Avery, P; Freyberger, A; Rodríguez, J; Stephens, R; Yang, S; Yelton, J; Cinabro, D; Henderson, S; Liu, T; Saulnier, M; Wilson, R; Yamamoto, H

1994-01-01T23:59:59.000Z

371

Decay processes in an inhomogeneous time-varying plasma  

SciTech Connect

The decay of a homogeneous pump field in an inhomogeneous time-varying plasma into a plasma wave and an ion-acoustic wave is considered theoretically.

Andreev, A.A.; Fedorov, V.I.

1977-12-01T23:59:59.000Z

372

Radioactive-nuclide decay data in science and technology  

SciTech Connect

The scope of ENDF/B has recently been expanded to include radioactive- nuclide decay data. In this paper, the content and organization of the decay data which are included in ENDF/B are presented and discussed. The application of decay data in a wide variety of nuclear-related activities is illustrated by a number of examples. Two items pointed up by the ENDF/B decay-data compilation effort are treated: the identification of deficiencies in the data; and the importance of a radioactive-nuclide metrology effort oriented toward supplying these needs in a systematic fashion. (3 figures, 1 table) (auth)

Reich, C.W.; Helmer, R.G.

1975-01-01T23:59:59.000Z

373

Optical detection of atmospheric 238U decay products  

Science Conference Proceedings (OSTI)

Current and proposed programs involving aerial survey of uranium resources require remote sensing of 238U decay products with high sensitivity. In this paper

Jerry E. Solomon

1977-01-01T23:59:59.000Z

374

Inhomogeneous dynamic nuclear polarization and suppression of electron-polarization decay in a quantum dot  

E-Print Network (OSTI)

We investigate the dynamic nuclear polarization process by frequently injecting polarized electron spins into a quantum dot. Due to the suppression of the direct dipolar and indirect electron-mediated nuclear spin interactions, by the frequently injected electron spins, the analytical predictions under the independent spin approximation agree well with quantum numerical simulations. Our results show that the acquired nuclear polarization is highly inhomogeneous, proportional to the square of the local electron-nuclear hyperfine interaction constant, if the injection frequency is high. Utilizing the inhomogeneously polarized nuclear spins as an initial state, we further show that the electron-polarization decay time can be extended 100 times even at a relatively low nuclear polarization (<20%), without much suppression of the fluctuation of the Overhauser field. Our results lay the foundation for future investigations of the effect of DNP in more complex spin systems, such as double quantum dots and nitrogen vacancy centers in diamonds.

Na Wu; Wenkui Ding; Anqi Shi; Wenxian Zhang

2013-03-04T23:59:59.000Z

375

Application of nuclear density functionals to lepton number violating weak processes  

Science Conference Proceedings (OSTI)

We present an application of energy density functional methods with the Gogny interaction to the calculation of nuclear matrix elements (NME) for neutrinoless double beta decay and double electron capture. Beyond mean field effects have been included by particle number and angular momentum restoration and shape mixing within the generator coordinate method (GCM) framework. We analyze in detail the NME for {sup 116}Cd nucleus which is one of the most promising candidates to detect neutrinoless double beta decay.

Rodriguez, Tomas R.; Martinez-Pinedo, Gabriel [Technische Universitaet Darmstadt, Magdalenenstr. 12, D-64289, Darmstadt (Germany) and GSI Helmholtzzentrum fuer Schwerionenforschung, Plankstr. 1, D-64291 Darmstadt (Germany)

2012-10-20T23:59:59.000Z

376

Invisible Higgs Boson Decay into Massive Neutrinos of 4th Generation  

E-Print Network (OSTI)

Results from several recent experiments provide inderect evidences in the favor of existence of a 4th generation neutrino. Such a neutrino of mass about 50 GeV is compatible with current physical and astrophysical constraints and well motivated in the framework of superstring phenomenology. If sufficiently stable the existence of such a neutrino leads to the drastic change of Higgs boson physics: for a wide range of Higgs boson masses the dominant mode of Higgs boson decay is invisible and the branching ratios for the most promising modes of Higgs boson search are significantly reduced. The proper strategy of Higgs boson searches in such a framework is discussed. It is shown that in the same framework the absence of a signal in the search for invisible Higgs boson decay at LEP means either that the mass of Higgs is greater than 113.5 GeV or that the mass difference between the Higgs mass and doubled neutrino mass is small.

K. Belotsky; D. Fargion; M. Khlopov; R. Konoplich; K. Shibaev

2002-10-09T23:59:59.000Z

377

Chiral Suppression of Scalar Glueball Decay  

DOE Green Energy (OSTI)

Because glueballs are SU(3){sub Flavor} singlets, they are expected to couple equally to u,d, and s quarks, so that equal coupling strengths to {pi}{sup +}{pi}{sup -} and K{sup +}K{sup -} are predicted. However, we show that chiral symmetry implies the scalar glueball amplitude for G{sub 0} {yields} {bar q}q is proportional to the quark mass, so that mixing with {bar s}s mesons is enhanced and decays to K{sup +}K{sup -} are favored over {pi}{sup +}{pi}{sup -}. Together with evidence from lattice calculations and from experiment, this supports the hypothesis that f{sub 0}(1710) is the ground state scalar glueball.

Chanowitz, Michael S.

2005-06-10T23:59:59.000Z

378

Search for invisibly decaying Higgs bosons  

E-Print Network (OSTI)

In the last running years, the four Large Electron Positron collider (LEP) experiments collected a combined luminosity of almost 2.5 fb ?1 at ? s ? 189 GeV. This data was searched for invisibly decaying Higgs bosons produced in association with a Z boson. The channels with electrons, muons and hadrons were investigated. None of the experiments sees hints for the production of such an invisible Higgs boson, thus each of them sets an individual lower limit on the mass at 95 % confidence level. The highest of the four limits is set at 114.1 GeV. The combination of the final results has yet to be done and will increase the reach of the search. PoS(HEP2005)329

André Georg Holzner; André Georg Holzner

2005-01-01T23:59:59.000Z

379

Spectrum and decays of kaonic hydrogen  

E-Print Network (OSTI)

By using the non-relativistic effective Lagrangian approach to bound states, a complete expression for the isospin-breaking corrections to the energy levels and the decay widths of kaonic hydrogen is obtained up-to-and-including O(alpha,m_d-m_u) in QCD. It is demonstrated that, although the leading-order corrections at O(alpha^{1/2},(m_d-m_u)^{1/2}) emerging due to the unitarity cusp, are huge, they can be expressed solely in terms of the KN S-wave scattering lengths. Consequently, at leading order, it is possible to derive parameter-free modified Deser-type relations, which can be used to extract the scattering lengths from the hadronic atom data.

Ulf-G. Meissner; Udit Raha; Akaki Rusetsky

2004-02-25T23:59:59.000Z

380

T-686: IBM Tivoli Integrated Portal Java Double Literal Denial...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

686: IBM Tivoli Integrated Portal Java Double Literal Denial of Service Vulnerability T-686: IBM Tivoli Integrated Portal Java Double Literal Denial of Service Vulnerability August...

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Why DNA is a double helix  

NLE Websites -- All DOE Office Websites (Extended Search)

Guest14 Location: NA Country: NA Date: NA Question: Why is DNA in a double-helix shape? Replies: The why questions are always the worst. Why is anything the way it is? The...

382

Double layer capacitors : automotive applications and modeling  

E-Print Network (OSTI)

This thesis documents the work on the modeling of double layer capacitors (DLCs) and the validation of the modeling procedure. Several experiments were conducted to subject the device under test to a variety of ...

New, David Allen, 1976-

2004-01-01T23:59:59.000Z

383

D-branes and doubled geometry  

E-Print Network (OSTI)

We define the open string version of the nonlinear sigma model on doubled geometry introduced by Hull and Reid-Edwards, and derive its boundary conditions. These conditions include the restriction of D-branes to maximally isotropic submanifolds as well as a compatibility condition with the Lie algebra structure on the doubled space. We demonstrate a systematic method to derive and classify D-branes from the boundary conditions, in terms of embeddings both in the doubled geometry and in the physical target space. We apply it to the doubled three-torus with constant H-flux and find D0-, D1-, and D2-branes, which we verify transform consistently under T-dualities mapping the system to f-, Q- and R-flux backgrounds.

