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1

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

E-Print Network [OSTI]

of the decaying radioactive nuclide, and even the distance between Earth and the Sun at the time of the half-life measurement. In this study we present evidence that the initial beliefs in the immutability of radioactive half-life (with the exception of a few...

Goodwin, John 1953-

2013-01-16T23:59:59.000Z

2

Measurement of the double beta decay half-life of Nd-150 and search for neutrinoless decay modes with the NEMO-3 detector  

E-Print Network [OSTI]

The half-life for two-neutrino double beta decay of Nd-150 has been measured with data taken by the NEMO 3 experiment at the Modane Underground Laboratory. The limits are also set on the half-life of different neutrinoless double beta decay of this isotope.

Nasim Fatemi-Ghomi

2009-05-11T23:59:59.000Z

3

Average and recommended half-life values for two neutrino double beta decay  

E-Print Network [OSTI]

All existing positive results on two neutrino double beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{100}$Mo - $^{100}$Ru ($0^+_1$), $^{116}$Cd, $^{130}$Te, $^{136}$Xe, $^{150}$Nd, $^{150}$Nd - $^{150}$Sm ($0^+_1$) and $^{238}$U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of $^{128}$Te, and $^{130}$Ba are proposed. Given the measured half-life values, nuclear matrix elements were calculated using latest (more reliable and precise) values for phase space factor. Finally, previous results (PRC 81 (2010) 035501) were up-dated and results for $^{136}$Xe were added.

A. S. Barabash

2015-01-21T23:59:59.000Z

4

Measurement of the Double Beta Decay Half-life of 130Te with the NEMO-3 Detector  

E-Print Network [OSTI]

This Letter reports results from the NEMO-3 experiment based on an exposure of 1275 days with 661g of 130Te in the form of enriched and natural tellurium foils. With this data set the double beta decay rate of 130Te is found to be non-zero with a significance of 7.7 standard deviations and the half-life is measured to be T1/2 = (7.0 +/- 0.9(stat) +/- 1.1(syst)) x 10^{20} yr. This represents the most precise measurement of this half-life yet published and the first real-time observation of this decay.

Arnold, R; Baker, J; Barabash, A S; Basharina-Freshville, A; Blondel, S; Bongrand, M; Broudin-Bay, G; Brudanin, V; Caffrey, A J; Chapon, A; Chauveau, E; Durand, D; Egorov, V; Flack, R; Garrido, X; Grozier, J; Guillon, B; Hubert, Ph; Jackson, C M; Jullian, S; Kauer, M; Klimenko, A; Kochetov, O; Konovalov, S I; Kovalenko, V; Lalanne, D; Lamhamdi, T; Lang, K; Liptak, Z; Lutter, G; Mamedov, F; Marquet, Ch; Martin-Albo, J; Mauger, F; Mott, J; Nachab, A; Nemchenok, I; Nguyen, C H; Nova, F; Novella, P; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Reyss, J L; Richards, B; Ricol, J S; Saakyan, R; Sarazin, X; Shitov, Yu; Simard, L; Šimkovic, F; Smolnikov, A; Söldner-Rembold, S; Štekl, I; Suhonen, J; Sutton, C S; Szklarz, G; Thomas, J; Timkin, V; Torre, S; Tretyak, V I; Umatov, V; Vála, L; Vanyushin, I; Vasiliev, V; Vorobel, V; Vylov, T; Zukauskas, A

2011-01-01T23:59:59.000Z

5

Conversion of experimental half-life to effective electron neutrino mass in 0nubetabeta decay  

SciTech Connect (OSTI)

The Germanium Detector Array (GERDA) collaboration will be searching for neutrinoless double beta decay of {sup 76}Ge. As a result it will measure the half-life T{sub 1/2} of this rare process; or at least a new value for the lower limit for T{sub 1/2} will be derived. The sensitivity of the GERDA experiment on the effective electron neutrino mass depends on the theoretical value for the nuclear matrix element M and the kinematical phase space factor G.In this Brief Report we focus on existing difficulties in applying the dimensionless values of M calculated by various theoretical groups, which use different methods and parametrizations. The implicit radius dependencies in M and G are discussed. Resulting values of the neutrino mass are tabulated for various representative half-lives T{sub 1/2} representing the sensitivity of the various phases of the GERDA experiment.

Smolnikov, Anatoly; Grabmayr, Peter [Joint Institute for Nuclear Research, Dubna, Russia, and Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Kepler Center for Astro and Particle Physics, Eberhard Karls Universitaet Tuebingen (Germany)

2010-02-15T23:59:59.000Z

6

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

SciTech Connect (OSTI)

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

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

2012-01-23T23:59:59.000Z

7

Analysis of environmental influences in nuclear half-life measurements exhibiting time-dependent decay rates  

E-Print Network [OSTI]

In a recent series of papers evidence has been presented for correlations between solar activity and nuclear decay rates. This includes an apparent correlation between Earth-Sun distance and data taken at Brookhaven National Laboratory (BNL), and at the Physikalisch-Technische Bundesanstalt (PTB). Although these correlations could arise from a direct interaction between the decaying nuclei and some particles or fields emanating from the Sun, they could also represent an "environmental" effect arising from a seasonal variation of the sensitivities of the BNL and PTB detectors due to changes in temperature, relative humidity, background radiation, etc. In this paper, we present a detailed analysis of the responses of the detectors actually used in the BNL and PTB experiments, and show that sensitivities to seasonal variations in the respective detectors are likely too small to produce the observed fluctuations.

Jenkins, Jere H; Fischbach, Ephraim

2009-01-01T23:59:59.000Z

8

Analysis of environmental influences in nuclear half-life measurements exhibiting time-dependent decay rates  

E-Print Network [OSTI]

In a recent series of papers evidence has been presented for correlations between solar activity and nuclear decay rates. This includes an apparent correlation between Earth-Sun distance and data taken at Brookhaven National Laboratory (BNL), and at the Physikalisch-Technische Bundesanstalt (PTB). Although these correlations could arise from a direct interaction between the decaying nuclei and some particles or fields emanating from the Sun, they could also represent an "environmental" effect arising from a seasonal variation of the sensitivities of the BNL and PTB detectors due to changes in temperature, relative humidity, background radiation, etc. In this paper, we present a detailed analysis of the responses of the detectors actually used in the BNL and PTB experiments, and show that sensitivities to seasonal variations in the respective detectors are likely too small to produce the observed fluctuations.

Jere H. Jenkins; Daniel W. Mundy; Ephraim Fischbach

2009-12-29T23:59:59.000Z

9

Measurement of the double-{beta} decay half-life of {sup 150}Nd and search for neutrinoless decay modes with the NEMO-3 detector  

SciTech Connect (OSTI)

The half-life for double-{beta} decay of {sup 150}Nd has been measured by the NEMO-3 experiment at the Modane Underground Laboratory. Using 924.7 days of data recorded with 36.55 g of {sup 150}Nd, we measured the half-life for 2{nu}{beta}{beta} decay to be T{sub 1/2}{sup 2{nu}}=(9.11{sub -0.22}{sup +0.25}(stat.){+-}0.63(syst.))x10{sup 18} yr. The observed limit on the half-life for neutrinoless double-{beta} decay is found to be T{sub 1/2}{sup 0{nu}}>1.8x10{sup 22} yr at 90% confidence level. This translates into a limit on the effective Majorana neutrino mass of <4.0-6.3 eV if the nuclear deformation is taken into account. We also set limits on models involving Majoron emission, right-handed currents, and transitions to excited states.

Argyriades, J.; Augier, C.; Bongrand, M.; Jullian, S.; Lalanne, D.; Sarazin, X.; Simard, L.; Szklarz, G. [LAL, Universite Paris-Sud 11, CNRS/IN2P3, Orsay (France); Arnold, R. [IPHC, Universite de Strasbourg, CNRS/IN2P3, F-67037 Strasbourg (France); Baker, J.; Caffrey, A. J. [INL, Idaho Falls, Idaho 83415 (United States); Barabash, A. S.; Konovalov, S. I.; Umatov, V.; Vanyushin, I. [Institute of Theoretical and Experimental Physics, RU-117259 Moscow (Russian Federation); Basharina-Freshville, A.; Daraktchieva, Z.; Flack, R.; Kauer, M.; King, S. [University College London, WC1E 6BT London (United Kingdom)] (and others)

2009-09-15T23:59:59.000Z

10

Measurement of the two neutrino double beta decay half-life of Zr-96 and search for associated neutrinoless processes with the NEMO-3 detector  

E-Print Network [OSTI]

Using 1221 days of data from the NEMO-3 detector, the measurement of Zr-96 2vbb decay half-life is [2.35 +/- 0.14(stat) +/- 0.19(syst)] x 10^19 yr. Different characteristics of the final state electrons have been studied, such as the energy sum, individual electron energy, and angular distribution. The 2v nuclear matrix element is extracted using the measured 2vbb half-life and is 0.049 +/- 0.003. A 90% CL limit is set on the 0vbb decay half-life of > 9.2 x 10^21 yr corresponding to a limit on the effective Majorana neutrino mass < 7.2 - 19.5 eV. Limits on other mechanisms of 0vbb decay have also been set.

Argyriades, J; Augier, C; Baker, J; Barabash, A S; Bongrand, M; Broudin-Bay, G; Brudanin, V B; Caffrey, A J; Chapon, A; Chauveau, E; Daraktchieva, Z; Durand, D; Egorov, V G; Fatemi-Ghomi, N; Flack, R; Freshville, A; Guillon, B; Hubert, Ph; Jullian, S; Kauer, M; King, S; Kochetov, O I; Konovalov, S I; Kovalenko, V E; Lalanne, D; Lang, K; Lemiere, Y; Lutter, G; Mamedov, F; Marquet, Ch; Martín-Albo, J; Mauger, F; Nachab, A; Nasteva, I; Nemchenok, I B; Nova, F; Novella, P; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Reyss, J L; Ricol, J S; Saakyan, R; Sarazin, X; Simard, L; Shitov, Yu A; Smolnikov, A A; Snow, S; Söldner-Rembold, S; Stekl, I; Sutton, C S; Szklarz, G; Thomas, J; Timkin, V V; Tretyak, V I; Tretyak, Vl I; Umatov, V I; Vŕla, L; Vanyushin, I A; Vasiliev, V A; Vorobel, V; Vylov, Ts

2009-01-01T23:59:59.000Z

11

Average and recommended half-life values for two neutrino double beta decay: Upgrade-2013  

SciTech Connect (OSTI)

All existing positive results on two neutrino double beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of {sup 48}Ca, {sup 76}Ge, {sup 82}Se, {sup 96}Zr, {sup 100}Mo, {sup 100}Mo?{sup 100}Ru (0{sub 1}{sup +}), {sup 116}Cd, {sup 130}Te, {sup 136}Xe, {sup 150}Nd, {sup 150}Nd?{sup 150}Sm (0{sub 1}{sup +}) and {sup 238}U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of {sup 128}Te and {sup 130}Ba are proposed. I recommend the use of these results as the most currently reliable values for half-lives.

Barabash, A. S. [Institute of Theoretical and Experimental Physics, B. Cheremushkinskaya 25, 117218 Moscow (Russian Federation)

2013-12-30T23:59:59.000Z

12

Measurement of the half-life of the T=$\\frac{1}{2}$ mirror decay of $^{19}$Ne and its implication on physics beyond the standard model  

E-Print Network [OSTI]

The $\\frac{1}{2}^+ \\rightarrow \\frac{1}{2}^+$ superallowed mixed mirror decay of $^{19}$Ne to $^{19}$F is excellently suited for high precision studies of the weak interaction. However, there is some disagreement on the value of the half-life. In a new measurement we have determined this quantity to be $T_{1/2}$ = $17.2832 \\pm 0.0051_{(stat)}$ $\\pm 0.0066_{(sys)}$ s, which differs from the previous world average by 3 standard deviations. The impact of this measurement on limits for physics beyond the standard model such as the presence of tensor currents is discussed.

L. J. Broussard; H. O. Back; M. S. Boswell; A. S. Crowell; P. Dendooven; G. S. Giri; C. R. Howell; M. F. Kidd; K. Jungmann; W. L. Kruithof; A. Mol; C. J. G. Onderwater; R. W. Pattie Jr.; P. D. Shidling; M. Sohani; D. J. van der Hoek; A. Rogachevskiy; E. Traykov; O. O. Versolato; L. Willmann; H. W. Wilschut; A. R. Young

2014-05-28T23:59:59.000Z

13

Determination of the half-life of the ground state of {sup 229}Th by using {sup 232}U and {sup 233}U decay series  

SciTech Connect (OSTI)

The half-life of the ground state of {sup 229}Th ({sup 229}Th{sup g}) has become an important factor in nuclear technology, for example, in the geological disposal of nuclear spent fuel. However, the values reported in two previous studies are not in agreement. This study reevaluates the half-life of {sup 229}Th{sup g} by using a simple and reliable method. The {sup 232}U/{sup 233}U activity ratio of a {sup 232,233}U sample was measured by high-resolution {alpha}-particle spectrometry. Next, the {sup 228}Th/{sup 229}Th{sup g} activity ratio of the Th sample, which was grown from the {sup 232,233}U sample, was also measured. The half-life of {sup 229}Th{sup g} was calculated from these activity ratios, the growth time, and the half-lives of {sup 232}U, {sup 233}U, and {sup 228}Th. From the results of these five measurements, the half-life of {sup 229}Th{sup g} is determined to be 7932 {+-} 55 yr at a confidence level of 2{sigma}.

Kikunaga, H. [Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Suzuki, T.; Nomura, M. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550 (Japan); Mitsugashira, T. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Miyagi 980-8577 (Japan); Shinohara, A. [Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

2011-07-15T23:59:59.000Z

14

Half life for spontaneous fission of curium-245  

SciTech Connect (OSTI)

A sample of curium-245 of extremely high enrichment was obtained with an electromagnetic separator. The half-life for spontaneous fission was determined by measuring the rate of alpha decay. (AIP)

Druzhinin, A.A.; Polynov, V.N.; Vesnovskii, S.P.; Korochkin, A.M.; Lbov, A.A.; Nikitin, E.A.

1985-02-01T23:59:59.000Z

15

Half-Life of $^{14}$O  

E-Print Network [OSTI]

We have measured the half-life of $^{14}$O, a superallowed $(0^{+} \\to 0^{+})$ $\\beta$ decay isotope. The $^{14}$O was produced by the $^{12}$C($^{3}$He,n)$^{14}$O reaction using a carbon aerogel target. A low-energy ion beam of $^{14}$O was mass separated and implanted in a thin beryllium foil. The beta particles were counted with plastic scintillator detectors. We find $t_{1/2} = 70.696\\pm 0.052$ s. This result is $1.5\\sigma$ higher than an average value from six earlier experiments, but agrees more closely with the most recent previous measurement.

J. T. Burke; P. A. Vetter; S. J. Freedman; B. K. Fujikawa; W. T. Winter

2006-07-27T23:59:59.000Z

16

Determination of the half-life of /sup 243/ Cm  

SciTech Connect (OSTI)

The authors determine the half life of Cm 243 (T/sub alpha 243/) relative to the half-life of Cm 244 (whose value is known with high accuracy) from the molar ratios of the mixture of the nuclide studied with Cm 244 and the nuclides of plutonium, forming as a result of the alpha decay of curium nuclides. The results of the calculations of T/sub alpha 243/ based on the formula presented are shown. The random error for the average value of T/sub alpha 243/ is presented with a confidence probability of 0.95.

Timofeev, G.A.; Kalygin, V.V.; Privalova, P.A.

1986-10-01T23:59:59.000Z

17

The significance of using the Newcomb-Benford law as a test of nuclear half-life calculations  

E-Print Network [OSTI]

Half-life number sequences collected from nuclear data charts are found to obey the Newcomb-Benford law. Based on this fact, it has been suggested recently, that this law should be used to test the quality of nuclear decay models. In this paper we briefly recall how, when and why the Newcomb-Benford law can be observed in a set of numbers with a given probability distribution. We investigate the special case of nuclear half-lives, and show that the law provides no additional clue in understanding decay half-lives. Thus, it can play no significant role in testing nuclear decay theories.

