Science.gov

Sample records for radiative decay

  1. Radiative B Decays

    SciTech Connect

    Bard, D.; /Imperial Coll., London

    2011-11-23

    I discuss recent results in radiative B decays from the Belle and BaBar collaborations. I report new measurements of the decay rate and CP asymmetries in b {yields} s{gamma} and b {yields} d{gamma} decays, and measurements of the photon spectrum in b {yields} s{gamma}. Radiative penguin decays are flavour changing neutral currents which do not occur at tree level in the standard model (SM), but must proceed via one loop or higher order diagrams. These transitions are therefore suppressed in the SM, but offer access to poorlyknown SM parameters and are also a sensitive probe of new physics. In the SM, the rate is dominated by the top quark contribution to the loop, but non-SM particles could also contribute with a size comparable to leading SM contributions. The new physics effects are potentially large which makes them theoretically very interesting, but due to their small branching fractions they are typically experimentally challenging.

  2. RADIATIVE PENGUIN DECAYS FROM BABAR

    SciTech Connect

    Eigen, Gerald

    2003-08-28

    Electroweak penguin decays provide a promising hunting ground for Physics beyond the Standard Model (SM). The decay B {yields} X{sub s}{gamma}, which proceeds through an electromagnetic penguin loop, already provides stringent constraints on the supersymmetric (SUSY) parameter space. The present data samples of {approx}1 x 10{sup 8} B{bar B} events allow to explore radiative penguin decays with branching fractions of the order of 10{sup -6} or less. In this brief report they discuss a study of B {yields} K*{ell}{sup +}{ell}{sup -} decay modes and a search for B {yields} {rho}({omega}){gamma} decays.

  3. Radiative Leptonic B Decays

    SciTech Connect

    Chen, Edward Tann

    2007-01-01

    We present the results of a search for B+ meson decays into γℓ+v, where ℓ = e,μ. We use a sample of 232 million B$\\bar{B}$ meson pairs recorded at the Υ(4S) resonance with the BABAR detector at the PEP-II B factory. We measure a partial branching fraction Δβ in a restricted region of phase space that reduces the effect of theoretical uncertainties, requiring the lepton energy to be in the range 1.875 and 2.850 GeV, the photon energy to be in the range 0.45 and 2.35 GeV, and the cosine of the angle between the lepton and photon momenta to be less than -0.36, with all quantities computed in the Υ(4S) center-of-mass frame. We find Δβ(B+ → γℓ+v) = (-0.31.5+1.3(statistical) -0.6+0.6(systematic) ± 0.1(theoretical)) x 10-6, under the assumption of lepton universality. Interpreted as a 90% confidence-level Bayesian upper limit, the result corresponds to 1.7 x 10-6 for a prior at in amplitude, and 2.3 x 10-6 for a prior at in branching fraction.

  4. Radiative decay of nonstationary system.

    PubMed

    Banerjee, Sumana; Gangopadhyay, Gautam

    2004-04-01

    When a finite quantum system, say a fluorescent molecule is attached to a bulk surface and excited by a short laser pulse, the decay dynamics of the system is modulated by the surface and the signal is enhanced due to the bulk surface. We have considered the decay dynamics of a model of displaced distorted molecule whose excited potential surface is coupled to a continuum and then this first continuum is in turn coupled to a second continuum. In the short time scale there is a coherent exchange of energy between the system molecule and the first continuum states. In the long time scale the energy of the whole system plus first continuum drains out to the final continuum states. A dendrimer nanocomposite with the gold surface shows an enhanced light emission. This can be qualitatively understood from the model we proposed here. We have numerically studied the various potential parameters of the molecule which can affect the signal. When the potential surfaces are flat, the band structure of the first continuum states along with its initial excitation has some nontrivial effect on the profile of the radiative decay. PMID:15267501

  5. Weak radiative baryonic decays of B mesons

    SciTech Connect

    Kohara, Yoji

    2004-11-01

    Weak radiative baryonic B decays B{yields}B{sub 1}B{sub 2}-bar{gamma} are studied under the assumption of the short-distance b{yields}s{gamma} electromagnetic penguin transition dominance. The relations among the decay rates of various decay modes are derived.

  6. Radiative Penguin Decays at the B Factories

    SciTech Connect

    Koneke, Karsten; /MIT, LNS

    2007-11-16

    In this article, I review the most recent results in radiative penguin decays from the B factories Belle and BABAR. Most notably, I will talk about the recent new observations in the decays B {yields} ({rho}/{omega}) {gamma}, a new analysis technique in b {yields} s{gamma}, and first measurements of radiative penguin decays in the B{sup 0}{sub s} meson system. Finally, I will summarize the current status and future prospects of radiative penguin B physics at the B factories.

  7. Radiative vacancies decay of endohedral atoms

    NASA Astrophysics Data System (ADS)

    Amusia, Miron; Baltenkov, Arkadiy

    2006-05-01

    It is demonstrated that the fulleren shell affects dramatically the radiative vacancy decay of an endohedral atom A@C60. It also adds new possibilities to radiative and non-radiative decay by opening a number of new interchannel decays similar to that in ordinary atoms where initial and final state vacancies almost always belong to different subshells. We demonstrate that the radiative width of a vacancy decay due to electron transition in the atom A in A@C60 acquire an additional factor that can be expressed via the polarizability of the C60 at transition energy. In general, it can not only enhance but also totally lock the radiative decay channel. For vacancies in subvalent shells of noble gas atoms N the non-radiative decay is forbidden. For N@C60 this decay is allowed since can proceed due to transition of fulleren shell electron to the vacancy in N. Corresponding width is expressed via the C60 total photoabsorption cross-section at the transition energy.

  8. Radiative decay of the free neutron

    SciTech Connect

    Gentile, T. R.; Dewey, M. S.; Fisher, B. M.; Mumm, H. P.; Nico, J. S.; Thompson, A. K.; Chupp, T. E.; Cooper, R. L.; Kremsky, I.; Wietfeldt, F. E.; Beise, E. J.; Breuer, H.; Hood, J.; Kiriluk, K. G.; McGonagle, M.; Byrne, J.; Coakley, K. J.

    2007-10-26

    The theory of quantum electrodynamics predicts that beta decay of the neutron into a proton, electron, and antineutrino should be accompanied by a continuous spectrum of soft photons. We recently reported the first observation of this radiative decay mode of the neutron, measured by recording photons in coincidence with both the electron and proton emitted in neutron decay. The experiment was performed on the NG-6 Fundamental Physics Beam Line at the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR). A new experiment is under development to measure both the branching ratio and energy spectrum for radiative decay with a relative standard uncertainty of a few percent. We briefly review the fundamental neutron physics program at the NCNR and describe the new radiative decay experiment.

  9. Michel parameters in radiative muon decay

    NASA Astrophysics Data System (ADS)

    Arbuzov, A. B.; Kopylova, T. V.

    2016-09-01

    Radiative muon and tau lepton decays are described within the model-independent approach with the help of generalized Michel parameters. The exact dependence on charged lepton masses is taken into account. The results are relevant for modern and future experiments on muon and tau lepton decays.

  10. Electrical Analogs of Atomic Radiative Decay Processes

    ERIC Educational Resources Information Center

    Fontana, Peter R.; Srivastava, Rajendra P.

    1977-01-01

    Analyzes simple electrical circuits, showing that for high frequencies they have frequency and time responses identical to the spontaneous radiative decay of atoms. Compares a two-circuit electrical system with a two-level atom. (MLH)

  11. Radiative And Electroweak Penguin Decays of B

    SciTech Connect

    Richman, Jeffrey D.; /UC, Santa Barbara

    2007-11-09

    Radiative and electroweak penguin decays of B mesons are flavor-changing-neutral-current processes that provide powerful ways to test the Standard Model at the one-loop level, to search for the effects of new physics, and to extract Standard Model parameters such as CKM matrix elements and quark masses. The large data samples obtained by the B-factory experiments BaBar and Belle, together with an intensive theoretical effort, have led to significant progress towards understanding these rare decays. Recent experimental results include the measurements of the b {yields} d{gamma} decays B {yields} {rho}({omega}){gamma}, the observation of B {yields} K(*){ell}{sup +}{ell}{sup -} decays (together with studies of the associated kinematic distributions), and improved measurements of the inclusive B {yields} Xs{gamma} rate and photon energy spectrum.

  12. STUDIES OF RADIATIVE PENGUIN DECAYS AT BABAR

    SciTech Connect

    Jessop, C

    2003-10-27

    The electromagnetic radiative ''penguin'' decays b {yields} s{gamma}, b {yields} d{gamma} are sensitive to physics beyond the Standard Model. The authors present recent studies made with the BABAR detector at the PEP-II asymmetric e{sup +}e{sup -} storage ring.

  13. Penguin diagram dominance in radiative weak decays of bottom baryons

    SciTech Connect

    Kohara, Yoji

    2005-05-01

    Radiative weak decays of antitriplet bottom baryons are studied under the assumption of penguin diagram dominance and flavor-SU(3) (or SU(2)) symmetry. Relations among decay rates of various decay modes are derived.

  14. Biomedical applications of radiative decay engineering

    NASA Astrophysics Data System (ADS)

    Lakowicz, Joseph R.; Gryczynski, Ignacy; Malicka, Joanna; Shen, Yibing; Gryczynski, Zygmunt

    2002-06-01

    Fluorescence spectroscopy is a widely used research tool in biochemistry and has also become the dominant method enabling the revolution in medical diagnostics, DNA sequencing and genomics. In this forward-looking article we describe a new opportunity in fluorescence, radiative decay engineering (RDE). By RDE we mean modifying the emission of fluorophores or chromophores by a nearby metallic surface, the most important effect being an increase in the radiative decay rate. We describe the usual effects expected form increase in the radiative rates with reference to the biomedical applications of immunoassay and DNA hybridization. We also present experiments which show that metallic particles can increase the quantum yield of low quantum yield fluorophores, increase fluorophore photostability and increase the distance for resonance energy transfer. And finally we show that proximity to silver particles can increase the intensity of the intrinsic fluorescence from DNA.

  15. Study of the radiative pion decay

    SciTech Connect

    Chen, Chuan-Hung; Geng, Chao-Qiang; Lih, Chong-Chung

    2011-04-01

    We study the radiative pion decay of {pi}{sup +}{yields}e{sup +}{nu}{sub e}{gamma} in the light-front quark model. We also summarize the result in the chiral perturbation theory. The vector and axial-vector hadronic form factors (F{sub V,A}) for the {pi}{yields}{gamma} transition are evaluated in the whole allowed momentum transfer. In terms of these momentum dependent form factors, we calculate the decay branching ratio and compare our results with the experimental data and other theoretical predictions in the literature. We also constrain the possible size of the tensor interaction in the light-front quark model.

  16. Radiative Decay of Upper Tropospheric Anticyclones

    NASA Astrophysics Data System (ADS)

    Daniel, Vincent; Legras, Bernard

    We investigate the dynamics and the decay of upper tropospheric anticyclones. First, we focus on the nature, the frequency and the formation of these atmospheric patterns. Standard Isentropic Potential Vorticity maps (using analysed fields from ECMWF) show that these synoptic situations are common in the northern hemisphere with a higher frequency during autumn. Massive back-trajectory calculations (using the kinematic trajectory model FLEX- TRA) reveal that most of air parcels are coming from the tropical or the subtropical boundary layer following "warm conveyor belts". Advection of humid air into upper tropospheric anticyclones is in agreement with aircraft data from SONEX and POLI- NAT airborne campaigns and with MOZAIC humidity measurements. In anticyclonic vorticies, these data show frequent relative humidity sursaturation with respect to ice. Mesoscale simulations (using MesoNH model from Meteo-France) has been per- formed to investigate more precisely the advection of boundary layer air into an upper tropospheric anticyclone. Online lagrangian calculations have been performed and we plan to estimate the meridian humidity flux induced by this process. In a second stage, decay of upper tropospheric anticyclones is studied. The presence of thin cirrus clouds in these anticyclonic vortices is an open question. Nevertheless, airborne lidar measurements during the SONEX III campaign show that thin cirrus are present during the first stage of the anticyclone life. These clouds may play a ma- jor role concerning radiative decay. Idealized mesoscale simulations (using MesoNH model) have been performed. At the present time, realistic decay is obtained only in clear sky conditions. Radiative decay induces a net mass flux from the troposphere to the stratosphere. This flux is increased with the moistening of upper tropospheric cy- clones. Using realistic humidity fields, it is found to be of the same order of magnitude that net flux from the stratosphere to the

  17. Form factors in the radiative pion decay

    NASA Astrophysics Data System (ADS)

    Mateu, V.; Portolés, J.

    2007-10-01

    We perform an analysis of the form factors that rule the structure-dependent amplitude in radiative pion decay. The resonance contributions to π→eνeγ decays are computed through the proper construction of the vector and axial-vector form factors by setting the QCD driven asymptotic properties of the three-point Green functions and , and by demanding the smoothening of the form factors at high transfer of momentum. A comparison between theoretical and experimental determination of the form factors is also carried out. We also consider and evaluate the role played by a non-standard tensor form factor. We conclude that, at present and due to the hadronic uncertainties, the search for new physics in this process is not feasible.

  18. QCD challenges in radiative B decays

    SciTech Connect

    Misiak, M.

    2010-12-22

    Radiative decays of the B meson are known to provide important constraints on the MSSM and many other realistic new physics models in the sub-TeV range. The inclusive branching ratio B(B-bar{yields}X{sub s{gamma}}) being the key observable is currently measured to about {+-}7% accuracy. Reaching a better precision on the theory side is a challenge both for the perturbative QCD calculations and for analyses of non-perturbative hadronic effects. The current situation is briefly summarized here.

  19. Inclusive radiative J/{psi} decays

    SciTech Connect

    Besson, D.; Pedlar, T. K.; Cronin-Hennessy, D.; Gao, K. Y.; Hietala, J.; Kubota, Y.; Klein, T.; Lang, B. W.; Poling, R.; Scott, A. W.; Zweber, P.; Dobbs, S.; Metreveli, Z.; Seth, K. K.; Tomaradze, A.; Libby, J.; Powell, A.; Wilkinson, G.; Ecklund, K. M.; Love, W.

    2008-08-01

    Using data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct-photon momentum spectrum in the decay J/{psi}(1S){yields}{gamma}gg, via the ''tagged'' process: e{sup +}e{sup -}{yields}{psi}(2S); {psi}(2S){yields}J/{psi}{pi}{sup +}{pi}{sup -}; J/{psi}{yields}{gamma}+X. Including contributions from two-body radiative decay processes, we find the ratio of the inclusive direct-photon branching fraction to that of the dominant three-gluon branching fraction [R{sub {gamma}}=B(gg{gamma})/B(ggg)] to be R{sub {gamma}}=0.137{+-}0.001{+-}0.016{+-}0.004, where the errors shown are statistical, systematic, and the model-dependent uncertainty related to the extrapolation to zero photon energy. The shape of the scaled photon energy spectrum in J/{psi}{yields}gg{gamma} is observed to be very similar to that of {upsilon}{yields}gg{gamma}. The R{sub {gamma}} value obtained is roughly consistent with that expected by a simple quark-charge scaling [R{sub {gamma}}{approx}(q{sub c}/q{sub b}){sup 2}] of the value determined at the {upsilon}(1S), but somewhat higher than the value expected from the running of the strong coupling constant.

  20. Radiative decays of the neutral Zc(3900 )

    NASA Astrophysics Data System (ADS)

    Chen, Dian-Yong; Dong, Yu-Bing

    2016-01-01

    We study the radiative decays of the Zc(3900 )0 in a hadronic molecule picture, where the Zc(3900 ) is treated as a D D¯ *+c .c hadronic molecule. The partial widths of Γ (Zc(3900 )0→γ ηc(2 S )) and Γ (Zc(3900 )0→γ χc 0) are predicted to be of order 10 keV, and the cross sections for σ (e+e-→π0Zc(3900 )→π0γ ηc(2 S )) and σ (e+e-→π0Zc(3900 )→π0γ χc 0) are of order 0.1 pb at 4.23 GeV, which may be accessible for the BESIII and forthcoming Belle II.

  1. J/psi and UPSILON radiative and hadronic decays

    SciTech Connect

    Bloom, E.D.

    1987-07-01

    The search for gluonium at the J/psi and UPSILON is discussed, as well as the search for exotics at the UPSILON. Reactions discussed include radiative and hadronic decays of the J/psi and the search for radiative decays of the UPSILON. Future perspectives are also briefly considered. 45 refs., 27 figs. (LEW)

  2. T violation in radiative β decay and electric dipole moments

    NASA Astrophysics Data System (ADS)

    Dekens, W.; Vos, K. K.

    2015-12-01

    In radiative β decay, T violation can be studied through a spin-independent T-odd correlation. We consider contributions to this correlation by beyond the standard model (BSM) sources of T-violation, arising above the electroweak scale. At the same time such sources, parametrized by dimension-6 operators, can induce electric dipole moments (EDMs). As a consequence, the manifestations of the T-odd BSM physics in radiative β decay and EDMs are not independent. Here we exploit this connection to show that current EDM bounds already strongly constrain the spin-independent T-odd correlation in radiative β decay.

  3. Radiative decay of massious neutrinos: Implications for physics and astrophysics

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.

    1981-01-01

    The radiative lifetime tau for the decay of massious neutrinos is calculated using various physical models for neutrino decay. The results are related to the astrophysical problem of the detectability of the decay photons from cosmic neutrinos. Conversely, the astrophysical data are used to place lower limits on tau. However, an observed feature at approximately 1700 A in the ultraviolet background radiation at high galactic latitudes may be from the decay of neutrinos with mass approximately 14 eV. This would require a decay rate much larger than the predictions of standard models but could be indicative of a decay rate possible in composite models. It is considered that this may be an important test for substructure in leptons and quarks.

  4. Studies of Radiative Penguin B Decays at BABAR

    SciTech Connect

    Hamel de Monchenault, Gautier

    2003-05-14

    We summarize results on a number of observations of penguin dominated radiative decays of the B meson. Such decays are forbidden at tree level and proceed via electroweak loops. As such they may be sensitive to physics beyond the standard model. The observations have been made at the BaBar experiment at PEPII, the asymmetric B factory at SLAC.

  5. Radiative Corrections for Neutron Decay and Search for New Physics

    PubMed Central

    Gudkov, V.; Kubodera, K.; Myhrer, F.

    2005-01-01

    The expected increased accuracy of neutron β-decay experiments at the new Spallation Neutron Source could result in more stringent tests of the Standard Model. For an unambiguous search for new physics in neutron decay experiments and for a precise determination of fundamental constants, it is necessarily to understand and evaluate all corrections for neutron decay with higher accuracy than the expected experimental precision. We discuss the possibility to estimate the accuracy of radiative corrections. New results based on the applications of effective field theory for neutron decay is presented. PMID:27308143

  6. Dark radiation from particle decay: cosmological constraints and opportunities

    SciTech Connect

    Hasenkamp, Jasper; Kersten, Jörn E-mail: Joern.Kersten@desy.de

    2013-08-01

    We study particle decay as the origin of dark radiation. After elaborating general properties and useful parametrisations we provide model-independent and easy-to-use constraints from nucleosynthesis, the cosmic microwave background and structure formation. Bounds on branching ratios and mass hierarchies depend in a unique way on the time of decay. We demonstrate their power to exclude well-motivated scenarios taking the example of the lightest ordinary sparticle decaying into the gravitino. We point out signatures and opportunities in cosmological observations and structure formation. For example, if there are two dark decay modes, dark radiation and the observed dark matter with adjustable free-streaming can originate from the same decaying particle, solving small-scale problems of structure formation. Hot dark matter mimicking a neutrino mass scale as deduced from cosmological observations can arise and possibly be distinguished after a discovery. Our results can be used as a guideline for model building.

  7. Inclusive radiative {psi}(2S) decays

    SciTech Connect

    Libby, J.; Martin, L.; Powell, A.; Thomas, C.; Wilkinson, G.; Mendez, H.; Ge, J. Y.; Miller, D. H.; Shipsey, I. P. J.; Xin, B.; Adams, G. S.; Hu, D.; Moziak, B.; Napolitano, J.; Ecklund, K. M.; He, Q.; Insler, J.; Muramatsu, H.; Park, C. S.; Thorndike, E. H.

    2009-10-01

    Using e{sup +}e{sup -} collision data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct photon spectrum in the decay {psi}(2S){yields}{gamma}gg. We determine the ratio of the inclusive direct photon decay rate to that of the dominant three-gluon decay rate {psi}(2S){yields}ggg (R{sub {gamma}}{identical_to}{gamma}({gamma}gg)/{gamma}(ggg)) to be R{sub {gamma}}(z{sub {gamma}}>0.4)=0.070{+-}0.002{+-}0.019{+-}0.011, with z{sub {gamma}} defined as the scaled photon energy relative to the beam energy. The errors shown are statistical, systematic, and that due to the uncertainty in the input branching fractions used to extract the ratio, respectively.

  8. Dark radiation from particle decays during big bang nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Menestrina, Justin L.; Scherrer, Robert J.

    2012-02-01

    CMB observations suggest the possibility of an extra dark radiation component, while the current evidence from big bang nucleosynthesis (BBN) is more ambiguous. Dark radiation from a decaying particle can affect these two processes differently. Early decays add an additional radiation component to both the CMB and BBN, while late decays can alter the radiation content seen in the CMB while having a negligible effect on BBN. Here, we quantify this difference and explore the intermediate regime by examining particles decaying during BBN, i.e., particle lifetimes τX satisfying 0.1sec<τX<1000sec. We calculate the change in the effective number of neutrino species, Neff, as measured by the CMB, ΔNCMB, and the change in the effective number of neutrino species as measured by BBN, ΔNBBN, as a function of the decaying particle initial energy density and lifetime, where ΔNBBN is defined in terms of the number of additional two-component neutrinos needed to produce the same change in the primordial He4 abundance as our decaying particle. As expected, for short lifetimes (τX≲0.1sec), the particles decay before the onset of BBN, and ΔNCMB=ΔNBBN, while for long lifetimes (τX≳1000sec), ΔNBBN is dominated by the energy density of the nonrelativistic particles before they decay, so that ΔNBBN remains nonzero and becomes independent of the particle lifetime. By varying both the particle energy density and lifetime, one can obtain any desired combination of ΔNBBN and ΔNCMB, subject to the constraint that ΔNCMB≥ΔNBBN. We present limits on the decaying particle parameters derived from observational constraints on ΔNCMB and ΔNBBN.

  9. Decay processes and radiative cooling of small anionic copper clusters

    NASA Astrophysics Data System (ADS)

    Breitenfeldt, Christian; Blaum, Klaus; Froese, Michael W.; George, Sebastian; Guzmán-Ramírez, Gregorio; Lange, Michael; Menk, Sebastian; Schweikhard, Lutz; Wolf, Andreas

    2016-09-01

    The decay of copper clusters Cun- with size n =4 -7 , produced in a metal ion sputter source, was studied in an electrostatic ion-beam trap. The neutral products after electron emission and fragmentation were monitored for ion storage times of up to a second. The observations indicated the presence of radiative cooling. The energy distributions of the remaining clusters were probed by laser irradiation up to several further seconds of storage time. This defined excitation lead to photoinduced decay signals which, again, showed signs of radiative cooling for Cu6,7 -, not, however, for Cu4,5 -.

  10. Ultraviolet background radiation and the search for decaying neutrinos

    NASA Technical Reports Server (NTRS)

    Henry, R. C.

    1981-01-01

    The spectrum of the observed far-ultraviolet background at high galactic latitudes is studied in order to find evidence of radiation from neutrino decay. It is concluded that at latitudes above about 20 degrees, the limit on any light scattered from interstellar dust or the limit on light from any source other than stars is of order 300 photons/sq cm sec ster A. Superficial evidence for radiation from decaying neutrinos is provided by an examination of the spectrum of the observed background at the highest galactic latitudes, although the spectrum is so uncertain that conclusions are not possible.

  11. Radiative decays, nonet symmetry, and SU(3) breaking

    SciTech Connect

    Benayoun, M.; DelBuono, L.; Eidelman, S.; Ivanchenko, V.N.; Eidelman, S.; Ivanchenko, V.N.; OConnell, H.B.; OConnell, H.B.

    1999-06-01

    We reexamine the problem of simultaneously describing in a consistent way all radiative and leptonic decays of light mesons (V{r_arrow}P{gamma}, P{r_arrow}V{gamma}, P{r_arrow}{gamma}{gamma}, V{r_arrow}e{sup +}e{sup {minus}}). For this purpose, we rely on the hidden local symmetry model in both its anomalous and non-anomalous sectors. We show that the SU(3) symmetry breaking scheme proposed by Bando, Kugo and Yamawaki, supplemented with nonet symmetry breaking in the pseudoscalar sector, allows one to reach a nice agreement with all data, except for the K{sup {asterisk}{plus_minus}} radiative decay. An extension of this breaking pattern allows one to account for this particular decay mode too. Considered together, the whole set of radiative decays provides a pseudoscalar mixing angle {theta}{sub P}{approx_equal}{minus}11{degree} and a value for {theta}{sub V} which is {approx_equal}3{degree} from that of ideal mixing. We also show that it is impossible, in a practical sense, to disentangle the effects of nonet symmetry breaking and those of glue inside the {eta}{sup {prime}}, using only light meson decays. {copyright} {ital 1999} {ital The American Physical Society}

  12. Comparison of two experiments on radiative neutron decay

    NASA Astrophysics Data System (ADS)

    Khafizov, R. U.; Tolokonnikov, S. V.; Solovei, V. A.; Kolhidashvili, M. R.

    2009-12-01

    Over 10 years ago we proposed an experiment on measuring the characteristics of radiative neutron decay in papers [1, 2]. At the same time we had published the theoretical spectrum of radiative gamma quanta, calculated within the framework of the electroweak interactions, on the basis of which we proposed the methodology for the future experiment [3, 4]. However, because we were denied beam time on the intensive cold neutron beam at ILL (Grenoble, France) for a number of years, we could only conduct the experiment in 2005 on the newly opened FRMII reactor of Technical University of Muenchen. The main result of this experiment was the discovery of radiative neutron decay and the measurement of its relative intensity B.R. = (3.2 ± 1.6) × 10-3 with C.L. = 99.7% for radiative gamma quanta with energy over 35 kev [5, 6]. Over a year after our first announcement about the results of the conducted experiment, “Nature” [7] published a letter asserting that its authors have also measured the branching ratio of radiative neutron decay B.R. = (3.13 ± 0.34) × 10-3 with c.l. = 68% and gamma quanta energy from 15 to 340 kev. This article aims to compare these two experiments. It is shown that the use of strong magnetic fields in the NIST (Washington, USA) experiment methodology not only prevents any exact measurement of the branching ratio and identification of radiative neutron decay events, but also makes registration of ordinary neutron decay events impossible.

  13. Polarization effects in radiative decay of a polarized τ lepton

    SciTech Connect

    Gakh, G. I.; Konchatnij, M. I. Korchin, A. Yu.; Merenkov, N. P.

    2015-02-15

    The polarization effects in the one-meson radiative decay of a polarized τ lepton, τ → π{sup −}γν{sub τ}, are investigated. The inner bremsstrahlung and structural amplitudes are taken into account. The asymmetry of the differential decay width caused by the τ-lepton polarization and the Stokes parameters of the emitted photon itself are calculated depending on the polarization of the decaying τ lepton. These physical quantities are estimated numerically for an arbitrary direction of the τ lepton polarization 3-vector in the rest frame. The vector and axial-vector form factors describing the structure-dependent part of the decay amplitude are determined using the chiral effective theory with resonances (RχT)

  14. Radiative neutrino decay in a strong magnetic field

    SciTech Connect

    Anikin, R. A. Mikheev, N. V.

    2013-12-15

    The radiative decay of neutrinos in a strong magnetic field that have relatively high energies, E ≫ m{sub e}, is studied with allowance for positronium contribution to the photon polarization operator in the vicinity of the cyclotron resonance. It is shown that the probability for the process ν → νγ increases substantially upon taking into account the positronium contribution.

  15. Radiative and non radiative decay of electronically excited HNF (DNF)

    SciTech Connect

    Chen, J.; Dagdigian, P.J.

    1993-12-31

    Laser experiments probing the dynamics of the decay of electronically excited HNF/DNF({tilde A}{sup 2}A`) will be reported. Measured decay lifetimes of individual (J`,K) excited levels revealed the onset of a rapid nonradiative decay process at a threshold energy of 23,800 {+-} 500 cm{sup {minus}1} above the HNF({tilde X}{sup 2}A``) zero-point level. The assignment of this threshold to the predissociation process, HNF/DNF{sup *} {yields} NH/ND(X{sup 3}{Sigma}{sup {minus}}) + F({sup 2}P), has been confirmed by direct observation of the NH/ND fragment. Photofragmentation excitation spectra, which exhibits strong mixing between the excited and ground electronic states, will be presented and discussed.

  16. Decay rate of the second radiation belt.

    PubMed

    Badhwar, G D; Robbins, D E

    1996-01-01

    Variations in the Earth's trapped (Van Allen) belts produced by solar flare particle events are not well understood. Few observations of increases in particle populations have been reported. This is particularly true for effects in low Earth orbit, where manned spaceflights are conducted. This paper reports the existence of a second proton belt and it's subsequent decay as measured by a tissue-equivalent proportional counter and a particle spectrometer on five Space Shuttle flights covering an eighteen-month period. The creation of this second belt is attributed to the injection of particles from a solar particle event which occurred at 2246 UT, March 22, 1991. Comparisons with observations onboard the Russian Mir space station and other unmanned satellites are made. Shuttle measurements and data from other spacecraft are used to determine that the e-folding time of the peak of the second proton belt. It was ten months. Proton populations in the second belt returned to values of quiescent times within eighteen months. The increase in absorbed dose attributed to protons in the second belt was approximately 20%. Passive dosimeter measurements were in good agreement with this value.

  17. {lambda}(1520) {yields} {lambda}{gamma} Radiative-Decay Width

    SciTech Connect

    Vavilov, D.V.; Antipov, Yu.M.; Artamonov, A.V.; Batarin, V.A.; Victorov, V.A.; Golovkin, S.V.; Gorin, Yu.P.; Eroshin, O.V.; Kozhevnikov, A.P.; Konstantinov, A.S.; Kubarovsky, V.P.; Kurshetsov, V.F.; Landsberg, L.G.; Leontiev, V.M.; Molchanov, V.V.; Mukhin, V.A.; Patalakha, D.I.; Petrenko, S.V.; Petrukhin, A.I.; Kolganov, V.Z.

    2005-03-01

    The radiative decay {lambda}(1520) {yields} {lambda}{gamma} was recorded in the exclusive reaction p + N {yields} {lambda}(1520)K{sup +} + N at the SPHINX facility. The branching ratio for this decay and the corresponding partial width were found to be, respectively, Br[{lambda}(1520) {yields} {lambda}{gamma}] = (1.02 {+-} 0.21) x 10{sup -2} and {gamma}[{lambda}(1520) {yields} {lambda}{gamma}] = 159 {+-} 35 keV (the quoted errors are purely statistical, the systematic errors being within 15%)

  18. Radiative decay rates of impurity states in semiconductor nanocrystals

    SciTech Connect

    Turkov, Vadim K.; Baranov, Alexander V.; Fedorov, Anatoly V.; Rukhlenko, Ivan D.

    2015-10-15

    Doped semiconductor nanocrystals is a versatile material base for contemporary photonics and optoelectronics devices. Here, for the first time to the best of our knowledge, we theoretically calculate the radiative decay rates of the lowest-energy states of donor impurity in spherical nanocrystals made of four widely used semiconductors: ZnS, CdSe, Ge, and GaAs. The decay rates were shown to vary significantly with the nanocrystal radius, increasing by almost three orders of magnitude when the radius is reduced from 15 to 5 nm. Our results suggest that spontaneous emission may dominate the decay of impurity states at low temperatures, and should be taken into account in the design of advanced materials and devices based on doped semiconductor nanocrystals.

  19. Limits to the radiative decay of the axion

    NASA Technical Reports Server (NTRS)

    Ressell, M. Ted

    1991-01-01

    An axion with a mass greater than 1 eV should be detectable through its decay into two photons. The astrophysical and cosmological limits which define a small window of allowed axion mass above 3 eV are discussed. A firm upper bound to the axion's mass of M(sub a) less than or equal to 8 eV is derived by considering the effect of decaying axions upon the diffuse extragalactic background radiation and the brightness of the night sky due to axions in the halo of the Milky Way galaxy. The intergalactic light of clusters of galaxies is shown to be an ideal place to search for an emission line arising from the radiative decay of axions. An unsuccessful search for this emission line in three clusters of galaxies is then detailed. Limits to the presence of any intracluster line emission are derived with the result that axions with masses between 3 and 8 eV are excluded by the data, effectively closing this window of axion mass, unless a severe cancellation of axionic decay amplitudes occurs. The intracluster flux limits are then used to constrain the amplitude of any such model dependence.

  20. Quasiclassical description of bremsstrahlung accompanying {alpha} decay including quadrupole radiation

    SciTech Connect

    Jentschura, U. D.; Milstein, A. I.; Terekhov, I. S.; Boie, H.; Scheit, H.; Schwalm, D.

    2008-01-15

    We present a quasiclassical theory of {alpha} decay accompanied by bremsstrahlung with a special emphasis on the case of {sup 210}Po, with the aim of finding a unified description that incorporates both the radiation during the tunneling through the Coulomb wall and the finite energy E{sub {gamma}} of the radiated photon up to E{sub {gamma}}{approx}Q{sub {alpha}}/{radical}({eta}), where Q{sub {alpha}} is the {alpha}-decay Q-value and {eta} is the Sommerfeld parameter. The corrections with respect to previous quasiclassical investigations are found to be substantial, and excellent agreement with a full quantum mechanical treatment is achieved. Furthermore, we find that a dipole-quadrupole interference significantly changes the {alpha}-{gamma} angular correlation. We obtain good agreement between our theoretical predictions and experimental results.

  1. Limits on neutrino radiative decay from SN1987A

    SciTech Connect

    Jaffe, A.H.; Fenimore, E.; Turner, M.S.

    1993-01-01

    The authors calculate limits on the properties of neutrinos using data from gamma ray detectors on the Pioneer Venus Orbiter and Solar Max Mission satellites. A massive neutrino decaying in flight from the supernova would produce gamma rays detectable by these instruments. The lack of such a signal allows us to constrain the mass, radiative lifetime, and branching ratio to photons of a massive neutrino species produced in the supernova.

  2. Limits on neutrino radiative decay from SN1987A

    NASA Technical Reports Server (NTRS)

    Jaffe, Andrew H.; Fenimore, ED; Turner, Michael S.

    1993-01-01

    We calculate limits on the properties of neutrinos using data from gamma ray detectors on the Pioneer Venus Orbiter and Solar Max Mission satellites. A massive neutrino decaying in flight from the supernova would produce gamma rays detectable by these instruments. The lack of such a signal allows us to constrain the mass, radiative lifetime, and branching ratio to photons of a massive neutrino species produced in the supernova.

  3. A search for radiative neutrino decay from supernovae

    NASA Technical Reports Server (NTRS)

    Miller, Richard S.; Svoboda, Robert C.

    1993-01-01

    This document presents the data analysis procedures proposed for use with the COMPTEL instrument aboard the Compton Gamma Ray Observatory (GRO) in the search for radiative neutrino decay from supernovae. The proposed analysis methodology is an extension of a standard procedure used by the COMPTEL team in searching for a variety of source types. We have applied the procedures to a set of simulated data to demonstrate the feasibility of the method to this project.

  4. Neutrino radiative decay in N=1 supergravity theories

    NASA Astrophysics Data System (ADS)

    Degrassi, G.; Masiero, A.

    1988-02-01

    We show that the supersymmetrization of models where neutrinos acquire mass through the see-saw mechanism allows for tau neutrinos heavier than 15-20 MeV to decay radiatively in a cosmologically safe way (i.e. with a lifetime τv<=5×103s). Address after September 1, 1987: Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padua, Italy.

  5. Radiative Decays of Low-Lying Excited-State Hyperons

    SciTech Connect

    Simon Taylor

    2000-05-01

    The quark wave-functions of the lower-lying excited-state hyperons Lambda(1405), Sigma(1385), and Lambda(1520) are not well understood. For example, the Lambda(1405) may not be a regular three-quark state but a {bar K}N molecule. Several competing models have been proposed, but none have been convincingly eliminated. Measuring radiative decays provides a means of discriminating between the models. The radiative branching of ratios are predicted to be small ({approx}1%), but the radiative widths vary by factors of 2-10 from model to model. The existing experimental data is sparse and inconsistent; moreover, the radiative decay of the Sigma(1385) has never been observed before (except for one event). These lower-lying excited state hypersons were produced in a tagged photon-beam experiment in the CLAS detector at TJNAF in the reaction gamma p {yields} K{sup +} Y* for photon energies from threshold to 2.4 GeV. The radiative branching ration for the Sigma{sup 0}(1385) relative to the Sigma{sup 0}(1385) {yields} Lambda pi{sup 0} channel was measured to be 0.021 {+-} 0.008{sub -0.007}{sup +0.004}, corresponding to a partial width of 640 {+-} 270{sub -220}{sup +130} keV.

  6. A search for narrow states in radiative upsilon decays

    SciTech Connect

    Lowe, S.T.

    1986-12-01

    A search for new states produced in radiative UPSILON(1S) decays is accomplished by observing the inclusive photon energy spectrum. A narrow resonance in the energy spectrum indicates the existence of a new state X produced by the process UPSILON ..-->.. ..gamma..X. The analysis is based on approximately 0.44 x 10/sup 6/ UPSILON(1S) events produced at the DORIS II e/sup +/e/sup -/ storage ring. These data were collected with the Crystal Ball detector between April 1983 and May 1986. This analysis finds no evidence for a new state, so upper limits on the branching ratio BR(UPSILON ..-->.. ..gamma..X) are derived, assuming the state X decays primarily to high-multiplicity hadronic final states. In particular, if the state X were a minimal Higgs particle, its primary decay mode would be to the heaviest fermion-antifermion pair energetically available. For the radiative UPSILON(1S) decays studied here, the heavy fermions would be c anti c or s anti s quark states, over most of the relevant Higgs' mass range. The resulting upper limit for BR(UPSILON(1S) ..-->.. ..gamma..X) is highly energy dependent but for X mass between 1.5 GeV and 8.0 GeV, the 90% confidence level upper limit is better than 8.0 x 10/sup -4/. For a Higgs' mass near 5.0 GeV, the upper limit is about 2.0 x 10/sup -4/ which is approximately equal to the lowest order calculation for the Wilczek mechanism. The Wilczek calculation with QCD radiative corrections predict branching ratios below the limits set here for all Higgs' masses.

  7. Factorization for radiative heavy quarkonium decays into scalar Glueball

    NASA Astrophysics Data System (ADS)

    Zhu, Ruilin

    2015-09-01

    We establish the factorization formula for scalar Glueball production through radiative decays of vector states of heavy quarkonia, e.g. J/ ψ, ψ(2 S) and Υ( nS), where the Glueball mass is much less than the parent heavy quarkonium mass. The factorization is demonstrated explicitly at one-loop level through the next-to-leading order (NLO) corrections to the hard kernel, the non-relativistic QCD (NRQCD) long-distance matrix elements (LDMEs) of the heavy quarkonium, and the light-cone distribution amplitude (LCDA) of scalar Glueball. The factorization provides a comprehensive theoretical approach to investigate Glueball production in the radiative decays of vector states of heavy quarkonia and determine the physic nature of Glueball. We discuss the scale evolution equation of LCDA for scalar Glueball. In the end, we extract the value of the decay constant of Scalar Glueball from Lattice QCD calculation and analyze the mixing effect among f 0(1370), f 0(1500) and f 0(1710).

  8. Hybrid structure of X(3872) and its radiative decays

    NASA Astrophysics Data System (ADS)

    Takizawa, Makoto; Shimizu, Kiyotaka; Takeuchi, Sachiko

    2014-09-01

    We study the radiative decays of the X (3872) using a charmonium-two-meson hybrid model with the two-meson states consisting of the D0 D *0 , D+D*- , J / Φρ , and J / Φω . We can reproduce the observed mass of the X(3872) in this framework. The obtained structure of the X (3872) explains many of the observed properties, such as the isospin symmetry breaking, the production rate in the p p collision, a lack of the existence of the χc 1 (2 P) peak predicted by the quark model and the absence of the charged partner of the X (3872) . We shall report the results of the X (3872) --> J / Φ γ and X (3872) -->Φ' γ decay rates in our approach.

  9. A search for radiative neutrino decay from supernovae

    NASA Technical Reports Server (NTRS)

    Svoboda, Robert C.

    1993-01-01

    Two supernovae have been identified in the COMPTEL data base as being the best sources to investigate for evidence of gamma-ray emission caused by radiative neutrino decay. These are SN1987a and SN1993J. A detailed simulation has shown us that we can expect a gain in sensitivity 1-3 orders of magnitude (depending on neutrino mass) over previous results. Instrument response is now being modeled using a SPARC10 computer acquired for this study. A library of simulated gamma-ray lines is being produced for COMPTEL as a by-product of this effort.

  10. Lageos orbit decay due to infrared radiation from earth

    NASA Technical Reports Server (NTRS)

    Rubincam, David Parry

    1987-01-01

    Infrared radiation from the earth may be the principal reason for the decay of Lageos' orbit. The radiation heats up the laser retroreflectors embedded in Lageos' aluminum surface. This creates a north-south temperature gradient on the satellite. The gradient in turn causes a force to be exerted on Lageos because of recoil from photons leaving its surface. The delayed heating of the retroreflectors due to their thermal inertia gives the force a net along-track component which always acts like drag. A simple thermal model for the retroreflectors indicates that this thermal drag accounts for about half the observed average along-track acceleration of -3.3 x 10 to the -10th power m/sec squared. The contribution from the aluminum surface to this effect is negligible. The infrared effect cannot explain the large observed fluctuations in drag which occur mainly when the orbit intersects the earth's shadow.

  11. Lageos orbit decay due to infrared radiation from Earth

    NASA Technical Reports Server (NTRS)

    Rubincam, David Parry

    1987-01-01

    Infrared radiation from the Earth may be the principal reason for the decay of Lageos' orbit. The radiation heats up the laser retroreflectors embedded in Lageos' aluminum surface. This creates a north-south temperature gradient on the satellite. The gradient in turn causes a force to be exerted on Lageos because of recoil from photons leaving its surface. The delayed heating of the retroreflectors due to their thermal inertia gives the force a net along-track component which always acts like drag. A simple thermal model for the retroreflectors indicates that this thermal drag accounts for about half the observed average along-track acceleration of -3.3 x 10 to the -10 power m/sec squared. The contribution from the aluminum surface to this effect is negligible. The infrared effect cannot explain the large observed fluctuations in drag which occur mainly when the orbit intersects the Earth's shadow.

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

    SciTech Connect

    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.

    2012-02-16

    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}.

  13. Leptonic radiative decay in supersymmetry without R parity

    SciTech Connect

    Chen, C.-Y.; Kong, Otto C. W.

    2009-06-01

    We present a detailed analysis together with exact numerical calculations on one-loop contributions to the branching ratio of the radiative decay of {mu} and {tau}, namely {mu}{yields}e{gamma}, {tau}{yields}e{gamma}, and {tau}{yields}{mu}{gamma} from supersymmetry without R parity, focusing on contributions involving bilinear couplings. A numerical study is performed to obtain explicit bounds on the parameters under the present experimental limit. We present, and use in the calculation, formulas for exact mass eigenstate effective couplings. In this sense, we present an exact analysis free from approximation for the first time. After comparing our results against the closest early analysis, we discovered a major difference in resulted constraints on some {mu}{sub i}*B{sub j} combinations. Constraints from neutrino masses on the parameters were considered. Our result indicates that the branching ratio measurement on {mu}{yields}e{gamma} down to 10{sup -13}-10{sup -14} and beyond, as targeted by the MEG experiment, has a chance of observing decay from the R-parity violating scenario.

  14. Radiative β decay for studies of CP violation

    NASA Astrophysics Data System (ADS)

    Gardner, Susan; He, Daheng

    2013-06-01

    A triple-product correlation in the radiative β decay rate of neutrons or of nuclei, characterized by the kinematical variable ξ≡(lν×le)·k, where, e.g., n(p)→p(p')+e-(le)+ν¯e(lν)+γ(k), can be generated by the pseudo-Chern-Simons term found by Harvey, Hill, and Hill as a consequence of the baryon vector current anomaly and SU(2)L×U(1)Y gauge invariance at low energies. The correlation probes the imaginary part of its coupling constant, so that its observation at anticipated levels of sensitivity would reflect the presence of sources of CP violation beyond the standard model. We compute the size of the asymmetry in n→pe-ν¯eγ decay in chiral effective theory, compare it with the computed background from standard-model final-state interactions, and consider the new physics scenarios which would be limited by its experimental study.

  15. Radiative Beta Decay for Studies of CP Violation

    NASA Astrophysics Data System (ADS)

    Gardner, Susan; He, Daheng

    2013-10-01

    A triple-product correlation in the radiative β decay rate of neutrons or of nuclei, characterized by the kinematical variable, where, e.g., n (p) --> p (p') +e- (le) + νe (lν) + γ (k) , can be generated by the pseudo-Chern-Simons term found by Harvey, Hill, and Hill as a consequence of the baryon vector current anomaly and SU(2)L ×U(1)Y gauge invariance at low energies. The correlation probes the imaginary part of its coupling constant, so that its observation at anticipated levels of sensitivity would reflect the presence of sources of CP violation beyond the standard model. We compute the size of the asymmetry in n --> pe-νe γ decay in chiral effective theory, compare it with the computed background from standard-model final-state interactions, and consider the new physics scenarios which would be limited by its experimental study. Work supported in part by the U.S. Department of Energy Office of Nuclear Physics under contract no. DE-FG02-96ER40989.

  16. Reexamination of evidence for a radiatively decaying neutrino

    NASA Technical Reports Server (NTRS)

    Murthy, J.; Henry, R. C.

    1987-01-01

    Large-aperture low-dispersion exposures obtained with the IUE short-wavelength camera have been reanalyzed to examine the possibility of using nonstandard electroweak models to explain the steplike signal of 5-sigma significance in the cosmic background claimed by Auriemma et al. (1985). The present results show that no evidence yet exists for the postulated cosmic UV radiation from neutrino decay. Error bars of the order of 20,000 photons/sq cm per s per A per sr are found for the brightnesses of Auriemma et al., and it is suggested that their steps may be due to fixed pattern noise in the detector rather than to a cosmic signal.

  17. Radiative B decays in supersymmetry without R parity

    SciTech Connect

    Kong, Otto C.W.; Vaidya, Rishikesh D.

    2005-03-01

    We present a systematic analysis of all the contributions at the leading log order to the branching ratio of the inclusive radiative decay B{yields}X{sub s}+{gamma} in the framework of supersymmetry without R parity. The relevant set of four-quark operators involved in QCD running are extended from six (within the standard model and the minimal supersymmetric standard model) to 24, with also many new contributions to the Wilson coefficients of (chromo)magnetic penguins for either chiral structure. We present complete analytical results here without any a priori assumptions on the form of R-parity violation. Mass-eigenstate expressions are given; hence the results are free from the commonly adopted mass-insertion approximation. In the numerical analysis, we focus here only on the influence of the trilinear {lambda}{sub ijk}{sup '} couplings and report on the possibility of a few orders of magnitude improvement for the bounds on a few combinations of the {lambda}{sup '} couplings. Our study shows that the Wilson coefficients of the current-current operators due to R-parity violation dominate over the direct contributions to the penguins. However, the interplay of various contributions is complicated due to the QCD corrections which we elaborate here.

  18. Astrophysical tests for radiative decay of neutrinos and fundamental physics implications

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.; Brown, R. W.

    1981-01-01

    The radiative lifetime tau for the decay of massious neutrinos was calculated using various physical models for neutrino decay. The results were then related to the astrophysical problem of the detectability of the decay photons from cosmic neutrinos. Conversely, the astrophysical data were used to place lower limits on tau. These limits are all well below predicted values. However, an observed feature at approximately 1700 A in the ultraviolet background radiation at high galactic latitudes may be from the decay of neutrinos with mass approximately 14 eV. This would require a decay rate much larger than the predictions of standard models but could be indicative of a decay rate possible in composite models or other new physics. Thus an important test for substructure in leptons and quarks or other physics beyond the standard electroweak model may have been found.

  19. Radiation issues in a radioactive ion decay ring.

    PubMed

    Magistris, M; Silari, M

    2005-01-01

    In a beta-beam facility, a pure beam of electron neutrinos, or their antiparticles, are produced by the decay of fully stripped radioactive ions (6He and 18Ne) circulating in a storage ring. Since the beam is not extracted from the ring, all the particles will eventually be lost somewhere in the machine and thus activate the accelerator components and the surrounding concrete and rock. In particular, as nuclei change their charge in beta-decay, a large part of the particles will be lost in the arcs of the decay ring and mainly irradiate the magnets. The density of inelastic interactions of hadrons in the magnets, concrete and rock and the track-length distribution of secondary hadrons were calculated by means of the FLUKA Monte Carlo code. These values were used to estimate the induced radioactivity in the facility, the dose rates expected in the decay ring and the consequences for the environment.

  20. Nuclear Decay Data in the MIRD (Medical Internal Radiation Dose) Format

    DOE Data Explorer

    MIRD is a database of evaluated nuclear decay data for over 2,100 radioactive nuclei. Data are extracted from ENSDF, processed by the program RadList, and used for medical internal radiation dose calculations. When using the MIRD interface, tables of nuclear and atomic radiations from nuclear decay and decay scheme drawings will be produced in the MIRD format from the Evaluated Nuclear Structure Data File (ENSDF) for the specified nuclide. Output may be either HTML-formatted tables and JPEG drawings, PostScript tables and drawings, or PDF tables and drawings.

  1. Activated barrier crossing dynamics in the non-radiative decay of NADH and NADPH

    NASA Astrophysics Data System (ADS)

    Blacker, Thomas S.; Marsh, Richard J.; Duchen, Michael R.; Bain, Angus J.

    2013-08-01

    In live tissue, alterations in metabolism induce changes in the fluorescence decay of the biological coenzyme NAD(P)H, the mechanism of which is not well understood. In this work, the fluorescence and anisotropy decay dynamics of NADH and NADPH were investigated as a function of viscosity in a range of water-glycerol solutions. The viscosity dependence of the non-radiative decay is well described by Kramers and Kramers-Hubbard models of activated barrier crossing over a wide viscosity range. Our combined lifetime and anisotropy analysis indicates common mechanisms of non-radiative relaxation in the two emitting states (conformations) of both molecules. The low frequencies associated with barrier crossing suggest that non-radiative decay is mediated by small scale motion (e.g. puckering) of the nicotinamide ring. Variations in the fluorescence lifetimes of NADH and NADPH when bound to different enzymes may therefore be attributed to differing levels of conformational restriction upon binding.

  2. First Results in Inclusive Radiative Penguin Decays at BABAR

    SciTech Connect

    Jessop, Colin P

    2000-11-17

    We present a preliminary measurement of the branching fraction of the exclusive penguin decay B{sup 0} {yields} K*{sub {gamma}}{sup 0} using (8.6 {+-} 0.3) x 10{sup 6} B{bar B} decays B(B{sup 0} {yields} K*{sub {gamma}}{sup 0}) = (5.42 {+-} 0.82(stat.) {+-} 0.47(sys.)) x 10{sup -5}. In addition they search for the related penguin decays with a lepton pair in the final state, B{sup +} {yields} K{sup +}{ell}{sup +}{ell}{sup -}, B{sup 0} {yields} K*{sup 0} {ell}{sup +}{ell}{sup -}.

  3. Search for hadronic decays of a light Higgs boson in the radiative decay Υ→γA0.

    PubMed

    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; So, R Y; Khan, A; Blinov, V E; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Yushkov, A N; Bondioli, M; Kirkby, D; Lankford, A J; Mandelkern, M; Stoker, D P; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Campagnari, C; Hong, T M; Kovalskyi, D; Richman, J D; West, C A; Eisner, A M; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Cheng, C H; Doll, D A; Echenard, B; Flood, K T; Hitlin, D G; Ongmongkolkul, P; Porter, F C; Rakitin, A Y; Andreassen, R; Dubrovin, M S; Huard, Z; Meadows, B T; Sokoloff, M D; Sun, L; Bloom, P C; Ford, W T; Gaz, A; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Spaan, B; Kobel, M J; Schubert, K R; Schwierz, R; Bernard, D; Verderi, M; Clark, P J; Playfer, S; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Fioravanti, E; Garzia, I; Luppi, E; Munerato, M; Negrini, M; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Nicolaci, M; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Guido, E; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Bhuyan, B; Prasad, V; Lee, C L; Morii, M; Edwards, A J; Adametz, A; Marks, J; Uwer, U; Bernlochner, F U; Ebert, M; Lacker, H M; Lueck, T; Dauncey, P D; Tibbetts, M; Behera, P K; Mallik, U; Chen, C; Cochran, J; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Guo, Z J; Arnaud, N; Davier, M; Grosdidier, G; Le Diberder, F; Lutz, A M; Malaescu, B; Roudeau, P; Schune, M H; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Chavez, C A; Coleman, J P; Fry, J R; Gabathuler, E; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Hafner, A; Prencipe, E; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; Behn, E; Cenci, R; Hamilton, B; Jawahery, A; Roberts, D A; Simi, G; Dallapiccola, C; Cowan, R; Dujmic, D; Sciolla, G; Lindemann, D; Patel, P M; Robertson, S H; Schram, M; Biassoni, P; Lazzaro, A; Lombardo, V; Neri, N; Palombo, F; Stracka, S; Cremaldi, L; Godang, R; Kroeger, R; Sonnek, P; Summers, D J; Nguyen, X; Taras, P; De Nardo, G; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Honscheid, K; Kass, R; Brau, J; Frey, R; Sinev, N B; Strom, D; Torrence, E; Feltresi, E; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Akar, S; Ben-Haim, E; Bomben, M; Bonneaud, G R; Briand, H; Calderini, G; Chauveau, J; Hamon, O; Leruste, Ph; Marchiori, G; Ocariz, J; Sitt, S; Biasini, M; Manoni, E; Pacetti, S; Rossi, A; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Casarosa, G; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Oberhof, B; Paoloni, E; Perez, A; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Piredda, G; Bünger, C; Grünberg, O; Hartmann, T; Leddig, T; Schröder, H; Waldi, R; Adye, T; Olaiya, E O; Wilson, F F; Emery, S; Hamel de Monchenault, G; Vasseur, G; Yèche, Ch; Aston, D; Bard, D J; Bartoldus, R; Benitez, J F; Cartaro, C; Convery, M R; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Franco Sevilla, M; Fulsom, B G; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Lewis, P; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Muller, D R; Neal, H; Nelson, S; Ofte, I; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Snyder, A; Su, D; Sullivan, M K; Va'vra, J; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Young, C C; Ziegler, V; Park, W; Purohit, M V; White, R M; Wilson, J R; Randle-Conde, A; Sekula, S J; Bellis, M; Burchat, P R; Miyashita, T S; Alam, M S; Ernst, J A; Gorodeisky, R; Guttman, N; Peimer, D R; Soffer, A; Lund, P; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Wray, B C; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Lanceri, L; Vitale, L; Martinez-Vidal, F; Oyanguren, A; Ahmed, H; Albert, J; Banerjee, Sw; Choi, H H F; King, G J; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Tasneem, N; Gershon, T J; Harrison, P F; Latham, T E; Puccio, E M T; Band, H R; Dasu, S; Pan, Y; Prepost, R; Wu, S L

    2011-11-25

    We search for hadronic decays of a light Higgs boson (A(0)) produced in radiative decays of an Υ(2S) or Υ(3S) meson, Υ→γA(0). The data have been recorded by the BABAR experiment at the Υ(3S) and Υ(2S) center-of-mass energies and include (121.3±1.2)×10(6) Υ(3S) and (98.3±0.9)×10(6) Υ(2S) mesons. No significant signal is observed. We set 90% confidence level upper limits on the product branching fractions B(Υ(nS)→γA(0))B(A(0)→hadrons) (n=2 or 3) that range from 1×10(-6) for an A(0) mass of 0.3 GeV/c(2) to 8×10(-5) at 7 GeV/c(2). PMID:22182022

  4. Radiative decay of neutron-unbound intruder states in 19O

    NASA Astrophysics Data System (ADS)

    Dungan, R.; Tabor, S. L.; Tripathi, Vandana; Volya, A.; Kravvaris, K.; Abromeit, B.; Caussyn, D. D.; Morrow, S.; Parker, J. J.; Tai, P.-L.; VonMoss, J. M.

    2016-02-01

    The 9Be(14C, α γ ) reaction at EL a b=30 and 35 MeV was used to study excited states of 19O. The Florida State University (FSU) γ detector array was used to detect γ radiation in coincidence with charged particles detected and identified with a silicon Δ E -E particle telescope. γ decays have been observed for the first time from six states ranging from 368 to 2147 keV above the neutron separation energy (Sn=3962 keV) in 19O. The γ -decaying states are interspersed among states previously observed to decay by neutron emission. The ability of electromagnetic decay to compete successfully with neutron decay is explained in terms of neutron angular momentum barriers and small spectroscopic factors implying higher spin and complex structure for these intruder states. These results illustrate the need for complementary experimental approaches to best illuminate the complete nuclear structure.

  5. New Measurement of the π0 radiative decay width.

    PubMed

    Larin, I; McNulty, D; Clinton, E; Ambrozewicz, P; Lawrence, D; Nakagawa, I; Prok, Y; Teymurazyan, A; Ahmidouch, A; Asratyan, A; Baker, K; Benton, L; Bernstein, A M; Burkert, V; Cole, P; Collins, P; Dale, D; Danagoulian, S; Davidenko, G; Demirchyan, R; Deur, A; Dolgolenko, A; Dzyubenko, G; Ent, R; Evdokimov, A; Feng, J; Gabrielyan, M; Gan, L; Gasparian, A; Gevorkyan, S; Glamazdin, A; Goryachev, V; Gyurjyan, V; Hardy, K; He, J; Ito, M; Jiang, L; Kashy, D; Khandaker, M; Kingsberry, P; Kolarkar, A; Konchatnyi, M; Korchin, A; Korsch, W; Kowalski, S; Kubantsev, M; Kubarovsky, V; Li, X; Martel, P; Matveev, V; Mecking, B; Milbrath, B; Minehart, R; Miskimen, R; Mochalov, V; Mtingwa, S; Overby, S; Pasyuk, E; Payen, M; Pedroni, R; Ritchie, B; Rodrigues, T E; Salgado, C; Shahinyan, A; Sitnikov, A; Sober, D; Stepanyan, S; Stephens, W; Underwood, J; Vasiliev, A; Vishnyakov, V; Wood, M; Zhou, S

    2011-04-22

    High precision measurements of the differential cross sections for π0 photoproduction at forward angles for two nuclei, 12C and 208Pb, have been performed for incident photon energies of 4.9-5.5 GeV to extract the π0→γγ decay width. The experiment was done at Jefferson Lab using the Hall B photon tagger and a high-resolution multichannel calorimeter. The π0→γγ decay width was extracted by fitting the measured cross sections using recently updated theoretical models for the process. The resulting value for the decay width is Γ(π0→γγ)=7.82±0.14(stat)±0.17(syst)  eV. With the 2.8% total uncertainty, this result is a factor of 2.5 more precise than the current Particle Data Group average of this fundamental quantity, and it is consistent with current theoretical predictions. PMID:21599360

  6. A New Measurement of the Pi0 Radiative Decay Width

    SciTech Connect

    Larin, I; Clinton, E; Ambrozewicz, P; Lawrence, D; Nakagawa, I; Prok, Y; Teymurazyan, A; Ahmidouch, A; Baker, K; Benton, L; Bernstein, A M; Burkert, V; Cole, P; Collins, P; Dale, D; Danagoulian, S; Davidenko, G; Demirchyan, R; Deur, A; Dolgolenko, A; Dzyubenko, Georgiy; Ent, R; Evdokimov, A; Feng, J; Gabrielyan, M; Gan, L; Gasparian, A; Gevorkyan, S; Glamazdin, A; Goryachev, V; Gyurjyan, V; Hardy, K; He, J; Ito, M; Jiang, L; Kashy, D; Khandaker, M; Kingsberry, P; Kolarkar, A; Konchatnyi, M; Korsch, W; Kowalski, S; Kubantsev, M; Kubarovsky, V; Li, X; Martel, P; Mecking, B; Milbrath, B; Minehart, R; Miskimen, R; Mochalov, V; Mtingwa, S; Overby, S; Pasyuk, E; Payen, M; Pedroni, R; Ritchie, B; Rodrigues, T E; Salgado, C; Shahinyan, A; Sitnikov, A; Sober, D; Stepanyan, S; Stephens, W; Underwood, J; Vishnyakov, V; Wood, M

    2011-04-01

    High precision measurements of the differential cross sections for $\\pi^0$ photoproduction at forward angles for two nuclei, $^{12}$C and $^{208}$Pb, have been performed for incident photon energies of 4.9 - 5.5 GeV to extract the ${\\pi^0 \\to \\gamma\\gamma}$ decay width. The experiment was done at Jefferson Lab using the Hall~B photon tagger and a high-resolution multichannel calorimeter. The ${\\pi^0 \\to \\gamma\\gamma}$ decay width was extracted by fitting the measured cross sections using recently updated theoretical models for the process. The resulting value for the decay width is $\\Gamma{(\\pi^0 \\to \\gamma\\gamma)} = 7.82 \\pm 0.14 ~({\\rm stat.}) \\pm 0.17 ~({\\rm syst.}) ~{\\rm eV}$. With the 2.8\\% total uncertainty, this result is a factor of 2.5 more precise than the current PDG average of this fundamental quantity and it is consistent with current theoretical predictions.

  7. Radiative decay of keV-mass sterile neutrinos in a strongly magnetized plasma

    NASA Astrophysics Data System (ADS)

    Dobrynina, Alexandra A.; Mikheev, Nicolay V.; Raffelt, Georg G.

    2014-12-01

    The radiative decay of sterile neutrinos with typical masses of 10 keV is investigated in the presence of a strong magnetic field and degenerate plasma. A full account is taken of the strongly modified photon dispersion relation relative to vacuum. The limiting cases of relativistic and nonrelativistic plasma are analyzed. The decay rate in a strongly magnetized plasma as a function of the electron number density is compared with the unmagnetized case. We find that a strong magnetic field suppresses the catalyzing influence of the plasma on the decay rate.

  8. Radiative and Leptonic B-meson Decays from the B-factories

    SciTech Connect

    Walsh, John; /INFN, Pisa

    2011-11-14

    Radiative and leptonic decays of B-mesons represent an excellent laboratory for the search for New Physics. I present here recent results on radiative and leptonic decays from the Belle and BABAR collaborations. Radiative penguin and leptonic B-meson decays are excellent probes for investigating the effects of New Physics. Although current measurements are in agreement with the Standard Model expectations, they are still quite useful for setting bounds on possible NP models. The B {yields} X{sub s}{gamma} and B {yields} {tau}{nu} measurements, for example, put strong constraints on the mass of charged Higgs bosons in Type II two-Higgs double models. The B {yields} X{sub s}{gamma} branching fraction measurements also constrain models with universal extra dimensions.

  9. Pyridinylidene-phenoxide in strong electric fields: controlling orientation, conical intersection, and radiation-less decay.

    PubMed

    Belz, S; Zilberg, S; Berg, M; Grohmann, T; Leibscher, M

    2012-11-26

    Strong electric fields open new routes for the control of radiation-less decay in molecules with conical intersections. Here, we present quantum chemical and quantum dynamical simulations which demonstrate that the radiation-less decay and related photoisomerization of pyridinylidene-phenoxide can be effectively manipulated with strong electric fields by shifting the conical intersection. Moreover, we show the effects of the electric field on the orientation of the molecules and on the photoexcitation and discuss the conditions for which the field induced coupling between rotational and vibronic states can be neglected.

  10. Radiative And Electroweak Penguin Processes in Exclusive B Decays

    SciTech Connect

    Kovalskyi, Dmytro; /UC, Santa Barbara

    2011-06-14

    A review of recent BABAR results on exclusive B {yields} ({rho}/{Omega}){gamma}, B {yields} {pi}l{sup +}l{sup -} and B {yields} K(*) l{sup +}l{sup -} decays is presented. It was found that {bar {Beta}}[B {yields} ({rho}/{omega}){gamma}] = (1.01 {+-} 0.21 {+-} 0.08) x 10{sup -6}, {bar {Beta}}[B{sup +} {yields} {pi}l{sup +}l{sup -}] < 7.9 x 10{sup -8} at 90% C.L., {bar {Beta}}[B {yields} Kl{sup +}l{sup -}] = (0.84 {+-} 0.07 {+-} 0.02) x 10{sup -6} and {bar {Beta}}[B {yields} K*l{sup +}l{sup -}] = (0.78{sub -0.17}{sup +0.19} {+-} 0.11) x 10{sup -6}. it was also found that different asymmetry measurements are consistent with Standard Model expectations. Based on these results an independent estimate of the |V{sub td}/V{sub ts}| matrix element of the CKM matrix is derived to be |V{sub td}/V{sub ts}| = 0.171{sub -0.021-0.014}{sup +0.018+0.017}. A first evidence of B{sup +} {yields} {rho}{sup +}{gamma} decays was found and last year's observation of B{sup 0} {yields} {rho}{sup 0}{gamma} was confirmed.