Cecilia Albertsson; Tetsuji Kimura; Ronald A. Reid-Edwards

2008-06-11T23:59:59.000Z

384

Method of producing .beta.-spodumene bodies  

DOE Patents (OSTI)

Beta-spodumene bodies and method of preparing the bodies that involves providing a uniform plastic batch of inorganic raw materials, organic binder, and vehicle, wherein the inorganic raw materials are composed of, in percent by weight, about 75% to 95% minerals, and about 5% to 25% glass. The batch is formed into a green body that is fired to produce a body composed substantially of beta-spodumene, and having a thermal expansion coefficient of <10.times.10.sup.-7 /.degree.C.(0-800.degree. C.), and a strength of .gtoreq.4 Ksi.

Chyung, Kenneth (Painted Post, NY); Day, J. Paul (Big Flats, NY); Holleran, Louis M. (Big Flats, NY); Olszewski, Anthony R. (Bath, NY)

1999-01-01T23:59:59.000Z

385

On the Decay of Tropical Cyclone Winds Crossing Narrow Landmasses  

Science Conference Proceedings (OSTI)

A method is developed to adjust the Kaplan and DeMaria tropical cyclone inland wind decay model for storms that move over narrow landmasses. The basic assumption that the wind speed decay rate after landfall is proportional to the wind speed is ...

Mark DeMaria; John A. Knaff; John Kaplan

2006-03-01T23:59:59.000Z

386

Reach in All Hadronic Stop Decays: A Snowmass White Paper  

E-Print Network (OSTI)

We study the discovery prospects for stops which decay to a top and a light neutralino. We consider fully hadronic decays of the tops and present an estimate for the reach at various future collider runs. Our results are summarized in Table 1.

Stolarski, Daniel

2013-01-01T23:59:59.000Z

387

Reach in All Hadronic Stop Decays: A Snowmass White Paper  

E-Print Network (OSTI)

We study the discovery prospects for stops which decay to a top and a light neutralino. We consider fully hadronic decays of the tops and present an estimate for the reach at various future collider runs. Our results are summarized in Table 1.

Daniel Stolarski

2013-09-06T23:59:59.000Z

388

Baryonic Decays of Charmonium - a Window on Internal Baryon Structure  

E-Print Network (OSTI)

The baryonic decays of $J/ \\psi$ provide a new way to study the internal structure of baryons. A simple diquark model applied to the calculation of the $\\bar{B}B$ decay cross-sections is compared with the ordinary constituent quark model. Various models also give different predictions for the rates involving the $N^{\\ast}(1440)$ resonance in the final state.

A. Cieply

2004-12-03T23:59:59.000Z

389

Double Bottom Line Project Report:Assessing Social Impact In Double Bottom Line Ventures  

E-Print Network (OSTI)

of Key Characteristics Glossary Method Summaries Theories ofin double bottom line ventures methods catalog glossary ofterms glossary of terms This glossary defines the variables

Rosenzweig, William

2004-01-01T23:59:59.000Z

390

Search for b-->u transitions in B- --> DK- and B- --> D*K- Decays  

SciTech Connect

We report results from an updated study of the suppressed decays B{sup -} --> DK{sup -} and B{sup -} --> D*K{sup -} followed by D --> K{sup +}{pi}{sup -}, where D{sup (*)} indicates a D{sup (*)0} or a {anti D}{sup (*)0} meson, and D{sup *} --> D{tau}{sup 0} or D{sup *} --> D{gamma}. These decays are sensitive to the CKM unitarity triangle angle {gamma} due to interference between the b --> c transition B{sup -} --> D{sup (*)0}K{sup -} followed by the double Cabibbo-suppressed decay D{sup 0} --> K{sup +}{pi}{sup -}, and the b --> u transition B{sup -} --> {anti D}{sup (*)0}K{sup -} followed by the Cabibbo-favored decay {anti D}{sup 0} --> K{sup +}{pi}{sup -}. We also report an analysis of the decay B{sup -} --> D{sup (*)}{pi}{sup -} with the D decaying into the doubly Cabibbo-suppressed mode D --> K{sup +}{pi}{sup -}. Our results are based on 467 million {Upsilon}(4S) --> B{anti B} decays collected with the BABAR detector at SLAC. We measure the ratios R{sup (*)} of the suppressed ([K{sup +}{pi}{sup -}]{sub D}K{sup -}/{pi}{sup -}) to favored ([K{sup -}{pi}{sup +}]{sub D}K{sup -}/{pi}{sup -}) branching fractions as well as the CP asymmetries A{sup (*)} of those modes. We see indications of signals for the B{sup -} --> DK{sup -} and B{sup -} --> D{sup *}{sub D{pi}{sup 0}}K{sup -} suppressed modes, with statistical significances of 2.1 and 2.2{sigma}, respectively, and we measure: R{sub DK} = (1.1 {+-} 0.6 {+-} 0.2) x 10{sup -2}, A{sub DK} = -0.86 {+-} 0.47 {sup +0.12}{sub -0.16}, R{sup *}{sub (D{pi}{sup 0})K} = (1.8 {+-} 0.9 {+-} 0.4) x 10{sup -2}, A{sup *}{sub (D{pi}{sup 0})K} = +0.77 {+-} 0.35 {+-} 0.12, R{sup *}{sub (D{gamma})K} = (1.3 {+-} 1.4 {+-} 0.8) x 10{sup -2}, A{sup *}{sub (D{gamma})K} = +0.36 {+-} 0.94 {sup +0.25}{sub -0.41}, where the first uncertainty is statistical and the second is systematic. we use a frequentist approach to obtain the magnitude of the ratio r{sub B} {equivalent_to} {vert_bar}A(B{sup -} --> {anti D}{sup 0}K{sup -})/A(B{sup -} --> D{sup 0}K{sup -}){vert_bar} = (9.5{sup +5.1}{sub -4.1})%, with r{sub B} < 16.7% at 90% confidence level. In the case of B{sup -} --> D{sup *}K{sup -} we find r{sup *}{sub B} {equivalent_to} {vert_bar}A(B{sup -} --> {anti D}{sup *0}K{sup -})/A(B{sup -} --> D{sup *0}K{sup -}){vert_bar} = (9.6{sup +3.5}{sub 5.1})%, with r{sup *}{sub B} < 15.0% at 90% confidence level.

del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Frascati /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Mississippi U. /Montreal U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Paris U., VI-VII /INFN, Perugia /INFN, Pisa /Princeton U. /Frascati /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-11T23:59:59.000Z

391

Search for di-muon decays of a low-mass Higgs boson in radiative decays of the ?(1S)  

E-Print Network (OSTI)

We search for di-muon decays of a low-mass Higgs boson (A[superscript 0]) produced in radiative ?(1S) decays. The ?(1S) sample is selected by tagging the pion pair in the ?(2S,3S)??[superscript +]?[superscript -]?(1S) ...

Cowan, Ray Franklin

392

Nonaqueous actinide hydride dissolution and production of actinide $beta$- diketonates  

DOE Patents (OSTI)

Actinide beta-diketonate complex molecular compounds are produced by reacting a beta-diketone compound with a hydride of the actinide material in a mixture of carbon tetrachloride and methanol. (auth)

Crisler, L.R.

1975-11-11T23:59:59.000Z

393

Direction of Hurricane Beta Drift in Horizontally Sheared Flows  

Science Conference Proceedings (OSTI)

The impacts of linear environmental shears on beta drift direction are assessed through numerical experiments with a single-layer, primitive equation model. It is found that cyclonic (anticyclonic) shears turn the beta drift more westward (...