Janos Farkas; Gyorgy Gyurky

2010-06-18T23:59:59.000Z

18

Half-life of {sup 151}Sm remeasured  

SciTech Connect (OSTI)

The half-life of {sup 151}Sm was redetermined and compared with literature values. A {sup 151}Sm{sub 2}O{sub 3} sample was produced by exposing {sup 150}Sm{sub 2}O{sub 3} to the high neutron flux of the heavy water research reactor at the China Institute of Atomic Energy (CIAE). The number of atoms and the activity of {sup 151}Sm in the sample were measured by thermal ionization mass spectrometry (TIMS) and liquid scintillation counting (LSC), respectively. The half-life of {sup 151}Sm determined in this work is 96.6 yr, with a standard uncertainty of 2.4 yr based on a quadratic summation of the uncertainty components from the measurements of the number of atoms and the activity of {sup 151}Sm.

He Ming; Shen Hongtao; Shi Guozhu; Yin Xinyi; Tian Weizhi; Jiang Shan [Department of Nuclear Physics, China Institute of Atomic Energy, Post Office Box 275-50, Beijing 102413 (China)

2009-12-15T23:59:59.000Z

19

The 198Au beta-half-life in the metal Au revisited  

E-Print Network [OSTI]

The half-life of the beta-decay of 198Au has been measured for room temperature and 12 K. The resulting values of T(RT) = 2.684 +- 0.004 d and T(12 K) = 2.687 +- 0.005 d agree well within statistical uncertainties. An evidence for a temperature dependence of the half-life was not observed.

K. Fortak; R. Kunz; L. Gialanella; H. -W. Becker; J. Meijer; F. Strieder

2010-09-10T23:59:59.000Z

20

Measurement of the double beta decay half-life of ^{100}Mo to the 0^{+}_{1} excited state, and ^{48}Ca to the ground state in the NEMO 3 experiment.  

E-Print Network [OSTI]

??NEMO 3 is a double beta decay experiment situated in the Fréjus tunnel which runs between France and Italy. If neutrinoless double beta decay is… (more)

King, S.L.

2009-01-01T23:59:59.000Z

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


21

Half-life and gamma abundance ratio measurements of Sm-153  

SciTech Connect (OSTI)

The measurement of the decay of 153Sm was observed by gamma spectrometry, liquid scintillation counting and gas proportional counting in an attempt to confirm the half life and gamma abundance ratios for this isotope. Recent changes in the published nuclear decay data indicate that historical literature values may be biased. The 153Sm was made by the neutron activation of ultrapure isotopically enriched 152Sm to create 153Sm. The decay measurements were made over a three week period and no other isotopes were detected during this time. The gamma abundance ratio for the 103 keV gamma was measured to be (27.9%) which is 4% lower than the published data. In addition, the half life was 1.9308 days, which is 0.34% lower than the published data.

Friese, Judah I.; Payne, Rosara F.; Greenwood, Lawrence R.; Soderquist, Chuck Z.; Garofoli, Stephanie J.

2009-11-02T23:59:59.000Z

22

Half-life for spontaneous fission of /sup 243/Cm  

SciTech Connect (OSTI)

A method is proposed for measuring the half-life for spontaneous fission of curium 243. Isotope separation and purification techniques are described and the isotope ratio of the purified target is given. The efficiency of fission fragment detection for solid state mica detectors was measured with a curium 244 standard. Results for the rate of spontaneous fission are tabulated.

Polynov, V.N.; Druzhinin, A.A.; Korochkin, A.M.; Nikitin, E.A.; Bochkarev, V.A.; Vyachin, V.N.; Lapin, V.G.; Maksimov, M.Yu.

1987-10-01T23:59:59.000Z

23

Precise measurement of the 222Rn half-life: a probe to monitor the stability of radioactivity  

E-Print Network [OSTI]

We give the results of a study on the 222Rn decay we performed in the Gran Sasso Laboratory (LNGS) by detecting the gamma rays from the radon progeny. The motivation was to monitor the stability of radioactivity measuring several times per year the half-life of a short lifetime (days) source instead of measuring over a long period the activity of a long lifetime (tens or hundreds of years) source. In particular, we give the reason of the large periodical fluctuations in the count rate of the gamma rays due to radon inside a closed canister which has been described in literature and which has been attributed to a possible influence of a component in the solar irradiation affecting the nuclear decay rates. We then provide the result of four half-life measurements we performed underground at LNGS in the period from May 2014 to January 2015 with radon diffused into olive oil. Briefly, we did not measure any change of the 222Rn half-life with a 8*10^-5 precision. Finally, we provide the most precise value for the 222Rn half-life: 3.82146(16){stat}(4){syst} days.

E. Bellotti; C. Broggini; G. Di Carlo; M. Laubenstein; R. Menegazzo

2015-01-30T23:59:59.000Z

24

Precise measurement of the 222Rn half-life: a probe to monitor the stability of radioactivity  

E-Print Network [OSTI]

We give the results of a study on the 222Rn decay we performed in the Gran Sasso Laboratory (LNGS) by detecting the gamma rays from the radon progeny. The motivation was to monitor the stability of radioactivity measuring several times per year the half-life of a short lifetime (days) source instead of measuring over a long period the activity of a long lifetime (tens or hundreds of years) source. In particular, we give the reason of the large periodical fluctuations in the count rate of the gamma rays due to radon inside a closed canister which has been described in literature and which has been attributed to a possible influence of a component in the solar irradiation affecting the nuclear decay rates. We then provide the result of four half-life measurements we performed underground at LNGS in the period from May 2014 to January 2015 with radon diffused into olive oil. Briefly, we did not measure any change of the 222Rn half-life with a 8*10^-5 precision. Finally, we provide the most precise value for the ...

Bellotti, E; Di Carlo, G; Laubenstein, M; Menegazzo, R

2015-01-01T23:59:59.000Z

25

EFFECTIVE HALF-LIFE OF CESIUM-137 IN VARIOUS ENVIRONMENTAL MEDIA AT THE SAVANNAH RIVER SITE  

SciTech Connect (OSTI)

During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities into the SRS environment. However, only a relatively small number of pathways, most importantly {sup 137}Cs in fish and deer, have contributed significantly to doses and risks to the public. The “effective” half-lives (T{sub e}) of {sup 137}Cs (which include both physical decay and environmental dispersion) in Savannah River floodplain soil and vegetation and in fish and white-tailed deer from the SRS were estimated using long-term monitoring data. For 1974–2011, the T{sub e}s of {sup 137}Cs in Savannah River floodplain soil and vegetation were 17.0 years (95% CI = 14.2–19.9) and 13.4 years (95% CI = 10.8–16.0), respectively. These T{sub e}s were greater than in a previous study that used data collected only through 2005 as a likely result of changes in the flood regime of the Savannah River. Field analyses of {sup 137}Cs concentrations in deer collected during yearly controlled hunts at the SRS indicated an overall T{sub e} of 15.9 years (95% CI = 12.3–19.6) for 1965–2011; however, the T{sub e} for 1990–2011 was significantly shorter (11.8 years, 95% CI = 4.8–18.8) due to an increase in the rate of {sup 137}Cs removal. The shortest T{sub e}s were for fish in SRS streams and the Savannah River (3.5–9.0 years), where dilution and dispersal resulted in rapid {sup 137}Cs removal. Long-term data show that T{sub e}s are significantly shorter than the physical half-life of {sup 137}Cs in the SRS environment but that they can change over time. Therefore, it is desirable have a long period of record for calculating Tes and risky to extrapolate T{sub e}s beyond this period unless the processes governing {sup 137}Cs removal are clearly understood.

Jannik, T.; Paller, M.; Baker, R.

2013-12-12T23:59:59.000Z

26

Near-optimum procedure for half-life measurement by high-resolution gamma-ray spectrometry  

SciTech Connect (OSTI)

A near-optimum procedure for using high-resolution /gamma/-ray spectrometry to measure the half-lives of appropriate /gamma/-ray- emitting-nuclides is presented. Among the important points of the procedure are the employment of the reference source method for implicit correction of pileup and deadtime losses; the use of full-energy peak-area ratios as the fundamental measured quantities; and continuous, high-rate data acquisition to obtain good results in a fraction of a half-life if desired. Equations are given for estimating the precision of the computed half-lives in terms of total measurement time, number of spectral acquisitions, and the precision of peak-area ratios. Results of /sup 169/Yb half-life measurements are given as an example of the procedure's application. 3 refs., 2 tabs.

Parker, J.L.

1989-01-01T23:59:59.000Z

27

Measurement of the {sup 44}Ti half-life and its significance for supernova.  

SciTech Connect (OSTI)

In 1998, we reported the three-laboratory measurement of the {sup 44}Ti half-life which was determined relative to the well known value (5.2714 {+-} 0.0005 yr) of the {sup 60}Co half-life. We have continued the measurement at Argonne and Jerusalem and inclusion of data points for additional two years does not change our published value of 59.0 {+-} 0.6 yr.

Ahmad, I.; Greene, J. P.; Kutschera, W.; Paul, M.

1999-08-28T23:59:59.000Z

28

Searches for neutrinoless double beta decay  

E-Print Network [OSTI]

Neutrinoless double beta decay is a lepton number violating process whose observation would also establish that neutrinos are their own anti-particles. There are many experimental efforts with a variety of techniques. Some (EXO, Kamland-Zen, GERDA phase I and CANDLES) started take data in 2011 and EXO has reported the first measurement of the half life for the double beta decay with two neutrinos of $^{136}$Xe. The sensitivities of the different proposals are reviewed.

B. Schwingenheuer

2012-01-24T23:59:59.000Z

29

Search for baryon number violation in top-quark decays  

E-Print Network [OSTI]

A search for baryon number violation (BNV) in top-quark decays is performed using pp collisions produced by the LHC at [sqrt s]=8 TeV. The top-quark decay considered in this search results in one light lepton (muon or ...

CMS Collaboration

30

Precise half-life measurement of the superallowed beta(+) emitter (26)Si  

E-Print Network [OSTI]

We measured the half-life of the superallowed 0(+) -> 0(+) beta(+) emitter (26)Si to be 2245.3(7) ms. We used pure sources of (26)Si and employed a high-efficiency gas counter, whichwas sensitive to positrons from both this nuclide and its daughter...

Iacob, V. E.; Hardy, John C.; Banu, A.; Chen, L.; Golovko, V. V.; Goodwin, J.; Horvat, V.; Nica, N.; Park, H. I.; Trache, L.; Tribble, Robert E.

2010-01-01T23:59:59.000Z

31

Precise half-life measurement of the superallowed beta(+) emitter (10)C  

E-Print Network [OSTI]

The half-life of (10)C has been measured to be 19.310(4) s, a result with 0.02% precision, which is a factor of three improvement over the best previous result. Since (10)C is the lightest superallowed 0(+)-> 0(+) beta(+) emitter, its ft value has...

Iacob, V. E.; Hardy, John C.; Golovko, V.; Goodwin, J.; Nica, N.; Park, H. I.; Trache, L.; Tribble, Robert E.

2008-01-01T23:59:59.000Z

32

, 227 240 . Half-life Radioactive decay Reaction with 2200 m/s neutrons  

E-Print Network [OSTI]

. 700-800 U2N3 UN2 . 1.2.5. 1.5 . , . UF4 UF6 UO2 HF . UO3 + 4HF Boils at 1 atm UF6 Black ~1427 8.95 UF4 Green 1036 1457 6.70 U4F17 Black 430 Disp. 6.94 U2F9 390 Disp. 7.06 UF5 White 348 Disp. 6.45 UF6 Colorless 64.05 56.54 5.06 UCl3 Olive green 837 1657 5.51 UCl4 Dark

Hong, Deog Ki

33

Towards a precision measurement of the half life of neutrinoless double beta decay of 136Xe.  

E-Print Network [OSTI]

??Recent neutrino oscillation experiments provide proof that neutrinos are massive par- ticles, but the absolute neutrino mass scale remains unknown. Observation of neu- trinoless double… (more)

Stanford University, Dept. of Physics

2011-01-01T23:59:59.000Z

34

Precise half-life measurements for the superallowed beta(+) emitters Ar-34 and Cl-34  

E-Print Network [OSTI]

PHYSICAL REVIEW C 74, 055502 (2006) Precise half-life measurements for the superallowed ?+ emitters 34Ar and 34Cl V. E. Iacob,* J. C. Hardy, J. F. Brinkley, C. A. Gagliardi, V. E. Mayes, N. Nica, M. Sanchez-Vega, G. Tabacaru, L. Trache, and R. E... 15, 17 (2002). [5] J. C. Hardy et al., Nucl. Phys. A223, 157 (1974). 055502-7 V. E. IACOB et al. PHYSICAL REVIEW C 74, 055502 (2006) [6] V. E. Iacob, E. Mayes, J. C. Hardy, R. G. Neilson, M. Sanchez- Vega, A. Azhari, C. A. Gagliardi, L. Trache...

Iacob, V. E.; Hardy, John C.; Brinkley, J. F.; Gagliardi, Carl A.; Mayes, V. E.; Nica, N.; Sanchez-Vega, M.; Tabacaru, G.; Trache, L.; Tribble, Robert E.

2006-01-01T23:59:59.000Z

35

Factorization of number into prime numbers viewed as decay of particle into elementary particles conserving energy  

E-Print Network [OSTI]

Number theory is considered, by proposing quantum mechanical models and string-like models at zero and finite temperatures, where the factorization of number into prime numbers is viewed as the decay of particle into elementary particles conserving energy. In these models, energy of a particle labeled by an integer $n$ is assumed or derived to being proportional to $\\ln n$. The one-loop vacuum amplitudes, the free energies and the partition functions at finite temperature of the string-like models are estimated and compared with the zeta functions. The $SL(2, {\\bf Z})$ modular symmetry, being manifest in the free energies is broken down to the additive symmetry of integers, ${\\bf Z}_{+}$, after interactions are turned on. In the dynamical model existing behind the zeta function, prepared are the fields labeled by prime numbers. On the other hand the fields in our models are labeled, not by prime numbers but by integers. Nevertheless, we can understand whether a number is prime or not prime by the decay rate, namely by the corresponding particle can decay or can not decay through interactions conserving energy. Among the models proposed, the supersymmetric string-like model has the merit of that the zero point energies are cancelled and the energy levels may be stable against radiative corrections.

Akio Sugamoto

2008-10-24T23:59:59.000Z

36

Ecological half-life of 137Cs in fish from a stream contaminated by nuclear reactor effluents  

SciTech Connect (OSTI)

Radiocesium ({sup 137}Cs) concentrations were determined during 1974, 1981 and 1998 for seven species of fish inhabiting a stream (Steel Creek) contaminated by effluents from a nuclear reactor to examine the decline of this radionuclide in a natural ecosystem. Median {sup 137}Cs concentrations were highest in Micropterus salmoides (largemouth bass) during each year of the investigation (1974 = 6.67 Bq g{sup -1} dry wt. of whole body; 1981 = 3.72 Bq g{sup -1}; 1998 = 0.35 Bq g{sup -1}), but no patterns of differences were observed among Aphredoderus sayanus (pirate perch), Esox americanus (redfin pickerel), Lepomis auritus (redbreast sunfish), L. gulosus (warmouth), L. punctatus (spotted sunfish), and Notropis cummingsae (dusky shiner). Results demonstrated a rapid decline in {sup 137}Cs within fish from Steel Creek during the 24-year period. For example, {sup 137}Cs concentrations in all fish species declined significantly among years, even after accounting for radioactive decay. The observed percent declines in {sup 137}Cs concentrations of individual species were 3-4 times greater between 1974 and 1981 compared to that expected by physical decay alone, and 2-3 times greater during 1981-1998. Ecological half-lives (EHLs) of {sup 137}Cs in fish ranged from 4.43 years in A. sayanus to 6.53 years in L. gulosus. The EHL for {sup 137}Cs in all fish species combined was 5.54 years. Current levels of {sup 137}Cs in fish from Steel Creek (1.16 Bq g{sup -1} dry wt. of whole body to below detection limits) indicate that the consumption of fish from this ecosystem poses little risk to humans and sensitive wildlife species. These results demonstrate the importance of incorporating the concept of ecological half-life into determinations concerning the length and severity of potential risks associated with radiocontaminants.