  11. Spin–flip processes and radiative decay of dark intravalley excitons in transition metal dichalcogenide monolayers

    NASA Astrophysics Data System (ADS)

    Slobodeniuk, A. O.; Basko, D. M.

    2016-09-01

    We perform a theoretical study of radiative decay of dark intravalley excitons in transition metal dichalcogenide monolayers. This decay necessarily involves an electronic spin flip. The intrinsic decay mechanism due to interband spin–flip dipole moment perpendicular to the monolayer plane, gives a rate about 100–1000 times smaller than that of bright excitons. However, we find that this mechanism also introduces an energy splitting due to a local field effect, and the whole oscillator strength is contained in the higher-energy component, while the lowest-energy state remains dark and needs an extrinsic spin–flip mechanism for the decay. Rashba effect due to a perpendicular electric field or a dielectric substrate, gives a negligible radiative decay rate (about 107 times slower than that of bright excitons). Spin flip due to Zeeman effect in a sufficiently strong in-plane magnetic field can give a decay rate comparable to that due to the intrinsic interband spin–flip dipole.

  12. Spin-flip processes and radiative decay of dark intravalley excitons in transition metal dichalcogenide monolayers

    NASA Astrophysics Data System (ADS)

    Slobodeniuk, A. O.; Basko, D. M.

    2016-09-01

    We perform a theoretical study of radiative decay of dark intravalley excitons in transition metal dichalcogenide monolayers. This decay necessarily involves an electronic spin flip. The intrinsic decay mechanism due to interband spin-flip dipole moment perpendicular to the monolayer plane, gives a rate about 100-1000 times smaller than that of bright excitons. However, we find that this mechanism also introduces an energy splitting due to a local field effect, and the whole oscillator strength is contained in the higher-energy component, while the lowest-energy state remains dark and needs an extrinsic spin-flip mechanism for the decay. Rashba effect due to a perpendicular electric field or a dielectric substrate, gives a negligible radiative decay rate (about 107 times slower than that of bright excitons). Spin flip due to Zeeman effect in a sufficiently strong in-plane magnetic field can give a decay rate comparable to that due to the intrinsic interband spin-flip dipole.

  13. Measurement of the radiative decay of polarized muons in the MEG experiment

    NASA Astrophysics Data System (ADS)

    Baldini, A. M.; Bao, Y.; Baracchini, E.; Bemporad, C.; Berg, F.; Biasotti, M.; Boca, G.; Cattaneo, P. W.; Cavoto, G.; Cei, F.; Chiarello, G.; Chiri, C.; de Bari, A.; De Gerone, M.; D'Onofrio, A.; Dussoni, S.; Fujii, Y.; Galli, L.; Gatti, F.; Grancagnolo, F.; Grassi, M.; Graziosi, A.; Grigoriev, D. N.; Haruyama, T.; Hildebrandt, M.; Hodge, Z.; Ieki, K.; Ignatov, F.; Iwamoto, T.; Kaneko, D.; Kang, Tae Im; Kettle, P.-R.; Khazin, B. I.; Khomutov, N.; Korenchenko, A.; Kravchuk, N.; Lim, G. M. A.; Mihara, S.; Molzon, W.; Mori, Toshinori; Mtchedlishvili, A.; Nakaura, S.; Nicolò, D.; Nishiguchi, H.; Nishimura, M.; Ogawa, S.; Ootani, W.; Panareo, M.; Papa, A.; Pepino, A.; Piredda, G.; Pizzigoni, G.; Popov, A.; Renga, F.; Ripiccini, E.; Ritt, S.; Rossella, M.; Rutar, G.; Sawada, R.; Sergiampietri, F.; Signorelli, G.; Tassielli, G. F.; Tenchini, F.; Uchiyama, Y.; Venturini, M.; Voena, C.; Yamamoto, A.; Yoshida, K.; You, Z.; Yudin, Yu. V.

    2016-03-01

    We studied the radiative muon decay {\\upmu }+ → {e}+ {\\upnu }bar{{\\upnu }}{\\upgamma } by using for the first time an almost fully polarized muon source. We identified a large sample (˜ 13,000) of these decays in a total sample of 1.8× 10^{14} positive muon decays collected in the MEG experiment in the years 2009-2010 and measured the branching ratio {B}({\\upmu } → {e} {\\upnu }bar{{\\upnu }}{\\upgamma }) = (6.03± 0.14{(stat.)}± 0.53{(sys.)})× 10^{-8} for E_{e}>45 {MeV} and E_{{\\upgamma }}>40 {MeV}, consistent with the Standard Model prediction. The precise measurement of this decay mode provides a basic tool for the timing calibration, a normalization channel, and a strong quality check of the complete MEG experiment in the search for {\\upmu }+ → {e}+ {\\upgamma } process.

  14. Radiative decays of the Sigma0(1385) and Lambda(1520) hyperons

    SciTech Connect

    Simon Taylor; Gordon Mutchler; CLAS Collaboration

    2005-03-01

    The electromagnetic decays of the {Sigma}{sup 0}(1385) and {Lambda}(1520) hyperons were studied in photon-induced reactions {gamma} p {yields} K{sup +} {Lambda}(1116){gamma} in the CLAS detector at the Thomas Jefferson National Accelerator Facility. We report the first observation of the radiative decay of the {Sigma}{sup 0}(1385) and a measurement of the {Lambda}(1520) radiative decay width. For the {Sigma}{sup 0}(1385) {yields} {Lambda}(1116){gamma} transition, we measured a partial width of 479 {+-} 120(stat){sub -100}{sup +81}(sys) keV, larger than all of the existing model predictions. For the {Lambda}(1520) {yields} {Lambda}(1116){gamma} transition, we obtained a partial width of 167 {+-} 43(stat){sub -12}{sup +26}(sys) keV.

  15. Rare Hadronic and Radiative Penguin B Decays at BaBar

    SciTech Connect

    Willocq, Stephane

    2002-02-07

    We report recent results in the study of rare hadronic and radiative penguin decays of B mesons. These results are based on a sample of 23 million BB pairs collected by the BaBar Collaboration at the SLAC PEP-II e+e- B Factory.

  16. Observation of the eta/sub c/(2980) produced in the radiative decay of the psi'(3684)

    SciTech Connect

    Himel, T.M.; Trilling, G.H.; Abrams, G.S.; Alam, M.S.; Blocker, C.A.; Blondel, A.P.; Boyarski, A.M.; Breidenbach, M.; Burke, D.L.; Carithers, W.C.; Chinowsky, W.; Coles, M.W.; Cooper, S.; Dieterle, W.E.; Dillon, J.B.; Dorenbosch, J.; Dorfan, J.M.; Eaton, M.W.; Feldman, G.J.; Franklin, M.E.B.; Gidal, G.; Goldhaber, G.; Hanson, G.; Hayes, K.G.; Hitlin, D.G.; Hollebeek, R.J.; Innes, W.R.; Jaros, J.A.; Jenni, P.; Johnson, A.D.; Kadyk, J.A.; Lankford, A.J.; Larsen, R.R.; Levi, M.E.; Lueth, V.; Millikan, R.E.; Nelson, M.E.; Pang, C.Y.; Patrick, J.F.; Perl, M.L.; Richter, B.; Roussarie, A.; Scharre, D.L.; Schindler, R.H.; Schwitters, R.F.; Siegrist, J.L.; Strait, J.; Taureg, H.; Tonutti, M.; Vella, E.N.; Vidal, R.A.; Videau, I.; Weiss, J.M.; Zaccone, H.

    1980-10-06

    In a study of psi'(3684) radiative decays with the Mark II detector at SPEAR, the decay sequence psi'..--> gamma..eta/sub c/(2980) is observed, with the eta/sub c/(2980) decaying into several completely reconstructed hadronic modes. A mass M=2980 +- 8 MeV/c/sup 2/ and a width GAMMA<40 MeV/c/sup 2/ (90% confidence level) are obtained, and estimates of some of the decay branching ratios are presented.

  17. Improved Measurement of Inclusive Radiative B-meson decays

    SciTech Connect

    Schuemann, J.; Limosani, A.

    2008-11-23

    We report a fully inclusive measurement of the flavor changing neutral current decay B{yields}X{sub s{gamma}} in the energy range 1.7 GeV{<=}E{sub {gamma}}{sup c.m.s}{<=}2.8 GeV, covering 97% of the total spectrum, where c.m.s is the center of mass system. Using 605 fb{sup -1} of data, we obtain in the rest frame of the B-meson B(B{yields}X{sub s{gamma}}:E{sub {gamma}}{sup B}>1.7 GeV) = (3.31{+-}0.19{+-}0.37{+-}0.01)x10{sup -4}, where the errors are statistical, systematic and from the boost correction needed to transform from the rest frame of the {upsilon}(4S)(c.m.s) to that of the B-meson, respectively. We also measure the first and second moments of the photon energy spectrum as functions of various energy thresholds, which extend down to 1.7 GeV. The results are preliminary.

  18. Rare radiative decays of the B c meson

    NASA Astrophysics Data System (ADS)

    Ju, Wan-Li; Wang, Tianhong; Jiang, Yue; Yuan, Han; Wang, Guo-Li

    2016-08-01

    In this paper, we study the rare radiative processes {B}c\\to {D}{sJ}(*)γ within the Standard Model, where {D}{sJ}(*) stands for the meson {D}s*, {D}s1(2460,2536) or {D}s2*(2573). During the investigations, we consider the contributions from the penguin, annihilation, color-suppressed and color-favored cascade diagrams. Our results show that: (1) the penguin and annihilation contributions are dominant in the branching fractions; (2) for the processes {B}c\\to {D}s*γ and {B}c\\to {D}s1(2460,2536)γ , the effects from the color-suppressed and color-favored cascade diagrams are un-negligible.

  19. Observation of tree-level B decays with ss production from gluon radiation.

    PubMed

    Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Ronan, M T; Tackmann, K; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schroeder, T; Steinke, M; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Williams, D C; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Brandt, T; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Biesiada, J; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Baracchini, E; Bellini, F; Cavoto, G; D'Orazio, A; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Castelli, G; Franek, B; Olaiya, E O; Ricciardi, S; Roethel, W; Wilson, F F; Aleksan, R; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Hryn'ova, T; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Dasu, S; Flood, K T; Hollar, J J; Kutter, P E; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Neal, H

    2008-05-01

    We report on our search for decays proceeding via a tree-level b-->c quark transition in which a gluon radiates into an ss[over ] pair. We present observations of the decays B;{-}-->D_{s};{+}K;{-}pi;{-} and B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and evidence for B;{-}-->D_{s};{+}K;{-}K;{-} and set upper limits on the branching fractions for B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and B;{-}-->D_{s};{+}K;{-}K;{-} using 383x10;{6} Upsilon(4S)-->BB[over ] events collected by the BABAR detector at SLAC. We present evidence that the invariant mass distributions of D_{s};{+}K;{-} pairs from B;{-}-->D_{s};{+}K;{-}pi;{-} decays are inconsistent with the phase-space model, suggesting the presence of charm resonances lying below the D_{s};{+}K;{-} threshold. PMID:18518280

  20. Evaluation of spent fuel isotopics, radiation spectra and decay heat using the scale computational system

    SciTech Connect

    Parks, C.V.; Hermann, O.W.; Ryman, J.C.

    1986-01-01

    In order to be a self-sufficient system for transport/storage cask shielding and heat transfer analysis, the SCALE system developers included modules to evaluate spent fuel radiation spectra and decay heat. The primary module developed for these analyses is ORIGEN-S which is an updated verision of the original ORIGEN code. The COUPLE module was also developed to enable ORIGEN-S to easily utilize multigroup cross sections and neutron flux data during a depletion analysis. Finally, the SAS2 control module was developed for automating the depletion and decay via ORIGEN-S while using burnup-dependent neutronic data based on a user-specified fuel assembly and reactor history. The ORIGEN-S data libraries available for depletion and decay have also been significantly updated from that developed with the original ORIGEN code.

  1. Doorway States As Principal Decay Pathway In 12C(12C,{gamma}) Radiative Capture

    SciTech Connect

    Jenkins, D.G.; Fulton, B.R.; Pearson, J.; Lister, C.J.; Carpenter, M.P.; Freeman, S.J.; Hammond, N.J.; Janssens, R.V.F.; Khoo, T.L.; Lauritsen, T.; Wuosmaa, A.H.; Fallon, P.; Goergen, A.; Macchiavelli, A.O.; McMahan, M.; Haas, F.

    2005-04-05

    The heavy-ion radiative capture reaction, 12C(12C,{gamma}), has been investigated at beam energies around 16 MeV. Three different experiments were performed. Capture cross-sections were obtained by measuring fused 24Mg residues using the FMA at ANL. These were found to significantly exceed values reported earlier. Subsequently, the decay pathways associated with radiative capture were studied in two separate measurements: one with the high-resolution Gammasphere array and a second with a high efficiency BGO array, where gamma rays were recorded in coincidence with 24Mg residues detected at the focal plane of the DRAGON recoil separator at TRIUMF. Both measurements indicate that a substantial fraction of the decay is mediated through high-lying doorway states, possibly associated with the long-predicted shape-isomeric band in 24Mg.

  2. Nonperturbative charming penguin contributions to isospin asymmetries in radiative B decays

    SciTech Connect

    Kim, Chul; Mehen, Thomas; Leibovich, Adam K.

    2008-09-01

    Recent experimental data on the radiative decays B{yields}V{gamma}, where V is a light vector meson, find small isospin violation in B{yields}K*{gamma} while isospin asymmetries in B{yields}{rho}{gamma} are of order 20%, with large uncertainties. Using soft-collinear effective theory, we calculate isospin asymmetries in these radiative B decays up to O(1/m{sub b}), also including O(v{alpha}{sub s}) contributions from nonperturbative charming penguins (NPCP). In the absence of NPCP contributions, the theoretical predictions for the asymmetries are a few percent or less. Including the NPCP can significantly increase the isospin asymmetries for both B{yields}V{gamma} modes. We also consider the effect of the NPCP on the branching ratio and CP asymmetries in B{sup {+-}}{yields}V{sup {+-}}{gamma}.

  3. Observation of the radiative decay J/psi. -->. gamma. eta. pi pi

    SciTech Connect

    Newman-Holmes, C.

    1982-09-01

    The radiative decay J/psi ..-->.. ..gamma.. eta ..pi pi.. has been observed in data taken with the Crystal Ball detector at the SPEAR e/sup +/e/sup -/ storage ring. In addition to the well-known eta', the eta ..pi pi.. mass spectrum shows a broad enhancement centered at approx. 1700 MeV. There is no explicit evidence for the l(1440) in the eta ..pi pi.. mass spectrum.

  4. Theoretical investigation of the mode-specific induced non-radiative decay in 2-pyridone

    NASA Astrophysics Data System (ADS)

    Barbatti, Mario; Aquino, Adélia J. A.; Lischka, Hans

    2008-06-01

    Experiments on 2-pyridone (2PY) [Y. Matsuda, T. Ebata, N. Mikami, J. Chem. Phys. 113 (2000) 573; J.A. Frey, R. Leist, C. Tanner, H.M. Frey, S. Leutwyler, J. Chem. Phys. 125 (2006) 114308] have revealed that specific vibrational bands in the laser-induced fluorescence spectrum are missing in comparison to the fluorescence depletion spectrum. The possibility of mode-induced non-radiative decay has been raised in order to explain the effect. In the present work, this hypothesis is tested by an extensive investigation of the excited-state energy surfaces of 2PY by means of multireference ab initio methods. Several conical intersections have been located and the paths connecting them to the minimum on the S 1 surface have been explored. Mixed quantum-classical dynamics simulations were used to estimate how the bias towards specific modes can modify the non-radiative decay rate. These investigations nicely confirm the proposed mode-induced non-radiative decay mechanism.

  5. Photonic effects on the radiative decay rate and luminescence quantum yield of doped nanocrystals.

    PubMed

    Senden, Tim; Rabouw, Freddy T; Meijerink, Andries

    2015-02-24

    Nanocrystals (NCs) doped with luminescent ions form an emerging class of materials. In contrast to excitonic transitions in semiconductor NCs, the optical transitions are localized and not affected by quantum confinement. The radiative decay rates of the dopant emission in NCs are nevertheless different from their bulk analogues due to photonic effects, and also the luminescence quantum yield (QY, important for applications) is affected. In the past, different theoretical models have been proposed to describe the photonic effects for dopant emission in NCs, with little experimental validation. In this work we investigate the photonic effects on the radiative decay rate of luminescent doped NCs using 4 nm LaPO4 NCs doped with Ce(3+) or Tb(3+) ions in different refractive index solvents and bulk crystals. We demonstrate that the measured influence of the refractive index on the radiative decay rate of the Ce(3+) emission, having near unity QY, is in excellent agreement with the theoretical nanocrystal-cavity model. Furthermore, we show how the nanocrystal-cavity model can be used to quantify the nonunity QY of Tb(3+)-doped LaPO4 NCs and demonstrate that, as a general rule, the QY is higher in media with higher refractive index.

  6. Monte Carlo study of the measurement of the Michel parameters in the radiative decay of the τ at Belle

    NASA Astrophysics Data System (ADS)

    Shimizu, N.; Aihara, H.; Epifanov, D.

    2016-07-01

    Michel parameters are kinematic values defined as bilinear combinations of the coupling terms in the general matrix element of the Fermi interaction where all possible Lorentz-invariant scalar, vector and tensor terms are included. The leptonic τ decays provide an excellent laboratory in which to measure the Michel parameters. Any deviation of these parameters from the Standard Model expectation would indicate New Physics. Two Michel parameters, η bar and ξκ, can only be measured in the radiative leptonic decay. These parameters have previously been measured in the radiative decay of the muon but as yet have not been measured in τ decays. We report the results of a feasibility study of the measurement of η bar and ξκ in radiative leptonic τ decays at Belle and Belle II.

  7. Radiative decays of double heavy baryons in a relativistic constituent three-quark model including hyperfine mixing effects

    SciTech Connect

    Branz, Tanja; Faessler, Amand; Gutsche, Thomas; Lyubovitskij, Valery E.; Oexl, Bettina; Ivanov, Mikhail A.; Koerner, Juergen G.

    2010-06-01

    We study flavor-conserving radiative decays of double-heavy baryons using a manifestly Lorentz covariant constituent three-quark model. Decay rates are calculated and compared to each other in the full theory, keeping masses finite, and also in the heavy quark limit. We discuss in some detail hyperfine mixing effects.

  8. Characterizing the decay of ancient Chinese silk fabrics by microbeam synchrotron radiation diffraction.

    PubMed

    Hermes, A C; Davies, R J; Greiff, S; Kutzke, H; Lahlil, S; Wyeth, P; Riekel, C

    2006-03-01

    Scanning synchrotron radiation microdiffraction with an approximately 1 x 1 microm(2) beam has been used as a novel method for characterizing the decay of several T'ang dynasty (618-907 AD) silk fabrics. The crystalline fraction could be visualized based on beta-sheet 210 reflection intensities, extracted by recursive peak fits from several thousand diffraction patterns recorded during mesh scans. The azimuthal width of the 210 reflection, which is related to the orientation distribution of the crystalline domains within nanofibrils and the macroscopic orientation of the fibers traversed by the beam, was found to be sensitive to the overall state of decay of the fabric. The fine structure of the histogram of azimuthal width was related to the fiber hierarchical microstructure and the fabric morphology. SAXS/WAXS analysis supports the assumption of an initial loss of the random chain network with decay. At a subsequent state of aging, decay proceeds into the nanofibrils and the silk fibers break up into even smaller fractions.

  9. Limits to the radiative decays of neutrinos and axions from gamma-ray observations of SN 1987A

    NASA Technical Reports Server (NTRS)

    Kolb, Edward W.; Turner, Michael S.

    1989-01-01

    Gamma-ray observations obtained by the SMM gamma-ray spectrometer in the energy range 4.1-6.4 MeV are used to provide limits on the possible radiative decay of neutrinos and axions emitted by SN 1987A. For branching ratio values for the radiative decay modes of less than about 0.0001, the present limits are more stringent than those based upon the photon flux from decaying relic neutrinos. The data are also used to set an axion mass limit.

  10. Contribution of Neutron Beta Decay to Radiation Belt Pumping from High Altitude Nuclear Explosion

    SciTech Connect

    Marrs, R

    2002-11-13

    In 1962, several satellites were lost following high altitude nuclear tests by the United States and the Soviet Union. These satellite failures were caused by energetic electrons injected into the earth's radiation belts from the beta decay of bomb produced fission fragments and neutrons. It has been 40 years since the last high altitude nuclear test; there are now many more satellites in orbit, and it is important to understand their vulnerability to radiation belt pumping from nuclear explosions at high altitude or in space. This report presents the results of a calculation of the contribution of neutron beta decay to artificial belt pumping. For most high altitude nuclear explosions, neutrons are expected to make a smaller contribution than fission products to the total trapped electron inventory, and their contribution is usually neglected. However, the neutron contribution may dominate in cases where the fission product contribution is suppressed due to the altitude or geomagnetic latitude of the nuclear explosion, and for regions of the radiation belts with field lines far from the detonation point. In any case, an accurate model of belt pumping from high altitude nuclear explosions, and a self-consistent explanation of the 1962 data, require inclusion of the neutron contribution. One recent analysis of satellite measurements of electron flux from the 1962 tests found that a better fit to the data is obtained if the neutron contribution to the trapped electron inventory was larger than that of the fission products [l]. Belt pumping from high altitude nuclear explosions is a complicated process. Fission fragments are dispersed as part of the ionized bomb debris, which is constrained and guided by the earth's magnetic field. Those fission products that beta decay before being lost to the earth's atmosphere can contribute trapped energetic electrons to the earth's radiation belts. There has been a large effort to develop computer models for the contribution of

  11. Search for f(J)(2220) in radiative J/ψ decays.

    PubMed

    del Amo Sanchez, P; Lees, J P; Poireau, V; Prencipe, E; Tisserand, V; Garra Tico, J; Grauges, E; Martinelli, M; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Hooberman, B; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Tanabe, T; Hawkes, C M; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Hearty, C; Mattison, T S; McKenna, J A; Khan, A; Randle-Conde, A; Blinov, V E; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Yushkov, A N; Bondioli, M; Curry, S; Kirkby, D; Lankford, A J; Mandelkern, M; Martin, E C; Stoker, D P; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Campagnari, C; Hong, T M; Kovalskyi, D; Richman, J D; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Hitlin, D G; Ongmongkolkul, P; Porter, F C; Rakitin, A Y; Andreassen, R; Dubrovin, M S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Jasper, H; Karbach, T M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Schubert, K R; Schwierz, R; Bernard, D; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Fioravanti, E; Franchini, P; Luppi, E; Munerato, M; Negrini, M; Petrella, A; Piemontese, L; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Nicolaci, M; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Guido, E; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Bhuyan, B; Prasad, V; Lee, C L; Morii, M; Adametz, A; Marks, J; Uwer, U; Bernlochner, F U; Ebert, M; Lacker, H M; Lueck, T; Volk, A; Dauncey, P D; Tibbetts, M; Behera, P K; Mallik, U; Chen, C; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; Davier, M; Derkach, D; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lutz, A M; Malaescu, B; Perez, A; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, L; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Chavez, C A; Coleman, J P; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Hafner, A; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Anderson, J; Cenci, R; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Cowan, R; Dujmic, D; Fisher, P H; Sciolla, G; Zhao, M; Lindemann, D; Patel, P M; Robertson, S H; Schram, M; Biassoni, P; Lazzaro, A; Lombardo, V; Palombo, F; Stracka, S; Cremaldi, L; Godang, R; Kroeger, R; Sonnek, P; Summers, D J; Nguyen, X; Simard, M; Taras, P; De Nardo, G; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kass, R; Morris, J P; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Feltresi, E; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Ben-Haim, E; Bonneaud, G R; Briand, H; Calderini, G; Chauveau, J; Hamon, O; Leruste, Ph; Marchiori, G; Ocariz, J; Prendki, J; Sitt, S; Biasini, M; Manoni, E; Rossi, A; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Casarosa, G; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Piredda, G; Renga, F; Hartmann, T; Leddig, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Hamel de Monchenault, G; Vasseur, G; Yèche, Ch; Zito, M; Allen, M T; Aston, D; Bard, D J; Bartoldus, R; Benitez, J F; Cartaro, C; Convery, M R; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Franco Sevilla, M; Fulsom, B G; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Santoro, V; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Sun, S; Suzuki, K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Young, C C; Ziegler, V; Chen, X R; Park, W; Purohit, M V; White, R M; Wilson, J R; Sekula, S J; Bellis, M; Burchat, P R; Edwards, A J; Miyashita, T S; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Guttman, N; Soffer, A; Lund, P; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Wray, B C; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Lanceri, L; Vitale, L; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Choi, H H F; Hamano, K; King, G J; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Latham, T E; Puccio, E M T; Band, H R; Dasu, S; Flood, K T; Pan, Y; Prepost, R; Vuosalo, C O; Wu, S L

    2010-10-22

    We present a search for f(J)(2220) production in radiative J/ψ→γf(J)(2220) decays using 460  fb⁻¹ of data collected with the BABAR detector at the SLAC PEP-II e(+)e⁻ collider. The f(J)(2220) is searched for in the decays to K(+)K⁻ and K(S)⁰K(S)⁰. No evidence of this resonance is observed, and 90% confidence level upper limits on the product of the branching fractions for J/ψ→γf(J)(2220) and f(J)(2220)→K(+)K⁻(K(S)⁰K(S)⁰) as a function of spin and helicity are set at the level of 10⁻⁵, below the central values reported by the Mark III experiment. PMID:21231035

  12. Gamma rays from muons from WIMPs: Implementation of radiative muon decays for dark matter analyses

    NASA Astrophysics Data System (ADS)

    Scaffidi, Andre; Freese, Katherine; Li, Jinmian; Savage, Christopher; White, Martin; Williams, Anthony G.

    2016-06-01

    Dark matter searches in gamma ray final states often make use of the fact that photons can be produced from final state muons. Modern Monte Carlo generators and dark matter codes include the effects of final state radiation from muons produced in the dark matter annihilation process itself, but neglect the O (1 %) radiative correction that arises from the subsequent muon decay. After implementing this correction we demonstrate the effect that it can have on dark matter phenomenology by considering the case of dark matter annihilation to four muons via scalar mediator production. We first show that the AMS-02 positron excess can no longer easily be made consistent with this final state once the Fermi-LAT dwarf limits are calculated with the inclusion of radiative muon decays, and we next show that the Fermi-LAT galactic center gamma excess can be improved with this final state after inclusion of the same effect. We provide code and tables for the implementation of this effect in the popular dark matter code micrOMEGAs, providing a solution for any model producing final state muons.

  13. Exclusive radiative B-meson decays within minimal flavor-violating two-Higgs-doublet models

    NASA Astrophysics Data System (ADS)

    Li, Xin-Qiang; Yang, Ya-Dong; Yuan, Xing-Bo

    2014-03-01

    In the "Higgs basis" for a generic two-Higgs-doublet model, only one doublet gets a nonzero vacuum expectation value and, under the criterion of minimal flavor violation, the other one is fixed to be either color-singlet or color-octet, referred to, respectively, as the type-III and type-C models. Both of them can naturally avoid large FCNC transitions and provide very interesting phenomena in some low-energy processes. In this paper, we study their effects on exclusive radiative B-meson decays due to the exchange of colorless or colored charged Higgs. It is found that while constraints from the branching ratios are slightly weaker than the ones from the inclusive B→Xsγ decay, the isospin asymmetries in exclusive decays provide very complementary bounds on the model parameters. As the two models predict similar corrections to the dipole coefficient C7eff, but similar magnitudes with opposite signs to C8eff, the branching ratios cannot discriminate the two models, and we have to resort to the direct CP and isospin asymmetries of b→s processes, which are more sensitive to C8eff. Due to the CKM factors |λu(d)|˜|λt(d)|, the terms proportional to λu(d) make the observables of b→d processes exhibit a different dependence on the possible new physics phase. In addition, correlations between the various observables in the exclusive B→Vγ and the inclusive B→Xs ,dγ decays are investigated, which could provide further insights into the models with more precise experimental measurements and theoretical predictions for these decays.

  14. Established theory of radiation-induced decay is not generalizable to Bolton-Hunter labeled peptides.

    PubMed

    Doran, Amanda C; Wan, Yieh-Ping; Kopin, Alan S; Beinborn, Martin

    2003-05-01

    Peptide hormones radiolabeled with 125I are widely used for the pharmacological characterization of cognate receptors. As a prerequisite for calculating ligand affinities from competition binding assays, and for estimating receptor densities from such studies, it is necessary to know the concentration of bioactive radioligand that is used in respective experiments. It has been demonstrated previously that radioiodinated peptides undergo decay catastrophe, i.e. disintegration of the radioactive label leads to the concomitant destruction of the carrier peptide. Here, we demonstrate that decay catastrophe does not apply to two peptide hormones that are iodinated by Bolton-Hunter conjugation: cholecystokinin octapeptide and glucagon-like peptide 2. The function of aged samples of these radioligands at corresponding recombinantly expressed receptors was assessed by measuring ligand-induced inositol phosphate production or generation of cyclic AMP, respectively. Both of the tested compounds, although predicted by decay catastrophe to contain little or subthreshold remaining bioactivity, stimulated an unexpectedly high level of receptor-mediated second messenger signaling. Quantitative comparison of observed functions with those of corresponding unlabeled peptides suggested that the bioactivity of each radioligand had been largely conserved despite the radioactive decay of the iodine label. Consistent with an apparent absence of decay catastrophe, we noted that the specific radioactivity, when determined immediately following peptide iodination, was close to the theoretical maximum but exponentially decreased over time. These findings raise the possibility that attachment of a Bolton-Hunter conjugate may shield labeled peptides from radiation-induced damage, a scenario that should be considered when performing radioligand binding experiments.

  15. Radiative decays of the psi prime to all-photon final states

    SciTech Connect

    Lee, R.A.

    1985-06-01

    Results of studies of selected radiative decays of the psi' to charmonium and non-charmonium states which decay into photons are presented. These studies were performed using a sample of 1.8 x 10/sup 6/ produced psi''s collected by the Crystal Ball detector at the SPEAR electron-positron storage ring. The branching ratios of the chi/sub 0/, chi/sub 2/, and eta'/sub c/ to two photons have been measured to be (4.5 +- 2.2 +- 2.0) x 10/sup -4/, (9.5 +- 2.9 +- 4.5) x 10/sup -4/ (first errors statistical, second systematic), and <1 x 10/sup -2/ (90% C.L.). The signal from the decay chain psi' ..-->.. ..gamma..chi/sub 0/, chi/sub 0/ ..-->.. ..pi../sup 0/..pi../sup 0/ has been observed with essentially no background. Using the observed line shape of the radiative photon in this reaction, the full width of the psi/sub 0/ has been found to be 8.8 +- 1.3 +- 1.5 MeV/c/sup 2/. In addition, the branching ratios of the chi/sub 0/ and chi/sub 2/ to ..pi../sup 0/..pi../sup 0/ have been measured to be (3.5 +- 0.3 +- 1.2) x 10/sup -3/ and (1.2 +- 0.2 +- 0.4) x 10/sup -3/; the branching ratios of the chi/sub 0/ and chi/sub 2/ to eta eta have been measured to be (2.8 +- 0.9 +- 1.3) x 10/sup -3/ and (8.4 +- 4.2 +- 4.0) x 10/sup -4/. The decays of the psi' to four non-charmonium states have been investigated. The branching ratios and upper limits of these decays have been normalized to the branching ratios of the corresponding decays from the J/psi which have been measured using a sample of 2.2 x 10/sup 6/ produced J/psi's collected by the Crystal Ball detector. The ratios of the psi' branching ratios to the J/psi branching ratios for the final states ..gamma..eta, ..gamma..eta', ..gamma..theta, and ..gamma..f have been measured to be <1.8%, <2.6%, <10 to 15%, and 9 +- 3%. These results are compared with the theoretical expectations of lowest-order quantum chromodynamics potential models. Substantial disagreement is found between theory and experiment.

  16. Experimental limits on the radiative decay of SN 1987A neutrinos

    NASA Technical Reports Server (NTRS)

    Chupp, Edward L.; Vestrand, W. Thomas; Reppin, Claus

    1989-01-01

    SMM gamma-ray spectrometer data are examined to look for gamma-ray emission coincident with the about-10-s neutrino burst from SN 1987A. The absence of a detectable signal suggests that the energy radiated into MeV gamma rays by neutrino decay (or any other process) is less than 10 to the -10th of that in supernova neutrinos above 9 MeV. The results are used to set a direct limit on the lifetime of any massive neutrino type generated in the core collapse leading to SN 1987A.

  17. Evidence for a narrow massive state in the radiative decays of the Upsilon

    SciTech Connect

    Crystal Ball Collaboration

    1984-07-01

    Evidence is presented for a state, which we call zeta, with a mass M = (8322 +- 8 +- 24) MeV and a line width GAMMA < 80 MeV (90% confidence level) obtained using the Crystal Ball (NaI(Tl) detector at DORIS II. Radiative transitions to this state are observed from about 100,000 UPSILON(1S) decays in two independent sets of data: one in which zeta ..-->.. multiple hadrons, and one which is strongly biased towards zeta ..-->.. 2 low multiplicity jets. The branching ratio to this state from the UPSILON(1S) is of order 0.5%.

  18. A New Decay Path in the {sup 12}C+{sup 16}O Radiative Capture Reaction

    SciTech Connect

    Courtin, S.; Lebhertz, D.; Haas, F.; Beck, C.; Michalon, A.; Salsac, M.-D.; Jenkins, D. G.; Marley, P.; Lister, C. J.

    2009-03-04

    The {sup 12}C({sup 16}O,{gamma}){sup 28}Si radiative capture reaction has been studied at energies close to the Coulomb barrier at Triumf (Vancouver) using the Dragon spectrometer and its associated BGO array. It has been observed that the {gamma} decay flux proceeds mainly via states around 10-11 MeV and via the direct feeding of the {sup 28}Si 3{sub 1}{sup -}(6879 keV) and 4{sub 2}{sup +}(6888 keV) deformed states. A discussion is presented about this selective feeding as well as perspectives for the use of novel detection systems for the study of light heavy-ion radiative capture reactions.

  19. BaBar: sin(2beta) with Charmless and Radiative Decays

    SciTech Connect

    Dujmic, Denis; /SLAC

    2006-02-27

    We present new measurements of time-dependent CP-violation parameters in hadronic penguin decays: B{sup 0} {yields} K{sup +}K{sup -}K{sub L}{sup 0}, K{sub S}{sup 0}{pi}{sup 0}{pi}{sup 0}, K{sub S}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}, {omega}K{sub L}{sup 0}, and a radiative penguin decay B{sup 0} {yields} K{sub S}{sup 0}{pi}{sup 0}{gamma} in a dataset of around 230 {center_dot} 10{sup 6} B{bar B} pairs collected by the BABAR detector at the asymmetric B Factory at SLAC. These CP asymmetry measurements probe for amplitudes beyond the Standard Model in loop-dominated decays of neutral B mesons. While we find a puzzling deviation of CP-asymmetry parameters from predicted values, a full confirmation still awaits more data.

  20. Decay strength distributions in {sup 12}C({sup 12}C,{gamma}) radiative capture

    SciTech Connect

    Jenkins, D. G.; Fulton, B. R.; Marley, P.; Fox, S. P.; Glover, R.; Wadsworth, R.; Watson, D. L.; Courtin, S.; Haas, F.; Lebhertz, D.; Beck, C.; Papka, P.; Rousseau, M.; Sanchez i Zafra, A.; Hutcheon, D. A.; Davis, C.; Ottewell, D.; Pavan, M. M.; Pearson, J.; Ruiz, C.

    2007-10-15

    The heavy-ion radiative capture reaction, {sup 12}C({sup 12}C,{gamma}), has been investigated at energies both on- and off-resonance, with a particular focus on known resonances at E{sub c.m.}=6.0, 6.8, 7.5, and 8.0 MeV. Gamma rays detected in a BGO scintillator array were recorded in coincidence with {sup 24}Mg residues at the focal plane of the DRAGON recoil separator at TRIUMF. In this manner, the relative strength of all decay pathways through excited states up to the particle threshold could be examined for the first time. Isovector M1 transitions are found to be a important component of the radiative capture from the E{sub c.m.}=6.0 and 6.8 MeV resonances. Comparison with Monte Carlo simulations suggests that these resonances may have either J=0 or 2, with a preference for J=2. The higher energy resonances at E{sub c.m.}=7.5 and 8.0 MeV have a rather different decay pattern. The former is a clear candidate for a J=4 resonance, whereas the latter has a dominant J=4 character superposed on a J=2 resonant component underneath. The relationship between these resonances and the well-known quasimolecular resonances as well as resonances in breakup and electrofission of {sup 24}Mg into two {sup 12}C nuclei are discussed.

  1. Measurement of Inclusive Radiative B -Meson Decay B -> X_s gamma

    SciTech Connect

    Ozcan, V.E.; /SLAC /Stanford U., Appl. Phys. Dept.

    2006-01-06

    Radiative decays of the B meson, B {yields} X{sub s}{gamma}, proceed via virtual flavor changing neutral current processes that are sensitive to contributions from high mass scales, either within the Standard Model of electroweak interactions or beyond. In the Standard Model, these transitions are sensitive to the weak interactions of the top quark, and relatively robust predictions of the inclusive decay rate exist. Significant deviation from these predictions could be interpreted as indications for processes not included in the minimal Standard Model, like interactions of charged Higgs or SUSY particles. The analysis of the inclusive photon spectrum from B {yields} X{sub s}{gamma} decays is rather challenging due to high backgrounds from photons emitted in the decay of mesons in B decays as well as e{sup +}e{sup -} annihilation to low mass quark and lepton pairs. Based on 88.5 million B{bar B} events collected by the BABAR detector, the photon spectrum above 1.9 GeV is presented. By comparison of the first and second moments of the photon spectrum with QCD predictions (calculated in the kinetic scheme), QCD parameters describing the bound state of the b quark in the B meson are extracted: m{sub b} = (4.45 {+-} 0.16) GeV/c{sup 2}; {mu}{sub {pi}}{sup 2} = (0.65 {+-} 0.29) GeV{sup 2}. These parameters are useful input to non-perturbative QCD corrections to the semileptonic B decay rate and the determination of the CKM parameter |V{sub ub}|. Based on these parameters and heavy quark expansion, the full branching fraction is obtained as: {Beta}(B {yields} X{sub s}{gamma}){sup E{sub {gamma}}>1.6 GeV} = (4.05 {+-} 0.32(stat) {+-} 0.38(syst) {+-} 0.29(model)) x 10{sup -4}. This result is in good agreement with previous measurements, the statistical and systematic errors are comparable. It is also in good agreement with the theoretical Standard Model predictions, and thus within the present errors there is no indication of any interactions not accounted for in the

  2. Bond Fission and Non-Radiative Decay in Iridium(III) Complexes.

    PubMed

    Zhou, Xiuwen; Burn, Paul L; Powell, Benjamin J

    2016-06-01

    We investigate the role of metal-ligand bond fission in the nonradiative decay of excited states in iridium(III) complexes with applications in blue organic light-emitting diodes (OLEDs). We report density functional theory (DFT) calculations of the potential energy surfaces upon lengthening an iridium-nitrogen (Ir-N) bond. In all cases we find that for bond lengths comparable to those of the ground state the lowest energy state is a triplet with significant metal-to-ligand change transfer character ((3)MLCT). But, as the Ir-N bond is lengthened there is a sudden transition to a regime where the lowest excited state is a triplet with significant metal centered character ((3)MC). Time-dependent DFT relativistic calculations including spin-orbit coupling perturbatively show that the radiative decay rate from the (3)MC state is orders of magnitude slower than that from the (3)MLCT state. The calculated barrier height between the (3)MLCT and (3)MC regimes is clearly correlated with previously measured nonradiative decay rates, suggesting that thermal population of the (3)MC state is the dominant nonradiative decay process at ambient temperature. In particular, fluorination both drives the emission of these complexes to a deeper blue color and lowers the (3)MLCT-(3)MC barrier. If the Ir-N bond is shortened in the (3)MC state another N atom is pushed away from the Ir, resulting in the breaking of this bond, suggesting that once the Ir-N bond breaks the damage to the complex is permanent-this will have important implications for the lifetimes of devices using this type of complex as the active material. The consequences of these results for the design of more efficient blue phosphors for OLED applications are discussed. PMID:27175618

  3. Radiation decay of thaumatin crystals at three X-ray energies

    PubMed Central

    Liebschner, Dorothee; Rosenbaum, Gerold; Dauter, Miroslawa; Dauter, Zbigniew

    2015-01-01

    Radiation damage is an unavoidable obstacle in X-ray crystallographic data collection for macromolecular structure determination, so it is important to know how much radiation a sample can endure before being degraded beyond an acceptable limit. In the literature, the threshold at which the average intensity of all recorded reflections decreases to a certain fraction of the initial value is called the ‘dose limit’. The first estimated D 50 dose-limit value, at which the average diffracted intensity was reduced to 50%, was 20 MGy and was derived from observing sample decay in electron-diffraction experiments. A later X-ray study carried out at 100 K on ferritin protein crystals arrived at a D 50 of 43 MGy, and recommended an intensity reduction of protein reflections to 70%, D 70, corresponding to an absorbed dose of 30 MGy, as a more appropriate limit for macromolecular crystallography. In the macromolecular crystallography community, the rate of intensity decay with dose was then assumed to be similar for all protein crystals. A series of diffraction images of cryocooled (100 K) thaumatin crystals at identical small, 2° rotation intervals were recorded at X-ray energies of 6.33 , 12.66 and 19.00 keV. Five crystals were used for each wavelength. The decay in the average diffraction intensity to 70% of the initial value, for data extending to 2.45 Å resolution, was determined to be about 7.5 MGy at 6.33 keV and about 11 MGy at the two higher energies. PMID:25849388

  4. Measurement of the Radiative Decay of the Longest-Lived Level in the Fe XVII Spectrum

    NASA Astrophysics Data System (ADS)

    Brown, Gregory V.; Beiersdorfer, Peter; Träbert, Elmar

    2014-08-01

    The Fe XVII emission spectrum comprises several very prominent X-ray lines that play an important role in the study of many astrophysical objects. Among the Fe XVII X-ray lines, those emanating from a 3s level, i.e., lines 3F, 3G, and M2, invariably appear too strong compared to the lines emanating from a 3d level, i.e., lines 3C and 3D, when compared to theory. Two of the four 3s levels are metastable, which means they have a rather long radiative decay time compared to collisional processes. The decay rate of the 2p^53s J=2 level has recently been measured at the Livermore EBIT facility [J. R. Crespo López-Urrutia and P. Beiersdorfer, ApJ 721, 576 (2010)], and the scatter of predictions by a factor of 1.7 has been reduced to a measurement uncertainty of merely a few percent. Even longer-lived is the J=0 level of the same 2p^53s configuration. Theory predicts an exclusive magnetic dipole decay to the lowest J=1 level of the same 2p^53s configuration, i.e. to the upper level of line 3G. There appear to be fewer predictions for this rate than for the rates associated with the other Fe XVII levels. Various calculations yield a decay rate near 16 000 s-1 for this level (or a level lifetime near 63 µs). If this value is correct, electron-impact collisions affect line ratios tied to this level at densities between about 10^10 cm-3 and 10^13 cm-3, that is, exactly at many coronal densities of present interest. We have used the Livermore EBIT facility to measure the M1 decay rate of the 2p^53s J=0 level. We find a value commensurate with the value predicted by the Flexible Atomic Code.Work performed under auspices of U.S. D.o.E. by DE-AC52-07NA27344 and supported by NASA's APRA progam under Interagency Agreement NNG13WF991.

  5. Experimental observation of nonspherically-decaying radiation from a rotating superluminal source

    NASA Astrophysics Data System (ADS)

    Ardavan, A.; Hayes, W.; Singleton, J.; Ardavan, H.; Fopma, J.; Halliday, D.

    2004-10-01

    We describe the experimental implementation of a superluminal (i.e., faster than light in vacuo) polarization current distribution that both oscillates and undergoes centripetal acceleration. Theoretical treatments predict that the radiation emitted by each volume element of the superluminally moving distribution pattern will comprise a Čerenkov-like envelope with two sheets that meet along a cusp. Correspondingly, the emission from the experimental machine is found to be tightly beamed in both the azimuthal and polar directions. The beaming is frequency independent and has a sharply defined and unchanging geometry determined only by the speed and path of the moving distribution pattern, i.e., by the parameters governing the structure of the Čerenkov-like envelopes. In addition, over a restricted range of angles, we detect the presence of cusps in the emitted radiation. These, which are due to the focusing of wave fronts on a propagating space curve, result in the reception, during a short time period, of radiation emitted over a considerably longer period of (retarded) source time. The intensity of the radiation at these angles was observed to decline more slowly with increasing distance from the source than would the emission from a conventional antenna. The angular distribution of the emitted radiation and the properties associated with the cusps are in good quantitative agreement with theoretical models of superluminal sources once the effect of reflections from the earth's surface are taken into account. In particular, the prediction that the beaming and the slow decay should extend into the far zone has been tested to several hundred Fresnel distances (Rayleigh ranges). The excellent agreement between the theoretical calculations and the data suggests that the apparatus achieves precise and reproducible control of the polarization current and that similar machines could be of general interest for studying and utilizing the novel effects associated with

  6. Experimental observation of nonspherically-decaying radiation from a rotating superluminal source

    SciTech Connect

    Ardavan, A.; Hayes, W.; Singleton, J.; Ardavan, H.; Fopma, J.; Halliday, D.

    2004-10-15

    We describe the experimental implementation of a superluminal (i.e., faster than light in vacuo) polarization current distribution that both oscillates and undergoes centripetal acceleration. Theoretical treatments predict that the radiation emitted by each volume element of the superluminally moving distribution pattern will comprise a Cerenkov-like envelope with two sheets that meet along a cusp. Correspondingly, the emission from the experimental machine is found to be tightly beamed in both the azimuthal and polar directions. The beaming is frequency independent and has a sharply defined and unchanging geometry determined only by the speed and path of the moving distribution pattern, i.e., by the parameters governing the structure of the Cerenkov-like envelopes. In addition, over a restricted range of angles, we detect the presence of cusps in the emitted radiation. These, which are due to the focusing of wave fronts on a propagating space curve, result in the reception, during a short time period, of radiation emitted over a considerably longer period of (retarded) source time. The intensity of the radiation at these angles was observed to decline more slowly with increasing distance from the source than would the emission from a conventional antenna. The angular distribution of the emitted radiation and the properties associated with the cusps are in good quantitative agreement with theoretical models of superluminal sources once the effect of reflections from the earth's surface are taken into account. In particular, the prediction that the beaming and the slow decay should extend into the far zone has been tested to several hundred Fresnel distances (Rayleigh ranges). The excellent agreement between the theoretical calculations and the data suggests that the apparatus achieves precise and reproducible control of the polarization current and that similar machines could be of general interest for studying and utilizing the novel effects associated with

  7. Measurement of the radiative decay width Γ [ Λ (1520) → Λγ ] with the SPHINX spectrometer

    NASA Astrophysics Data System (ADS)

    Antipov, Yu. M.; Artamonov, A. V.; Batarin, V. A.; Vavilov, D. V.; Victorov, V. A.; Eroshin, O. V.; Golovkin, S. V.; Gorin, Yu. P.; Kolganov, V. Z.; Kozhevnikov, A. P.; Konstantinov, A. S.; Kubarovsky, V. P.; Kurshetsov, V. F.; Landsberg, L. G.; Leontiev, V. M.; Lomkatsi, G. S.; Molchanov, V. V.; Mukhin, V. A.; Nilov, A. F.; Patalakha, D. I.; Petrenko, S. V.; Smolyankin, V. T.; Sphinx Collaboration

    2004-12-01

    The radiative decay Λ (1520) → Λγ was measured directly in the study of the exclusive diffractive-like reaction p + N → Λ (1520)K+ + N, Λ (1520) → Λγ with the SPHINX spectrometer. The values of the branching and partial width of this radiative decay were obtained: BR [ Λ (1520) → Λγ ] = (1.02 ± 0.21 (stat) ± 0.15 (syst)) ×10-2 and Γ [ Λ (1520) → Λγ ] = 159 ± 33 (stat) ± 26 (syst) keV.

  8. Measurement of the radiative decay width Γ[Λ(1520)→Λγ] with the SPHINX spectrometer

    NASA Astrophysics Data System (ADS)

    Sphinx Collaboration; Antipov, Yu. M.; Artamonov, A. V.; Batarin, V. A.; Vavilov, D. V.; Victorov, V. A.; Eroshin, O. V.; Golovkin, S. V.; Gorin, Yu. P.; Kolganov, V. Z.; Kozhevnikov, A. P.; Konstantinov, A. S.; Kubarovsky, V. P.; Kurshetsov, V. F.; Landsberg, L. G.; Leontiev, V. M.; Lomkatsi, G. S.; Molchanov, V. V.; Mukhin, V. A.; Nilov, A. F.; Patalakha, D. I.; Petrenko, S. V.; Smolyankin, V. T.

    2004-12-01

    The radiative decay Λ(1520)→Λγ was measured directly in the study of the exclusive diffractive-like reaction p+N→Λ(1520)K++N, Λ(1520)→Λγ with the SPHINX spectrometer. The values of the branching and partial width of this radiative decay were obtained: BR[Λ(1520)→Λγ]=(1.02±0.21(stat)±0.15(syst))×10-2 and Γ[Λ(1520)→Λγ]=159±33(stat)±26(syst) keV.

  9. Spectral and Non Radiative Decay Studies of Lead Di Bromide Single Crystals by Mode Matched Thermal Lens Technique.

    PubMed

    Rejeena, I; Lillibai, B; Thomas, V; Nampoori, V P N; Radhakrishnan, P

    2016-07-01

    In the present paper, the investigations on the non radiative decay mechanism, optical band gap determination from absorption spectroscopic studies and fluorescence emission by photo luminescence techniques using different excitation wavelengths on gel derived lead di bromide single crystals are reported. Non radiative decay of the sample is studied using high sensitive dual beam mode matched thermal lens technique. For the thermal lensing experiment the crystal in solution phase is incorporated with rhodamine 6G dye for enhancing the absorption of the crystal sample. The thermal diffusivity of lead di bromide is determined using the probe beam intensity v/s time measurements. PMID:27165040

  10. Precision Measurement of the Radiative β Decay of the Free Neutron.

    PubMed

    Bales, M J; Alarcon, R; Bass, C D; Beise, E J; Breuer, H; Byrne, J; Chupp, T E; Coakley, K J; Cooper, R L; Dewey, M S; Gardner, S; Gentile, T R; He, D; Mumm, H P; Nico, J S; O'Neill, B; Thompson, A K; Wietfeldt, F E

    2016-06-17

    The standard model predicts that, in addition to a proton, an electron, and an antineutrino, a continuous spectrum of photons is emitted in the β decay of the free neutron. We report on the RDK II experiment which measured the photon spectrum using two different detector arrays. An annular array of bismuth germanium oxide scintillators detected photons from 14 to 782 keV. The spectral shape was consistent with theory, and we determined a branching ratio of 0.00335±0.00005[stat]±0.00015[syst]. A second detector array of large area avalanche photodiodes directly detected photons from 0.4 to 14 keV. For this array, the spectral shape was consistent with theory, and the branching ratio was determined to be 0.00582±0.00023[stat]±0.00062[syst]. We report the first precision test of the shape of the photon energy spectrum from neutron radiative decay and a substantially improved determination of the branching ratio over a broad range of photon energies. PMID:27367385

  11. Evidence for the eta(b)(1S) meson in radiative Upsilon(2S) decay.

    PubMed

    Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Chaisanguanthum, K S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Godang, R; Kroeger, R; Summers, D J; Zhao, H W; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Del Amo Sanchez, P; Ben-Haim, E; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Miyashita, T S; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; King, G J; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Puccio, E M T; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Prepost, R; Vuosalo, C O; Wu, S L

    2009-10-16

    We have performed a search for the eta_{b}(1S) meson in the radiative decay of the Upsilon(2S) resonance using a sample of 91.6x10(6) Upsilon(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at Egamma=609.3(-4.5)(+4.6)(stat)+/-1.9(syst) MeV, corresponding to an eta(b)(1S) mass of 9394.2(-4.9)(+4.8)(stat)+/-2.0(syst) MeV/c2. The branching fraction for the decay Upsilon(2S)-->gamma(eta)b(1S) is determined to be [3.9+/-1.1(stat)-0.9+1.1(syst)]x10(-4). We find the ratio of branching fractions B[Upsilon(2S)-->gamma(eta)b(1S)]/B[Upsilon(3S)-->gamma(eta)b(1S)]=0.82+/-0.24(stat)(-0.19)(+0.20)(syst).

  12. Evidence for the ηb(1S) Meson in Radiative Υ(2S) Decay

    NASA Astrophysics Data System (ADS)

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lynch, G.; Osipenkov, I. L.; Tackmann, K.; Tanabe, T.; Hawkes, C. M.; Soni, N.; Watson, A. T.; Koch, H.; Schroeder, T.; Asgeirsson, D. J.; Fulsom, B. G.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Barrett, M.; Khan, A.; Randle-Conde, A.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Abachi, S.; Buchanan, C.; Atmacan, H.; Gary, J. W.; Liu, F.; Long, O.; Vitug, G. M.; Yasin, Z.; Zhang, L.; Sharma, V.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Mazur, M. A.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Schalk, T.; Schumm, B. A.; Seiden, A.; Winstrom, L. O.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Fang, F.; Hitlin, D. G.; Narsky, I.; Piatenko, T.; Porter, F. C.; Andreassen, R.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Hirschauer, J. F.; Nagel, M.; Nauenberg, U.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Soffer, A.; Toki, W. H.; Wilson, R. J.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Kobel, M. J.; Nogowski, R.; Schubert, K. R.; Schwierz, R.; Volk, A.; Bernard, D.; Bonneaud, G. R.; Latour, E.; Verderi, M.; Clark, P. J.; Playfer, S.; Watson, J. E.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Franchini, P.; Luppi, E.; Negrini, M.; Petrella, A.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Contri, R.; Lo Vetere, M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Tosi, S.; Chaisanguanthum, K. S.; Morii, M.; Adametz, A.; Marks, J.; Schenk, S.; Uwer, U.; Bernlochner, F. U.; Klose, V.; Lacker, H. M.; Bard, D. J.; Dauncey, P. D.; Tibbetts, M.; Behera, P. K.; Chai, X.; Charles, M. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Dong, L.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Arnaud, N.; Béquilleux, J.; D'Orazio, A.; Davier, M.; Firmino da Costa, J.; Grosdidier, G.; Le Diberder, F.; Lepeltier, V.; Lutz, A. M.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Clarke, C. K.; di Lodovico, F.; Sacco, R.; Sigamani, M.; Cowan, G.; Paramesvaran, S.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Alwyn, K. E.; Bailey, D.; Barlow, R. J.; Jackson, G.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Dallapiccola, C.; Salvati, E.; Saremi, S.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Henderson, S. W.; Sciolla, G.; Spitznagel, M.; Taylor, F.; Yamamoto, R. K.; Zhao, M.; Patel, P. M.; Robertson, S. H.; Lazzaro, A.; Lombardo, V.; Palombo, F.; Bauer, J. M.; Cremaldi, L.; Godang, R.; Kroeger, R.; Summers, D. J.; Zhao, H. W.; Simard, M.; Taras, P.; Nicholson, H.; de Nardo, G.; Lista, L.; Monorchio, D.; Onorato, G.; Sciacca, C.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Corwin, L. A.; Honscheid, K.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Regensburger, J. J.; Sekula, S. J.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Kolb, J. A.; Lu, M.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Castelli, G.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Voci, C.; Del Amo Sanchez, P.; Ben-Haim, E.; Briand, H.; Chauveau, J.; Hamon, O.; Leruste, Ph.; Ocariz, J.; Perez, A.; Prendki, J.; Sitt, S.; Gladney, L.; Biasini, M.; Manoni, E.; Angelini, C.; Batignani, G.; Bettarini, S.; Calderini, G.; Carpinelli, M.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Marchiori, G.; Morganti, M.; Neri, N.; Paoloni, E.; Rizzo, G.; Walsh, J. J.; Lopes Pegna, D.; Lu, C.; Olsen, J.; Smith, A. J. S.; Telnov, A. V.; Anulli, F.; Baracchini, E.; Cavoto, G.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Jackson, P. D.; Li Gioi, L.; Mazzoni, M. A.; Morganti, S.; Piredda, G.; Renga, F.; Voena, C.; Ebert, M.; Hartmann, T.; Schröder, H.; Waldi, R.; Adye, T.; Franek, B.; Olaiya, E. O.; Wilson, F. F.; Emery, S.; Esteve, L.; Hamel de Monchenault, G.; Kozanecki, W.; Vasseur, G.; Yèche, Ch.; Zito, M.; Chen, X. R.; Liu, H.; Park, W.; Purohit, M. V.; White, R. M.; Wilson, J. R.; Allen, M. T.; Aston, D.; Bartoldus, R.; Benitez, J. F.; Cenci, R.; Coleman, J. P.; Convery, M. R.; Dingfelder, J. C.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Field, R. C.; Gabareen, A. M.; Graham, M. T.; Grenier, P.; Hast, C.; Innes, W. R.; Kaminski, J.; Kelsey, M. H.; Kim, H.; Kim, P.; Kocian, M. L.; Leith, D. W. G. S.; Li, S.; Lindquist, B.; Luitz, S.; Luth, V.; Lynch, H. L.; Macfarlane, D. B.; Marsiske, H.; Messner, R.; Muller, D. R.; Neal, H.; Nelson, S.; O'Grady, C. P.; Ofte, I.; Perl, M.; Ratcliff, B. N.; Roodman, A.; Salnikov, A. A.; Schindler, R. H.; Schwiening, J.; Snyder, A.; Su, D.; Sullivan, M. K.; Suzuki, K.; Swain, S. K.; Thompson, J. M.; Va'Vra, J.; Wagner, A. P.; Weaver, M.; West, C. A.; Wisniewski, W. J.; Wittgen, M.; Wright, D. H.; Wulsin, H. W.; Yarritu, A. K.; Yi, K.; Young, C. C.; Ziegler, V.; Burchat, P. R.; Edwards, A. J.; Miyashita, T. S.; Ahmed, S.; Alam, M. S.; Ernst, J. A.; Pan, B.; Saeed, M. A.; Zain, S. B.; Spanier, S. M.; Wogsland, B. J.; Eckmann, R.; Ritchie, J. L.; Ruland, A. M.; Schilling, C. J.; Schwitters, R. F.; Drummond, B. W.; Izen, J. M.; Lou, X. C.; Bianchi, F.; Gamba, D.; Pelliccioni, M.; Bomben, M.; Bosisio, L.; Cartaro, C.; Della Ricca, G.; Lanceri, L.; Vitale, L.; Azzolini, V.; Lopez-March, N.; Martinez-Vidal, F.; Milanes, D. A.; Oyanguren, A.; Albert, J.; Banerjee, Sw.; Bhuyan, B.; Choi, H. H. F.; Hamano, K.; King, G. J.; Kowalewski, R.; Lewczuk, M. J.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Gershon, T. J.; Harrison, P. F.; Ilic, J.; Latham, T. E.; Mohanty, G. B.; Puccio, E. M. T.; Band, H. R.; Chen, X.; Dasu, S.; Flood, K. T.; Pan, Y.; Prepost, R.; Vuosalo, C. O.; Wu, S. L.

    2009-10-01

    We have performed a search for the ηb(1S) meson in the radiative decay of the Υ(2S) resonance using a sample of 91.6×106 Υ(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at Eγ=609.3-4.5+4.6(stat)±1.9(syst)MeV, corresponding to an ηb(1S) mass of 9394.2-4.9+4.8(stat)±2.0(syst)MeV/c2. The branching fraction for the decay Υ(2S)→γηb(1S) is determined to be [3.9±1.1(stat)-0.9+1.1(syst)]×10-4. We find the ratio of branching fractions B[Υ(2S)→γηb(1S)]/B[Υ(3S)→γηb(1S)]=0.82±0.24(stat)-0.19+0.20(syst).

  13. Precision Measurement of the Radiative β Decay of the Free Neutron

    NASA Astrophysics Data System (ADS)

    Bales, M. J.; Alarcon, R.; Bass, C. D.; Beise, E. J.; Breuer, H.; Byrne, J.; Chupp, T. E.; Coakley, K. J.; Cooper, R. L.; Dewey, M. S.; Gardner, S.; Gentile, T. R.; He, D.; Mumm, H. P.; Nico, J. S.; O'Neill, B.; Thompson, A. K.; Wietfeldt, F. E.; RDK Collaboration, II

    2016-06-01

    The standard model predicts that, in addition to a proton, an electron, and an antineutrino, a continuous spectrum of photons is emitted in the β decay of the free neutron. We report on the RDK II experiment which measured the photon spectrum using two different detector arrays. An annular array of bismuth germanium oxide scintillators detected photons from 14 to 782 keV. The spectral shape was consistent with theory, and we determined a branching ratio of 0.00335 ±0.00005 [stat ]±0.00015 [syst ] . A second detector array of large area avalanche photodiodes directly detected photons from 0.4 to 14 keV. For this array, the spectral shape was consistent with theory, and the branching ratio was determined to be 0.00582 ±0.00023 [stat ]±0.00062 [syst ] . We report the first precision test of the shape of the photon energy spectrum from neutron radiative decay and a substantially improved determination of the branching ratio over a broad range of photon energies.

  14. Evidence for the eta(b)(1S) meson in radiative Upsilon(2S) decay.

    PubMed

    Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Chaisanguanthum, K S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Godang, R; Kroeger, R; Summers, D J; Zhao, H W; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Del Amo Sanchez, P; Ben-Haim, E; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Miyashita, T S; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; King, G J; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Puccio, E M T; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Prepost, R; Vuosalo, C O; Wu, S L

    2009-10-16

    We have performed a search for the eta_{b}(1S) meson in the radiative decay of the Upsilon(2S) resonance using a sample of 91.6x10(6) Upsilon(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at Egamma=609.3(-4.5)(+4.6)(stat)+/-1.9(syst) MeV, corresponding to an eta(b)(1S) mass of 9394.2(-4.9)(+4.8)(stat)+/-2.0(syst) MeV/c2. The branching fraction for the decay Upsilon(2S)-->gamma(eta)b(1S) is determined to be [3.9+/-1.1(stat)-0.9+1.1(syst)]x10(-4). We find the ratio of branching fractions B[Upsilon(2S)-->gamma(eta)b(1S)]/B[Upsilon(3S)-->gamma(eta)b(1S)]=0.82+/-0.24(stat)(-0.19)(+0.20)(syst). PMID:19905689

  15. Radiative corrections to the Dalitz plot of K{sub l3}{sup {+-}} decays

    SciTech Connect

    Juarez-Leon, C.; Martinez, A.; Neri, M.; Torres, J. J.; Flores-Mendieta, Ruben

    2011-03-01

    We calculate the model-independent radiative corrections to the Dalitz plot of K{sub l3}{sup {+-}} decays to the order of ({alpha}/{pi})(q/M{sub 1}), where q is the momentum transfer and M{sub 1} is the mass of the kaon. The final results are presented, first, with the triple integration over the variables of the bremsstrahlung photon ready to be performed numerically and, second, in an analytical form. These two forms are useful to cross-check on one another and with other calculations. This paper is organized to make it accessible and reliable in the analysis of the Dalitz plot of precision experiments and is not compromised to fixing the form factors at predetermined values. It is assumed that the real photons are kinematically discriminated. Otherwise, our results have a general model-independent applicability.

  16. Observation of hc Radiative Decay hc→γ η' and Evidence for hc→γ η

    NASA Astrophysics Data System (ADS)

    Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; de Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrié, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, S. G.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.; Besiii Collaboration

    2016-06-01

    A search for radiative decays of the P -wave spin singlet charmonium resonance hc is performed based on 4.48 ×108 ψ' events collected with the BESIII detector operating at the BEPCII storage ring. Events of the reaction channels hc→γ η' and γ η are observed with a statistical significance of 8.4 σ and 4.0 σ , respectively, for the first time. The branching fractions of hc→γ η' and hc→γ η are measured to be B (hc→γ η')=(1.52 ±0.27 ±0.29 )×10-3 and B (hc→γ η )=(4.7 ±1.5 ±1.4 )×10-4, respectively, where the first errors are statistical and the second are systematic uncertainties.

  17. Radiative decays of the psi(3097) to two meson final states

    SciTech Connect

    Einsweiler, K.F.