Bin Wang; Xiaofan Li; Liguang Wu

1997-06-01T23:59:59.000Z

394

Statistical Properties of a Convoluted Beta-Weibull Distribution.  

E-Print Network (OSTI)

??A new class of distributions recently developed involves the logit of the beta distribution. Among this class of distributions are the beta-normal (Eugene et.al. (2002));… (more)

Sun, Jianan

2011-01-01T23:59:59.000Z

395

Uncertainty evaluation of delayed neutron decay parameters  

E-Print Network (OSTI)

In a nuclear reactor, delayed neutrons play a critical role in sustaining a controllable chain reaction. Delayed neutron’s relative yields and decay constants are very important for modeling reactivity control and have been studied for decades. Researchers have tried different experimental and numerical methods to assess these delayed neutron parameters. The reported parameter values vary widely, much more than the small statistical errors reported with these parameters. Interestingly, the reported parameters fit their individual measurement data well in spite of these differences. This dissertation focuses on evaluation of the errors and methods of delayed neutron relative yields and decay constants for thermal fission of U-235. Various numerical methods used to extract the delayed neutron parameter from the measured data, including Matrix Inverse, Levenberg-Marquardt, and Quasi-Newton methods, were studied extensively using simulated delayed neutron data. This simulated data was Poisson distributed around Keepin’s theoretical data. The extraction methods produced totally different results for the same data set, and some of the above numerical methods could not even find solutions for some data sets. Further investigation found that ill-conditioned matrices in the objective function were the reason for the inconsistent results. To find a reasonable solution with small variation, a regularization parameter was introduced using a numerical method called Ridge Regression. The results from the Ridge Regression method, in terms of goodness of fit to the data, were good and often better than the other methods. Due to the introduction of a regularization number in the algorithm, the fitted result contains a small additional bias, but this method can guarantee convergence no matter how large the coefficient matrix condition number. Both saturation and pulse modes were simulated to focus on different groups. Some of the factors that affect the solution stability were investigated including initial count rate, sample flight time, initial guess values. Finally, because comparing reported delayed neutron parameters among different experiments is useless to determine if their data actually differs, methods are proposed that can be used to compare the delayed neutron data sets.

Wang, Jinkai

2008-12-01T23:59:59.000Z

396

Evidence for the suppressed decay B^- -> DK^-, D -> K^+?^-?^0  

E-Print Network (OSTI)

We report a study of the suppressed decay B^- -> DK^-, D -> K^+\\pi^-\\pi^0, where D denotes either a D^0 or a \\bar{D}^0 meson. The decay is sensitive to the CP-violating parameter \\phi_3. Using a data sample of 772 x 10^6 B\\bar{B} pairs collected at the \\Upsilon(4S) resonance with the Belle detector, we measure the ratio of branching fractions of the above suppressed decay to the favored decay B^- -> DK^-, D -> K^-\\pi^+\\pi^0. Our result is R_{DK} = [1.98 +/- 0.62(stat.) +/- 0.24(syst.)] x 10^{-2}, which indicates the first evidence of the signal for this suppressed decay with a significance of 3.2 standard deviations. We measure the direct CP asymmetry between the suppressed B^- and B^+ decays to be A_{DK} = 0.41 +/- 0.30 (stat.) +/- 0.05 (syst.). We also report measurements for the analogous quantities R_{D\\pi} and A_{D\\pi} for the decay B^- -> D\\pi^-, D -> K^+\\pi^-\\pi^0.

Belle Collaboration; M. Nayak; J. Libby; K. Trabelsi; I. Adachi; H. Aihara; D. M. Asner; T. Aushev; A. M. Bakich; A. Bala; P. Behera; K. Belous; V. Bhardwaj; G. Bonvicini; A. Bozek; M. Bra?ko; T. E. Browder; D. ?ervenkov; M. -C. Chang; P. Chang; V. Chekelian; A. Chen; B. G. Cheon; R. Chistov; I. -S. Cho; K. Cho; V. Chobanova; Y. Choi; D. Cinabro; J. Dalseno; M. Danilov; Z. Doležal; Z. Drásal; D. Dutta; S. Eidelman; S. Esen; H. Farhat; J. E. Fast; T. Ferber; V. Gaur; N. Gabyshev; S. Ganguly; R. Gillard; Y. M. Goh; B. Golob; J. Haba; H. Hayashii; Y. Horii; Y. Hoshi; W. -S. Hou; H. J. Hyun; T. Iijima; A. Ishikawa; T. Iwashita; I. Jaegle; T. Julius; D. H. Kah; E. Kato; D. Y. Kim; H. J. Kim; J. B. Kim; M. J. Kim; Y. J. Kim; K. Kinoshita; J. Klucar; B. R. Ko; P. Kodyš; S. Korpar; P. Krishnan; P. Križan; P. Krokovny; T. Kuhr; T. Kumita; A. Kuzmin; Y. -J. Kwon; S. -H. Lee; J. Li; Y. Li; L. Li Gioi; Y. Liu; D. Liventsev; P. Lukin; H. Miyake; R. Mizuk; G. B. Mohanty; A. Moll; T. Mori; N. Muramatsu; R. Mussa; Y. Nagasaka; M. Nakao; E. Nedelkovska; K. Negishi; C. Ng; N. K. Nisar; O. Nitoh; S. Ogawa; S. Okuno; Y. Onuki; P. Pakhlov; G. Pakhlova; C. W. Park; H. Park; T. K. Pedlar; M. Petri?; L. E. Piilonen; M. Ritter; M. Röhrken; A. Rostomyan; H. Sahoo; T. Saito; Y. Sakai; S. Sandilya; L. Santelj; T. Sanuki; V. Savinov; O. Schneider; G. Schnell; C. Schwanda; A. J. Schwartz; K. Senyo; O. Seon; M. E. Sevior; M. Shapkin; C. P. Shen; T. -A. Shibata; J. -G. Shiu; B. Shwartz; A. Sibidanov; F. Simon; Y. -S. Sohn; A. Sokolov; E. Solovieva; M. Stari?; M. Steder; Z. Suzuki; U. Tamponi; G. Tatishvili; Y. Teramoto; M. Uchida; T. Uglov; Y. Unno; S. Uno; P. Urquijo; S. E. Vahsen; C. Van Hulse; P. Vanhoefer; G. Varner; K. E. Varvell; M. N. Wagner; C. H. Wang; M. -Z. Wang; Y. Watanabe; K. M. Williams; E. Won; Y. Yamashita; S. Yashchenko; Y. Yusa; V. Zhilich; V. Zhulanov; A. Zupanc

2013-10-07T23:59:59.000Z

397

Method for conversion of .beta.-hydroxy carbonyl compounds  

DOE Patents (OSTI)

A process is disclosed for conversion of salts of .beta.-hydroxy carbonyl compounds forming useful conversion products including, e.g., .alpha.,.beta.-unsaturated carbonyl compounds and/or salts of .alpha.,.beta.-unsaturated carbonyl compounds. Conversion products find use, e.g., as feedstock and/or end-use chemicals.