Peles, J. [Pennsylvania State University, McKeesport; BryanJr, A. [Savannah River Ecology Lab; Garten Jr, Charles T [ORNL; Ribble, D. [Trinity University; Smith, M. [Savannah River Ecology Lab

2000-12-01T23:59:59.000Z

37

Status and prospects of searches for neutrinoless double beta decay  

E-Print Network [OSTI]

The simultaneous beta decay of two neutrons in a nucleus without the emission of neutrinos (called neutrinoless double beta decay) is a lepton number violating process which is not allowed in the Standard Model of particle physics. More than a dozen experiments using different candidate isotopes and a variety of detection techniques are searching for this decay. Some (EXO-200, Kamland-Zen, GERDA) started to take data recently. EXO and Kamland-Zen have reported first limits of the half life $T_{1/2}^{0\

Bernhard Schwingenheuer

2012-10-28T23:59:59.000Z

38

Neutrinoless Double Beta Decay within QRPA with Proton-Neutron Pairing  

E-Print Network [OSTI]

We have investigated the role of proton-neutron pairing in the context of the Quasiparticle Random Phase approximation formalism. This way the neutrinoless double beta decay matrix elements of the experimentally interesting A= 48, 76, 82, 96, 100, 116, 128, 130 and 136 systems have been calculated. We have found that the inclusion of proton-neutron pairing influences the neutrinoless double beta decay rates significantly, in all cases allowing for larger values of the expectation value of light neutrino masses. Using the best presently available experimental limits on the half life-time of neutrinoless double beta decay we have extracted the limits on lepton number violating parameters.

G. Pantis; F. Simkovic; J. D. Vergados; Amand Faessler

1996-12-14T23:59:59.000Z

39

Half-life of the electron-capture decay of (97)Ru: Precision measurement shows no temperature dependence  

E-Print Network [OSTI]

.8382(14) d at 19K, are consistent with, but much more precise than, previous room-temperature measurements. In addition, we have also measured the half-lives of the beta(-)-emitters (103)Ru and (105)Rh at both temperatures, and found them also to be unchanged....

Goodwin, J. R.; Golovko, V. V.; Iacob, V. E.; Hardy, John C.

2009-01-01T23:59:59.000Z

40

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

E-Print Network [OSTI]

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

Gando, A.

2013-01-01T23:59:59.000Z

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


41

SIMPLIFIED PROCEDURE FOR CERTAIN USERS OF SEALED SOURCES, SHORT HALF-LIFE MATERIALS,  

E-Print Network [OSTI]

authority with a minimum of: (1) a certification that no residual radioactive contamination attributable, AND SMALL QUANTITIES A large number of users of radioactive materials may use a simplified procedure that qualify for simplified decommissioning procedures are those where radioactive materials have been used

42

Bounds on Compositeness from Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

Assuming the existence of a heavy Majorana neutral particle arising from a composite model scenario we discuss the constraints imposed by present experimental limits of half-life neutrinoless double beta decay $(0\

Orlando Panella; Yogendra N. Srivastava

1994-11-07T23:59:59.000Z

43

Half-life measurements of isomeric states populated in projectile fragmentation  

SciTech Connect (OSTI)

The half-lives of excited isomeric states observed in {sup 195}Au, {sup 201}Tl and {sup 215}Rn are reported for the first time. Delayed {gamma}-rays were correlated with nuclei produced in the projectile fragmentation of relativistic {sup 238}U ions, unambiguously identified in terms of their atomic number (Z) and mass-to-charge ratio (A/Q) after traversing an in-flight separator. The observation of a long-lived isomeric state in {sup 195}Au with t{sub 1/2} = 16{sub -4}{sup +8}{mu}s is presented. Two shorter-lived isomeric states were detected in {sup 201}Tl and {sup 215}Rn with t{sub 1/2} = 95{sub -21}{sup +39} and 57{sub -12}{sup +21} ns respectively. In total 24 isomeric states were identified in different nuclei from Pt to Rn (A {approx} 200) during the current study, the majority of which were previously reported. The wealth of spectroscopic data provides the opportunity to determine the isomeric ratios over a wide range of Z, A and angular momentum (I h) of the reaction products. In particular, high-spin states with I Greater-Than-Or-Equivalent-To 18 h provide a robust test of theoretical models of fragmentation.

Bowry, M.; Podolay, Zs. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom)

2012-10-20T23:59:59.000Z

44

Neutrinoless double beta decay constrained by the existence of large extra dimensions  

E-Print Network [OSTI]

We present the possible influence on the half-life of neutrinoless double beta decay coming from the existence of $n$ extra spatial dimensions. The half-life in question depends on the mass of the electron neutrino. We base our analysis on the Majorana neutrino mass mechanism in Arkani-Hamed--Dimopoulos--Dvali model.

Marek Gó?d?; W. A. Kami?ski

2012-01-05T23:59:59.000Z

45

Search for Lepton-Flavor and Lepton-Number Violation in the Decay tau to lhh'  

SciTech Connect (OSTI)

A search for lepton-flavor and lepton-number violation in the decay of the tau lepton into one charged lepton and two charged hadrons is performed using 221.4 fb{sup -1} of data collected at an e{sup +}e{sup -} center-of-mass energy of 10.58 GeV with the BABAR detector at the PEP-II storage ring. In all 14 decay modes considered, the observed data are compatible with background expectations, and upper limits are set in the range {Beta}({tau} {yields} {ell}hh') < (0.7-4.8) x 10{sup -7} at 90% confidence level.

Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San

2005-06-29T23:59:59.000Z

46

Calculation of neutrinoless double decay matrix elements in the Interacting Boson Model  

SciTech Connect (OSTI)

We show the formalism required to calculate in the Interacting Boson Model the nuclear matrix elements which are necessary in the evaluation of the neutrinoless double beta ({beta}{beta}(0v)) decay half-life.

Barea, J. [Instituto de Estructura de la Materia, Consejo Superior de Investigaciones Cientificas, Unidad Asociada al Departamento de Fisica Atomica, Molecular y Nuclear. Facultad de Fisica, Universidad de Sevilla, Apartado 1065, 41080 Sevilla (Spain)

2009-11-09T23:59:59.000Z

47

Beta decay rates for r-process for nuclei near neutron number N=82  

E-Print Network [OSTI]

For r-process nucleosynthesis the beta decay rates of very neutron-rich nuclei are important ingredients. We consider the region around the neutron number N=82 and calculate the half-lives and rates for a number of nuclei. Forms for beta strength functions based on spectral distribution methods are used. The calculated half-lives are first compared to the observed values and then predictions are made for very neutron-rich nuclei close to drip line for which no experimental values are available.

Kamales Kar; Soumya Chakravarti

2008-12-01T23:59:59.000Z

48

PHYSICAL REVIEW C VOLUME 27, NUMBER 4 APRIL 1983 Atomic final-state interactions in tritium decay  

E-Print Network [OSTI]

PHYSICAL REVIEW C VOLUME 27, NUMBER 4 APRIL 1983 Atomic final-state interactions in tritium decay R of the ejected P ray with the bound atomic e1ectron in the P decay of a tritium atom. The excited state probabi1 effects are expected to be more pro- nounced, but not, to our knowledge, for tritium. The interaction

Williams, Roy

49

Scaling Factor Inconsistencies in Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

The modern theory of neutrinoless double beta decay includes a scaling factor that has often been treated inconsistently in the literature. The nuclear contribution to the decay half life can be suppressed by 15-20% when scaling factors are mismatched. Correspondingly, $$ is overestimated.

S. Cowell

2005-12-05T23:59:59.000Z

50

Scaling factor inconsistencies in neutrinoless double beta decay  

SciTech Connect (OSTI)

The modern theory of neutrinoless double beta decay includes a scaling factor that has often been treated inconsistently in the literature. The nuclear contribution to the decay half-life can be suppressed by 15%-20% when scaling factors are mismatched. Correspondingly, is overestimated.

Cowell, S. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2006-02-15T23:59:59.000Z

51

Search for the neutrinoless double beta decay of 100Mo with the NEMO3 detector and calorimeter research and development for the SuperNEMO experiment.  

E-Print Network [OSTI]

??The world’s most precise half-life measurement of T2nu1/2 = [7.02 ± 0.01(stat) ± 0.46(syst)] × 1018 years has been made for the 2??? decay of… (more)

Basharina-Freshville, A.

2012-01-01T23:59:59.000Z

52

Neutrinoless Double Beta Decay of Ge76, Se82, Mo100 and Xe136 to excited 0^+ states  

E-Print Network [OSTI]

The neutrinoless double beta decay transition to the first excited 0^+ collective final state is examined for A=76, 82, 100 and 136 nuclei by assuming light and heavy Majorana neutrino exchange mechanisms as well as the trilinear R-parity violating contributions. Realistic calculations of nuclear matrix elements have been performed within the renormalized quasiparticle random phase approximation. Transitions to the first excited two-quadrupole phonon 0^+ state are described within a boson expansion formalism and alternatively by using the operator recoupling method. We present the sensitivity parameters to different lepton number violating signals, which can be used in planning the neutrinoless double beta decay experiments. The half-life of neutrinoless double beta decay to the first excited state 0^+_1 is by a factor of 10 to 100 larger than that of the transition to the ground state.

F. Simkovic; M. Nowak; W. A. Kaminski; A. A. Raduta; Amand Faessler

2001-07-06T23:59:59.000Z

53

Double beta decay: present status  

E-Print Network [OSTI]

The present status of double beta decay experiments (including the search for $2\\beta^{+}$, EC$\\beta^{+}$ and ECEC processes) are reviewed. The results of the most sensitive experiments are discussed. Average and recommended half-life values for two-neutrino double beta decay are presented. Conservative upper limits on effective Majorana neutrino mass and the coupling constant of the Majoron to the neutrino are established as $ beta decay experiments with a sensitivity for the $$ at the level of (0.01-0.1) eV are considered.

A. S. Barabash

2008-07-18T23:59:59.000Z

54

nature biotechnology volume 27 number 12 december 2009 1 half-life for indications when an extended residence time in the cir-  

E-Print Network [OSTI]

and can complicate tight control over plasma Focus on synthetic biology This issue of Nature Biotechnology

Cai, Long

55

Neutrinoless double beta decay search with the NEMO 3 experiment  

E-Print Network [OSTI]

The NEMO 3 experiment searches for neutrinoless double beta decay and makes precision measurements of two-neutrino double beta decay in seven isotopes. The latest two-neutrino half-life results are presented, together with the limits on neutrinoless half-lives and the corresponding effective Majorana neutrino masses. Also given are the limits obtained on neutrinoless double beta decay mediated by Rp-violating SUSY, right-hand currents and different Majoron emission modes.

Irina Nasteva; for the NEMO 3 Collaboration

2008-10-03T23:59:59.000Z

56

Neutrinoless double beta decay search with the NEMO 3 experiment  

SciTech Connect (OSTI)

The NEMO 3 experiment searches for neutrinoless double beta decay and makes precision measurements of two-neutrino double beta decay in seven isotopes. The latest two-neutrino half-life results are presented, together with the limits on neutrinoless half-lives and the corresponding effective Majorana neutrino masses. Also given are the limits obtained on neutrinoless double beta decay mediated by R{sub p}-violating SUSY, right-hand currents and different Majoron emission modes.

Nasteva, Irina [Particle Physics Group, School of Physics and Astronomy, University of Manchester, Manchester, M13 9PL (United Kingdom)

2008-11-23T23:59:59.000Z

57

The beta-decay of 22Al  

E-Print Network [OSTI]

In an experiment performed at the LISE3 facility of GANIL, we studied the decay of 22Al produced by the fragmentation of a 36Ar primary beam. A beta-decay half-life of 91.1 +- 0.5 ms was measured. The beta-delayed one- and two-proton emission as well as beta-alpha and beta-delayed gamma decays were measured and allowed us to establish a partial decay scheme for this nucleus. New levels were determined in the daughter nucleus 22Mg. The comparison with model calculations strongly favours a spin-parity of 4+ for the ground state of 22Al.

N. L. Achouri; F. de Oliveira Santos; M. Lewitowicz; B. Blank; J. Aysto; G. Canchel; S. Czajkowski; P. Dendooven; A. Emsallem; J. Giovinazzo; N. Guillet; A. Jokinen; A. M. Laird; C. Longour; K. Perajarvi; N. Smirnova; M. Stanoiu; J. C. Thomas

2006-08-01T23:59:59.000Z

58

Neutrinoless double beta decay mediated by the neutrino magnetic moment  

E-Print Network [OSTI]

We present a new channel of the neutrinoless double beta decay. In this scenario neutrinos not only oscillate inside the nucleus but also interact with an external non-uniform magnetic field. We assume that the field rotates about the direction of motion of the neutrino and show, that for a certain speed of rotation the half-life of the $0\

Marek Gó?d?; Wies?aw A. Kami?ski

2014-11-07T23:59:59.000Z

59

New Advances in Neutrinoless Double Beta Decay Matrix Elements  

SciTech Connect (OSTI)

We present the matrix elements necessary to evaluate the half-life of some neutrinoless double beta decay candidates in the framework of the microscopic interacting boson model (IBM). We compare our results with those from other models and extract some simple features of the calculations.

Munoz, Jose Barea [Instituto de Estructura de la Materia, C.S.I.C. Unidad Asociada al Departamento de Fisica Atomica, Molecular y Nuclear, Facultad de Fisica, Universidad de Sevilla, Apartado 1065, 41080 Sevilla (Spain)

2010-08-04T23:59:59.000Z

60

Neutrinoless double beta decay mediated by the neutrino magnetic moment  

E-Print Network [OSTI]

We present a new channel of the neutrinoless double beta decay. In this scenario neutrinos not only oscillate inside the nucleus but also interact with an external non-uniform magnetic field. We assume that the field rotates about the direction of motion of the neutrino and show, that for a certain speed of rotation the half-life of the $0\

Gó?d?, Marek

2014-01-01T23:59:59.000Z

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


61

Sterile Neutrinos in Neutrinoless Double Beta Decay: An Update  

E-Print Network [OSTI]

We revisit the mechanism of neutrinoless double beta (NLDBD) decay mediated by the exchange with the heavy Majorana neutrino N of arbitrary mass mN, slightly mixed with the electron neutrino. By assuming the dominance of this mechanism we update the well known NLDBD-decay exclusion plot in the mass-mixing angle plane taking into account recent progress in calculation of nuclear matrix elements within quasiparticle random phase approximation and improved experimental bounds on the NLDBD-decay half-life of Ge-76 and Xe-136. We also consider the known formula approximating the mN dependence of the NLDBD-decay nuclear matrix element in a simple explicit form. We analyze its accuracy and specify the corresponding parameters allowing one to easily calculate the NLDBD-decay half-life for arbitrary mN for all the experimentally interesting isotopes without resorting to real nuclear structure calculations.

Faessler, Amand; Kovalenko, Sergey; Simkovic, Fedor

2014-01-01T23:59:59.000Z

62

Arbitrary mass Majorana neutrinos in neutrinoless double beta decay  

E-Print Network [OSTI]

We revisit the mechanism of neutrinoless double beta (NLDBD) decay mediated by the exchange with the heavy Majorana neutrino N of arbitrary mass mN, slightly mixed with the electron neutrino. By assuming the dominance of this mechanism, we update the well-known NLDBD-decay exclusion plot in the mass-mixing angle plane taking into account recent progress in the calculation of nuclear matrix elements within quasiparticle random phase approximation and improved experimental bounds on the NLDBD-decay half-life of Ge-76 and Xe-136. We also consider the known formula approximating the mN dependence of the NLDBD-decay nuclear matrix element in a simple explicit form. We analyze its accuracy and specify the corresponding parameters, allowing one to easily calculate the NLDBD-decay half-life for arbitrary mN for all the experimentally interesting isotopes without resorting to real nuclear structure calculations.