    1984-05-01

    The MARK III detector operating at the SPEAR storage ring has acquired a sample of 2.7 x 10/sup 6/ produced psi(3097)'s. These events are used to investigate the radiative decays of the psi to two meson final states. Such decays are of topical interest because of the unusual QCD laboratory they provide - of particular interest is the possibility of observing glueball states. The process psi ..-->.. ..gamma pi../sup +/..pi../sup -/ is studied. The f(1270) tensor meson is observed and the helicity structure of its production is measured. The data indicate that helicity 2 is suppressed, in disagreement with lowest order QCD calculations. Evidence is presented for the first observation of the theta(1700) in the ..pi../sup +/..pi../sup -/ final state. The strong, but not complete, suppression of this state in the ..pi pi.. channel, combined with the absence of a J/sup P/ = 2/sup +/ signal in a recent MARK III analysis of psi ..-->.. ..gamma.. rho rho, suggest a very mysterious nature for the theta(1700). The process psi ..-->.. ..gamma..K/sup +/K/sup -/ is also studied. The f'(1515) tensor meson is observed with a branching ratio in agreement with the SU(3) symmetry prediction for the standard two gluon radiative decay diagram with no mixing corrections. The helicity structure of the f'(1515) is measured for the first time, and is found to be similar to that of the f(1270). The theta(1700) is observed with high statistics. Its spin and parity are measured, with the result that J/sup P/ = 2/sup +/ is preferred over J/sup P/ = 0/sup +/ at the 99.9% C.L. In addition, evidence is presented for a remarkable narrow state, designated the xi(2220). Its parameters are measured to be: m = 2.218 +- 0.003 +- 0.010 GeV, GAMMA less than or equal to 0.040 GeV at 95% C.L., and BR(psi ..-->.. ..gamma..xi(2220))BR(xi(2220) ..-->.. K/sup +/K/sup -/) = (5.7 +- 1.9 +- 1.4) x 10/sup -5/.

  18. Radiative Decay Engineering 7: Tamm State-Coupled Emission Using a Hybrid Plasmonic-Photonic Structure

    PubMed Central

    Badugu, Ramachandram; Descrovi, Emiliano; Lakowicz, Joseph R.

    2014-01-01

    There is a continuing need to increase the brightness and photostability of fluorophores for use in biotechnology, medical diagnostics and cell imaging. One approach developed during the past decade is to use metallic surfaces and nanostructures. It is now known that excited state fluorophores display interactions with surface plasmons, which can increase the radiative decay rates, modify the spatial distribution of emission and result in directional emission. One important example is Surface Plasmon-Coupled Emission (SPCE). In this phenomenon the fluorophores at close distances from a thin metal film, typically silver, display emission over a small range of angles into the substrate. A disadvantage of SPCE is that the emission occur at large angles relative to the surface normal, and at angles which are larger than the critical angle for the glass substrate. The large angles make it difficult to collect all the coupled emission and have prevented use of SPCE with high-throughput and/or array applications. In the present report we describe a simple multi-layer metal-dielectric structure which allows excitation with light that is perpendicular (normal) to the plane and provides emission within a narrow angular distribution that is normal to the plane. This structure consist of a thin silver film on top of a multi-layer dielectric Bragg grating, with no nanoscale features except for the metal or dielectric layer thicknesses. Our structure is designed to support optical Tamm states, which are trapped electromagnetic modes between the metal film and the underlying Bragg grating. We used simulations with the transfer matrix method to understand the optical properties of Tamm states and localization of the modes or electric fields in the structure. Tamm states can exist with zero in-plane wavevector components and can be created without the use of a coupling prism. We show that fluorophores on top of the metal film can interact with the Tamm state under the metal film

  19. Radiative decay of self-trapped excitons in CaMoO4 and MgMoO4 crystals

    NASA Astrophysics Data System (ADS)

    Mikhailik, V. B.; Kraus, H.; Itoh, M.; Iri, D.; Uchida, M.

    2005-11-01

    Spectroscopic properties of CaMoO4 and MgMoO4 crystals were studied in view of their application to cryogenic scintillation detectors. Luminescence spectra and the luminescence decay kinetics were measured over a wide range of temperatures (8-300 K). For the first time we measured time-resolved luminescence spectra of CaMoO4. In addition to the green emission arising from the triplet state of self-trapped excitons (STEs), a new band at around 430 nm with a decay time constant 10 ± 3 ns was observed at T = 8 K. This emission is assigned to the radiative decay of a singlet STE. The relaxation of electronic excitations in the crystals under study is discussed on the basis of our current understanding of their electronic structures and a configuration coordinate model for the radiative decay of STEs. The model includes adiabatic potential energy surfaces (APESs) associated with singlet and triplet states and explains the variation of the luminescence kinetics with temperature as a result of a re-distribution in the population of these states. Thus, judging from the change of the singlet STE emission due to temperature variation, we infer the existence of an energy barrier between the singlet and triplet APESs. The multi-exponential character of the decay of the triplet emission can be understood assuming that the relevant radiative transitions originate from different minima of the triplet APES. Non-radiative energy transfer processes control the population of these states, resulting in thermal variation of the intensities of the different emission components.

  20. Temperature and magnetic-field dependence of radiative decay in colloidal germanium quantum dots.

    PubMed

    Robel, István; Shabaev, Andrew; Lee, Doh C; Schaller, Richard D; Pietryga, Jeffrey M; Crooker, Scott A; L Efros, Alexander; Klimov, Victor I

    2015-04-01

    We conduct spectroscopic and theoretical studies of photoluminescence (PL) from Ge quantum dots (QDs) fabricated via colloidal synthesis. The dynamics of late-time PL exhibit a pronounced dependence on temperature and applied magnetic field, which can be explained by radiative decay involving two closely spaced, slowly emitting exciton states. In 3.5 nm QDs, these states are separated by ∼1 meV and are characterized by ∼82 μs and ∼18 μs lifetimes. By using a four-band formalism, we calculate the fine structure of the indirect band-edge exciton arising from the electron-hole exchange interaction and the Coulomb interaction of the Γ-point hole with the anisotropic charge density of the L-point electron. The calculations suggest that the observed PL dynamics can be explained by phonon-assisted recombination of excitons thermally distributed between the lower-energy "dark" state with the momentum projection J = ± 2 and a higher energy "bright" state with J = ± 1. A fairly small difference between lifetimes of these states is due to their mixing induced by the exchange term unique to crystals with a highly symmetric cubic lattice such as Ge.

  1. Branching Fractions and CP-Violating Asymmetries in Radiative B Decays to eta K gamma

    SciTech Connect

    Aubert, B.

    2008-05-14

    The authors present measurements of the CP-violation parameters S and C for the radiative decay B{sup 0} {yields} {eta}K{sub S}{sup 0}{gamma}; for B {yields} {eta}K{gamma} they also measure the branching fractions and for B{sup +} {yields} {eta}K{sup +}{gamma} the time-integrated charge asymmetry {Alpha}{sub ch}. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation. The results are S = -0.18{sub -0.46}{sup +0.49} {+-} 0.12, C = -0.32{sub -0.39}{sup +0.40} {+-} 0.07, {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = (7.1{sub -2.0}{sup +2.1} {+-} 0.4) x 10{sup -6}, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = (7.7 {+-} 1.0 {+-} 0.4) x 10{sup -6}, and {Alpha}{sub ch} = (-9.0{sub -9.8}{sup +10.4} {+-} 1.4) x 10{sup -2}. The first error quoted is statistical and the second systematic.

  2. Relativistic electron acceleration and decay time scales in the inner and outer radiation belts: SAMPEX

    NASA Technical Reports Server (NTRS)

    Baker, D. N.; Blake, J. B.; Callis, L. B.; Cummings, J. R.; Hovestadt, D.; Kanekal, S.; Klecker, B.; Mewaldt, R. A.; Zwickl, R. D.

    1994-01-01

    High-energy electrons have been measured systematically in a low-altitude (520 x 675 km), nearly polar (inclination = 82 deg) orbit by sensitive instruments onboard the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX). Count rate channels with electron energy thresholds ranging from 0.4 MeV to 3.5 MeV in three different instruments have been used to examine relativistic electron variations as a function of L-shell parameter and time. A long run of essentially continuous data (July 1992 - July 1993) shows substantial acceleration of energetic electrons throughout much of the magnetosphere on rapid time scales. This acceleration appears to be due to solar wind velocity enhancements and is surprisingly large in that the radiation belt 'slot' region often is filled temporarily and electron fluxes are strongly enhanced even at very low L-values (L aprroximately 2). A superposed epoch analysis shows that electron fluxes rise rapidly for 2.5 is approximately less than L is approximately less than 5. These increases occur on a time scale of order 1-2 days and are most abrupt for L-values near 3. The temporal decay rate of the fluxes is dependent on energy and L-value and may be described by J = Ke-t/to with t(sub o) approximately equals 5-10 days. Thus, these results suggest that the Earth's magnetosphere is a cosmic electron accelerator of substantial strength and efficiency.

  3. Lepton flavor violating decay of SM-like Higgs boson in a radiative neutrino mass model

    NASA Astrophysics Data System (ADS)

    Thuc, T. T.; Hue, L. T.; Long, H. N.; Nguyen, T. Phong

    2016-06-01

    The lepton flavor violating decay of the Standard Model-like Higgs boson (LFVHD) is discussed in the framework of the radiative neutrino mass model built in [K. Nishiwaki, H. Okada, and Y. Orikasa, Phys. Rev. D 92, 093013 (2015)]. The branching ratio (BR) of the LFVHD is shown to reach 10-5 in the most interesting region of the parameter space shown in [K. Nishiwaki, H. Okada, and Y. Orikasa, Phys. Rev. D 92, 093013 (2015)]. The dominant contributions come from the singly charged Higgs mediations, namely, the coupling of h2± with exotic neutrinos. Furthermore, if the doubly charged Higgs boson is heavy enough to allow the mass of h2± around 1 TeV, the mentioned BR can reach 10-4 . In addition, we obtain that the large values of Br (h →μ τ ) lead to very small ones of Br (h →e τ ) , much smaller than the various sensitivities of current experiments.

  4. Experimental search for radiative decays of the pentaquark baryon Θ+(1540)

    NASA Astrophysics Data System (ADS)

    Barmin, V. V.; Asratyan, A. E.; Borisov, V. S.; Curceanu, C.; Davidenko, G. V.; Dolgolenko, A. G.; Guaraldo, C.; Kubantsev, M. A.; Larin, I. F.; Matveev, V. A.; Shebanov, V. A.; Shishov, N. N.; Sokolov, L. I.; Tumanov, G. K.; Verebryusov, V. S.

    2010-07-01

    The data on the reactions K +Xe → K 0 γX and K +Xe → K + γX, obtained with the bubble chamber DIANA, have been analyzed for possible radiative decays of the Θ+(1540) baryon: Θ+ → K 0 pγ and Θ+ → K + nγ. No signals have been observed, and we derive the upper limits Γ(Θ+ → K 0 pγ)/Γ(Θ+ → K 0 p) < 0.032 and Γ(Θ+ → K + nγ)/Γ(Θ+ → K + nγ) < 0.041 which, using our previous measurement of Γ(Θ+ → KN) = 0.39 ± 0.10 MeV, translate to Γ(Θ+ → K 0 pγ) < 8 keV and Γ(Θ+ → K + nγ) < 11 keV at 90% confidence level. We have also measured the cross sections of K +-induced reactions involving emission of a neutral pion: σ( K + n → K 0 pπ 0) = 68 ± 18 µb and σ( K + N → K + Nπ 0) = 30 ± 8 µb for incident K + momentum of 640 MeV.

  5. Branching fractions and CP-violating asymmetries in radiative B decays to ηKγ

    NASA Astrophysics Data System (ADS)

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Tico, J. Garra; Grauges, E.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G. S.; Battaglia, M.; Brown, D. N.; Cahn, R. N.; Jacobsen, R. G.; Kerth, L. T.; Kolomensky, Yu. G.; Kukartsev, G.; Lynch, G.; Osipenkov, I. L.; Ronan, M. T.; Tackmann, K.; Tanabe, T.; Hawkes, C. M.; Soni, N.; Watson, A. T.; Koch, H.; Schroeder, T.; Walker, D.; Asgeirsson, D. J.; Cuhadar-Donszelmann, T.; Fulsom, B. G.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Barrett, M.; Khan, A.; Teodorescu, L.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Abachi, S.; Buchanan, C.; Gary, J. W.; Liu, F.; Long, O.; Shen, B. C.; Vitug, G. M.; Yasin, Z.; Zhang, L.; Sharma, V.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Mazur, M. A.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Flacco, C. J.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Schalk, T.; Schumm, B. A.; Seiden, A.; Wang, L.; Wilson, M. G.; Winstrom, L. O.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Fang, F.; Hitlin, D. G.; Narsky, I.; Piatenko, T.; Porter, F. C.; Andreassen, R.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Blanc, F.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Hirschauer, J. F.; Kreisel, A.; Nagel, M.; Nauenberg, U.; Olivas, A.; Smith, J. G.; Ulmer, K. A.; Wagner, S. R.; Ayad, R.; Soffer, A.; Toki, W. H.; Wilson, R. J.; Altenburg, D. D.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Kobel, M. J.; Mader, W. F.; Nogowski, R.; Schubert, K. R.; Schwierz, R.; Sundermann, J. E.; Volk, A.; Bernard, D.; Bonneaud, G. R.; Latour, E.; Thiebaux, Ch.; Verderi, M.; Clark, P. J.; Gradl, W.; Playfer, S.; Watson, J. E.; Chaisanguanthum, K. S.; Morii, M.; Dubitzky, R. S.; Marks, J.; Schenk, S.; Uwer, U.; Klose, V.; Lacker, H. M.; Lopez, L.; Palano, A.; Pappagallo, M.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Franchini, P.; Luppi, E.; Negrini, M.; Petrella, A.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Buzzo, A.; Contri, R.; Lo Vetere, M.; Macri, M. M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Santroni, A.; Tosi, S.; Lazzaro, A.; Lombardo, V.; Palombo, F.; de Nardo, G.; Lista, L.; Monorchio, D.; Onorato, G.; Sciacca, C.; Castelli, G.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Voci, C.; Biasini, M.; Covarelli, R.; Manoni, E.; Angelini, C.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Marchiori, G.; Morganti, M.; Neri, N.; Paoloni, E.; Rizzo, G.; Walsh, J. J.; Anulli, F.; Baracchini, E.; Cavoto, G.; Del Re, D.; di Marco, E.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Jackson, P. D.; Gioi, L. Li; Mazzoni, M. A.; Morganti, S.; Piredda, G.; Polci, F.; Renga, F.; Voena, C.; Bianchi, F.; Gamba, D.; Pelliccioni, M.; Bomben, M.; Bosisio, L.; Cartaro, C.; Della Ricca, G.; Lanceri, L.; Vitale, L.; Bard, D. J.; Dauncey, P. D.; Nash, J. A.; Vazquez, W. Panduro; Tibbetts, M.; Behera, P. K.; Chai, X.; Charles, M. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Dong, L.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Lae, C. K.; Denig, A. G.; Fritsch, M.; Schott, G.; Arnaud, N.; Béquilleux, J.; D'Orazio, A.; Davier, M.; da Costa, J. Firmino; Grosdidier, G.; Höcker, A.; Lepeltier, V.; Le Diberder, F.; Lutz, A. M.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Chukwudi, C. K.; George, K. A.; di Lodovico, F.; Sacco, R.; Sigamani, M.; Cowan, G.; Flaecher, H. U.; Hopkins, D. A.; Paramesvaran, S.; Salvatore, F.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Alwyn, K. E.; Barlow, N. R.; Barlow, R. J.; Chia, Y. M.; Edgar, C. L.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Dallapiccola, C.; Hertzbach, S. S.; Li, X.; Salvati, E.; Saremi, S.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Koeneke, K.; Sciolla, G.; Spitznagel, M.; Taylor, F.; Yamamoto, R. K.; Zhao, M.; McLachlin, S. E.; Patel, P. M.; Robertson, S. H.; Bauer, J. M.; Cremaldi, L.; Eschenburg, V.; Godang, R.; Kroeger, R.; Sanders, D. A.; Summers, D. J.; Zhao, H. W.; Brunet, S.; Côté, D.; Simard, M.; Taras, P.; Viaud, F. B.; Nicholson, H.; Baak, M. A.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Benelli, G.; Corwin, L. A.; Honscheid, K.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Regensburger, J. J.; Sekula, S. J.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Kolb, J. A.; Lu, M.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Del Amo Sanchez, P.; Ben-Haim, E.; Briand, H.; Calderini, G.; Chauveau, J.; David, P.; Del Buono, L.; Hamon, O.; Leruste, Ph.; Ocariz, J.; Perez, A.; Prendki, J.; Gladney, L.; Biesiada, J.; Pegna, D. Lopes; Lu, C.; Olsen, J.; Smith, A. J. S.; Telnov, A. V.; Ebert, M.; Hartmann, T.; Schröder, H.; Waldi, R.; Adye, T.; Franek, B.; Olaiya, E. O.; Roethel, W.; Wilson, F. F.; Emery, S.; Escalier, M.; Esteve, L.; Gaidot, A.; Ganzhur, S. F.; de Monchenault, G. Hamel; Kozanecki, W.; Vasseur, G.; Yèche, Ch.; Zito, M.; Chen, X. R.; Liu, H.; Park, W.; Purohit, M. V.; White, R. M.; Wilson, J. R.; Allen, M. T.; Aston, D.; Bartoldus, R.; Bechtle, P.; Benitez, J. F.; Cenci, R.; Coleman, J. P.; Convery, M. R.; Dingfelder, J. C.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Field, R. C.; Gabareen, A. M.; Gowdy, S. J.; Graham, M. T.; Grenier, P.; Hast, C.; Innes, W. R.; Kaminski, J.; Kelsey, M. H.; Kim, H.; Kim, P.; Kocian, M. L.; Leith, D. W. G. S.; Li, S.; Lindquist, B.; Luitz, S.; Luth, V.; Lynch, H. L.; Macfarlane, D. B.; Marsiske, H.; Messner, R.; Muller, D. R.; Neal, H.; Nelson, S.; O'Grady, C. P.; Ofte, I.; Perazzo, A.; Perl, M.; Ratcliff, B. N.; Roodman, A.; Salnikov, A. A.; Schindler, R. H.; Schwiening, J.; Snyder, A.; Su, D.; Sullivan, M. K.; Suzuki, K.; Swain, S. K.; Thompson, J. M.; Va'Vra, J.; Wagner, A. P.; Weaver, M.; West, C. A.; Wisniewski, W. J.; Wittgen, M.; Wright, D. H.; Wulsin, H. W.; Yarritu, A. K.; Yi, K.; Young, C. C.; Ziegler, V.; Burchat, P. R.; Edwards, A. J.; Majewski, S. A.; Miyashita, T. S.; Petersen, B. A.; Wilden, L.; Ahmed, S.; Alam, M. S.; Bula, R.; Ernst, J. A.; Pan, B.; Saeed, M. A.; Zain, S. B.; Spanier, S. M.; Wogsland, B. J.; Eckmann, R.; Ritchie, J. L.; Ruland, A. M.; Schilling, C. J.; Schwitters, R. F.; Drummond, B. W.; Izen, J. M.; Lou, X. C.; Ye, S.; Azzolini, V.; Lopez-March, N.; Martinez-Vidal, F.; Milanes, D. A.; Oyanguren, A.; Albert, J.; Banerjee, Sw.; Bhuyan, B.; Choi, H. H. F.; Hamano, K.; Kowalewski, R.; Lewczuk, M. J.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Gershon, T. J.; Harrison, P. F.; Ilic, J.; Latham, T. E.; Mohanty, G. B.; Band, H. R.; Chen, X.; Dasu, S.; Flood, K. T.; Pan, Y.; Pierini, M.; Prepost, R.; Vuosalo, C. O.; Wu, S. L.

    2009-01-01

    We present measurements of the CP-violation parameters S and C for the radiative decay B0→ηKS0γ; for B→ηKγ we also measure the branching fractions and for B+→ηK+γ the time-integrated charge asymmetry Ach. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465×106 B Bmacr pairs produced in e+e- annihilation. The results are S=-0.18-0.46+0.49±0.12, C=-0.32-0.39+0.40±0.07, B(B0→ηK0γ)=(7.1-2.0+2.1±0.4)×10-6, B(B+→ηK+γ)=(7.7±1.0±0.4)×10-6, and Ach=(-9.0-9.8+10.4±1.4)×10-2. The first error quoted is statistical and the second systematic.

  6. Asymmetries in rare radiative leptonic and semileptonic decays of B mesons

    SciTech Connect

    Balakireva, I. A. Nikitin, N. V. Tlisov, D. A.

    2010-10-15

    The time-dependent and time-independent CP asymmetries A({sub CP})/{sup B}{sub q}{sup 0{yields}f} ({tau}) and A({sub CP})/{sup B}{sub q}{sup 0{yields}f}) (s-circumflex) for rare semileptonic and radiative leptonic decays of B mesons are calculated by the method of helicity amplitudes. The sensitivity of CP asymmetries to various extensions of the Standard Model that have an operator basis that is identical to the operator basis of the Standard Model is investigated. It is shown that, by combining information about the form of the charge lepton asymmetry A{sub FB} at small values of the square of the invariant dilepton mass and information about the average value of the time-dependent CP asymmetry, one can in principle determine the relative phases of the Wilson coefficients C7{sub {gamma}}, C-{sub 9}V, and C10A in the effective Hamiltonian for b {sup {yields} {l_brace}}d, s{r_brace}l{sup +}l{sup -} transitions.

  7. Flavor Changing Neutral Coupling Mediated Radiative Top Quark Decays at Next-to-Leading Order in QCD

    SciTech Connect

    Drobnak, Jure; Kamenik, Jernej F.; Fajfer, Svjetlana

    2010-06-25

    We compute the branching ratios for the rare top quark decays t{yields}c{gamma} and t{yields}cZ mediated by effective flavor changing neutral couplings at next-to-leading order in QCD, including the effects due to operator mixing. After resumming contributions of the order of [{alpha}{sub s}log({Lambda}/m{sub t})]{sup n}, where {Lambda} is the scale at which the effective operators are generated, using renormalization group methods, we compute finite matrix element corrections and study the effects of experimental kinematic cuts on the extracted branching ratios. We find that the t{yields}c{gamma} decay can also be used to probe the effective operators mediating t{yields}cg processes, since the latter can naturally contribute 10% or more to the radiative decay. Conversely, any experimental signal of t{yields}cg would indicate a natural lower bound on t{yields}cZ, {gamma}.

  8. Determination of the b-quark Mass and Nonperturbative parameters in Semileptonic and Radiative Penguin Decays at BaBar

    SciTech Connect

    Tackmann, Kerstin; collaboration, for the BABAR

    2008-01-23

    Knowing the mass of the b-quark is essential to the study of the structure and decays of B mesons as well as to future tests of the Higgs mechanism of mass generation. We present recent preliminary measurements of the b-quark mass and related nonperturbative parameters from moments of kinematic distributions in charmed and charmless semileptonic and radiative penguin B decays. Their determination from charmless semileptonic B decays is the first measurement in this mode. The data were collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -}-collider at the Stanford Linear Accelerator Center at a center-of-momentum energy of 10:58 GeV.

  9. Search for Di-Muon Decays of a Light Scalar Higgs Boson in Radiative Upsilon(1S) Decays

    SciTech Connect

    Prasad, Vindhyawasini

    2013-08-01

    We search for di-muon decays of a low-mass Higgs boson (A0) in the fully reconstructed decay chain of Υ(2S, 3S ) → π+π-Υ(1S ), Υ(1S ) → γA0, A0 → μ+μ+. The A0 is predicted by several extensions of the Standard Model (SM), including the Next-to-Minimal Supersymmetric Standard Model (NMSSM). NMSSM introduces a CP-odd light Higgs boson whose mass could be less than 10 GeV/c2. The data samples used in this analysis contain 92.8 × 106 Υ(2S ) and 116.8 × 106 Υ(3S ) events collected by the BABAR detector. The Υ(1S ) sample is selected by tagging the pion pair in the Υ(2S, 3S ) → π+π-Υ(1S ) transitions. We find no evidence for A0 production and set 90% confidence level (C.L.) upper limits on the product branching fraction B(Υ(1S ) → γA0) × B(A0 → μ+μ-) in the range of (0.28 - 9.7) × 10-6 for 0.212 ≤ mA0 ≤ 9.20 GeV/c2. We also combine our results with previous BABAR results of Υ(2S, 3S ) → γA0, A0 → μ+μ- to set limits on the effective coupling ( fΥ) of the b-quark to the A0, f 2 Υ × B(A0 → μ+μ-), at the level of (0.29- 40) × 10-6 for 0.212 ≤ mA0 ≤ 9.2 GeV/c2.

  10. Radioactive decay.

    PubMed

    Groch, M W

    1998-01-01

    When a parent radionuclide decays to its daughter radionuclide by means of alpha, beta, or isomeric transition, the decay follows an exponential form, which is characterized by the decay constant lambda. The decay constant represents the probability per unit time that a single radioatom will decay. The decay equation can be used to provide a useful expression for radionuclide decay, the half-life, the time when 50% of the radioatoms present will have decayed. Radiotracer half-life has direct implications in nuclear imaging, radiation therapy, and radiation safety because radionuclide half-life affects the ability to evaluate tracer kinetics and create appropriate nuclear images and also affects organ, tumor, and whole-body radiation dose. The number of radioatoms present in a sample is equal to the activity, defined as the number of transitions per unit time, divided by the decay constant; the mass of radioatoms present in a sample can be calculated to determine the specific activity (activity per unit mass). The dynamic relationship between the number of parent and daughter atoms present over time may lead to radioactive equilibrium, which takes two forms--secular and transient--and has direct relevance to generator-produced radionuclides.

  11. Temperature-dependent radiative decay of localized excitons in a type-II GaAs/AlAs superlattice

    SciTech Connect

    Angell, J.F.; Sturge, M.D. )

    1993-08-15

    The low-temperature luminescence intensity decay following pulse excitation of localized excitons in a type-II GaAs/AlAs superlattice is nonexponential. The decay obeys a previously derived theory in which excitons experience a distribution of decay rates corresponding to a Gaussian distribution of [ital X] to [Gamma] scattering matrix elements. At high temperature the decay is exponential with a rate equal to the mean of the distribution. The transition is attributed to excitons motionally averaging the distribution as temperature is increased and thermal delocalization occurs. This paper develops a theory of radiative decay which takes into account motional averaging and is valid at all temperatures. The theory has one fitting parameter [gamma] which is the ratio of exciton lifetime to jump time and determines the extent of averaging performed. Good agreement is found between the theory and experimental data; however, at high excitation intensity and low exciton energy the theory must be modified to take saturation of localized states into account. The temperature dependence of the fitting parameter [gamma] reveals two delocalization processes, the activation energies of which are interpreted as the localization energy and the exciton binding energy.

  12. Testing the Standard Model with Radiative Penguin Decays at BaBar

    SciTech Connect

    Tuggle, J; /Maryland U.

    2008-04-22

    The author discusses two recent results in b {yields} s{gamma} decays from BABAR. The first is a measurement of the branching fraction and photon energy spectrum in the B meson frame of the decay B {yields} X{sub s{gamma}}. The second result probes the photon polarization via time-dependent CP violation in neutral B decays to K*{sup 0}{gamma}.

  13. New decay branches of the radiative capture reaction {sup 12}C({sup 16}O,{gamma}){sup 28}Si

    SciTech Connect

    Lebhertz, D.; Courtin, S.; Haas, F.; Salsac, M.-D.; Beck, C.; Michalon, A.; Rousseau, M.; Marley, P. L.; Glover, R. G.; Kent, P. E.; Hutcheon, D. A.; Davis, C.; Pearson, J. E.

    2009-01-28

    Resonances in the {sup 12}C({sup 16}O,{gamma}){sup 28}Si radiative capture process at energies around the Coulomb barrier have been probed using the very selective 0 deg. Dragon spectrometer at Triumf and its associated BGO {gamma}-array. For the first time the full level scheme involved in this process has been measured and shows previously unobserved {gamma}-decay to doorway states around 11 MeV in {sup 28}Si.

  14. Experimental search for radiative decays of the pentaquark baryon {Theta}{sup +}(1540)

    SciTech Connect

    Barmin, V. V.; Asratyan, A. E.; Borisov, V. S.; Curceanu, C.; Davidenko, G. V.; Dolgolenko, A. G.; Guaraldo, C.; Kubantsev, M. A.; Larin, I. F.; Matveev, V. A.; Shebanov, V. A.; Shishov, N. N.; Sokolov, L. I.; Tumanov, G. K.; Verebryusov, V. S.

    2010-07-15

    The data on the reactions K{sup +}Xe {sup {yields}}K{sup 0{gamma}}X and K{sup +}Xe {sup {yields}}K{sup +{gamma}}X, obtained with the bubble chamber DIANA, have been analyzed for possible radiative decays of the {Theta}{sup +}(1540) baryon: {Theta}{sup +} {sup {yields}}K{sup 0}p{gamma} and {Theta}{sup +} {sup {yields}}K{sup +}n{gamma}. No signals have been observed, and we derive the upper limits {Gamma}({Theta}{sup +} {sup {yields}}K{sup 0}p{gamma})/{Gamma}({Theta}{sup +} {sup {yields}}K{sup 0}p) < 0.032 and {Gamma}({Theta}{sup +} {sup {yields}}K{sup +}n{gamma})/{Gamma}({Theta}{sup +} {sup {yields}}K{sup +}n{gamma}) < 0.041 which, using our previous measurement of {Gamma}({Theta}{sup +} {sup {yields}}KN) = 0.39 {+-} 0.10 MeV, translate to {Gamma}({Theta}{sup +} {sup {yields}}K{sup 0}p{gamma}) < 8 keV and {Gamma}({Theta}{sup +} {sup {yields}}K{sup +}n{gamma}) < 11 keV at 90% confidence level. We have also measured the cross sections of K{sup +}-induced reactions involving emission of a neutral pion: {sigma}(K{sup +}n {sup {yields}}K{sup 0}p{pi}{sup 0}) = 68 {+-} 18 {mu}b and {sigma}(K{sup +}N {sup {yields}}K{sup +}N{pi}{sup 0}) = 30 {+-} 8 {mu}b for incident K{sup +} momentum of 640 MeV.

  15. Search for charmonium and charmoniumlike states in {Upsilon}(2S) radiative decays

    SciTech Connect

    Wang, X. L.; Yuan, C. Z.; Wang, P.; Shen, C. P.; Hayasaka, K.; Iijima, T.; Miyazaki, Y.; Ohshima, T.; Senyo, K.; Seon, O.; Adachi, I.; Haba, J.; Itoh, R.; Iwasaki, Y.; Katayama, N.; Kichimi, H.; Nakao, M.; Nishida, S.; Sakai, Y.; Trabelsi, K.

    2011-10-01

    Using a sample of 158x10{sup 6} {Upsilon}(2S) events collected with the Belle detector, charmonium and charmoniumlike states with even charge parity are searched for in {Upsilon}(2S) radiative decays. No significant {chi}{sub cJ} or {eta}{sub c} signal is observed, and the following upper limits at 90% confidence level (C. L.) are obtained: B({Upsilon}(2S){yields}{gamma}{chi}{sub c0})<1.0x10{sup -4}, B({Upsilon}(2S){yields}{gamma}{chi}{sub c1})<3.6x10{sup -6}, B({Upsilon}(2S){yields}{gamma}{chi}{sub c2})<1.5x10{sup -5}, and B({Upsilon}(2S){yields}{gamma}{eta}{sub c})<2.7x10{sup -5}. No significant signal of any charmoniumlike state is observed, and we obtain the limits B({Upsilon}(2S){yields}{gamma}X(3872))xB(X(3872){yields}{pi}{sup +}{pi}{sup -}J/{psi})<0.8x10{sup -6}, B({Upsilon}(2S){yields}{gamma}X(3872))x B(X(3872){yields}{pi}{sup +}{pi}{sup -}{pi}{sup 0}J/{psi})<2.4x10{sup -6}, B({Upsilon}(2S){yields}{gamma}X(3915))xB(X(3915){yields}{omega}J/{psi})<2.8x10{sup -6}, B({Upsilon}(2S){yields}{gamma}Y(4140))xB(Y(4140){yields}{phi}J/{psi}))<1.2x10{sup -6}, and B({Upsilon}(2S){yields}{gamma}X(4350))xB(X(4350){yields}{phi}J/{psi}))<1.3x10{sup -6} at 90% C. L.

  16. Radiative Penguin Decays of B Mesons: Measurements of B to K* gamma, B to K2* gamma, and Search for B0 to phi gamma

    SciTech Connect

    Bauer, J.

    2005-01-03

    Electromagnetic radiative penguin decays of the B meson were studied with the BaBar detector at SLAC's PEP-II asymmetric-energy B Factory. Branching fractions and isospin asymmetry of the decay B {yields} K*{gamma}, branching fractions of B {yields} K*{sub 2}(1430){gamma}, and a search for B{sup 0} {yields} {phi}{gamma} are presented. The decay rates may be enhanced by contributions from non-standard model processes.

  17. Morphology of the nonspherically decaying radiation beam generated by a rotating superluminal source: comment.

    PubMed

    Hannay, J H

    2008-09-01

    The same elementary disproof of the claimed "nonspherical" decay that I have given before applies. A comment asserting the correctness of the relevant formula from a standard text on electrodynamics is added at the end. PMID:18758540

  18. Rare And Radiative B Meson Decays From the BaBar Experiment

    SciTech Connect

    Stelzer, J.; /SLAC

    2006-08-28

    Since its start in 1999 the BABAR experiment has collected a vast amount of data. Electron-positron collisions at the energy of the {Upsilon}(4S) resonance have produced about 240 million coherent B{sup 0}{bar B}{sup 0} and B{sup +}B{sup -} pairs, opening the doors for exploration of rare B meson decays. An overview of the electroweak penguin physics program of BABAR is given, the analysis of two specific decays is presented in detail.

  19. Radiative Corrections for Wto e barν Decay in the Weinberg-Salam Model

    NASA Astrophysics Data System (ADS)

    Inoue, K.; Kakuto, A.; Komatsu, H.; Takeshita, S.

    1980-09-01

    The one-loop corrections for the Wto e barν decay rate are calculated in the Weinberg-Salam model with arbitrary number of generations. The on-shell renormalization prescription and the 't Hooft-Feynman gauge are employed. Divergences are treated by the dimensional regularization method. Some numerical estimates for the decay rate are given in the three-generation model. It is found that there are significant corrections mainly owing to fermion-mass singularities.

  20. Search for dimuon decays of a light scalar boson in radiative transitions Upsilon-->gammaA0.

    PubMed

    Aubert, B; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Martinelli, M; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Petigura, E; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Ongmongkolku, P; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Wilson, R J; Feltresi, E; Hauke, A; Jasper, H; Karbach, T M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Volk, A; Bernard, D; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Fioravanti, E; Franchini, P; Luppi, E; Munerato, M; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Guido, E; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Chaisanguanthum, K S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Tibbetts, M; Behera, P K; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Derkach, D; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Malaescu, B; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Hafner, A; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Schram, M; Biassoni, P; Lazzaro, A; Lombardo, V; Palombo, F; Stracka, S; Bauer, J M; Cremaldi, L; Godang, R; Kroeger, R; Sonnek, P; Summers, D J; Zhao, H W; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; del Amo Sanchez, P; Ben-Haim, E; Bonneaud, G R; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Marchiori, G; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Allen, M T; Aston, D; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Franco Sevilla, M; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Young, C C; Ziegler, V; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Burchat, P R; Edwards, A J; Miyashita, T S; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Soffer, A; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Wray, B C; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; King, G J; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Puccio, E M T; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Prepost, R; Vuosalo, C O; Wu, S L

    2009-08-21

    We search for evidence of a light scalar boson in the radiative decays of the Upsilon(2S) and Upsilon(3S) resonances: Upsilon(2S,3S)-->gammaA0, A0-->mu+mu-. Such a particle 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 the mass range 0.212 < or = mA0 < or = 9.3 GeV in the samples of 99 x 10(6) Upsilon(2S) and 122 x 10(6) Upsilon(3S) decays collected by the BABAR detector at the SLAC PEP-II B factory and set stringent upper limits on the effective coupling of the b quark to the A0. We also limit the dimuon branching fraction of the etab meson: B(etab-->mu+mu-)<0.9% at 90% confidence level.

  1. Search for (η_b) and (η_b^') in Inclusive Radiative Decays of the (Υ^') and (Υ^'').

    NASA Astrophysics Data System (ADS)

    Muramatsu, Hajime

    2003-04-01

    We have searched for possible production of the ground state of the b(barb) system, ( η b ) and its excited state, ( η_b^' ) in radiative decays of ( Υ^'' ) and ( Υ^' ) through the hindered magnetic dipole (M1) transitions (( Υ^'' arrow ) ((η _b) or ( η _b^')) + (γ )) and (( Υ^' arrow η _b+ γ )). Using the CLEO III detector, we have collected ( ˜ 1fb-1 ) of data on each of the ( Υ^'' ) and ( Υ^' ) resonances, corresponding to ( ˜4(6)×10^6) ( Υ^''(Υ^') ) decays. No significant evidence for such transitions were found. We set upper limits on B(( Υ^'' arrow ) (η _b) + ( γ )), B(( Υ^'' arrow ) ( η _b^') + ( γ )), and B(( Υ^' arrow ) (η _b) + ( γ )) which rule out many previously published phenomenological estimates of these branching fractions.

  2. Search for Dimuon Decays of a Light Scalar Boson in Radiative Transitions Υ→γA0

    NASA Astrophysics Data System (ADS)

    Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lynch, G.; Osipenkov, I. L.; Petigura, E.; Tackmann, K.; Tanabe, T.; Hawkes, C. M.; Soni, N.; Watson, A. T.; Koch, H.; Schroeder, T.; Asgeirsson, D. J.; Fulsom, B. G.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Barrett, M.; Khan, A.; Randle-Conde, A.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Atmacan, H.; Gary, J. W.; Liu, F.; Long, O.; Vitug, G. M.; Yasin, Z.; Sharma, V.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Mazur, M. A.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Schalk, T.; Schumm, B. A.; Seiden, A.; Wang, L.; Winstrom, L. O.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Fang, F.; Hitlin, D. G.; Narsky, I.; Ongmongkolku, P.; Piatenko, T.; Porter, F. C.; Andreassen, R.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Hirschauer, J. F.; Nagel, M.; Nauenberg, U.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Toki, W. H.; Wilson, R. J.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, T. M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Kobel, M. J.; Nogowski, R.; Schubert, K. R.; Schwierz, R.; Volk, A.; Bernard, D.; Latour, E.; Verderi, M.; Clark, P. J.; Playfer, S.; Watson, J. E.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Fioravanti, E.; Franchini, P.; Luppi, E.; Munerato, M.; Negrini, M.; Petrella, A.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Contri, R.; Guido, E.; Lo Vetere, M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Tosi, S.; Chaisanguanthum, K. S.; Morii, M.; Adametz, A.; Marks, J.; Schenk, S.; Uwer, U.; Bernlochner, F. U.; Klose, V.; Lacker, H. M.; Bard, D. J.; Dauncey, P. D.; Tibbetts, M.; Behera, P. K.; Charles, M. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Dong, L.; Eyges, V.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Arnaud, N.; Béquilleux, J.; D'Orazio, A.; Davier, M.; Derkach, D.; Firmino da Costa, J.; Grosdidier, G.; Le Diberder, F.; Lepeltier, V.; Lutz, A. M.; Malaescu, B.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Clarke, C. K.; di Lodovico, F.; Sacco, R.; Sigamani, M.; Cowan, G.; Paramesvaran, S.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Hafner, A.; Alwyn, K. E.; Bailey, D.; Barlow, R. J.; Jackson, G.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Dallapiccola, C.; Salvati, E.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Henderson, S. W.; Sciolla, G.; Spitznagel, M.; Yamamoto, R. K.; Zhao, M.; Patel, P. M.; Robertson, S. H.; Schram, M.; Biassoni, P.; Lazzaro, A.; Lombardo, V.; Palombo, F.; Stracka, S.; Bauer, J. M.; Cremaldi, L.; Godang, R.; Kroeger, R.; Sonnek, P.; Summers, D. J.; Zhao, H. W.; Simard, M.; Taras, P.; Nicholson, H.; de Nardo, G.; Lista, L.; Monorchio, D.; Onorato, G.; Sciacca, C.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Corwin, L. A.; Honscheid, K.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Regensburger, J. J.; Sekula, S. J.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Kolb, J. A.; Lu, M.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Castelli, G.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Voci, C.; Del Amo Sanchez, P.; Ben-Haim, E.; Bonneaud, G. R.; Briand, H.; Chauveau, J.; Hamon, O.; Leruste, Ph.; Marchiori, G.; Ocariz, J.; Perez, A.; Prendki, J.; Sitt, S.; Gladney, L.; Biasini, M.; Manoni, E.; Angelini, C.; Batignani, G.; Bettarini, S.; Calderini, G.; Carpinelli, M.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Morganti, M.; Neri, N.; Paoloni, E.; Rizzo, G.; Walsh, J. J.; Lopes Pegna, D.; Lu, C.; Olsen, J.; Smith, A. J. S.; Telnov, A. V.; Anulli, F.; Baracchini, E.; Cavoto, G.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Jackson, P. D.; Li Gioi, L.; Mazzoni, M. A.; Morganti, S.; Piredda, G.; Renga, F.; Voena, C.; Ebert, M.; Hartmann, T.; Schröder, H.; Waldi, R.; Adye, T.; Franek, B.; Olaiya, E. O.; Wilson, F. F.; Emery, S.; Esteve, L.; Hamel de Monchenault, G.; Kozanecki, W.; Vasseur, G.; Yèche, Ch.; Zito, M.; Allen, M. T.; Aston, D.; Bartoldus, R.; Benitez, J. F.; Cenci, R.; Coleman, J. P.; Convery, M. R.; Dingfelder, J. C.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Field, R. C.; Franco Sevilla, M.; Gabareen, A. M.; Graham, M. T.; Grenier, P.; Hast, C.; Innes, W. R.; Kaminski, J.; Kelsey, M. H.; Kim, H.; Kim, P.; Kocian, M. L.; Leith, D. W. G. S.; Li, S.; Lindquist, B.; Luitz, S.; Luth, V.; Lynch, H. L.; Macfarlane, D. B.; Marsiske, H.; Messner, R.; Muller, D. R.; Neal, H.; Nelson, S.; O'Grady, C. P.; Ofte, I.; Perl, M.; Ratcliff, B. N.; Roodman, A.; Salnikov, A. A.; Schindler, R. H.; Schwiening, J.; Snyder, A.; Su, D.; Sullivan, M. K.; Suzuki, K.; Swain, S. K.; Thompson, J. M.; Va'Vra, J.; Wagner, A. P.; Weaver, M.; West, C. A.; Wisniewski, W. J.; Wittgen, M.; Wright, D. H.; Wulsin, H. W.; Yarritu, A. K.; Young, C. C.; Ziegler, V.; Chen, X. R.; Liu, H.; Park, W.; Purohit, M. V.; White, R. M.; Wilson, J. R.; Burchat, P. R.; Edwards, A. J.; Miyashita, T. S.; Ahmed, S.; Alam, M. S.; Ernst, J. A.; Pan, B.; Saeed, M. A.; Zain, S. B.; Soffer, A.; Spanier, S. M.; Wogsland, B. J.; Eckmann, R.; Ritchie, J. L.; Ruland, A. M.; Schilling, C. J.; Schwitters, R. F.; Wray, B. C.; Drummond, B. W.; Izen, J. M.; Lou, X. C.; Bianchi, F.; Gamba, D.; Pelliccioni, M.; Bomben, M.; Bosisio, L.; Cartaro, C.; Della Ricca, G.; Lanceri, L.; Vitale, L.; Azzolini, V.; Lopez-March, N.; Martinez-Vidal, F.; Milanes, D. A.; Oyanguren, A.; Albert, J.; Banerjee, Sw.; Bhuyan, B.; Choi, H. H. F.; Hamano, K.; King, G. J.; Kowalewski, R.; Lewczuk, M. J.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Gershon, T. J.; Harrison, P. F.; Ilic, J.; Latham, T. E.; Mohanty, G. B.; Puccio, E. M. T.; Band, H. R.; Chen, X.; Dasu, S.; Flood, K. T.; Pan, Y.; Prepost, R.; Vuosalo, C. O.; Wu, S. L.

    2009-08-01

    We search for evidence of a light scalar boson in the radiative decays of the Υ(2S) and Υ(3S) resonances: Υ(2S,3S)→γA0, A0→μ+μ-. Such a particle 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 the mass range 0.212≤mA0≤9.3GeV in the samples of 99×106 Υ(2S) and 122×106 Υ(3S) decays collected by the BABAR detector at the SLAC PEP-II B factory and set stringent upper limits on the effective coupling of the b quark to the A0. We also limit the dimuon branching fraction of the ηb meson: B(ηb→μ+μ-)<0.9% at 90% confidence level.

  3. Radiative decay of the X(3872) as a mixed molecule-charmonium state in QCD sum rules

    SciTech Connect

    Nielsen, M.; Zanetti, C. M.

    2010-12-01

    We use QCD sum rules (QCDSR) to calculate the width of the radiative decay of the meson X(3872), assumed to be a mixture between charmonium and exotic molecular [cq][qc] states with J{sup PC}=1{sup ++}. We find that in a small range for the values of the mixing angle, 5 deg. {<=}{theta}{<=}13 deg., we get the branching ratio {Gamma}(X{yields}J/{psi}{gamma})/{Gamma}(X{yields}J/{psi}{pi}{sup +}{pi}{sup -})=0.19{+-}0.13, which is in agreement, with the experimental value. This result is compatible with the analysis of the mass and decay width of the mode J/{psi}(n{pi}) performed in the same approach.

  4. Radiative corrections of O(α ) to B- → V0 ℓ - bar{ν }_{ℓ } decays

    NASA Astrophysics Data System (ADS)

    Tostado, S. L.; Castro, G. López

    2016-09-01

    The O(α ) electromagnetic radiative corrections to the B^- → V^0 ℓ ^- bar{ν }_{ℓ } ( V is a vector meson and ℓ a charged lepton) decay rates are evaluated using the cutoff method to regularize virtual corrections and incorporating intermediate resonance states in the real-photon amplitude to extend the region of validity of the soft-photon approximation. The electromagnetic and weak form factors of hadrons are assumed to vary smoothly over the energies of virtual and real photons under consideration. The cutoff dependence of radiative corrections upon the scale Λ that separates the long- and short-distance regimes is found to be mild and is considered as an uncertainty of the calculation. Owing to partial cancellations of electromagnetic corrections evaluated over the three- and four-body regions of phase space, the photon-inclusive corrected rates are found to be dominated by the short-distance contribution. These corrections will be relevant for a precise determination of the b quark mixing angles by testing isospin symmetry when measurements of semileptonic rates of charged and neutral B mesons at the few percent level become available. For completeness, we also provide numerical values of radiative corrections in the three-body region of the Dalitz plot distributions of these decays.

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

    SciTech Connect

    Tan, Ping; /Wisconsin U., Madison

    2006-03-08

    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}|.

  6. Atomic radiations in the decay of medical radioisotopes: a physics perspective.

    PubMed

    Lee, B Q; Kibédi, T; Stuchbery, A E; Robertson, K A

    2012-01-01

    Auger electrons emitted in nuclear decay offer a unique tool to treat cancer cells at the scale of a DNA molecule. Over the last forty years many aspects of this promising research goal have been explored, however it is still not in the phase of serious clinical trials. In this paper, we review the physical processes of Auger emission in nuclear decay and present a new model being developed to evaluate the energy spectrum of Auger electrons, and hence overcome the limitations of existing computations.

  7. Novel nonperturbative approach for radiative B¯0(B¯s0)→J /ψ γ decays

    NASA Astrophysics Data System (ADS)

    Geng, Li-Sheng; Oset, Eulogio

    2016-07-01

    Radiative B¯ 0(B¯s 0)→J /ψ γ decays provide an interesting case to test our understanding of (non)perturbative QCD and eventually to probe physics beyond the standard model. Recently, the LHCb Collaboration reported an upper bound, updating the results of the BABAR Collaboration. Previous theoretical predictions based on QCD factorization or perturbative QCD have shown large variations due to different treatment of nonfactorizable contributions and meson-photon transitions. In this paper, we report on a novel approach to estimate the decay rates, which is based on a recently proposed model for B decays and the vector meson dominance hypothesis, widely tested in the relevant energy regions. The predicted branching ratios are Br [B¯ 0→J /ψ γ ]=(3.50 ±0.34-0.63+1.12)×10-8 and Br [B¯s 0→J /ψ γ ]=(7.20 ±0.68-1.30+2.31)×10-7 . The first uncertainty is systematic and the second is statistical, originating from the experimental B¯s 0→J /ψ ϕ branching ratio.

  8. Phenomenological study on the wino radiative decay in anomalous U(1){sup '} models

    SciTech Connect

    Fucito, Francesco; Lionetto, Andrea; Pacifici, Daniel Ricci; Racioppi, Antonio

    2010-12-01

    An extension of the standard model by at least one extra U(1) gauge symmetry has been investigated by many authors. In this paper we explore the possibility that this extra U(1) is anomalous. One possible signature of this model could be given by the photons produced in the decays of the next to lightest supersymmetric particle into the lightest supersymmetric particle.

  9. High-energy electrons from the muon decay in orbit: Radiative corrections

    DOE PAGES

    Szafron, Robert; Czarnecki, Andrzej

    2015-12-07

    We determine the Ο(α) correction to the energy spectrum of electrons produced in the decay of muons bound in atoms. We focus on the high-energy end of the spectrum that constitutes a background for the muon-electron conversion and will be precisely measured by the upcoming experiments Mu2e and COMET. As a result, the correction suppresses the background by about 20%.

  10. Applications of the tunneling method to particle decay and radiation from naked singularities

    NASA Astrophysics Data System (ADS)

    di Criscienzo, Roberto; Vanzo, Luciano; Zerbini, Sergio

    2010-05-01

    Following recent literature on dS instability in presence of interactions, we study the decay of massive particles in general FRW models and the emission from naked singularities either associated with 4 D charged black holes or 2 D shock waves, by means of the Hamilton-Jacobi tunneling method. It is shown that the two-dimensional semiclassical tunneling amplitude from a naked singularity computed in that way is the same as the one-loop result of quantum field theory.

  11. Corrected Article: "Experimental observation of nonspherically-decaying radiation from a rotating superluminal source" [J. Appl. Phys. 96, 4614 (2004)

    NASA Astrophysics Data System (ADS)

    Ardavan, A.; Hayes, W.; Singleton, J.; Ardavan, H.; Fopma, J.; Halliday, D.

    2004-12-01

    We describe the experimental implementation of a superluminal (i.e., faster than light in vacuo) polarization current distribution that both oscillates and undergoes centripetal acceleration. Theoretical treatments predict that the radiation emitted by each volume element of the superluminally moving distribution pattern will comprise a Čerenkov-like envelope with two sheets that meet along a cusp. Correspondingly, the emission from the experimental machine is found to be tightly beamed in both the azimuthal and polar directions. The beaming is frequency independent and has a sharply defined and unchanging geometry determined only by the speed and path of the moving distribution pattern, i.e., by the parameters governing the structure of the Čerenkov-like envelopes. In addition, over a restricted range of angles, we detect the presence of cusps in the emitted radiation. These, which are due to the focusing of wave fronts on a propagating space curve, result in the reception, during a short time period, of radiation emitted over a considerably longer period of (retarded) source time. The intensity of the radiation at these angles was observed to decline more slowly with increasing distance from the source than would the emission from a conventional antenna. The angular distribution of the emitted radiation and the properties associated with the cusps are in good quantitative agreement with theoretical models of superluminal sources once the effect of reflections from the earth's surface are taken into account. In particular, the prediction that the beaming and the slow decay should extend into the far zone has been tested to several hundred Fresnel distances (Rayleigh ranges). The excellent agreement between the theoretical calculations and the data suggests that the apparatus achieves precise and reproducible control of the polarization current and that similar machines could be of general interest for studying and utilizing the novel effects associated with

  12. On the origin of the pion-decay radiation in the 1982 June 3 solar flare

    NASA Technical Reports Server (NTRS)

    Ramaty, R.; Murphy, R. J.; Dermer, C. D.

    1987-01-01

    The June 3, 1982 flare produced a wealth of observed gamma-ray, energetic particle, and neutron emissions. It is shown that the predictions of an interaction model developed for the June 3 flare by Murphy, Dermer, and Ramaty (1987) compare favorably with new data on the time-dependent flux on pion-decay emission from this flare. It is concluded that the particles which produced the bulk of the pions could have the same origin as the particle observed in interplanetary space from the June 3 flare.

  13. Lifetime and Polarization of the Radiative Decay of Excitons, Biexcitons, and Trions in CdSe Nanocrystal Quantum Dots

    SciTech Connect

    Califano, M.; Franceschetti, A.; Zunger, A.

    2007-01-01

    Using the pseudopotential configuration-interaction method, we calculate the intrinsic lifetime and polarization of the radiative decay of single excitons (X), positive and negative trions (X{sup +} and X{sup -}), and biexcitons (XX) in CdSe nanocrystal quantum dots. We investigate the effects of the inclusion of increasingly more complex many-body treatments, starting from the single-particle approach and culminating with the configuration-interaction scheme. Our configuration-interaction results for the size dependence of the single-exciton radiative lifetime at room temperature are in excellent agreement with recent experimental data. We also find the following. (i) Whereas the polarization of the bright exciton emission is always perpendicular to the hexagonal c axis, the polarization of the dark exciton switches from perpendicular to parallel to the hexagonal c axis in large dots, in agreement with experiment. (ii) The ratio of the radiative lifetimes of mono- and biexcitons (X):(XX) is {approx}1:1 in large dots (R=19.2 {angstrom}). This ratio increases with decreasing nanocrystal size, approaching 2 in small dots (R=10.3 {angstrom}). (iii) The calculated ratio (X{sup +}):(X{sup -}) between positive and negative trion lifetimes is close to 2 for all dot sizes considered.

  14. Radiative Dileptonic Decays of B-Meson in the General Two Higgs Doublet Model

    NASA Astrophysics Data System (ADS)

    Erkol, G.; Turan, G.

    2002-05-01

    We investigate the exclusive B → γ ℓ + ℓ - decay in the general two Higgs Doublet Model (model III) including the neutral Higgs boson effects with an emphasis on possible CP-violating effects. For this decay, we analyze the dependencies of the forward-backward asymmetry of the lepton pair, AFB, CP-violating asymmetry, ACP, and the CP-violating asymmetry in forward-backward asymmetry, ACP(AFB), on the model parameters and also on the neutral Higgs boson effects. We have found that AFB˜ 10-1, 10-2, ACP˜ 10-2, 10-1 and ACP(AFB) ˜ 10-2, 10-1 depending on the relative magnitude of the Yukawa couplings bar ξ N,ttU and bar ξ N,bbD in the model III. We also observe that these physical quantities are sensitive to the model parameters and neutral Higgs boson effects are quite sizable for some values of the coupling bar ξ N,τ τ D.

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

    SciTech Connect

    Aubert, B

    2009-06-02

    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.

  16. Search for dimuon decays of a light scalar boson in radiative transitions Upsilon-->gammaA0.

    PubMed

    Aubert, B; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Martinelli, M; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Petigura, E; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Ongmongkolku, P; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Wilson, R J; Feltresi, E; Hauke, A; Jasper, H; Karbach, T M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Volk, A; Bernard, D; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Fioravanti, E; Franchini, P; Luppi, E; Munerato, M; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Guido, E; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Chaisanguanthum, K S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Tibbetts, M; Behera, P K; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Derkach, D; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Malaescu, B; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Hafner, A; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Schram, M; Biassoni, P; Lazzaro, A; Lombardo, V; Palombo, F; Stracka, S; Bauer, J M; Cremaldi, L; Godang, R; Kroeger, R; Sonnek, P; Summers, D J; Zhao, H W; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; del Amo Sanchez, P; Ben-Haim, E; Bonneaud, G R; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Marchiori, G; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Allen, M T; Aston, D; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Franco Sevilla, M; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Young, C C; Ziegler, V; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Burchat, P R; Edwards, A J; Miyashita, T S; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Soffer, A; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Wray, B C; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; King, G J; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Puccio, E M T; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Prepost, R; Vuosalo, C O; Wu, S L

    2009-08-21

    We search for evidence of a light scalar boson in the radiative decays of the Upsilon(2S) and Upsilon(3S) resonances: Upsilon(2S,3S)-->gammaA0, A0-->mu+mu-. Such a particle 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 the mass range 0.212 < or = mA0 < or = 9.3 GeV in the samples of 99 x 10(6) Upsilon(2S) and 122 x 10(6) Upsilon(3S) decays collected by the BABAR detector at the SLAC PEP-II B factory and set stringent upper limits on the effective coupling of the b quark to the A0. We also limit the dimuon branching fraction of the etab meson: B(etab-->mu+mu-)<0.9% at 90% confidence level. PMID:19792717

  17. Roles of Interfering Radiation Emitted from Decaying Pulses Obeying Soliton Equations Belonging to the Ablowitz-Kaup-Newell-Segur Systems

    NASA Astrophysics Data System (ADS)

    Fujishima, Hironobu; Yajima, Tetsu

    2015-06-01

    The nonlinear Schrödinger (NLS) equation under the box-type initial condition, which models general multiple pulses deviating from pure solitons, is analyzed. Following the approximation by splitting the initial pulse into many small bins [G. Boffetta and A. R. Osborne, http://dx.doi.org/10.1016/0021-9991(92)90370-E, J. Comp. Phys. 102, 252 (1992)], we can analyze the Zakharov-Shabat eigenvalue problem to construct transfer matrices connecting the Jost functions in each interval without direct numerical computation. We can obtain analytical expressions for the scattering data that describe interfering radiation emitted from initial pulses. The number of solitons that appear in the final stage is predicted theoretically, and the condition generating an unusual wave such as a double-pole soliton is derived. Numerical analyses under box-type initial conditions are also performed to show that the interplay between the tails from decaying pulses can affect the asymptotic profile.

  18. Fluorescence Quenching of Alpha-Fetoprotein by Gold Nanoparticles: Effect of Dielectric Shell on Non-Radiative Decay

    NASA Astrophysics Data System (ADS)

    Zhu, Jian; Li, Jian-Jun; Wang, A.-Qing; Chen, Yu; Zhao, Jun-Wu

    2010-09-01

    Fluorescence quenching spectrometry was applied to study the interactions between gold colloidal nanoparticles and alpha-fetoprotein (AFP). Experimental results show that the gold nanoparticles can quench the fluorescence emission of adsorbed AFP effectively. Furthermore, the intensity of fluorescence emission peak decreases monotonously with the increasing gold nanoparticles content. A mechanism based on surface plasmon resonance-induced non-radiative decay was investigated to illuminate the effect of a dielectric shell on the fluorescence quenching ability of gold nanoparticles. The calculation results show that the increasing dielectric shell thickness may improve the monochromaticity of fluorescence quenching. However, high energy transfer efficiency can be obtained within a wide wavelength band by coating a thinner dielectric shell.

  19. Fluorescence Quenching of Alpha-Fetoprotein by Gold Nanoparticles: Effect of Dielectric Shell on Non-Radiative Decay.

    PubMed

    Zhu, Jian; Li, Jian-Jun; Wang, A-Qing; Chen, Yu; Zhao, Jun-Wu

    2010-06-15

    Fluorescence quenching spectrometry was applied to study the interactions between gold colloidal nanoparticles and alpha-fetoprotein (AFP). Experimental results show that the gold nanoparticles can quench the fluorescence emission of adsorbed AFP effectively. Furthermore, the intensity of fluorescence emission peak decreases monotonously with the increasing gold nanoparticles content. A mechanism based on surface plasmon resonance-induced non-radiative decay was investigated to illuminate the effect of a dielectric shell on the fluorescence quenching ability of gold nanoparticles. The calculation results show that the increasing dielectric shell thickness may improve the monochromaticity of fluorescence quenching. However, high energy transfer efficiency can be obtained within a wide wavelength band by coating a thinner dielectric shell.

  20. Measurements of the production of P-wave charmonium states through radiative decays at the ATLAS experiment

    NASA Astrophysics Data System (ADS)

    Marcisovsky, Michal

    2014-04-01

    The production cross sections of the χc1 and χc2 charmonium states are measured in pp collisions at √s = 7 TeV using 4.5 fb-1 of integrated luminosity recorded by the ATLAS detector at the LHC. The χc states are reconstructed via the radiative decay χc → J/ψ(μ+μ-)γ, where the photons are reconstructed using γ → e+ e- conversion in the detector material. Differential production cross sections for prompt and non-prompt χc1,2 are presented, as well as the fraction of inclusive J/ψ produced by feed-down from the χc states. The results are compared with a range of theoretical predictions. The branching fraction of ℬ (B+ → χc1K+) is measured using the same dataset and χc event selection.

  1. A New Measurement of {eta}{sub b}(1S) From {Upsilon}(3S) Radiative Decay at CLEO

    SciTech Connect

    Dobbs, Sean

    2010-08-05

    Using CLEO data, we report on the confirmation of the {eta}{sub b}({sup 1}S{sub 0}) ground state of bottomonium in the radiative decay {Upsilon}(3S){yields}{gamma}{eta}{sub b} We determine its mass to be M({eta}{sub b}) = 9391.8{+-}6.6{+-}2.1 MeV, which corresponds to the hyperfine splitting {Delta}M{sub hf}(1S) = 68.5{+-}6.6{+-}2.0 MeV, and the branching fraction B({Upsilon}(3S){gamma}{eta}{sub b}) = (7.1{+-}1.8{+-}1.1)x10{sup -4}. These results agree with those previously reported by BaBar.

  2. Astrophysical data on 5 eV to 1 keV radiation from the radiative decay of fundamental particles - Current limits and prospects for improvement

    NASA Technical Reports Server (NTRS)

    Bowyer, Stuart; Malina, Roger F.

    1986-01-01

    Line emission from the decay of fundamental particles, integrated over cosmological distances, can give rise to detectable spectral features in the diffuse astronomical background between 5 eV and 1 keV. Spectroscopic observations may allow these features to be separated from line emission from the numerous local sources of radiation. The current observational status and existing evidence for such features are reviewed. No definitive detections of nongalactic line features have been made. Several local sources of background mask the features at many wavelengths and confuse the interpretation of the data. No systematic spectral observations have been carried out to date. Upcoming experiments which can be expected to provide significantly better constraints on the presence of spectral features in the diffuse background from 5 eV to 1 keV are reviewed.

  3. The Radiative Decay of Green and Red Photoluminescent Phosphors: An Undergraduate Kinetics Experiment for Materials Chemistry

    ERIC Educational Resources Information Center

    Esposti, C. Degli; Bizzocchi, L.

    2008-01-01

    This article describes a laboratory experiment that allows the students to investigate the radiative properties of the green and red emitting phosphors that are employed in commercial fluorescent lamps. Making use of a spectrofluorometer, students first record the emission spectrum of a fluorescent lamp under normal operating conditions, and then…

  4. Photogenerated excitons in plain core CdSe nanocrystals with unity radiative decay in single channel: the effects of surface and ligands.

    PubMed

    Gao, Yuan; Peng, Xiaogang

    2015-04-01

    A systematic and reproducible method was developed to study the decay dynamics of an exciton, a photogenerated electron-hole pair, in semiconductor nanocrystals in solution. Results revealed that the excitons in plain core CdSe nanocrystals in either zinc-blende or wurtzite or mixed lattice structures could be reproducibly prepared to decay radiatively in unity quantum yield and in single channel. The single-channel lifetime was found to increase monotonically by increasing size of the CdSe nanocrystals, with zinc-blende ones increasing in a relatively slow pace. Surface inorganic stoichiometry was found to be a sensitive parameter to affect the exciton decay dynamics for all crystal structures with different sizes. Excess Se (Cd) sites on the surface were found to induce short (long) lifetime channels for the excitons. Both types of traps reduced the quantum yield of the radiative decay of the excitons, and the hole traps associated with Se sites were nearly not emissive. With optimal surface inorganic stoichiometry, primary amines were identified as "ideal" organic ligands for CdSe core nanocrystals to achieve unity radiative decay of excitons in single channel in comparison to other types of neutral ligands commonly applied in the field.

  5. Measurement of radiative J/psi decays in KK-bar states

    SciTech Connect

    Augustin, J.E.; Calcaterra, A.; Cosme, G.; Couchot, F.; Dudelzak, B.; Fulda, F.; Grosdidier, G.; Jean-Marie, B.; Jullian, S.; Lalanne, D.; and others

    1988-05-30

    The decays Jpsi..--> gamma..K/sup +/K/sup -/ and ..gamma..K/sub S//sup 0/K/sub S//sup 0/ have been studied using 8.6 x 10/sup 6/ Jpsi's produced in the DM2 detector. Clean and well separated signals of f/sub 2//sup '/(1525) and f/sub 2/(1720) are observed in both channels and the measured product branching ratios are given. In neither channel is the xi(2230) seen; upper limits are given. Last, an as-yet-unexplained production of events is observed in the K/sub S//sup 0/K/sub S//sup 0/ mass spectrum between 2.0 and 2.5 GeVc/sup 2/. .AE

  6. Observation of chicJ radiative decays to light vector mesons.

    PubMed

    Bennett, J V; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tan, B J Y; Tomaradze, A; Libby, J; Martin, L; Powell, A; Wilkinson, G; Ecklund, K M; Love, W; Savinov, V; Mendez, H; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Naik, P; Rademacker, J; Asner, D M; Edwards, K W; Reed, J; Briere, R A; Tatishvili, G; Vogel, H; Rosner, J L; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Galik, R S; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hunt, J M; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Ledoux, J; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J

    2008-10-10

    Using a total of 2.74 x 10(7) decays of the psi(2S) collected with the CLEO-c detector, we present a study of chi(cJ)-->gammaV, where V=rho(0), omega, phi. The transitions chi(c1)-->gammarho(0 and chi(c1)-->gammaomega are observed with B(chi(c1)-->gammarho(0))=(2.43+/-0.19+/-0.22) x 10(-4) and B(chi(c1)-->gammaomega)=(8.3+/-1.5+/-1.2) x 10(-5). In the chi(c1)-->gammarho(0) transition, the final state meson is dominantly longitudinally polarized. Upper limits on the branching fractions of other chi(cJ) states to light vector mesons are presented. PMID:18999588

  7. Self-consistent solitons for vacuum decay in radiatively generated potentials

    NASA Astrophysics Data System (ADS)

    Garbrecht, Björn; Millington, Peter

    2015-12-01

    We use a Green's function approach in order to develop a method for calculating the tunneling rate between radiatively generated nondegenerate vacua. We apply this to a model that exhibits spontaneous symmetry breaking via the Coleman-Weinberg mechanism, where we determine the self-consistent tunneling configuration and illustrate the impact of gradient effects that arise from accounting for the underlying space-time inhomogeneity.