Lilga, Michael A. (Richland, WA); White, James F. (Richland, WA); Holladay, Johnathan E. (Kennewick, WA); Zacher, Alan H. (Kennewick, WA); Muzatko, Danielle S. (Kennewick, WA); Orth, Rick J. (Kennewick, WA)

2010-03-30T23:59:59.000Z

398

Branching Fraction Measurements of the Color-Suppressed Decays B0bar to D(*)0 pi0, D(*)0 eta, D(*)0 omega, and D(*)0 eta_prime and Measurement of the Polarization in the Decay B0bar to D*0 omega  

SciTech Connect

We report updated branching fraction measurements of the color-suppressed decays {bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}, D*{sup 0}{pi}{sup 0}, D{sup 0}{eta}, D*{sup 0}{eta}, D{sup 0}{omega}, D*{sup 0}{omega}, D{sup 0}{eta}', and D*{sup 0}{eta}'. We measure the branching fractions (x10{sup -4}): {Beta}({bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}) = 2.69 {+-} 0.09 {+-} 0.13, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{pi}{sup 0}) = 3.05 {+-} 0.14 {+-} 0.28, {Beta}({bar B}{sup 0} {yields} D{sup 0}{eta}) = 2.53 {+-} 0.09 {+-} 0.11, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{eta}) = 2.69 {+-} 0.14 {+-} 0.23, {Beta}({bar B}{sup 0} {yields} D{sup 0}{omega}) = 2.57 {+-} 0.11 {+-} 0.14, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{omega}) = 4.55 {+-} 0.24 {+-} 0.39, {Beta}({bar B}{sup 0} {yields} D{sup 0}{eta}') = 1.48 {+-} 0.13 {+-} 0.07, and {Beta}({bar B}{sup 0} {yields} D*{sup 0}{eta}') = 1.49 {+-} 0.22 {+-} 0.15. We also present the first measurement of the longitudinal polarization fraction of the decay channel D*{sup 0}{omega}, f{sub L} = (66.5 {+-} 4.7 {+-} 1.5)%. In the above, the first uncertainty is statistical and the second is systematic. The results are based on a sample of (454 {+-} 5) x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance, with the BABAR detector at the PEP-II storage rings at SLAC. The measurements are the most precise determinations of these quantities from a single experiment. They are compared to theoretical predictions obtained by factorization, Soft Collinear Effective Theory (SCET) and perturbative QCD (pQCD). We find that the presence of final state interactions is favored and the measurements are in better agreement with SCET than with pQCD.

Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U. /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2012-02-14T23:59:59.000Z

399

Extracellular oxidative metabolism of wood decay fungi  

DOE Green Energy (OSTI)

Substantial progress has been made toward understanding the fundamental physiology and genetics of wood decay fungi, microbes that are capable of degrading all major components of plant cell walls. Efficient utilization of lignocellulosic biomass has been hampered in part by limitations in our understanding of enzymatic mechanisms of plant cell wall degradation. This is particularly true of woody substrates where accessibility and high lignin content substantially complicate enzymatic 'deconstruction'. The interdisciplinary research has illuminated enzymatic mechanisms essential for the conversion of lignocellulosics to simple carbohydrates and other small molecular weight products. Progress was in large part dependent on substantial collaborations with the Department of Energy's Joint Genome Institute (JGI) in Walnut Creek and Los Alamos, as well as the Catholic University, Santiago, Chile, the Royal Institute of Technology, Stockholm, the University of Minnesota, St. Paul, and colleagues at the University of Wisconsin and the Forest Products Laboratory. Early accomplishments focused on the development of experimental tools (2, 7, 22, 24-26, 32) and characterization of individual genes and enzymes (1, 3-5, 8, 9, 11, 14, 15, 17, 18, 23, 27, 33). In 2004, the genome of the most intensively studied lignin-degrading fungus, Phanerochaete chrysosporium, was published (21). This milestone lead to additional progress on this important model system (6, 10, 12, 13, 16, 28-31) and was further complemented by genome analysis of other important cellulose-degrading fungi (19, 20). These accomplishments have been highly cited and have paved the way for whole new research areas.

Daniel Cullen

2010-04-21T23:59:59.000Z

400

Searches for New Physics in Top Decays at D0  

Science Conference Proceedings (OSTI)

The Tevatron proton-antiproton collider at Fermilab with its centre of mass energy of 1.96 TeV allows for pair production of top quarks and the study of top quark decay properties. This report reflects the current status of measurements of the W boson helicity in top quark decays and the ratio of top quark branching fractions as well as searches for neutral current top quark decays and pair production of fourth generation t' quarks, performed by the D0 Collaboration utilising datasets of up to 5.4 fb{sup -1}.

Pleier, Marc-Andre; /Brookhaven

2011-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Update analysis of two-body charmed $B$ meson decays  

E-Print Network (OSTI)

The charmed B decays, $B\\to DP, ~D^*P$ and $DV$, are re-analyzed using the latest experimental data, where $P$ and $V$ denote the pseudoscalar meson and vector meson, respectively. We perform global fits under the assumption of flavor SU(3) symmetry. The size of the decay amplitudes and the strong phases between the topologically distinct amplitudes are studied. Predictions of the related $B_s$ decay rates are made based upon the fitted results. We also note a serious SU(3) symmetry breaking or inconsistency in the $DV$ sector.

Chiang, C W; Chiang, Cheng-Wei; Senaha, Eibun

2007-01-01T23:59:59.000Z

402

Crystallographic variant selection in {alpha}-{beta} brass  

Science Conference Proceedings (OSTI)

The transformation texture of {alpha}/{beta} brass with a diffusional Widmanstaetten {alpha} growth morphology has been investigated. Electron micrographs and electron backscattered diffraction was used to determine that the orientation relationship between the {beta} phase and the {alpha} associated with nucleation at {beta} grain boundaries was 44.3 deg . Crystallographic variant selection was observed across those prior {beta}/{beta} grain boundaries, but this has little effect on the transformation texture due to the crystal symmetry. The effect of the crystallographic variant selection on texture is further weakened by nucleation of diffusional transformed {alpha} in the grain interior.

Stanford, N. [Manchester Materials Science Centre, University of Manchester, Grosvenor Street, Manchester M1 7HS (United Kingdom); Bate, P.S. [Manchester Materials Science Centre, University of Manchester, Grosvenor Street, Manchester M1 7HS (United Kingdom)]. E-mail: pete.bate@man.ac.uk

2005-02-01T23:59:59.000Z

403

Beta optimization in the context of reactor relevant tokamaks  

SciTech Connect

In a reactor relevant tokamak the appropriate definition of {beta}, the ratio of the particle and magnetic field pressures, is {beta}* {equivalent to} (2 < p{sup 2} >{sup {1/2}} /B{sup 2}), which exceeds the conventional definition by a factor dependent on the pressure peaking factor, PPF. A simple scaling is obtained which relates the two definitions, {beta}*/{beta}{approx equal}0.9 {plus} 0.15 PPF. Stability properties are determined in terms of {beta}* in a circular and dee-shaped tokamak. 4 refs., 6 figs.

Manickam, J.

1990-08-01T23:59:59.000Z

404

Numerical models for high beta magnetohydrodynamic flow  

Science Conference Proceedings (OSTI)

The fundamentals of numerical magnetohydrodynamics for highly conducting, high-beta plasmas are outlined. The discussions emphasize the physical properties of the flow, and how elementary concepts in numerical analysis can be applied to the construction of finite difference approximations that capture these features. The linear and nonlinear stability of explicit and implicit differencing in time is examined, the origin and effect of numerical diffusion in the calculation of convective transport is described, and a technique for maintaining solenoidality in the magnetic field is developed. Many of the points are illustrated by numerical examples. The techniques described are applicable to the time-dependent, high-beta flows normally encountered in magnetically confined plasmas, plasma switches, and space and astrophysical plasmas. 40 refs.

Brackbill, J.U.

1987-01-01T23:59:59.000Z

405

A Toy Model Study of Decay Trapping | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

A Toy Model Study of Decay Trapping, reported by Brett Parker A Toy Model Study of Decay Trapping, reported by Brett Parker Introduction A group from the BNL Superconducting Magnet Division is looking at various options for dipole magnets which would be suitable for use in a muon storage ring that is used as a neutrino factory. Since the useful neutrino beams from a neutrino factory come from straight sections it is desirable to minimize the rings arc circumference, in relation to straight section length, in order to ensure that the fraction of muons which decay in the straight section is as large as possible. Therefore superconducting magnets, with higher B-fields and smaller bend radii, are reasonable to consider for this application. Unfortunately the decay electrons generated along with the neutrinos carry on average about a third of the original

406

Large-Eddy Simulation of Decaying Stably Stratified Turbulence  

Science Conference Proceedings (OSTI)

A large-eddy simulation (LES) model is developed and employed to study the interactions among turbulent and internal gravity wave motions in a uniformly stratified fluid at oceanic space and time scales. The decay of a random initial energy ...