Amand Faessler; Marcela Gonzalez; Sergey Kovalenko; Fedor Simkovic

2014-08-26T23:59:59.000Z

63

LIMITS ON THE NUMBER OF GALACTIC YOUNG SUPERNOVA REMNANTS EMITTING IN THE DECAY LINES OF {sup 44}Ti  

SciTech Connect (OSTI)

We revise the assumptions of the parameters involved in predicting the number of supernova remnants detectable in the nuclear lines of the decay chain of {sup 44}Ti. Specifically, we consider the distribution of the supernova progenitors, the supernova rate in the Galaxy, the ratios of supernova types, the Galactic production of {sup 44}Ti, and the {sup 44}Ti yield from supernovae of different types to derive credible bounds on the expected number of detectable remnants. We find that, within 1? uncertainty, the Galaxy should contain an average of 5.1{sup +2.4}{sub -2.0} remnants detectable to a survey with a {sup 44}Ti decay line flux limit of 10{sup –5} photons cm{sup –2} s{sup –1}, with a probability of detecting a single remnant of 2.7{sup +10.0}{sub -2.4}%, and an expected number of detections between two and nine remnants, making the single detection of Cas A unlikely but consistent with our models. Our results show that the probability of detecting the brightest {sup 44}Ti flux source at the high absolute Galactic longitude of Cas A or above is ?10%. Using the detected flux of Cas A, we attempt to constrain the Galactic supernova rate and Galactic production of {sup 44}Ti, but find the detection to be only weakly informative. We conclude that even future surveys having 200 times more sensitivity than state-of-the-art surveys can be guaranteed to detect only a few new remnants, with an expected number of detections between 8 and 21 at a limiting {sup 44}Ti decay flux of 10{sup –7} photons cm{sup –2} s{sup –1}.

Dufour, François; Kaspi, Victoria M., E-mail: dufourf@physics.mcgill.ca [Department of Physics, McGill University, 3600 rue University, Montréal, QC H3A 2T8 (Canada)

2013-09-20T23:59:59.000Z

64

Alpha decay chains from element 113  

E-Print Network [OSTI]

Theoretical estimates of $\\alpha$-decay half lives of several nuclei in the decay from element 113 are presented. Calculations in a WKB framework using DDM3Y interaction and experimental Q-values are in good agreement with the experimental data. Half life calculations are found to be quite sensitive to the Q-values and angular momenta transfers. Calculated decay lifetime decreases, owing to more penetrability as well as thinner barrier, as Q-value increases. Deviations to this predominant behaviour observed in some recent experimental data may be attributed to non zero spin-parities in some cases.

P. Roy Chowdhury; D. N. Basu; C. Samanta

2007-04-30T23:59:59.000Z

65

The New Element Californium (Atomic Number 98)  

DOE R&D Accomplishments [OSTI]

Definite identification has been made of an isotope of the element with atomic number 98 through the irradiation of Cm{sup 242} with about 35-Mev helium ions in the Berkeley Crocker Laboratory 60-inch cyclotron. The isotope which has been identified has an observed half-life of about 45 minutes and is thought to have the mass number 244. The observed mode of decay of 98{sup 244} is through the emission of alpha-particles, with energy of about 7.1 Mev, which agrees with predictions. Other considerations involving the systematics of radioactivity in this region indicate that it should also be unstable toward decay by electron capture. The chemical separation and identification of the new element was accomplished through the use of ion exchange adsorption methods employing the resin Dowex-50. The element 98 isotope appears in the eka-dysprosium position on elution curves containing berkelium and curium as reference points--that is, it precedes berkelium and curium off the column in like manner that dysprosium precedes terbium and gadolinium. The experiments so far have revealed only the tripositive oxidation state of eka-dysprosium character and suggest either that higher oxidation states are not stable in aqueous solutions or that the rates of oxidation are slow. The successful identification of so small an amount of an isotope of element 98 was possible only through having made accurate predictions of the chemical and radioactive properties.

Seaborg, G. T.; Thompson, S. G.; Street, K. Jr.; Ghiroso, A.

1950-06-19T23:59:59.000Z

66

Nuclear Double Beta Decay, Fundamental Particle Physics, Hot Dark Matter, And Dark Energy  

E-Print Network [OSTI]

Nuclear double beta decay, an extremely rare radioactive decay process, is - in one of its variants - one of the most exciting means of research into particle physics beyond the standard model. The large progress in sensitivity of experiments searching for neutrinoless double beta decay in the last two decades - based largely on the use of large amounts of enriched source material in "active source experiments" - has lead to the observation of the occurrence of this process in nature (on a 6.4 sigma level), with the largest half-life ever observed for a nuclear decay process (2.2 x 10^{25} y). This has fundamental consequences for particle physics - violation of lepton number, Majorana nature of the neutrino. These results are independent of any information on nuclear matrix elements (NME)*. It further leads to sharp restrictions for SUSY theories, sneutrino mass, right-handed W-boson mass, superheavy neutrino masses, compositeness, leptoquarks, violation of Lorentz invariance and equivalence principle in the neutrino sector. The masses of light-neutrinos are found to be degenerate, and to be at least 0.22 +- 0.02 eV. This fixes the contribution of neutrinos as hot dark matter to >=4.7% of the total observed dark matter. The neutrino mass determined might solve also the dark energy puzzle. *(It is briefly discussed how important NME for 0nubb decay really are.)

Hans V. Klapdor-Kleingrothaus; Irina V. Krivosheina

2010-07-15T23:59:59.000Z

67

Probing New Physics Models of Neutrinoless Double Beta Decay with SuperNEMO  

E-Print Network [OSTI]

The possibility to probe new physics scenarios of light Majorana neutrino exchange and right-handed currents at the planned next generation neutrinoless double beta decay experiment SuperNEMO is discussed. Its ability to study different isotopes and track the outgoing electrons provides the means to discriminate different underlying mechanisms for the neutrinoless double beta decay by measuring the decay half-life and the electron angular and energy distributions.

Arnold, R; Baker, J; Barabash, A S; Basharina-Freshville, A; Bongrand, M; Brudanin, V; Caffrey, A J; Cebrián, S; Chapon, A; Chauveau, E; Dafni, Th; Deppisch, F F; Diaz, J; Durand, D; Egorov, V; Evans, J J; Flack, R; Fushima, K-I; Irastorza, I García; Garrido, X; Gómez, H; Guillon, B; Holin, A; Holy, K; Horkey, J J; Hubert, Ph; Hugon, C; Iguaz, F J; Ishihara, N; Jackson, C M; Jullian, S; Kauer, M; Kochetov, O; Konovalov, S I; Kovalenko, V; Lamhamdi, T; Lang, K; Lutter, G; Luzón, G; Mamedov, F; Marquet, Ch; Mauger, F; Monrabal, F; Nachab, A; Nasteva, I; Nemchenok, I; Nguyen, C H; Nomachi, M; Nova, F; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Povinec, P P; Richards, B; Ricol, J S; Riddle, C L; Rodríguez, A; Saakyan, R; Sarazin, X; Sedgbeer, J K; Serra, L; Shitov, Yu; Simard, L; Šimkovic, F; Söldner-Rembold, S; Štekl, I; Sutton, C S; Tamagawa, Y; Thomas, J; Timkin, V; Tretyak, V; Tretyak, Vl I; Umatov, V I; Vanyushin, I A; Vasiliev, R; Vasiliev, V; Vorobel, V; Waters, D; Yahlali, N; Žukauskas, A

2010-01-01T23:59:59.000Z

68

Probing New Physics Models of Neutrinoless Double Beta Decay with SuperNEMO  

E-Print Network [OSTI]

The possibility to probe new physics scenarios of light Majorana neutrino exchange and right-handed currents at the planned next generation neutrinoless double beta decay experiment SuperNEMO is discussed. Its ability to study different isotopes and track the outgoing electrons provides the means to discriminate different underlying mechanisms for the neutrinoless double beta decay by measuring the decay half-life and the electron angular and energy distributions.

R. Arnold; C. Augier; J. Baker; A. S. Barabash; A. Basharina-Freshville; M. Bongrand; V. Brudanin; A. J. Caffrey; S. Cebrián; A. Chapon; E. Chauveau; Th. Dafni; F. F. Deppisch; J. Diaz; D. Durand; V. Egorov; J. J. Evans; R. Flack; K-I. Fushima; I. García Irastorza; X. Garrido; H. Gómez; B. Guillon; A. Holin; K. Holy; J. J. Horkley; Ph. Hubert; C. Hugon; F. J. Iguaz; N. Ishihara; C. M. Jackson; S. Jullian; M. Kauer; O. Kochetov; S. I. Konovalov; V. Kovalenko; T. Lamhamdi; K. Lang; G. Lutter; G. Luzón; F. Mamedov; Ch. Marquet; F. Mauger; F. Monrabal; A. Nachab; I. Nasteva; I. Nemchenok; C. H. Nguyen; M. Nomachi; F. Nova; H. Ohsumi; R. B. Pahlka; F. Perrot; F. Piquemal; P. P. Povinec; B. Richards; J. S. Ricol; C. L. Riddle; A. Rodríguez; R. Saakyan; X. Sarazin; J. K. Sedgbeer; L. Serra; Yu. Shitov; L. Simard; F. Šimkovic; S. Söldner-Rembold; I. Štekl; C. S. Sutton; Y. Tamagawa; J. Thomas; V. Timkin; V. Tretyak; Vl. I. Tretyak; V. I. Umatov; I. A. Vanyushin; R. Vasiliev; V. Vasiliev; V. Vorobel; D. Waters; N. Yahlali; A. Žukauskas

2010-11-23T23:59:59.000Z

69

Double beta decay versus cosmology: Majorana CP phases and nuclear matrix elements  

SciTech Connect (OSTI)

We discuss the relation between the absolute neutrino mass scale, the effective mass measured in neutrinoless double beta decay, and the Majorana CP phases. Emphasis is placed on estimating the upper bound on the nuclear matrix element entering calculations of the double beta decay half-life. Combining the claimed evidence for neutrinoless double beta decay with the neutrino mass bound from cosmology, one of the Majorana CP phases can be constrained.

Deppisch, Frank; Paes, Heinrich [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, D-97074 Wuerzburg (Germany); Suhonen, Jouni [Department of Physics, University of Jyvaeskylae, P.O.B. 35, FIN-40014, Jyvaeskylae (Finland)

2005-08-01T23:59:59.000Z

70

Results on neutrinoless double beta decay of 76 Ge from Gerda Phase I  

E-Print Network [OSTI]

Results on neutrinoless double beta decay of 76 Ge from Gerda Phase I M. Agostini,14 M. Allardt,3 E and a lower limit is derived for the half-life of neutrinoless double beta decay of 76 Ge, T0 1/2> 2.1 · 1025 double beta decay of the isotope 76 Ge. Data con- sidered in the present analysis have been collected

71

Search for Neutrinoless Double-Beta Decay in 136 Xe with EXO-200  

E-Print Network [OSTI]

Search for Neutrinoless Double-Beta Decay in 136 Xe with EXO-200 M. Auger,1 D. J. Auty,2 P. S on a search for neutrinoless double-beta decay of 136Xe with EXO-200. No signal is observed for an exposure a lower limit on the half-life of the neutrinoless double-beta decay T0#12;#12; 1=2 Ă°136XeĂ? > 1:6 Ă? 1025

Piepke, Andreas G.

72

The decay of a new nuclide /sup 71/Br  

E-Print Network [OSTI]

The decay of mass-separated samples of the previously unknown nuclide /sup 71/Br have been investigated by means of the Chalk River on-line isotope separator. Eleven gamma -transitions were assigned to the decay of this nuclide and its half-life was measured to be 21.4+or-0.6 s. A simple decay scheme for /sup 71/Br has been constructed incorporating six levels in its daughter, /sup 71/Se. The half-life of the first excited state in /sup 71/Se was measured to be 5.5+or-1.0 mu s and the transition from this state to the ground state was found to be highly converted. Systematic trends in the level schemes of /sup 67 /Zn, /sup 69/Ge and /sup 71/Se are investigated. (16 refs).

Hagberg, E; Evans, H C; Hardy, J C; Koslowsky, V T; Schmeing, H; Schrewe, U J; Sharma, K S

1981-01-01T23:59:59.000Z

73

Superallowed 0(+)-> 0(+) nuclear beta decays: A critical survey with tests of the conserved vector current hypothesis and the standard model  

E-Print Network [OSTI]

A complete and critical survey is presented of all half-life, decay-energy, and branching-ratio measurements related to 20 superallowed 0(+)-> 0(+) decays...no measurements are ignored, although some are rejected for cause and others updated. A new calculation of the statistical rate function f is described and experimental ft values determined. The associated theoretical corrections needed to convert...

Hardy, John C.; Towner, IS.

2005-01-01T23:59:59.000Z

74

Limit on Neutrinoless ?? Decay of Xe-136 from the First Phase of KamLAND-Zen and Comparison with the Positive Claim in Ge-76  

E-Print Network [OSTI]

We present results from the first phase of the KamLAND-Zen double-beta decay experiment, corresponding to an exposure of 89.5 kg yr of Xe-136. We obtain a lower limit for the neutrinoless double-beta decay half-life of T_{1/2}^{0{\

KamLAND-Zen Collaboration

2013-02-19T23:59:59.000Z

75

Nuclear structure aspects of neutrinoless {beta}{beta} decay: limits on the electron neutrino mass  

SciTech Connect (OSTI)

We discuss some features of the nuclear structure elements participant in the calculation of the mass sector of the half-life of the neutrinoless double beta decay, and the consequences upon the adopted limits of the electron-neutrino mass.

Civitarese, O. [Department of Physics. University of La Plata, 1900 La Plata (Argentina); Suhonen, J. [Department of Physics. University of Jyvaeskyla, (Finland)

2007-02-12T23:59:59.000Z

76

Status of double beta decay experiments using isotopes other than Xe-136  

E-Print Network [OSTI]

Neutrinoless double beta decay is a lepton-number violating process predicted by many extensions of the standard model. It is actively searched for in several candidate isotopes within many experimental projects. The status of the experimental initiatives which are looking for the neutrinoless double beta decay in isotopes other than Xe-136 is reviewed, with special emphasis given to the projects that passed the R&D phase. The results recently released by the experiment GERDA are also summarized and discussed. The GERDA data give no positive indication of neutrinoless double beta decay of Ge-76 and disfavor in a model-independent way the long-standing observation claim on the same isotope. The lower limit reported by GERDA for the half-life of neutrinoless double beta decay of Ge-76 is T1/2 > 2.1e25 yr (90% C.L.), or T1/2 > 3.0e25 yr, when combined with the results of other Ge-76 predecessor experiments.

Luciano Pandola

2014-03-13T23:59:59.000Z

77

Status of double beta decay experiments using isotopes other than Xe-136  

E-Print Network [OSTI]

Neutrinoless double beta decay is a lepton-number violating process predicted by many extensions of the standard model. It is actively searched for in several candidate isotopes within many experimental projects. The status of the experimental initiatives which are looking for the neutrinoless double beta decay in isotopes other than Xe-136 is reviewed, with special emphasis given to the projects that passed the R&D phase. The results recently released by the experiment GERDA are also summarized and discussed. The GERDA data give no positive indication of neutrinoless double beta decay of Ge-76 and disfavor in a model-independent way the long-standing observation claim on the same isotope. The lower limit reported by GERDA for the half-life of neutrinoless double beta decay of Ge-76 is T1/2 > 2.1e25 yr (90% C.L.), or T1/2 > 3.0e25 yr, when combined with the results of other Ge-76 predecessor experiments.

Pandola, Luciano

2014-01-01T23:59:59.000Z

78

Neutrinoless Double Beta Decay in Heavy Deformed Nuclei  

E-Print Network [OSTI]

The zero neutrino mode of the double beta decay in heavy deformed nuclei is investigated in the framework of the pseudo SU(3) model, which has provided an accurate description of collective nuclear structure and predicted half-lives for the two neutrino mode in good agreement with experiments. In the case of $^{238}U$ the calculated zero neutrino half-life is at least three orders of magnitude greater than the two neutrino one, giving strong support of the identification of the radiochemically determined half-life as being the two neutrino double beta decay. For $^{150}Nd$ the zero neutrino matrix elements are of the order of magnitude of, but lesser than, those evaluated using the QRPA. This result confirms that different nuclear models produce similar zero neutrino matrix elements, contrary to the two neutrino case. Using these pseudo SU(3) results and the upper limit for the neutrino mass we estimate the $\\beta\\beta_{0\

Jorge G. Hirsch; O. Castańos; P. O. Hess

1994-07-12T23:59:59.000Z

79

Improved bounds on SUSY accompanied neutrinoless double beta decay  

E-Print Network [OSTI]

Neutrinoless double beta decay induced by light Majorana neutrino exchange between two decaying nucleons with squark/slepton exchange inside one and W exchange inside the other nucleon (so-called vector-scalar exchange) gives stringent limits on R-parity violating interactions. We have extended previous work by including the tensor contribution to the transition rate. We discuss the improved limits on trilinear \\Rp -MSSM couplings imposed by the current experimental limit on the $\\znbb$ decay half-life of $^{76}$Ge.