  8. Test of the linear-NO threshold theory of radiation carcinogenesis for inhaled radon decay products

    SciTech Connect

    Cohen, B.L.

    1995-02-01

    Data on lung cancer mortality rates vs. average radon concentration in homes for 1,601 U.S. counties are used to test the linear-no threshold theory. The widely recognized problems with ecological studies, as applied to this work, are addressed extensively. With or without corrections for variations in smoking prevalence, there is a strong tendency for lung cancer rates to decrease with increasing radon exposure, in sharp contrast to the increase expected from the theory. The discrepancy in slope is about 20 standard deviations. It is shown that uncertainties in lung cancer rates, radon exposures, and smoking prevalence are not important and that confounding by 54 socioeconomic factors, by geography, and by altitude and climate can explain only a small fraction of the discrepancy. Effects of known radon-smoking prevalence correlations-rural people have higher radon levels and smoke less than urban people, and smokers are exposed to less radon than non-smokers-are calculated and found to be trivial. In spite of extensive efforts, no potential explanation for the discrepancy other than failure of the linear-no threshold theory for carcinogenesis from inhaled radon decay products could be found. 46 refs., 2 figs., 7 tabs.

  9. Radiative decay engineering 5: metal-enhanced fluorescence and plasmon emission

    PubMed Central

    Lakowicz, Joseph R.

    2009-01-01

    Metallic particles and surfaces display diverse and complex optical properties. Examples include the intense colors of noble metal colloids, surface plasmon resonance absorption by thin metal films, and quenching of excited fluorophores near the metal surfaces. Recently, the interactions of fluorophores with metallic particles and surfaces (metals) have been used to obtain increased fluorescence intensities, to develop assays based on fluorescence quenching by gold colloids, and to obtain directional radiation from fluorophores near thin metal films. For metal-enhanced fluorescence it is difficult to predict whether a particular metal structure, such as a colloid, fractal, or continuous surface, will quench or enhance fluorescence. In the present report we suggest how the effects of metals on fluorescence can be explained using a simple concept, based on radiating plasmons (RPs). The underlying physics may be complex but the concept is simple to understand. According to the RP model, the emission or quenching of a fluorophore near the metal can be predicted from the optical properties of the metal structures as calculated from electrodynamics, Mie theory, and/or Maxwell’s equations. For example, according to Mie theory and the size and shape of the particle, the extinction of metal colloids can be due to either absorption or scattering. Incident energy is dissipated by absorption. Far-field radiation is created by scattering. Based on our model small colloids are expected to quench fluorescence because absorption is dominant over scattering. Larger colloids are expected to enhance fluorescence because the scattering component is dominant over absorption. The ability of a metal’s surface to absorb or reflect light is due to wavenumber matching requirements at the metal–sample interface. Wavenumber matching considerations can also be used to predict whether fluorophores at a given distance from a continuous planar surface will be emitted or quenched. These

  10. Heavy quark signals from radiative corrections to the Z{sup '} boson decay in 3-3-1 models

    SciTech Connect

    Martinez, R.; Ochoa, F.

    2009-10-01

    One-loop corrections to the Z{sup '} decay width are derived and analyzed in the framework of the general form of the 3-3-1 models. We identify two important sources of corrections: oblique corrections associated to the Z{sup '} propagator through vacuum polarizations induced by virtual particle-antiparticle pairs of new heavy quarks J, and vertex corrections to the Z{sup '}qq vertex through virtual exchange of new K{sup Q{sub 1,2}} gauge bosons. Fixing a specific renormalization scheme, we obtain dominant oblique corrections that exhibit a quadratic dependence on the J quark mass, which are absorbed into two oblique parameters: a global parameter {rho}{sub f}{sup '} which modify the Z{sup '} decay width, and a parameter {kappa}{sub f}{sup '} that define effective Z{sup '} couplings. Numerical results in an specific 3-3-1 model gives a strong contribution of the oblique corrections from about 1.3% in the d(s) quark channel to 10.5% in the neutrino channel, for m{sub J}=2 TeV. The vertex corrections contribute to the oblique corrections up to 1.4% for the same channel and m{sub J} value. For pp collisions at the CERN LHC collider, we find that the corrections significantly modify the shape of the cross section distributions for e{sup +}e{sup -} and tt final states, where the distributions including the radiative corrections increases up to 1.23 times the tree-level distribution for the dielectron events and to 1.07 for the top events when m{sub J}=3 TeV.

  11. Absolute cross sections and branching ratios for the radiative decay of doubly excited helium determined by photon-induced fluorescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Mickat, S.; Schartner, K.-H.; Kammer, Sv; Schill, R.; Werner, L.; Klumpp, S.; Ehresmann, A.; Schmoranzer, H.; Sukhorukov, V. L.

    2005-08-01

    The decay of doubly excited helium states below the N = 2 threshold, cascading radiatively over three steps, were investigated using the photon-induced fluorescence spectroscopy (PIFS) at BESSY II. Absolute cross sections as the product of the resonance excitation cross section of the doubly excited states and their fluorescence rate to decay into the singly excited 1sms(1S) and 1smd(1D) states were measured. The experiments showed that the (sp,2n+)(1P) states decay predominantly into the 1sns(1S) states, whereas the (pd,2n)(1P) states prefer to decay into the 1snd(1D) states. For the (sp,2n-)(1P) states with n = 4, 5 and 6 we observed a broad and complex decay pattern. In addition the angular distribution of the fluorescence radiation was measured. The results are in good agreement with theoretical predictions. Furthermore, the weakening of the LS coupling scheme and the mixing between singlet and triplet states in helium was confirmed by observation of the 1s6d(3D0,1,2) → 1s2p(3P0,1,2) transition on a doubly excited singlet state.

  12. Modeling of Iron K Lines: Radiative and Auger Decay Data for Fe II-Fe IX

    NASA Technical Reports Server (NTRS)

    Palmeri, P.; Mendoza, C.; Kallman, T. R.; Bautista, M. A.; Melendez, M.

    2003-01-01

    A detailed analysis of the radiative and Auger de-excitation channels of K-shell vacancy states in Fe II-Fe IX has been carried out. Level energies, wavelengths, A-values, Auger rates and fluorescence yields have been calculated for the lowest fine-structure levels populated by photoionization of the ground state of the parent ion. Different branching ratios, namely K alpha 2/K alpha 1, K beta/K alpha, KLM/KLL, KMM/KLL, and the total K-shell fluorescence yields, omega(sub k), obtained in the present work have been compared with other theoretical data and solid-state measurements, finding good general agreement with the latter. The Kalpha 2/K alpha l ratio is found to be sensitive to the excitation mechanism. From these comparisons it has been possible to estimate an accuracy of approx.10% for the present transition probabilities.

  13. Radiative decay effects influence the local electromagnetic response of the monolayer graphene with surface corrugations in terahertz range

    NASA Astrophysics Data System (ADS)

    Firsov, Yu. A.; Firsova, N. E.

    2015-07-01

    We continue the study of surface corrugations influence on the monolayer graphene local electromagnetic response in terahertz range we started earlier. The effects of radiative decay, double-valley structure of charge carriers spectrum in graphene and the "breathing" corrugated surface form induced synthetic electric fields are taken into account. To fulfill this program the generalized nonlinear self-consistent-field equation is obtained. In case of weak external alternating electric field E→ext (t) =E→0 cos ωt for the obtained equation in linear approximation on the external electric field the exact solution is found. It shows that in this case we get local induced current paths depending on the surface form z = h (x , y) . This theoretical result qualitatively explains the corresponding experiments with local current patterns depending on the point by corrugations influence. The induced currents formula was obtained without using fully quantum approach which is necessary for theoretical description of such phenomenon in graphene nanoribbons. Besides the formulae obtained in the present paper could become the basis of the new method of the imaging of surface corrugations form for given experimental picture of local current paths.

  14. Updated Next-to-Next-to-Leading-Order QCD Predictions for the Weak Radiative B-Meson Decays.

    PubMed

    Misiak, M; Asatrian, H M; Boughezal, R; Czakon, M; Ewerth, T; Ferroglia, A; Fiedler, P; Gambino, P; Greub, C; Haisch, U; Huber, T; Kamiński, M; Ossola, G; Poradziński, M; Rehman, A; Schutzmeier, T; Steinhauser, M; Virto, J

    2015-06-01

    Weak radiative decays of the B mesons belong to the most important flavor changing processes that provide constraints on physics at the TeV scale. In the derivation of such constraints, accurate standard model predictions for the inclusive branching ratios play a crucial role. In the current Letter we present an update of these predictions, incorporating all our results for the O(α_{s}^{2}) and lower-order perturbative corrections that have been calculated after 2006. New estimates of nonperturbative effects are taken into account, too. For the CP- and isospin-averaged branching ratios, we find B_{sγ}=(3.36±0.23)×10^{-4} and B_{dγ}=(1.73_{-0.22}^{+0.12})×10^{-5}, for E_{γ}>1.6 GeV. Both results remain in agreement with the current experimental averages. Normalizing their sum to the inclusive semileptonic branching ratio, we obtain R_{γ}≡(B_{sγ}+B_{dγ})/B_{cℓν}=(3.31±0.22)×10^{-3}. A new bound from B_{sγ} on the charged Higgs boson mass in the two-Higgs-doublet-model II reads M_{H^{±}}>480 GeV at 95% C.L. PMID:26196614

  15. Four-body Dalitz plot contribution to the radiative corrections in Kl3 0 decays and its role in the determination of |Vu s|

    NASA Astrophysics Data System (ADS)

    Neri, M.; Martínez, A.; Juárez-León, C.; Torres, J. J.; Flores-Mendieta, Rubén

    2016-09-01

    The four-body contribution of the model-independent radiative corrections to the Dalitz plot of the semileptonic decays of neutral kaons are computed to order (α /π )(q /M1) , where q is the momentum transfer and M1 is the kaon mass. The final result is presented in two forms. The first one is given in terms of the triple integration of the bremsstrahlung photon ready to be performed numerically; the second one is a fully analytical expression. This paper is organized to make it accessible and reliable in the analysis of the Dalitz plot of precision experiments involving kaons and is not compromised to fixing the form factors at predetermined values. As a byproduct, gathering together three- and four-body contributions of radiative corrections yields, through a least-squares fit to the measured kaon decay rates, the value f+K0π-|Vu s|=0.2168 (3 ) .

  16. Refractive index effects on the oscillator strength and radiative decay rate of 2,3-diazabicyclo[2.2.2]oct-2-ene.

    PubMed

    Mohanty, Jyotirmayee; Nau, Werner M

    2004-01-01

    The photophysical properties of 2,3-diazabicyclo[2.2.2]oct-2-ene (DBO) were determined in 15 solvents, two supramolecular hosts (cucurbit[7]uril and beta-cyclodextrin) as well as in the gas phase. The oscillator strength and radiative decay rate of DBO as a function of refractive index i.e. polarizability have been analyzed. The oscillator strength increases by a factor of 10 upon going from the gas phase to the most polarizable carbon disulfide, while the corresponding radiative decay rates increase by a factor of 40. There is a good empirical correlation between the oscillator strength of the weakly allowed n,pi* transition of DBO and the reciprocal bulk polarizability, which can be employed to assess the polarizability of unknown microheterogeneous environments. A satisfactory correlation between the radiative decay rate and the square of the refractive index is also found, as previously documented for chromophores with allowed transitions. However, the correlation improves significantly when the oscillator strength is included in the correlation, which demonstrates the importance of this factor in the Strickler-Berg equation for chromophores with forbidden or weakly allowed transitions, for which the oscillator strength may be strongly solvent dependent. The radiative decay rate of DBO in two supramolecular assemblies has been determined, confirming the very low polarizability inside the cucurbituril cavity, in between perfluorohexane and the gas phase. The fluorescence quantum yield of DBO in the gas phase has been remeasured (5.1 +/- 0.5%) and was found to fall one full order of magnitude below a previously reported value.

  17. An analytical method for estimating the {sup 14}N nuclear quadrupole resonance parameters of organic compounds with complex free induction decays for radiation effects studies

    SciTech Connect

    Iselin, L.H.

    1992-12-31

    The use of {sup 14}N nuclear quadrupole resonance (NQR) as a radiation dosimetry tool has only recently been explored. An analytical method for analyzing {sup 14}N NQR complex free induction decays is presented with the background necessary to conduct pulsed NQR experiments. The {sup 14}N NQR energy levels and possible transitions are derived in step-by-step detail. The components of a pulsed NQR spectrometer are discussed along with the experimental techniques for conducting radiation effects experiments using the spectrometer. Three data analysis techniques -- the power spectral density Fourier transform, state space singular value decomposition (HSVD), and nonlinear curve fitting (using the downhill simplex method of global optimization and the Levenberg-Marquart method) -- are explained. These three techniques are integrated into an analytical method which uses these numerical techniques in this order to determine the physical NQR parameters. Sample data sets of urea and guanidine sulfate data are used to demonstrate how these methods can be employed to analyze both simple and complex free induction decays. By determining baseline values for biologically significant organics, radiation effects on the NQR parameters can be studied to provide a link between current radiation dosimetry techniques and the biological effects of radiation.

  18. A comparison of radiative capture with decay gamma-ray method in bore hole logging for economic minerals

    USGS Publications Warehouse

    Senftle, F.E.; Moxham, R.M.; Tanner, A.B.

    1972-01-01

    The recent availability of borehole logging sondes employing a source of neutrons and a Ge(Li) detector opens up the possibility of analyzing either decay or capture gamma rays. The most efficient method for a given element can be predicted by calculating the decay-to-capture count ratio for the most prominent peaks in the respective spectra. From a practical point of view such a calculation must be slanted toward short irradiation and count times at each station in a borehole. A simplified method of computation is shown, and the decay-to-capture count ratio has been calculated and tabulated for the optimum value in the decay mode irrespective of the irradiation time, and also for a ten minute irradiation time. Based on analysis of a single peak in each spectrum, the results indicate the preferred technique and the best decay or capture peak to observe for those elements of economic interest. ?? 1972.

  19. Search for a light Higgs boson decaying to two gluons or ss̄ in the radiative decays of Υ(1S)

    DOE PAGES

    Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Stugu, B.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; et al

    2013-08-06

    We search for the decay Υ(1S)→γA⁰, A⁰→gg or ss̄, where A⁰ is the pseudoscalar light Higgs boson predicted by the next-to-minimal supersymmetric Standard Model. We use a sample of (17.6±0.3)×10⁶ Υ(1S) mesons produced in the BABAR experiment via e⁺e⁻→Υ(2S)→π⁺π⁻Υ(1S). We see no significant signal and set 90%-confidence-level upper limits on the product branching fraction B(Υ(1S)→γA⁰)·B(A⁰→gg or ss̄) ranging from 10⁻⁶ to 10⁻² for A⁰ masses in the range 0.5–9.0 GeV/c².

  20. The Observation of the Weak Radiative Hyperon Decay XI0 ---> Lambda0 pi0 gamma at KTeV/E799, Fermilab

    SciTech Connect

    Ping, Huican

    2005-01-01

    The large sample of {Xi}{sup 0} hyperons available at KTeV 799 provides an opportunity to search for the Weak Radiative Hyperon Decay {Xi}{sup 0} {yields} {Lambda}{sup 0}{pi}{sup 0}{gamma}. They present a branching fraction measurement of {Xi}{sup 0} {yields} {Lambda}{sup 0}{pi}{sup 0}{gamma} based on the E799-II experiment data-taking in 1999 at KTeV, Fermilab. They used the principal decay of {Xi}{sup 0} {yields} {Lambda}{sup 0}{pi}{sup 0} where {Lambda} decays to a proton and a {pi}{sup -} as the flux normalization mode. This is the first observation of this interesting decay mode. 4 candidate events are found in the data. The branching ratio at 90% confidence level has been measured to be (1.67{sub -0.80}{sup +1.45}(stat.) {+-} 0.50(syst.)) x 10{sup -5} or (1.67{sub -0.69}{sup +1.16}(stat.) {+-} 0.50(syst.)) x 10{sup -5} at 68.27% confidence level.

  1. Cellular lung dosimetry for inhaled radon decay products as a base for radiation-induced lung cancer risk assessment. II. Microdosimetric calculations.

    PubMed

    Hofmann, W

    1982-01-01

    Lung dose calculations for inhaled radon decay products presented in part I have revealed that mean basal cell doses are significantly dependent on various personal and environmental factors. Whereas these macroscopic dosimetric methods have been applied with great success to radiation protection problems, the interpretation of radiobiological effects, such as lung cancer incidence, needs some refinement of these methods. Energy deposition at the microscopic level as the physical input quantity and radiation carcinogenesis as the biological endpoint are by nature stochastic processes. Therefore, a microdosimetric model was developed taking into consideration the randomness of physical and biological parameters involved, Part II of the paper presents results on specific energy distributions in lung cells, demonstrating that single event density distributions together with the number of cells receiving single hits represent more appropriate parameters than mean radiation doses. PMID:6285407

  2. Search for X-ray induced decay of the 31-yr isomer of 178Hf using synchrotron radiation

    SciTech Connect

    Ahmad, I; Banar, J C; Becker, J A; Bredeweg, T A; Cooper, J R; Gemmell, D S; Kraemer, A; Mashayekhi, A; McNabb, D P; Miller, G G; Moore, E F; Palmer, P; Pangault, L N; Rundberg, R S; Schiffer, J P; Shastri, S D; Wang, T F; Wilhelmy, J B

    2004-09-13

    Isomeric {sup 178}Hf (t{sub 1/2} = 31 yr, E{sub x} = 2.446 MeV, J{sup {pi}} = 16{sup +}) was bombarded by a white beam of x-rays from the Advanced Photon Source at Argonne National Laboratory. A search was made for x-ray induced decay of the isomer by detecting prompt and delayed {gamma} rays associated with the decay. No induced decay was observed. Upper limits for such a process for x-ray energies between 7-100 keV were set. The limits between 7 and 30 keV are below {approx} 3 x 10{sup -27} cm{sup 2}-keV for induced decay that bypasses the 4-s isomer and {approx} 5 x 10{sup -27} cm{sup 2}-keV for induced decay that is delayed through this isomer, orders of magnitude below values at which induced decay was reported previously. These limits are consistent with what is known about the properties of atomic nuclei.

  3. Theoretical Insights into the Photo-Deactivation of Emitting Triplet Excited State of (C^N)Pt(O^O) Complexes: Radiative and Nonradiative Decay Processes.

    PubMed

    Xu, Yanyan; Luo, Yafei; Li, Ming; He, Rongxing; Shen, Wei

    2016-09-01

    In this study, density functional theory (DFT) and time-dependent DFT were employed to elucidate the photo-deactivation mechanisms of (C^N)Pt(O^O) complexes 1-4 (where C^N = 2-phenylpyridine derivatives, O^O = dipivolylmethanoate). To make thorough understanding of the radiative decay, the singlet-triplet splitting energies ΔE(Sn-T1) (n = 1, 2, 3, 4, ...), transition dipole moment μ(Sn) for S0-Sn transitions and the spin-orbit coupling (SOC) matrix elements ⟨T1|HSOC|Sn⟩ were all calculated. Moreover, the spin-orbit coupling between T1 and S0 ⟨T1|HSOC|S0⟩ and Huang-Rhys factors were calculated to estimate the temperature-independent nonradiative decay processes. Meanwhile, the thermal deactivation via metal-centered (3)MC was described to analyze the temperature-dependent nonradiative decay processes. As a result, the effective SOC interaction between the lowest triplet and singlet excited states successfully rationalize why complexes 1 and 3 have higher radiative decay rate constant than that of complex 2, while the larger ⟨T1|HSOC|S0⟩ and lower energy barrier for thermal deactivation in 3 reasonably explains why 3 has larger nonradiative rate than that of 1 and 2. Consequently, it can be concluded that it is the ⟨T1|HSOC|S0⟩ and thermal population of (3)MC that account for the nonemissive behavior of (C^N)Pt(O^O) complexes, and controlling π-conjugation is an efficient method for tuning phosphorescence properties of transition-metal complexes. PMID:27517617

  4. Search for a light Higgs resonance in radiative decays of the ϒ (1 S ) with a charm tag

    NASA Astrophysics Data System (ADS)

    Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Stugu, B.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lee, M. J.; Lynch, G.; Koch, H.; Schroeder, T.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; So, R. Y.; Khan, A.; Blinov, V. E.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Kravchenko, E. A.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Lankford, A. J.; Dey, B.; Gary, J. W.; Long, O.; Franco Sevilla, M.; Hong, T. M.; Kovalskyi, D.; Richman, J. D.; West, C. A.; Eisner, A. M.; Lockman, W. S.; Panduro Vazquez, W.; Schumm, B. A.; Seiden, A.; Chao, D. S.; Cheng, C. H.; Echenard, B.; Flood, K. T.; Hitlin, D. G.; Miyashita, T. S.; Ongmongkolkul, P.; Porter, F. C.; Röhrken, M.; Andreassen, R.; Huard, Z.; Meadows, B. T.; Pushpawela, B. G.; Sokoloff, M. D.; Sun, L.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Toki, W. H.; Spaan, B.; Bernard, D.; Verderi, M.; Playfer, S.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cibinetto, G.; Fioravanti, E.; Garzia, I.; Luppi, E.; Piemontese, L.; Santoro, V.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Martellotti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Contri, R.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Bhuyan, B.; Prasad, V.; Adametz, A.; Uwer, U.; Lacker, H. M.; Mallik, U.; Chen, C.; Cochran, J.; Prell, S.; Ahmed, H.; Gritsan, A. V.; Arnaud, N.; Davier, M.; Derkach, D.; Grosdidier, G.; Le Diberder, F.; Lutz, A. M.; Malaescu, B.; Roudeau, P.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Coleman, J. P.; Fry, J. R.; Gabathuler, E.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Di Lodovico, F.; Sacco, R.; Cowan, G.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Griessinger, K.; Hafner, A.; Schubert, K. R.; Barlow, R. J.; Lafferty, G. D.; Cenci, R.; Hamilton, B.; Jawahery, A.; Roberts, D. A.; Cowan, R.; Cheaib, R.; Patel, P. M.; Robertson, S. H.; Neri, N.; Palombo, F.; Cremaldi, L.; Godang, R.; Summers, D. J.; Simard, M.; Taras, P.; De Nardo, G.; Onorato, G.; Sciacca, C.; Raven, G.; Jessop, C. P.; LoSecco, J. M.; Honscheid, K.; Kass, R.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simi, G.; Simonetto, F.; Stroili, R.; Akar, S.; Ben-Haim, E.; Bomben, M.; Bonneaud, G. R.; Briand, H.; Calderini, G.; Chauveau, J.; Leruste, Ph.; Marchiori, G.; Ocariz, J.; Biasini, M.; Manoni, E.; Rossi, A.; Angelini, C.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Casarosa, G.; Chrzaszcz, M.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Oberhof, B.; Paoloni, E.; Rizzo, G.; Walsh, J. J.; Lopes Pegna, D.; Olsen, J.; Smith, A. J. S.; Anulli, F.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Pilloni, A.; Piredda, G.; Bünger, C.; Dittrich, S.; Grünberg, O.; Hess, M.; Leddig, T.; Voß, C.; Waldi, R.; Adye, T.; Olaiya, E. O.; Wilson, F. F.; Emery, S.; Vasseur, G.; Aston, D.; Bard, D. J.; Cartaro, C.; Convery, M. R.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Ebert, M.; Field, R. C.; Fulsom, B. G.; Graham, M. T.; Hast, C.; Innes, W. R.; Kim, P.; Leith, D. W. G. S.; Lindemann, D.; Luitz, S.; Luth, V.; Lynch, H. L.; MacFarlane, D. B.; Muller, D. R.; Neal, H.; Perl, M.; Pulliam, T.; Ratcliff, B. N.; Roodman, A.; Schindler, R. H.; Snyder, A.; Su, D.; Sullivan, M. K.; Va'vra, J.; Wisniewski, W. J.; Wulsin, H. W.; Purohit, M. V.; Wilson, J. R.; Randle-Conde, A.; Sekula, S. J.; Bellis, M.; Burchat, P. R.; Puccio, E. M. T.; Alam, M. S.; Ernst, J. A.; Gorodeisky, R.; Guttman, N.; Peimer, D. R.; Soffer, A.; Spanier, S. M.; Ritchie, J. L.; Schwitters, R. F.; Izen, J. M.; Lou, X. C.; Bianchi, F.; De Mori, F.; Filippi, A.; Gamba, D.; Lanceri, L.; Vitale, L.; Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.; Albert, J.; Banerjee, Sw.; Beaulieu, A.; Bernlochner, F. U.; Choi, H. H. F.; King, G. J.; Kowalewski, R.; Lewczuk, M. J.; Lueck, T.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Tasneem, N.; Gershon, T. J.; Harrison, P. F.; Latham, T. E.; Band, H. R.; Dasu, S.; Pan, Y.; Prepost, R.; Wu, S. L.; BaBar Collaboration

    2015-04-01

    A search is presented for the decay ϒ (1 S )→γ A0 , A0→c c ¯, where A0 is a candidate for the C P -odd Higgs boson of the next-to-minimal supersymmetric standard model. The search is based on data collected with the BABAR detector at the ϒ (2 S ) resonance. A sample of ϒ (1 S ) mesons is selected via the decay ϒ (2 S )→π+π-ϒ (1 S ) . The A0→c c ¯ decay is identified through the reconstruction of hadronic D0, D+, and D*(2010 )+ meson decays. No significant signal is observed. The measured 90% confidence-level upper limits on the product branching fraction B (ϒ (1 S )→γ A0)×B (A0→c c ¯ ) range from 7.4 ×10-5 to 2.4 ×10-3 for A0 masses from 4.00 to 8.95 GeV /c2 and 9.10 to 9.25 GeV /c2 , where the region between 8.95 and 9.10 GeV /c2 is excluded because of background from ϒ (2 S )→γ χb J(1 P ) , χb J(1 P )→γ ϒ (1 S ) decays.

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

    SciTech Connect

    Aubert, B

    2008-11-05

    We search for a light scalar particle produced in single-photon decays of the {Upsilon}(3S) resonance through the process {Upsilon}(3S) {yields} {gamma} + A{sup 0}, A{sup 0} {yields} invisible. Such an object appears in Next-to-Minimal Supersymmetric extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. If, in addition, there exists a light, stable neutralino, decays of A{sup 0} could be preferentially to an invisible final state. We search for events with a single high-energy photon and a large missing mass, consistent with a 2-body decay of {Upsilon}(3S). 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 {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} invisible) at (0.7-31) x 10{sup -6} in the mass range m{sub A{sup 0}} {le} 7.8 GeV. The results are preliminary.

  6. Search for a light Higgs resonance in radiative decays of the Y(1S) with a charm tag

    SciTech Connect

    Lees, J. P.

    2015-04-10

    In this study, a search is presented for the decay Υ(1S)→γA0, A0 → cc¯, where A0 is a candidate for the CP-odd Higgs boson of the next-to-minimal supersymmetric standard model. The search is based on data collected with the BABAR detector at the Υ(2S) resonance. A sample of Υ(1S) mesons is selected via the decay Υ(2S) → π+π Υ(1S). The A0 → cc¯ decay is identified through the reconstruction of hadronic D0, D+, and D*(2010)+ meson decays. No significant signal is observed. The measured 90% confidence-level upper limits on the product branching fraction B(Υ(1S) → γA0)×B(A0 → cc¯) range from 7.4×10–5 to 2.4×10–3 for A0 masses from 4.00 to 8.95 GeV/c2 and 9.10 to 9.25 GeV/c2, where the region between 8.95 and 9.10 GeV/c2 is excluded because of background from Υ(2S) → γχbJ(1P), χbJ(1P) → γΥ(1S) decays.

  7. Magnetic field effects on the Rabi splitting and radiative decay rates of the exciton-polariton states in a semiconductor microcavity

    NASA Astrophysics Data System (ADS)

    Fenniche, H.; Jaziri, S.; Bennaceur, R.

    1998-12-01

    We study theoretically a particular type of semiconductor microcavity formed by a quantum well embedded inside it and the distributed Bragg reflectors presenting a gradual structure. We apply to this structure a static magnetic field along the growth direction. In the strong coupling regime between the confined exciton and cavity modes, we evaluate the polariton Rabi splitting corresponding to the two lowest lying exciton states: HH1-CB1 and HH2-CB2 as a function of the applied magnetic field. In high magnetic field and for distinct reflectivities, we find that the Rabi splitting magnitude of the HH2-CB2 exciton is close to the fundamental one (HH1-CB1). In the presence of the magnetic field, the polariton Rabi splitting can be obtained even in low reflectivity. The dispersion polariton radiative decay rates related to the two lowest lying exciton states: HH1-CB1 and HH2-CB2 are calculated for different magnetic field values. At k //=0 and in the weak coupling regime, the polariton radiative decay rates are evaluated for both the HH1-CB1 and HH2-CB2 excitons. We show that for the fundamental excitonic state, the magnetic field value which determines the transition from the weak to the strong coupling regime is different from the HH2-CB2 exciton state.

  8. B{sup (*)}B{sup (*)} intermediate states contribution to {Upsilon}(4S,5S){yields}{eta}{sub b}+{gamma} radiative decay

    SciTech Connect

    Ke, Hong-Wei; Li, Xue-Qian; Liu, Xiang

    2010-09-01

    In this work, we investigate the rescattering effects in the radiative decay {Upsilon}(5S){yields}{eta}{sub b}+{gamma}, which were suggested to be crucially important for understanding the anomalous largeness of the branching ratios B({Upsilon}(5S){yields}{Upsilon}(1S)+{pi}{pi}) and B({Upsilon}(5S){yields}{Upsilon}(1S)+{eta}). Our calculations show that the rescattering effects may enhance {Gamma}({Upsilon}(10860){yields}{eta}{sub b}+{gamma}) by four orders, but the tetraquark structure does not. Recently the BABAR and CLEO collaborations have measured the mass of {eta}{sub b} and the branching ratios B({Upsilon}(2S){yields}{eta}{sub b}+{gamma}), B({Upsilon}(3S){yields}{eta}{sub b}+{gamma}). We hope that very soon, {Upsilon}(10860){yields}{eta}{sub b}+{gamma} will be measured and it would be an ideal opportunity for testing whether the rescattering or the tetraquark structure is responsible for the anomaly of B({Upsilon}(5S){yields}{Upsilon}(nS){pi}{sup +}{pi}{sup -}(n=1,2,3)), i.e., the future measurements on the radiative decays of {Upsilon}(5S) might be a touchstone of the two mechanisms.

  9. Measurements of Rn-222, Rn-220 and their decay products in the environmental air of the high background radiation areas in Yangjiang, China.

    PubMed

    Yuan, Y; Morishima, H; Shen, T; Koga, T; Wei, L; Sugahara, T

    2000-10-01

    For the renewal of dose estimation from internal irradiation in the high background radiation areas (HBRA) of Yangjiang, the measurements of radon, thoron and their decay products in the environmental air were conducted, including: (1) integrating measurements of Rn-222 and Rn-220 concentrations; (2) eqilibrium factor F for Rn-222 and alpha-potential energy value of Rn-220; (3) external gamma radiation in places where radon measurements were undertaken; (4) cumulative exposure to indoor radon for each family in a case-control study on lung cancer. The Rn-Tn cup monitor method was used for the integrating measurement of Rn-222 and Rn-220 concentration. An alpha track detector was used for the integration measurement of Rn-222 concentration in the case-control study on lung cancer. The results of measurements show that although the investigated areas are located between the Equator and the Tropic of Cancer, and that people live in well-ventilated dwellings, the concentrations of radon, especially of Rn-220 are significantly higher in the indoor air of HBRA than those in the control area. The value of equilibrium factors for Rn-222, the alpha potential energy of decay products from Rn-222 and Rn-220 are determined.

  10. Search for radiative penguin decays B(+)-->rho(+)gamma, B(0)-->rho(0)gamma, and B(0)-->omegagamma.

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Couderc, F; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Shelkov, V G; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Cuhadar-Donszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Foulkes, S D; Gary, J W; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; Macfarlane, D B; Paar, H P; Rahatlou, Sh; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Smith, J G; Zhang, J; Zhang, L; Chen, A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q L; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, K R; Schwierz, R; Spaan, B; Sundermann, J E; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Lavin, D; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Vetere, M Lo; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Biasini, M; Covarelli, R; Pioppi, M; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Laplace, S; Diberder, F Le; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Cormack, C M; Harrison, P F; Lodovico, F Di; Mohanty, G B; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; Losecco, J M; Allmendinger, T; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Buono, L Del; Hamon, O; John, M J J; Leruste, Ph; Malcles, J; Ocariz, J; Pivk, M; Roos, L; T'jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Miftakov, V; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Gioi, L Li; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Tehrani, F Safai; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; Groot, N De; Franek, B; Geddes, N I; Gopal, G P; Olaiya, E O; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; de Monchenault, G Hamel; Kozanecki, W; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yèche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Claus, R; Convery, M R; Cristinziani, M; Nardo, G De; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W; Elsen, E E; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Messner, R; Muller, D R; O'grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Va'vra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, P R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bona, M; Gallo, F; Gamba, D; Bosisio, L; Cartaro, C; Cossutti, F; Ricca, G Della; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R; Roney, J M; Sobie, R J; Band, H R; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mihalyi, A; Mohapatra, A K; Pan, Y; Prepost, R; Tan, P; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2005-01-14

    A search for the decays B-->rho(770)gamma and B0-->omega(782)gamma is performed on a sample of 211 x 10(6) Upsilon(4S)-->BB events collected by the BABAR detector at the SLAC PEP-II asymmetric-energy e(+)e(-) storage ring. No evidence for the decays is seen. We set the following limits on the individual branching fractions: B(B+-->rho(+)gamma)<1.8 x 10(-6), B(B0-->rho(0)gamma)<0.4 x 10(-6), and B(B0-->omegagamma)<1.0 x 10(-6) at the 90% confidence level. We use the quark model to limit the combined branching fraction B [B-->(rho/omega)gamma]<1.2 x 10(-6), from which we determine a constraint on the ratio of Cabibbo-Kobayashi-Maskawa matrix elements |V(td)|/|V(ts)|.

  11. Impact of radiation processing on quality during storage and post-refrigeration decay of plum (Prunus domestica L.) cv. Santaroza

    NASA Astrophysics Data System (ADS)

    Hussain, Peerzada R.; Dar, Mohd A.; Wani, Ali M.

    2013-04-01

    Gamma irradiation treatment was tested for maintaining storage quality and extending the shelf life of plum fruit. Matured green plums were irradiated in the dose range of 0.2-1.5 kGy and stored under ambient (temperature 25±2 °C, RH 70%) and refrigerated (temperature 3±1 °C, RH 80%) conditions. Studies revealed that irradiation treatment significantly (p≤0.05) maintained the storage quality of plum fruit under ambient as well as refrigerated conditions. Positive correlations (r=0.88) existed between the irradiation doses and firmness retention under both the storage conditions. In samples irradiated at 1.0 kGy, 1.2 kGy and 1.5 kGy, no microbial load was detected up to 8 and 12 days of ambient storage. Dose range of 1.2-1.5 kGy significantly inhibited the decaying of plums up to 16 days of ambient storage. Irradiation in combination with refrigeration prevented the decaying of plums up to 35 days as against the 12.5% decay in un-irradiated control samples. Irradiation dose of 1.2-1.5 kGy also gave an extension of 8 days during additional ambient storage of the plums at 25±2 °C, RH 70% following 35 days of refrigeration.

  12. Limits on the radiative decay of sterile neutrino dark matter from the unresolved cosmic and soft x-ray backgrounds

    NASA Astrophysics Data System (ADS)

    Abazajian, Kevork N.; Markevitch, Maxim; Koushiappas, Savvas M.; Hickox, Ryan C.

    2007-03-01

    We present upper limits on line emission in the Cosmic X-ray background (CXB) that would be produced by decay of sterile neutrino dark matter. We employ the spectra of the unresolved component of the CXB in the Chandra Deep Fields North and South obtained with the Chandra CCD detector in the E=0.8 9keV band. The expected decay flux comes from the dark matter on the lines of sight through the Milky Way galactic halo. Our constraints on the sterile neutrino decay rate are sensitive to the modeling of the Milky Way halo. The highest halo mass estimates provide a limit on the sterile neutrino mass of ms<2.9keV in the Dodelson-Widrow production model, while the lowest halo mass estimates provide the conservative limit of ms<5.7keV (2σ). We also discuss constraints from a short observation of the softer (E<1keV) X-ray background with a rocket-borne calorimeter by McCammon and collaborators.

  13. Search for X-Ray Induced Acceleration of the Decay of the 31-yr Isomer 178Hf Using Synchrotron Radiation

    SciTech Connect

    Ahmad, I; Banar, J C; Becker, J A; Gemmell, D S; Kraemer, A; Mashayekhi, A; McNabb, D P; Miller, G G; Moore, E F; Pangault, L N; Rundberg, R S; Schiffer, J P; Shastri, S D; Wang, T F; Wilhelmy, J B

    2002-05-09

    Releasing the energy stored in an isomeric nuclear state in a controlled way with an atomic or electromagnetic trigger is an attractive speculation: the energy gain may be on the order of the ratio of nuclear/atomic energies - MeV/keV. (Nuclear isomers are loosely defined as excited nuclear states with lifetimes longer than 10{sup -9} s.) Nuclear isomers, therefore, represent an opportunity for a stand-alone energy source if suitable schemes for trigger and control of the energy release can be found. Potential applications include space drive, as well as very bright {gamma}-ray sources. The nucleus {sup 178}Hf has a nuclear isomer with excitation energy E{sub x} = 2.447 MeV. The 2.447-MeV isomeric state decays slowly (t{sub 1/2} = 31 y) to the nearby state at 2.433 MeV. The J{sup {pi}} = 13{sup -} state loses energy in a rapid (t {approx} 10{sup -12} s) {gamma}-ray cascade ending at the 8{sup -} rotational band head which in turn decays via the ground-state rotational band cascade. The {gamma}-ray cascade is delayed at the 8{sup -} state at 1.147 MeV, since the 8{sup -} state is also isomeric, with t{sub 1/2} = 4 s. Very scarce quantities of the 16{sup +}, 31-yr isomer are available for research ({approx} 10{sup 15} atoms). Reports of triggered decay of the {sup 178}Hf isomer induced by x-rays delivered by a dental x-ray machine have been made [2,3]. Enhancements of {approx} 1 - 2% in the isomer decay rate (dN/dt = - (1 + {var_epsilon})N/{tau}) had been reported for various {gamma}-rays in the cascade (distinguished by red and vertical lines in Figure 1). The reported integrated cross section for triggering the decay is cm{sup 2} keV, so large as to demand new physics. We have sought to verify these reports taking advantage of the intense photon flux available at the Advanced Photon Source.

  14. Measurement of the Radiative Decay Rate and Energy of the Metastable (2s22p51=23s1=2)(J=0) Level in Fe XVII

    NASA Astrophysics Data System (ADS)

    Beiersdorfer, P.; Crespo López-Urrutia, J. R.; Träbert, E.

    2016-01-01

    Measurements at the Livermore electron beam ion trap have been performed in order to infer the energy and the radiative lifetime of the {(1{s}22{s}22{p}1/253{s}1/2)}J=0 level in the Fe xvii spectrum. This is the longest-lived level in the neonlike iron ion, and its radiative decay produces the Fe xvii line at 1153 Å, feeding the population of the {(1{s}22{s}22{p}3/253{s}1/2)}J=1 upper level of one of the most prominent lines in the Fe xvii L-shell X-ray spectrum, commonly dubbed 3G. In the presence of a strong (≥slant few kG) magnetic field, the {(1{s}22{s}22{p}1/253{s}1/2)}J=0 level has a finite probability to decay directly to the {(1{s}22{s}22{p}6)}J=0 neonlike ground level via the emission of an L-shell X-ray. Our measurements allow us to observe this X-ray line in the Fe xvii L-shell spectrum and from it to infer the radiative rate for the magnetic dipole decay of the {(1{s}22{s}22{p}1/253{s}1/2)}J=0 level to the {(1{s}22{s}22{p}3/253{s}1/2)}J=1. Our result of (1.45+/- 0.15)× {10}4 s-1 is in agreement with predictions. We have also measured the wavelength of the associated X-ray line to be 16.804 ± 0.002 Å, which means that the line is displaced 1.20 ± 0.05 eV from the neighboring {(2{s}22{p}1/253{s}1/2)}J=1\\to {(2{s}22{p}6)}J=0 transition, commonly labeled 3F. From our measurement, we infer 5950570 ± 710 cm-1 for the energy of the {(1{s}22{s}22{p}1/253{s}1/2)}J=0 level.

  15. The radiative leptonic decays D0 -> e+ e-γ ,μ ^+μ ^-γ in the standard model and beyond

    NASA Astrophysics Data System (ADS)

    Fajfer, S.; Singer, P.; Zupan, J.

    2003-03-01

    We present a calculation of the rare decay modes D^0 to e^+ e^- γ and D^0 to μ^+μ^- γ in the framework of the standard model. For the short distance part we have derived QCD corrections to the Wilson coefficients involved, including C9. The latter is found to be strongly suppressed by the corrections, leading to diminished values for the cto u l^+l^- branching ratios in the 10-10 range. Within SM the exclusive decays are dominated by long distance effects. Non-resonant contributions are estimated using heavy quark and chiral symmetries to be at the level of 10%, compared to the contributions arising from D^0to V γto l^+l^- γ, with V = ρ, ω, φ. The total SM branching ratio is predicted to be in the range (1-3)× 10^{-9}. We also consider contributions coming from MSSM with and without R parity conservation. The effects from MSSM are significant only for the R parity violating case. Such contributions enhance the branching ratio D^0 to μ^+μ^- γ to lesssim 0.5 × 10^{-7}, based on appropriately allowed values for C9 and C10. This selects D^0 to μ^+μ^- γ as a possible probe of new physics.

  16. Axions from wall decay

    SciTech Connect

    Chang, S; Hagmann, C; Sikivie, P

    2001-01-08

    The authors discuss the decay of axion walls bounded by strings and present numerical simulations of the decay process. In these simulations, the decay happens immediately, in a time scale of order the light travel time, and the average energy of the radiated axions is {approx_equal} 7m{sub a} for v{sub a}/m{sub a} {approx_equal} 500. is found to increase approximately linearly with ln(v{sub a}/m{sub a}). Extrapolation of this behavior yields {approx_equal} 60 m{sub a} in axion models of interest.

  17. Observation of h_{c} Radiative Decay h_{c}→γη^{'} and Evidence for h_{c}→γη.

    PubMed

    Ablikim, M; Achasov, M N; Ai, X C; Albayrak, O; Albrecht, M; Ambrose, D J; Amoroso, A; An, F F; An, Q; Bai, J Z; Baldini Ferroli, R; Ban, Y; Bennett, D W; Bennett, J V; Bertani, M; Bettoni, D; Bian, J M; Bianchi, F; Boger, E; Boyko, I; Briere, R A; Cai, H; Cai, X; Cakir, O; Calcaterra, A; Cao, G F; Cetin, S A; Chang, J F; Chelkov, G; Chen, G; Chen, H S; Chen, H Y; Chen, J C; Chen, M L; Chen, S; Chen, S J; Chen, X; Chen, X R; Chen, Y B; Cheng, H P; Chu, X K; Cibinetto, G; Dai, H L; Dai, J P; Dbeyssi, A; Dedovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, C; Dong, J; Dong, L Y; Dong, M Y; Dou, Z L; Du, S X; Duan, P F; Fan, J Z; Fang, J; Fang, S S; Fang, X; Fang, Y; Farinelli, R; Fava, L; Fedorov, O; Feldbauer, F; Felici, G; Feng, C Q; Fioravanti, E; Fritsch, M; Fu, C D; Gao, Q; Gao, X L; Gao, X Y; Gao, Y; Gao, Z; Garzia, I; Goetzen, K; Gong, L; Gong, W X; Gradl, W; Greco, M; Gu, M H; Gu, Y T; Guan, Y H; Guo, A Q; Guo, L B; Guo, R P; Guo, Y; Guo, Y P; Haddadi, Z; Hafner, A; Han, S; Hao, X Q; Harris, F A; He, K L; Held, T; Heng, Y K; Hou, Z L; Hu, C; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G S; Huang, J S; Huang, X T; Huang, X Z; Huang, Y; Huang, Z L; Hussain, T; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Jiang, L W; Jiang, X S; Jiang, X Y; Jiao, J B; Jiao, Z; Jin, D P; Jin, S; Johansson, T; Julin, A; Kalantar-Nayestanaki, N; Kang, X L; Kang, X S; Kavatsyuk, M; Ke, B C; Kiese, P; Kliemt, R; Kloss, B; Kolcu, O B; Kopf, B; Kornicer, M; Kupsc, A; Kühn, W; Lange, J S; Lara, M; Larin, P; Leng, C; Li, C; Li, Cheng; Li, D M; Li, F; Li, F Y; Li, G; Li, H B; Li, H J; Li, J C; Li, Jin; Li, K; Li, K; Li, Lei; Li, P R; Li, Q Y; Li, T; Li, W D; Li, W G; Li, X L; Li, X N; Li, X Q; Li, Y B; Li, Z B; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Lin, D X; Liu, B; Liu, B J; Liu, C X; Liu, D; Liu, F H; Liu, Fang; Liu, Feng; Liu, H B; Liu, H H; Liu, H H; Liu, H M; Liu, J; Liu, J B; Liu, J P; Liu, J Y; Liu, K; Liu, K Y; Liu, L D; Liu, P L; Liu, Q; Liu, S B; Liu, X; Liu, Y B; Liu, Z A; Liu, Zhiqing; Loehner, H; Lou, X C; Lu, H J; Lu, J G; Lu, Y; Lu, Y P; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lyu, X R; Ma, F C; Ma, H L; Ma, L L; Ma, M M; Ma, Q M; Ma, T; Ma, X N; Ma, X Y; Ma, Y M; Maas, F E; Maggiora, M; Mao, Y J; Mao, Z P; Marcello, S; Messchendorp, J G; Min, J; Mitchell, R E; Mo, X H; Mo, Y J; Morales Morales, C; Muchnoi, N Yu; Muramatsu, H; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, S L; Niu, X Y; Olsen, S L; Ouyang, Q; Pacetti, S; Pan, Y; Patteri, P; Pelizaeus, M; Peng, H P; Peters, K; Pettersson, J; Ping, J L; Ping, R G; Poling, R; Prasad, V; Qi, H R; Qi, M; Qian, S; Qiao, C F; Qin, L Q; Qin, N; Qin, X S; Qin, Z H; Qiu, J F; Rashid, K H; Redmer, C F; Ripka, M; Rong, G; Rosner, Ch; Ruan, X D; Sarantsev, A; Savrié, M; Schoenning, K; Schumann, S; Shan, W; Shao, M; Shen, C P; Shen, P X; Shen, X Y; Sheng, H Y; Shi, M; Song, W M; Song, X Y; Sosio, S; Spataro, S; Sun, G X; Sun, J F; Sun, S S; Sun, X H; Sun, Y J; Sun, Y Z; Sun, Z J; Sun, Z T; Tang, C J; Tang, X; Tapan, I; Thorndike, E H; Tiemens, M; Ullrich, M; Uman, I; Varner, G S; Wang, B; Wang, B L; Wang, D; Wang, D Y; Wang, K; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, S G; Wang, W; Wang, W P; Wang, X F; Wang, Y; Wang, Y D; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z H; Wang, Z Y; Wang, Z Y; Weber, T; Wei, D H; Wei, J B; Weidenkaff, P; Wen, S P; Wiedner, U; Wolke, M; Wu, L H; Wu, L J; Wu, Z; Xia, L; Xia, L G; Xia, Y; Xiao, D; Xiao, H; Xiao, Z J; Xie, Y G; Xiu, Q L; Xu, G F; Xu, J J; Xu, L; Xu, Q J; Xu, Q N; Xu, X P; Yan, L; Yan, W B; Yan, W C; Yan, Y H; Yang, H J; Yang, H X; Yang, L; Yang, Y X; Ye, M; Ye, M H; Yin, J H; Yu, B X; Yu, C X; Yu, J S; Yuan, C Z; Yuan, W L; Yuan, Y; Yuncu, A; Zafar, A A; Zallo, A; Zeng, Y; Zeng, Z; Zhang, B X; Zhang, B Y; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H H; Zhang, H Y; Zhang, J; Zhang, J J; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J Y; Zhang, J Z; Zhang, K; Zhang, L; Zhang, S Q; Zhang, X Y; Zhang, Y; Zhang, Y H; Zhang, Y N; Zhang, Y T; Zhang, Yu; Zhang, Z H; Zhang, Z P; Zhang, Z Y; Zhao, G; Zhao, J W; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, Q W; Zhao, S J; Zhao, T C; Zhao, Y B; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, W J; Zheng, Y H; Zhong, B; Zhou, L; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhu, K; Zhu, K J; Zhu, S; Zhu, S H; Zhu, X L; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, J; Zotti, L; Zou, B S; Zou, J H

    2016-06-24

    A search for radiative decays of the P-wave spin singlet charmonium resonance h_{c} is performed based on 4.48×10^{8} ψ^{'} events collected with the BESIII detector operating at the BEPCII storage ring. Events of the reaction channels h_{c}→γη^{'} and γη are observed with a statistical significance of 8.4σ and 4.0σ, respectively, for the first time. The branching fractions of h_{c}→γη^{'} and h_{c}→γη are measured to be B(h_{c}→γη^{'})=(1.52±0.27±0.29)×10^{-3} and B(h_{c}→γη)=(4.7±1.5±1.4)×10^{-4}, respectively, where the first errors are statistical and the second are systematic uncertainties. PMID:27391715

  18. Tooth Decay

    MedlinePlus

    ... in your mouth made up mostly of germs. Tooth decay starts in the outer layer, called the enamel. Without a filling, the decay can get deep into the tooth and its nerves and cause a toothache or ...

  19. Radiative transitions to an eta/sub c/(2980) candidate state and the observation of hadronic decays of this state

    SciTech Connect

    Bloom, E.D.

    1980-06-01

    Preliminary results from the Crystal Ball and Mark II experiments at SPEAR are presented on radiative transitions from psi'(3684) and J/psi(3095) to an eta/sub c/(2980) candidate state. In addition to the inclusive photon signals reported previously by the Crystal Ball, both detectors now see exclusive hadronic final state signals at masses consistent with the states inclusively determined mass of 2981 +- 16 MeV.

  20. Revisit the radiative decays of J/{psi} and {psi}{sup '}{yields}{gamma}{eta}{sub c}({gamma}{eta}{sub c}{sup '})

    SciTech Connect

    Li Gang; Zhao Qiang

    2011-10-01

    With the new measurements of J/{psi} and {psi}{sup '}{yields}{gamma}{eta}{sub c}({gamma}{eta}{sub c}{sup '}) from the CLEO and BES-III collaboration, we reinvestigate the intermediate meson loop (IML) contributions to these radiative decays in association with the quark model M1 transitions in an effective Lagrangian approach. It shows that the ''unquenched'' effects due to the intermediate hadron loops can be better quantified by the new data for J/{psi}{yields}{gamma}{eta}{sub c}. Although the IML contributions are relatively small in J/{psi}{yields}{gamma}{eta}{sub c}, they play a crucial role in {psi}{sup '}{yields}{gamma}{eta}{sub c}({gamma}{eta}{sub c}{sup '}). A prediction for the IML contributions to {psi}(3770){yields}{gamma}{eta}{sub c}({gamma}{eta}{sub c}{sup '}) is made. Such unquenched effects allow us to reach a coherent description of those three radiative transitions, and gain some insights into the underlying dynamics.

  1. Observation of the ηc (2980) Produced in the Radiative Decay of the ψ' (3684)

    SciTech Connect

    Himel, T. M.; Trilling, G. H.; Abrams, G. S.; Alam, M. S.; Blocker, C. A.; Blondel, A. P.; Boyarski, A. M.; Breidenbach, M.; Burke, D. L.; Carithers, W. C.; Chinowsky, W.; Coles, M. W.; Cooper, S.; Dieterle, W. E.; Dillon, J. B.; Dorenbosch, J.; Dorfan, J. M.; Eaton, M. W.; Feldman, G. J.; Franklin, M. E. B.; Gidal, G.; Goldhaber, G.; Hanson, G.; Hayes, K. G.; Hitlin, D. G.; Hollebeek, R. J.; Innes, W. R.; Jaros, J. A.; Jenni, P.; Johnson, A. D.; Kadyk, J. A.; Lankford, A. J.; Larsen, R. R.; Levi, M. E.; Lüth, V.; Millikan, R. E.; Nelson, M. E.; Pang, C. Y.; Patrick, J. F.; Perl, M. L.; Richter, B.; Roussarie, A.; Scharre, D. L.; Schindler, R. H.; Schwitters, R. F.; Siegrist, J. L.; Strait, J.; Taureg, H.; Tonutti, M.; Vella, E. N.; Vidal, R. A.; Videau, I.; Weiss, J. M.; Zaccone, H.

    1980-10-01

    In a study of {psi}'(3684) radiative decays with the Mark II detector at SPEAR, we observe the decay sequence {psi}' {yields} {gamma}{eta}{sub c}(2980), with the {eta}{sub c}(2980) decaying into several completely reconstructed hadronic modes. We obtain a mass M = 2980 ± 8 MeV / c{sup 2} and a width {Gamma} < 40 MeV / c{sup 2} (90% confidence level), and present estimates of some of the decay branching ratios.

  2. Measurement of Branching Fractions in Radiative BDecays to eta K gamma and Search for B Decays to eta' K gamma

    SciTech Connect

    Aubert, B.

    2006-03-31

    The authors present measurements of the B {yields} {eta}K{gamma} branching fractions and upper limits for the B {yields} {eta}'K{gamma} branching fractions. For B{sup +} {yields} {eta}K{sup +}{gamma} they also measure the time-integrated charge asymmetry. The data sample, collected with the BABAR detector at the Stanford Linear Accelerator Center, represents 232 x 10{sup 6} produced B{bar B} pairs. The results for branching fractions and upper limits at 90% C.L. in units of 10{sup -6} are: {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = 11.3{sub -2.6}{sup +2.8} {+-} 0.6, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = 10.0 {+-} 1.3 {+-} 0.5, {Beta}(B{sup 0} {yields} {eta}'K{sup 0}{gamma}) < 6.6, {Beta}(B{sup +} {yields} {eta}'K{sup +}{gamma}) < 4.2. The charge asymmetry in the decay B{sup +} {yields} {eta}K{sup +}{gamma} is {Alpha}{sub ch} = -0.09 {+-} 0.12 {+-} 0.01. The first errors are statistical and the second systematic.

  3. Decay of the excited state 32 P 3/2 of sodium atoms taking into account radiation trapping

    NASA Astrophysics Data System (ADS)

    Kosarev, N. I.

    2008-01-01

    The effective lifetime of the excited state 32 P 3/2 of sodium atoms corresponding to the transition with λ = 589 nm has been studied numerically. It is shown that the nonmonotonic behavior of the dependence of the Biberman-Holstein escape factor on the optical thickness of sodium vapor measured in the experiment (A. Romberg and H.-J. Kunze, J. Quant. Spectrosc. Radiat. Transfer 39 (2), 99 (1988)) should not be attributed to the manifestation of the effects of partial frequency redistribution.

  4. Conservation laws, radiative decay rates, and excited state localization in organometallic complexes with strong spin-orbit coupling.

    PubMed

    Powell, B J

    2015-01-01

    There is longstanding fundamental interest in 6-fold coordinated d(6) (t(2g)(6)) transition metal complexes such as [Ru(bpy)3](2+) and Ir(ppy)3, particularly their phosphorescence. This interest has increased with the growing realisation that many of these complexes have potential uses in applications including photovoltaics, imaging, sensing, and light-emitting diodes. In order to design new complexes with properties tailored for specific applications a detailed understanding of the low-energy excited states, particularly the lowest energy triplet state, T1, is required. Here we describe a model of pseudo-octahedral complexes based on a pseudo-angular momentum representation and show that the predictions of this model are in excellent agreement with experiment - even when the deviations from octahedral symmetry are large. This model gives a natural explanation of zero-field splitting of T1 and of the relative radiative rates of the three sublevels in terms of the conservation of time-reversal parity and total angular momentum modulo two. We show that the broad parameter regime consistent with the experimental data implies significant localization of the excited state. PMID:26123864

  5. Conservation laws, radiative decay rates, and excited state localization in organometallic complexes with strong spin-orbit coupling.

    PubMed

    Powell, B J

    2015-06-30

    There is longstanding fundamental interest in 6-fold coordinated d(6) (t(2g)(6)) transition metal complexes such as [Ru(bpy)3](2+) and Ir(ppy)3, particularly their phosphorescence. This interest has increased with the growing realisation that many of these complexes have potential uses in applications including photovoltaics, imaging, sensing, and light-emitting diodes. In order to design new complexes with properties tailored for specific applications a detailed understanding of the low-energy excited states, particularly the lowest energy triplet state, T1, is required. Here we describe a model of pseudo-octahedral complexes based on a pseudo-angular momentum representation and show that the predictions of this model are in excellent agreement with experiment - even when the deviations from octahedral symmetry are large. This model gives a natural explanation of zero-field splitting of T1 and of the relative radiative rates of the three sublevels in terms of the conservation of time-reversal parity and total angular momentum modulo two. We show that the broad parameter regime consistent with the experimental data implies significant localization of the excited state.

  6. First observation of radiative B{sup 0}{yields}{phi}K{sup 0}{gamma} decays and measurements of their time-dependent CP violation

    SciTech Connect

    Sahoo, H.; Browder, T. E.; Nishimura, K.; Vahsen, S. E.; Varner, G.; Adachi, I.; Haba, J.; Itoh, R.; Iwasaki, Y.; Nakao, M.; Nishida, S.; Nozaki, T.; Sakai, K.; Sakai, Y.; Sumisawa, K.; Trabelsi, K.; Uno, S.; Ushiroda, Y.; Asner, D. M.; Fast, J. E.

    2011-10-01

    We report the first observation of the radiative decay B{sup 0}{yields}{phi}K{sup 0}{gamma} using a data sample of 772x10{sup 6} BB pairs collected at the {Upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider. We observe a signal of 37{+-}8 events with a significance of 5.4 standard deviations including systematic uncertainties. The measured branching fraction is B(B{sup 0}{yields}{phi}K{sup 0}{gamma})=(2.74{+-}0.60{+-}0.32)x10{sup -6}, where the uncertainties are statistical and systematic, respectively. We also report the first measurements of time-dependent CP-violation parameters: S{sub {phi}}K{sub S}{sup 0}{sub {gamma}}=+0.74{sub -1.05}{sup +0.72}(stat){sub -0.24}{sup +0.10}(syst) and A{sub {phi}}K{sub S}{sup 0}{sub {gamma}}=+0.35{+-}0.58(stat){sub -0.10}{sup +0.23}(syst). Furthermore, we measure B(B{sup +}{yields}{phi}K{sup +}{gamma})=(2.48{+-}0.30{+-}0.24)x10{sup -6}, A{sub CP}=-0.03{+-}0.11{+-}0.08, and find that the signal is concentrated in the M{sub {phi}}K mass region near threshold.

  7. Penguin and rare decays in BABAR

    NASA Astrophysics Data System (ADS)

    Akar, Simon; Babar Collaboration

    2014-11-01

    We present recent results from the BABAR Collaboration on radiative decays. These include searches for new physics via measurements of several observables such as the time- dependent CP asymmetry in B0 → K0Sπ-π+γ exclusive decays, as well as direct CP asymmetries and branching fractions in B → Xsγ and B → Xsl+l- inclusive decays.

  8. Beauty baryon decays: a theoretical overview

    NASA Astrophysics Data System (ADS)

    Wang, Yu-Ming

    2014-11-01

    I overview the theoretical status and recent progress on the calculations of beauty baryon decays focusing on the QCD aspects of the exclusive semi-leptonic Λb → plμ decay at large recoil and theoretical challenges of radiative and electro-weak penguin decays Λb → Λγ,Λl+l-.

  9. Review of B and Bs decays

    NASA Astrophysics Data System (ADS)

    Bozzi, Concezio

    2014-05-01

    A review of B and Bs decays is presented. Emphasis is given to processes most sensitive to physics beyond the Standard Model, such as radiative, electroweak and "Higgs" penguin decays, and tree-level decays involving tau leptons in the final state. An outlook on future perspectives is also given.

  10. Radiative Penguin Decays at the BaBar Experiment B to K*gamma, B to rho gamma, B to omega gamma and B to X_s gamma

    SciTech Connect

    Grauges, E.

    2004-12-08

    A review of the results obtained from the analysis of the B meson decays that involve Radiative Penguin processes, recorded at the BaBar experiment at the Stanford Linear Accelerator Center PEP-II B-Factory, is presented. The physics interest of these processes and their SM prediction are discussed briefly. The most relevant selection techniques used in the analysis are described before quoting the latest results made public by the BaBar collaboration as of July 2003.

  11. Review of J//psi/ decays

    SciTech Connect

    Toki, W.H.

    1988-11-01

    Recent results from the Mark III collaboration in radiative J//psi/ decays are presented. This includes a study of iota/E decays in J//psi/ el/eta/ and elelp, two pseudoscalar decays near threshold in J//psi/ el and el /bar K/K and two vector decays in J//psi/ el /bar K//sup o/*K/sup o/*. 20 refs., 9 figs.

  12. Radioactive decay data tables

    SciTech Connect

    Kocher, D.C.

    1981-01-01

    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.

  13. Radiative decays X(3872){yields}{psi}(2S){gamma} and {psi}(4040){yields}X(3872){gamma} in effective field theory

    SciTech Connect

    Mehen, Thomas; Springer, Roxanne

    2011-05-01

    Heavy hadron chiral perturbation theory (HH{chi}PT) and XEFT are applied to the decays X(3872){yields}{psi}(2S){gamma} and {psi}(4040){yields}X(3872){gamma} under the assumption that the X(3872) is a molecular bound state of neutral charm mesons. In these decays the emitted photon energies are 181 MeV and 165 MeV, respectively, so HH{chi}PT can be used to calculate the underlying D{sup 0}D{sup 0*}+D{sup 0}D{sup 0*{yields}{psi}}(2S){gamma} or {psi}(4040){yields}(D{sup 0}D{sup 0*}+D{sup 0}D{sup 0*}){gamma} transition. These amplitudes are matched onto XEFT to obtain decay rates. The decays receive contributions from both long-distance and short-distance processes. We study the polarization of the {psi}(2S) in the decay X(3872){yields}{psi}(2S){gamma} and the angular distribution of X(3872) in the decay {psi}(4040){yields}X(3872){gamma} and find they can be used to differentiate between different decay mechanisms as well as discriminate between 2{sup -+} and 1{sup ++} quantum number assignments of the X(3872).

  14. Top decays in extended models

    SciTech Connect

    Gaitan, R.; Miranda, O. G.; Cabral-Rosetti, L. G.

    2009-04-20

    Top quark decays are interesting as a mean to test the Standard Model (SM) predictions. The Cabbibo-Kobayashi-Maskawa (CKM)-suppressed process t{yields}cWW, and the rare decays t{yields}cZ, t{yields}H{sup 0}+c, and t{yields}c{gamma} an excellent window to probe the predictions of theories beyond the SM. We evaluate the flavor changing neutral currents (FCNC) decay t{yields}H{sup 0}+c in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions; the FCNC decays may place at tree level and are only supressed by the mixing between ordinary top and charm quarks. We also comment on the decay process t{yields}c+{gamma}, which involves radiative corrections.

  15. Photoproduction and Decay of Light Mesons in CLAS

    SciTech Connect

    Amaryan, Moskov Jamalovich

    2013-08-01

    We present preliminary experimental results on photoproduction and decay of light mesons measured with CLAS setup at JLAB . This include Dalitz decay of pseudoscalar and vector mesons, radiative decay of pseudoscalar mesons as well hadronic decays of pseudoscalar and vector mesons. The collected high statistics in some of decay channels exceeds the world data by an order of magnitude and some other decay modes are observed for the first time. It is shown how the CLAS data will improve the world data on transition form factors of light mesons, Dalitz plot analyses, branching ratios of rare decay modes and other fundamental properties potentially accessible through the light meson decays.

  16. Radiation

    NASA Video Gallery

    Outside the protective cocoon of Earth's atmosphere, the universe is full of harmful radiation. Astronauts who live and work in space are exposed not only to ultraviolet rays but also to space radi...