David A. Siegel; J. Andrzej Domaradzki

1994-11-01T23:59:59.000Z

407

Evidence of the Higgs Boson Decaying into Two Photons.  

E-Print Network (OSTI)

??A search for the standard model Higgs boson decaying to two photons will be presented. The analysis will cover 5.1 fb-1 and 19.6 fb-1 of… (more)

Berry, Douglas R

2013-01-01T23:59:59.000Z

408

Decay of the Navier-Stokes-Poisson equations  

E-Print Network (OSTI)

We establish the time decay rates of the solution to the Cauchy problem for the compressible Navier-Stokes-Poisson system via a refined pure energy method. In particular, the optimal decay rates of the higher-order spatial derivatives of the solution are obtained. The $\\Dot{H}^{-s}$($0\\le srates. As a corollary, we also obtain the usual $L^p$--$L^2$($1rates. Compared to the compressible Navier-Stokes system and the compressible irrotational Euler-Poisson system, our results imply that both the dispersion effect of the electric field and the viscous dissipation contribute to enhance the decay rate of the density. Our proof is based on a family of scaled energy estimates with minimum derivative counts and interpolations among them without linear decay analysis.

Wang, Yanjin

2011-01-01T23:59:59.000Z

409

Dynamics of Excimer Formation and Decay in Supercritical Krypton  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynamics of Excimer Formation and Decay in Supercritical Krypton R. A. Holroyd, A. R. Cook and J. M. Preses J. Chem. Phys. 131, 224509 (2009). Find paper at Scitation Abstract:...

410

Lepton flavor violation decays with the fourth generation neutrino  

E-Print Network (OSTI)

We investigate the lepton flavor violation decays, $\\tau \\to \\mu\\gamma$, $\\tau \\to e\\gamma$ and $\\mu \\to e\\gamma$, in the framwork of a squential fourth generation model with a heavy fourth neutrino, $\

Huo, W J; Huo, Wu-Jun; Feng, Tai-Fu

2002-01-01T23:59:59.000Z

411

Modal Decay in the Australia–Antarctic Basin  

Science Conference Proceedings (OSTI)

The barotropic intraseasonal variability in the Australia–Antarctic Basin (AAB) is studied in terms of the excitation and decay of topographically trapped barotropic modes. The main objective is to reconcile two widely differing estimates of the ...

Wilbert Weijer; Sarah T. Gille; Frédéric Vivier

2009-11-01T23:59:59.000Z

412

DECAY HEAT CONDITIONS OF CURRENT AND NEXT GENERATION REACTORS  

E-Print Network (OSTI)

Decay heat is an important parameter in reactor design. Fission products generate heat in the reactor core even when the reactor has shut down. This heat has potential to melt the core if heat removal is not sufficient, and it is what caused the accident in Japan last year. Thus, decay heat must be considered in reactor design for safety. The research focused on decay heat conditions of current and next generation reactors. US-APWR, ABWR, VHTR, and ABR were modeled and simulated using the program SCALE. When the reactors were simulated to operate for two years and cool down for one year, the ABR produced the most decay heat power during operation and cooling time, and the US-APWR, VHTR, and ABWR followed respectfully. Therefore, the ABR requires more coolant and cooling time than other reactors, and the ABWR requires the least.

Choe, JongSoo 1985-

2012-05-01T23:59:59.000Z

413

The “Footprint” under a Decaying Tropical Mesoscale Convective System  

Science Conference Proceedings (OSTI)

On 10 February 1993, during the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment, the two NOAA WP-3Ds and the NCAR Electra flew under the anvil region of a decaying mesoscale convective system (MCS). Satellite and ...

Mark F. Geldmeier; Gary M. Barnes

1997-11-01T23:59:59.000Z

414

MEASUREMENT OF yyy FINAL STATES IN y DECAY  

E-Print Network (OSTI)

Fig. 2. The high mass projection of these data clearly showsdominate the low mass projection. There is no evidence inline in the high mass projection of Fig. 2. decays is The

Himel, T.M.

2013-01-01T23:59:59.000Z

415

Renewal convergence rates and correlation decay for homogeneous pinning models  

E-Print Network (OSTI)

A class of discrete renewal processes with super-exponentially decaying inter-arrival distributions coincides with the infinite volume limit of general homogeneous pinning models in their localized phase. Pinning models are statistical mechanics systems to which a lot of attention has been devoted both for their relevance for applications and because they are solvable models exhibiting a non-trivial phase transition. The spatial decay of correlations in these systems is directly mapped to the speed of convergence to equilibrium for the associated renewal processes. We show that close to criticality, under general assumptions, the correlation decay rate, or the renewal convergence rate, coincides with the inter-arrival decay rate. We also show that, in general, this is false away from criticality. Under a stronger assumption on the inter-arrival distribution we establish a local limit theorem, capturing thus the sharp asymptotic behavior of correlations.

Giacomin, Giambattista

2007-01-01T23:59:59.000Z

416

Renewal convergence rates and correlation decay for homogeneous pinning models  

E-Print Network (OSTI)

A class of discrete renewal processes with super-exponentially decaying inter-arrival distributions coincides with the infinite volume limit of general homogeneous pinning models in their localized phase. Pinning models are statistical mechanics systems to which a lot of attention has been devoted both for their relevance for applications and because they are solvable models exhibiting a non-trivial phase transition. The spatial decay of correlations in these systems is directly mapped to the speed of convergence to equilibrium for the associated renewal processes. We show that close to criticality, under general assumptions, the correlation decay rate, or the renewal convergence rate, coincides with the inter-arrival decay rate. We also show that, in general, this is false away from criticality. Under a stronger assumption on the inter-arrival distribution we establish a local limit theorem, capturing thus the sharp asymptotic behavior of correlations.

Giambattista Giacomin

2007-06-03T23:59:59.000Z

417

THEORETICAL ASPECTS OF NONLEPTONIC HYPERON DECAYS  

SciTech Connect

Recent experimental results on nonleptonic hyperon decays are studied on the basis of a doublet approximation for strong and weak interactions, with the implied suggestion that this higher symmetry may be more easlly discernable in such reactions in which K-panticles do not occur explicitly. The doublet approximation is characterized by a doublet spin I which is equal to 1/2, 1, 0 for baryons, pi , K, respectively, and by a K spin. It is not necessary to assume that the strong K interactions are weak compared to the strong pi interactions. For the mentioned reactions it is necessary to assume that the strong interactions which do not conserve I play a minor role compared to those which conserve I. The following refinement of the nonleptonic DELTA T = 1/2 rule is proposed. (T = isotopic spin.) The weak nonleptonic interactions consist of two parts H/sup (0)/, H/sup (1)/ with DELTA I = 0, 1, respectively. In the doublet approximation H/sup (o)/ and H/sup (1)/ separately conserve parity in the presence of all strong pi and K interactions. H/sup (o)/ and H/sup (1)/ together do not conserve parity, however. In addition to DELTA I = 1, H/sup )1)/ should in general satisfy a further constraint, but there are classes of graphs for which DELTA I = 1 is sufficient. Current x current structures for H/sup (o)/ and H/sup (1)/ are examined. Resul ts of an earlier paper can be viewed as a special case of the DELTA I = 0, 1 rule. The same is true for results obtained by Feldman, Matthews, and Salam and by Woifenstein. The considerations of these authors can be extended to wider classes of graphs. Odd relative helicity and the relation between rates for LAMBDA -- p + pi -, SIGMA + -- p + pi /sup o/ are consequences of the DELTA I = 0, 1 rule only. So is the prediction that XI decay is strongly P nonconserving. The parity properties of H/sup (o)/ H/sup (1)/ are sufficient conditions. It is a delicate question whether they are necessary. For a subset of graphs they are not necessary, but this set seems arbitrary. If it is assumed that the parity conditions are necessary, the schizon scheme is ruled out. It is noted that the nonleptonic weak interactions may be generated by the strong interactions in terms of the following prescription. H/sup (1)/ is generated by assuming that the pi (K) fields have small K( pi ) components. An H/sup (o)/ is generated by assuming that the doublets N/sup 1/(N/sup 2/) have small N/sub 2/(N/sub 1/) components; likewise for N/sub 3/ and N/sub 4/. Further, it is observed thai one can construct a non- electromagnetic DELTA T =3/2 interaction which is small in the sense that it only contributes to K/sub pi //sub 2+/ to the extent t hat the doublet approximation is not valid. (auth)

Pais, A.