H. Päs; M. Hirsch; H. V. Klapdor-Kleingrothaus

1999-07-14T23:59:59.000Z

80

Search for Neutrinoless Double-Beta Decay in $^{136}$Xe with EXO-200  

E-Print Network [OSTI]

We report on a search for neutrinoless double-beta decay of $^{136}$Xe with EXO-200. No signal is observed for an exposure of 32.5 kg-yr, with a background of ~1.5 x 10^{-3} /(kg yr keV) in the $\\pm 1\\sigma$ region of interest. This sets a lower limit on the half-life of the neutrinoless double-beta decay $T_{1/2}^{0\

M. Auger; D. J. Auty; P. S. Barbeau; E. Beauchamp; V. Belov; C. Benitez-Medina; M. Breidenbach; T. Brunner; A. Burenkov; B. Cleveland; S. Cook; T. Daniels; M. Danilov; C. G. Davis; S. Delaquis; R. deVoe; A. Dobi; M. J. Dolinski; A. Dolgolenko; M. Dunford; W. Fairbank Jr.; J. Farine; W. Feldmeier; P. Fierlinger; D. Franco; G. Giroux; R. Gornea; K. Graham; G. Gratta; C. Hall; K. Hall; C. Hargrove; S. Herrin; M. Hughes; A. Johnson; T. N. Johnson; A. Karelin; L. J. Kaufman; A. Kuchenkov; K. S. Kumar; D. S. Leonard; F. Leonard; D. Mackay; R. MacLellan; M. Marino; B. Mong; M. Montero Diez; A. R. Muller; R. Neilson; R. Nelson; A. Odian; I. Ostrovskiy; K. O'Sullivan; C. Ouellet; A. Piepke; A. Pocar; C. Y. Prescott; K. Pushkin; P. C. Rowson; J. J. Russell; A. Sabourov; D. Sinclair; S. Slutsky; V. Stekhanov; T. Tolba; D. Tosi; K. Twelker; P. Vogel; J. -L. Vuilleumier; A. Waite; T. Walton; M. Weber; U. Wichoski; J. Wodin; J. D. Wright; L. Yang; Y. -R. Yen; O. Ya. Zeldovich

2012-07-20T23:59:59.000Z

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


81

A search for various double beta decay modes of tin isotopes  

E-Print Network [OSTI]

For the first time an extensive search for various double beta decay modes of 124Sn and 112Sn has been performed. A total exposure of 43.29 kg.days has been accumulated. New half-life limits of 124Sn into excited states of 124Te have been obtained; the lower half-life limit for the first excited 2+ state at 602.7keV is T_1/2 > 3.1 *10^{18}yrs (90 % CL) and for the first excited 0+ state T_1/2 > 7.7 *10^{18}yrs (90 % CL). For the very first time, ground state and excited state transitions of 112Sn have been experimentally explored. The obtained half-life limits for ECEC and beta+/EC into the first excited 2+ state of 112Cd are both T_1/2 >1.4 *10^{18}yrs (90 % CL). A resonance enhancement in the decay rate for 0nuECEC might be expected for the 0+-state at 1870.9keV due to degeneracy with the 112Sn ground state. No signal was found resulting in a lower half-life limit of T_1/2 > 1.6 *10^{18} yrs (90 % CL) for this decay. As all the excited state searches are based on gamma-lines, all half-life limits apply for both neutrino and neutrino-less modes. Neutrinoless ground state transitions were searched for in the ECEC and beta+/EC mode and a limit of T_1/2 > 1.5 *10^{18} yrs (90 % CL) was obtained for ECEC decays of 112Sn, whilst the beta+/EC mode results are inconclusive.

J. Dawson; R. Ramaswamy; C. Reeve; J. R. Wilson; K. Zuber

2007-09-27T23:59:59.000Z

82

Experimental research of double beta decay of atomic nuclei  

E-Print Network [OSTI]

Results of several double beta decay experiments, performed with the help of low background crystal scintillators, are presented. In particular, the half-life value of the two-neutrino double beta decay of 116-Cd has been measured as 2.9 10^{19} yr, and the new half-life limit on the neutrinoless double beta decay of 116-Cd has been established as >1.7 10^{23} yr at 90%, which corresponds to a restriction on the neutrino mass <1.7 eV. New half-life bounds on the level of 10^{17}-10^{21} yr were set for double beta processes in 64-Zn, 70-Zn, 106-Cd, 108-Cd, 114-Cd, 136-Ce, 138-Ce, 142-Ce, 160-Gd, 180-W, and 186-W by using low-background CdWO4, GSO, and ZnWO4 crystal scintillators. The claim of discovery of the neutrinoless double beta decay of 76-Ge [Mod. Phys. Lett. A 16 (2001) 2409] was analyzed. The demands of the future high sensitivity double beta decay experiments, aiming to observe the neutrinoless double beta decay or to advance restrictions on the neutrino mass to < 0.01 eV, were considered. Requirements for their sensitivity and discovery potential were formulated. Two projects of double beta experiments with a sensitivity on the level of 10^{26}-10^{27} yr (CAMEO and CARVEL projects) were discussed. Scintillation properties and radioactive contamination of CaWO4, ZnWO4, CdWO4, PbWO4, GSO(Ce), CeF3, yttrium-aluminum garnet doped with neodymium (YAG:Nd) crystal scintillators were studied. Applicability of these scintillators to search for double beta decay was discussed.

F. A. Danevich

2011-12-26T23:59:59.000Z

83

arXiv:1205.5608v1[hep-ex]25May2012 Search for Neutrinoless Double-Beta Decay in 136  

E-Print Network [OSTI]

arXiv:1205.5608v1[hep-ex]25May2012 Search for Neutrinoless Double-Beta Decay in 136 Xe with EXO-200: May 28, 2012) We report on a search for neutrinoless double-beta decay of 136 Xe with EXO-200 in the ±1 region of interest. This sets a lower limit on the half-life of the neutrinoless double-beta decay

Gratta, Giorgio

84

Neutrinoless double beta decay and QCD corrections  

E-Print Network [OSTI]

We consider one loop QCD corrections and renormalization group running of the neutrinoless double beta decay amplitude focusing on the short-range part of the amplitude (without the light neutrino exchange) and find that these corrections can be sizeable. Depending on the operator under consideration, there can be moderate to large cancellations or significant enhancements. We discuss several specific examples in this context. Such large corrections will lead to significant shifts in the half-life estimates which currently are known to be plagued with the uncertainties due to nuclear physics inputs to the physical matrix elements.

Namit Mahajan

2014-01-30T23:59:59.000Z

85

Nuclear moments for the neutrinoless double beta decay  

E-Print Network [OSTI]

A derivation of the neutrinoless double beta decay rate, specially adapted for the nuclear structure calculations, is presented. It is shown that the Fourier-Bessel expansion of the hadronic currents, jointly with the angular momentum recoupling, leads to very simple final expressions for the nuclear form factors. This greatly facilitates the theoretical estimate of the half life. Our approach does not require the closure approximation, which however can be implemented if desired. The method is exemplified for the $\\beta\\beta$ decay $^{48}Ca \\to ^{48}Ti$, both within the QRPA and a shell-model like model.

C. Barbero; F. Krmpotic; D. Tadic

1998-02-23T23:59:59.000Z

86

Beta decay of Neutron-Rich 53-56Ca  

E-Print Network [OSTI]

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

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

2008-01-07T23:59:59.000Z

87

Probing particle and nuclear physics models of neutrinoless double beta decay with different nuclei  

E-Print Network [OSTI]

Half-life estimates for neutrinoless double beta decay depend on particle physics models for lepton flavor violation, as well as on nuclear physics models for the structure and transitions of candidate nuclei. Different models considered in the literature can be contrasted - via prospective data - with a "standard" scenario characterized by light Majorana neutrino exchange and by the quasiparticle random phase approximation, for which the theoretical covariance matrix has been recently estimated. We show that, assuming future half-life data in four promising nuclei (Ge-76, Se-82, Te-130, and Xe-136), the standard scenario can be distinguished from a few nonstandard physics models, while being compatible with alternative state-of-the-art nuclear calculations (at 95% C.L.). Future signals in different nuclei may thus help to discriminate at least some decay mechanisms, without being spoiled by current nuclear uncertainties. Prospects for possible improvements are also discussed.

G. L. Fogli; E. Lisi; A. M. Rotunno

2009-08-06T23:59:59.000Z

88

Probing particle and nuclear physics models of neutrinoless double beta decay with different nuclei  

SciTech Connect (OSTI)

Half-life estimates for neutrinoless double beta decay depend on particle physics models for lepton-flavor violation, as well as on nuclear physics models for the structure and transitions of candidate nuclei. Different models considered in the literature can be contrasted - via prospective data - with a 'standard' scenario characterized by light Majorana neutrino exchange and by the quasiparticle random phase approximation, for which the theoretical covariance matrix has been recently estimated. We show that, assuming future half-life data in four promising nuclei ({sup 76}Ge, {sup 82}Se, {sup 130}Te, and {sup 136}Xe), the standard scenario can be distinguished from a few nonstandard physics models, while being compatible with alternative state-of-the-art nuclear calculations (at 95% C.L.). Future signals in different nuclei may thus help to discriminate at least some decay mechanisms, without being spoiled by current nuclear uncertainties. Prospects for possible improvements are also discussed.

Fogli, G. L.; Rotunno, A. M. [Dipartimento Interateneo di Fisica 'Michelangelo Merlin', Via Amendola 173, 70126 Bari (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Lisi, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy)

2009-07-01T23:59:59.000Z

89

Structure of {sup 81}Ga populated from the {beta}{sup -} decay of {sup 81}Zn  

SciTech Connect (OSTI)

We report on the results of the {beta}-decay of {sup 81}Zn. The experiment was performed at the CERN ISOLDE facility in the framework of a systematic ultra-fast timing investigation of neutron-rich nuclei populated in the decay of Zn. The present analysis included {beta}-gated {gamma}-ray singles and {gamma}-{gamma} coincidences from the decay of {sup 81}Zn to {sup 81}Ga and leads to a new and much more extensive level scheme of {sup 81}Ga. A new half-life of {sup 81}Zn is provided.

Paziy, V.; Mach, H.; Fraile, L. M.; Olaizola, B.; Udias, J. M. [Grupo de Fisica Nuclear, Universidad Complutense, Madrid (Spain); Aprahamian, A.; Bucher, B. [Department of Physics, University of Notre Dame (United States); Bernards, C. [Institut fuer Kernphysik, Koeln, Germany. and Wright Nuclear Structure Laboratory, Yale University, New Haven, CT-06520 (United States); Briz, J. A. [Instituto de Estructura de la Materia, CSIC, Madrid (Spain); Chiara, C. J. [Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland, USA. and Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Dlouhy, Z. [Nuclear Physics Institute of the ASCR, Rez (Czech Republic); Gheorghe, I.; Ghita, D.; Lica, R.; Marginean, N.; Marginean, R.; Stanoiu, M.; Stroe, L. [National Institute for Physics and Nuclear Engineering, Magurele (Romania); Hoff, P. [Department of Chemistry, University of Oslo, Oslo (Norway); Koester, U. [Institut Laue Langevin, 6 Rue Jules Horowitz, F-38042 Grenoble Cedex 9 (France); and others

2013-06-10T23:59:59.000Z

90

Pinning down the mechanism of neutrinoless double beta decay with measurements in different nuclei  

E-Print Network [OSTI]

A measurement of neutrinoless double beta decay in one isotope does not allow to determine the underlying physics mechanism. We discuss the discrimination of mechanisms for neutrinoless double beta decay by comparing ratios of half life measurements for different isotopes. Six prominent examples for specific new physics contributions to neutrinoless double beta decay are analyzed. We find that the change in corresponding ratios of half lives varies from 60% for supersymmetric models up to a factor of 5-20 for extra-dimensional and left-right-symmetric mechanisms.

F. Deppisch; H. Päs

2007-06-25T23:59:59.000Z

91

Pinning Down the Mechanism of Neutrinoless Double {beta} Decay with Measurements in Different Nuclei  

SciTech Connect (OSTI)

A measurement of neutrinoless double beta decay in one isotope does not allow us to determine the underlying physics mechanism. We discuss the discrimination of mechanisms for neutrinoless double beta decay by comparing ratios of half-life measurements for different isotopes. Six prominent examples for specific new physics contributions to neutrinoless double beta decay are analyzed. We find that the change in corresponding ratios of half lives varies from 60% for supersymmetric models up to a factor of 5-20 for extra-dimensional and left-right-symmetric mechanisms.

Deppisch, Frank [Deutsches Elektronen-Synchrotron (DESY), D-22603 Hamburg (Germany); Paes, Heinrich [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, Alabama 35487 (United States)

2007-06-08T23:59:59.000Z

92

Searches for the baryon- and lepton-number violating decays $B^0\\rightarrow\\Lambda_c^ \\ell^-$, $B^-\\rightarrow\\Lambda\\ell^-$, and $B^-\\rightarrow\\bar{\\Lambda}\\ell^-$  

SciTech Connect (OSTI)

Searches for B mesons decaying to final states containing a baryon and a lepton are performed, where the baryon is either {Lambda}{sub c} or {Lambda} and the lepton is a muon or an electron. These decays violate both baryon and lepton number and would be a signature of physics beyond the standard model. No significant signal is observed in any of the decay modes, and upper limits in the range (3.2 - 520) x 10{sup -8} are set on the branching fractions at the 90% confidence level.

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

2011-06-22T23:59:59.000Z

93

Search for the double beta decay of sup 244 Pu  

SciTech Connect (OSTI)

We have searched for the ingrowth of {sup 244}Cm in a 1.45-g sample of {sup 244}Pu. We isolated a curium fraction after an ingrowth period of 1.03 yr; during this time the {sup 244}Pu sample produced {le}0.24 alpha disintegrations per day of {sup 244}Cm (95% C.L.), corresponding to a half-life for the double beta decay of {sup 244}Pu of {ge}1.1{times}10{sup 18} yr.