  17. Experimental Status of b -> s(d) gamma Decays

    SciTech Connect

    Di Lodovico, F

    2004-02-05

    Radiative penguin decays provide an indirect probe for physics beyond the Standard Model and contribute to the determination of the CKM matrix elements. Copious quantities of B mesons produced at the B-Factories permit precision measurements of radiative penguin decays. We review the experimental status of the radiative penguin processes b {yields} s(d){gamma}.

  18. Seal Out Tooth Decay

    MedlinePlus

    ... Topics > Tooth Decay (Caries) > Seal Out Tooth Decay Seal Out Tooth Decay Main Content What are dental ... back teeth decay so easily? Who should get seal​ants? Should sealants be put on baby teeth? ...

  19. Search for x-ray induced acceleration of the decay of the 31-yr isomer of (178)Hf using synchrotron radiation.

    PubMed

    Ahmad, I; Banar, J C; Becker, J A; Gemmell, D S; Kraemer, A; Mashayekhi, A; McNabb, D P; Miller, G G; Moore, E F; Pangault, L N; Rundberg, R S; Schiffer, J P; Shastri, S D; Wang, T F; Wilhelmy, J B

    2001-08-13

    Enhanced decay of the 31-yr isomer of (178)Hf induced by x-ray irradiation has been reported previously. Here we describe an attempt to reproduce this result with an intense "white" x-ray beam from the Advanced Photon Source. No induced decay was observed. The upper limits for the energy-integrated cross sections for such a process, over the range of energies of 20--60 keV x rays, are less than 2 x 10(-27) cm(2) keV, below the previously reported values by more than 5 orders of magnitude; at 8 keV the limit is 5 x 10(-26) cm(2) keV.

  20. Effects of a decaying cosmological fluctuation.

    PubMed

    Amendola, Luca; Finelli, Fabio

    2005-06-10

    We present the initial conditions for a decaying cosmological perturbation and study its signatures in the cosmic microwave background anisotropies and matter power spectra. An adiabatic decaying mode in the presence of components that are not described as perfect fluids (such as collisionless matter) decays slower than in a perfect-fluid dominated Universe and displays super-Hubble oscillations. Wilkinson Microwave Anisotropy Probe first year data constrain the decaying to growing ratio of scale invariant adiabatic fluctuations at the matter-radiation equality to less than 10%.

  1. Observation of large-scale density cavities and parametric-decay instabilities in the high-altitude discrete auroral ionosphere under pulsed electromagnetic radiation.

    PubMed

    Wong, A Y; Chen, J; Lee, L C; Liu, L Y

    2009-03-13

    A large density cavity that measured 2000 km across and 500 km in height was observed by DEMETER and Formosat/COSMIC satellites in temporal and spatial relation to a new mode of propagation of electromagnetic (em) pulses between discrete magnetic field-aligned auroral plasmas to high altitudes. Recorded positive plasma potential from satellite probes is consistent with the expulsion of electrons in the creation of density cavities. High-frequency decay spectra support the concept of parametric instabilities fed by free energy sources. PMID:19392121

  2. An amplitude analyses of the K K-bar system (M < 2 GeV/C{sup 2}) produced in J/{Psi} radiative decay

    SciTech Connect

    Chen, Liang-Ping

    1991-11-01

    Using the 5.8 {times} 10{sup 6} J/{psi} events collected by the MARK 3 experiment on the SPEAR e{sup +}e{sup {minus}} storage ring at SLAC, a mass independent amplitude analysis of the J/{psi} {yields} {gamma} K{sub s}K{sub s} and J/{psi} {yields} K{sup +}K{sup {minus}} decays is presented. For K{bar K} systems having mass less than 2 GeV/c{sup 2}, the efficiency-corrected spherical harmonic moments of the J/{psi} joint decay angular distribution are measured. Fits are then performed in each independent mass interval in order to extract the underlying helicity amplitude structure; amplitudes describing K{bar K} systems of spin zero and spin two are included simultaneously. For the first time, a large spin zero component in the {theta}(1720) mass region is observed; consistent results are obtained for the data samples corresponding to the individual decay modes. This structure is attributed to the production of an S wave resonance, the f{sub 0}(1710), of mass and width M = 1710 {plus_minus} 10 MeV/c{sup 2}, {Gamma} = 186 {plus_minus} 30 MeV/c{sup 2}, respectively, with branching fraction Bf(J/{psi} {yields} {gamma}f{sub 0}, f{sub 0} {yields} K{bar K}) = (6.47 {plus_minus} 1.14 {plus_minus} 0.84) {times} 10{sup {minus}4}. A small amount ({approximately}24%) of spin two component in this mass region cannot be ruled out with the present statistics. These results revise the previous conclusion that the {theta}(1720) is a spin two resonance, a result obtained on the basis of spin hypothesis tests, which assumed that either pure spin zero or pure spin two states contribute in this mass region, but not both. The previous measurements of the f{sub 2}{prime} (1525) have been refined in the present analysis because of the simultaneous inclusion of spin zero and spin two amplitudes in the fit.

  3. An amplitude analyses of the K K-bar system (M < 2 GeV/C sup 2 ) produced in J/. Psi. radiative decay

    SciTech Connect

    Chen, Liang-Ping.

    1991-11-01

    Using the 5.8 {times} 10{sup 6} J/{psi} events collected by the MARK 3 experiment on the SPEAR e{sup +}e{sup {minus}} storage ring at SLAC, a mass independent amplitude analysis of the J/{psi} {yields} {gamma} K{sub s}K{sub s} and J/{psi} {yields} K{sup +}K{sup {minus}} decays is presented. For K{bar K} systems having mass less than 2 GeV/c{sup 2}, the efficiency-corrected spherical harmonic moments of the J/{psi} joint decay angular distribution are measured. Fits are then performed in each independent mass interval in order to extract the underlying helicity amplitude structure; amplitudes describing K{bar K} systems of spin zero and spin two are included simultaneously. For the first time, a large spin zero component in the {theta}(1720) mass region is observed; consistent results are obtained for the data samples corresponding to the individual decay modes. This structure is attributed to the production of an S wave resonance, the f{sub 0}(1710), of mass and width M = 1710 {plus minus} 10 MeV/c{sup 2}, {Gamma} = 186 {plus minus} 30 MeV/c{sup 2}, respectively, with branching fraction Bf(J/{psi} {yields} {gamma}f{sub 0}, f{sub 0} {yields} K{bar K}) = (6.47 {plus minus} 1.14 {plus minus} 0.84) {times} 10{sup {minus}4}. A small amount ({approximately}24%) of spin two component in this mass region cannot be ruled out with the present statistics. These results revise the previous conclusion that the {theta}(1720) is a spin two resonance, a result obtained on the basis of spin hypothesis tests, which assumed that either pure spin zero or pure spin two states contribute in this mass region, but not both. The previous measurements of the f{sub 2}{prime} (1525) have been refined in the present analysis because of the simultaneous inclusion of spin zero and spin two amplitudes in the fit.

  4. Resonant Auger decay driving intermolecular Coulombic decay in molecular dimers

    NASA Astrophysics Data System (ADS)

    Trinter, F.; Schöffler, M. S.; Kim, H.-K.; Sturm, F. P.; Cole, K.; Neumann, N.; Vredenborg, A.; Williams, J.; Bocharova, I.; Guillemin, R.; Simon, M.; Belkacem, A.; Landers, A. L.; Weber, Th.; Schmidt-Böcking, H.; Dörner, R.; Jahnke, T.

    2014-01-01

    In 1997, it was predicted that an electronically excited atom or molecule placed in a loosely bound chemical system (such as a hydrogen-bonded or van-der-Waals-bonded cluster) could efficiently decay by transferring its excess energy to a neighbouring species that would then emit a low-energy electron. This intermolecular Coulombic decay (ICD) process has since been shown to be a common phenomenon, raising questions about its role in DNA damage induced by ionizing radiation, in which low-energy electrons are known to play an important part. It was recently suggested that ICD can be triggered efficiently and site-selectively by resonantly core-exciting a target atom, which then transforms through Auger decay into an ionic species with sufficiently high excitation energy to permit ICD to occur. Here we show experimentally that resonant Auger decay can indeed trigger ICD in dimers of both molecular nitrogen and carbon monoxide. By using ion and electron momentum spectroscopy to measure simultaneously the charged species created in the resonant-Auger-driven ICD cascade, we find that ICD occurs in less time than the 20femtoseconds it would take for individual molecules to undergo dissociation. Our experimental confirmation of this process and its efficiency may trigger renewed efforts to develop resonant X-ray excitation schemes for more localized and targeted cancer radiation therapy.

  5. Measurement of the branching fractions of radiative leptonic τ decays τ → ℓγν anti-ν (ℓ=e,μ) at BABAR

    SciTech Connect

    Oberhof, Benjamin

    2015-04-29

    We perform a measurement of the branching fractions for τ → ℓγν anti ν, (ℓ = e, μ) decays for a minimum photon energy of 10 MeV in the τ rest frame using 430 fb-1 of e+e- collisions collected at the center-of-mass energy of the Υ(4S) resonance with the BABAR detector at the PEP-II storage rings. We find B(τ → μγνν) = (3.69±0.03±0.10)×103 and B(τ → eγνν) = (1.847 ± 0.015 ± 0.052) × 10-2 where the first quoted error is statistical and the second is systematic. These results represent a substantial improvement with respect to existing measurements for both channels.

  6. Evidence for Orbital Decay of RX J1914.4+2456: Gravitational Radiation and the Nature of the X-Ray Emission

    NASA Technical Reports Server (NTRS)

    Strohmayer, Tod E.; White, Nicholas E. (Technical Monitor)

    2002-01-01

    RX J1914.4+2456 is a candidate double-degenerate binary (AM CVn) with a putative 569 s orbital period. If this identification is correct, then it has one of the shortest binary orbital periods known, and gravitational radiation should drive the orbital evolution and mass transfer if the binary is semi-detached. Here we report the results of a coherent timing study of the archival ROSAT data for RX J1914.4+2456. We performed a phase coherent timing analysis using all five ROSAT observations spanning a four-year period. We demonstrate that all the data can be phase connected, and we show that the 1.756 mHz orbital frequency is increasing at a rate of 1.5 +/- 0.4 x 10(exp -17) Hz/s consistent with the expected loss of angular momentum from the binary system via gravitational radiation. In addition to providing evidence for the emission of gravitational waves, our measurement of the orbital v(dot) constrains models for the X-ray emission and the nature of the secondary. If stable mass accretion drives the X-ray flux, then a positive v(dot) is inconsistent with a degenerate donor. A helium burning dwarf is compatible if indeed such systems can have periods as short as that of RX J1914.4+2456, an open theoretical question. Our measurement of a positive v(dot) is consistent with the unipolar induction model of Wu et al. which does not require accretion to drive the X-ray flux. We discuss how future timing measurements of RX J1914.4+2456 (and systems like it) with for example, Chandra and XMM-Newton, can provide a unique probe of the interaction between mass loss and gravitational radiation. We also discuss the importance of such measurements in the context of gravitational wave detection from space, such as is expected in the future with the LISA mission.

  7. Searching the Inclusive Lepton + Photon + Missing E(T) + b-quark Signature for Radiative Top Quark Decay and Non-Standard-Model Processes

    SciTech Connect

    Aaltonen, T.; Adelman, Jahred A.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E.; Anastassov, A.; Annovi, Alberto; Antos, Jaroslav; Apollinari, G.; Apresyan, A.; /Purdue U. /Waseda U.

    2009-06-01

    In a search for new phenomena in a signature suppressed in the standard model of elementary particles (SM), we compare the inclusive production of events containing a lepton ({ell}), a photon ({gamma}), significant transverse momentum imbalance (E{sub T}), and a jet identified as containing a b-quark, to SM predictions. The search uses data produced in proton-antiproton collisions at {radical}s = 1.96 TeV corresponding to 1.9 fb{sup -1} of integrated luminosity taken with the CDF detector at the Fermilab Tevatron. We find 28 {ell}{gamma}bE{sub T} events versus an expectation of 31.0{sub -3.5}{sup +4.1} events. If we further require events to contain at least three jets and large total transverse energy, simulations predict that the largest SM source is top-quark pair production with an additional radiated photon, t{bar t} + {gamma}. In the data we observe 16 t{bar t}{gamma} candidate events versus an expectation from non-top-quark SM sources of 11.2{sub -2.1}{sup +2.3}. Assuming the difference between the observed number and the predicted non-top-quark total is due to SM top quark production, we estimate the t{bar t} cross section to be 0.15 {+-} 0.08 pb.

  8. Interatomic Coulombic decay in nanodroplets

    NASA Astrophysics Data System (ADS)

    Sisourat, Nicolas

    2014-05-01

    Interatomic (molecular) Coulombic decay (ICD) is an ultrafast non-radiative electronic decay process for excited atoms or molecules embedded in a chemical environment. Via ICD, the excited system can get rid of the excess energy, which is transferred to one of the neighbors and ionize it. ICD produces two charged particles next to each other and thus leads to Coulomb explosion. Kinetic energy distribution of the ionic fragments gives information on the dynamics of the decay process. From the theoretical point of view general quantum mechanical equations for describing the decay processes and the subsequent fragmentations are known but are only applicable for rather small systems. During the presentation, a semiclassical approach for modeling ICD and the subsequent fragmentations will be presented. This approach involves a classical treatment for the nuclear motion while retaining a quantum description for the electron dynamics. Such approach has low computational costs and can be used to study much larger systems. Comparison of the results from semiclassical and from quantum mechanical calculations will be shown for simple systems, demonstrating the good performance of the semiclassical method. Results on ICD in nanodroplets will finally be reported.

  9. Evidence for the decay

    NASA Astrophysics Data System (ADS)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Callot, O.; Calvi, M.; Gomez, M. Calvo; Camboni, A.; Campana, P.; Perez, D. Campora; Caponio, F.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Akiba, K. Carvalho; Casse, G.; Cassina, L.; Garcia, L. Castillo; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Vidal, X. Cid; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Counts, I.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Torres, M. Cruz; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Suárez, A. Dosil; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Esen, S.; Falabella, A.; Färber, C.; Farinelli, C.; Farley, N.; Farry, S.; Ferguson, D.; Albor, V. Fernandez; Rodrigues, F. Ferreira; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Torreira, A. Gallas; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Tico, J. Garra; Garrido, L.; Gaspar, C.; Gauld, R.; Gavardi, L.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Giani', S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Gotti, C.; Gándara, M. Grabalosa; Diaz, R. Graciani; Cardoso, L. A. Granado; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Hafkenscheid, T. W.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Morata, J. A. Hernando; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hunt, P.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jans, E.; Jaton, P.; Jawahery, A.; Jezabek, M.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Kelsey, M.; Kenyon, I. R.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lopez-March, N.; Lowdon, P.; Lu, H.; Lucchesi, D.; Luo, H.; Luppi, E.; Lupton, O.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Malde, S.; Manca, G.; Mancinelli, G.; Manzali, M.; Maratas, J.; Marchand, J. F.; Marconi, U.; Benito, C. Marin; Marino, P.; Märki, R.; Marks, J.; Martellotti, G.; Martens, A.; Sánchez, A. Martín; Martinelli, M.; Santos, D. Martinez; Vidal, F. Martinez; Tostes, D. Martins; Massafferri, A.; Matev, R.; Mathe, Z.; Matteuzzi, C.; Mazurov, A.; McCann, M.; McCarthy, J.; McNab, A.; McNulty, R.; McSkelly, B.; Meadows, B.; Meier, F.; Meissner, M.; Merk, M.; Milanes, D. A.; Minard, M.-N.; Rodriguez, J. Molina; Monteil, S.; Moran, D.; Morandin, M.; Morawski, P.; Mordà, A.; Morello, M. J.; Moron, J.; Mountain, R.; Muheim, F.; Müller, K.; Muresan, R.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nasteva, I.; Needham, M.; Neri, N.; Neubert, S.; Neufeld, N.; Neuner, M.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Nicol, M.; Niess, V.; Niet, R.; Nikitin, N.; Nikodem, T.; Novoselov, A.; Oblakowska-Mucha, A.; Obraztsov, V.; Oggero, S.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Onderwater, G.; Orlandea, M.; Goicochea, J. M. Otalora; Owen, P.; Oyanguren, A.; Pal, B. K.; Palano, A.; Palombo, F.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Pappalardo, L.; Parkes, C.; Parkinson, C. J.; Passaleva, G.; Patel, G. D.; Patel, M.; Patrignani, C.; Alvarez, A. Pazos; Pearce, A.; Pellegrino, A.; Altarelli, M. Pepe; Perazzini, S.; Trigo, E. Perez; Perret, P.; Perrin-Terrin, M.; Pescatore, L.; Pesen, E.; Petridis, K.; Petrolini, A.; Olloqui, E. Picatoste; Pietrzyk, B.; Pilař, T.; Pinci, D.; Pistone, A.; Playfer, S.; Casasus, M. Plo; Polci, F.; Poluektov, A.; Polycarpo, E.; Popov, A.; Popov, D.; Popovici, B.; Potterat, C.; Powell, A.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Navarro, A. Puig; Punzi, G.; Qian, W.; Rachwal, B.; Rademacker, J. H.; Rakotomiaramanana, B.; Rama, M.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Reichert, S.; Reid, M. M.; dos Reis, A. C.; Ricciardi, S.; Richards, A.; Rinnert, K.; Molina, V. Rives; Romero, D. A. Roa; Robbe, P.; Roberts, D. A.; Rodrigues, A. B.; Rodrigues, E.; Perez, P. Rodriguez; Roiser, S.; Romanovsky, V.; Vidal, A. Romero; Rotondo, M.; Rouvinet, J.; Ruf, T.; Ruffini, F.; Ruiz, H.; Valls, P. Ruiz; Sabatino, G.; Silva, J. J. Saborido; Sagidova, N.; Sail, P.; Saitta, B.; Guimaraes, V. Salustino; Sedes, B. Sanmartin; Santacesaria, R.; Rios, C. Santamarina; Santovetti, E.; Sapunov, M.; Sarti, A.; Satriano, C.; Satta, A.; Savrie, M.; Savrina, D.; Schiller, M.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmidt, B.; Schneider, O.; Schopper, A.; Schune, M.-H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Seco, M.; Semennikov, A.; Senderowska, K.; Sepp, I.; Serra, N.; Serrano, J.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, O.; Shevchenko, V.; Shires, A.; Sidorov, F.; Coutinho, R. Silva; Simi, G.; Sirendi, M.; Skidmore, N.; Skwarnicki, T.; Smith, N. A.; Smith, E.; Smith, E.; Smith, J.; Smith, M.; Snoek, H.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; Souza, D.; De Paula, B. Souza; Spaan, B.; Sparkes, A.; Spinella, F.; Spradlin, P.; Stagni, F.; Stahl, S.; Steinkamp, O.; Stevenson, S.; Stoica, S.; Stone, S.; Storaci, B.; Stracka, S.; Straticiuc, M.; Straumann, U.; Stroili, R.; Subbiah, V. K.; Sun, L.; Sutcliffe, W.; Swientek, K.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szczypka, P.; Szilard, D.; Szumlak, T.; T'Jampens, S.; Teklishyn, M.; Tellarini, G.; Teubert, F.; Thomas, C.; Thomas, E.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Tolk, S.; Tomassetti, L.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Tran, M. T.; Tresch, M.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Garcia, M. Ubeda; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vagnoni, V.; Valenti, G.; Vallier, A.; Gomez, R. Vazquez; Regueiro, P. Vazquez; Sierra, C. Vázquez; Vecchi, S.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; Voss, H.; de Vries, J. A.; Waldi, R.; Wallace, C.; Wallace, R.; Wandernoth, S.; Wang, J.; Ward, D. R.; Watson, N. K.; Websdale, D.; Whitehead, M.; Wicht, J.; Wiedner, D.; Wilkinson, G.; Williams, M. P.; Williams, M.; Wilson, F. F.; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wright, S.; Wu, S.; Wyllie, K.; Xie, Y.; Xing, Z.; Yang, Z.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, F.; Zhang, L.; Zhang, W. C.; Zhang, Y.; Zhelezov, A.; Zhokhov, A.; Zhong, L.; Zvyagin, A.

    2014-05-01

    Evidence is presented for the decay using proton-proton collision data, corresponding to an integrated luminosity of 3 fb-1, collected with the LHCb detector. A signal yield of 32 ± 8 decays is found with a significance of 4.5 standard deviations. The ratio of the branching fraction of the decay to that of the decay is measured to be where the first uncertainty is statistical and the second is systematic. [Figure not available: see fulltext.

  10. Analytical properties of the plasmon decay profile in a periodic metal-nanoparticle chain.

    PubMed

    Fung, Kin Hung; Tang, Ross Chin Hang; Chan, C T

    2011-06-15

    We show that the spatial decay of plasmons in a periodic metal-nanoparticle chain is composed of exponential and power-law decays. Our results show a high level of similarity between the absorptive and radiative decay channels. By analyzing the poles (and the corresponding residues) of the generating function for the lattice Green's function, we explain the details of the spatial decay profile. We also present an analytical formula for the decay profile.

  11. Cascade decays of hollow ions

    SciTech Connect

    Omar, G. ); Hahn, Y. )

    1991-05-01

    A multiple-electron-emission process for atoms with one or more inner-shell vacancies is treated using the radiative- and Auger-electron-emission cascade model, in which inner-shell holes are assumed to decay by sequentially emitting radiations and/or Auger electrons. Such hollow ions are produced by synchrotron irradiation of atomic targets and in ion-surface interactions with multiple-electron transfers. The final charge-state distribution is determined by the Auger and radiative branching ratios at each stage of the decay sequence. At intermediate stages of cascade, hollow ions with more than one hole in different ionization stages are created. The Ne, Mg, and Fe{sup 14+} ions with the initial 1{ital s}, 2{ital s}, and 2{ital p} vacancies are considered in detail, and the core charge dependence of the maximum charge state is studied. The hollow Mg ion with double initial 1{ital s} holes is analyzed, and the result compared with that for the case of one 1{ital s} hole. The peak is shifted more than two units to a higher degree of ionization. The correlated shake-off and shake-up multiple-electron processes are not considered, but they are expected to cause further shifts.

  12. The program RADLST (Radiation Listing)

    SciTech Connect

    Burrows, T.W.

    1988-02-29

    The program RADLST (Radiation Listing) is designed to calculate the nuclear and atomic radiations associated with the radioactive decay of nuclei. It uses as its primary input nuclear decay data in the Evaluated Nuclear Structure Data File (ENSDF) format. The code is written in FORTRAN 77 and, with a few exceptions, is consistent with the ANSI standard. 65 refs.

  13. Bremsstrahlung in {alpha} Decay Reexamined

    SciTech Connect

    Boie, H.; Scheit, H.; Jentschura, U. D.; Koeck, F.; Lauer, M.; Schwalm, D.; Milstein, A. I.; Terekhov, I. S.

    2007-07-13

    A high-statistics measurement of bremsstrahlung emitted in the {alpha} decay of {sup 210}Po has been performed, which allows us to follow the photon spectra up to energies of {approx}500 keV. The measured differential emission probability is in good agreement with our theoretical results obtained within the quasiclassical approximation as well as with the exact quantum mechanical calculation. It is shown that, due to the small effective electric dipole charge of the radiating system, a significant interference between the electric dipole and quadrupole contributions occurs, which is altering substantially the angular correlation between the {alpha} particle and the emitted photon.

  14. Bremsstrahlung in alpha decay reexamined.

    PubMed

    Boie, H; Scheit, H; Jentschura, U D; Köck, F; Lauer, M; Milstein, A I; Terekhov, I S; Schwalm, D

    2007-07-13

    A high-statistics measurement of bremsstrahlung emitted in the alpha decay of (210)Po has been performed, which allows us to follow the photon spectra up to energies of approximately 500 keV. The measured differential emission probability is in good agreement with our theoretical results obtained within the quasiclassical approximation as well as with the exact quantum mechanical calculation. It is shown that, due to the small effective electric dipole charge of the radiating system, a significant interference between the electric dipole and quadrupole contributions occurs, which is altering substantially the angular correlation between the alpha particle and the emitted photon.

  15. Detection of radon decay products in rainwater.

    PubMed

    Baker, S I

    1999-11-01

    The Argonne National Laboratory-East (ANL-E) Environmental Radiation Monitoring System measures and records ambient radiation levels and provides detection capability for radon decay products in rain clouds. These decay products in rainwater tracked into a facility on the shoes of workers can cause false alarms from hand and shoe monitors. The monitors at ANL-E can easily detect the radon decay products, and the 19.6 and 26.8 min half-lives of the beta-particle emitters are long enough in many cases for sufficient activity to still be present to initiate a contamination alarm when the shoes are checked for radioactivity. The Environmental Radiation Monitoring System provides a warning when precipitation contains elevated levels of radon decay products. It is based on a prototype developed at the Super Collider Laboratory. During its first year of operation there were nine alarms from radon decay products with an alarm trigger point set at 30% greater than background. The alarms occurred at both monitoring stations, which are approximately 1,000 m apart, indicating large diameter radon clouds. The increases in background were associated with low atmospheric pressure. There was no correlation with radon released from the coal-burning steam plant on the site. Alarms also occurred when short-lived accelerator-produced radioactivity in the exhaust stack plume passed over the NaI(Tl) detector in one of the stations. The 450 MeV proton accelerator near the station produced 12C, 13N, and 15O by spallation of air nuclei. The gamma-ray spectrum from the plume from the accelerator exhaust stack was dominated by the 511 keV annihilation gamma rays from decay of these radionuclides. These gamma rays were easily distinguished from the 609 keV, 1,120 keV, and 1,764 keV gamma rays emitted by the radon decay products.

  16. Thermal effects and sudden decay approximation in the curvaton scenario

    SciTech Connect

    Kitajima, Naoya; Takesako, Tomohiro; Yokoyama, Shuichiro; Langlois, David; Takahashi, Tomo E-mail: langlois@apc.univ-paris7.fr E-mail: takesako@icrr.u-tokyo.ac.jp

    2014-10-01

    We study the impact of a temperature-dependent curvaton decay rate on the primordial curvature perturbation generated in the curvaton scenario. Using the familiar sudden decay approximation, we obtain an analytical expression for the curvature perturbation after the decay of the curvaton. We then investigate numerically the evolution of the background and of the perturbations during the decay. We first show that the instantaneous transfer coefficient, related to the curvaton energy fraction at the decay, can be extended into a more general parameter, which depends on the net transfer of the curvaton energy into radiation energy or, equivalently, on the total entropy ratio after the complete curvaton decay. We then compute the curvature perturbation and compare this result with the sudden decay approximation prediction.

  17. Rare Decays at LHCb

    NASA Astrophysics Data System (ADS)

    Hall, Sam

    2014-04-01

    Rare decays of beauty and charm hadrons provide an effective method of testing the Standard Model and probing possible new physics scenarios. The LHCb experiment has published a variety of interesting results in this field, some of which are presented here. In particular the measurements of the branching fractions of B(s)0 → μ+μ- which, in combination with CMS, resulted in the first observation of the Bs0 → μ+μ- decay. Other topics include searches for the rare decay D0 → μ+μ-, the lepton flavour violating decays B(s)0 → e±μ∓, and the observation of the ψ(4160) resonance in the region of low recoil in B+ → K+μ+μ- decay. New results on the angular analysis of the decay B0 → K*0μ+μ- with form factor independent observables are also shown.

  18. Effective Majorana neutrino decay

    NASA Astrophysics Data System (ADS)

    Duarte, Lucía; Romero, Ismael; Peressutti, Javier; Sampayo, Oscar A.

    2016-08-01

    We study the decay of heavy sterile Majorana neutrinos according to the interactions obtained from an effective general theory. We describe the two- and three-body decays for a wide range of neutrino masses. The results obtained and presented in this work could be useful for the study of the production and detection of these particles in a variety of high energy physics experiments and astrophysical observations. We show in different figures the dominant branching ratios and the total decay width.

  19. RARE DECAYS INCLUDING PENGUINS

    SciTech Connect

    Eigen, G

    2003-12-04

    The authors present a preliminary measurement of the exclusive charmless semileptonic B decays, B {yields} {rho}{ell}{nu}, and the extraction of the CKM parameters V{sub ub}. IN a data sample of 55 x 10{sup 6} B{bar B} events they measure a branching fraction of {Beta}(B {yields} {rho}{ell}{nu}) = (3.39 {+-} 0.44{sub stat} {+-} 0.52{sub sys} {+-} 0.60{sub th}) x 10{sup -4} yielding |V{sub ub}| = (3.69 {+-} 0.23{sub stat} {+-} 0.27{sub sys -0.59th}{sup +0.40}) x 10{sup -3}. Next, they report on a preliminary study of the radiative penguin modes B {yields} K{ell}{sup +}{ell}{sup -} and B {yields} K*{ell}{sup +}{ell}{sup -}. In a data sample of 84 x 10{sup 6} B{bar B} events they observe a significant signal (4.4{sigma}) in B {yields} K{ell}{sup +}{ell}{sup -}, yielding a branching fraction of {Beta}(B {yields} K{ell}{sup +}{ell}{sup -}) = (0.78{sub -0.20-0.18}{sup +0.24+0.11}) x 10{sup -6}. In B {yields} K*{ell}{sup +}{ell}{sup -} the observed yield is not yet significant (2.8{sigma}), yielding an upper limit of the branching fraction of {Beta}(B {yields} K*{ell}{sup +}{ell}{sup -}) 3.0 x 10{sup -6} {at} 90% confidence level. Finally, they summarize preliminary results of searches for B {yields} {rho}({omega}){gamma}, B{sup +} {yields} K{sup +} {nu}{bar {nu}} and B{sup 0} {yields} {ell}{sup +}{ell}{sup -}.

  20. Re-ionization and decaying dark matter

    NASA Technical Reports Server (NTRS)

    Dodelson, Scott; Jubas, Jay M.

    1991-01-01

    Gunn-Peterson tests suggest that the Universe was reionized after the standard recombination epoch. A systematic treatment is presented of the ionization process by deriving the Boltzmann equations appropriate to this regime. A compact solution for the photon spectrum is found in terms of the ionization ratio. These equations are then solved numerically for the Decaying Dark Matter scenario, wherein neutrinos with mass of order 30 eV radiatively decay producing photons which ionize the intergalactic medium. It was found that the neutrino mass and lifetime are severely constrained by Gunn-Peterson tests, observations of the diffuse photon spectrum in the ultraviolet regime, and the Hubble parameter.

  1. Tuning fork decay.

    PubMed

    Miller, G W

    1979-03-01

    Tuning fork tests are used routinely by many otologists. A different group of otologists find the tests inconsistent and unreliable. This controversy has probably developed because the audiometer has replaced the tuning fork in hearing measurement. As a result, the art of use of the tuning fork is poorly learned. This study examines decay, one of the physical parameters of tuning forks. Measurements of acoustic (sound wave) and vibration (stem movement) decay were made. Alteration in decay due to pressure changes on the fork stem were studied. Acoustic signals were generated in an anechoic chamber. Vibration measurements were obtained using an artificial mastoid. Analysis of the signals was accomplished by a system of amplifiers, filters, tape recorders, and a graphic recorder. Tuning fork sound decay is a property of the instrument which occurs every time the fork is struck. The decay is a constant in decibels per second. The acoustic mode and the vibration mode decay at similar rates for the same fork. The strike frequency (a higher frequency than the fundamental produced when the fork is struck) also has a constant decay rate in decibels per second, and it is reported here for the first time. Force of 800 gm. and less applied to the bottom of the stem in vibration measurement caused minimal decay constant changes. When the physical parameters of the tuning fork (including this information on damping) are fully studied, tuning fork testing should become more of a science and less of an art.

  2. Radioactive Decay - An Analog.

    ERIC Educational Resources Information Center

    McGeachy, Frank

    1988-01-01

    Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

  3. Majorana neutrino masses from neutrinoless double-beta decays and lepton-number-violating meson decays

    NASA Astrophysics Data System (ADS)

    Liu, Jun-Hao; Zhang, Jue; Zhou, Shun

    2016-09-01

    The Schechter-Valle theorem states that a positive observation of neutrinoless double-beta (0 νββ) decays implies a finite Majorana mass term for neutrinos when any unlikely fine-tuning or cancellation is absent. In this note, we reexamine the quantitative impact of the Schechter-Valle theorem, and find that current experimental lower limits on the half-lives of 0 νββ-decaying nuclei have placed a restrictive upper bound on the Majorana neutrino mass | δ mνee | < 7.43 ×10-29 eV radiatively generated at the four-loop level. Furthermore, we generalize this quantitative analysis of 0 νββ decays to that of the lepton-number-violating (LNV) meson decays M- →M‧+ + ℓα- + ℓβ- (for α , β = e or μ). Given the present upper limits on these rare LNV decays, we have derived the loop-induced Majorana neutrino masses | δ mνee | < 9.7 ×10-18 eV, | δ mνeμ | < 1.6 ×10-15 eV and | δ mνμμ | < 1.0 ×10-12 eV from K- →π+ +e- +e-, K- →π+ +e- +μ- and K- →π+ +μ- +μ-, respectively. A partial list of radiative neutrino masses from the LNV decays of D, Ds and B mesons is also given.

  4. Hypernuclear Weak Decays

    NASA Astrophysics Data System (ADS)

    Itonaga, K.; Motoba, T.

    The recent theoretical studies of Lambda-hypernuclear weak decaysof the nonmesonic and pi-mesonic ones are developed with the aim to disclose the link between the experimental decay observables and the underlying basic weak decay interactions and the weak decay mechanisms. The expressions of the nonmesonic decay rates Gamma_{nm} and the decay asymmetry parameter alpha_1 of protons from the polarized hypernuclei are presented in the shell model framework. We then introduce the meson theoretical Lambda N -> NN interactions which include the one-meson exchanges, the correlated-2pi exchanges, and the chiral-pair-meson exchanges. The features of meson exchange potentials and their roles on the nonmesonic decays are discussed. With the adoption of the pi + 2pi/rho + 2pi/sigma + omega + K + rhopi/a_1 + sigmapi/a_1 exchange potentials, we have carried out the systematic calculations of the nonmesonic decay observables for light-to-heavy hypernuclei. The present model can account for the available experimental data of the decay rates, Gamma_n/Gamma_p ratios, and the intrinsic asymmetry parameters alpha_Lambda (alpha_Lambda is related to alpha_1) of emitted protons well and consistently within the error bars. The hypernuclear lifetimes are evaluated by converting the total weak decay rates Gamma_{tot} = Gamma_pi + Gamma_{nm} to tau, which exhibit saturation property for the hypernuclear mass A ≥ 30 and agree grossly well with experimental data for the mass range from light to heavy hypernuclei except for the very light ones. Future extensions of the model and the remaining problems are also mentioned. The pi-mesonic weak processes are briefly surveyed, and the calculations and predictions are compared and confirmed by the recent high precision FINUDA pi-mesonic decay data. This shows that the theoretical basis seems to be firmly grounded.

  5. Factorization in B ---> V gamma decays

    SciTech Connect

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

    2005-03-01

    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.

  6. Modulated curvaton decay

    SciTech Connect

    Assadullahi, Hooshyar; Wands, David; Firouzjahi, Hassan; Namjoo, Mohammad Hossein E-mail: firouz@mail.ipm.ir E-mail: david.wands@port.ac.uk

    2013-03-01

    We study primordial density perturbations generated by the late decay of a curvaton field whose decay rate may be modulated by the local value of another isocurvature field, analogous to models of modulated reheating at the end of inflation. We calculate the primordial density perturbation and its local-type non-Gaussianity using the sudden-decay approximation for the curvaton field, recovering standard curvaton and modulated reheating results as limiting cases. We verify the Suyama-Yamaguchi inequality between bispectrum and trispectrum parameters for the primordial density field generated by multiple field fluctuations, and find conditions for the bound to be saturated.

  7. Searches for Exotic Decays of the Upsilon(3S) at BaBar

    SciTech Connect

    Hooberman, Benjamin; /LBL, Berkeley /Heidelberg U.

    2011-12-01

    In this paper we present two searches for new physics in {Upsilon}(3S) decays collected by the BABAR detector. We search for charged lepton-flavour violating decays of the {Upsilon}(3S), which are unobservable in the Standard Model but are predicted to occur in several beyond-the-Standard Model scenarios. We also search for production of a light Higgs or Higgs-like state produced in radiative decays of the {Upsilon}(3S) and decaying to muon pairs.

  8. RARE KAON DECAYS.

    SciTech Connect

    LITTENBERG, L.

    2005-07-19

    Lepton flavor violation (LFV) experiments have probed sensitivities corresponding to mass scales of well over 100 TeV, making life difficult for models predicting accessible LFV in kaon decay and discouraging new dedicated experiments of this type.

  9. Charmless B Decays

    SciTech Connect

    Gradl, Wolfgang; /Edinburgh U.

    2007-03-06

    Rare charmless hadronic B decays are a good testing ground for the standard model. The dominant amplitudes contributing to this class of B decays are CKM suppressed tree diagrams and b {yields} s or b {yields} d loop diagrams (''penguins''). These decays can be used to study interfering standard model (SM) amplitudes and CP violation. They are sensitive to the presence of new particles in the loops, and they provide valuable information to constrain theoretical models of B decays. The B factories BABAR at SLAC and Belle at KEK produce B mesons in the reaction e{sup +}e{sup -} {yields} {Upsilon}(4S) {yields} B{bar B}. So far they have collected integrated luminosities of about 406 fb{sup -1} and 600 fb{sup -1}, respectively. The results presented here are based on subsets of about 200-500 fb{sup -1} and are preliminary unless a journal reference is given.

  10. Duality and decay of macroscopic F strings.

    PubMed

    Skliros, Dimitri P; Copeland, Edmund J; Saffin, Paul M

    2013-07-26

    We study the decay of fundamental string loops of arbitrary size L/min(n,m)≫sqrt[α'], labeled by (n, m; λn, λ[over ¯]m), where n, m correspond to left- and right-mover harmonics and λn, λ[over ¯]m to polarization tensors, and find that a description in terms of the recent coherent vertex operator construction of Hindmarsh and Skliros is computationally very efficient. We primarily show that the decay rates and mass shifts of vertex operators (n, m; λn, λ[over ¯]m) and their "duals" (n, m; λn, λ[over ¯]m*) are equal to leading order in the string coupling, implying, for instance, that decay rates of epicycloids equal those of hypocycloids. We then compute the power and decay rates associated with massless IR radiation for the trajectory (1, 1; λ1, λ[over ¯]1), and find that it is precisely reproduced by the low energy effective theory of Dabholkar and Harvey. Guided by this correspondence, we conjecture the result for arbitrary trajectories (n, m; λn, λ[over ¯]m) and discover a curious relation between gravitational and axion plus dilaton radiation. It is now possible to start exploring string evolution in regimes where a low energy effective description is less useful, such as in the vicinity of cusps. PMID:23931354

  11. Duality and decay of macroscopic F strings.

    PubMed

    Skliros, Dimitri P; Copeland, Edmund J; Saffin, Paul M

    2013-07-26

    We study the decay of fundamental string loops of arbitrary size L/min(n,m)≫sqrt[α'], labeled by (n, m; λn, λ[over ¯]m), where n, m correspond to left- and right-mover harmonics and λn, λ[over ¯]m to polarization tensors, and find that a description in terms of the recent coherent vertex operator construction of Hindmarsh and Skliros is computationally very efficient. We primarily show that the decay rates and mass shifts of vertex operators (n, m; λn, λ[over ¯]m) and their "duals" (n, m; λn, λ[over ¯]m*) are equal to leading order in the string coupling, implying, for instance, that decay rates of epicycloids equal those of hypocycloids. We then compute the power and decay rates associated with massless IR radiation for the trajectory (1, 1; λ1, λ[over ¯]1), and find that it is precisely reproduced by the low energy effective theory of Dabholkar and Harvey. Guided by this correspondence, we conjecture the result for arbitrary trajectories (n, m; λn, λ[over ¯]m) and discover a curious relation between gravitational and axion plus dilaton radiation. It is now possible to start exploring string evolution in regimes where a low energy effective description is less useful, such as in the vicinity of cusps.

  12. Duality and Decay of Macroscopic F Strings

    NASA Astrophysics Data System (ADS)

    Skliros, Dimitri P.; Copeland, Edmund J.; Saffin, Paul M.

    2013-07-01

    We study the decay of fundamental string loops of arbitrary size L/min⁡(n,m)≫α', labeled by (n, m; λn, λ¯m), where n, m correspond to left- and right-mover harmonics and λn, λ¯m to polarization tensors, and find that a description in terms of the recent coherent vertex operator construction of Hindmarsh and Skliros is computationally very efficient. We primarily show that the decay rates and mass shifts of vertex operators (n, m; λn, λ¯m) and their “duals” (n, m; λn, λ¯m*) are equal to leading order in the string coupling, implying, for instance, that decay rates of epicycloids equal those of hypocycloids. We then compute the power and decay rates associated with massless IR radiation for the trajectory (1, 1; λ1, λ¯1), and find that it is precisely reproduced by the low energy effective theory of Dabholkar and Harvey. Guided by this correspondence, we conjecture the result for arbitrary trajectories (n, m; λn, λ¯m) and discover a curious relation between gravitational and axion plus dilaton radiation. It is now possible to start exploring string evolution in regimes where a low energy effective description is less useful, such as in the vicinity of cusps.

  13. Open Flavor Strong Decays

    NASA Astrophysics Data System (ADS)

    García-Tecocoatzi, H.; Bijker, R.; Ferretti, J.; Galatà, G.; Santopinto, E.

    2016-10-01

    In this contribution, we discuss the results of a QM calculation of the open-flavor strong decays of **** light nucleon resonances. These are the results of a recent calculation, where we used a modified ^3P_0 model for the amplitudes and the U(7) algebraic model and the hypercentral quark model to predict the baryon spectrum. The decay amplitudes are compared with the existing experimental data.

  14. Decay Modes of Narrow Molecular Resonances

    SciTech Connect

    Courtin, S.; Haas, F.; Salsac, M.-D.; Lebhertz, D.; Michalon, A.; Beck, C.; Rousseau, M.; Zafra, A. Sanchez I.; Hutcheon, D.; Davis, C.; Pearson, J. E.; Lister, C. J.

    2006-08-14

    The heavy-ion radiative capture reactions 12C(12C,{gamma})24Mg and 12C(16O,{gamma})28Si have been performed on and off resonance at TRIUMF using the Dragon separator and its associated BGO array. The decay of the studied narrow resonances has been shown to proceed predominantly through quasi-bound doorway states which cluster and deformed configurations would have a large overlap with the entry resonance states.

  15. Beta-decay rates

    NASA Astrophysics Data System (ADS)

    Borzov, I. N.

    2006-10-01

    Major astrophysical applications involve a huge number of exotic nuclei. Their beta-decay properties play a crucial role in stellar explosive events. An important effort has been developed in last decades to measure the masses and β-decay properties of very neutron-rich nuclei at radioactive nuclear beam facilities. However, most of them cannot be synthesized in terrestrial laboratories and only theoretical predictions can fill the gap. We will concentrate mainly on the β-decay rates needed for stellar r-process modeling and for performing the RNB experiments. An overview of the microscopic approaches to the β-decay strength function is given. The continuum QRPA approach based on the self-consistent ground state description in the framework of the density functional theory is outlined. For the first time, a systematic study of the total β-decay half-lives and delayed neutron emission probabilities takes into account the Gamow Teller and first-forbidden transitions. Due to the shell configuration effects, the first-forbidden decays have a strong impact on the β-decay characteristics of the r-process relevant nuclei at Z≈28, N>50; Z⩾50, N>82 and Z=60 70, N≈126. Suppression of the delayed neutron emission probability is found in nuclei with the neutron excess bigger than one major shell. The effect originates from the high-energy first-forbidden transitions to the states outside the (Q-B)-window in the daughter nuclei. The performance of existing global models for the nuclides near the r-process paths is critically analyzed and confronted with the recent RIB experiments in the regions of 78Ni, 132Sn and “east” of 208Pb.

  16. HALF-LIVES OF LONG-LIVED ALPHA DECAY, BETA DECAY, ELECTRON CAPTURE DECAY, BETA BETA-DECAY, PROTON DECAY AND SPONTANEOUS FISSION DECAY NUCLIDES.

    SciTech Connect

    HOLDEN, H.E.

    2003-08-08

    In his review of radionuclides for dating purposes, Roth noted that there were a large number of nuclides, normally considered ''stable'' but which are radioactive with a very long half-life. Roth suggested that I review the data on the half-life values of these long-lived nuclides for the 2001 Atomic Weights Commission meeting in Brisbane. I provided a report, BNL-NCS-68377, to fulfill Roth's request. Peiser has now made a similar suggestion that I review these data for our next Commission meeting in Ottawa for their possible inclusion in our Tables. These half-life values for long-lived nuclides include those due to various decay modes, {alpha}-decay, {beta}-decay, electron capture decay, {beta}{beta}-decay, proton decay and spontaneous fission decay. This data review (post Brisbane) provides an update to the recommendation of the 2001 review.

  17. The fitting of radioactive decay data by covariance methods

    SciTech Connect

    Smith, D.L.; Osadebe, F.A.N.

    1994-04-01

    The fitting of radioactive decay data is examined when radiations from two or more processes are indistinguishable. The model is a nonlinear sum of exponentials which cannot be linearized by transformations. Simple and generalized least-squares procedures utilizing covariance matrices are applied. The validity of the midpoint approximation is demonstrated. Guidelines for acquiring adequate radioactive decay data are suggested. The relevance to activation cross section determination is discussed.

  18. Recent Results of {psi}{sup '} decays at BESIII

    SciTech Connect

    Zhang Lei

    2011-05-23

    BES-III at BEPC-II has collected about 106M {psi}{sup '} and 226M J/{psi} events. With these events, many exciting results have been obtained. In this talk, we report the recent results of {psi}{sup '} decays from the BESIII, e.g. h{sub c} production in {psi}{sup '} and {psi}{sup '} radiative decays to the pseudoscalar meson (P = {pi}{sup 0}/{eta}/{eta}{sup '}).

  19. Mitigation of radon and thoron decay products by filtration.

    PubMed

    Wang, Jin; Meisenberg, Oliver; Chen, Yongheng; Karg, Erwin; Tschiersch, Jochen

    2011-09-01

    Inhalation of indoor radon ((222)Rn) and thoron ((220)Rn) decay products is the most important source of exposure to ionizing radiation for the human respiratory tract. Decreasing ventilation rates due to energy saving reasons in new buildings suggest additional active mitigation techniques to reduce the exposure in homes with high radon and thoron concentrations but poor ventilation. Filtration techniques with HEPA filters and simple surgical mask material have been tested for their potential to reduce the indoor exposure in terms of the total effective dose for mixed radon and thoron indoor atmospheres. The tests were performed inside an experimental room providing stable conditions. Filtration (at filtration rates of 0.2 h(-1) and larger) removes attached radon and thoron decay products effectively but indoor aerosol as well. Therefore the concentration of unattached decay products (which have a higher dose coefficient) may increase. The decrease of the attached decay product concentrations could be theoretically described by a slowly decreasing exponential process. For attached radon decay products, it exhibited a faster but weaker removal process compared to attached thoron decay products (-70% for attached radon decay products and -80% for attached thoron decay products at a filtration rate of 0.5 h(-1) with an HEPA filter). The concentration of unattached thoron decay products increased distinctly during the filtration process (+300%) while that of unattached radon decay products rose only slightly though at a much higher level (+17%). In the theoretical description these observed differences could be attributed to the different half-lives of the nuclides. Considering both effects, reduced attached and increased unattached decay product concentrations, filtration could significantly decrease the total effective dose from thoron whereas the overall effect on radon dose is small. A permanent filtration is recommended because of the slow decrease of the thoron

  20. Suppressed Charmed B Decay

    SciTech Connect

    Snoek, Hella Leonie

    2009-06-02

    This thesis describes the measurement of the branching fractions of the suppressed charmed B0 → D*- a0+ decays and the non-resonant B0 → D*- ηπ+ decays in approximately 230 million Υ(4S) → 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 B0 → D*- a{sub 0}+ 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 10-6. 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 γ, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle γ can be performed using the decays of neutral B mesons. The B0 → D*- a0+ decay is sensitive to the angle γ and, in comparison to the current decays that are being employed, could significantly

  1. Decay of superdeformed bands

    SciTech Connect

    Carpenter, M.P.; Khoo, T.L.; Lauritsen, T.

    1995-12-31

    One of the major challenges in the study of superdeformation is to directly connect the large number of superdeformed bands now known to the yrast states. In this way, excitation energies, spins and parities can be assigned to the levels in the second well which is essential to establish the collective and single-particle components of these bands. This paper will review some of the progress which has been made to understand the decay of superdeformed bands using the new arrays including the measurement of the total decay spectrum and the establishment of direct one-step decays from the superdeformed band to the yrast line in {sup 194}Hg. 42 refs., 5 figs.

  2. Kinetics of Radioactive Decay

    NASA Astrophysics Data System (ADS)

    Nagy, S.

    At present there are over 3,000 known nuclides (see the Appendix in Vol. 2 on the “Table of the Nuclides”), 265 of which are stable, while the rest, i.e., more than 90% of them, are radioactive. The chemical applications of the specific isotopes of chemical elements are mostly connected with the latter group, including quite a number of metastable nuclear isomers, making the kinetics of radioactive decay an important chapter of nuclear chemistry. After giving a phenomenological and then a statistical interpretation of the exponential law, the various combinations of individual decay processes as well as the cases of equilibrium and nonequilibrium will be discussed. Half-life systematics of the different decay modes detailed in Chaps. 2 and 4 of this volume are also summarized.

  3. Enhanced Electroweak Penguin Amplitude in B{yields}VV Decays

    SciTech Connect

    Beneke, M.; Rohrer, J.; Yang, D.

    2006-04-14

    We discuss a novel electromagnetic penguin contribution to the transverse helicity amplitudes in B decays to two vector mesons, which is enhanced by two powers of m{sub B}/{lambda} relative to the standard penguin amplitudes. This leads to unique polarization signatures in penguin-dominated decay modes such as B{yields}{rho}K* similar to polarization effects in the radiative decay B{yields}K*{gamma} and offers new opportunities to probe the magnitude and chirality of flavor-changing neutral current couplings to photons.

  4. Prospects for studying penguin decays in LHCb experiments

    SciTech Connect

    Barsuk, S. Ya. Pakhlova, G. V. Belyaev, I. M.

    2006-04-15

    Investigation of loop penguin decays of beauty hadrons seems promising in testing the predictions of the Standard Model of electroweak and strong interactions and in seeking new phenomena beyond the Standard Model. The possibility of studying the radiative penguin decays B{sup 0} {sup {yields}} K*{sup 0}{gamma}, B{sup 0}{sub s} {sup {yields}} {phi}{gamma}, and B{sup 0} {sup {yields}} {omega}{gamma} and the gluonic penguin decays B{sup 0} {sup {yields}} {phi}K{sup 0}{sub S} and B{sup 0}{sub s} {sup {yields}} {phi}{phi} in LHCb experiments is discussed.

  5. Recent BaBar Results on $B$ Decays

    SciTech Connect

    Clark, P.J.; /Edinburgh U.

    2011-11-15

    Several recent key results from the BABAR experiment are presented, most using 383.6 fb{sup -1} of data. In particular, the search for B{sup +} {yields} {tau}{sup +}{nu}, inclusive and exclusive measurements of |V{sub ub}|, measurements of b {yields} d{gamma} decays and new observations of rare charmless hadronic decays. The new results provide important experimental constraints on the Standard Model and new physics models. Keywords: B decays; flavor; leptonic; semi-leptonic, radiative, hadronic.

  6. Penguin and rare decays in BaBar

    SciTech Connect

    Akar, Simon

    2015-04-29

    We present recent results from the BABAR Collaboration on radiative decays. These include searches for new physics via measurements of several observables such as the time- dependent CP asymmetry in B0 → K0Sπ π+γ exclusive decays, as well as direct CP asymmetries and branching fractions in B → Xsγ and B → Xs+ inclusive decays.

  7. Weak decay of hypernuclei

    SciTech Connect

    Grace, R.

    1983-01-01

    The Moby Dick spectrometer (at BNL) in coincidence with a range spectrometer and a TOF neutron detector will be used to study the weak decay modes of /sup 12/C. The Moby Dick spectrometer will be used to reconstruct and tag events in which specific hypernuclear states are formed in the reaction K/sup -/ + /sup 12/C ..-->.. ..pi../sup -/ + /sup 12/C. Subsequent emission of decay products (pions, protons and neutrons) in coincidence with the fast forward pion will be detected in a time and range spectrometer, and a neutron detector.

  8. Search for the decay

    NASA Astrophysics Data System (ADS)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; d'Argent, P.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Birnkraut, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Braun, S.; Brett, D.; Britsch, M.; Britton, T.; Brodzicka, J.; Brook, N. H.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Campana, P.; Campora Perez, D.; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Carvalho Akiba, K.; Casanova Mohr, R.; Casse, G.; Cassina, L.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cavallero, G.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chefdeville, M.; Chen, S.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Dean, C.-T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Di Ruscio, F.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dreimanis, K.; Dujany, G.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H. M.; Evans, T.; Falabella, A.; Färber, C.; Farinelli, C.; Farley, N.; Farry, S.; Fay, R.; Ferguson, D.; Fernandez Albor, V.; Ferrari, F.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fol, P.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; García Pardiñas, J.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gascon, D.; Gaspar, C.; Gastaldi, U.; Gauld, R.; Gavardi, L.; Gazzoni, G.; Geraci, A.; Gerick, D.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Gianì, S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gotti, C.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graverini, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Humair, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Karodia, S.; Kelsey, M.; Kenyon, I. R.; Kenzie, M.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Klimaszewski, K.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Likhomanenko, T.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lucchesi, D.; Lucio Martinez, M.; Luo, H.; Lupato, A.; Luppi, E.; Lupton, O.; Machefert, F.; Maciuc, F.; Maev, O.; Malde, S.; Malinin, A.; Manca, G.; Mancinelli, G.; Manning, P.; Mapelli, A.; Maratas, J.; Marchand, J. F.; Marconi, U.; Marin Benito, C.; Marino, P.; Märki, R.; Marks, J.; Martellotti, G.; Martinelli, M.; Martinez Santos, D.; Martinez Vidal, F.; Martins Tostes, D.; Massafferri, A.; Matev, R.; Mathad, A.; Mathe, Z.; Matteuzzi, C.; Matthieu, K.; Mauri, A.; Maurin, B.; Mazurov, A.; McCann, M.; McCarthy, J.; McNab, A.; McNulty, R.; Meadows, B.; Meier, F.; Meissner, M.; Merk, M.; Milanes, D. A.; Minard, M.-N.; Mitzel, D. S.; Molina Rodriguez, J.; Monteil, S.; Morandin, M.; Morawski, P.; Mordà, A.; Morello, M. J.; Moron, J.; Morris, A. B.; Mountain, R.; Muheim, F.; Müller, J.; Müller, K.; Müller, V.; Mussini, M.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nasteva, I.; Needham, M.; Neri, N.; Neubert, S.; Neufeld, N.; Neuner, M.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Niess, V.; Niet, R.; Nikitin, N.; Nikodem, T.; Ninci, D.; Novoselov, A.; O'Hanlon, D. P.; Oblakowska-Mucha, A.; Obraztsov, V.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Onderwater, C. J. G.; Osorio Rodrigues, B.; Otalora Goicochea, J. M.; Otto, A.; Owen, P.; Oyanguren, A.; Palano, A.; Palombo, F.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Pappalardo, L. L.; Parkes, C.; Passaleva, G.; Patel, G. D.; Patel, M.; Patrignani, C.; Pearce, A.; Pellegrino, A.; Penso, G.; Pepe Altarelli, M.; Perazzini, S.; Perret, P.; Pescatore, L.; Petridis, K.; Petrolini, A.; Petruzzo, M.; Picatoste Olloqui, E.; Pietrzyk, B.; Pilař, T.; Pinci, D.; Pistone, A.; Playfer, S.; Plo Casasus, M.; Poikela, T.; Polci, F.; Poluektov, A.; Polyakov, I.; Polycarpo, E.; Popov, A.; Popov, D.; Popovici, B.; Potterat, C.; Price, E.; Price, J. D.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Puig Navarro, A.; Punzi, G.; Qian, W.; Quagliani, R.; Rachwal, B.; Rademacker, J. H.; Rakotomiaramanana, B.; Rama, M.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Redi, F.; Reichert, S.; Reid, M. M.; dos Reis, A. C.; Ricciardi, S.; Richards, S.; Rihl, M.; Rinnert, K.; Rives Molina, V.; Robbe, P.; Rodrigues, A. B.; Rodrigues, E.; Rodriguez Lopez, J. A.; Rodriguez Perez, P.; Roiser, S.; Romanovsky, V.; Romero Vidal, A.; Rotondo, M.; Rouvinet, J.; Ruf, T.; Ruiz, H.; Ruiz Valls, P.; Saborido Silva, J. J.; Sagidova, N.; Sail, P.; Saitta, B.; Salustino Guimaraes, V.; Sanchez Mayordomo, C.; Sanmartin Sedes, B.; Santacesaria, R.; Santamarina Rios, C.; Santovetti, E.; Sarti, A.; Satriano, C.; Satta, A.; Saunders, D. M.; Savrina, D.; Schiller, M.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmelzer, T.; Schmidt, B.; Schneider, O.; Schopper, A.; Schune, M.-H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Semennikov, A.; Sepp, I.; Serra, N.; Serrano, J.; Sestini, L.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, V.; Shires, A.; Silva Coutinho, R.; Simi, G.; Sirendi, M.; Skidmore, N.; Skillicorn, I.; Skwarnicki, T.; Smith, E.; Smith, E.; Smith, J.; Smith, M.; Snoek, H.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; Souza, D.; Souza De Paula, B.; Spaan, B.; Spradlin, P.; Sridharan, S.; Stagni, F.; Stahl, M.; Stahl, S.; Steinkamp, O.; Stenyakin, O.; Sterpka, F.; Stevenson, S.; Stoica, S.; Stone, S.; Storaci, B.; Stracka, S.; Straticiuc, M.; Straumann, U.; Stroili, R.; Sun, L.; Sutcliffe, W.; Swientek, K.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szczypka, P.; Szumlak, T.; T'Jampens, S.; Tekampe, T.; Teklishyn, M.; Tellarini, G.; Teubert, F.; Thomas, C.; Thomas, E.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Todd, J.; Tolk, S.; Tomassetti, L.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Trabelsi, K.; Tran, M. T.; Tresch, M.; Trisovic, A.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vacca, C.; Vagnoni, V.; Valenti, G.; Vallier, A.; Vazquez Gomez, R.; Vazquez Regueiro, P.; Vázquez Sierra, C.; Vecchi, S.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vieites Diaz, M.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; de Vries, J. A.; Waldi, R.; Wallace, C.; Wallace, R.; Walsh, J.; Wandernoth, S.; Wang, J.; Ward, D. R.; Watson, N. K.; Websdale, D.; Weiden, A.; Whitehead, M.; Wiedner, D.; Wilkinson, G.; Wilkinson, M.; Williams, M.; Williams, M. P.; Williams, M.; Wilson, F. F.; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wright, S.; Wyllie, K.; Xie, Y.; Xu, Z.; Yang, Z.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, L.; Zhang, Y.; Zhelezov, A.; Zhokhov, A.; Zhong, L.

    2015-08-01

    A search for decays is performed using 3 .0 fb1- of pp collision data recorded by the LHCb experiment during 2011 and 2012. The f 0(980) meson is reconstructed through its decay to the π + π - final state in the mass window 900 MeV /c 2 < m( π + π -) < 1080 MeV /c 2. No significant signal is observed. The first upper limits on the branching fraction of are set at 90 % (95 %) confidence level. [Figure not available: see fulltext.

  9. Decay of long-lived particles in the early universe

    NASA Technical Reports Server (NTRS)

    Silk, J.; Stebbins, A.

    1983-01-01

    It is pointed out that radiative decay of massive fermions can distort the cosmic background radiation. The present investigation is concerned with a study of decay lifetimes in the range from 10 to 100,000 years. Attention is given to the physics involved in determining the effect of radiative decay of massive fermions on observed photon backgrounds. The case of particles which decoupled when the effective number of species in equilibrium was in the range from 50 to 100 is considered, and constraints on particle masses and lifetimes are placed on the basis of observed photon fluxes. This approach provides results with special applications to particles predicted by supersymmetry theories and to right-handed neutrinos. Implications for galaxy formation are also discussed.

  10. BABAR B Decay Results

    SciTech Connect

    MacFarlane, David B

    2002-03-14

    Data from the first run of the BABAR detector at the PEP II accelerator are presented. Measurements of many rare B decay modes are now possible using the large data sets currently being collected by BABAR. An overview of analysis techniques and results on data collected in 2000 are described.

  11. Cosmology with decaying particles

    SciTech Connect

    Turner, M.S.

    1984-09-01

    We consider a cosmological model in which an unstable massive relic particle species (denoted by X) has an initial mass density relative to baryons ..beta../sup -1/ identically equal rho/sub X//rho/sub B/ >> 1, and then decays recently (redshift z less than or equal to 1000) into particles which are still relativistic today (denoted by R). We write down and solve the coupled equations for the cosmic scale factor a(t), the energy density in the various components (rho/sub X/, rho/sub R/, rho/sub B/), and the growth of linear density perturbations (delta rho/rho). The solutions form a one parameter (..beta..) family of solutions; physically ..beta../sup -1/ approx. = (..cap omega../sub R//..cap omega../sub NR/) x (1 + z/sub D/) = (ratio today of energy density of relativistic to nonrelativistic particles) x (1 + redshift of (decay)). We discuss the observational implications of such a cosmological model and compare our results to earlier results computed in the simultaneous decay approximation. In an appendix we briefly consider the case where one of the decay products of the X is massive and becomes nonrelativistic by the present epoch. 21 references.

  12. Semileptonic B Meson Decays

    SciTech Connect

    Luth, Vera G.; /SLAC

    2012-01-03

    Semileptonic decays of B mesons play a critical role in the determination of the magnitude of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements V{sub cb} and V{sub ub}. These two quantities are fundamental parameters of the Standard Model and have to be determined experimentally. Over the past decade, the vast samples of B mesons recorded at the B factories at LEP at Cornell University, KEK at Tsukuba, and SLAC at Stanford University have allowed for detailed studies of semileptonic B decays. These decays proceed via first-order weak interactions; thus, they are expected to be free of non-Standard Model contributions and therefore are well suited for the extraction of the quark-mixing parameters. Differential decay rates are combined with theoretical calculations of hadronization effects, leading to a substantially improved knowledge of |V{sub cb}| and |V{sub ub}|. The results are used to constrain the parameters of the CKM matrix and to test the Standard Model predictions for CP-violating effects.

  13. Decay Time of Cathodoluminescence

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2009-01-01

    Simple measurements of the decay time of cathodoluminescence are described. Cathodoluminescence is used in many devices, including computer monitors, oscilloscopes, radar displays and television tubes. The experimental setup is simple and easy to build. Two oscilloscopes, a function generator, and a fast photodiode are needed for the experiments.…

  14. Tooth decay - early childhood

    MedlinePlus

    Bottle mouth; Bottle carries; Baby bottle tooth decay; Early childhood caries (ECC) ... Your child needs strong, healthy baby teeth to chew food and to talk. Baby teeth also make space in children's jaws for their adult teeth to grow in straight. ...

  15. Computer simulations of the motion and decay of global strings

    SciTech Connect

    Hagmann, C.; Sikivie, P.

    1990-01-01

    Computer simulations have been carried out of the motion and decay of global strings, including spectrum analysis of the energy stored in the scalar field which describes the global string and the radiated Nambu-Goldstone bosons. We simulated relaxing pieces of bent string and collapsing loops. We find, for the string sizes investigated, that the spectrum of field energy hardens rather than softens while the string decays into Nambu-Goldstone radiation. We argue on theoretical grounds that is indeed the most plausible general behaviour. 19 refs., 12 figs.

  16. Sound decay of notes from acoustic guitars

    NASA Astrophysics Data System (ADS)

    Galazen, Erika; Nordberg, Joni; Huber, Thomas M.

    2005-09-01

    The acoustic guitar produces tones by transferring energy from the strings, through the bridge to the top plate, back, and air cavity of the guitar. The vibrations are ultimately radiated into the air as sound. The air-cavity and body resonances of the guitar play an important role in both the tone and the sustain (the time it takes notes to decay) produced by the guitar. To study the relationship between resonances of the guitar and the sustain of notes, the resonance frequencies were measured using a mechanical shaker attached to the body of the guitar and laser Doppler vibrometer to measure its vibration. A string was tuned to different frequencies and plucked. The decay of the note was measured with an electromagnetic pickup that measured the vibration of the string, a vibrometer to measure vibration of the top plate, and microphones located inside and outside the guitar. As expected, when the fundamental frequency of the string was near one of the resonances of the guitar, the decay rate was faster (shorter sustain) than when the string was between resonances. The relationship between the decay rates of the different parts of the system will also be discussed.

  17. Rare Decays of the ɛ Meson

    NASA Astrophysics Data System (ADS)

    Papandreou, Zisis

    2006-02-01

    A study of several rare η decays near threshold was carried out at the C-6 (π-) beamline of the Alternating Gradient Synchrotron at Brookhaven National Laboratory with the Crystal Ball detector, an electromagnetic calorimeter with nearly 4π geometric acceptance that is comprised of 672 optically isolated NaI(Tl) crystals with a thickness of 15.7 radiation lengths. Results from the search for the CP forbidden decay η → 4π0 and the investigation of the quadratic slope parameter in η → 3π0 decay will be profiled, among others. The focus of the talk will be on the η → π0γγ rare decay: its relative branching ratio was extracted to be B1 = (8.3 ± 2.8 ± 1.2) × 10-4, based on the analysis of 3 × 107 detected η mesons. This leads to a partial width for the eta meson of Γ(η → π0γγ) = (0.32 ± 0.15) eV/c2, a value much lower than past measurements and in line with Chiral Perturbation Theory calculations.