1961-04-01T23:59:59.000Z

418

Searching for the fourth family quarks through anomalous decays  

Science Conference Proceedings (OSTI)

The flavor democracy hypothesis predicts the existence of the fourth standard model family. Because of the high masses of the fourth family quarks, their anomalous decays could be dominant if certain criteria are met. This will drastically change the search strategy at hadron colliders. We show that the fourth standard model family down quarks with masses up to 400-450 GeV can be observed (or excluded) via anomalous decays by Tevatron.

Sahin, M.; Sultansoy, S.; Turkoz, S. [TOBB University of Economics and Technology, Physics Division, Ankara (Turkey); TOBB University of Economics and Technology, Physics Division, Ankara, Turkey and Institute of Physics, National Academy of Sciences, Baku (Azerbaijan); Ankara University, Department of Physics, Ankara (Turkey)

2010-09-01T23:59:59.000Z

419

Constraining gamma from K* pi and rho K Decays  

E-Print Network (OSTI)

We show that information on the weak phase gamma can be extracted from the K* pi and rho K decays. Less hadronic uncertainty is involved when the observables of four of these modes are combined together. We further point out two approximate relations in these decay modes can help determine whether there are new physics contributions in Delta I = 1 transitions, as hinted in the K pi modes.

Cheng-Wei Chiang

2005-02-20T23:59:59.000Z

420

Constraining gamma from K* pi and rho K Decays  

E-Print Network (OSTI)

We show that information on the weak phase gamma can be extracted from the K* pi and rho K decays. Less hadronic uncertainty is involved when the observables of four of these modes are combined together. We further point out two approximate relations in these decay modes can help us determining whether there are new physics contributions in Delta I = 1 transitions, as hinted in the K pi modes.

Chiang, C W

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "double beta decay" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

The strong coupling from tau decays without prejudice  

E-Print Network (OSTI)

We review our recent determination of the strong coupling \\alpha_s from the OPAL data for non-strange hadronic tau decays. We find that \\alpha_s(m^2_\\tau) =0.325+-0.018 using fixed-order perturbation theory, and \\alpha_s(m^2_\\tau)=0.347+-0.025 using contour-improved perturbation theory. At present, these values supersede any earlier determinations of the strong coupling from hadronic tau decays, including those from ALEPH data.

Boito, Diogo; Jamin, Matthias; Mahdavi, Andisheh; Maltman, Kim; Osborne, James; Peris, Santiago

2012-01-01T23:59:59.000Z

422

Effects of Vacuum Fluctuation Suppression on Atomic Decay Rates  

E-Print Network (OSTI)

The use of atomic decay rates as a probe of sub-vacuum phenomena will be studied. Because electromagnetic vacuum fluctuations are essential for radiative decay of excited atomic states, decay rates can serve as a measure of the suppression of vacuum fluctuation in non-classical states, such as squeezed vacuum states. In such states the renormalized expectation value of the square of the electric field or the energy density can be periodically negative, representing suppression of vacuum fluctuations. We explore the extent to which atomic decays can be used to measure the mean squared electric field or energy density. We consider a scheme in which atoms in an excited state transit a closed cavity whose lowest mode contains photons in a non-classical state. The change in the decay probability of the atom in the cavity due to the non-classical state can, under certain circumstances, serve as a measure of the mean squared electric field or energy density in the cavity. We derive a quantum inequality bound on the decrease in this probability. We also show that the decrease in decay rate can sometimes be a measure of negative energy density or negative squared electric field. We make some estimates of the magnitude of this effect, which indicate that an experimental test might be possible.

L. H. Ford; Thomas A. Roman

2009-07-09T23:59:59.000Z

423

Observation of Tau Decays with Two Neutral Kaons  

E-Print Network (OSTI)

We report on the observation of the decay \\Gamma ! K 0 K 0 \\Gamma in 3.11 fb \\Gamma1 of data taken with the CLEO II detector at the Cornell Electron Storage Ring. Both K 0 mesons are detected through their decays via K S ! + \\Gamma . Preliminary results on the branching fraction and on the resonant substructure are presented. In particular, we find B( \\Gamma ! K 0 K 0 \\Gamma ) = 0:083 \\Sigma 0:017 \\Sigma 0:017 %. We also comment on the sensitivity of the KK invariant mass spectrum to a non-zero tau-neutrino mass. Permanent address: University of Hawaii at Manoa y Permanent address: INP, Novosibirsk, Russia 2 I. INTRODUCTION Tau lepton decays of the type \\Gamma ! [KK] \\Gamma have been known to exist [1] for nearly a decade. However, due to the small decay width and difficulties associated with identifying kaons, little information is presently available for these decays. In this paper, we report on the observation of KK decays where both...

Balest Cho Ford; Ichep Ref; Gsl Cleo Conf; K. Cho; K. Lingel; M. Lohner; P. Rankin

1994-01-01T23:59:59.000Z

424

Gamma-Ray Lines from Radiative Dark Matter Decay  

E-Print Network (OSTI)

The decay of dark matter particles which are coupled predominantly to charged leptons has been proposed as a possible origin of excess high-energy positrons and electrons observed by cosmic-ray telescopes PAMELA and Fermi LAT. Even though the dark matter itself is electrically neutral, the tree-level decay of dark matter into charged lepton pairs will generically induce radiative two-body decays of dark matter at the quantum level. Using an effective theory of leptophilic dark matter decay, we calculate the rates of radiative two-body decays for scalar and fermionic dark matter particles. Due to the absence of astrophysical sources of monochromatic gamma rays, the observation of a line in the diffuse gamma-ray spectrum would constitute a strong indication of a particle physics origin of these photons. We estimate the intensity of the gamma-ray line that may be present in the energy range of a few TeV if the dark matter decay interpretation of the leptonic cosmic-ray anomalies is correct and comment on observational prospects of present and future Imaging Cherenkov Telescopes, in particular the CTA.

Mathias Garny; Alejandro Ibarra; David Tran; Christoph Weniger

2010-11-16T23:59:59.000Z

425

B Decay and CP Violation: CKM Angles and Sides at the BABAR and BELLE B-Factories  

Science Conference Proceedings (OSTI)

A remarkable success has been achieved by the B-Factories, going beyond expectation in some field, like the measurement of {gamma}. BABAR has now finished its data taking, leaving BELLE alone in the 'race', but still many analyses are going on. The CKM UT is constrained by both measurements of CP-conserving and CP-violating quantities, leading to a picture of the CKM sector consistent with the SM. Measurements of semi-leptonic decays benefit from improving experimental techniques and more precise theoretical computations. The angle {beta} is a precision measurement, reaching accuracy of SM calculation. The angle {alpha} will ultimatly be limited by penguin pollution. The measurement of {gamma} is reaching the 13{sup o} precision.

Verderi, Marc; /Ecole Polytechnique

2011-11-28T23:59:59.000Z

426

A Microscopic Double-Slit Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

A Microscopic Double-Slit A Microscopic Double-Slit Experiment A Microscopic Double-Slit Experiment Print Wednesday, 29 February 2012 00:00 Two centuries ago, Thomas Young performed the classic demonstration of the wave nature of light. He placed a screen with two tiny slits in front of a single light source, effectively converting it into a two-centered source. On a second screen far away, he saw a pattern of light and dark diffraction fringes, a well-known hallmark of wave interference. Along with later studies using particles instead of light, the experiment played a crucial role in establishing the validity of wave-particle duality, a puzzling concept that has ultimately become central to the interpretation of complementarity in quantum mechnanics. In a new twist on this classic experiment, the double slit (with light waves) has been replaced by a diatomic molecule (with electron waves). At ALS Beamline 10.0.1, researchers have shown that diatomic molecules can serve as two-center emitters of electron waves and that traces of electron-wave interference can be directly observed in precise measurements of vibrationally resolved photoionization spectra.