Moody, K.J.; Lougheed, R.W.; Hulet, E.K. (Nuclear Chemistry Division, Lawrence Livermore National Laboratory, University of California, Livermore, California 94551 (United States))

1992-12-01T23:59:59.000Z

94

The Neutrinoless Double Beta Decay, Physics beyond the Standard Model and the Neutrino Mass  

E-Print Network [OSTI]

The Neutrinoless double beta Decay allows to determine the effectice Majorana electron neutrino mass. For this the following conditions have to be satisfied: (i) The neutrino must be a Majorana particle, i. e. identical to the antiparticle. (ii) The half life has to be measured. (iii)The transition matrix element must be reliably calculated. (iv) The leading mechanism must be the light Majorana neutrino exchange. The present contribution studies the accuracy with which one can calculate by different methods: (1) Quasi-Particle Random Phase Approach (QRPA), (2) the Shell Model (SM), (3) the (before the variation) angular momentum projected Hartree-Fock-Bogoliubov method (PHFB)and the (4) Interacting Boson Approach (IBA). In the second part we investigate how to determine experimentally the leading mechanism for the Neutrinoless Double Beta Decay. Is it (a) the light Majorana neutrino exchange as one assumes to determine the effective Majorana neutrino mass, ist it the heavy left (b) or right handed (c) Majorana neutrino exchange allowed by left-right symmetric Grand Unified Theories (GUT's). Is it a mechanism due to Supersymmetry e.g. with gluino exchange and R-parity and lepton number violating terms. At the end we assume, that Klapdor et al. have indeed measured the Neutrinoless Double Beta Decay(, although contested,)and that the light Majorana neutrino exchange is the leading mechanism. With our matrix elements we obtain then an effective Majorana neutrino mass of: = 0.24 [eV], exp (pm) 0.02; theor. (pm) 0.01 [eV

Amand Faessler

2012-03-16T23:59:59.000Z

95

IMPORTANCE OF NEUTRINOLESS DOUBLE BETA DECAY Abstract  

E-Print Network [OSTI]

number violation in nature and what is its magnitude. The neutrinoless double beta decay experiment can

U. Sarkar; Utpal Sarkar

96

Investigation of double-beta decay with the NEMO-3 detector  

SciTech Connect (OSTI)

The double-beta-decay experiment NEMO-3 has been taking data since February 2003. The aim of this experiment is to search for neutrinoless (0 {nu}{beta}{beta}) decay and investigate two neutrino doublebeta decay in seven different isotopically enriched samples ({sup 100}Mo, {sup 82}Se, {sup 48}Ca, {sup 96}Zr, {sup 116}Cd, {sup 130}Te, and {sup 150}Nd). After analysis of the data corresponding to 3.75 yr, no evidence for 0 {nu}{beta}{beta} decay in the 100Mo and 82Se samples was found. The half-life limits at the 90% C.L. are 1.1 Multiplication-Sign 10{sup 24} and 3.6 Multiplication-Sign 10{sup 23} yr, respectively. Additionally for 0 {nu}{beta}{beta} decay the following limits at the 90% C.L. were obtained, >1.3 Multiplication-Sign 10{sup 22} yr for {sup 48}Ca, >9.2 Multiplication-Sign 10{sup 21} yr for {sup 96}Zr, and >1.8 Multiplication-Sign 10{sup 22} yr for 150Nd. The 2 {nu}{beta}{beta} decay half-life values were precisely measured for all investigated isotopes.

Barabash, A. S., E-mail: barabash@itep.ru [Institute of Theoretical and Experimental Physics (Russian Federation); Brudanin, V. B. [Joint Institute for Nuclear Research (Russian Federation); Collaboration: NEMO Collaboration

2011-02-15T23:59:59.000Z

97

Neutrinoless Quadruple Beta Decay  

E-Print Network [OSTI]

We point out that lepton number violation is possible even if neutrinos are Dirac particles. We illustrate this by constructing a simple model that allows for lepton number violation by four units only. As a consequence, neutrinoless double beta decay is forbidden, but neutrinoless quadruple beta decay is possible: $(A,Z) \\to (A,Z+4) + 4 e^-$. We identify three candidate isotopes for this decay, the most promising one being Nd-150 due to its high $Q_{0\

Julian Heeck; Werner Rodejohann

2013-06-03T23:59:59.000Z

98

Results of the double beta decay experiment NEMO-3  

SciTech Connect (OSTI)

The double beta decay experiment NEMO-3 has taken data from February 2003 to January 2011. The two-neutrino decay half lives were measured for seven different isotopes ({sup 100}Mo, {sup 82}Se, {sup 116}Cd, {sup 150}Nd, {sup 96}Zr, {sup 48}Ca and {sup 130}Te). No evidence for neutrinoless double beta decay is observed. The 0??? half-life limits are found to be T{sub 1/2}{sup 0?}({sup 100}Mo)>1.0×10{sup 24}yr(90%C.L.) and T{sub 1/2}{sup 0?}({sup 82}Se)>3.2×10{sup 23}yr(90%C.L.)

Tretyak, V. I. [Joint Institute for Nuclear Research, 6 Joliot Curie, Dubna (Russian Federation); Collaboration: NEMO-3 Collaboration

2013-12-30T23:59:59.000Z

99

Noncharacteristic half-lives in radioactive decay  

SciTech Connect (OSTI)

Half-lives of radionuclides span more than 50 orders of magnitude. We characterize the probability distribution of this broad-range data set at the same time that we explore a method for fitting power laws and testing goodness-of-fit. It is found that the procedure proposed recently by Clauset et al.[SIAM Rev. 51, 661 (2009)] does not perform well as it rejects the power-law hypothesis even for power-law synthetic data. In contrast, we establish the existence of a power-law exponent with a value around 1.1 for the half-life density, which can be explained by the sharp relationship between decay rate and released energy, for different disintegration types. For the case of alpha emission, this relationship constitutes an original mechanism of power-law generation.

Corral, Alvaro; Font, Francesc [Centre de Recerca Matematica, Edifici Cc, Campus Bellaterra, E-08193 Barcelona (Spain); Camacho, Juan [Grup FESTA, Facultat de Ciencies, Universitat Autonoma de Barcelona, E-08193 Barcelona (Spain)

2011-06-15T23:59:59.000Z

100

Investigation of rare nuclear decays with BaF$_2$ crystal scintillator contaminated by radium  

E-Print Network [OSTI]

The radioactive contamination of a BaF$_2$ scintillation crystal with mass of 1.714 kg was measured over 101 hours in the low-background DAMA/R&D set-up deep underground (3600 m w.e.) at the Gran Sasso National Laboratories of INFN (LNGS, Italy). The half-life of $^{212}$Po (present in the crystal scintillator due to contamination by radium) was measured as $T_{1/2}(^{212}$Po) = 298.8$\\pm$0.8(stat.)$\\pm$1.4(syst.) ns by analysis of the events' pulse profiles. The $^{222}$Rn nuclide is known as 100% decaying via emission of $\\alpha$ particle with $T_{1/2}$ = 3.82 d; however, its $\\beta$ decay is also energetically allowed with $Q_\\beta = 24\\pm21$ keV. Search for decay chains of events with specific pulse shapes characteristic for $\\alpha$ or for $\\beta/\\gamma$ signals and with known energies and time differences allowed us to set, for the first time, the limit on the branching ratio of $^{222}$Rn relatively to $\\beta$ decay as $B_\\beta 8.0$ y). Half-life limits of $^{212}$Pb, $^{222}$Rn and $^{226}$Ra relatively to $2\\beta$ decays are also improved in comparison with the earlier results.

P. Belli; R. Bernabei; F. Cappella; V. Caracciolo; R. Cerulli; F. A. Danevich; A. Di Marco; A. Incicchitti; D. V. Poda; O. G. Polischuk; V. I. Tretyak

2014-07-22T23:59:59.000Z

Note: This page contains sample records for the topic "number half-life decay" from the National Library of EnergyBeta (NLEBeta).
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101

Description of the 2{nu}{nu}{beta}{beta} decay within a fully renormalized proton-neutron quasiparticle random-phase approximation approach with a restored gauge symmetry  

SciTech Connect (OSTI)

A many-body Hamiltonian involving the mean field for a projected spherical single-particle basis, the pairing interactions for alike nucleons, and the dipole-dipole proton-neutron interactions in the particle-hole (ph) channel and the ph dipole pairing potential is treated by the projected gauge fully renormalized proton-neutron quasiparticle random phase approximation approach. The resulting wave functions and energies for the mother and daughter nuclei are used to calculate the 2{nu}{beta}{beta} decay rate and the process half-life. For illustration, the formalism is applied for the decay {sup 100}Mo{yields}{sup 100}Ru. The calculated half-life is in agreement with the corresponding experimental data. The Ikeda sum rule is obeyed.

Raduta, C. M. [Department of Theoretical Physics, Institute of Physics and Nuclear Engineering, P.O. Box MG6, Bucharest RO-077125 (Romania); Raduta, A. A. [Department of Theoretical Physics, Institute of Physics and Nuclear Engineering, P.O. Box MG6, Bucharest RO-077125 (Romania); Academy of Romanian Scientists, 54 Splaiul Independentei, Bucharest RO-050094 (Romania)

2010-12-15T23:59:59.000Z

102

Search for neutrinoless decays of the ? lepton  

E-Print Network [OSTI]

We have searched for neutrinoless ? decays into three charged particles. Evidence of such decays would demonstrate nonconservation of lepton flavor and, in some cases, lepton number. We see no signal for any such neutrinoless ? decays and set upper...

Baringer, Philip S.

1990-02-01T23:59:59.000Z

103

Extra dimensions and neutrinoless double beta decay experiments  

SciTech Connect (OSTI)

The neutrinoless double beta decay is one of the few phenomena, belonging to the nonstandard physics, which is extensively being sought for in experiments. In the present paper the link between the half-life of the neutrinoless double beta decay and theories with large extra dimensions is explored. The use of the sensitivities of currently planned 0{nu}2{beta} experiments: DAMA, CANDLES, COBRA, DCBA, CAMEO, GENIUS, GEM, MAJORANA, MOON, CUORE, EXO, and XMASS, gives the possibility for a nondirect 'experimental' verification of various extra dimensional scenarios. We discuss also the results of the Heidelberg-Moscow Collaboration. The calculations are based on the Majorana neutrino mass generation mechanism in the Arkani-Hamed-Dimopoulos-Dvali model.

Gozdz, Marek; Kaminski, Wieslaw A.; Faessler, Amand [Theoretical Physics Department, Maria Curie-Sklodowska University, Lublin (Poland); Institute fuer Theoretische Physik, Universitaet Tuebingen, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)

2005-05-01T23:59:59.000Z

104

Nuclear Shell Model Analyses and Predictions of Double-Beta Decay Observables  

SciTech Connect (OSTI)

Recent results from neutrino oscillation experiments have convincingly demonstrated that neutrinos have mass and they can mix. The neutrinoless double beta decay is the most sensitive process to determine the absolute scale of the neutrino masses, and the only one that can distinguish whether neutrino is a Dirac or a Majorana particle. A key ingredient for extracting the absolute neutrino masses from neutrinoless double beta decay experiments is a precise knowledge of the nuclear matrix elements (NME) for this process. Newly developed shell model approaches for computing the NME and half-lifes for the two-neutrino and neutrinoless double beta decay modes using modern effective interactions are presented. The implications of the new results on the experimental limits of the effective neutrino mass are discussed by comparing the decays of {sup 48}Ca and {sup 76}Ge.

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

2010-11-24T23:59:59.000Z

105

Yrast structure of the two-proton- and three-neutron-hole nucleus {sup 203}Hg from the decay of a 53/2{sup +} isomer  

SciTech Connect (OSTI)

The decay of a new, 53/2{sup +}, isomer at 8281 keV in {sup 203}Hg has been studied by {gamma} coincidence spectroscopy. A half-life of 146(30) ns was measured. In addition, another isomeric, 39/2{sup +}, level with a half-life of 7.8(1.5) ns was observed. Some elements of the Rydstroem shell-model interaction have been adjusted to reproduce level energies in nuclei with two to four holes in the {sup 208}Pb core. With this interaction, the new states in the five-hole nucleus {sup 203}Hg are reproduced with an rms error of 105 keV.

Szpak, B.; Maier, K. H.; Fornal, B.; Broda, R.; Cieplicka, N.; Krolas, W.; Pawlat, T.; Wrzesinski, J. [Niewodniczanski Institute of Nuclear Physics PAN, Krakow (Poland); Smolkowska, A. S. [Niewodniczanski Institute of Nuclear Physics PAN, Krakow (Poland); Gdansk University of Technology, Gdansk (Poland); Carpenter, M. P.; Janssens, R. V. F.; Zhu, S. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2011-06-15T23:59:59.000Z

106

Shell model analysis of the neutrinoless double-{beta} decay of {sup 48}Ca  

SciTech Connect (OSTI)

The neutrinoless double-{beta} (0{nu}{beta}{beta}) decay process could provide crucial information to determine the absolute scale of neutrino masses, and it is the only one that can establish whether a neutrino is a Dirac or a Majorana particle. A key ingredient for extracting the absolute neutrino masses from 0{nu}{beta}{beta} decay experiments is a precise knowledge of the nuclear matrix elements (NMEs) describing the half-life of this process. We developed a shell model approach for computing the 0{nu}{beta}{beta} decay NME, and we used it to analyze the 0{nu}{beta}{beta} mode of {sup 48}Ca. The dependence of the NME on the short-range correlation parameters, on the average energy of the intermediate states, on the finite-size cutoff parameters, and on the effective interaction used for many-body calculations is discussed.

Horoi, Mihai [Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859 (United States); Stoica, Sabin [Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), 407 Atomistilor, Magurele-Bucharest, R-077125 (Romania)

2010-02-15T23:59:59.000Z

107

Nudat: Nuclear Structure and Decay Data from the National Nuclear Data Center (NNDC)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

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.

108

SuperNEMO - the next generation double beta decay experiment  

E-Print Network [OSTI]

The SuperNEMO experiment is being designed to search for neutrinoless double beta decay to test if neutrinos are Majorana particles. The experimental technique follows that of the currently running NEMO-3 experiment, which successfully combines tracking and calorimetry to measure the topology and energy of the final state electrons. Unique particle identification capabilities of SuperNEMO will be employed with about 100 kg of 82 Se and will reach sensitivity to a half-life of about 2 x 10^26 years, which corresponds to Majorana neutrino masses of about 50 meV, depending on the calculated value of the nuclear matrix element. In this poster, the current status of the SuperNEMO project is presented.

Irina Nasteva; for the SuperNEMO collaboration

2009-09-17T23:59:59.000Z

109

Neutron Interactions in the CUORE Neutrinoless Double Beta Decay Experiment  

SciTech Connect (OSTI)

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

Dolinski, M J

2008-09-24T23:59:59.000Z

110

Neutrinoless Double Beta Decay, the Inverted Hierarchy and Precision Determination of theta(12)  

E-Print Network [OSTI]

Ruling out the inverted neutrino hierarchy with neutrinoless double beta decay experiments is possible if a limit on the effective mass below the minimal theoretically possible value is reached. We stress that this lower limit depends strongly on the value of the solar neutrino mixing angle: it introduces an uncertainty of a factor of 2 within its current 3 sigma range. If an experiment is not background-free, a factor of two in effective mass corresponds to a combined factor of 16 improvement for the experimental parameters running time, detector mass, background level and energy resolution. Therefore, a more precise determination of theta(12) is crucial for the interpretation of experimental results and the evaluation of the potential and requirements for future experiments. We give the required half-lifes to exclude (and touch) the inverted hierarchy regime for all double beta decay isotopes with a Q-value above 2 MeV. The nuclear matrix elements from 6 different groups and, if available, their errors are used and compared. We carefully put the calculations on equal footing in what regards various convention issues. We also use our compilation of matrix elements to give the reachable values of the effective mass for a given half-life value.

Alexander Dueck; Werner Rodejohann; Kai Zuber

2011-04-17T23:59:59.000Z

111

Background Suppression Using Pulse Shape Analysis with a BEGe Detector for Neutrinoless Double Beta Decay Search with GERDA  

SciTech Connect (OSTI)

A pulse shape analysis for distinguishing between double beta decay-like interactions and multiple-scattered photons was performed for the first time using a BEGe-type detector. This discrimination method is included in the research and development for the second phase of the GERDA experiment, since active background suppression techniques are necessary to reach sensitivity for the {sup 76}Ge neutrinoless double beta decay half life of >10{sup 26} years. A suppression of backgrounds in the energy region of interest around the {sup 76}Ge Q{sub {beta}}{sub {beta}} = 2039 keV is demonstrated, with (0.93{+-}0.08)% survival probability for events from {sup 60}Co, (21{+-}3)% for {sup 226}Ra, and (40{+-}2)% for {sup 228}Th. This performance is achieved with (89{+-}1)% acceptance of {sup 228}Th double escape events, which are analogous to double beta decay.

Budjas, Dusan; Schoenert, Stefan [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Chkvorets, Oleg [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Department of Physics, Laurentian University, Ramsey Lake Road, P3E 2C6 Sudbury, Ontario (Canada)

2009-12-17T23:59:59.000Z

112

GERDA, a GERmanium Detector Array for the search for neutrinoless {beta}{beta} decay in 76Ge  

SciTech Connect (OSTI)

The GERDA project, searching for neutrinoless double beta-decay of 76Ge with enriched germanium detectors submerged in a cryogenic bath, has been approved for installation at the Gran Sasso National Laboratory (LNGS), Italy. The GERDA technique is aiming at a dramatic reduction of the background due to radioactive contaminations of the materials surrounding the detectors. This will lead to a sensitivity of about 1026 years on the half-life of neutrinoless double beta decay. Already in the first phase of the experiment, GERDA will be able to investigate with high statistical significance the claimed evidence for neutrinoless double beta decay of 76Ge based on the data of the Heidelberg-Moscow experiment.