  18. Anatomy of decays

    NASA Astrophysics Data System (ADS)

    Bel, Lennaert; De Bruyn, Kristof; Fleischer, Robert; Mulder, Mick; Tuning, Niels

    2015-07-01

    The decays B {/d 0} → D {/d -} D {/d +} and B {/s 0} → D {/s -} D {/s +} probe the CP-violating mixing phases ϕ d and ϕ s , respectively. The theoretical uncertainty of the corresponding determinations is limited by contributions from penguin topologies, which can be included with the help of the U-spin symmetry of the strong interaction. We analyse the currently available data for B {/d, s 0} → D {/d, s -} D {/d, s +} decays and those with similar dynamics to constrain the involved non-perturbative parameters. Using further information from semileptonic B {/d 0} → D {/d -} ℓ + ν ℓ decays, we perform a test of the factorisation approximation and take non-factorisable SU(3)-breaking corrections into account. The branching ratios of the B {/d 0} → D {/d -} D {/d +}, B {/s 0} → D {/s -} D {/d +} and B {/s 0} → D {/s -} D {/s +}, B {/d 0} → D {/d -} D {/s +} decays show an interesting pattern which can be accommodated through significantly enhanced exchange and penguin annihilation topologies. This feature is also supported by data for the B {/s 0} → D {/d -} D {/d +} channel. Moreover, there are indications of potentially enhanced penguin contributions in the B {/d 0} → D {/d -} D {/d +} and B {/s 0} → D {/s -} D {/s +} decays, which would make it mandatory to control these effects in the future measurements of ϕ d and ϕ s . We discuss scenarios for high-precision measurements in the era of Belle II and the LHCb upgrade.

  19. Observation of the competitive double-gamma nuclear decay.

    PubMed

    Walz, C; Scheit, H; Pietralla, N; Aumann, T; Lefol, R; Ponomarev, V Yu

    2015-10-15

    The double-gamma (γγ)-decay of a quantum system in an excited state is a fundamental second-order process of quantum electrodynamics. In contrast to the well-known single-gamma (γ)-decay, the γγ-decay is characterized by the simultaneous emission of two γ quanta, each with a continuous energy spectrum. In nuclear physics, this exotic decay mode has only been observed for transitions between states with spin-parity quantum numbers J(π) = 0(+) (refs 1-3). Single-gamma decays-the main experimental obstacle to observing the γγ-decay-are strictly forbidden for these 0(+) → 0(+) transitions. Here we report the observation of the γγ-decay of an excited nuclear state (J(π) = 11/2(-)) that is directly competing with an allowed γ-decay (to ground state J(π) = 3/2(+)). The branching ratio of the competitive γγ-decay of the 11/2(-) isomer of (137)Ba to the ground state relative to its single γ-decay was determined to be (2.05 ± 0.37) × 10(-6). From the measured angular correlation and the shape of the energy spectra of the individual γ-rays, the contributing combinations of multipolarities of the γ radiation were determined. Transition matrix elements calculated using the quasiparticle-phonon model reproduce our measurements well. The γγ-decay rate gives access to so far unexplored important nuclear structure information, such as the generalized (off-diagonal) nuclear electric polarizabilities and magnetic susceptibilities.

  20. Observation of the competitive double-gamma nuclear decay.

    PubMed

    Walz, C; Scheit, H; Pietralla, N; Aumann, T; Lefol, R; Ponomarev, V Yu

    2015-10-15

    The double-gamma (γγ)-decay of a quantum system in an excited state is a fundamental second-order process of quantum electrodynamics. In contrast to the well-known single-gamma (γ)-decay, the γγ-decay is characterized by the simultaneous emission of two γ quanta, each with a continuous energy spectrum. In nuclear physics, this exotic decay mode has only been observed for transitions between states with spin-parity quantum numbers J(π) = 0(+) (refs 1-3). Single-gamma decays-the main experimental obstacle to observing the γγ-decay-are strictly forbidden for these 0(+) → 0(+) transitions. Here we report the observation of the γγ-decay of an excited nuclear state (J(π) = 11/2(-)) that is directly competing with an allowed γ-decay (to ground state J(π) = 3/2(+)). The branching ratio of the competitive γγ-decay of the 11/2(-) isomer of (137)Ba to the ground state relative to its single γ-decay was determined to be (2.05 ± 0.37) × 10(-6). From the measured angular correlation and the shape of the energy spectra of the individual γ-rays, the contributing combinations of multipolarities of the γ radiation were determined. Transition matrix elements calculated using the quasiparticle-phonon model reproduce our measurements well. The γγ-decay rate gives access to so far unexplored important nuclear structure information, such as the generalized (off-diagonal) nuclear electric polarizabilities and magnetic susceptibilities. PMID:26469051

  1. B Decays Involving Light Mesons

    NASA Astrophysics Data System (ADS)

    Eschrich, Ivo Gough

    Recent BABAR results for decays of B-mesons to combinations of non-charm mesons are presented. This includes B decays to two vector mesons, B → η‧(π, K, ρ) modes, and a comprehensive Dalitz Plot analysis of B → KKK decays.

  2. B Decays Involving Light Mesons

    SciTech Connect

    Eschrich, Ivo Gough; /UC, Irvine

    2007-01-09

    Recent BABAR results for decays of B-mesons to combinations of non-charm mesons are presented. This includes B decays to two vector mesons, B {yields} {eta}{prime}({pi}, K, {rho}) modes, and a comprehensive Dalitz Plot analysis of B {yields} KKK decays.

  3. Decay Dynamics of Tumors

    PubMed Central

    2016-01-01

    The fractional cell kill is a mathematical expression describing the rate at which a certain population of cells is reduced to a fraction of itself. We investigate the mathematical function that governs the rate at which a solid tumor is lysed by a cell population of cytotoxic lymphocytes. We do it in the context of enzyme kinetics, using geometrical and analytical arguments. We derive the equations governing the decay of a tumor in the limit in which it is plainly surrounded by immune cells. A cellular automaton is used to test such decay, confirming its validity. Finally, we introduce a modification in the fractional cell kill so that the expected dynamics is attained in the mentioned limit. We also discuss the potential of this new function for non-solid and solid tumors which are infiltrated with lymphocytes. PMID:27310010

  4. Nuclear Properties and Decay Data Chart of Nuclides.

    2008-04-04

    Version 00 NUCHART displays nuclear decay data graphically on a PC and, includes a search routine for assigning gamma-ray energies to radionuclides. The numerical data included in NUCHART were taken from the online database "NUDAT" Version of March 1994. The following information is presented: (1) Nuclide information: for each nuclide, abundance, mass excess, (main) decay mode, half-life and uncertainty, branching ratio, decay Q; (2) decay radiation: for each nuclide, tables of radiation energy, intensity andmore » equivalent dose for the 5 most intense decay radiations of beta+, beta-, conversion electrons, gammas, alphas and x-rays, including electron Augers; (3) adopted gammas: for each nuclide, table containing energy, relative intensity, energy level of the main gamma lines and year of publication in Nuclear Data Sheets; (4) search gamma energies: for a specified interval of gamma energies all know gamma lines and their nuclides are displayed; the database contains 132,000 gamma lines; (5) a search mode by specific nuclide is also available. For the latest data and online tools for viewing the data, see NuDat 2.4 on the NNDC and IAEA NDS websites: http://www.nndc.bnl.gov/ and http://www-nds.iaea.org/.« less

  5. Nuclear Properties and Decay Data Chart of Nuclides.

    SciTech Connect

    OSORIO, V. B.

    2008-04-04

    Version 00 NUCHART displays nuclear decay data graphically on a PC and, includes a search routine for assigning gamma-ray energies to radionuclides. The numerical data included in NUCHART were taken from the online database "NUDAT" Version of March 1994. The following information is presented: (1) Nuclide information: for each nuclide, abundance, mass excess, (main) decay mode, half-life and uncertainty, branching ratio, decay Q; (2) decay radiation: for each nuclide, tables of radiation energy, intensity and equivalent dose for the 5 most intense decay radiations of beta+, beta-, conversion electrons, gammas, alphas and x-rays, including electron Augers; (3) adopted gammas: for each nuclide, table containing energy, relative intensity, energy level of the main gamma lines and year of publication in Nuclear Data Sheets; (4) search gamma energies: for a specified interval of gamma energies all know gamma lines and their nuclides are displayed; the database contains 132,000 gamma lines; (5) a search mode by specific nuclide is also available. For the latest data and online tools for viewing the data, see NuDat 2.4 on the NNDC and IAEA NDS websites: http://www.nndc.bnl.gov/ and http://www-nds.iaea.org/.

  6. Charmless b decays at CDF

    SciTech Connect

    Donega, Mauro; /Geneva U.

    2005-07-01

    The authors report on the charmless B decays measurements performed on 180 pb{sup -1} of data collected with the CDF II detector at the Fermilab Tevatron collider. This paper describes: the first observation of the decay mode B{sub s} {yields} K{sup +}K{sup -} and the measurement of the direct Cp asymmetry in the ({bar B}){sub d} {yields} K{sup {+-}}{pi}{sup {-+}} decay; the first evidence of the decay mode B{sub s} {yields} {phi}{phi} and the branching ratio and Cp asymmetry for the B{sup {+-}} {yields} {phi}K{sup {+-}} decay.

  7. Rare top quark decays in Alternative Left-Right Symmetric Models

    SciTech Connect

    Gaitan, R.; Miranda, O. G.; Cabral-Rosetti, L. G.

    2007-06-19

    We evaluate the flavor changing neutral currents (FCNC) decay t {yields} H0 + c in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions; the FCNC decays may place at tree level and are only supressed by the mixing between ordinary top and charm quarks. We also comment on the decay process t {yields} c + {gamma}, which involves radiative corrections.

  8. Measurement of upper limits for {upsilon}{yields}{gamma}+R decays

    SciTech Connect

    Rosner, J. L.; Adam, N. E.; Alexander, J. P.; Cassel, D. G.; Duboscq, J. E.; Ehrlich, R.; Fields, L.; Galik, R. S.; Gibbons, L.; Gray, R.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.; Hertz, D.; Jones, C. D.; Kandaswamy, J.; Kreinick, D. L.; Kuznetsov, V. E.; Mahlke-Krueger, H.; Onyisi, P. U. E.

    2007-12-01

    We report on a study of exclusive radiative decays {upsilon}(nS){yields}{gamma}+R (n=1, 2, 3), with R a narrow resonant hadronic state decaying into four or more charged particles (plus possible neutrals). Using data collected from the CLEO III detector at the Cornell Electron Storage Ring, we present upper limits of order 10{sup -4} for such bottomonium two-body decays as a function of the mass M{sub R} recoiling opposite the photon.

  9. Rare decay {eta}{r_arrow}{pi}{pi}{gamma}{gamma} in chiral perturbation theory

    SciTech Connect

    Knoechlein, G.; Scherer, S.; Drechsel, D.

    1996-04-01

    We investigate the rare radiative {eta} decay modes {eta}{r_arrow}{pi}{sup +}{pi}{sup {minus}}{gamma}{gamma} and {eta}{r_arrow}{pi}{sup 0}{pi}{sup 0}{gamma}{gamma} within the framework of chiral perturbation theory at {ital O}({ital p}{sup 4}). We present photon spectra and partial decay rates for both processes as well as a Dalitz contour plot for the charged decay. {copyright} {ital 1996 The American Physical Society.}

  10. The decay of the 1973 August 9 flare

    NASA Technical Reports Server (NTRS)

    Dere, K. P.; Cook, J. W.

    1979-01-01

    The state and evolution of the decay-phase plasma from a compact solar flare that occurred on August 9, 1973, are investigated on the basis of XUV and X-ray observations from Skylab and Solrad 9. Density-sensitive line ratios are used to determine the electron density over the temperature range from 30,000 to 5 million K, and the differential emission measure in the temperature interval from 30,000 to 20 million K is derived for several times in the decay phase. The morphology of the flare is discussed, including its relation to the observed photospheric magnetic field. The sequential formation of new loops during the decay phase is emphasized as an essential element for understanding the decay phase of the flare. This idea is developed further by comparing the observed differential emission measure with that predicted by a semiempirical model which considers the sequential formation of isothermal loops that cool by radiation and thermal conduction.

  11. Constraints on vacuum decay from the microwave background

    NASA Technical Reports Server (NTRS)

    Overduin, J. M.; Wesson, P. S.; Bowyer, S.

    1993-01-01

    We consider the possible decay of a vacuum with nonzero energy density into radiation. This is one way to introduce a time-varying cosmological constant, which has been suggested as a means of resolving the cosmological constant problem. We concentrate on the model of Freese et al., in which the vacuum energy density is given as a fraction x/(1 - x) of the energy density of radiation. Using equations for the visible extragalactic background light and assuming that the vacuum decay energy is converted entirely into photons with a Planckian spectrum, we show that the decay process would be capable of contributing significantly to the intensity of the cosmic microwave background. Comparison with COBE observations leads to the constraint x is equal to or less than 0.001, which is stronger than the upper limit of 0.07 obtained previously by Freese et al. from considerations of primordial nucleosynthesis.

  12. Project 8: Determining neutrino mass from tritium beta decay using a frequency-based method

    SciTech Connect

    Doe, Peter J.; Kofron, Jared N.; MCBride, Lisa; Robertson, R. G. H.; Rosenberg, Leslie; Rybka, Gray; Doelman, S.; Rogers, Alan E.; Formaggio, Joseph; Furse, Daniel; Oblath, Noah S.; LaRoque, Benjamin; Leber, Michelle; Monreal, Ben; Bahr, Matthew; Asner, David M.; Jones, Anthony M.; Fernandes, Justin L.; VanDevender, Brent A.; Patterson, Ryan B.; Bradley, Rich; Thummler, Thomas

    2013-10-04

    A general description is given of Project 8, a new approach to measuring the neutrino mass scale via the beta decay of tritium. In Project 8, the energy of electrons emitted in beta decay is determined from the frequency of cyclotron radiation emitted as the electrons spiral in a uniform magnetic field

  13. Complex decay patterns in atomic core photoionization disentangled by ion-recoil measurements

    SciTech Connect

    Guillemin, Renaud; Bomme, Cedric; Marin, Thierry; Journel, Loic; Marchenko, Tatiana; Kushawaha, Rajesh K.; Piancastelli, Maria Novella; Simon, Marc; Trcera, Nicolas

    2011-12-15

    Following core 1s ionization and resonant excitation of argon atoms, we measure the recoil energy of the ions due to momentum conservation during the emission of Auger electrons. We show that such ion momentum spectroscopy can be used to disentangle to some degree complex decay patterns, involving both radiative and nonradiative decays.

  14. Preliminary Therapy Evaluation of (225)Ac-DOTA-c(RGDyK) Demonstrates that Cerenkov Radiation Derived from (225)Ac Daughter Decay Can Be Detected by Optical Imaging for In Vivo Tumor Visualization.

    PubMed

    Pandya, Darpan N; Hantgan, Roy; Budzevich, Mikalai M; Kock, Nancy D; Morse, David L; Batista, Izadora; Mintz, Akiva; Li, King C; Wadas, Thaddeus J

    2016-01-01

    The theranostic potential of (225)Ac-based radiopharmaceuticals continues to increase as researchers seek innovative ways to harness the nuclear decay of this radioisotope for therapeutic and imaging applications. This communication describes the evaluation of (225)Ac-DOTA-c(RGDyK) in both biodistribution and Cerenkov luminescence imaging (CLI) studies. Initially, La-DOTA-c(RGDyK) was prepared as a non-radioactive surrogate to evaluate methodologies that would contribute to an optimized radiochemical synthetic strategy and estimate the radioactive conjugate's affinity for αvβ3, using surface plasmon resonance spectroscopy. Surface plasmon resonance spectroscopy studies revealed the IC50 and Ki of La-DOTA-c(RGDyK) to be 33 ± 13 nM and 26 ± 11 nM, respectively, and suggest that the complexation of the La(3+) ion to the conjugate did not significantly alter integrin binding. Furthermore, use of this surrogate allowed optimization of radiochemical synthesis strategies to prepare (225)Ac-DOTA-c(RGDyK) with high radiochemical purity and specific activity similar to other (225)Ac-based radiopharmaceuticals. This radiopharmaceutical was highly stable in vitro. In vivo biodistribution studies confirmed the radiotracer's ability to target αvβ3 integrin with specificity; specificity was detected in tumor-bearing animals using Cerenkov luminescence imaging. Furthermore, tumor growth control was achieved using non-toxic doses of the radiopharmaceutical in U87mg tumor-bearing nude mice. To our knowledge, this is the first report to describe the CLI of αvβ3 (+) tumors in live animals using the daughter products derived from (225)Ac decay in situ. This concept holds promise to further enhance development of targeted alpha particle therapy.

  15. Preliminary Therapy Evaluation of (225)Ac-DOTA-c(RGDyK) Demonstrates that Cerenkov Radiation Derived from (225)Ac Daughter Decay Can Be Detected by Optical Imaging for In Vivo Tumor Visualization.

    PubMed

    Pandya, Darpan N; Hantgan, Roy; Budzevich, Mikalai M; Kock, Nancy D; Morse, David L; Batista, Izadora; Mintz, Akiva; Li, King C; Wadas, Thaddeus J

    2016-01-01

    The theranostic potential of (225)Ac-based radiopharmaceuticals continues to increase as researchers seek innovative ways to harness the nuclear decay of this radioisotope for therapeutic and imaging applications. This communication describes the evaluation of (225)Ac-DOTA-c(RGDyK) in both biodistribution and Cerenkov luminescence imaging (CLI) studies. Initially, La-DOTA-c(RGDyK) was prepared as a non-radioactive surrogate to evaluate methodologies that would contribute to an optimized radiochemical synthetic strategy and estimate the radioactive conjugate's affinity for αvβ3, using surface plasmon resonance spectroscopy. Surface plasmon resonance spectroscopy studies revealed the IC50 and Ki of La-DOTA-c(RGDyK) to be 33 ± 13 nM and 26 ± 11 nM, respectively, and suggest that the complexation of the La(3+) ion to the conjugate did not significantly alter integrin binding. Furthermore, use of this surrogate allowed optimization of radiochemical synthesis strategies to prepare (225)Ac-DOTA-c(RGDyK) with high radiochemical purity and specific activity similar to other (225)Ac-based radiopharmaceuticals. This radiopharmaceutical was highly stable in vitro. In vivo biodistribution studies confirmed the radiotracer's ability to target αvβ3 integrin with specificity; specificity was detected in tumor-bearing animals using Cerenkov luminescence imaging. Furthermore, tumor growth control was achieved using non-toxic doses of the radiopharmaceutical in U87mg tumor-bearing nude mice. To our knowledge, this is the first report to describe the CLI of αvβ3 (+) tumors in live animals using the daughter products derived from (225)Ac decay in situ. This concept holds promise to further enhance development of targeted alpha particle therapy. PMID:27022417

  16. Preliminary Therapy Evaluation of 225Ac-DOTA-c(RGDyK) Demonstrates that Cerenkov Radiation Derived from 225Ac Daughter Decay Can Be Detected by Optical Imaging for In Vivo Tumor Visualization

    PubMed Central

    Pandya, Darpan N.; Hantgan, Roy; Budzevich, Mikalai M.; Kock, Nancy D.; Morse, David L.; Batista, Izadora; Mintz, Akiva; Li, King C.; Wadas, Thaddeus J.

    2016-01-01

    The theranostic potential of 225Ac-based radiopharmaceuticals continues to increase as researchers seek innovative ways to harness the nuclear decay of this radioisotope for therapeutic and imaging applications. This communication describes the evaluation of 225Ac-DOTA-c(RGDyK) in both biodistribution and Cerenkov luminescence imaging (CLI) studies. Initially, La-DOTA-c(RGDyK) was prepared as a non-radioactive surrogate to evaluate methodologies that would contribute to an optimized radiochemical synthetic strategy and estimate the radioactive conjugate's affinity for αvβ3, using surface plasmon resonance spectroscopy. Surface plasmon resonance spectroscopy studies revealed the IC50 and Ki of La-DOTA-c(RGDyK) to be 33 ± 13 nM and 26 ± 11 nM, respectively, and suggest that the complexation of the La3+ ion to the conjugate did not significantly alter integrin binding. Furthermore, use of this surrogate allowed optimization of radiochemical synthesis strategies to prepare 225Ac-DOTA-c(RGDyK) with high radiochemical purity and specific activity similar to other 225Ac-based radiopharmaceuticals. This radiopharmaceutical was highly stable in vitro. In vivo biodistribution studies confirmed the radiotracer's ability to target αvβ3 integrin with specificity; specificity was detected in tumor-bearing animals using Cerenkov luminescence imaging. Furthermore, tumor growth control was achieved using non-toxic doses of the radiopharmaceutical in U87mg tumor-bearing nude mice. To our knowledge, this is the first report to describe the CLI of αvβ3+ tumors in live animals using the daughter products derived from 225Ac decay in situ. This concept holds promise to further enhance development of targeted alpha particle therapy. PMID:27022417

  17. E6 Gamma Decay

    SciTech Connect

    Brown, B. Alex; Rae, W. D. M.

    2011-05-06

    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.

  18. The observation of decay

    NASA Astrophysics Data System (ADS)

    Sudbery, A.

    1984-10-01

    It is argued that the usual formulation of quantum mechanics does not satisfactorily describe physical change: the standard formula for a transition probability does not follow from the postulates. Instead, these yield the paradox that a watched pot never bolls (sometimes called "Zeno's paradox"). The paradox is reviewed and the possibility of avoiding it is discussed. A simple model of a decaying system is analysed; the system is then considered in continuous interaction with an apparatus designed to observe the time development of the system. In the light of this analysis, the possibility is considered of replacing the usual (diserete) projection postulate by a continuous projection postulate.

  19. Rare B Decays

    SciTech Connect

    Jackson, P.D.; /Victoria U.

    2006-02-24

    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 -}.

  20. Rare decays and CP asymmetries in charged B decays

    SciTech Connect

    Deshpande, N.G.

    1991-01-01

    The theory of loop induced rare decays and the rate asymmetry due to CP violation in charged B Decays in reviewed. After considering b {yields} s{gamma} and b {yields} se{sup +}e{sup {minus}} decays, the asymmetries for pure penguin process are estimated first. A larger asymmetry can result in those modes where a tree diagram and a penguin diagram interfere, however these estimates are necessarily model dependent. Estimates of Cabbibo suppressed penguins are also considered.

  1. Wood decay at sea

    NASA Astrophysics Data System (ADS)

    Charles, François; Coston-Guarini, Jennifer; Guarini, Jean-Marc; Fanfard, Sandrine

    2016-08-01

    The oceans and seas receive coarse woody debris since the Devonian, but the kinetics of wood degradation remains one of many unanswered questions about the fate of driftwood in the marine environment. A simple gravimetric experiment was carried out at a monitoring station located at the exit of a steep, forested Mediterranean watershed in the Eastern Pyrenees. The objective was to describe and quantify, with standardized logs (in shape, structure and constitution), natural degradation of wood in the sea. Results show that the mass decrease of wood logs over time can be described by a sigmoidal curve. The primary process of wood decay observed at the monitoring station was due to the arrival and installation of wood-boring species that consumed more than half of the total wood mass in six months. Surprisingly, in a region where there is little remaining wood marine infrastructure, "shipworms", i.e. xylophagous bivalves, are responsible for an important part of this wood decay. This suggests that these communities are maintained probably by a frequent supply of a large quantity of riparian wood entering the marine environment adjacent to the watershed. By exploring this direct link between terrestrial and marine ecosystems, our long term objective is to determine how these supplies of terrestrial organic carbon can sustain wood-based marine communities as it is observed in the Mediterranean Sea.

  2. Soudan nucleon decay program

    SciTech Connect

    Ayres, D.S.

    1981-01-01

    The Soudan nucleon decay program is being carried out in the Soudan iron mine in northeastern Minnesota, at a depth of 2000 m of water equivalent. A 30-ton prototype experiment, Soudan 1, has been built and is now being operated by a University of Minnesota - Argonne National Laboratory collaboration. The detector is a block of iron-loaded concrete instrumented with 3456 gas proportional tubes. It can detect nucleon decay at the 2 x 10/sup 30/ year level, and will measure cosmic-ray induced backgrounds. Soudan 1 is also obtaining data on very high energy cosmic-ray interactions. Monte-Carlo predictions of performance have been checked by calibration of a detector module in a charged-particle test beam. A proposal to build a 1000-ton experiment, Soudan 2, has been submitted to funding agencies in the USA and the UK by a Minnesota - Argonne - Oxford University collaboration. The proposed detector utilizes drift chambers with 50-cm drifts to obtain very fine-grained ionization and tracking information at low cost. This tracking-calorimeter detector has a fiducial mass of 650 tons, and could be operating in 1985. A drifting scheme utilizing 50 cm x 5 m x 1 cm planar chambers has been shown feasible, and prototypes of alternate drifting structures are also being studied. A plan to provide expandability to an eventual 5000 tons has been developed.

  3. Monticello BWR spent fuel assembly decay heat predictions and measurements

    SciTech Connect

    McKinnon, M.A.; Doman, J.W.; Heeb, C.M.; Creer, J.M.

    1986-06-01

    This report compares pre-calorimetry predictions of rates of six 7 x 7 boiling water reactor (BWR) spent fuel assemblies with measured decay heat rates. The assemblies were from Northern States Power Company's Monticello Nuclear Generating Plant and had burnups of 9 to 21 GWd/MTU and cooling times of 9 to 10 years. Conclusions are: The agreement between ORIGEN2 predictions and decay heat measurements of Monticello spent fuel is dependent on the method used to calibrate the calorimeter and to make the decay heat measurements. The agreement between predictions and measurements of decay heat rates of Monticello fuel is the same as that for Cooper and Dresden fuel if the same measurement method is used. The predictions are within a standard deviation of +-15 W of the measurements. Using a different measurement method, ORIGEN2 underpredicts the measured decay heat output of Monticello fuel assemblies by a constant 20 +- 2 W. The 20-W offset appears to be an artifact of the calibration procedure. The constant term in the calibration curve (i.e., q/sub DH/ = mx + b) can account for measurement differences of 40 W based on the 1983, 1984, and 1985 calibration curves. The difference between ORIGEN2 predictions and calorimeter decay heat measurements does not appear to be dependent on the magnitude of decay heat output. Predicted axial decay heat profiles are in good agreement with measured axial gamma radiation profiles. Recommendations are: Predictions using other decay heat codes should be compared to experimental data contained in this report, to evaluate prediction capabilities. The source of the differences that exist among calorimeter calibration curves needs to be determined. Calorimeter operational methods need to be investigated further to determine cause and effect relationships between operational method and calorimeter precision and accuracy.

  4. Alpha decay in electron surrounding

    SciTech Connect

    Igashov, S. Yu.; Tchuvil’sky, Yu. M.

    2013-12-15

    The influence of atomic electron shells on the constant of alpha decay of heavy and mediummass nuclei was considered in detail. A method for simultaneously taking into account the change in the potential-barrier shape and the effect of reflection of a diverging Coulomb wave in the classically allowed region was developed. The ratios of decay probabilities per unit time for a bare nucleus and the respective neutral atom were found for some alpha-decaying isotopes.

  5. Review of semileptonic charm decays

    SciTech Connect

    Potter, D.M.

    1991-01-01

    The experimental status of D{sup 0} and D{sup +} semileptonic decays is reviewed and compared to model predictions. Topics covered are the form factor pole mass and decay rate for D {yields} Klv, the decay rate and form factor ratios for D {yields} K*lv, and, finally, the issue of modes other than Klv and K*lv. 4 refs., 5 tabs.

  6. Beta decay of polarized neutrons

    SciTech Connect

    Bopp, P.; Dubbers, D.; Hornig, L.; Klemt, E.; Last, J.; Schuetze, H.; Freedman, S.J.; Schaerpf, O.

    1985-01-15

    Beta decay of polarized neutrons has been studied with the superconductive spectrometer PERKEO at the Institut Laue-Langevin. The energy spectrum of the ..beta..-decay asymmetry has been measured for the first time; from the absolute value of the asymmetry we obtain a new value for the ratio of weak coupling constants g/sub A//g/sub V/, which is compared to similar data from hyperon decays. The measurement of further weak interaction parameters from neutron decay is in progress.

  7. Rare B Decays at Babar

    SciTech Connect

    Palombo, Fernando; Collaboration, for the BABAR

    2009-01-12

    The author presents some of the most recent BABAR measurements for rare B decays. These include rate asymmetries in the B decays to K{sup (*)}l{sup +}l{sup -} and K{sup +}{pi}{sup -} and branching fractions in the B decays to l{sup +}{nu}{sub l}, K{sub 1}(1270){sup +}{pi}{sup -} and K{sub 1}(1400){sup +}{pi}{sup -}. The author also reports a search for the B{sup +} decay to K{sub S}{sup 0}K{sub S}{sup 0}{pi}{sup +}.

  8. Evidence for a Solar Influence on Nuclear Decay Rates

    NASA Astrophysics Data System (ADS)

    Sturrock, Peter A.; Buncher, J. B.; Fischbach, E.; Gruenwald, J. T.; Javorsek, D., II; Jenkins, J. H.; Lee, R.; Mattes, J. T.; Newport, J. R.

    2010-05-01

    Analyses of data acquired during two experiments at the Brookhaven National Laboratory (BNL) and one at the Physikalisch-Technische Bundesanstalt in Germany have yielded strong evidence for an annual variation of some nuclear decay rates. Since the Sun-Earth distance has an annual period, it is possible that some radiation from the Sun plays a role. We here present evidence in support of this conjecture. The low-energy solar-neutrino flux as detected by the Homestake and GALLEX experiments, and the total solar irradiance as measured by the ACRIM experiment, both exhibit a periodicity of about 12 year-1. We infer that the solar core rotates at this synodic frequency, and that nuclear burning in the core is not spherically symmetric. If neutrinos influence some decay rates, the same periodicity may be manifested in decay measurements. We have for this reason carried out a power-spectrum analysis of measurements made at BNL over a 7-year interval of the decay rates of 32Si and 36Cl. This analysis yields strong evidence for a cluster of periodicities centered on 12 year-1, such as one might obtain from stochastic fluctuations of nuclear burning in a rotating core. These results imply that some nuclear decay rates are influenced either by solar neutrinos or by some other form of radiation that has its origin in the solar core. This work was supported by the NSF grant AST-0607572 and DOE grant DE-AC-02-76ER071428.

  9. Constraining decaying dark matter with Fermi LAT gamma-rays

    SciTech Connect

    Zhang, Le; Sigl, Günter; Weniger, Christoph; Maccione, Luca; Redondo, Javier E-mail: christoph.weniger@desy.de E-mail: redondo@mppmm.mpg.de

    2010-06-01

    High energy electrons and positrons from decaying dark matter can produce a significant flux of gamma rays by inverse Compton off low energy photons in the interstellar radiation field. This possibility is inevitably related with the dark matter interpretation of the observed PAMELA and FERMI excesses. The aim of this paper is providing a simple and universal method to constrain dark matter models which produce electrons and positrons in their decay by using the Fermi LAT gamma-ray observations in the energy range between 0.5 GeV and 300 GeV. We provide a set of universal response functions that, once convolved with a specific dark matter model produce the desired constraints. Our response functions contain all the astrophysical inputs such as the electron propagation in the galaxy, the dark matter profile, the gamma-ray fluxes of known origin, and the Fermi LAT data. We study the uncertainties in the determination of the response functions and apply them to place constraints on some specific dark matter decay models that can well fit the positron and electron fluxes observed by PAMELA and Fermi LAT. To this end we also take into account prompt radiation from the dark matter decay. We find that with the available data decaying dark matter cannot be excluded as source of the PAMELA positron excess.

  10. Decay of oscillating universes

    NASA Astrophysics Data System (ADS)

    Mithani, Audrey Todhunter

    It has been suggested by Ellis et al that the universe could be eternal in the past, without beginning. In their model, the "emergent universe'' exists forever in the past, in an "eternal'' phase before inflation begins. We will show that in general, such an "eternal'' phase is not possible, because of an instability due to quantum tunneling. One candidate model, the "simple harmonic universe'' has been shown by Graham et al to be perturbatively stable; we find that it is unstable with respect to quantum tunneling. We also investigate the stability of a distinct oscillating model in loop quantum cosmology with respect to small perturbations and to quantum collapse. We find that the model has perturbatively stable and unstable solutions, with both types of solutions occupying significant regions of the parameter space. All solutions are unstable with respect to collapse by quantum tunneling to zero size. In addition, we investigate the effect of vacuum corrections, due to the trace anomaly and the Casimir effect, on the stability of an oscillating universe with respect to decay by tunneling to the singularity. We find that these corrections do not generally stabilize an oscillating universe. Finally, we determine the decay rate of the oscillating universe. Although the wave function of the universe lacks explicit time dependence in canonical quantum cosmology, time evolution may be present implicitly through the semiclassical superspace variables, which themselves depend on time in classical dynamics. Here, we apply this approach to the simple harmonic universe, by extending the model to include a massless, minimally coupled scalar field φ which has little effect on the dynamics but can play the role of a "clock''.

  11. A clean, bright, and versatile source of neutron decay products

    NASA Astrophysics Data System (ADS)

    Dubbers, D.; Abele, H.; Baeßler, S.; Märkisch, B.; Schumann, M.; Soldner, T.; Zimmer, O.

    2008-11-01

    We present a case study on a new type of beam station for the measurement of angular correlations in the β-decay of free neutrons. This beam station, called proton and electron radiation channel (PERC), is a cold-neutron guide that delivers at its open end, instead of neutrons, a beam of electrons and protons from neutron decays that take place far inside the guide. These charged neutron-decay products are magnetically guided to the end of the neutron guide, where they are separated from the cold-neutron beam. In this way, a general-purpose source of neutron decay products is obtained which can be operated as a user facility for a variety of different experiments in neutron decay correlation spectroscopy that may be installed at this beam station. The angular distribution of the emitted charged particles depends on the magnetic field configuration and can be chosen freely, according to the need of the experiment being carried out. A gain in phase space density of several orders of magnitude can be achieved with PERC, as compared to existing neutron decay spectrometers. Detailed calculations show that the spectra and angular distributions of the emerging electrons and protons will be distortion- and background-free on the level of 10 -4, more than 10 times better than that achieved today.

  12. Gravitino decay and the cosmic gamma-ray background

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.

    1986-01-01

    It is argued that the cosmic gamma-ray background (CGB) spectrum does not exhibit evidence for the decay of light gravitinos, in contradiction to the suggestion by Olive and Silk (1985), who observed a bump near 1 MeV in the CGB radiation spectrum. It is suggested that better fits to the CGB spectrum would be provided by mechanisms generating a power-law spectrum which is flattened below about 2 MeV. Olive and Silk maintain that the decays of a long-lived particle such as the gravitino may be responsible for features in the gamma-ray spectrum near 1 MeV.

  13. Counterflow driven by swirl decay

    NASA Astrophysics Data System (ADS)

    Shtern, Vladimir N.; Borissov, Anatoli A.

    2010-06-01

    The global meridional circulation of a viscous fluid, caused by swirl decay in a cylindrical container, is studied. To this end, a new solution to the Navier-Stokes equations is obtained, and simple experiments are performed to verify the predictions of the theory. The swirl decay mechanism explains elongated counterflows in hydrocyclones and vortex tubes sometimes extending over a hundred diameters.

  14. Status of rare decay experiments

    SciTech Connect

    Littenberg, L.S.

    1984-01-01

    Some results are given for rare muon decay experiments currently running. Also, plans are discussed for rare kaon decay experiments. Some of the events sought come from processes which violate lepton flavor conservation. Several apparatuses used in the search are described. 35 references. (LEW)

  15. Particle decay in inflationary cosmology

    SciTech Connect

    Boyanovsky, D.; Vega, H.J. de

    2004-09-15

    We investigate the relaxation and decay of a particle during inflation by implementing the dynamical renormalization group. This investigation allows us to give a meaningful definition for the decay rate in an expanding universe. As a prelude to a more general scenario, the method is applied here to study the decay of a particle in de Sitter inflation via a trilinear coupling to massless conformally coupled particles, both for wavelengths much larger and much smaller than the Hubble radius. For superhorizon modes we find that the decay is of the form {eta}{sup {gamma}{sub 1}} with {eta} being conformal time and we give an explicit expression for {gamma}{sub 1} to leading order in the coupling which has a noteworthy interpretation in terms of the Hawking temperature of de Sitter space-time. We show that if the mass M of the decaying field is <decay rate during inflation is enhanced over the Minkowski space-time result by a factor 2H/{pi}M. For wavelengths much smaller than the Hubble radius we find that the decay law is e with C({eta}) the scale factor and {alpha} determined by the strength of the trilinear coupling. In all cases we find a substantial enhancement in the decay law as compared to Minkowski space-time. These results suggest potential implications for the spectrum of scalar density fluctuations as well as non-Gaussianities.

  16. Radiative and Electroweak Penguins at Belle

    NASA Astrophysics Data System (ADS)

    Hyun, HyoJung

    2010-02-01

    Radiative and electroweak penguin decays of B mesons are a sensitive probe of new physics beyond the Standard Model. We study the inclusive and exclusive radiative and electroweak penguin decays of B meson and also search an exotic particle seen by the HyperCP experiment. The measurements are based on a large data sample of 605 fb-1 containing 657 millions BB¯ pairs collected at the Υ(4S) with the Belle detector at the KEKB energy asymmetric e+e- collider.

  17. Spectral decomposition of phosphorescence decays.

    PubMed

    Fuhrmann, N; Brübach, J; Dreizler, A

    2013-11-01

    In phosphor thermometry, the fitting of decay curves is a key task in the robust and precise determination of temperatures. These decays are generally assumed to be mono-exponential in certain temporal boundaries, where fitting is performed. The present study suggests a multi-exponential method to determine the spectral distribution in terms of decay times in order to analyze phosphorescence decays and thereby complement the mono-exponential analysis. Therefore, two methods of choice are compared and verified using simulated data in the presence of noise. Addtionally, this spectral decomposition is applied to the thermographic phosphor Mg4FGeO6 : Mn and reveals changes in the exponential distributions of decay times upon a change of the excitation laser energy.

  18. Fine structure of cluster decays

    SciTech Connect

    Dumitrescu, O.

    1994-03-01

    Within the one level {ital R}-matrix approach, expressions are derived for the hindrance factors of cluster radioactive decays in which {ital y} {ital the} {ital shell} {ital model} {ital with} {ital effective} {ital residual} {ital interactions} [{ital e}.{ital g}.,{ital thelar} in the Michigan State University version for nearly spherical nuclei, or the enlarged superfluid model (ESM) recently proposed for deformed nuclei]. The exterior wave functions are calculated from a cluster-nucleus double-folding model potential obtained with the M3Y interaction. As examples of the cluster decay fine structure we analyzed the particular cases of {alpha} decay of {sup 241}Am and {sup 243}Cm, {sup 14}C decay of {sup 223}Ra, and {sup 34}Si decay of {sup 243}Cm. Good agreement with the experimental data is obtained.

  19. Primordial nucleosynthesis with decaying particles. I - Entropy-producing decays. II - Inert decays

    NASA Technical Reports Server (NTRS)

    Scherrer, Robert J.; Turner, Michael S.

    1988-01-01

    The effect of a nonrelativistic particle X, which decays out of equilibrium, on primordial nucleosynthesis is investigated, including both the energy density of the X particle and the electromagnetic entropy production from its decay. The results are parametrized in terms of the X particle lifetime and the density parameter rm(X), where m(X) is the X particle mass and r is the ratio of X number density to photon number density prior to nucleosynthesis. The results rule out particle lifetimes greater than 1-10 s for large values of rm(X). The question of a decaying particle which produces no electromagnetic entropy in the course of its decay is addressed, and particles which produce both entropy and an inert component in their decay are discussed.

  20. Decay of H atoms excited in small electric fields

    SciTech Connect

    Van Zyl, B.; Van Zyl, B.K.; Westerveld, W.B.

    1988-06-01

    The branching ratios for radiative decay of H atoms excited in small electric fields (0--5 Vcm) have been calculated for the nl states up to n = 6. A simple computational procedure was employed, allowing only for Stark-effect mixing of levels with the same values of the quantum numbers (n,j,m/sub j/). The results are compared with more detailed calculations available for 3l-state decay made using the density-matrix formalism, and new calculations of this type reported here for 4l-state decay. In conjunction with theory, this allowed the domain of validity of the simple computational procedure to be established as a function of n. The results show that the branching ratios depend quite strongly on electric-field magnitude, pointing to the need to exercise caution in measurements of H emissions, and in application of the available data to other problems.

  1. Optimizing VANDLE for Decay Spectroscopy

    NASA Astrophysics Data System (ADS)

    Brewer, N. T.; Taylor, S. Z.; Grzywacz, R.; Madurga, M.; Paulauskas, S. V.; Cizewski, J. A.; Peters, W. A.; Vandle Collaboration

    2013-10-01

    Understanding the decay properties of neutron rich isotopes has well established importance to the path of the r-process and to the total decay heat for reactor physics. Specifically, the half-life, branching ratio and spectra for β-n decay is of particular interest. With that in mind, we have continued attempts to improve upon the Versatile Array of Neutron Detectors at Low Energy (VANDLE) in terms of efficiency and TOF resolution through the use of new and larger scintillators. Details of the new implementation, design and characterization of the array will be shown and compared to previous results.

  2. Radiation Effects on the Sorption and Mobilization of Radionuclide during Transport through the Geosphere

    SciTech Connect

    L.M. Wang; R.C. Eqing; K.F. Hayes

    2004-03-14

    Site restoration activities at DOE facilities and the permanent disposal of nuclear waste inevitably involve understanding the behavior of materials in a radiation field. Radionuclide decay and the associated radiation fields lead to physical and chemical changes that can degrade or enhance important material properties. Alpha-decay of the actinide elements and beta-decay of the fission products lead to atomic-scale changes in materials (radiation damage and transmutation).

  3. Virus decay and its causes in coastal waters.

    PubMed

    Noble, R T; Fuhrman, J A

    1997-01-01

    Recent evidence suggests that viruses play an influential role within the marine microbial food web. To understand this role, it is important to determine rates and mechanisms of virus removal and degradation. We used plaque assays to examine the decay of infectivity in lab-grown viruses seeded into natural seawater. The rates of loss of infectivity of native viruses from Santa Monica Bay and of nonnative viruses from the North Sea in the coastal seawater of Santa Monica Bay were determined. Viruses were seeded into fresh seawater that had been pretreated in various ways: filtration with a 0.2-(mu)m-pore-size filter to remove organisms, heat to denature enzymes, and dissolved organic matter enrichment to reconstitute enzyme activity. Seawater samples were then incubated in full sunlight, in the dark, or under glass to allow partitioning of causative agents of virus decay. Solar radiation always resulted in increased rates of loss of virus infectivity. Virus isolates which are native to Santa Monica Bay consistently degraded more slowly in full sunlight in untreated seawater (decay ranged from 4.1 to 7.2% h(sup-1)) than nonnative marine bacteriophages which were isolated from the North Sea (decay ranged from 6.6 to 11.1% h(sup-1)). All phages demonstrated susceptibility to degradation by heat-labile substances, as heat treatment reduced the decay rates to about 0.5 to 2.0% h(sup-1) in the dark. Filtration reduced decay rates by various amounts, averaging 20%. Heat-labile, high-molecular-weight dissolved material (>30 kDa, probably enzymes) appeared responsible for about 1/5 of the maximal decay. Solar radiation was responsible for about 1/3 to 2/3 of the maximal decay of nonnative viruses and about 1/4 to 1/3 of that of the native viruses, suggesting evolutionary adaptation to local light levels. Our results suggest that sunlight is an important contributing factor to virus decay but also point to the significance of particles and dissolved substances in seawater.

  4. Virus decay and its causes in coastal waters.

    PubMed

    Noble, R T; Fuhrman, J A

    1997-01-01

    Recent evidence suggests that viruses play an influential role within the marine microbial food web. To understand this role, it is important to determine rates and mechanisms of virus removal and degradation. We used plaque assays to examine the decay of infectivity in lab-grown viruses seeded into natural seawater. The rates of loss of infectivity of native viruses from Santa Monica Bay and of nonnative viruses from the North Sea in the coastal seawater of Santa Monica Bay were determined. Viruses were seeded into fresh seawater that had been pretreated in various ways: filtration with a 0.2-(mu)m-pore-size filter to remove organisms, heat to denature enzymes, and dissolved organic matter enrichment to reconstitute enzyme activity. Seawater samples were then incubated in full sunlight, in the dark, or under glass to allow partitioning of causative agents of virus decay. Solar radiation always resulted in increased rates of loss of virus infectivity. Virus isolates which are native to Santa Monica Bay consistently degraded more slowly in full sunlight in untreated seawater (decay ranged from 4.1 to 7.2% h(sup-1)) than nonnative marine bacteriophages which were isolated from the North Sea (decay ranged from 6.6 to 11.1% h(sup-1)). All phages demonstrated susceptibility to degradation by heat-labile substances, as heat treatment reduced the decay rates to about 0.5 to 2.0% h(sup-1) in the dark. Filtration reduced decay rates by various amounts, averaging 20%. Heat-labile, high-molecular-weight dissolved material (>30 kDa, probably enzymes) appeared responsible for about 1/5 of the maximal decay. Solar radiation was responsible for about 1/3 to 2/3 of the maximal decay of nonnative viruses and about 1/4 to 1/3 of that of the native viruses, suggesting evolutionary adaptation to local light levels. Our results suggest that sunlight is an important contributing factor to virus decay but also point to the significance of particles and dissolved substances in seawater

  5. CP violation in K decays

    SciTech Connect

    Gilman, F.J.

    1989-05-01

    Recent theoretical and experimental progress on the manifestation of CP violation in K decays, and toward understanding whether CP violation originates in a phase, or phases, in the weak mixing matrix of quarks is reviewed. 23 refs., 10 figs.

  6. The Search for Proton Decay.

    ERIC Educational Resources Information Center

    Marshak, Marvin L.

    1984-01-01

    Provides the rationale for and examples of experiments designed to test the stability of protons and bound neutrons. Also considers the unification question, cosmological implications, current and future detectors, and current status of knowledge on proton decay. (JN)

  7. Questions Students Ask: Beta Decay.

    ERIC Educational Resources Information Center

    Koss, Jordan; Hartt, Kenneth

    1988-01-01

    Answers a student's question about the emission of a positron from a nucleus. Discusses the problem from the aspects of the uncertainty principle, beta decay, the Fermi Theory, and modern physics. (YP)

  8. Dark radiation from modulated reheating

    SciTech Connect

    Kobayashi, Takeshi; Takahashi, Fuminobu; Takahashi, Tomo; Yamaguchi, Masahide E-mail: fumi@tuhep.phys.tohoku.ac.jp E-mail: gucci@phys.titech.ac.jp

    2012-03-01

    We show that the modulated reheating mechanism can naturally account for dark radiation, whose existence is hinted by recent observations of the cosmic microwave background radiation and the primordial Helium abundance. In this mechanism, the inflaton decay rate depends on a light modulus which acquires almost scale-invariant quantum fluctuations during inflation. We find that the light modulus is generically produced by the inflaton decay and therefore a prime candidate for the dark radiation. Interestingly, an almost scale-invariant power spectrum predicted in the modulated reheating mechanism gives a better fit to the observation in the presence of the extra radiation. We discuss the production mechanism of the light modulus in detail taking account of its associated isocurvature fluctuations. We also consider a case where the modulus becomes the dominant component of dark matter.

  9. Lorentz violation and {alpha} decay

    SciTech Connect

    Altschul, Brett

    2009-01-01

    Relating the effective Lorentz violation coefficients for composite particles to the coefficients for their constituent fields is a challenging problem. We calculate the Lorentz violation coefficients relevant to the dynamics of an {alpha} particle in terms of proton and neutron coefficients. The {alpha}-particle coefficients would lead to anisotropies in the {alpha} decays of nuclei, and because the decay process involves quantum tunneling, the effects of any Lorentz violations could be exponentially enhanced.

  10. Reionization and dark matter decay

    NASA Astrophysics Data System (ADS)

    Oldengott, Isabel M.; Boriero, Daniel; Schwarz, Dominik J.

    2016-08-01

    Cosmic reionization and dark matter decay can impact observations of the cosmic microwave sky in a similar way. A simultaneous study of both effects is required to constrain unstable dark matter from cosmic microwave background observations. We compare two reionization models with and without dark matter decay. We find that a reionization model that fits also data from quasars and star forming galaxies results in tighter constraints on the reionization optical depth τreio, but weaker constraints on the spectral index ns than the conventional parametrization. We use the Planck 2015 data to constrain the effective decay rate of dark matter to Γeff < 2.9 × 10-25/s at 95% C.L. This limit is robust and model independent. It holds for any type of decaying dark matter and it depends only weakly on the chosen parametrization of astrophysical reionization. For light dark matter particles that decay exclusively into electromagnetic components this implies a limit of Γ < 5.3 × 10-26/s at 95% C.L. Specifying the decay channels, we apply our result to the case of keV-mass sterile neutrinos as dark matter candidates and obtain constraints on their mixing angle and mass, which are comparable to the ones from the diffuse X-ray background.

  11. Reionization and dark matter decay

    NASA Astrophysics Data System (ADS)

    Oldengott, Isabel M.; Boriero, Daniel; Schwarz, Dominik J.

    2016-08-01

    Cosmic reionization and dark matter decay can impact observations of the cosmic microwave sky in a similar way. A simultaneous study of both effects is required to constrain unstable dark matter from cosmic microwave background observations. We compare two reionization models with and without dark matter decay. We find that a reionization model that fits also data from quasars and star forming galaxies results in tighter constraints on the reionization optical depth τreio, but weaker constraints on the spectral index ns than the conventional parametrization. We use the Planck 2015 data to constrain the effective decay rate of dark matter to Γeff < 2.9 × 10‑25/s at 95% C.L. This limit is robust and model independent. It holds for any type of decaying dark matter and it depends only weakly on the chosen parametrization of astrophysical reionization. For light dark matter particles that decay exclusively into electromagnetic components this implies a limit of Γ < 5.3 × 10‑26/s at 95% C.L. Specifying the decay channels, we apply our result to the case of keV-mass sterile neutrinos as dark matter candidates and obtain constraints on their mixing angle and mass, which are comparable to the ones from the diffuse X-ray background.

  12. Rare B-meson decays at the crossroads

    NASA Astrophysics Data System (ADS)

    Ali, Ahmed

    2016-08-01

    Experimental era of rare B-decays started with the measurement of B → K∗γ by CLEO in 1993, followed by the measurement of the inclusive decay B → Xsγ in 1995, which serves as the standard candle in this field. The frontier has moved in the meanwhile to the experiments at the LHC, in particular, LHCb, with the decay B0 → μ+μ- at about 1 part in 1010 being the smallest branching fraction measured so far. Experimental precision achieved in this area has put the standard model to unprecedented stringent tests and more are in the offing in the near future. I review some key measurements in radiative, semileptonic and leptonic rare B-decays, contrast them with their estimates in the SM, and focus on several mismatches reported recently. They are too numerous to be ignored, yet, standing alone, none of them is significant enough to warrant the breakdown of the SM. Rare B-decays find themselves at the crossroads, possibly pointing to new horizons, but quite likely requiring an improved theoretical description in the context of the SM. An independent precision experiment such as Belle II may help greatly in clearing some of the current experimental issues.

  13. Rare B-meson decays at the crossroads

    NASA Astrophysics Data System (ADS)

    Ali, Ahmed

    2016-08-01

    Experimental era of rare B-decays started with the measurement of B → K∗γ by CLEO in 1993, followed by the measurement of the inclusive decay B → Xsγ in 1995, which serves as the standard candle in this field. The frontier has moved in the meanwhile to the experiments at the LHC, in particular, LHCb, with the decay B0 → μ+μ‑ at about 1 part in 1010 being the smallest branching fraction measured so far. Experimental precision achieved in this area has put the standard model to unprecedented stringent tests and more are in the offing in the near future. I review some key measurements in radiative, semileptonic and leptonic rare B-decays, contrast them with their estimates in the SM, and focus on several mismatches reported recently. They are too numerous to be ignored, yet, standing alone, none of them is significant enough to warrant the breakdown of the SM. Rare B-decays find themselves at the crossroads, possibly pointing to new horizons, but quite likely requiring an improved theoretical description in the context of the SM. An independent precision experiment such as Belle II may help greatly in clearing some of the current experimental issues.

  14. A model for multiexponential tryptophan fluorescence intensity decay in proteins.

    PubMed Central

    Bajzer, Z; Prendergast, F G

    1993-01-01

    Tryptophan fluorescence intensity decay in proteins is modeled by multiexponential functions characterized by lifetimes and preexponential factors. Commonly, multiple conformations of the protein are invoked to explain the recovery of two or more lifetimes from the experimental data. However, in many proteins the structure seems to preclude the possibility of multiple conformers sufficiently different from one another to justify such an inference. We present here another plausible multiexponential model based on the assumption that an energetically excited donor surrounded by N acceptor molecules decays by specific radiative and radiationless relaxation processes, and by transferring its energy to acceptors present in or close to the protein matrix. If interactions between the acceptors themselves and back energy transfer are neglected, we show that the intensity decay function contain 2N exponential components characterized by the unperturbed donor lifetime, by energy transfer rates and a probability of occurrence for the corresponding process. We applied this model to the fluorescence decay of holo- and apoazurin, ribonuclease T1, and the reduced single tryptophan mutant (W28F) of thioredoxin. Use of a multiexponential model for the analysis of the fluorescence intensity decay can therefore be justified, without invoking multiple protein conformations. Images FIGURE 1 PMID:8312471

  15. Photoluminescence decay rate of silicon nanoparticles modified with gold nanoislands

    NASA Astrophysics Data System (ADS)

    Dan'ko, Viktor; Michailovska, Katerina; Indutnyi, Ivan; Shepeliavyi, Petro

    2014-04-01

    We investigated plasmon-assisted enhancement of emission from silicon nanoparticles (ncs-Si) embedded into porous SiO x matrix in the 500- to 820-nm wavelength range. In the presence in the near-surface region of gold nanoisland film, ncs-Si exhibited up to twofold luminescence enhancement at emission frequencies that correspond to the plasmon resonance frequency of Au nanoparticles. Enhancement of the photoluminescence (PL) intensity was attributed to coupling with the localized surface plasmons (LSPs) excited in Au nanoparticles and to increase in the radiative decay rate of ncs-Si . It has been shown that spontaneous emission decay rate of ncs-Si modified by thin Au film over the wide emission spectral range was accelerated. The emission decay rate distribution was determined by fitting the experimental decay curves to the stretched exponential model. The observed increase of the PL decay rate distribution width for the Au-coated nc-Si-SiO x sample in comparison with the uncoated one was explained by fluctuations in the surface-plasmon excitation rate .

  16. Bound muon decay spectrum in the leading logarithmic accuracy

    NASA Astrophysics Data System (ADS)

    Szafron, Robert; Czarnecki, Andrzej

    2016-09-01

    We compute the dominant, logarithmically enhanced radiative corrections to the electron spectrum in bound muon decay in the whole experimentally interesting range. The corrected spectrum fits well with the results from the TWIST Collaboration. The remaining theoretical error, dominated by the nuclear charge distribution, can be reduced in the muon-electron conversion searches by measuring the spectrum slightly below the new physics signal window.

  17. Nuclear decay data files of the Dosimetry Research Group

    SciTech Connect

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

    1993-12-01

    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.

  18. Radiative B Meson Decay as a Probe of Physics Beyond the Standard Model: Time-Dependent CP Violation in B0 → K0S π0 γ and the B → Φ K γ Branching Fraction

    SciTech Connect

    Joseph Marion Tuggle IV

    2009-01-01

    The author presents measurements of radiative B meson decays to the final states Ks0π0γ and KΦγ based on data collected at the Υ(4S) resonance with the BABAR detector at the PEP-II e+e- collider at SLAC. In a data sample of 467 million B$\\bar{B}$ pairs, the time-dependent CP asymmetry in B0 → Ks0π0γ decays is measured in two regions of Ks00 invariant mass. In the K* region, 0.8 < m(Ks0π0) < 1.0 GeV/c2, we find SK*γ = -0.03 ± 0.29 ± 0.03 and CK*γ = -0.14 ± 0.16 ± 0.03; in the range 1.1 < m(Ks0π0) < 1.8 GeV/c2, they find SKs0π0γ = -0.78 ± 0.59 ± 0.09 and C Ks0π0γ = -0.36 ± 0.33 ± 0.04. With a sample of 228 million B$\\bar{B}$ pairs they measure the branching fraction β(B+ → K+Φγ) = (3.5 ± 0.6 ± 0.4) x 10-6 and set the limit β(B0→ K0Φγ) < 2.7 x 10-6 at 90% confidence level. The direct CP asymmetry in B+ → K+Φγ is found to be A CP = (-26 ±14 ± 5)%. In each case the uncertainties are statistical and systematic, respectively.

  19. MUON DECAY ASYMMETRIES FROM KOL YIELDS POM+M-DECAYS.

    SciTech Connect

    DIWAN, M.V.; MA, H.; TRUEMAN, T.L.

    2001-06-12

    We have examined the decay K{sub L}{sup 0} {yields} {pi}{sup 0} {mu}{sup +} {mu}{sup -} in which the branching ratio, the muon energy asymmetry and the muon decay asymmetry could be measured. In particular, we find that within the Standard Model the longitudinal polarization (PL) of the muon is proportional to the direct CP violating amplitude. On the other hand the energy asymmetry and the out-of-plane polarization (P{sub N}) depend on both indirect and direct CP violating amplitudes. Although the branching ratio is small and difficult to measure because of background, the asymmetries could be large {Omicron}(1) in the Standard Model. A combined analysis of the energy asymmetry, P{sub L} and P{sub N} could be used to separate indirect, CPV, direct CPV, and CP conserving contributions to the decay.

  20. Unsolved problems in hadronic charm decay

    SciTech Connect

    Browder, T.E.

    1989-08-01

    This paper describes several outstanding problems in the study of hadronic decays of charmed mesons where further experimental work and theoretical understanding is needed. Four topics are stressed: double Cabibbo suppressed decays (DCSD) of D/sup +/ mesons, hadronic D/sub s/ decays, weak hadronic quasi-two-body decays to pairs of vector mesons, and penguin decays of D mesons. 24 refs., 10 figs., 5 tabs.

  1. Decay curve study in a standard electron capture decay

    SciTech Connect

    Nishimura, D.; Fukuda, M.; Kisamori, K.; Kuwada, Y.; Makisaka, K.; Matsumiya, R.; Matsuta, K.; Mihara, M.; Takagi, A.; Yokoyama, R.; Izumikawa, T.; Ohtsubo, T.; Suzuki, T.; Yamaguchi, T.

    2010-05-12

    We have searched for a time-modulated decay in a standard electron capture experiment for {sup 140}Pr, in order to confirm a report from GSI, where an oscillatory decay has been observed for hydrogen-like {sup 140}Pr and {sup 142}Pm ions in the cooler storage ring. {sup 140}Pr has been produced with the {sup 140}Ce(p, n) reaction by a pulsed proton beam accelerated from the Van de Graaff accelerator at Osaka University. Resultant time dependence of the K{sub a}lpha and K{sub b}eta X-ray intensities from the daughter shows no oscillatory behavior.

  2. Heavy quark spectroscopy and decay

    SciTech Connect

    Schindler, R.H.

    1987-01-01

    The understanding of q anti q systems containing heavy, charmed, and bottom quarks has progressed rapidly in recent years, through steady improvements in experimental techniques for production and detection of their decays. These lectures are meant to be an experimentalist's review of the subject. In the first of two lectures, the existing data on the spectroscopy of the bound c anti c and b anti b systems will be discussed. Emphasis is placed on comparisons with the theoretical models. The second lecture covers the rapidly changing subject of the decays of heavy mesons (c anti q and b anti q), and their excited states. In combination, the spectroscopy and decays of heavy quarks are shown to provide interesting insights into both the strong and electroweak interactions of the heavy quarks. 103 refs., 39 figs.

  3. Decay of capillary wave turbulence.

    PubMed

    Deike, Luc; Berhanu, Michael; Falcon, Eric

    2012-06-01

    We report on the observation of freely decaying capillary wave turbulence on the surface of a fluid. The capillary wave turbulence spectrum decay is found to be self-similar in time with the same power law exponent as the one found in the stationary regime, in agreement with weak turbulence predictions. The amplitude of all Fourier modes are found to decrease exponentially with time at the same damping rate. The longest wavelengths involved in the system are shown to be damped by a viscous surface boundary layer. These long waves play the role of an energy source during the decay that sustains nonlinear interactions to keep capillary waves in a wave turbulent state.

  4. Two surface plasmon decay of plasma oscillations

    SciTech Connect

    Kluge, T. Metzkes, J.; Zeil, K.; Bussmann, M.; Schramm, U.; Cowan, T. E.

    2015-06-15

    The interaction of ultra-intense lasers with solid foils can be used to accelerate ions to high energies well exceeding 60 MeV [Gaillard et al., Phys. Plasmas 18, 056710 (2011)]. The non-linear relativistic motion of electrons in the intense laser radiation leads to their acceleration and later to the acceleration of ions. Ions can be accelerated from the front surface, the foil interior region, and the foil rear surface (target normal sheath acceleration (TNSA), most widely used), or the foil may be accelerated as a whole if sufficiently thin (radiation pressure acceleration). Here, we focus on the most widely used mechanism for laser ion-acceleration of TNSA. Starting from perfectly flat foils, we show by simulations how electron filamentation at or inside the solid leads to spatial modulations in the ions. The exact dynamics depend very sensitively on the chosen initial parameters which has a tremendous effect on electron dynamics. In the case of step-like density gradients, we find evidence that suggests a two-surface-plasmon decay of plasma oscillations triggering a Raileigh-Taylor-like instability.

  5. Gamma-ray lines from novae. [relationship to radioactive decay and positron annihilation

    NASA Technical Reports Server (NTRS)

    Clayton, D. D.; Hoyle, F.

    1974-01-01

    An appropriate gamma-ray telescope could detect the gamma-rays associated with radioactive decays. The observable lines would be the annihilation radiation following the positron emission of N-13, O-14, O-15, and Na-22 and the 2.312-MeV line emitted following the O-14 decay and the 1.274-MeV line emitted following the Na-22 decay. The experimental possibility should be borne in mind for the occurrence of novae within a few kiloparsecs.

  6. Decay of dark and bright plasmonic modes in a metallic nanoparticle dimer

    NASA Astrophysics Data System (ADS)

    Brandstetter-Kunc, Adam; Weick, Guillaume; Weinmann, Dietmar; Jalabert, Rodolfo A.

    2015-01-01

    We develop a general quantum theory of the coupled plasmonic modes resulting from the near-field interaction between localized surface plasmons in a heterogeneous metallic nanoparticle dimer. In particular, we provide analytical expressions for the frequencies and decay rates of the bright and dark plasmonic modes. We show that, for sufficiently small nanoparticles, the main decay channel for the dark plasmonic mode, which is weakly coupled to light and, hence, immune to radiation damping, is of nonradiative origin and corresponds to Landau damping, i.e., decay into electron-hole pairs.

  7. Radiation enteritis

    MedlinePlus

    Radiation enteropathy; Radiation-induced small bowel injury; Post-radiation enteritis ... Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells. The therapy ...

  8. β decay of Na32

    NASA Astrophysics Data System (ADS)

    Mattoon, C. M.; Sarazin, F.; Hackman, G.; Cunningham, E. S.; Austin, R. A. E.; Ball, G. C.; Chakrawarthy, R. S.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hyland, B.; Koopmans, K. A.; Leslie, J. R.; Phillips, A. A.; Schumaker, M. A.; Scraggs, H. C.; Schwarzenberg, J.; Smith, M. B.; Svensson, C. E.; Waddington, J. C.; Walker, P. M.; Washbrook, B.; Zganjar, E.

    2007-01-01

    The β-decay of Na32 has been studied using β-γ coincidences. New transitions and levels are tentatively placed in the level scheme of Mg32 from an analysis of γ-γ and β-γ-γ coincidences. The observation of the indirect feeding of the 2321 keV state in Mg32 removes some restrictions previously placed on the spin assignment for this state. No evidence of a state at 2117 keV in Mg32 is found. Previously unobserved weak transitions up to 5.4 MeV were recorded but could not be placed in the decay scheme of Na32.

  9. Laser-Assisted Muon Decay

    SciTech Connect

    Liu Aihua; Li Shumin; Berakdar, Jamal

    2007-06-22

    We show theoretically that the muon lifetime can be changed dramatically by embedding the decaying muon in a strong linearly polarized laser field. Evaluating the S-matrix elements taking all electronic multiphoton processes into account we find that a CO{sub 2} laser with an electric field amplitude of 10{sup 6} V cm{sup -1} results in an order of magnitude shorter lifetime of the muon. We also analyze the dependencies of the decay rate on the laser frequency and intensity.