427

The Dynamics of Double Monsoon Onsets  

Science Conference Proceedings (OSTI)

Double monsoon onset develops when the strong convection in the Bay of Bengal is accompanied by the monsoonlike circulation and appears in the Indian Ocean in early May, which is about 3 weeks earlier than the climatological date of the onset (1 ...

Maria K. Flatau; Piotr J. Flatau; Daniel Rudnick

2001-11-01T23:59:59.000Z

428

Double?Quantum Light Scattering by Molecules  

Science Conference Proceedings (OSTI)

Double?quantum light scattering by a system of molecules is discussed in this paper. Expressions have been obtained for the scattered light intensity considering both the coherent and incoherent contributions. In that coherent contributions are also considered in this treatment

R. Bersohn; Yoh?Han Pao; H. L. Frisch

1966-01-01T23:59:59.000Z

429

Passive air cooling of liquid metal-cooled reactor with double vessel leak accommodation capability  

DOE Patents (OSTI)

A passive and inherent shutdown heat removal method with a backup air flow path which allows decay heat removal following a postulated double vessel leak event in a liquid metal-cooled nuclear reactor is disclosed. The improved reactor design incorporates the following features: (1) isolation capability of the reactor cavity environment in the event that simultaneous leaks develop in both the reactor and containment vessels; (2) a reactor silo liner tank which insulates the concrete silo from the leaked sodium, thereby preserving the silo`s structural integrity; and (3) a second, independent air cooling flow path via tubes submerged in the leaked sodium which will maintain shutdown heat removal after the normal flow path has been isolated. 5 figures.

Hunsbedt, A.; Boardman, C.E.

1995-04-11T23:59:59.000Z

430

Passive air cooling of liquid metal-cooled reactor with double vessel leak accommodation capability  

SciTech Connect

A passive and inherent shutdown heat removal method with a backup air flow path which allows decay heat removal following a postulated double vessel leak event in a liquid metal-cooled nuclear reactor. The improved reactor design incorporates the following features: (1) isolation capability of the reactor cavity environment in the event that simultaneous leaks develop in both the reactor and containment vessels; (2) a reactor silo liner tank which insulates the concrete silo from the leaked sodium, thereby preserving the silo's structural integrity; and (3) a second, independent air cooling flow path via tubes submerged in the leaked sodium which will maintain shutdown heat removal after the normal flow path has been isolated.

Hunsbedt, Anstein (Los Gatos, CA); Boardman, Charles E. (Saratoga, CA)

1995-01-01T23:59:59.000Z

431

PNNL offers 'virtual tour' of Shallow Underground Laboratory...  

National Nuclear Security Administration (NNSA)

for the Comprehensive-Nuclear-Test Ban Treaty to basic science research such as the search for dark matter in the universe or neutrinoless double-beta decay. The virtual tour...

432

Interatomic Coulombic decay following Ne 1s Auger decay in NeAr  

SciTech Connect

Using momentum-resolved electron-ion multicoincidence spectroscopy, we have investigated interatomic Coulombic decay (ICD) in the heteronuclear NeAr dimer following Ne 1s Auger decay. The measured intensity ratio for the three ICD transitions Ne{sup 2+}(2s{sup -1}2p{sup -1} {sup 1}P)Ar to Ne{sup 2+}(2p{sup -2} {sup 1}S)-Ar{sup +}(3p{sup -1}), Ne{sup 2+}(2s{sup -1}2p{sup -1} {sup 1}P)Ar to Ne{sup 2+}(2p{sup -2} {sup 1}D)-Ar{sup +}(3p{sup -1}), and Ne{sup 2+}(2s{sup -1}2p{sup -1} {sup 3}P)Ar to Ne{sup 2+}(2p{sup -2} {sup 3}P)-Ar{sup +}(3p{sup -1}) reasonably agree with predictions. The kinetic energy release distribution for the fragmentation to Ne{sup 2+}(2p{sup -2} {sup 1}D)-Ar{sup +}(3p{sup -1}) after the ICD transition from singlet Ne{sup 2+}(2s{sup -1}2p{sup -1} {sup 1}P)Ar state, which is a mirror image of the kinetic energy distribution of the emitted ICD electrons, suggests that the corresponding ICD rate is roughly two times lower than predicted by ab initio calculations.

Ouchi, T.; Sakai, K.; Fukuzawa, H.; Ueda, K. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Higuchi, I.; Tamenori, Y. [Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198 (Japan); Demekhin, Ph. V.; Chiang, Y.-C.; Stoychev, S. D.; Kuleff, A. I. [Theoretische Chemie, Universitaet Heidelberg, D-69120 Heidelberg (Germany); Mazza, T. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Cimaina and Dipartimento di Fisica, Universita degli Studi di Milano, via Celoria 16, I-20133 Milano (Italy); Schoeffler, M. [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Nagaya, K.; Yao, M. [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan); Saito, N. [National Institute of Advanced Industrial Science and Technology, National Meteorology Institute of Japan, Tsukuba 305-8568 (Japan)

2011-05-15T23:59:59.000Z

433

Next-Generation Liquid-Scintillator-Based Detectors: Quantums Dots and Picosecond Timing  

E-Print Network (OSTI)

Liquid-scintillator-based detectors are a robust technology that scales well to large volumes. For this reason, they are attractive for experiments searching for neutrinoless double-beta decay. A combination of improved photo-detection technology and novel liquid scintillators may allow for the extraction of particle direction in addition to the total energy of the particle. Such an advance would find applications beyond searches for neutrinoless double-beta decay.

Lindley Winslow

2013-07-10T23:59:59.000Z

434

Search for the Flavor Changing Neutral Current Decay t --> Z q at sqrt(s) = 1.96 TeV  

SciTech Connect

This thesis reports the results of a search for the flavor changing neutral current decay of the top quark, t {yields} Zq, in decays of t{bar t} pairs produced in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. This search is performed on a data sample recorded by the Collider Detector at Fermilab (CDF), corresponding to an integrated luminosity of 1.9 fb{sup -1}. This search follows a previous CDF analysis that resulted in an upper limit for the branching fraction {Beta}(t {yields} Zq) of 10.4% at 95% C.L. using a dataset equivalent to 1.1 fb{sup -1} of integrated luminosity. This thesis extends to 1.9 fb{sup -1} of data, and has improved sensitivity to the small signal with the introduction of a template fit technique that includes systematic uncertainties by a linear interpolation between templates. Using a Feldman-Cousins construction, an upper limit at 95% C.L. is set on {Beta}(t {yields} Zq) of 3.7%, with the expected upper limit in absence of a signal is 5.0 {+-} 2.2% for a top mass of 175 GeV/c{sup 2}.

Gimmell, Jennifer Lindsay; /Rochester U.

2009-01-01T23:59:59.000Z

435

Preparation of reactive beta-dicalcium silicate  

DOE Patents (OSTI)

This invention relates to the preparation of fine particles of reactive beta-dicalcium silicate by means of a solid state process which comprises firing a mixture of calcium sulfate, silica and a reducing additive selected from the group consisting of calcium sulfide, carbon, carbon monoxide, methane and hydrogen, at a temperature of about 850.degree.-1000.degree. C. A carrier gas such as nitrogen or carbon dioxide may also be added, if desired. A high concentration of sulfur dioxide is a by-product of this process.