Pandola, L.; Tomei, C. [INFN, Laboratori Nazionali del Gran Sasso, S.S. 17 bis km 18.910, 67010 Assergi (AQ) (Italy)

2006-07-11T23:59:59.000Z

113

Search for Neutrinoless Double Beta Decay with NEMO 3 and SuperNEMO  

E-Print Network [OSTI]

Since 2003 the NEMO~3 experiment has been searching for neutrinoless double beta decay using about 10 kg of enriched isotopes. A limit of T_(1/2)(0nu) > 5.8 10**23 years at 90 % CL has been obtained for 100-Mo from the first two years of data. Several measurements of two-neutrino double beta decays have also been performed. A first NEMO 3 measurement of the half-life of 130-Te is presented, giving a value of T_(1/2)(2nu) = (7.6 +- 1.5 (stat) +- 0.8 (syst)) 10**20 years. In parallel, there is an active R&D programme for the SuperNEMO experiment which is expected to commence data taking in 2012-2013 with 100-200 kg of enriched isotopes.

Stefan Soldner-Rembold

2007-10-22T23:59:59.000Z

114

Sensitivity of CUORE to Neutrinoless Double-Beta Decay  

SciTech Connect (OSTI)

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

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

2011-11-23T23:59:59.000Z

115

Measurement of the half-lives of ??As and ??Br high Z test of CVC (Standard Model) via superallowed Fermi decay  

E-Print Network [OSTI]

which describe the P-decay spectra. 29 Initial attempts to fit the 30. 5 MeV and 29. 5 MeV As spectra (66AsR44 and 66AsR50) used CURFIT and the four parameter fitting function: t; t, y(tt) = u+ 5 exp( ? ln 2 ? ) + d exp( ? ln2 ? ). c 446 (4. 6...) The results of the 66AsR44 and 66AsR50 fits, table 1, were encouraging in that they agree well with Alburger's (1978) half-life determination (95. 78 + . 39 msec). The percent errors and the ratios s and & indicated that the second term dominated...

Burch, Robert Harry

1988-01-01T23:59:59.000Z

116

Critical view to ''IGEX {sup 76}Ge neutrinoless double-beta decay experiment: Prospects for next generation experiments''  

SciTech Connect (OSTI)

Recently, a paper entitled 'The IGEX {sup 76}Ge neutrinoless double-beta decay experiment: Prospects for next generation experiments' has been published [Phys. Rev. D 65, 092007 (2002)]. In view of the recently reported evidence for neutrinoless double-beta decay [Mod. Phys. Lett. A 16, 2409 (2001).; Found. Phys. 31, 1181 (2002); Phys. Lett. B 586, 198 (2004).], it is particularly unfortunate that the IGEX paper is rather incomplete in its presentation. We would like to point out in this Comment that and why it would be highly desirable to make more details about the experimental conditions and the analysis of IGEX available. We list some of the main points, which require further explanation. We also point to an arithmetic mistake in the analysis of the IGEX data, the consequence of which are too high half-life limits given in that paper.

Klapdor-Kleingrothaus, H.V.; Dietz, A. [Max-Planck-Institut fuer Kernphysik, Postfach 10 39 80, D-69029 Heidelberg (Germany); Krivosheina, I. V. [Max-Planck-Institut fuer Kernphysik, Postfach 10 39 80, D-69029 Heidelberg (Germany); Radiophysical-Research Institute, Nishnii-Novgorod (Russian Federation)

2004-10-01T23:59:59.000Z

117

Neutrinoless Double Beta Decay and Physics Beyond the Standard Model  

E-Print Network [OSTI]

Neutrinoless double beta decay is the most powerful tool to probe not only for Majorana neutrino masses but for lepton number violating physics in general. We discuss relations between lepton number violation, double beta decay and neutrino mass, review a general Lorentz invariant parametrization of the double beta decay rate, highlight a number of different new physics models showing how different mechanisms can trigger double beta decay, and finally discuss possibilities to discriminate and test these models and mechanisms in complementary experiments.

Frank F. Deppisch; Martin Hirsch; Heinrich Päs

2012-08-03T23:59:59.000Z

118

Additional Nucleon Current Contributions to Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

We have examined the importance of momentum dependent induced nucleon currents such as weak-magnetism and pseudoscalar couplings to the amplitude of neutrinoless double beta decay in the mechanisms of light and heavy Majorana neutrino as well as in that of Majoron emission. Such effects are expected to occur in all nuclear models in the direction of reducing the light neutrino matrix elements by about 30%. To test this we have performed a calculation of the nuclear matrix elements of the experimentally interesting nuclei A = 76, 82, 96, 100, 116, 128, 130, 136 and 150 within the pn-RQRPA. We have found that indeed such corrections vary somewhat from nucleus to nucleus, but in all cases they are greater than 25 percent. In the case of heavy neutrino the effect is much larger (a factor of 3). Combining out results with the best presently available experimental limits on the half-life of the neutrinoless double beta decay we have extracted new limits on the effective neutrino mass (light and heavy) and the effective Majoron coupling constant.

F. Simkovic; G. Pantis; J. D. Vergados; A. Faessler

1999-05-27T23:59:59.000Z

119

Evidence for Correlations Between Nuclear Decay Rates and Earth-Sun Distance  

E-Print Network [OSTI]

Unexplained periodic fluctuations in the decay rates of Si-32 and Ra-226 have been reported by groups at Brookhaven National Laboratory (Si-32), and at the Physikalisch-Technische-Bundesandstalt in Germany (Ra-226). We show from an analysis of the raw data in these experiments that the observed fluctuations are strongly correlated in time, not only with each other, but also with the distance between the Earth and the Sun. Some implications of these results are also discussed, including the suggestion that discrepancies in published half-life determinations for these and other nuclides may be attributable in part to differences in solar activity during the course of the various experiments, or to seasonal variations in fundamental constants.

Jere H. Jenkins; Ephraim Fischbach; John B. Buncher; John T. Gruenwald; Dennis E. Krause; Joshua J. Mattes

2008-08-25T23:59:59.000Z

120

Status of the CUORE and results from the CUORE-0 neutrinoless double beta decay experiments  

E-Print Network [OSTI]

CUORE is a 741 kg array of TeO2 bolometers for the search of neutrinoless double beta decay of 130Te. The detector is being constructed at the Laboratori Nazionali del Gran Sasso, Italy, where it will start taking data in 2015. If the target background of 0.01 counts/keV/kg/y will be reached, in five years of data taking CUORE will have a 1 sigma half life sensitivity of 10E26 y. CUORE-0 is a smaller experiment constructed to test and demonstrate the performances expected for CUORE. The detector is a single tower of 52 CUORE-like bolometers that started taking data in spring 2013. The status and perspectives of CUORE will be discussed, and the first CUORE-0 data will be presented.

Sisti, M; Avignone, F T; Azzolini, O; Balata, M; Banks, T I; Bari, G; Beeman, J; Bellini, F; Bersani, A; Biassoni, M; Brofferio, C; Bucci, C; Cai, X Z; Camacho, A; Caminata, A; Canonica, L; Cao, X G; Capelli, S; Cappelli, L; Carbone, L; Cardani, L; Casali, N; Cassina, L; Chiesa, D; Chott, N; Clemenza, M; Copello, S; Cosmelli, C; Cremonesi, O; Creswick, R J; Cushman, J S; Dafinei, I; Dally, A; Datskov, V; Dell'Oro, S; Deninno, M; Di Domizio, S; di Vacri, M L; Drobizhev, A; Ejzak, L; Fang, D Q; Farach, H A; Faverzani, M; Fernandes, G; Ferri, E; Ferroni, F; Fiorini, E; Franceschi, M A; Freedman, S J; Fujikawa, B K; Giachero, A; Gironi, L; Giuliani, A; Gorla, P; Gotti, C; Gutierrez, T D; Haller, E E; Han, K; Heeger, K M; Hennings-Yeomans, R; Hickerson, K P; Huang, H Z; Kadel, R; Keppel, G; Kolomensky, Yu G; Li, Y L; Ligi, C; Lim, K E; Liu, X; Ma, Y G; Maiano, C; Maino, M; Martinez, M; Maruyama, R H; Mei, Y; Moggi, N; Morganti, S; Napolitano, T; Nastasi, M; Nisi, S; Nones, C; Norman, E B; Nucciotti, A; O'Donnell, T; Orio, F; Orlandi, D; Ouellet, J L; Pagliarone, C E; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pedretti, M; Pessina, G; Pettinacci, V; Piperno, G; Pira, C; Pirro, S; Pozzi, S; Previtali, E; Rosenfeld, C; Rusconi, C; Sala, E; Sangiorgio, S; Scielzo, N D; Smith, A R; Taffarello, L; Tenconi, M; Terranova, F; Tian, W D; Tomei, C; Trentalange, S; Ventura, G; Vignati, M; Wang, B S; Wang, H W; Wielgus, L; Wilson, J; Winslow, L A; Wise, T; Woodcraft, A; Zanotti, L; Zarra, C; Zhang, G Q; Zhu, B X; Zucchelli, S

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "number half-life decay" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


121

Fast decay of a three-quasiparticle isomer in {sup 171}Tm  

SciTech Connect (OSTI)

Incomplete-fusion reactions have been used to study high-spin states in {sup 171}Tm. Gamma rays and conversion electrons were measured using pulsed-beam conditions for enhanced isomer sensitivity. A K{sup {pi}}=19/2{sup +}, three-quasiparticle isomer was identified, with a half-life of 1.7(2){mu}s. The faster than expected transition rates from the isomer can be understood as being due to a chance near-degeneracy, with mixing between the isomeric state and the I{sup {pi}}=19/2{sup +} member of the one-quasiparticle rotational band to which it decays. The implied mixing matrix element is 12(2) eV.

Walker, P. M.; Wood, R. J.; El-Masri, H. M.; Wheldon, C. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Dracoulis, G. D.; Kibedi, T.; Bark, R. A.; Davidson, P. M.; Lane, G. J.; Moon, C. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra ACT0200 (Australia); Bruce, A. M.; Orce, J. N.; Estevez, F. M. Prados [School of Environment and Technology, University of Brighton, Brighton BN2 4GJ (United Kingdom); Byrne, A. P.; Wilson, A. N. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra ACT0200 (Australia); Department of Physics, Australian National University, Canberra ACT0200 (Australia)

2009-04-15T23:59:59.000Z

122

Search for $\\alpha$ decay of $^{151}$Eu to the first excited level of $^{147}$Pm using underground $\\gamma$-ray spectrometry  

E-Print Network [OSTI]

The alpha decay of $^{151}$Eu to the first excited level of $^{147}$Pm ($J^\\pi = 5/2^+$, $E_{exc}=91.1$ keV) was searched for at the HADES underground laboratory ($\\approx 500$ m w.e.). A sample of high purity europium oxide with mass of 303 g and a natural isotopic composition has been measured over 2232.8 h with a high energy resolution ultra-low background n-type semi-planar HPGe detector (40 cm$^3$) with sub-micron deadlayer. The new improved half-life limit has been set as $T_{1/2} \\geq 3.7\\times 10^{18}$ yr at 68% C.L. Possibilities to improve the sensitivity of the experiment, which is already near the theoretical predictions, are discussed. New half-life limit for $\\alpha$ decay of $^{153}$Eu is also set as $T_{1/2} \\geq 5.5\\times 10^{17}$ yr.

Danevich, F A; Hult, M; Marissens, G; Tretyak, V I; Yuksel, A; 10.1140/epja/i2012-12157-7

2013-01-01T23:59:59.000Z

123

Experimental study of the {beta}-delayed neutron decay of {sup 21}N  

SciTech Connect (OSTI)

The first spectroscopic study for the {beta} decay of {sup 21}N is carried out based on {beta}-n, {beta}-{gamma}, and {beta}-n-{gamma} coincidence measurements. The neutron-rich {sup 21}N nuclei are produced by the fragmentation of the E/A=68.8 MeV {sup 26}Mg primary beam on a thick {sup 9}Be target and are implanted into a thin plastic scintillator that also plays the role of {beta} detector. The time of flight of the emitted neutrons following the {beta} decay are measured by the surrounding neutron sphere and neutron wall arrays. In addition, four clover germanium detectors are used to detect the {beta}-delayed {gamma} rays. Thirteen new {beta}-delayed neutron groups are observed with a total branching ratio of 90.5{+-}4.2%. The half-life for the {beta} decay of {sup 21}N is determined to be 82.9{+-}7.5 ms. The level scheme of {sup 21}O is deduced up to about 9 MeV excitation energy. The experimental results for the {beta} decay of {sup 21}N are compared to the shell-model calculations.

Li, Z. H.; Lou, J. L.; Ye, Y. L.; Hua, H.; Jiang, D. X.; Li, X. Q.; Zhang, S. Q.; Zheng, T.; Ge, Y. C.; Kong, Z.; Lv, L. H.; Li, C.; Lu, F.; Fan, F. Y.; Li, Z. Y.; Cao, Z. X.; Ma, L. Y.; Faisal, Q.; Xu, H. S.; Hu, Z. G. [School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)] (and others)

2009-11-15T23:59:59.000Z

124

The {sup 150}Nd({sup 3}He,t) and {sup 150}Sm(t,{sup 3}He) reactions with applications to {beta}{beta} decay of {sup 150}Nd  

SciTech Connect (OSTI)

The {sup 150}Nd({sup 3}He,t) reaction at 140 MeV/u and {sup 150}Sm(t,{sup 3}He) reaction at 115 MeV/u were measured, populating excited states in {sup 150}Pm. The transitions studied populate intermediate states of importance for the (neutrinoless) {beta}{beta} decay of {sup 150}Nd to {sup 150}Sm. Monopole and dipole contributions to the measured excitation-energy spectra were extracted by using multipole decomposition analyses. The experimental results were compared with theoretical calculations obtained within the framework of the quasiparticle random-phase approximation, which is one of the main methods employed for estimating the half-life of the neutrinoless {beta}{beta} decay (0{nu}{beta}{beta}) of {sup 150}Nd. The present results thus provide useful information on the neutrino responses for evaluating the 0{nu}{beta}{beta} and 2{nu}{beta}{beta} matrix elements. The 2{nu}{beta}{beta} matrix element calculated from the Gamow-Teller transitions through the lowest 1{sup +} state in the intermediate nucleus is maximally about half that deduced from the half-life measured in 2{nu}{beta}{beta} direct counting experiments, and at least several transitions through 1{sup +} intermediate states in {sup 150}Pm are required to explain the 2{nu}{beta}{beta} half-life. Because Gamow-Teller transitions in the {sup 150}Sm(t,{sup 3}He) experiment are strongly Pauli blocked, the extraction of Gamow-Teller strengths was complicated by the excitation of the 2({h_bar}/2{pi}){omega}, {Delta}L=0, {Delta}S=1 isovector spin-flip giant monopole resonance (IVSGMR). However, the near absence of Gamow-Teller transition strength made it possible to cleanly identify this resonance, and the strength observed is consistent with the full exhaustion of the non-energy-weighted sum rule for the IVSGMR.