  10. Decay Data Evaluation Project (DDEP): evaluation of the main 233Pa decay characteristics.

    PubMed

    Chechev, Valery P; Kuzmenko, Nikolay K

    2006-01-01

    The results of a decay data evaluation are presented for 233Pa (beta-) decay to nuclear levels in 233U. These evaluated data have been obtained within the Decay Data Evaluation Project using information published up to 2005.

  11. Decay Data Evaluation Project (DDEP): evaluation of the main 233Pa decay characteristics.

    PubMed

    Chechev, Valery P; Kuzmenko, Nikolay K

    2006-01-01

    The results of a decay data evaluation are presented for 233Pa (beta-) decay to nuclear levels in 233U. These evaluated data have been obtained within the Decay Data Evaluation Project using information published up to 2005. PMID:16574422

  12. Multiple photon emission in heavy particle decays

    NASA Technical Reports Server (NTRS)

    Asakimori, K.; Burnett, T. H.; Cherry, M. L.; Christl, M. J.; Dake, S.; Derrickson, J. H.; Fountain, W. F.; Fuki, M.; Gregory, J. C.; Hayashi, T.

    1994-01-01

    Cosmic ray interactions, at energies above 1 TeV/nucleon, in emulsion chambers flown on high altitude balloons have yielded two events showing apparent decays of a heavy particle into one charged particle and four photons. The photons converted into electron pairs very close to the decay vertex. Attempts to explain this decay topology with known particle decays are presented. Unless both events represent a b yields u transition, which is statistically unlikely, then other known decay modes for charmed or bottom particles do not account satisfactorily for these observations. This could indicate, possibly, a new decay channel.

  13. CP violation and rare decays

    SciTech Connect

    Quigg, C.

    2000-01-24

    After a brief essay on the current state of particle physics and possible approaches to the opportunities that have presented themselves, the author summarizes the contributions to the Third Workshop on Physics and Detectors for DA{Phi}NE that deal with CP Violation and Rare Decays.

  14. Rare decays at the Tevatron

    SciTech Connect

    Farrington, S.M.; /Liverpool U.

    2006-01-01

    The confidence level limits of the CDF and D0 searches for the B{sub s}{sup 0}, B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -} and B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}{phi} rare decays are presented.

  15. First observation of the decay

    NASA Astrophysics Data System (ADS)

    Aaij, R.; Abellan Beteta, C.; Adeva, B.; Adinolfi, M.; Adrover, C.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, R.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Bachmann, S.; Back, J. J.; Baesso, C.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Benayoun, M.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Burducea, I.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Campora Perez, D.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Charles, M.; Charpentier, Ph.; Chen, P.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; David, P.; David, P. N. Y.; Davis, A.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Dogaru, M.; Donleavy, S.; Dordei, F.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; van Eijk, D.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Elsby, D.; Falabella, A.; Färber, C.; Fardell, G.; Farinelli, C.; Farry, S.; Fave, V.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furcas, S.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Garosi, P.; Garra Tico, J.; Garrido, L.; Gaspar, C.; Gauld, R.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gibson, V.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J. A.; van Herwijnen, E.; Hicheur, A.; Hicks, E.; Hill, D.; Hoballah, M.; Holtrop, M.; Hombach, C.; Hopchev, P.; Hulsbergen, W.; Hunt, P.; Huse, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jans, E.; Jaton, P.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Kaballo, M.; Kandybei, S.; Karacson, M.; Karbach, T. M.; Kenyon, I. R.; Kerzel, U.; Ketel, T.; Keune, A.; Khanji, B.; Kochebina, O.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Li Gioi, L.; Liles, M.; Lindner, R.; Linn, C.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lopez Asamar, E.; Lopez-March, N.; Lu, H.; Lucchesi, D.; Luisier, J.; Luo, H.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Malde, S.; Manca, G.; Mancinelli, G.; Marconi, U.; Märki, R.; Marks, J.; Martellotti, G.; Martens, A.; Martín Sánchez, A.; Martinelli, M.; Martinez Santos, D.; Martins Tostes, D.; Massafferri, A.; Matev, R.; Mathe, Z.; Matteuzzi, C.; Maurice, E.; Mazurov, A.; McCarthy, J.; McNab, A.; McNulty, R.; Meadows, B.; Meier, F.; Meissner, M.; Merk, M.; Milanes, D. A.; Minard, M.-N.; Molina Rodriguez, J.; Monteil, S.; Moran, D.; Morawski, P.; Morello, M. J.; Mountain, R.; Mous, I.; Muheim, F.; Müller, K.; Muresan, R.; Muryn, B.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nasteva, I.; Needham, M.; Neufeld, N.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Nicol, M.; Niess, V.; Niet, R.; Nikitin, N.; Nikodem, T.; Nomerotski, A.; Novoselov, A.; Oblakowska-Mucha, A.; Obraztsov, V.; Oggero, S.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Orlandea, M.; Otalora Goicochea, J. M.; Owen, P.; Oyanguren, A.; Pal, B. K.; Palano, A.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Parkes, C.; Parkinson, C. J.; Passaleva, G.; Patel, G. D.; Patel, M.; Patrick, G. N.; Patrignani, C.; Pavel-Nicorescu, C.; Pazos Alvarez, A.; Pellegrino, A.; Penso, G.; Pepe Altarelli, M.; Perazzini, S.; Perego, D. L.; Perez Trigo, E.; Pérez-Calero Yzquierdo, A.; Perret, P.; Perrin-Terrin, M.; Pessina, G.; Petridis, K.; Petrolini, A.; Phan, A.; Picatoste Olloqui, E.; Pietrzyk, B.; Pilař, T.; Pinci, D.; Playfer, S.; Plo Casasus, M.; Polci, F.; Polok, G.; Poluektov, A.; Polycarpo, E.; Popov, D.; Popovici, B.; Potterat, C.; Powell, A.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Puig Navarro, A.; Punzi, G.; Qian, W.; Rademacker, J. H.; Rakotomiaramanana, B.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Redford, S.; Reid, M. M.; dos Reis, A. C.; Ricciardi, S.; Richards, A.; Rinnert, K.; Rives Molina, V.; Roa Romero, D. A.; Robbe, P.; Rodrigues, E.; Rodriguez Perez, P.; Roiser, S.; Romanovsky, V.; Romero Vidal, A.; Rouvinet, J.; Ruf, T.; Ruffini, F.; Ruiz, H.; Ruiz Valls, P.; Sabatino, G.; Saborido Silva, J. J.; Sagidova, N.; Sail, P.; Saitta, B.; Salzmann, C.; Sanmartin Sedes, B.; Sannino, M.; Santacesaria, R.; Santamarina Rios, C.; Santovetti, E.; Sapunov, M.; Sarti, A.; Satriano, C.; Satta, A.; Savrie, M.; Savrina, D.; Schaack, P.; Schiller, M.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmidt, B.; Schneider, O.; Schopper, A.; Schune, M.-H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Seco, M.; Semennikov, A.; Sepp, I.; Serra, N.; Serrano, J.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shatalov, P.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, O.; Shevchenko, V.; Shires, A.; Silva Coutinho, R.; Skwarnicki, T.; Smith, N. A.; Smith, E.; Smith, M.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; Souza, D.; De Paula, B. Souza; Spaan, B.; Sparkes, A.; Spradlin, P.; Stagni, F.; Stahl, S.; Steinkamp, O.; Stoica, S.; Stone, S.; Storaci, B.; Straticiuc, M.; Straumann, U.; Subbiah, V. K.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szczypka, P.; Szumlak, T.; T'Jampens, S.; Teklishyn, M.; Teodorescu, E.; Teubert, F.; Thomas, C.; Thomas, E.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Tolk, S.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Tran, M. T.; Tresch, M.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Ubeda Garcia, M.; Ukleja, A.; Urner, D.; Uwer, U.; Vagnoni, V.; Valenti, G.; Vazquez Gomez, R.; Vazquez Regueiro, P.; Vecchi, S.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; Voss, H.; Waldi, R.; Wallace, R.; Wandernoth, S.; Wang, J.; Ward, D. R.; Watson, N. K.; Webber, A. D.; Websdale, D.; Whitehead, M.; Wicht, J.; Wiechczynski, J.; Wiedner, D.; Wiggers, L.; Wilkinson, G.; Williams, M. P.; Williams, M.; Wilson, F. F.; Wishahi, J.; Witek, M.; Wotton, S. A.; Wright, S.; Wu, S.; Wyllie, K.; Xie, Y.; Xing, Z.; Yang, Z.; Young, R.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, F.; Zhang, L.; Zhang, W. C.; Zhang, Y.; Zhelezov, A.; Zhokhov, A.; Zhong, L.; Zvyagin, A.

    2013-11-01

    The first observation of the decay is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 fb-1 of pp collisions at TeV, collected with the LHCb detector. A yield of 30 ± 6 decays is found in the mass windows 1012.5 < M ( K + K -) < 1026.5 MeV/ c 2 and 746 < M( K - π +) < 1046 MeV/ c 2. The signal yield is found to be dominated by decays, and the corresponding branching fraction is measured to be = (1.10 ± 0.24 (stat) ± 0.14 (syst) ± 0.08 ( f d / f s )) × 10-6, where the uncertainties are statistical, systematic and from the ratio of fragmentation fractions f d / f s which accounts for the different production rate of B 0 and mesons. The significance of signal is 6.1 standard deviations. The fraction of longitudinal polarization in decays is found to be f 0 = 0.51 ± 0.15 (stat) ± 0.07 (syst). [Figure not available: see fulltext.

  16. Nuclear structure from radioactive decay

    SciTech Connect

    Wood, J.L.

    1990-09-30

    This report discusses the nuclear structure of the following isotopes as a result of radioactive decays: neutron-deficient iridium isotopes; neutron-deficient platinum isotopes; neutron-deficient gold isotopes; neutron-deficient mercury isotopes; neutron-deficient thallium isotopes; neutron-deficient lead isotopes; neutron-deficient promethium isotopes; and neutron-deficient samarium isotopes.

  17. Rare B decays at CDF

    SciTech Connect

    Farrington, Sinead M.; /Liverpool U.

    2006-10-01

    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.

  18. Review of tau lepton decays

    SciTech Connect

    Stoker, D.P.

    1991-07-01

    Measurements of the {tau} decay modes are reviewed and compared with the predictions of the Standard Model. While the agreement is generally good, the status of the 1-prong puzzle'' remains controversial and a discrepancy between the measured leptonic branching fractions and the {tau} lifetime persists. Prospects for precision measurements at a Tau-Charm Factory are also reviewed. 20 refs., 2 tabs.

  19. Fermi's β-DECAY Theory

    NASA Astrophysics Data System (ADS)

    Yang, Chen Ning

    2013-05-01

    Throughout his lifetime Enrico Fermi (1901-1954) had considered his 1934 β-decay theory as his most important contribution to theoretical physics. E. Segrè (1905-1989) had vividly written about an episode at the inception of that paper:1...

  20. Factorization and dispersion relations for radiative leptonic B decay

    NASA Astrophysics Data System (ADS)

    Wang, Yu-Ming

    2016-09-01

    Applying the dispersion approach we compute perturbative QCD corrections to the power suppressed soft contribution of B → γℓν at leading twist. QCD factorization for the B → γ * form factors is demonstrated explicitly for the hard-collinear transverse polarized photon at one loop, with the aid of the method of regions. While the one-loop hard function is identical to the matching coefficient of the QCD weak current ūγ μ ⊥(1 - γ 5) b in soft-collinear effective theory, the jet function from integrating out the hard-collinear fluctuations differs from the corresponding one entering the factorization formula of B → γℓν, due to the appearance of an additional hard-collinear momentum mode. Furthermore, we evaluate the sub-leading power contribution to the B → γ form factors from the three-particle B-meson distribution amplitudes (DAs) at tree level, with the dispersion approach. The soft contribution to the B → γ form factors from the three-particle B-meson DAs is shown to be of the same power compared with the corresponding hard correction, in contrast to the two-particle counterparts. Numerically the next-to-leading-order QCD correction to the soft two-particle contribution in B → γ form factors will induce an approximately (10 ˜ 20)% shift to the tree-level contribution at λ B ( μ 0) = 354 MeV. Albeit of power suppression parametrically, the soft two-particle correction can decrease the leading power predictions for the B → γ form factors by an amount of (10 ˜ 30)% with the same value of λ B ( μ 0). Employing the phenomenological model of the three-particle B-meson DAs inspired by a QCD sum rule analysis, the three-particle contribution to the B → γ form factors is predicted to be of O (1%), at leading order in α s , with the default theory inputs. Finally, we explore theory constraints on the inverse moment of the leading-twist B-meson DA λ B from the recent Belle measurements of the partial branching fractions of B → γℓν, taking into account the newly computed contributions to the B → γ form factors at subleading power.

  1. Radiative decay engineering 3. Surface plasmon-coupled directional emission

    PubMed Central

    Lakowicz, Joseph R.

    2009-01-01

    A new method of fluorescence detection that promises to increase sensitivity by 20- to 1000-fold is described. This method will also decrease the contribution of sample autofluorescence to the detected signal. The method depends on the coupling of excited fluorophores with the surface plasmon resonance present in thin metal films, typically silver and gold. The phenomenon of surface plasmon-coupled emission (SPCE) occurs for fluorophores 20–250 nm from the metal surface, allowing detection of fluorophores over substantial distances beyond the metal–sample interface. SPCE depends on interactions of the excited fluorophore with the metal surface. This interaction is independent of the mode of excitation; that is, it does not require evanescent wave or surface-plasmon excitation. In a sense, SPCE is the inverse process of the surface plasmon resonance absorption of thin metal films. Importantly, SPCE occurs over a narrow angular distribution, converting normally isotropic emission into easily collected directional emission. Up to 50% of the emission from unoriented samples can be collected, much larger than typical fluorescence collection efficiencies near 1% or less. SPCE is due only to fluorophores near the metal surface and may be regarded as emission from the induced surface plasmons. Autofluorescence from more distal parts of the sample is decreased due to decreased coupling. SPCE is highly polarized and autofluorescence can be further decreased by collecting only the polarized component or only the light propagating with the appropriate angle. Examples showing how simple optical configurations can be used in diagnostics, sensing, or biotechnology applications are presented. Surface plasmon-coupled emission is likely to find widespread applications throughout the biosciences. PMID:14690679

  2. Dark matter from late invisible decays to and of gravitinos

    NASA Astrophysics Data System (ADS)

    Allahverdi, Rouzbeh; Dutta, Bhaskar; Queiroz, Farinaldo S.; Strigari, Louis E.; Wang, Mei-Yu

    2015-03-01

    In this work, we sift a simple supersymmetric framework of late invisible decays to and of the gravitino. We study a simple extension of the minimal supersymmetric standard model that includes isosinglet color-triplet superfields and a singlet superfield. We investigate two cases where the gravitino is the lightest supersymmetric particle or the next-to-lightest supersymmetric particle. The next-to-lightest supersymmetric particle decays into two dark matter candidates and has a long lifetime due to gravitationally suppressed interactions. However, because of the absence of any hadronic or electromagnetic products, it satisfies the tight bounds set by big bang nucleosynthesis and the cosmic microwave background. One or both of the dark matter candidates produced in invisible decays can contribute to the amount of dark radiation and suppress perturbations at scales that are being probed by the galaxy power spectrum and the Lyman-alpha forest data. We show that these constraints are satisfied in large regions of the parameter space and, as a result, the late invisible decays to and of the gravitino can be responsible for the entire dark matter relic abundance.

  3. FDCSUSYDecay: An MSSM decay package

    NASA Astrophysics Data System (ADS)

    Qi, Wei; Wang, Jian-xiong

    2007-08-01

    FDCSUSYDecay is a FORTRAN program package generated by FDC (Feynman Diagram Calculation) system fully automatically. It is dedicated to calculate at tree-level all the possible 2-body decays of SUSY and Higgs particles in the Minimal Supersymmetric extension of the Standard Model (MSSM). The format of its output files complies with SUSY Les Houches Accord and can be easily imported by other packages. Program summaryManuscript title:FDCSUSYDecay: An MSSM decay package Authors:Wei Qi, Jian-xiong Wang Program title:FDCSUSYDecay (Version 1.00) Catalogue identifier:ADYV_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADYV_v1_0.html Program obtainable from:CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions:Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.:22 008 No. of bytes in distributed program, including test data, etc.:622 751 Distribution format:tar.gz Programming language:FORTRAN 77 Operating system:Linux Keywords:SUSY decay, MSSM, FDC PACS:02.70.-c, 12.60.Jv Classification:11.1, 11.6 External routines:CERNLIB 2003 (or up) Nature of problem: This package can calculate all the possible SUSY particle and Higgs 2-body decay width and branch ratio at tree-level in the MSSM model. Solution method: By running FDC, the Feynman rules for the MSSM model are generated, all the decay widths are calculated analytically and corresponding FORTRAN codes are generated for this package. Running time: Less than 1 second for both high-scale and low-scale modes on a Pentium IV 2.4 GHz machine (512 MB memory).

  4. Natural circulation decay heat removal from an SP-100, 550 kWe power system for a lunar outpost

    NASA Technical Reports Server (NTRS)

    El-Genk, Mohamed S.; Xue, Huimin

    1992-01-01

    This research investigated the decay heat removal from the SP-100 reactor core of a 550-kWe power system for a lunar outpost by natural circulation of lithium coolant. A transient model that simulates the decay heat removal loop (DHRL) of the power system was developed and used to assess the system's decay heat removal capability. The effects of the surface area of the decay heat rejection radiator, the dimensions of the decay heat exchanger (DHE) flow duct, the elevation of the DHE, and the diameter of the rise and down pipes in the DHRL on the decay heat removal capability were examined. Also, to determine the applicability of test results at earth gravity to actual system performance on the lunar surface, the effect of the gravity constant (1 g and 1/6 g) on the thermal behavior of the system after shutdown was investigated.

  5. Side Effects of Chemotherapy and Radiation (For Parents)

    MedlinePlus

    ... interact with the chemo drugs. Mouth, Gum, and Throat Sores Both chemo and radiation (specifically to the ... lead to mouth sores, sensitive gums, an irritated throat, and an increased risk of tooth decay. The ...

  6. Gaussian Confinement in a Jkj Decay Model

    NASA Astrophysics Data System (ADS)

    da Silva, Mario L. L.; Hadjimichef, Dimiter; Vasconcellos, Cesar A. Z.

    In microscopic decay models, one attempts to describe hadron strong decays in terms of quark and gluon degrees of freedom. We begin by assuming that strong decays are driven by the same interquark Hamiltonian which determines the spectrum, and that it incorporates gaussian confinement. An A → BC decay matrix element of the JKJ Hamiltonian involves a pair-production current matrix elements times a scatering matrix element. Diagrammatically this corresponds to an interaction between an initial line and produced pair.

  7. Double beta decay: A theoretical overview

    SciTech Connect

    Rosen, S.P.

    1988-01-01

    This paper reviews the theoretical possibility of double beta decay. The titles of the main sections of this paper are: Nuclear physics setting; Particle physics requirements; Kinematical features of the decay modes; Nuclear matrix elements; the Shell model and two-neutrino decay; Quasi-particle random phase approximation; and Future considerations. 18 refs., 7 tabs. (LSP)

  8. Recent results on semileptonic decays at BABAR

    NASA Astrophysics Data System (ADS)

    Serrano, J.; Babar Collaboration

    2009-01-01

    Some recent BABAR results on semileptonic decays are presented. They focus on the determination of the CKM matrix elements |V| and |V| in inclusive and exclusive b→uℓν and b→cℓν decays, and on form factors measurement in exclusive c→sℓν decays.

  9. Decay data evaluation project (DDEP): updated evaluations of the 233Th and 241Am decay characteristics.

    PubMed

    Chechev, Valery P; Kuzmenko, Nikolay K

    2010-01-01

    The results of new decay data evaluations are presented for (233)Th (beta(-)) decay to nuclear levels in (233)Pa and (241)Am (alpha) decay to nuclear levels in (237)Np. These evaluated data have been obtained within the Decay Data Evaluation Project using information published up to 2009.

  10. Decay Data Evaluation Project (DDEP): evaluation of the main 243Cm and 245Cm decay characteristics.

    PubMed

    Chechev, Valery P

    2012-09-01

    The results of new decay data evaluations are presented for (243)Cm (α) decay to nuclear levels in (239)Pu and (245)Cm (α) decay to nuclear levels in (241)Pu. These evaluated data have been obtained within the Decay Data Evaluation Project using information published up to 2011.

  11. Form factors and decay rate of Bc * Dsl+l- decays in the QCD sum rules

    NASA Astrophysics Data System (ADS)

    Zeynali, K.; Bashiry, V.; Zolfagharpour, F.

    2014-08-01

    Rare exclusive decays are analyzed in the framework of the three-point QCD sum rules approach. The two-gluon condensate corrections to the correlation function are included and the form factors of this transition are evaluated. Using the form factors, the decay width and integrated decay rate for these decays are also calculated.

  12. Lyapunov decay in quantum irreversibility.

    PubMed

    García-Mata, Ignacio; Roncaglia, Augusto J; Wisniacki, Diego A

    2016-06-13

    The Loschmidt echo--also known as fidelity--is a very useful tool to study irreversibility in quantum mechanics due to perturbations or imperfections. Many different regimes, as a function of time and strength of the perturbation, have been identified. For chaotic systems, there is a range of perturbation strengths where the decay of the Loschmidt echo is perturbation independent, and given by the classical Lyapunov exponent. But observation of the Lyapunov decay depends strongly on the type of initial state upon which an average is carried out. This dependence can be removed by averaging the fidelity over the Haar measure, and the Lyapunov regime is recovered, as has been shown for quantum maps. In this work, we introduce an analogous quantity for systems with infinite dimensional Hilbert space, in particular the quantum stadium billiard, and we show clearly the universality of the Lyapunov regime. PMID:27140966

  13. Decays of the tau lepton

    SciTech Connect

    Burchat, P.R.

    1986-02-01

    Previous measurements of the branching fractions of the tau lepton result in a discrepancy between the inclusive branching fraction and the sum of the exclusive branching fractions to final states containing one charged particle. The sum of the exclusive branching fractions is significantly smaller than the inclusive branching fraction. In this analysis, the branching fractions for all the major decay modes are measured simultaneously with the sum of the branching fractions constrained to be one. The branching fractions are measured using an unbiased sample of tau decays, with little background, selected from 207 pb/sup -1/ of data accumulated with the Mark II detector at the PEP e/sup +/e/sup -/ storage ring. The sample is selected using the decay products of one member of the ..gamma../sup +/..gamma../sup -/ pair produced in e/sup +/e/sup -/ annihilation to identify the event and then including the opposite member of the pair in the sample. The sample is divided into subgroups according to charged and neutral particle multiplicity, and charged particle identification. The branching fractions are simultaneously measured using an unfold technique and a maximum likelihood fit. The results of this analysis indicate that the discrepancy found in previous experiments is possibly due to two sources. First, the leptonic branching fractions measured in this analysis are about one standard deviation higher than the world average. The measured leptonic branching fractions correspond to a tau lifetime of (3.0 +- 0.2) x 10/sup -13/ s. Secondly, the total branching fraction to one charged hadron plus at least one neutral particle is measured to be (7 +- 3)% higher than the branching fraction expected from a combination of previous measurements and theoretical predictions. It is shown that decay modes involving the eta are not expected to contribute more than 3% to this excess.

  14. Optical spectroscopy and tooth decay

    NASA Astrophysics Data System (ADS)

    Misra, P.; De, T.; Singh, R.

    2005-11-01

    Optical spectroscopy in the ultraviolet, visible and mid-infrared spectral regions has been used to discriminate between healthy and diseased teeth of patients in the age range 15-75 years. Spectral scans of absorbance versus wavenumber and fluorescence intensity versus wavelength have been recorded and investigated for caries and periodontal disease. Such optical diagnostics can prove very useful in the early detection and treatment of tooth decay.

  15. Nuclear structure from radioactive decay

    SciTech Connect

    Wood, J.L.

    1991-09-30

    This report discusses nuclear structure from radioactive decay of the following: Neutron-Deficient Iridium Isotopes; Neutron-Deficient Platinum Isotopes; Neutron-Deficient Gold Isotopes; Neutron-Deficient Mercury Isotopes; Neutron-Deficient Thallium Isotopes; Neutron-Deficient Lead Isotopes; Neutron-Deficient Samarium Isotopes; Neutron-Deficient Promethium Isotopes; Neutron-Deficient Neodymium Isotopes; and Neutron-Deficient Praseodymium Isotopes. Also discussed are Nuclear Systematics and Models.

  16. Nuclear Decay Data: On-going Studies to Address and Improve Radionuclide Decay Characteristics

    NASA Astrophysics Data System (ADS)

    Nichols, Alan L.

    2005-05-01

    Representative decay data studies are described and reviewed, ranging from various measurement programmes to the maintenance of evaluated decay-data libraries. Gross beta-decay measurements are essential to address the decay-data requirements for short-lived fission products, well-defined half-lives are required in assessments of the storage of long-lived radionuclides in waste depositories, and improved decay data continue to be demanded in safeguards, to improve detector-calibration standards, and for medical and analytical applications. Such needs require the measurement of good quality decay data, along with multinational evaluations of decay schemes by means of agreed procedures.

  17. Observation of Doppler broadening in β -delayed proton- γ decay

    DOE PAGES

    Schwartz, S. B.; Wrede, C.; Bennett, M. B.; Liddick, S. N.; Pérez-Loureiro, D.; Bowe, A.; Chen, A. A.; Chipps, K. A.; Cooper, N.; Irvine, D.; et al

    2015-09-14

    Background: The Doppler broadening of gamma-ray peaks is due to nuclear recoil from beta-delayed nucleon emission can be used to measure the energies of the nucleons. This method has never been tested using beta-delayed proton emission or applied to a recoil heavier than A = 10. Purpose: To test and apply this Doppler broadening method using gamma-ray peaks from the P-26(beta p gamma)Al-25 decay sequence. Methods: A fast beam of P-26 was implanted into a planar Ge detector, which was used as a P-26 beta-decay trigger. The SeGA array of high-purity Ge detectors was used to detect gamma rays frommore » the P-26(beta p gamma)Al-25 decay sequence. Results: Radiative Doppler broadening in beta-delayed proton-gamma decay was observed for the first time. Moreover, the Doppler broadening analysis method was verified using the 1613-keV gamma-ray line for which the proton energies were previously known. The 1776-keV gamma ray de-exciting the 2720 keV Al-25 level was observed in P-26(beta p gamma)Al-25 decay for the first time and used to determine that the center-of-mass energy of the proton emission feeding the 2720-keV level is 5.1 +/- 1.0 (stat.) +/- 0.6 (syst.) MeV, corresponding to a Si-26 excitation energy of 13.3 +/- 1.0 (stat.) +/- 0.6 (syst.) MeV for the proton-emitting level. Conclusions: Finally, the Doppler broadening method has been demonstrated to provide practical measurements of the energies for beta-delayed nucleon emissions populating excited states of nuclear recoils at least as heavy as A = 25.« less

  18. Radiation Therapy

    MedlinePlus

    Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from ... half of all cancer patients receive it. The radiation may be external, from special machines, or internal, ...

  19. Radiation Therapy

    MedlinePlus

    ... people who have radiation therapy may feel more tired than usual, not feel hungry, or lose their ... of radiation therapy include: Fatigue. Fatigue, or feeling tired, is the most common side effect of radiation ...

  20. Radiation therapy

    MedlinePlus

    ... Because radiation is most harmful to quickly growing cells, radiation therapy damages cancer cells more than normal cells. ... cells from growing and dividing, and leads to cell death. Radiation therapy is used to fight many types of ...

  1. Lattice study of semileptonic B decays: B¯-->Dlν¯ decays

    NASA Astrophysics Data System (ADS)

    Bowler, K. C.; Hazel, N. M.; Henty, D. S.; Hoeber, H.; Kenway, R. D.; Richards, D. G.; Shanahan, H. P.; Simone, J. N.; Lellouch, L.; Nieves, J.; Sachrajda, C. T.; Wittig, H.

    1995-11-01

    We present a study of semileptonic B¯-->Dlν¯ decays in quenched lattice QCD through a calculation of the matrix element on a 243×48 lattice at β=6.2, using an O(a)-improved fermion action. We perform the calculation for several values of the initial and final heavy-quark masses around the charm mass, and three values of the light-(anti)quark mass around the strange mass. Because the charm quark has a bare mass which is almost 1/3 the inverse lattice spacing, we study the ensuing mass-dependent discretization errors, and propose a procedure for subtracting at least some of them nonperturbatively. We extract the form factors h+ and h-. After radiative corrections, we find that h+ displays no dependence on the heavy-quark mass, enabling us to identify it with an Isgur-Wise function ξ. Interpolating the light-quark mass to that of the strange, we obtain an Isgur-Wise function relevant for B¯s-->D(*)slν¯ decays which has a slope -ξ's=1.2+2-2 (stat)+2-1 (syst) at zero recoil. An extrapolation to a massless light quark enables us to obtain an Isgur-Wise function relevant for B¯-->D(*)lν¯ decays. This function has a slope -ξu,d'=0.9+2-3 (stat)+4-2 (syst) at zero recoil. We observe a slight decrease in the magnitude of the central value of the slope as the mass of the light quark is reduced; given the errors, however, the significance of this observation is limited. We then use these functions, in conjunction with heavy-quark effective theory, to extract Vcb with no free parameters from the B¯-->D*lν¯ decay rate measured by the ALEPH, ARGUS, and CLEO Collaborations. Using the CLEO data, for instance, we obtain ||Vcb|| =0.037+1+2+4-1-2-1[0.99/1+βA1(1)]1/1 +δ21/mc, where δ21/mc is the power correction inversely proportional to the square of the charm quark mass, and βA1(1) is the relevant radiative correction at zero recoil. Here, the first set of errors is experimental, the second represents the statistical error, and the third

  2. Quark Mixing, CP Violation and Rare Decays After the Top Quark Discovery

    NASA Astrophysics Data System (ADS)

    Buras, Andrzej J.; Fleischer, Robert

    We review the highlights of quark mixing, particle-antiparticle mixing, CP violation and rare K- and B-decays in the Standard Model. The top quark discovery, the precise measurement of its mass, the improved knowledge of the couplings Vcb and Vub, and the calculations of NLO short distance QCD corrections improved considerably the predictions for various decay rates, the determination of the couplings Vtd and Vts and of the complex phase in the Cabibbo-Kobayashi-Maskawa matrix. After presenting the general theoretical framework for weak decays, we discuss the following topics in detail: i) the CKM matrix, its most convenient parametrizations and the unitarity triangle, ii) the CP-violating parameter ɛK and B^{0}_{d,s} - bar{B}^{0}_{d,s} mixings, iii) the ratio ɛ'/ɛ, iv) the rare K-decays KL → π0e+e-, K^{+} → π^{+}νoverline{ν}, K_L → π^{0}νoverline{ν} and KL → μ+μ-, v) the radiative decays B → Xsγ and B → Xsl+l-, vi) the rare B-decays B → X_{s,d}νoverline{ν} and Bd,s → l+l-, vii) CP violation in neutral and charged B-decays putting emphasis on clean determinations of the angles of the unitarity triangle, and viii) the role of electroweak penguins in B-decays. We present several future visions demonstrating very clearly the great potential of CP asymmetries in B-decays and of clean K-decays such as K^{+} → π^{+}νoverline{ν} and K_L → π^{0}νoverline{ν} in the determination of the CKM parameters and in decisive testing of the Standard Model. An outlook for the coming years ends our review.

  3. Radiative and Electroweak Penguins at Belle

    SciTech Connect

    Hyun, Hyo Jung

    2010-02-10

    Radiative and electroweak penguin decays of B mesons are a sensitive probe of new physics beyond the Standard Model. We study the inclusive and exclusive radiative and electroweak penguin decays of B meson and also search an exotic particle seen by the HyperCP experiment. The measurements are based on a large data sample of 605 fb{sup -1} containing 657 millions BB-bar pairs collected at the UPSILON(4S) with the Belle detector at the KEKB energy asymmetric e{sup +}e{sup -} collider.

  4. Atmospheric radiation

    SciTech Connect

    Harshvardhan, M.R. )

    1991-01-01

    Studies of atmospheric radiative processes are summarized for the period 1987-1990. Topics discussed include radiation modeling; clouds and radiation; radiative effects in dynamics and climate; radiation budget and aerosol effects; and gaseous absorption, particulate scattering and surface reflection. It is concluded that the key developments of the period are a defining of the radiative forcing to the climate system by trace gases and clouds, the recognition that cloud microphysics and morphology need to be incorporated not only into radiation models but also climate models, and the isolation of a few important unsolved theoretical problems in atmospheric radiation.

  5. Model-independent search for the decay B+→l+νlγ

    NASA Astrophysics Data System (ADS)

    Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Tico, J. Garra; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lynch, G.; Osipenkov, I. L.; Tackmann, K.; Tanabe, T.; Hawkes, C. M.; Soni, N.; Watson, A. T.; Koch, H.; Schroeder, T.; Asgeirsson, D. J.; Fulsom, B. G.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Barrett, M.; Khan, A.; Randle-Conde, A.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Atmacan, H.; Gary, J. W.; Liu, F.; Long, O.; Vitug, G. M.; Yasin, Z.; Sharma, V.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Mazur, M. A.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Schalk, T.; Schumm, B. A.; Seiden, A.; Wang, L.; Winstrom, L. O.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Fang, F.; Hitlin, D. G.; Narsky, I.; Ongmongkolkul, P.; Piatenko, T.; Porter, F. C.; Andreassen, R.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Hirschauer, J. F.; Nagel, M.; Nauenberg, U.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Toki, W. H.; Wilson, R. J.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, T. M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Kobel, M. J.; Nogowski, R.; Schubert, K. R.; Schwierz, R.; Volk, A.; Bernard, D.; Latour, E.; Verderi, M.; Clark, P. J.; Playfer, S.; Watson, J. E.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Fioravanti, E.; Franchini, P.; Luppi, E.; Munerato, M.; Negrini, M.; Petrella, A.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Contri, R.; Guido, E.; Lo Vetere, M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Tosi, S.; Chaisanguanthum, K. S.; Morii, M.; Adametz, A.; Marks, J.; Schenk, S.; Uwer, U.; Bernlochner, F. U.; Klose, V.; Lacker, H. M.; Bard, D. J.; Dauncey, P. D.; Tibbetts, M.; Behera, P. K.; Charles, M. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Dong, L.; Eyges, V.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Arnaud, N.; Béquilleux, J.; D'Orazio, A.; Davier, M.; Derkach, D.; da Costa, J. Firmino; Grosdidier, G.; Le Diberder, F.; Lepeltier, V.; Lutz, A. M.; Malaescu, B.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Clarke, C. K.; di Lodovico, F.; Sacco, R.; Sigamani, M.; Cowan, G.; Paramesvaran, S.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Hafner, A.; Alwyn, K. E.; Bailey, D.; Barlow, R. J.; Jackson, G.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Dallapiccola, C.; Salvati, E.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Henderson, S. W.; Sciolla, G.; Spitznagel, M.; Yamamoto, R. K.; Zhao, M.; Lindemann, D. M.; Patel, P. M.; Robertson, S. H.; Schram, M.; Biassoni, P.; Lazzaro, A.; Lombardo, V.; Palombo, F.; Stracka, S.; Bauer, J. M.; Cremaldi, L.; Godang, R.; Kroeger, R.; Sonnek, P.; Summers, D. J.; Zhao, H. W.; Simard, M.; Taras, P.; Nicholson, H.; de Nardo, G.; Lista, L.; Monorchio, D.; Onorato, G.; Sciacca, C.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Corwin, L. A.; Honscheid, K.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Regensburger, J. J.; Sekula, S. J.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Kolb, J. A.; Lu, M.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Castelli, G.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Voci, C.; Del Amo Sanchez, P.; Ben-Haim, E.; Bonneaud, G. R.; Briand, H.; Chauveau, J.; Hamon, O.; Leruste, Ph.; Marchiori, G.; Ocariz, J.; Perez, A.; Prendki, J.; Sitt, S.; Gladney, L.; Biasini, M.; Manoni, E.; Angelini, C.; Batignani, G.; Bettarini, S.; Calderini, G.; Carpinelli, M.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Morganti, M.; Neri, N.; Paoloni, E.; Rizzo, G.; Walsh, J. J.; Pegna, D. Lopes; Lu, C.; Olsen, J.; Smith, A. J. S.; Telnov, A. V.; Anulli, F.; Baracchini, E.; Cavoto, G.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Jackson, P. D.; Gioi, L. Li; Mazzoni, M. A.; Morganti, S.; Piredda, G.; Renga, F.; Voena, C.; Ebert, M.; Hartmann, T.; Schröder, H.; Waldi, R.; Adye, T.; Franek, B.; Olaiya, E. O.; Wilson, F. F.; Emery, S.; Esteve, L.; de Monchenault, G. Hamel; Kozanecki, W.; Vasseur, G.; Yèche, Ch.; Zito, M.; Allen, M. T.; Aston, D.; Bartoldus, R.; Benitez, J. F.; Cenci, R.; Coleman, J. P.; Convery, M. R.; Dingfelder, J. C.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Field, R. C.; Sevilla, M. Franco; Gabareen, A. M.; Graham, M. T.; Grenier, P.; Hast, C.; Innes, W. R.; Kaminski, J.; Kelsey, M. H.; Kim, H.; Kim, P.; Kocian, M. L.; Leith, D. W. G. S.; Li, S.; Lindquist, B.; Luitz, S.; Luth, V.; Lynch, H. L.; Macfarlane, D. B.; Marsiske, H.; Messner, R.; Muller, D. R.; Neal, H.; Nelson, S.; O'Grady, C. P.; Ofte, I.; Perl, M.; Ratcliff, B. N.; Roodman, A.; Salnikov, A. A.; Schindler, R. H.; Schwiening, J.; Snyder, A.; Su, D.; Sullivan, M. K.; Suzuki, K.; Swain, S. K.; Thompson, J. M.; Va'Vra, J.; Wagner, A. P.; Weaver, M.; West, C. A.; Wisniewski, W. J.; Wittgen, M.; Wright, D. H.; Wulsin, H. W.; Yarritu, A. K.; Young, C. C.; Ziegler, V.; Chen, X. R.; Liu, H.; Park, W.; Purohit, M. V.; White, R. M.; Wilson, J. R.; Burchat, P. R.; Edwards, A. J.; Miyashita, T. S.; Ahmed, S.; Alam, M. S.; Ernst, J. A.; Pan, B.; Saeed, M. A.; Zain, S. B.; Soffer, A.; Spanier, S. M.; Wogsland, B. J.; Eckmann, R.; Ritchie, J. L.; Ruland, A. M.; Schilling, C. J.; Schwitters, R. F.; Wray, B. C.; Drummond, B. W.; Izen, J. M.; Lou, X. C.; Bianchi, F.; Gamba, D.; Pelliccioni, M.; Bomben, M.; Bosisio, L.; Cartaro, C.; Della Ricca, G.; Lanceri, L.; Vitale, L.; Azzolini, V.; Lopez-March, N.; Martinez-Vidal, F.; Milanes, D. A.; Oyanguren, A.; Albert, J.; Banerjee, Sw.; Bhuyan, B.; Choi, H. H. F.; Hamano, K.; King, G. J.; Kowalewski, R.; Lewczuk, M. J.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Gershon, T. J.; Harrison, P. F.; Ilic, J.; Latham, T. E.; Mohanty, G. B.; Puccio, E. M. T.; Band, H. R.; Chen, X.; Dasu, S.; Flood, K. T.; Pan, Y.; Prepost, R.; Vuosalo, C. O.; Wu, S. L.

    2009-12-01

    We present a search for the radiative leptonic decay B+→ℓ+νℓγ, where ℓ=e, μ, using a data sample of 465×106 BB¯ pairs collected by the BABAR experiment. In this analysis, we fully reconstruct the hadronic decay of one of the B mesons in Υ(4S)→B+B- decays, then search for evidence of B+→ℓ+νℓγ in the rest of the event. We observe no significant evidence of signal decays and report model-independent branching fraction upper limits of B(B+→e+νeγ)<17×10-6, B(B+→μ+νμγ)<24×10-6, and B(B+→ℓ+νℓγ)<15.6×10-6 (ℓ=e or μ), all at the 90% confidence level.

  6. b--> sl{sup +}l{sup {minus}} Decays in and Beyond the Standard Model

    SciTech Connect

    Hiller, Gudrun

    2000-08-11

    The authors briefly review the status of rare radiative and semileptonic b --> s(gamma,l{sup +}l{sup {minus}}), (l=e,mu) decays. They discuss possible signatures of new physics in these modes and emphasize the role of the exclusive channels. In particular, measurements of the Forward-Backward asymmetry in B -->K*l{sup +}l{sup {minus}} decays and its zero provide a clean test of the Standard Model, complementary to studies in b -->s gamma decays. Further, the Forward-Backward CP asymmetry in B --> K*l{sup +}l{sup {minus}} decays is sensitive to possible non-standard sources of CP violation mediated by Flavor changing neutral current Z-penguins.

  7. {beta} decay of 129Cd and excited states in 129In

    SciTech Connect

    Taprogge, J.; Jungclaus, A.; Grawe, H.; Nishimura, S.; Doornenbal, P.; Lorusso, G.; Simpson, G. S.; Soderstrom, P. A.; Sumikama, T.; Xu, Z. Y.; Kondev, F. G.

    2015-05-26

    The β decay of Cd 129 , produced in the relativistic fission of a U 238 beam, was experimentally studied at the RIBF facility at the RIKEN Nishina Center. From the γ radiation emitted after the β decays, a level scheme of In 129 was established comprising 31 excited states and 69 γ -ray transitions. The experimentally determined level energies are compared to state-of-the-art shell-model calculations. The half-lives of the two β -decaying states in Cd 129 were deduced and the β feeding to excited states in In 129 were analyzed. It is found that, as in most cases in the Z<50 , N≤82 region, both decays are dominated by the ν0g 7/2 →π0g 9/2 Gamow–Teller transition, although the contribution of first-forbidden transitions cannot be neglected.

  8. Beta Decay in the Field of an Electromagnetic Wave and Experiments on Measuring the Neutrino Mass

    SciTech Connect

    Dorofeev, O.F.; Lobanov, A.E.

    2005-06-01

    Investigations of the effect of an electromagnetic wave field on the beta-decay process are used to analyze the tritium-decay experimental data on the neutrino mass. It is shown that the electromagnetic wave can distort the beta spectrum, shifting the end point to the higher energy region. This phenomenon is purely classical and it is associated with the electron acceleration in the radiation field. Since strong magnetic fields exist in setups for precise measurement of the neutrino mass, the indicated field can appear owing to the synchrotron radiation mechanism. The phenomenon under consideration can explain the experimentally observed anomalies in the spectrum of the decay electrons; in particular, the effect of the 'negative square of the neutrino mass'.

  9. Search for monenergetic gamma rays from psi /3684/ decay

    NASA Technical Reports Server (NTRS)

    Simpson, J. W.; Beron, B. L.; Ford, R. L.; Hofstadter, R.; Howell, R. L.; Hughes, E. B.; Liberman, A. D.; Martin, T. W.; Oneill, L. H.; Hilger, E.

    1975-01-01

    Results are reported of a search for monoenergetic gamma rays with energies above 50 MeV arising from psi (3684) decay. The measurements were made by operating an electron-positron storage ring at a center-of-mass energy of 3684 MeV and detecting the secondary gamma rays with large-crystal NaI(T1) spectrometers. No significant evidence is found for the emission of such radiation, and upper limits are placed on such emissions for energies above 50 MeV.

  10. Searching for decaying axionlike dark matter from clusters of galaxies.

    PubMed

    Riemer-Sørensen, Signe; Zioutas, Konstantin; Hansen, Steen H; Pedersen, Kristian; Dahle, Håkon; Liolios, Anastasios

    2007-09-28

    We constrain the lifetime of radiatively decaying dark matter in clusters of galaxies inspired by generic Kaluza-Klein axions, which have been invoked as a possible explanation for the solar coronal x-ray emission. These particles can be produced inside stars and remain confined by the gravitational potential of clusters. By analyzing x-ray observations of merging clusters, where gravitational lensing observations have identified massive, baryon poor structures, we derive the first cosmological lifetime constraint on this kind of particles of tau > or = 10(23) sec.

  11. Searching for Decaying Axionlike Dark Matter from Clusters of Galaxies

    SciTech Connect

    Riemer-Soerensen, Signe; Hansen, Steen H.; Pedersen, Kristian; Zioutas, Konstantin; Dahle, Haakon; Liolios, Anastasios

    2007-09-28

    We constrain the lifetime of radiatively decaying dark matter in clusters of galaxies inspired by generic Kaluza-Klein axions, which have been invoked as a possible explanation for the solar coronal x-ray emission. These particles can be produced inside stars and remain confined by the gravitational potential of clusters. By analyzing x-ray observations of merging clusters, where gravitational lensing observations have identified massive, baryon poor structures, we derive the first cosmological lifetime constraint on this kind of particles of {tau} > or approx. 10{sup 23} sec.

  12. The use of decay rates to analyse the performance of railway track in rolling noise generation

    NASA Astrophysics Data System (ADS)

    Jones, C. J. C.; Thompson, D. J.; Diehl, R. J.

    2006-06-01

    Through the development and testing of theoretical models for rolling noise in the past, it has been well demonstrated that the rate of decay of vibration along the rail is closely linked to the noise performance of the track, since it controls the effective radiating length of the rail. The decay rates of vibration along the rail have long been used by researchers as an intermediate, measurable parameter by which to test and improve the accuracy of prediction models. Recently, it has been suggested that the decay rates should be used as a criterion for the selection of track for noise measurements that are part of the acceptance testing of interoperable trains in Europe. In this context, a more detailed understanding of the factors that affect the measurement of decay rates and a consistent approach to the data processing have become important topics. Here, a method is suggested for the calculation of decay rates from frequency response measurements. Different effects are shown in the measured decay rates of a ballasted track with mono-bloc sleepers, a slab track and a ballasted track with bi-bloc sleepers. In the last case, a model for a periodically supported track is used to study the effects observed. It is shown that a peak in the decay rate just above the pinned-pinned frequency may be overestimated because of the measurement procedure that has been used.

  13. Mechanisms of fluorescence decays of colloidal CdSe-CdS/ZnS quantum dots unraveled by time-resolved fluorescence measurement.

    PubMed

    Xu, Hao; Chmyrov, Volodymyr; Widengren, Jerker; Brismar, Hjalmar; Fu, Ying

    2015-11-01

    By narrowing the detection bandpass and increasing the signal-to-noise ratio in measuring the time-resolved fluorescence decay spectrum of colloidal CdSe-CdS/ZnS quantum dots (QDs), we show that directly after the photoexcitation, the fluorescence decay spectrum is characterized by a single exponential decay, which represents the energy relaxation of the photogenerated exciton from its initial high-energy state to the ground exciton state. The fluorescence decay spectrum of long decay time is in the form of β/t(2), where β is the radiative recombination time of the ground-state exciton and t is the decay time. Our findings provide us with a direct and quantitative link between fluorescence decay measurement data and fundamental photophysics of QD exciton, thereby leading to a novel way of applying colloidal QDs to study microscopic, physical and chemical processes in many fields including biomedicine. PMID:26426293

  14. Mechanisms of fluorescence decays of colloidal CdSe-CdS/ZnS quantum dots unraveled by time-resolved fluorescence measurement.

    PubMed

    Xu, Hao; Chmyrov, Volodymyr; Widengren, Jerker; Brismar, Hjalmar; Fu, Ying

    2015-11-01

    By narrowing the detection bandpass and increasing the signal-to-noise ratio in measuring the time-resolved fluorescence decay spectrum of colloidal CdSe-CdS/ZnS quantum dots (QDs), we show that directly after the photoexcitation, the fluorescence decay spectrum is characterized by a single exponential decay, which represents the energy relaxation of the photogenerated exciton from its initial high-energy state to the ground exciton state. The fluorescence decay spectrum of long decay time is in the form of β/t(2), where β is the radiative recombination time of the ground-state exciton and t is the decay time. Our findings provide us with a direct and quantitative link between fluorescence decay measurement data and fundamental photophysics of QD exciton, thereby leading to a novel way of applying colloidal QDs to study microscopic, physical and chemical processes in many fields including biomedicine.

  15. Pelvic radiation - discharge

    MedlinePlus

    Radiation of the pelvis - discharge; Cancer treatment - pelvic radiation; Prostate cancer - pelvic radiation; Ovarian cancer - pelvic radiation; Cervical cancer - pelvic radiation; Uterine cancer - pelvic radiation; Rectal cancer - ...

  16. HALF-LIVES OF LONG-LIVED A-DECAY, B-DECAY, BB-DECAY AND SPONTANEOUS FISSION NUCLIDES.

    SciTech Connect

    HOLDEN,N.E.

    2001-06-29

    In his review of radionuclides for dating purposes, Roth noted that there were a large number of nuclides, normally considered ''stable'' but which are radioactive with a very long half-life. Roth suggested that I review the data on the half-life values of these long-lived nuclides for a discussion session at the next meeting. These half-life values for long-lived nuclides include those due to various decay modes, {alpha}-decay, {beta}-decay, electron capture decay, {beta}{beta}-decay and spontaneous fission decay. This report is preliminary but will provide a quick overview of the extensive table of data on the recommendations from that review.

  17. Exploring the simplest purely baryonic decay processes

    NASA Astrophysics Data System (ADS)

    Geng, C. Q.; Hsiao, Y. K.; Rodrigues, Eduardo

    2016-07-01

    Though not considered in general, purely baryonic decays could shed light on the puzzle of the baryon number asymmetry in the universe by means of a better understanding of the baryonic nature of our matter world. As such, they constitute a yet unexplored class of decay processes worth investigating. We propose to search for purely baryonic decay processes at the LHCb experiment. No such type of decay has ever been observed. In particular, we concentrate on the decay Λb0→p p ¯n , which is the simplest purely baryonic decay mode, with solely spin-1 /2 baryons involved. We predict its decay branching ratio to be B (Λb0→p p ¯ n )=(2. 0-0.2+0.3)×10-6 , which is sufficiently large to make the decay mode accessible to LHCb. Our study can be extended to other purely baryonic decays such as Λb0→p p ¯ Λ , Λb0→Λ p ¯ Λ , and Λb0→Λ Λ ¯Λ , as well as to similar decays of antitriplet b baryons such as Ξb0 ,-.

  18. Gravitational effects on inflaton decay

    SciTech Connect

    Ema, Yohei; Jinno, Ryusuke; Mukaida, Kyohei; Nakayama, Kazunori

    2015-05-22

    We point out that the inflaton inevitably couples to all non-conformally coupled matters gravitationally through an oscillation in the Hubble parameter or the cosmic scale factor. It leads to particle production during the inflaton oscillation regime, which is most efficient just after inflation. Moreover, the analysis is extended to the model with non-minimal inflaton couplings to gravity, in which the Hubble parameter oscillates more violently. We apply our results to the graviton production by the inflaton: gravitons are also produced just after inflation, but the non-minimal coupling does not induce inflaton decay into the graviton pair.

  19. Vacuum Decay via Lorentzian Wormholes

    NASA Astrophysics Data System (ADS)

    Rosales, J. L.

    We speculate about the space-time description due to the presence of Lorentzian worm-holes (handles in space-time joining two distant regions or other universes) in quantum gravity. The semiclassical rate of production of these Lorentzian wormholes in Reissner-Nordström space-times is calculated as a result of the spontaneous decay of vacuum due to a real tunneling configuration. In the magnetic case it only depends on the value of the field theoretical fine structure constant. We predict that the quantum probability corresponding to the nucleation of such geodesically complete space-times should be acutally negligible in our physical Universe.

  20. Proton decay studies at HRIBF

    SciTech Connect

    Batchelder, J.C.; Bingham, C.R.; Rykaczewski, K.; Toth, K.S.; Mas, J.F.; McConnell, J.W.; Yu, C.; Bingham, C.R.; Grzywacz, R.; Kim, S.H.; Weintraub, W.; Rykaczewski, K.; Janas, Z.; Karny, M.; Davinson, T.; Slinger, R.C.; Woods, P.J.; Ginter, T.N.; Gross, C.J.; MacDonald, B.D.; Piechaczek, A.; Zganjar, E.F.; Ressler, J.J.; Walters, W.B.; Szerypo, J.

    1998-12-01

    A double-sided Si-strip detector system has been installed and commissioned at the focal plane of the Recoil Mass Spectrometer at the Holifield Radioactive Ion Beam Facility. The system can be used for heavy charged particle emission studies with half-lives as low as a few {mu}sec. In this paper we present identification and study of the decay properties of the five new proton emitters: {sup 140}Ho, {sup 141m}Ho, {sup 145}Tm, {sup 150m}Lu and {sup 151m}Lu. {copyright} {ital 1998 American Institute of Physics.}

  1. Classical picture of postexponential decay

    SciTech Connect

    Torrontegui, E.; Muga, J. G.; Martorell, J.; Sprung, D. W. L.

    2010-04-15

    Postexponential decay of the probability density of a quantum particle leaving a trap can be reproduced accurately, except for interference oscillations at the transition to the postexponential regime, by means of an ensemble of classical particles emitted with constant probability per unit time and the same half-life as the quantum system. The energy distribution of the ensemble is chosen to be identical to the quantum distribution, and the classical point source is located at the scattering length of the corresponding quantum system. A one-dimensional example is provided to illustrate the general argument.

  2. Stellar structures and the enigma of pulsars rotation frequency decay

    NASA Astrophysics Data System (ADS)

    de Oliveira, H. O.; Marinho, R. M., Jr.; Maglhaes, N. S.

    2015-07-01

    Pulsars are astrophysical objects normally modelled as compact neutron stars that originated from the collapse of another star. This model, that we name canonical, assumes that pulsars are described by spherical magnetized dipoles that rotate, usually with the magnetic axis misaligned to the rotation axis. This misalignment would be responsible for the observation of radiation emitted in well-defined time intervals in a certain direction (lighthouse effect), the typical observational characteristic of this kind of star. It has been noticed that the rotation frequency of pulsars is slowly decaying with time (spin down), implying a gradual decrease of the rotational angular velocity (Ω). Such decay can be quantified by a dimensionless parameter called “braking index” (“n”), given by n = ΩΩ/(Ω)2, where a dot indicates a time derivative. The canonical model predicts that this index has one only value for all pulsars, equal to three. However, observational data indicate that actual braking indices are less than three, representing an enigma. The main goal of this research is the exploration of a more precise model for pulsars’ rotation frequency decay.

  3. Baryogenesis from decaying magnetic helicity

    NASA Astrophysics Data System (ADS)

    Kamada, Kohei; Long, Andrew J.

    2016-09-01

    As a result of the Standard Model chiral anomalies, baryon number is violated in the early Universe in the presence of a hypermagnetic field with varying helicity. We investigate whether the matter/antimatter asymmetry of the Universe can be created from the decaying helicity of a primordial (hyper)magnetic field before and after the electroweak phase transition. In this model, baryogenesis occurs without (B -L )-violation, since the (B +L ) asymmetry generated by the hypermagnetic field counteracts the washout by electroweak sphalerons. At the electroweak crossover, the hypermagnetic field becomes an electromagnetic field, which does not source (B +L ). Although the sphalerons remain in equilibrium for a time, washout is avoided since the decaying magnetic helicity sources chirality. The relic baryon asymmetry is fixed when the electroweak sphaleron freezes out. Under reasonable assumptions, a baryon asymmetry of nB/s ≃4 ×10-12 can be generated from a maximally helical, right-handed (hyper)magnetic field that has a field strength of B0≃10-14 Gauss and coherence length of λ0≃1 pc today. Relaxing an assumption that relates λ0 to B0, the model predicts nB/s ≳10-10, which could potentially explain the observed baryon asymmetry of the Universe.

  4. Bs decays at the Tevatron

    SciTech Connect

    Giurgiu, Gavril; /Johns Hopkins U.

    2010-09-01

    The authors present measurements of the branching ratio and of the polarization amplitudes in charmless B{sub s} {yields} {phi}{phi} decays using data corresponding to 2.9 fb{sup -1} of integrated luminosity, collected by the CDF experiment at the Tevatron. The branching ratio in B{sub s} {yields} {phi}{phi} decays is measured relative to the normalization mode B{sub s} {yields} J/{Psi}{phi} be {Beta}(B{sub s} {yields} {phi}{phi})/{Beta}(B{sub s} {yields} J/{Psi}{phi}) = [1.78 {+-} 0.14(stat) {+-} 0.20(syst)] x 10{sup -2}. Using the experimental value of {Beta}(B{sub s} {yields} J/{Psi}{phi}) they determine the B{sub s} {yields} {phi}{phi} branching ratio {Beta}(B{sub s} {yields} {phi}{phi}) = 2.40 {+-} 0.21(stat) {+-} 0.27(syst) {+-} 0.82(BR) x 10{sup -5}. The polarization fractions are measured for the first time in this analysis and found to be: |A{sub 0}|{sup 2} = 0.348 {+-} 0.041(stat) {+-} 0.021(syst); |A{sub {parallel}}|{sup 2} = 0.287 {+-} 0.043(stat) {+-} 0.011(syst); and |A{sub {perpendicular}}|{sup 2} = 0.365 {+-} 0.044(stat) {+-} 0.027(syst).

  5. Dark Decay of the Top Quark

    SciTech Connect

    Kong, Kyoungchul; Lee, Hye-Sung; Park, Myeonghun

    2014-04-01

    We suggest top quark decays as a venue to search for light dark force carriers. The top quark is the heaviest particle in the standard model whose decays are relatively poorly measured, allowing sufficient room for exotic decay modes from new physics. A very light (GeV scale) dark gauge boson (Z') is a recently highlighted hypothetical particle that can address some astrophysical anomalies as well as the 3.6sigma deviation in the muon g-2 measurement. We present and study a possible scenario that top quark decays as t-->bW+Z's. This is the same as the dominant top quark decay (t-->bW) accompanied by one or multiple dark force carriers. The Z' can be easily boosted, and it can decay into highly collimated leptons (lepton-jet) with large branching ratio. We discuss the implications for the Large Hadron Collider experiments including the analysis based on the lepton-jets.

  6. Rare decays at the LHCb experiment

    NASA Astrophysics Data System (ADS)

    Lanfranchi, G.

    2015-01-01

    Rare flavour-changing neutral-current (FCNC) decays of beauty and charm quarks, lepton flavour- and lepton-number-violating decays can provide a powerful probe for as yet unobserved virtual particles. Recent results on these topics from the LHCb experiment are reviewed. Particular attention is paid to the angular distribution of the B^0 → K^{*0}μ^+μ^- decay, where a measurement performed by LHCb shows a local discrepancy of 3.7 standard deviations with respect to the SM prediction. Using the decay B+ → K+ π+π- γ , LHCb have also been able to demonstrate the polarisation of photons produced in b → s transitions. An update for the studies dedicated to decays τ+ → μ+ μ- μ+ and B^0_{(s)} → μ^{±} e^{∓} and to the on-shell Majorana neutrinos coupling to muons in the B+ → π- μ+ μ+ decay channel are also presented.

  7. Dark decay of the top quark

    SciTech Connect

    Kong, Kyoungchul; Lee, Hye -Sung; Park, Myeonghun

    2014-04-01

    We suggest top quark decays as a venue to search for light dark force carriers. Top quark is the heaviest particle in the standard model whose decays are relatively poorly measured, allowing sufficient room for exotic decay modes from new physics. A very light (GeV scale) dark gauge boson (Z') is a recently highlighted hypothetical particle that can address some astrophysical anomalies as well as the 3.6 σ deviation in the muon g-2 measurement. We present and study a possible scenario that top quark decays as t → b W + Z's. This is the same as the dominant top quark decay (t → b W) accompanied by one or multiple dark force carriers. The Z' can be easily boosted, and it can decay into highly collimated leptons (lepton-jet) with large branching ratio. In addition, we discuss the implications for the Large Hadron Collider experiments including the analysis based on the lepton-jets.

  8. Radiations from hot nuclei

    NASA Technical Reports Server (NTRS)

    Malik, F. Bary

    1993-01-01

    The investigation indicates that nuclei with excitation energy of a few hundred MeV to BeV are more likely to radiate hot nuclear clusters than neutrons. These daughter clusters could, furthermore, de-excite emitting other hot nuclei, and the chain continues until these nuclei cool off sufficiently to evaporate primarily neutrons. A few GeV excited nuclei could radiate elementary particles preferentially over neutrons. Impact of space radiation with materials (for example, spacecraft) produces highly excited nuclei which cool down emitting electromagnetic and particle radiations. At a few MeV excitation energy, neutron emission becomes more dominant than gamma-ray emission and one often attributes the cooling to take place by successive neutron decay. However, a recent experiment studying the cooling process of 396 MeV excited Hg-190 casts some doubt on this thinking, and the purpose of this investigation is to explore the possibility of other types of nuclear emission which might out-compete with neutron evaporation.

  9. Dark radiation emerging after big bang nucleosynthesis?

    SciTech Connect

    Fischler, Willy; Meyers, Joel

    2011-03-15

    We show how recent data from observations of the cosmic microwave background may suggest the presence of additional radiation density which appeared after big bang nucleosynthesis. We propose a general scheme by which this radiation could be produced from the decay of nonrelativistic matter, we place constraints on the properties of such matter, and we give specific examples of scenarios in which this general scheme may be realized.

  10. The distribution of sunspot decay rates

    NASA Astrophysics Data System (ADS)

    Martinez Pillet, V.; Moreno-Insertis, F.; Vazquez, M.

    1993-07-01

    The distribution of sunspot decay rates is studied using the Greenwich Photoheliographic Results (GPR) for a total of approximately hundred years between 1874 and 1976. The decay rates are seen to be lognormally distributed. The discrepancies between the decay rates given in the past by different authors are shown to originate as a consequence of this asymmetric distribution. It is pointed out that the extended tails shown by the lognormal distributions are associated to spots decaying much faster than suggested by Bumba's (1963) work. A cycle by cycle analysis of the lognormal distributions associated with each sunspot group type and for single spots is presented. The differences between the nine solar cycles involved are studied. As a remarkable property of the decay process, we show that it happens at a nearly constant total to umbral area ratio. This property holds for decaying spots which are still large enough to show a penumbra. We have studied the suitability of a decay law with the instantaneous decay rate proportional to the length of the spot boundary. This law predicts a parabolic decay pattern with some specific characteristics. No definite conclusion in favour of this law is reached, but it is suggested that a linear decay is as weakly supported by the GPR data as a peripheral one. On the other hand, weak non-linearities are seen in the decay of isolated spots with a clear tendency to produce a convex pattern in the area vs. time diagram. The implication is that sunspot decay is braked as time proceeds.

  11. Spectroscopy of element 115 decay chains

    SciTech Connect

    Rudolph, Dirk; Forsberg, U.; Golubev, P.; Sarmiento, L. G.; Yakushev, A.; Andersson, L.-L.; Di Nitto, A.; Duehllmann, Ch. E.; Gates, J. M.; Gregorich, K. E.; Gross, Carl J; Hessberger, F. P.; Herzberg, R.-D; Khuyagbaatar, J.; Kratz, J. V.; Rykaczewski, Krzysztof Piotr; Schaedel, M.; Aberg, S.; Ackermann, D.; Block, M.; Brand, H.; Carlsson, B. G.; Cox, D.; Derkx, X.; Eberhardt, K.; Even, J.; Fahlander, C.; Gerl, J.; Jaeger, E.; Kindler, B.; Krier, J.; Kojouharov, I.; Kurz, N.; Lommel, B.; Mistry, A.; Mokry, C.; Nitsche, H.; Omtvedt, J. P.; Papadakis, P.; Ragnarsson, I.; Runke, J.; Schaffner, H.; Schausten, B.; Thoerle-Pospiech, P.; Torres, T.; Traut, T.; Trautmann, N.; Tuerler, A.; Ward, A.; Ward, D. E.; Wiehl, N.

    2013-01-01

    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.

  12. 7 CFR 51.898 - Decay.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States.... Slight surface development of green mold (Cladosporium) shall not be considered decay....

  13. Unique forbidden beta decays and neutrino mass

    SciTech Connect

    Dvornický, Rastislav; Šimkovic, Fedor

    2015-10-28

    The measurement of the electron energy spectrum in single β decays close to the endpoint provides a direct determination of the neutrino masses. The most sensitive experiments use β decays with low Q value, e.g. KATRIN (tritium) and MARE (rhenium). We present the theoretical spectral shape of electrons emitted in the first, second, and fourth unique forbidden β decays. Our findings show that the Kurie functions for these unique forbidden β transitions are linear in the limit of massless neutrinos like the Kurie function of the allowed β decay of tritium.

  14. Higgs decays and brane gravi-vectors

    SciTech Connect

    Clark, T. E.; Liu Boyang; Love, S. T.; Xiong, C.; Veldhuis, T. ter

    2008-10-01

    Higgs boson decays in flexible brane world models with stable, massive gravi-vectors are considered. Such vectors couple bilinearly to the standard model fields through either the standard model energy-momentum tensor, the weak hypercharge field strength, or the Higgs scalar. The role of the coupling involving the extrinsic curvature is highlighted. It is found that within the presently allowed parameter space, the decay rate of the Higgs into two gravi-vectors (which would appear as an invisible Higgs decay) can be comparable to the rate for any of the standard model decay modes.

  15. Can neutrino decay-driven mock gravity save hot dark matter?

    NASA Technical Reports Server (NTRS)

    Splinter, Randall J.; Melott, Adrian L.