Shen, Ming-Shing (Laramie, WY, NJ); Chen, James M. (Rahway, NJ); Yang, Ralph T. (Amherst, NY)

1982-01-01T23:59:59.000Z

436

Preparation of reactive beta-dicalcium silicate  

DOE Patents (OSTI)

This invention relates to the preparation of fine particles of reactive beta-dicalcium silicate by means of a solid state process which comprises firing a mixture of calcium sulfate, silica, and a reducing additive selected from the group consisting of calcium sulfide, carbon, carbon monoxide, methane, and hydrogen, at a temperature of about 850 to 1000/sup 0/C. A carrier gas such as nitrogen or carbon dioxide may also be added, if desired. A high concentration of sulfur dioxide is a by-product of this process.

Shen, M.S.; Chen, J.M.; Yang, R.T.

1980-02-28T23:59:59.000Z

437

Carports with Solar Panels do Double Duty for Navy | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Carports with Solar Panels do Double Duty for Navy Carports with Solar Panels do Double Duty for Navy May 14, 2010 - 12:22pm Addthis Joshua DeLung What does this project do? In...

438

EA-1136: Double Tracks Test Site, Nye County, Nevada | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

6: Double Tracks Test Site, Nye County, Nevada EA-1136: Double Tracks Test Site, Nye County, Nevada SUMMARY This EA evaluates the environmental impacts of the proposal for the U.S....

439

The Small Quantum Group as a Quantum Double  

E-Print Network (OSTI)

We prove that the quantum double of the quasi-Hopf algebra View the MathML source of We prove that the quantum double of the quasi-Hopf algebra Aq(g)

Etingof, Pavel I.

440

Y-12 Beta-3 Racetracks | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Y-12 Beta-3 Racetracks Y-12 Beta-3 Racetracks Y-12 Beta-3 Racetracks Y-12 Beta-3 Racetracks Built near the northeastern end of the Oak Ridge reservation, the Y-12 facility used the electromagnetic method to separate uranium-235 from the uranium-238 in natural uranium. During the Manhattan Project, Y-12 housed nine Alpha and eight Beta racetracks, which were arrangements of huge electromagnets containing a number of calutrons in the magnets' gaps. The calutrons sent a stream of charged particles through the magnetic field, deflecting the atoms of the lighter isotope more than those of the heavier isotope. This resulted in two streams that could be collected in different sections of the receivers. Containing 96 calutron tanks, each Alpha track was 122 feet long, 77 feet wide, and 15 feet high. Beta tracks were

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441

Fact Sheet: Sodium-Beta Batteries (October 2012)  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Sodium-Beta Batteries Sodium-Beta Batteries Improving the performance and reducing the cost of sodium-beta batteries for large-scale energy storage Sodium-beta batteries (Na-beta batteries or NBBs) use a solid beta-alumina (ß˝-Al 2 O 3 ) electrolyte membrane that selectively allows sodium ion transport between a positive electrode (e.g., a metal halide) and a negative sodium electrode. NBBs typically operate at temperatures near 350˚C. They are increasingly used in renewable storage and utility applications due to their high round-trip efficiency, high energy densities, and energy storage capacities ranging from a few kilowatt-hours to multiple megawatt-hours. In fact, U.S. utilities

442

Double layer capacitance of carbon foam electrodes  

DOE Green Energy (OSTI)

We have evaluated a wide variety of microcellular carbon foams prepared by the controlled pyrolysis and carbonization of several polymers including: polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), resorcinol/formaldehyde (RF), divinylbenzene/methacrylonitrile (DVB), phenolics (furfuryl/alcohol), and cellulose polymers such as Rayon. The porosity may be established by several processes including: Gelation (1-5), phase separation (1-3,5-8), emulsion (1,9,10), aerogel/xerogel formation (1,11,12,13), replication (14) and activation. In this report we present the complex impedance analysis and double layer charging characteristics of electrodes prepared from one of these materials for double layer capacitor applications, namely activated cellulose derived microcellular carbon foam.

Delnick, F.M.; Ingersoll, D. [Sandia National Labs., Albuquerque, NM (United States); Firsich, D. [EG& G Mound Lab., Miamisburg, OH (United States)

1993-11-01T23:59:59.000Z

443

Effects of Vacuum Fluctuation Suppression on Atomic Decay Rates  

E-Print Network (OSTI)

The use of atomic decay rates as a probe of sub-vacuum phenomena will be studied. Because electromagnetic vacuum fluctuations are essential for radiative decay of excited atomic states, decay rates can serve as a measure of the suppression of vacuum fluctuation in non-classical states, such as squeezed vacuum states. In such states the renormalized expectation value of the square of the electric field or the energy density can be periodically negative, representing suppression of vacuum fluctuations. We explore the extent to which atomic decays can be used to measure the mean squared electric field or energy density. We consider a scheme in which atoms in an excited state transit a closed cavity whose lowest mode contains photons in a non-classical state. The change in the decay probability of the atom in the cavity due to the non-classical state can, under certain circumstances, serve as a measure of the mean squared electric field or energy density in the cavity. We derive a quantum inequality bound on the ...

Ford, L H

2009-01-01T23:59:59.000Z

444

Mass limits of charged Higgs boson at large tan. beta. from e sup + e sup minus annihilations at radical s =50--60. 8 GeV  

SciTech Connect

A search for the pair production of charged Higgs particles decaying via the {ital H}{sup {minus}}{r arrow}{tau}{bar {nu}} mode has been made in {ital e}{sup +}{ital e}{sup {minus}} annihilations at center-of-mass energies between 50 and 60.8 GeV using the AMY detector at the KEK collider TRISTAN. No evidence for their existence is observed and 95%-C.L. mass limits are presented. The result has been interpreted in terms of the tan{beta} parameter in the Higgs sector.

Smith, J.R.; McNeil, R.R.; Breedon, R.E.; Kim, G.N.; Ko, W.; Lander, R.L.; Maeshima, K.; Malchow, R.L.; Rowe, J.; Stuart, D.; Imlay, R.; Kirk, P.; Lim, J.; Metcalf, W.; Myung, S.S.; Cheng, C.P.; Gu, P.; Li, J.; Li, Y.K.; Ye, M.H.; Zhu, Y.C.; Abashian, A.; Gotow, K.; Hu, K.P.; Low, E.H.; Mattson, M.E.; Piilonen, L.; Sterner, K.L.; Lusin, S.; Rosenfeld, C.; Wang, A.T.M.; Wilson, S.; Frautschi, M.; Kagan, H.; Kass, R.; Trahern, C.G.; Abe, K.; Fujii, Y.; Higashi, Y.; Kim, S.K.; Kurihara, Y.; Maki, A.; Nozaki, T.; Omori, T.; Sagawa, H.; Sakai, Y.; Sugimoto, Y.; Takaiwa, Y.; Terada, S.; Walker, R.; Kajino, F.; Perticone, D.; Poling, R.; Thomas, T.; Ishi, Y.; Miyano, K.; Miyata, H.; Sasaki, T.; Yamashita, Y.; Bacala, A.; Liu, J.; Park, I.H.; Sannes, F.; Schnetzer, S.; Stone, R.; Vinson, J.; Auchincloss, P.; Blanis, D.; Bodek, A.; Budd, H.; Eno, S.; Fry, C.A.; Harada, H.; Ho, Y.H.; Kim, B.J.; Kim, Y.K.; Kumita, T.; Mori, T.; Olsen, S.L.; Shaw, N.M.; Sill, A.; Thorndike, E.H.; Ueno, K.; Velissa; The AMY Collaboration

1990-08-01T23:59:59.000Z

445

(DDBS) System Doubles Pot Suction, Reduces Roof Emission  

Science Conference Proceedings (OSTI)

... Suction (DDBS) System Doubles Pot Suction, Reduces Roof Emission .... Phase Change Materials in Thermal Energy Storage for Concentrating Solar Power ...

446

System Specification for the Double Shell Tank (DST) System  

Science Conference Proceedings (OSTI)

This document establishes the functional, performance, design, development, interface and test requirements for the Double-Shell Tank System.

GRENARD, C.E.

2000-04-21T23:59:59.000Z