    1992-01-01

    The radiative decay of a 30 eV neutrino with a lifetime of order 10 exp 23-24 s has recently been shown to yield a satisfactory explanation of a wide range of problems in astrophysics. In this paper, it is investigated whether the photon flux generated by the radiative decay of a massive neutrino is capable of generating sufficient radiation pressure to cause a 'mock gravitational' collapse of primordial hydrogen clouds. It is shown that when using neutral hydrogen as a source of opacity for mock gravity the time scale for mock gravitational collapse is significantly larger than the expansion time scale. Thus, the model fails as a source of galactic seed perturbations. Furthermore, it is argued that nonlinear feedback mechanisms will be unable to increase the collapse rate of the cloud under mock gravity.

  16. Analysis of the B{yields}K{sub 2} (1430) l{sup +}l{sup -} decay

    SciTech Connect

    Choudhury, S. R.; Cornell, A. S.; Gaur, Naveen

    2010-05-01

    We present an analysis of the decay process B{yields}K{sub 2}(1430)l{sup +}l{sup -}, where this process has all the features of the related and well investigated process B{yields}K*(890)l{sup +}l{sup -}, with theoretically comparable branching ratios. The differential decay rate as well as the forward-backward asymmetry are worked out, where the sensitivity of these to possible right-handed couplings for the related b{yields}s radiative decay are also investigated.

  17. Measuring the two-photon decay width of intermediate-mass Higgs bosons at a photon-photon collider

    SciTech Connect

    Ohgaki, T.; Takahashi, T.; Watanabe, I.

    1997-08-01

    The feasibility of a measurement of the partial decay width of the intermediate-mass Higgs boson into two photons at a photon-photon collider is studied by a simulation. The QCD radiative correction for quark pair background processes is taken into account for the realistic background estimation. It is found that the two-photon decay width can be measured with the statistical error of 7.6{percent} with about one year of experiment. The impact of the measurement of the two-photon decay width to look for the new physics beyond is demonstrated. {copyright} {ital 1997} {ital The American Physical Society}

  18. Space Radiation

    NASA Technical Reports Server (NTRS)

    Wu, Honglu

    2006-01-01

    Astronauts receive the highest occupational radiation exposure. Effective protections are needed to ensure the safety of astronauts on long duration space missions. Increased cancer morbidity or mortality risk in astronauts may be caused by occupational radiation exposure. Acute and late radiation damage to the central nervous system (CNS) may lead to changes in motor function and behavior, or neurological disorders. Radiation exposure may result in degenerative tissue diseases (non-cancer or non-CNS) such as cardiac, circulatory, or digestive diseases, as well as cataracts. Acute radiation syndromes may occur due to occupational radiation exposure.

  19. Radioactive Decay: Audio Data Collection

    ERIC Educational Resources Information Center

    Struthers, Allan

    2009-01-01

    Many phenomena generate interesting audible time series. This data can be collected and processed using audio software. The free software package "Audacity" is used to demonstrate the process by recording, processing, and extracting click times from an inexpensive radiation detector. The high quality of the data is demonstrated with a simple…

  20. Theory Of Radiation-Induced Attenuation In Optical Fibers

    NASA Technical Reports Server (NTRS)

    Liu, Tsuen-Hsi; Johnston, Alan R.

    1996-01-01

    Improved theory of radiation-induced attenuation of light in optical fibers accounts for effects of dose rates. Based on kinetic aspects of fundamental physics of color centers induced in optical fibers by radiation. Induced attenuation is proportional to density of color centers, and part of this density decays by thermal-annealing/recombination process after irradiation.

  1. Radiological Dispersion Devices and Basic Radiation Science

    ERIC Educational Resources Information Center

    Bevelacqua, Joseph John

    2010-01-01

    Introductory physics courses present the basic concepts of radioactivity and an overview of nuclear physics that emphasizes the basic decay relationship and the various types of emitted radiation. Although this presentation provides insight into radiological science, it often fails to interest students to explore these concepts in a more rigorous…

  2. Properties of a Decaying Sunspot

    NASA Astrophysics Data System (ADS)

    Balthasar, H.; Beck, C.; Gömöry, P.; Muglach, K.; Puschmann, K. G.; Shimizu, T.; Verma, M.

    A small decaying sunspot was observed with the Vacuum Tower Telescope (VTT) on Tenerife and the Japanese Hinode satellite. We obtained full Stokes scans in several wavelengths covering different heights in the solar atmosphere. Imaging time series from Hinode and the Solar Dynamics Observatory (SDO) complete our data sets. The spot is surrounded by a moat flow, which persists also on that side of the spot where the penumbra already had disappeared. Close to the spot, we find a chromospheric location with downflows of more than 10 km s^{-1} without photospheric counterpart. The height dependence of the vertical component of the magnetic field strength is determined in two different ways that yielded different results in previous investigations. Such a difference still exists in our present data, but it is not as pronounced as in the past.

  3. Protonium decay and phase space

    NASA Astrophysics Data System (ADS)

    Vandermeulen, J.

    1992-09-01

    Nucleon-antinucleon at rest presents a variety of channels, where wide mesons often interfere, as shown by the analysis of protonium decay into three pions by the Asterix and Crystal Barrel experiments. A statistical model for emission of the narrow mesons π, η, η' ω, K, ¯K is presented to account for the general profile of the reaction. It is an alternative to a model based on two-doorway state dominance proposed earlier. It allows direct prediction with phenomenological channels, but deals only with branching ratios, not with the detailed structure of the final states. The initial state interactions do not influence the bulk of predictions, although they matter for two-particle branching ratios, which are small. The model is in reasonable agreement with present experimental data and is offered as a standard for comparison with forthcoming results. Some obvious deviations claim for a dynamical explanation.

  4. Decaying neutrinos in galaxy clusters

    NASA Technical Reports Server (NTRS)

    Melott, Adrian L.; Splinter, Randall J.; Persic, Massimo; Salucci, Paolo

    1994-01-01

    Davidsen et al. (1991) have argued that the failure to detect UV photons from the dark matter (DM) in cluster A665 excludes the decaying neutrino hypothesis. Sciama et al. (1993) argued that because of high central concentration the DM in that cluster must be baryonic. We study the DM profile in clusters of galaxies simulated using the Harrison-Zel'dovich spectrum of density fluctuations, and an amplitude previously derived from numerical simulations (Melott 1984b; Anninos et al. 1991) and in agreement with microwave background fluctuations (Smoot et al. 1992). We find that with this amplitude normalization cluster neutrino DM densities are comparable to observed cluster DM values. We conclude that given this normalization, the cluster DM should be at least largely composed of neutrinos. The constraint of Davidsen et al. can be somewhat weakened by the presence of baryonic DM; but it cannot be eliminated given our assumptions.

  5. Decaying neutrinos in galaxy clusters

    NASA Technical Reports Server (NTRS)

    Melott, Adrian L.; Splinter, Randall J.; Persic, Massimo; Salucci, Paolo

    1993-01-01

    The DM profile in clusters of galaxies was studied and simulated using the Harrison-Zel'dovich spectrum of density fluctuations, and an amplitude previously derived from numerical simulations and in agreement with microwave background fluctuations. Neutrino DM densities, with this amplitude normalization cluster, are comparable to observed cluster DM values. It was concluded that given this normalization, the cluster DM should be al least largely composed of neutrinos. The constraint of Davidson et al., who argued that the failure to detect uv photons from the dark matter (DM) in cluster A665 excludes the decaying neutrino hypothesis, could be somewhat weakened by the presence of baryonic DM; but it cannot be eliminated given our assumptions.

  6. New Physics in B decays

    NASA Astrophysics Data System (ADS)

    Crivellin, Andreas

    2016-04-01

    While the LHC did not observe direct evidence for physics beyond the standard model, indirect hints for new physics were uncovered in the flavour sector in the decays B → K*µ+ µ-, B → Kµ+ µ-/B → Ke+e-, Bs → øµ+µ-, B → D(*) τv and h → τ±µ∓. Each observable deviates from the SM predictions at the 2 - 3σ level only, but combining all b → sµ+µ- data via a global fit, one finds 4 - 5 σ difference for NP compared to the SM and combining B → D* τv with B → Dτv one obtains 3:9 σ. While B → D(*) τv and h → τv can be naturally explained by an extended Higgs sector, the b → sµ+µ- anomalies point at a Z' gauge boson. However, it is also possible to explain B → D(*) τv and b → sµ+ µ- simultaneously with leptoquarks while their effect in h → τ±µ∓ is far too small to account for current data. Combining a 2HDM with a gauged Lµ - Lτ symmetry allows for explaining the b → sµ+ µ- anomalies in combination with h → τ±µ∓, predicting interesting correlations with τ → 3µ. In the light of these deviations from the SM we also discuss the possibilities of observing lepton flavour violating B decays (e.g. B → K(*) τ±µ∓ and Bs → τ±µ∓).

  7. Nonradiative decay mechanisms of complexed indole derivatives studied by time-resolved fluorescence

    NASA Astrophysics Data System (ADS)

    Schauerte, Joseph A.; Gafni, Ari

    1990-05-01

    Ground and excited state characteristics of substituted indole derivatives reveal a sensitivity of indoles' electronic properties to the nature and location of substitutions on the indole ring. These substitutions affect both the nature of the excited electronic state and the susceptibility of this state to non-radiative decay processes. A number of mechanisms that deactivate the excited state have been identified including intersystem crossing, electron photoejection into polar solvents, and >N-H dissociation in polar solvents (see Glasser & Lami,1986) . While the >N-H group has been implicated in non-radiative decay processes in polar solvents, covalent substitutions elsewhere on the indole molecule may modulate the importance of this site in non-radiative decay mechanisms or alternatively these substitutions may introduce new deactivation mechanisms. Additionally, complexes formed between indole derivatives and β-cyclodextrin cavities show different sensitivity to excited state deactivation mechanisms dependent upon the location and nature of the covalent substitution. We have investigated the excited states of some indole derivatives substituted at position 5, para to the >N-H group on the benzyl ring, to determine the effect of such covalent substitutions on the fluorescence emission characteristics of the indole ring as well as on its susceptibility to alternate excited state decay mechanisms.

  8. Decaying radiolabelled lymphocytes and method of using same background of the invention

    SciTech Connect

    Chambers, G.P.

    1994-12-30

    Decaying radiolabelled lymphocytes and a method of using same are disclosed. A radiolabelled T-cell lymphocyte including a T-cell containing a Beta-emitting isotope which decays to an alpha-emitting isotope is provided. Alternatively, the T-cell may contain a Beta-emitting isotope which decays one of an x-ray and gamma-emitting isotope. A therapeutic radioisotope treatment method includes the steps of removing a cancerous nodule containing T-cells from a mammal, introducing into the T-cells a Beta-emitting isotope which decays to an alpha-emitting isotope and infusing the T-cells containing the Beta-emitting isotope which decays to an alpha-emitting isotope into the mammal. As an alternative, the treatment method may introduce into the T-cells a Beta-emitting isotope which decays to an x-ray or gamma-emitting isotope. Then, according to the alternative method, after the radioactive T- cells are infused into the mammal, the patient is monitored with a radiation detector to determine the location of T-cells containing the isotopes.

  9. Sunset decay of the convective turbulence with Large-Eddy Simulation under realistic conditions

    NASA Astrophysics Data System (ADS)

    Rizza, U.; Miglietta, M. M.; Degrazia, G. A.; Acevedo, O. C.; Marques Filho, E. P.

    2013-10-01

    Large-Eddy Simulation is performed for a single day from the Cooperative Atmosphere-Surface Exchange Study (CASES-99) field program. This study investigates an observed case of evening transition boundary layer over land. Parameters of the ambient atmosphere in the LES-decay studies conducted so far were typically prescribed in an idealized form. To provide suitable data under the wide range of the PBL weather conditions, the LES should be able to adequately reproduce the PBL turbulence dynamics including-if possible-baroclinicity, radiation, large scale advection and not only be related to a decreasing surface heating. In addition LES-decay studies usually assume that the sensible heat flux decreases instantaneously or with a very short time scale. The main purpose of this investigation is to study the decay of boundary-layer average turbulent kinetic energy at sunset with Large-Eddy Simulation that is forced with realistic environment conditions. This allows investigating the Turbulent Kinetic Energy decay over the realistic time scale that is observed in the atmosphere. During the intermediate and last stage of decay of the boundary-layer average Turbulent Kinetic Energy the exponents of the decay power law t go from 2 to 6, as evidenced by experimental results and recent analytical modeling in the surface layer.

  10. Localized surface plasmon-influenced fluorescence decay in dye-doped metallo-dielectric opals

    NASA Astrophysics Data System (ADS)

    Rout, Dipak; Vijaya, R.

    2016-01-01

    Well-ordered opaline photonic crystals are grown by inward growing self-assembly method from Rhodamine B dye-doped polystyrene colloids. Subsequent to self-assembly, the crystals are infiltrated with gold nanoparticles of 40 nm diameter. Measurements of the stopband features and photoluminescence intensity from these crystals are supplemented by fluorescence decay time analysis. The fluorescence decay times from the dye-doped photonic crystals before and after the infiltration are dramatically different from each other. A lowered fluorescence decay time was observed for the case of gold infiltrated crystal along with an enhanced emission intensity. Double-exponential decay nature of the fluorescence from the dye-doped crystal gets converted into single-exponential decay upon the infiltration of gold nanoparticles due to the resonant radiative process resulting from the overlap of the surface plasmon resonance with the emission spectrum. The influence of localized surface plasmon due to gold nanoparticles on the increase in emission intensity and decrease in decay time of the emitters is established.

  11. Inclusive gamma-ray spectra from psi/3095/ and psi-prime/3684/ decays

    NASA Technical Reports Server (NTRS)

    Biddick, C. J.; Burnett, T. H.; Masek, G. E.; Miller, E. S.; Smith, J. G.; Stronski, J. P.; Sullivan, M. K.; Vernon, W.; Badtke, D. H.; Barnett, B. A.

    1977-01-01

    Inclusive gamma-ray experiments were carried out in a e(+)e(-) colliding-beam apparatus with NaI(Tl) arrays as detectors. The inclusive gamma-ray spectra, after cosmic-ray background subtraction, are shown as histograms for the decays of the psi(3095) and psi-prime(3684). The psi spectrum has no significant narrow structure, while the psi-prime spectrum shows at least four peaks. Three major radiative decays of the psi-prime(3684) are found, and their respective branching fractions are computed.

  12. Mixed incineration of RAIW and liquid scintillator waste after storage for decay

    SciTech Connect

    Naba, K.; Nakazato, K.; Kataoka, K.; Imao, K.

    1993-12-31

    Most medical radioactive waste is combustible after radioactive decay. Moreover mixed incineration of LLW with biomedical radioactive waste will lessen radiation exposure to the public. This paper describes the total system flowsheet for the processing of liquid scintillator wastes and radioimmunoassay tube wastes containing iodine 125 (after a two-year storage for decay). The process was tested with a 60 kg/hr capacity incinerator from 1987 to 1991; this has been upgraded to a 150 kg/hr incinerator which is used for nonradioactive biomedical waste incineration as well.

  13. NuDat 2.0: Nuclear Structure and Decay Data on the Internet

    SciTech Connect

    Sonzogni, A.A.

    2005-05-24

    NuDat 2.0 is a software product developed by the National Nuclear Data Center. It provides an interface between web users and several NNDC nuclear structure and decay databases. NuDat 2.0 can be used to search for ground and excited states level properties, gamma-ray information, and decay radiation information. In addition to the search capabilities, an interactive chart of nuclei is displayed. Different examples highlighting NuDat 2 search capabilities and display options are presented.

  14. Estimation of heat generation by radioactive decay of some phosphate rocks in Egypt.

    PubMed

    Din, Khaled Salahel

    2009-11-01

    Radiogenic heat production data for phosphate rocks outcropping on the three main areas Eastern Desert, Western Desert and Nile Valley are presented. They were derived from uranium, thorium and potassium concentration measurements of gamma radiation originating from the decay of (214)Bi ((238)U series), (208)Tl ((232)Th series) and the primary decay of (40)K. A low radioactive heat production rate (0.32+/-0.1 microWm(-3)) was found for Wadi Hegaza, whereas the highest value (19+/-4.1 microWm(-3)) was found for Gabel Anz, Eastern Desert of Egypt.

  15. A Search for the Rare Decay B0 → γγ

    SciTech Connect

    Ruland, Andrew Michael

    2010-05-01

    This thesis describes a search for the rare radiative decay B0 → γγ, where the charged congugate mode is implied throughout. These decays are highly suppressed in the Standard Model where the branching fraction is expected to be of order 10-8. In some new physics scenarios this could be enhanced by up to an order of magnitude to 10-7. Therefore an observation of a significant signal above the Standard Model prediction could be a sign of new physics.

  16. beta. -decay asymmetry of the free neutron

    SciTech Connect

    Bopp, P.; Dubbers, D.; Klemt, E.; Last, J.; Schuetze, H.; Weibler, W.; Freedman, S.J.; Schaerpf, O.

    1983-01-01

    The ..beta..-decay of polarized neutrons has been studied with the new superconducting spectrometer PERKEO at the ILL. The energy dependence of the ..beta..-decay asymmetry has been measured for the first time. From the measured ..beta..-asymmetry parameter we obtain a new value for the ratio of weak coupling constants g/sub A//g/sub V/. 11 references.

  17. QCD in heavy quark production and decay

    SciTech Connect

    Wiss, J.

    1997-06-01

    The author discusses how QCD is used to understand the physics of heavy quark production and decay dynamics. His discussion of production dynamics primarily concentrates on charm photoproduction data which are compared to perturbative QCD calculations which incorporate fragmentation effects. He begins his discussion of heavy quark decay by reviewing data on charm and beauty lifetimes. Present data on fully leptonic and semileptonic charm decay are then reviewed. Measurements of the hadronic weak current form factors are compared to the nonperturbative QCD-based predictions of Lattice Gauge Theories. He next discusses polarization phenomena present in charmed baryon decay. Heavy Quark Effective Theory predicts that the daughter baryon will recoil from the charmed parent with nearly 100% left-handed polarization, which is in excellent agreement with present data. He concludes by discussing nonleptonic charm decay which is traditionally analyzed in a factorization framework applicable to two-body and quasi-two-body nonleptonic decays. This discussion emphasizes the important role of final state interactions in influencing both the observed decay width of various two-body final states as well as modifying the interference between interfering resonance channels which contribute to specific multibody decays. 50 refs., 77 figs.

  18. Spectroscopy and decays of charm and bottom

    SciTech Connect

    Butler, J.N.

    1997-10-01

    After a brief review of the quark model, we discuss our present knowledge of the spectroscopy of charm and bottom mesons and baryons. We go on to review the lifetimes, semileptonic, and purely leptonic decays of these particles. We conclude with a brief discussion B and D mixing and rare decays.

  19. Addressing Tooth Decay in Head Start Children

    ERIC Educational Resources Information Center

    Knowlden, Adam P.; Hill, Lawrence F.; Alles-White, Monica L.; Cottrell, Randall R.

    2012-01-01

    Tooth decay is the most prevalent chronic disease of childhood. Oral health education and dental services are crucial to reducing the number of children afflicted with dental cavities. Due to limited access to preventative care, Head Start children are particularly vulnerable to tooth decay. This article outlines practical implications of a…

  20. Crystal Ball results on tau decays

    SciTech Connect

    Lowe, S.T.

    1987-10-01

    This report reviews measurements and upper limit determinations for a number of exclusive 1-prong tau decay modes using the Crystal Ball detector. These results are important input to the apparent discrepancy between the topological and sum-of-exclusive branching fractions in 1-prong tau decays.

  1. Radiation dose estimates for radiopharmaceuticals

    SciTech Connect

    Stabin, M.G.; Stubbs, J.B.; Toohey, R.E.

    1996-04-01

    Tables of radiation dose estimates based on the Cristy-Eckerman adult male phantom are provided for a number of radiopharmaceuticals commonly used in nuclear medicine. Radiation dose estimates are listed for all major source organs, and several other organs of interest. The dose estimates were calculated using the MIRD Technique as implemented in the MIRDOSE3 computer code, developed by the Oak Ridge Institute for Science and Education, Radiation Internal Dose Information Center. In this code, residence times for source organs are used with decay data from the MIRD Radionuclide Data and Decay Schemes to produce estimates of radiation dose to organs of standardized phantoms representing individuals of different ages. The adult male phantom of the Cristy-Eckerman phantom series is different from the MIRD 5, or Reference Man phantom in several aspects, the most important of which is the difference in the masses and absorbed fractions for the active (red) marrow. The absorbed fractions for flow energy photons striking the marrow are also different. Other minor differences exist, but are not likely to significantly affect dose estimates calculated with the two phantoms. Assumptions which support each of the dose estimates appears at the bottom of the table of estimates for a given radiopharmaceutical. In most cases, the model kinetics or organ residence times are explicitly given. The results presented here can easily be extended to include other radiopharmaceuticals or phantoms.

  2. Radiation Exposure

    MedlinePlus

    Radiation is energy that travels in the form of waves or high-speed particles. It occurs naturally in sunlight. Man-made radiation is used in X-rays, nuclear weapons, nuclear power plants and cancer treatment. If you are exposed to small amounts of radiation over a ...

  3. Stick slip, charge separation and decay

    USGS Publications Warehouse

    Lockner, D.A.; Byerlee, J.D.; Kuksenko, V.S.; Ponomarev, A.V.

    1986-01-01

    Measurements of charge separation in rock during stable and unstable deformation give unexpectedly large decay times of 50 sec. Time-domain induced polarization experiments on wet and dry rocks give similar decay times and suggest that the same decay mechanisms operate in the induced polarization response as in the relaxation of charge generated by mechanical deformation. These large decay times are attributed to electrochemical processes in the rocks, and they require low-frequency relative permittivity to be very large, in excess of 105. One consequence of large permittivity, and therefore long decay times, is that a significant portion of any electrical charge generated during an earthquake can persist for tens or hundreds of seconds. As a result, electrical disturbances associated with earthquakes should be observable for these lengths of time rather than for the milliseconds previously suggested. ?? 1986 Birka??user Verlag.

  4. Searching for displaced Higgs boson decays

    NASA Astrophysics Data System (ADS)

    Csáki, Csaba; Kuflik, Eric; Lombardo, Salvator; Slone, Oren

    2015-10-01

    We study a simplified model of the Standard Model (SM) Higgs boson decaying to a degenerate pair of scalars which travel a macroscopic distance before decaying to SM particles. This is the leading signal for many well-motivated solutions to the hierarchy problem that do not propose additional light colored particles. Bounds for displaced Higgs boson decays below 10 cm are found by recasting existing tracker searches from Run I. New tracker search strategies, sensitive to the characteristics of these models and similar decays, are proposed with sensitivities projected for Run II at √{s }=13 TeV . With 20 fb-1 of data, we find that Higgs branching ratios down to 2 ×1 0-4 can be probed for centimeter decay lengths.

  5. Neutron Decay with PERC: a Progress Report

    NASA Astrophysics Data System (ADS)

    Konrad, G.; Abele, H.; Beck, M.; Drescher, C.; Dubbers, D.; Erhart, J.; Fillunger, H.; Gösselsberger, C.; Heil, W.; Horvath, M.; Jericha, E.; Klauser, C.; Klenke, J.; Märkisch, B.; Maix, R. K.; Mest, H.; Nowak, S.; Rebrova, N.; Roick, C.; Sauerzopf, C.; Schmidt, U.; Soldner, T.; Wang, X.; Zimmer, O.; Perc Collaboration

    2012-02-01

    The PERC collaboration will perform high-precision measurements of angular correlations in neutron beta decay at the beam facility MEPHISTO of the Forschungs-Neutronenquelle Heinz Maier-Leibnitz in Munich, Germany. The new beam station PERC, a clean, bright, and versatile source of neutron decay products, is designed to improve the sensitivity of neutron decay studies by one order of magnitude. The charged decay products are collected by a strong longitudinal magnetic field directly from inside a neutron guide. This combination provides the highest phase space density of decay products. A magnetic mirror serves to perform precise cuts in phase space, reducing related systematic errors. The new instrument PERC is under development by an international collaboration. The physics motivation, sensitivity, and applications of PERC as well as the status of the design and preliminary results on uncertainties in proton spectroscopy are presented in this paper.

  6. Constraining weak annihilation using semileptonic D decays

    SciTech Connect

    Ligeti, Zoltan; Luke, Michael; Manohar, Aneesh V.

    2010-08-01

    The recently measured semileptonic D{sub s} decay rate can be used to constrain weak annihilation (WA) effects in semileptonic D and B decays. We revisit the theoretical predictions for inclusive semileptonic D{sub (s)} decays using a variety of quark mass schemes. The most reliable results are obtained if the fits to B decay distributions are used to eliminate the charm quark mass dependence, without using any specific charm mass scheme. Our fit to the available data shows that WA is smaller than commonly assumed. There is no indication that the WA octet contribution (which is better constrained than the singlet contribution) dominates. The results constrain an important source of uncertainty in the extraction of |V{sub ub}| from inclusive semileptonic B decays.

  7. Leptonic and semileptonic decays of B mesons

    NASA Astrophysics Data System (ADS)

    Dingfelder, Jochen; Mannel, Thomas

    2016-07-01

    Semileptonic decays are ideally suited to study the weak interaction as well as strong interaction effects in B -meson decays. In the last decade, precision studies of semileptonic B decays have been made possible by the large samples of B mesons collected at the B factories KEKB in Japan and PEP-II in the USA. Measurements of the charged-current semileptonic transitions b →q ℓν (q =u , c ) allow for a determination of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix elements Vc b and Vu b and the masses of the b and c quarks, which are fundamental parameters of the standard model of particle physics. The values of |Vc b| and |Vu b| are determined from measurements of inclusive B decays in combination with calculations of partial decay rates or from exclusive decays combined with theoretical predictions of hadronic form factors. Purely leptonic B decays B →ℓν (ℓ=e , μ , τ ) also provide access to |Vu b|. They are theoretically simpler, but the available signal samples are still small. Decays involving a τ lepton, B →τ ν and B →D(*)τ ν , are sensitive to new physics, in particular, to charged Higgs bosons in models with an extended Higgs sector, and provide a window to the physics of the third generation. In this article, the measurements and theoretical descriptions of charged-current leptonic and semileptonic B decays and the status of |Vc b| and |Vu b| determinations are reviewed. An overview of the theoretical approaches and the experimental techniques used in the study of these decays is also provided.

  8. Radiation Proctopathy

    PubMed Central

    Grodsky, Marc B.; Sidani, Shafik M.

    2015-01-01

    Radiation therapy is a widely utilized treatment modality for pelvic malignancies, including prostate cancer, rectal cancer, and cervical cancer. Given its fixed position in the pelvis, the rectum is at a high risk for injury secondary to ionizing radiation. Despite advances made in radiation science, up to 75% of the patients will suffer from acute radiation proctitis and up to 20% may experience chronic symptoms. Symptoms can be variable and include diarrhea, bleeding, incontinence, and fistulization. A multitude of treatment options exist. This article summarizes the latest knowledge relating to radiation proctopathy focusing on the vast array of treatment options. PMID:26034407

  9. Radiation proctopathy.

    PubMed

    Grodsky, Marc B; Sidani, Shafik M

    2015-06-01

    Radiation therapy is a widely utilized treatment modality for pelvic malignancies, including prostate cancer, rectal cancer, and cervical cancer. Given its fixed position in the pelvis, the rectum is at a high risk for injury secondary to ionizing radiation. Despite advances made in radiation science, up to 75% of the patients will suffer from acute radiation proctitis and up to 20% may experience chronic symptoms. Symptoms can be variable and include diarrhea, bleeding, incontinence, and fistulization. A multitude of treatment options exist. This article summarizes the latest knowledge relating to radiation proctopathy focusing on the vast array of treatment options. PMID:26034407

  10. B, D and K Decays

    SciTech Connect

    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.

    2008-03-07

    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.

  11. Doses from radiation exposure.

    PubMed

    Menzel, H-G; Harrison, J D

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effective dose. In preparation for the calculation of new dose coefficients, Committee 2 and its task groups have provided updated nuclear decay data (ICRP Publication 107) and adult reference computational phantoms (ICRP Publication 110). New dose coefficients for external exposures of workers are complete (ICRP Publication 116), and work is in progress on a series of reports on internal dose coefficients to workers from inhaled and ingested radionuclides. Reference phantoms for children will also be provided and used in the calculation of dose coefficients for public exposures. Committee 2 also has task groups on exposures to radiation in space and on the use of effective dose.

  12. In-flight decay spectroscopy of exotic light nuclei

    SciTech Connect

    Charity, R. J.

    2012-11-20

    In-flight-decay spectroscopy is discussed, including its advantages and disadvantages. In particular the use of in-flight-decay spectroscopy for the study of two-proton decay along isobaric multiplets in highlighted.

  13. Tau Decays at BaBar

    SciTech Connect

    Hast, Carsten; /SLAC

    2009-01-22

    Recent results of tau lepton decay studies based on luminosities between 350 fb{sup -1} and 469 fb{sup -1} collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory are presented. The analyses reported here are Charged Current Lepton Universality and measurements of |V{sub us}| using {tau}{sup -} {yields} e{sup -}{bar {nu}}{sub e}{nu}{sub {tau}}, {mu}{sup -}{bar {nu}}{sub {mu}}{nu}{sub {tau}}, {pi}{sup -} {nu}{sub {tau}}, and K{sup -}{nu}{sub {tau}} decays, as well as searches for Second Class Currents in {tau}{sup -} {yields} {omega}{pi}{sup -}{nu}{sub {tau}} decays, studies of Lepton Flavor Violations, and a tau mass measurement and CPT-Test. If not explicitly mentioned, charge conjugate decay modes are also implied. decays, as well as searches for Second Class Currents in {tau}{sup -} {yields} {omega}{pi}{sup -}{nu}{sub {tau}} decays, studies of Lepton Flavor Violations, and a tau mass measurement and CPT-Test. If not explicitly mentioned, charge conjugate decay modes are also implied.

  14. Ring current proton decay by charge exchange

    NASA Technical Reports Server (NTRS)

    Smith, P. H.; Hoffman, R. A.; Fritz, T.

    1975-01-01

    Explorer 45 measurements during the recovery phase of a moderate magnetic storm have confirmed that the charge exchange decay mechanism can account for the decay of the storm-time proton ring current. Data from the moderate magnetic storm of 24 February 1972 was selected for study since a symmetrical ring current had developed and effects due to asymmetric ring current losses could be eliminated. It was found that after the initial rapid decay of the proton flux, the equatorially mirroring protons in the energy range 5 to 30 keV decayed throughout the L-value range of 3.5 to 5.0 at the charge exchange decay rate calculated by Liemohn. After several days of decay, the proton fluxes reached a lower limit where an apparent equilibrium was maintained, between weak particle source mechanisms and the loss mechanisms, until fresh protons were injected into the ring current region during substorms. While other proton loss mechanisms may also be operating, the results indicate that charge exchange can entirely account for the storm-time proton ring current decay, and that this mechanism must be considered in all studies involving the loss of proton ring current particles.

  15. Beta decay of 187Re and cosmochronology

    NASA Astrophysics Data System (ADS)

    Ashktorab, K.; Jänecke, J. W.; Becchetti, F. D.

    1993-06-01

    Uncertainties which limit the use of the 187-187Os isobaric pair as a cosmochronometer for the age of the galaxy and the universe include those of the partial half-lives of the continuum and bound-state decays of 187Re. While the total half-life of the decay is well established, the partial half-life for the continuum decay is uncertain, and several previous measurements are not compatible with each other. A high-temperature quartz proportional counter has been used in this work to remeasure the continuum decay of 187Re by introducing a metallo-organic rhenium compound into the counting gas. The measured beta end-point energy for the continuum decay of neutral 187Re to singly ionized 187Os of 2.70+/-0.09 keV agrees with earlier results. However, the present half-life measurement of (45+/-3) Gyr agrees within the quoted uncertainties only with the earlier measurement of Payne [Ph.D. thesis, University of Glasgow, 1965 (unpublished)] and Drever (private communication). The new half-life for the continuum decay and the total half-life of (43.5+/-1.3) Gyr, as reported by Linder et al. [Nature (London) 320, 246 (1986)] yield a branching ratio for the bound-state decay into discrete atomic states of (3+/-6)%. This is in agreement with the most recent calculated theoretical branching ratio of approximately 1%.

  16. Particle physics: CP violation in hyperon decays

    SciTech Connect

    Longo, Michael J.

    2000-10-31

    The primary research activities under this grant were in E871 (HyperCP) at Fermilab, a search for CP violation in hyperon decays which completed data taking in January, 2000. HyperCP is an experiment designed to perform a sensitive search for direct CP violation in the decays of cascade ({Xi}) and {Lambda} hyperons by looking for an asymmetry between particle and antiparticle decay parameters. The experiment is expected to achieve a sensitivity {approx}10{sup -4} in the decay parameters. Standard model predictions for this CP-violating asymmetry range from 0.3 to 5 x 10{sup -4}. A difference between the decay parameters for particle and antiparticle is direct evidence that CP symmetry is violated. A non-zero asymmetry would be the first evidence for CP violation outside of the K{sup o} system. Recent results from KTeV indicate a direct CP violation in K{sup o} decays, which suggests that CP violation will appear in other decays. In addition, we will look at a number of rare hyperon decays involving muons. These probe important new physics topics such as Majorana neutrinos and lepton number violating processes. The latter are of great current interest because new evidence for neutrino oscillations indicate lepton flavor violation does occur. Our data will lead to an improvement in the limits on branching ratios for these processes typically by three to four orders-of-magnitude. The muon detector construction and data resulting from it have been the responsibility of the Michigan group. We are now leading the analysis of the rare muon-related decay modes, and were responsible for the muon system and beam monitor upgrades for the 1999 run.

  17. Radiation Chemistry

    NASA Astrophysics Data System (ADS)

    Wojnárovits, L.

    Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.

  18. Radionuclide sources and radioactive decay figures pertinent to the Hanford Environmental Dose Reconstruction Project

    SciTech Connect

    Heeb, C.M.

    1991-03-01

    The origin and radioactive decay schemes of radionuclides currently expected to be the major contributors to potential radiation doses that populations might have received as a result of nuclear operations at the Hanford Site since 1944 are identified and illustrated in this report. The reactions considered include actinide neutron capture and decay sequences, fission product decays, and neutron activation reactions. It is important to note that the radioactive half-life of a given nuclide does not, by itself, fully determine the significance of a given radionuclide as a potential source term. This report does not address environmental transport mechanisms, behavior in the environment, or radiological dose impact of any of the radionuclides shown. 1 ref., 10 figs.

  19. Z and Z' decays with and without FCNC in 331 models

    NASA Astrophysics Data System (ADS)

    Carcamo, A.; Martínez, R.; Ochoa, F.

    2006-02-01

    In the context of the 331 models, we consider constraints on the extra neutral boson Z' predicted by the model, where three different quark family assignments are identified. Using the ansatz of Matsuda as an specific texture for the quark mass matrices, we obtain allowed regions associated with the Z-Z' mixing angle, the mass of the Z' boson and the parameter β which determines different 331 models. The Z1 and Z2 decays with and without flavor changing are also considered. The flavor changing decays of the Z1 boson into quarks at tree level are highly suppressed by the Z-Z' mixing angle, obtaining the same order of magnitude as the standard model prediction at one-loop level. The Z2 decay widths are calculated with and without flavor changing, where oblique radiative corrections at one loop accounts for about 1%-4% deviations.

  20. Geometrical scaling and modal decay rates in periodic arrays of deeply subwavelength Terahertz resonators

    SciTech Connect

    Isić, Goran Gajić, Radoš

    2014-12-21

    It is well known that due to the high conductivity of noble metals at terahertz frequencies and scalability of macroscopic Maxwell equations, a geometrical downscaling of a terahertz resonator results in the linear upscaling of its resonance frequency. However, the scaling laws of modal decay rates, important for the resonator excitation efficiency, are much less known. Here, we investigate the extent to which the scale-invariance of decay rates is violated due to the finite conductivity of the metal. We find that the resonance quality factor or the excitation efficiency may be substantially affected by scaling and show that this happens as a result of the scale-dependence of the metal absorption rate, while the radiative decay and the dielectric cavity absorption rates are approximately scale-invariant. In particular, we find that by downscaling overcoupled resonators, their excitation efficiency increases, while the opposite happens with undercoupled resonators.

  1. Nudat: Nuclear Structure and Decay Data from the National Nuclear Data Center (NNDC)

    DOE Data Explorer

    NuDat allows users to search and plot nuclear structure and decay data interactively. NuDat was developed by the National Nuclear Data Center (NNDC)but utilizes contributions from physicists around the world. It provides an interface between web users and several databases containing nuclear structure, nuclear decay and some neutron-induced nuclear reaction information. Users can search for nuclear level properties (energy, half-life, spinparity), gamma-ray information (energy, intensity, multipolarity, coincidences), radiation information following nuclear decay (energy, intensity, dose), and neutron-induced reaction data from the BNL-325 book (thermal cross section and resonance integral). The information provided by NuDat 2 can be viewed in tables, level schemes and an interactive chart of nuclides.

  2. Superradiant decay of cyclotron resonance of two-dimensional electron gases.

    PubMed

    Zhang, Qi; Arikawa, Takashi; Kato, Eiji; Reno, John L; Pan, Wei; Watson, John D; Manfra, Michael J; Zudov, Michael A; Tokman, Mikhail; Erukhimova, Maria; Belyanin, Alexey; Kono, Junichiro

    2014-07-25

    We report on the observation of collective radiative decay, or superradiance, of cyclotron resonance (CR) in high-mobility two-dimensional electron gases in GaAs quantum wells using time-domain terahertz magnetospectroscopy. The decay rate of coherent CR oscillations increases linearly with the electron density in a wide range, which is a hallmark of superradiant damping. Our fully quantum mechanical theory provides a universal formula for the decay rate, which reproduces our experimental data without any adjustable parameter. These results firmly establish the many-body nature of CR decoherence in this system, despite the fact that the CR frequency is immune to electron-electron interactions due to Kohn's theorem. PMID:25105654

  3. Correlation between thermoluminescence and radiation damage in bismuth germanate

    SciTech Connect

    Melcher, C.L.

    1985-02-01

    Thermoluminescence properties of bismuth germanate and their relationship to radiation damage characteristics have been investigated. Thermoluminescence and radiation damage in bismuth germanate display several similar properties including similar responses as a function of radiation dose, similar saturation levels, and similar decay times. Also a correlation was found between the thermoluminescence sensitivities and radiation damage sensitivities of four different crystals. The traps responsible for the radiation damage and those which store the thermoluminescence signal appear to be either closely related or actually the same traps. Four trapping centers can be seen in the thermoluminescence glow curves. The depth of the dominant trap is 1.1 eV. 10 references.

  4. Suppressed $B_s$ decays at CDF

    SciTech Connect

    Dorigo, Mirco

    2011-05-01

    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.

  5. B to tau Leptonic and Semileptonic Decays

    SciTech Connect

    Barrett, M.; /Brunel U.

    2011-11-17

    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.

  6. Trap-assisted decay spectroscopy with ISOLTRAP

    NASA Astrophysics Data System (ADS)

    Kowalska, M.; Naimi, S.; Agramunt, J.; Algora, A.; Beck, D.; Blank, B.; Blaum, K.; Böhm, Ch.; Borgmann, Ch.; Breitenfeldt, M.; Fraile, L. M.; George, S.; Herfurth, F.; Herlert, A.; Kreim, S.; Lunney, D.; Minaya-Ramirez, E.; Neidherr, D.; Rosenbusch, M.; Rubio, B.; Schweikhard, L.; Stanja, J.; Zuber, K.

    2012-10-01

    Penning traps are excellent high-precision mass spectrometers for radionuclides. The high-resolving power used for cleaning isobaric and even isomeric contaminants can be exploited to improve decay-spectroscopy studies by delivering purified samples. An apparatus allowing trap-assisted decay spectroscopy has been coupled to the ISOLTRAP mass spectrometer at ISOLDE/CERN. The results from studies with stable and radioactive ions show that the setup can be used to perform decay studies on purified short-lived nuclides and to assist mass measurements.

  7. Spectroscopy of element 115 decay chains.

    PubMed

    Rudolph, D; Forsberg, U; Golubev, P; Sarmiento, L G; Yakushev, A; Andersson, L-L; Di Nitto, A; Düllmann, Ch E; Gates, J M; Gregorich, K E; Gross, C J; Heßberger, F P; Herzberg, R-D; Khuyagbaatar, J; Kratz, J V; Rykaczewski, K; Schädel, M; Åberg, S; Ackermann, D; Block, M; Brand, H; Carlsson, B G; Cox, D; Derkx, X; Eberhardt, K; Even, J; Fahlander, C; Gerl, J; Jäger, E; Kindler, B; Krier, J; Kojouharov, I; Kurz, N; Lommel, B; Mistry, A; Mokry, C; Nitsche, H; Omtvedt, J P; Papadakis, P; Ragnarsson, I; Runke, J; Schaffner, H; Schausten, B; Thörle-Pospiech, P; Torres, T; Traut, T; Trautmann, N; Türler, A; Ward, A; Ward, D E; Wiehl, N

    2013-09-13

    A high-resolution α, x-ray, and γ-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated α-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. 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.

  8. Electrostatic decay in a weakly magnetized plasma.

    PubMed

    Layden, A; Cairns, Iver H; Li, B; Robinson, P A

    2013-05-01

    The kinematics of the electrostatic (ES) decay of a Langmuir wave into a Langmuir wave and an ion sound wave are generalized to a weakly magnetized plasma. Unlike the unmagnetized case, ES decay in a magnetized plasma is always kinematically permitted and can produce daughter Langmuir waves with very small wave numbers, which we demonstrate by quasilinear simulations. The simulations further show that ES decay in magnetized plasmas is consistent with STEREO spacecraft observations of transversely polarized Langmuir waves in the solar wind. PMID:23683206

  9. Charmless and Penguin Decays at CDF

    SciTech Connect

    Dorigo, Mirco; Collaboration, for the CDF

    2010-12-01

    Penguin transitions play a key role in the search of New Physics hints in the heavy flavor sector. During the last decade CDF has been exploring this opportunity with a rich study of two-body charmless decays of neutral B mesons into charged final-state particles. After briefly introducing the aspects of this physics peculiar to the hadron collision environment, I report on two interesting results: the first polarization measurement of the B{sub s}{sup 0} {yields} {phi}{phi} decay and the update of the B{sub (s)}{sup 0} {yields} h{sup +}h{prime}{sup -} decays analysis.

  10. β -decay study of 94Kr

    NASA Astrophysics Data System (ADS)

    Miernik, K.; Rykaczewski, K. P.; Grzywacz, R.; Gross, C. J.; Madurga, M.; Miller, D.; Stracener, D. W.; Batchelder, J. C.; Brewer, N. T.; Cartegni, L.; Fijałkowska, A.; Karny, M.; Korgul, A.; Królas, W.; Mazzocchi, C.; Mendez, A. J., II; Padgett, S. W.; Paulauskas, S. V.; Winger, J. A.; Wolińska-Cichocka, M.; Zganjar, E. F.

    2016-08-01

    β decay of neutron-rich nuclide 94Kr was reinvestigated by means of a high resolution on-line mass separator and β -γ spectroscopy. In total 22 γ -ray transitions were assigned to the decay of 94Kr, and a new isomeric state was identified. The new information allows us to build detailed levels systematics in a chain of odd-odd rubidium isotopes and draw conclusions on nuclear structure for some of the observed states. The discussed level structure affects the evolution of β -decay half-lives for neutron-rich selenium, krypton, and strontium isotopes.

  11. Decay time of type 3 solar bursts

    NASA Technical Reports Server (NTRS)

    Alvarez, H.; Haddock, F. T.

    1973-01-01

    Type 3 solar bursts observed by OGO-5, below 600 kHz, were analyzed. Decay times were measured, and collisional decay times were computed for distances out to 1 AU. By fitting power functions to the computed and observed decay times, and using local plasma hypothesis, it was found that the ratio rho of computed observed values varies with heliocentric radial distance according to a power function rho = 3r to the 0.7th power, assuming fundamental emission, and rho = 2r to the 0.7th power, assuming second harmonic emission.

  12. Rare kaon, muon, and pion decay

    SciTech Connect

    Littenberg, L.

    1998-12-01

    The author discusses the status of and prospects for the study of rare decays of kaons, muons, and pions. Studies of rare kaon decays are entering an interesting new phase wherein they can deliver important short-distance information. It should be possible to construct an alternative unitarity triangle to that determined in the B sector, and thus perform a critical check of the Standard Model by comparing the two. Rare muon decays are beginning to constrain supersymmetric models in a significant way, and future experiments should reach sensitivities which this kind of model must show effects, or become far less appealing.

  13. Spectroscopy of element 115 decay chains.

    PubMed

    Rudolph, D; Forsberg, U; Golubev, P; Sarmiento, L G; Yakushev, A; Andersson, L-L; Di Nitto, A; Düllmann, Ch E; Gates, J M; Gregorich, K E; Gross, C J; Heßberger, F P; Herzberg, R-D; Khuyagbaatar, J; Kratz, J V; Rykaczewski, K; Schädel, M; Åberg, S; Ackermann, D; Block, M; Brand, H; Carlsson, B G; Cox, D; Derkx, X; Eberhardt, K; Even, J; Fahlander, C; Gerl, J; Jäger, E; Kindler, B; Krier, J; Kojouharov, I; Kurz, N; Lommel, B; Mistry, A; Mokry, C; Nitsche, H; Omtvedt, J P; Papadakis, P; Ragnarsson, I; Runke, J; Schaffner, H; Schausten, B; Thörle-Pospiech, P; Torres, T; Traut, T; Trautmann, N; Türler, A; Ward, A; Ward, D E; Wiehl, N

    2013-09-13

    A high-resolution α, x-ray, and γ-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated α-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. 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. PMID:24074079

  14. Three-body decay of many-body resonances

    SciTech Connect

    Jensen, A.S.; Fedorov, D.V.; Fynbo, H.O.U.; Garrido, E.

    2005-10-14

    We use the hyperspherical coordinates to describe decay of many-body resonances. Direct and sequential decay are described by different paths in the distances between the particles. We generalize the WKB expression for the {alpha}-decay width to decay of three charged particles. Decay mechanisms and resonance structures are computed in coordinate space. The energy distributions of the particles after decay are discussed. Moderate s-wave scattering lengths prefer decay via corresponding virtual state possibly leaving unique fingerprints of this reminiscence of the Efimov effect in the decay of excited states. Numerical illustrations are resonances in 6He, 12C, 17Ne.

  15. Nanoscintillators for radiation detection

    NASA Astrophysics Data System (ADS)

    Hall, Ryan Gregory

    In the search for faster, more effective methods for detection of and protection against radiological weapons, advances in materials for radiation detection are a critical component of any successful strategy. This work focuses on producing inexpensive, but highly sensitive, nanoparticle alternatives to existing single-crystal installations. Attention is given to particular types of promising inorganic scintillators: LaF3, yttrium-aluminum-garnet (YAG), and SrF2, each one an inorganic host doped with additional elements that encourage luminescent decay and increase effective Z-value. I examine the possible routes to synthesize these compounds, and the difficulties and benefits of each method. After synthesizing these materials, testing was performed to determine comparative performance against each other and commercial solutions, identify structural and compositional characteristics, and explore routes for fixing the scintillators into a detector assembly. The unifying goal is to develop a scintillating material suitable for consistent dosimetry and radio-isotope identification applications.

  16. The Gas-Cooled Fast Reactor: Report on Safety System Design for Decay Heat Removal

    SciTech Connect

    K. D. Weaver; T. Marshall; T. Y. C. Wei; E. E. Feldman; M. J. Driscoll; H. Ludewig

    2003-09-01

    The gas-cooled fast reactor (GFR) was chosen as one of the Generation IV nuclear reactor systems to be developed based on its excellent potential for sustainability through reduction of the volume and radiotoxicity of both its own fuel and other spent nuclear fuel, and for extending/utilizing uranium resources orders of magnitude beyond what the current open fuel cycle can realize. In addition, energy conversion at high thermal efficiency is possible with the current designs being considered, thus increasing the economic benefit of the GFR. However, research and development challenges include the ability to use passive decay heat removal systems during accident conditions, survivability of fuels and in-core materials under extreme temperatures and radiation, and economical and efficient fuel cycle processes. This report addresses/discusses the decay heat removal options available to the GFR, and the current solutions. While it is possible to design a GFR with complete passive safety (i.e., reliance solely on conductive and radiative heat transfer for decay heat removal), it has been shown that the low power density results in unacceptable fuel cycle costs for the GFR. However, increasing power density results in higher decay heat rates, and the attendant temperature increase in the fuel and core. Use of active movers, or blowers/fans, is possible during accident conditions, which only requires 3% of nominal flow to remove the decay heat. Unfortunately, this requires reliance on active systems. In order to incorporate passive systems, innovative designs have been studied, and a mix of passive and active systems appears to meet the requirements for decay heat removal during accident conditions.

  17. Radiator technology

    NASA Technical Reports Server (NTRS)

    Juhasz, Albert J.

    1993-01-01

    Radiator technology is discussed in the context of the Civilian Space Technology Initiative's (CSTI's) high capacity power-thermal management project. The CSTI project is a subset of a project to develop a piloted Mars nuclear electric propulsion (NEP) vehicle. The following topics are presented in vugraph form: advanced radiator concepts; heat pipe codes and testing; composite materials; radiator design and integration; and surface morphology.

  18. Hawking radiation

    NASA Astrophysics Data System (ADS)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

  19. A website dedicated to ionizing radiation metrology.

    PubMed

    Dulieu, Christophe; Chisté, Vanessa; Bé, Marie-Martine

    2004-01-01

    In order to disseminate information about decay data and their evaluation, as well as other topics in the field of ionizing radiation, the Bureau National de Métrologie-Laboratoire National Henri Becquerel (BNM-LNHB) has published a website. Most of the web pages are concerned with the international working groups in which the BNM-LNHB takes part. In particular, a library of uranium and plutonium spectra is now available, as well as the results of evaluation of decay data of nuclides of special interest.

  20. Curvaton scenarios with inflaton decays into curvatons

    NASA Astrophysics Data System (ADS)

    Byrnes, Christian T.; Cortês, Marina; Liddle, Andrew R.

    2016-09-01

    We consider the possible decay of the inflaton into curvaton particles during reheating and analyze its effect on curvaton scenarios. Typical decay curvatons are initially relativistic then become nonrelativistic, changing the background history of the Universe. We show that this change to the background is the only way in which observational predictions of the scenario are modified. Moreover, once the required amplitude of perturbations is fixed by observation there are no signatures of such decays in other cosmological observables. The decay curvatons can prevent the Universe from becoming dominated by the curvaton condensate, making it impossible to match observations in parts of parameter space. This constrains the branching ratio of the inflaton to curvaton to be less than of order 0.1 typically. If the branching ratio is below about 10-4 it has negligible impact on the model parameter space and can be ignored.

  1. B Decays with tau at Belle

    SciTech Connect

    Hara, Koji

    2010-02-10

    B decays with {tau} are sensitive to a charged Higgs predicted by extensions of the Standard Model such as the Two Higgs Doublet Models and the Minimal Supersymmetric Standard Model. We report measurements of the decays B+->{tau}{sup +}{nu}{sub {tau}}, B->D*{tau}{nu}{sub {tau}} and B->D{tau}{nu}{sub {tau}} using a large data sample of BB-bar pairs collected with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider. We observe a signal of B{sup 0}->D*{sup -}{tau}{sup +}{nu}{sub {tau}} decay with a significance of 5.2 {sigma} and find evidences of B{sup +}->{tau}{sup +}{nu}{sub {tau}} and D-bar{sup 0}{tau}{sup +}{nu}{sub {tau}} decays with significances more than 3 {sigma}.

  2. 7 CFR 51.898 - Decay.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946.... Slight surface development of green mold (Cladosporium) shall not be considered decay....

  3. Rare charm and B decays at CDF

    SciTech Connect

    Julia Thom

    2003-12-15

    We present results on rare charm and B decays using 65pb{sup -1} of data taken with the CDF detector in Run II. Three results are discussed, a measurement of the relative branching ratios {Lambda}(D{sup 0} {yields} K{sup +}K{sup -})/{Lambda}(D{sup 0} {yields} K{pi}) and {Lambda}(D{sup 0} {yields} {pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{pi}) and the direct CP-violating decay rate asymmetry, and a limit on the branching ratio of the FCNC decay D{sup 0} {yields} {mu}{sup +}{mu}{sup -}. We also discuss the prospects for the search for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays.

  4. The decay of highly excited open strings

    NASA Technical Reports Server (NTRS)

    Mitchell, D.; Turok, N.; Wilkinson, R.; Jetzer, P.

    1988-01-01

    The decay rates of leading edge Regge trajectory states are calculated for very high level number in open bosonic string theories, ignoring tachyon final states. The optical theorem simplifies the analysis while enabling identification of the different mass level decay channels. The main result is that (in four dimensions) the greatest single channel is the emission of a single photon and a state of the next mass level down. A simple asymptotic formula for arbitrarily high level number is given for this process. Also calculated is the total decay rate exactly up to N=100. It shows little variation over this range but appears to decrease for larger N. The formalism is checked in examples and the decay rate of the first excited level calculated for open superstring theories. The calculation may also have implications for high spin meson resonances.

  5. LHC prospects for minimal decaying dark matter

    SciTech Connect

    Arcadi, Giorgio; Covi, Laura; Dradi, Federico E-mail: laura.covi@theorie.physik.uni-goettingen.de

    2014-10-01

    We study the possible signals at LHC of the minimal models of decaying dark matter. Those models are characterized by the fact that DM interacts with SM particles through renormalizable coupling with an additional heavier charged state. Such interaction allows to produce a substantial abundance of DM in the early Universe via the decay of the charged heavy state, either in- or out-of-equilibrium. Moreover additional couplings of the charged particle open up decay channels for the DM, which can nevertheless be sufficiently long-lived to be a good DM candidate and within reach of future Indirect Detection observations. We compare the cosmologically favored parameter regions to the LHC discovery reach and discuss the possibility of simultaneous detection of DM decay in Indirect Detection.

  6. Decay of Turbulence at High Reynolds Numbers

    NASA Astrophysics Data System (ADS)

    Sinhuber, Michael; Bodenschatz, Eberhard; Bewley, Gregory P.

    2015-01-01

    Turbulent motions in a fluid decay at a certain rate once stirring has stopped. The role of the most basic parameter in fluid mechanics, the Reynolds number, in setting the decay rate is not generally known. This Letter concerns the high-Reynolds-number limit of the process. In a classical grid-turbulence wind-tunnel experiment that both reaches higher Reynolds numbers than ever before and covers a wide range of them (1 04decay rate with the unprecedented precision of about 2%. Here U is the mean speed of the flow, M is the forcing scale, and ν is the kinematic viscosity of the fluid. We observe that the decay rate is Reynolds-number independent, which contradicts some models and supports others.

  7. Review of modern double beta decay experiments

    SciTech Connect

    Barabash, A. S.

    2015-10-28

    The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T{sub 1/2}(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino (〈m{sub ν}〉 < 0.46 eV) and a coupling constant of Majoron to neutrino (〈g{sub ee}〉 < 1.3 · 10{sup −5}) are obtained. Prospects of search for neutrinoless double beta decay in new experiments with sensitivity to 〈m{sub ν}〉 at the level of ∼ 0.01-0.1 eV are discussed.

  8. Decay heat studies for nuclear energy

    NASA Astrophysics Data System (ADS)

    Algora, A.; Jordan, D.; Taín, J. L.; Rubio, B.; Agramunt, J.; Caballero, L.; Nácher, E.; Perez-Cerdan, A. B.; Molina, F.; Estevez, E.; Valencia, E.; Krasznahorkay, A.; Hunyadi, M. D.; Gulyás, J.; Vitéz, A.; Csatlós, M.; Csige, L.; Eronen, T.; Rissanen, J.; Saastamoinen, A.; Moore, I. D.; Penttilä, H.; Kolhinen, V. S.; Burkard, K.; Hüller, W.; Batist, L.; Gelletly, W.; Nichols, A. L.; Yoshida, T.; Sonzogni, A. A.; Peräjärvi, K.

    2014-01-01

    The energy associated with the decay of fission products plays an important role in the estimation of the amount of heat released by nuclear fuel in reactors. In this article we present results of the study of the beta decay of some refractory isotopes that were considered important contributors to the decay heat in reactors. The measurements were performed at the IGISOL facility of the University of Jyväskylä, Finland. In these studies we have combined for the first time a Penning trap (JYFLTRAP), which was used as a high resolution isobaric separator, with a total absorption spectrometer. The results of the measurements as well as their consequences for decay heat summation calculations are discussed.

  9. Rare Decays at the LHCb Experiment

    NASA Astrophysics Data System (ADS)

    Pescatore, L.

    2015-06-01

    Rare decays of beauty and charm hadrons offer a rich playground to make precise tests of the Standard Model and look for New Physics at the level of quantum corrections. A review of recent LHCb results will be presented.

  10. Evaluation of 235U decay data.

    PubMed

    Xiaolong, Huang; Baosong, Wang

    2009-09-01

    Evaluation of the complete decay scheme and data for (235)U including new measurements are presented in this report; literature data available up to June 2008 are included. The half-life is determined to be (7.04+/-0.01) x 10(8) yr. All known measured gamma-ray absolute intensities have been examined; the gamma-ray emission probability of the reference gamma-ray line of 185.72 keV is recommended to be 57.0+/-0.3%. The calculated internal conversion coefficients and their uncertainties have been used to obtain the complete decay intensity balance. The other decay characteristics are calculated using the ENSDF analysis program. Finally the new decay scheme for (235)U is presented.

  11. Searching for $Z'$ bosons decaying to gluons

    SciTech Connect

    Alwall, Johan; Khader, Mazin; Rajaraman, Arvind; Whiteson, Daniel; Yen, Michael; /UC, Irvine

    2012-02-01

    The production and decay of a new heavy vector boson, a chromophilic Z{prime} vector boson, is described. The chromophilic Z{prime} couples only to two gluons, but its two-body decays are absent, leading to a dominant decay mode of Z{prime} {yields} q{bar q}g. The unusual nature of the interaction predicts a cross-section which grows with m{sub Z{prime}} for a fixed coupling and an accompanying gluon with a coupling that rises with its energy. We study the t{bar t}g decay mode, proposing distinct reconstruction techniques for the observation of an excess and for the measurement of m{sub Z{prime}}. We estimate the sensitivity of current experimental datasets.

  12. Revisiting B→ϕπ decays in the standard model

    NASA Astrophysics Data System (ADS)

    Li, Ying; Lü, Cai-Dian; Wang, Wei

    2009-07-01

    In the standard model, we reinvestigate the rare decay B→ϕπ, which is viewed as an ideal probe to detect the new physics signals. We find that the tiny branching ratio in the naive factorization can be dramatically enhanced by the radiative corrections and the ω-ϕ mixing effect, while the long-distance contributions are negligibly small. Assuming the Cabibbo-Kobayashi-Maskawa angle γ=(58.6±10)° and the mixing angle θ=-(3.0±1.0)°, we obtain the branching ratios of B→ϕπ as Br(B±→ϕπ±)=(3.2-0.7+1.8+0.8-1.2)×10-8 and Br(B0→ϕπ0)=(6.8-0.3+1.0+0.3-0.7)×10-9. If the future experiment reports a branching ratio of (0.2-0.5)×10-7 for B-→ϕπ- decay, it may not be a clear signal for any new physics scenario. In order to discriminate the large new physics contributions from those due to the ω-ϕ mixing, we propose to measure the ratio of branching fractions of the charged and neutral B decay channel. We also study the direct CP asymmetries of these two channels: (-8.0-1.0-0.1+0.9+1.5)% and (-6.3+0.7-2.5-0.5+2.5)% for B±→ϕπ± and B0→ϕπ0, respectively. These asymmetries are dominated by the mixing effect.

  13. The impact of exospheric neutral dynamics on ring current decay

    NASA Astrophysics Data System (ADS)

    Ilie, R.; Liemohn, M. W.; Skoug, R. M.; Funsten, H. O.; Gruntman, M.; Bailey, J. J.; Toth, G.

    2015-12-01

    The geocorona plays an important role in the energy budget of the Earth's inner magnetosphere since charge exchange of energetic ions with exospheric neutrals makes the exosphere act as an energy sink for ring current particles. Long-term ring current decay following a magnetic storm is mainly due to these electron transfer reactions, leading to the formation energetic neutral atoms (ENAs) that leave the ring current system on ballistic trajectories. The number of ENAs emitted from a given region of space depends on several factors, such as the energy and species of the energetic ion population in that region and the density of the neutral gas with which the ions undergo charge exchange. However, the density and structure of the exosphere are strongly dependent on changes in atmospheric temperature and density as well as charge exchange with the ions of plasmaspheric origin, which depletes the geocorona (by having a neutral removed from the system). Moreover, the radiation pressure exerted by solar far-ultraviolet photons pushes the geocoronal hydrogen away from the Earth in an anti-sunward direction to form a tail of neutral hydrogen. TWINS ENA images provide a direct measurement of these ENA losses and therefore insight into the dynamics of the ring current decay through interactions with the geocorona. We assess the influence of geocoronal neutrals on ring current formation and decay by analysis of the predicted ENA emissions using 6 different geocoronal models and simulations from the HEIDI ring current model during storm time. Comparison with TWINS ENA images shows that the location of the peak ENA enhancements is highly dependent on the distribution of geocoronal hydrogen density. We show that the neutral dynamics has a strong influence on the time evolution of the ring current populations as well as on the formation of energetic neutral atoms.

  14. Cosmic strings and baryon decay catalysis

    NASA Technical Reports Server (NTRS)

    Gregory, Ruth; Perkins, W. B.; Davis, A.-C.; Brandenberger, R. H.

    1989-01-01

    Cosmic strings, like monopoles, can catalyze proton decay. For integer charged fermions, the cross section for catalysis is not amplified, unlike in the case of monopoles. The catalysis processes are reviewed both in the free quark and skyrmion pictures and the implications for baryogenesis are discussed. A computation of the cross section for monopole catalyzed skyrmion decay is presented using classical physics. Also discussed are some effects which can screen catalysis processes.

  15. Cosmic string catalysis of skyrmion decay

    NASA Technical Reports Server (NTRS)

    Gregory, Ruth; Davis, Anne-Christine; Brandenberger, Robert

    1988-01-01

    The Callan-Witten picture is developed for monopole catalyzed skyrmion decay in order to analyze the corresponding cosmic string scenario. It is discovered that cosmic strings (both ordinary and superconducting) can catalyze proton decay, but that this catalysis only occurs on the scale of the core of the string. In order to do this we have to develop a vortex model for the superconducting string. An argument is also given for the difference in the enhancement factors for monopoles and strings.

  16. Rare top quark decays in extended models

    SciTech Connect

    Gaitan, R.; Miranda, O. G.; Cabral-Rosetti, L. G.

    2006-09-25

    Flavor changing neutral currents (FCNC) decays t {yields} H0 + c, t {yields} Z + c, and H0 {yields} t + c-bar are discussed in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions where FCNC decays may take place at tree-level and are only suppressed by the mixing between ordinary top and charm quarks, which is poorly constraint by current experimental values. The non-manifest case is also briefly discussed.

  17. Vacuum decay in a soluble model

    SciTech Connect

    Ferraz de Camargo F, A.; Shellard, R.C.; Marques, G.C.

    1984-03-15

    We study a field-theoretical model where the decay rate of the false vacuum can be computed up to the first quantum corrections in both the high-temperature and zero-temperature limits. We find that the dependence of the decay rate on the height and width of the potential barrier does not follow the same simple area rule as in the quantum-mechanical case. Furthermore, its behavior is strongly model dependent.

  18. Single-Majoron emission in. mu. decay

    SciTech Connect

    Santamaria, A.; Pich, A.; Bernabeu, J.

    1985-11-01

    The ..mu -->..etheta and ..mu -->..erho/sub L/ decays, where theta is a Nambu-Goldstone boson associated with the B-L breakdown and rho/sub L/ is a very light neutral Higgs boson, are evaluated in the framework of the triplet model of Gelmini and Roncadelli. It is shown that the widths of these decay modes may be comparable to the ..mu -->..e..gamma.. one.

  19. First forbidden beta decay in light nuclei

    SciTech Connect

    Millener, D.J.; Warburton, E.K.

    1984-01-01

    Beta decay matrix elements for the operators sigma dot del and sigma dot r are calculated for eight J/sup +/ ..-->.. J/sup -/ or J/sup -/ ..-->.. J/sup +/ beta transitions. Results using harmonic oscillator wave functions differ markedly from those using more realistic Woods-Saxon wave functions. A substantial contribution to the sigma dot del matrix elements from pion exchange currents is required to reproduce the experimental beta decay rates. 15 references.

  20. Exact relativistic {beta} decay endpoint spectrum

    SciTech Connect

    Masood, S. S.; Nasri, S.; Schechter, J.; Tortola, M. A.; Valle, J. W. F.

    2007-10-15

    The exact relativistic form for the {beta} decay endpoint spectrum is derived and presented in a simple factorized form. We show that our exact formula can be well approximated to yield the endpoint form used in the fit method of the KATRIN Collaboration. We also discuss the three-neutrino case and how information from neutrino oscillation experiments may be useful in analyzing future {beta} decay endpoint experiments.