Guess, C. J.; Brown, B. A.; Deaven, J. M.; Hitt, G. W.; Meharchand, R.; Zegers, R. G. T. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824-1321 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States); Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48824 (United States); Adachi, T.; Fujita, H.; Hatanaka, K.; Hirota, K.; Ishikawa, D.; Matsubara, H.; Okamura, H.; Ong, H. J.; Suzuki, T.; Tamii, A.; Yosoi, M.; Zenihiro, J. [Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047 (Japan); Akimune, H. [Department of Physics, Konan University, Okamoto 8-9-1, Higashinada, Kobe 658-8501 (Japan); Algora, A. [Instituto de Fisica Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia (Spain); Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen H-4001 (Hungary)

2011-06-15T23:59:59.000Z

125

Search for 2\\beta\\ decays of 96Ru and 104Ru by ultra-low background HPGe gamma spectrometry at LNGS: final results  

E-Print Network [OSTI]

An experiment to search for double beta decay processes in 96Ru and 104Ru, which are accompanied by gamma rays, has been realized in the underground Gran Sasso National Laboratories of the I.N.F.N. (Italy). Ruthenium samples with masses of about (0.5-0.7) kg were measured with the help of ultra-low background high purity Ge gamma ray spectrometry. After 2162 h of data taking the samples were deeply purified to reduce the internal contamination of 40K. The last part of the data has been accumulated over 5479 h. New improved half life limits on 2\\beta+/\\epsilon \\beta+/2\\epsilon\\ processes in 96Ru have been established on the level of 10^{20} yr, in particular for decays to the ground state of 96Mo: T1/2(2\

Belli, P; Cappella, F; Cerulli, R; Danevich, F A; d'Angelo, S; Incicchitti, A; Kovtun, G P; Kovtun, N G; Laubenstein, M; Poda, D V; Polischuk, O G; Shcherban, A P; Solopikhin, D A; Suhonen, J; Tretyak, V I

2013-01-01T23:59:59.000Z

126

Search for 2? decays of 96Ru and 104Ru by ultra-low background HPGe gamma spectrometry at LNGS: final results  

E-Print Network [OSTI]

An experiment to search for double beta decay processes in 96Ru and 104Ru, which are accompanied by gamma rays, has been realized in the underground Gran Sasso National Laboratories of the I.N.F.N. (Italy). Ruthenium samples with masses of about (0.5-0.7) kg were measured with the help of ultra-low background high purity Ge gamma ray spectrometry. After 2162 h of data taking the samples were deeply purified to reduce the internal contamination of 40K. The last part of the data has been accumulated over 5479 h. New improved half life limits on 2\\beta+/\\epsilon \\beta+/2\\epsilon\\ processes in 96Ru have been established on the level of 10^{20} yr, in particular for decays to the ground state of 96Mo: T1/2(2\

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

2013-02-28T23:59:59.000Z

127

Radiative ?(1S) decays  

E-Print Network [OSTI]

— wW~ ii~ ~ + v~ 1''&WV'' V 0.20 0.45 0.70 ~y ~ EBFA~ 0.95 l.20 FIG. 4. Energy spectrum (normalized to beam energy) for Y~y2(h+h ) event candidates, with continuum data and ex- pected background from Y~m 2(h +h ) overplotted. 40 30— ~ 20— LLI IO— hl...PHYSICAL REVIEW 0 VOLUME 41, NUMBER 5 Radiative T(lS) decays 1 MARCH 1990 R. Fulton, M. Hempstead, T. Jensen, D. R. Johnson, H. Kagan, R. Kass, F. Morrow, and J. Whitmore Ohio State University, Columbus, Ohio 43210 W.-Y. Chen, J. Dominick, R. L. Mc...

Baringer, Philip S.

1990-03-01T23:59:59.000Z

128

Radioactive decay data tables  

SciTech Connect (OSTI)

The estimation of radiation dose to man from either external or internal exposure to radionuclides requires a knowledge of the energies and intensities of the atomic and nuclear radiations emitted during the radioactive decay process. The availability of evaluated decay data for the large number of radionuclides of interest is thus of fundamental importance for radiation dosimetry. This handbook contains a compilation of decay data for approximately 500 radionuclides. These data constitute an evaluated data file constructed for use in the radiological assessment activities of the Technology Assessments Section of the Health and Safety Research Division at Oak Ridge National Laboratory. The radionuclides selected for this handbook include those occurring naturally in the environment, those of potential importance in routine or accidental releases from the nuclear fuel cycle, those of current interest in nuclear medicine and fusion reactor technology, and some of those of interest to Committee 2 of the International Commission on Radiological Protection for the estimation of annual limits on intake via inhalation and ingestion for occupationally exposed individuals.

Kocher, D.C.

1981-01-01T23:59:59.000Z

129

Operator Analysis of Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

We study the effective operators of the standard model fields which would yield an observable rate of neutrinoless double beta decay. We particularly focus on the possibility that neutrinoless double beta decay is dominantly induced by lepton-number-violating higher dimensional operators other than the Majorana neutrino mass. Our analysis can be applied to models in which neutrinoless double beta decay is induced either by a strong dynamics or by quantum gravity effects at a fundamental scale near the TeV scale as well as the conventional models in which neutrinoless double beta decay is induced by perturbative renormalizable interactions.

Kiwoon Choi; Kwang Sik Jeong; Wan Young Song

2002-07-19T23:59:59.000Z

130

Neutrinoless Double Beta Decay and Neutrino Masses  

E-Print Network [OSTI]

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

Michael Duerr

2012-06-04T23:59:59.000Z

131

Semileptonic Decays  

SciTech Connect (OSTI)

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

Luth, Vera G.; /SLAC

2012-10-02T23:59:59.000Z

132

Neutrinoless double beta decay and nuclear matrix elements  

SciTech Connect (OSTI)

The fundamental importance of searching for neutrinoless double-beta decay (0{nu}{beta}{beta}-decay) is widely recognized. Observation of the decay would tell us that the total lepton number is not conserved and that, consequently, neutrinos are massive Majorana fermions. The 0{nu}{beta}{beta}-decay is discussed in context of neutrino oscillation data. The perspectives of the experimental 0{nu}{beta}{beta}-decay searches are analyzed. The importance of reliable determination of the 0{nu}{beta}{beta}-decay nuclear matrix elements is pointed out.

Simkovic, Fedor [BLTP, JINR Dubna, 141980 Dubna, Moscow region (Russian Federation); Comenius University, Mlynska dolina, Bratislava (Slovakia)

2011-11-23T23:59:59.000Z

133

Neutrinoless Double Beta Decay Experiments  

E-Print Network [OSTI]

Neutrinoless double beta decay is the only process known so far able to test the neutrino intrinsic nature: its experimental observation would imply that the lepton number is violated by two units and prove that neutrinos have a Majorana mass components, being their own anti-particle. While several experiments searching for such a rare decay have been performed in the past, a new generation of experiments using different isotopes and techniques have recently released their results or are taking data and will provide new limits, should no signal be observed, in the next few years to come. The present contribution reviews the latest public results on double beta decay searches and gives an overview on the expected sensitivities of the experiments in construction which will be able to set stronger limits in the near future.

Alberto Garfagnini

2014-08-11T23:59:59.000Z

134

Neutrinoless Double Beta Decay Experiments  

E-Print Network [OSTI]

Neutrinoless double beta decay is the only process known so far able to test the neutrino intrinsic nature: its experimental observation would imply that the lepton number is violated by two units and prove that neutrinos have a Majorana mass components, being their own anti-particle. While several experiments searching for such a rare decay have been performed in the past, a new generation of experiments using different isotopes and techniques have recently released their results or are taking data and will provide new limits, should no signal be observed, in the next few years to come. The present contribution reviews the latest public results on double beta decay searches and gives an overview on the expected sensitivities of the experiments in construction which will be able to set stronger limits in the near future.

Garfagnini, Alberto

2014-01-01T23:59:59.000Z

135

Neutrino Decay and Neutrinoless Double Beta Decay in a 3-3-1 Model  

E-Print Network [OSTI]

In this work we show that the implementation of spontaneous breaking of the lepton number in the 3-3-1 model with right-handed neutrinos gives rise to fast neutrino decay with majoron emission and generates a bunch of new contributions to the neutrinoless double beta decay.

Alex G. Dias; A. Doff; C. A. de S. Pires; P. S. Rodrigues da Silva

2005-08-11T23:59:59.000Z

136

Neutrino decay and neutrinoless double beta decay in a 3-3-1 model  

SciTech Connect (OSTI)

In this work we show that the implementation of spontaneous breaking of the lepton number in the 3-3-1 model with right-handed neutrinos gives rise to fast neutrino decay with Majoron emission and generates a bunch of new contributions to the neutrinoless double beta decay.

Dias, Alex G. [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66.318, 05315-970, Sao Paulo-SP (Brazil); Doff, A. [Instituto de Fisica Teorica, Universidade Estadual Paulista, Rua Pamplona 145, 01405-900 Sao Paulo-SP (Brazil); Pires, C.A. de S; Rodrigues da Silva, P.S. [Departamento de Fisica, Universidade Federal da Paraiba, Caixa Postal 5008, 58051-970, Joao Pessoa-PB (Brazil)

2005-08-01T23:59:59.000Z

137

High-Precision Measurements of the Superallowed Beta+ Decays of 38Ca and 46V  

E-Print Network [OSTI]

Ca transition into the desired range of 0.1%. With our half-life and superallowed branching ratio results for ł?Ca, we obtain the Ft to be 3072(17) s, in good agreement with the conserved vector current expectation. The half-life of ??V has been...

Park, Hyo-In

2012-10-19T23:59:59.000Z

138

Exotic decay model and alpha decay studies  

SciTech Connect (OSTI)

In exotic decay studies, the lifetime of alpha emission occurs crucially in the branching ratio calculation. In this work, we extend our previous exotic decay model to calculate the same. But, in this case unlike in the exotic decay, the redistribution of charge for given masses of the fragments has to be taken into account since the charge-to-mass ratio of the alpha fragment differs from that of the parent nucleus. We have therefore modified the Yukawa-plus-exponential potential in the post-scission region in our model suitably so as to allow the required charge redistribution among the fragments in the region between sharp contact and the point up to which the finite-range effects persist. The success of this model for alpha decay is as good as for the exotic decay studies.

Shanmugam, G.; Kamalaharan, B. (Department of Physics, Presidency College, Madras 600005, India (IN))

1990-04-01T23:59:59.000Z

139

Investigation of Double Beta Decay of 100Mo to Excited States of 100Ru  

SciTech Connect (OSTI)

Double beta decay of 100Mo to the excited states of daughter nuclei has been studied using a 600 cm3 low-background HPGe detector and an external source consisting of 2588 g of 97.5% enriched metallic 100Mo, which was formerly inside the NEMO-3 detector and used for the NEMO-3 measurements of 100Mo. The half-life for the two-neutrino double beta decay of 100Mo to the excited View the MathML source state in 100Ru is measured to be T1/2=[7.5±0.6(stat)±0.6(syst)]·1020 yr. For other (0?+2?) transitions to the View the MathML source, View the MathML source, View the MathML source, View the MathML source and View the MathML source levels in 100Ru, limits are obtained at the level of ~(0.25–1.1)·1022 yr.

A. J. Caffrey; The NEMO-3 Collaboration

2014-05-01T23:59:59.000Z

140

Predictions of Alpha Decay Half lives of Heavy and Superheavy Elements  

E-Print Network [OSTI]

Theoretical estimates for the lifetimes of several isotopes of heavy elements with Z=102-120 are presented by calculating the quantum mechanical tunneling probability in a WKB framework and using microscopic nucleus-nucleus potential obtained by folding the densities of interacting nuclei with the DDM3Y effective nuclear interaction. The $\\alpha$-decay half lives calculated in this formalism using the experimental $Q$-values are in good agreement over a wide range of experimental data. Half lives are also calculated using $Q$-values extracted from two mass formulae. The Viola-Seaborg-Sobiczewski (VSS) estimates of $\\alpha$-decay half lives with the same $Q$-values are presented for comparison. The half life calculations are found to be quite sensitive to the choice of $Q$-values. Comparison with the experimental data delineates the inadequacies of older mass predictions in the domain of heavy and superheavy elements as compared to the newer one by Muntian-Hofmann-Patyk-Sobiczewski, and highlights necessity of a more accurate mass formula which can predict $Q$-values with even higher precision.

C. Samanta; P. Roy Chowdhury; D. N. Basu

2007-05-28T23:59:59.000Z

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


141

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

SciTech Connect (OSTI)

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

Kogler, Laura

2011-11-03T23:59:59.000Z

142

First bolometric measurement of the two neutrino double beta decay of $^{100}$Mo with a ZnMoO$_4$ crystals array  

E-Print Network [OSTI]

The large statistics collected during the operation of a ZnMoO$_4$ array, for a total exposure of 1.3 kg $\\cdot$ day of $^{100}$Mo, allowed the first bolometric observation of the two neutrino double beta decay of $^{100}$Mo. The observed spectrum of each crystal was reconstructed taking into account the different background contributions due to environmental radioactivity and internal contamination. The analysis of coincidences between the crystals allowed the assignment of constraints to the intensity of the different background sources, resulting in a reconstruction of the measured spectrum down to an energy of $\\sim$300 keV. The half-life extracted from the data is T$_{1/2}^{2\

L. Cardani; L. Gironi; N. Ferreiro Iachellini; L. Pattavina; J. W. Beeman; F. Bellini; N. Casali; O. Cremonesi; I. Dafinei; S. Di Domizio; F. Ferroni; E. Galashov; C. Gotti; S. Nagorny; F. Orio; G. Pessina; G. Piperno; S. Pirro; E. Previtali; C. Rusconi; C. Tomei; M. Vignati

2014-04-30T23:59:59.000Z

143

Baryon helicity in B decay  

SciTech Connect (OSTI)

We extend the perturbative argument of helicity amplitudes to the two-body baryonic decays of B decays.

Suzuki, Mahiko

2005-05-13T23:59:59.000Z

144

Importance of neutrinoless double beta decay  

E-Print Network [OSTI]

A natural explanation for the smallness of the neutrino mass requires them to be Majorana particles violating lepton number by two units. Since lepton number violation can have several interesting consequences in particle physics and cosmology, it is of utmost importance to find out if there is lepton number violation in nature and what is its magnitude. The neutrinoless double beta decay experiment can answer these questions: if there is lepton number violation and if neutrinos are Majorana particles. In addition, the magnitude of neutrinoless double beta decay will constrain any other lepton number violating processes. This lepton number violation may also be relatd to the matter-antimatter asymmetry of the universe, dark matter and cosmological constant.

Utpal Sarkar

2007-12-17T23:59:59.000Z

145

NEUTRINOLESS DOUBLE-DECAY Revised August 2011 by P. Vogel (Caltech) and A. Piepke  

E-Print Network [OSTI]

­ 1­ NEUTRINOLESS DOUBLE- DECAY Revised August 2011 by P. Vogel (Caltech) and A. Piepke (University of Alabama). Neutrinoless double-beta (0) decay would signal vio- lation of total lepton number conservation

146

NEUTRINOLESS DOUBLE-DECAY Revised August 2009 by P. Vogel (Caltech) and A. Piepke  

E-Print Network [OSTI]

­ 1­ NEUTRINOLESS DOUBLE- DECAY Revised August 2009 by P. Vogel (Caltech) and A. Piepke (University of Alabama). Neutrinoless double-beta (0) decay would signal vio- lation of total lepton number conservation

147

Double Beta Decay: Scintillators  

E-Print Network [OSTI]

Scintillator detectors can be used in experiments searching for neutrinoless double beta decay. A wide variety of double beta decay candidate isotopes can be made into scintillators or can be loaded into scintillators. Experimental programs developing liquid xenon, inorganic crystals, and Nd-loaded liquid scintillator are described in this review. Experiments with 48Ca and 150Nd benefit from their high endpoint which places the neutrinoless double beta decay signal above most backgrounds from natural radioactivity.

Mark C. Chen

2008-10-20T23:59:59.000Z

148

Double beta decay and neutrino mass models  

E-Print Network [OSTI]

Neutrinoless double beta decay allows to constrain lepton number violating extensions of the standard model. If neutrinos are Majorana particles, the mass mechanism will always contribute to the decay rate, however, it is not a priori guaranteed to be the dominant contribution in all models. Here, we discuss whether the mass mechanism dominates or not from the theory point of view. We classify all possible (scalar-mediated) short-range contributions to the decay rate according to the loop level, at which the corresponding models will generate Majorana neutrino masses, and discuss the expected relative size of the different contributions to the decay rate in each class. We also work out the phenomenology of one concrete 2-loop model in which both, mass mechanism and short-range diagram, might lead to competitive contributions, in some detail.

Helo, J C; Ota, T; Santos, F A Pereira dos

2015-01-01T23:59:59.000Z

149

Recent Results in Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

The search for neutrinoless double beta decay is a rich source for new physics. The observation of this decay will lead to understanding of the absolute mass scale of neutrinos, the Majorana nature of the neutrino (whether the neutrino is its own anti-particle), and lepton number violation. Double beta decay is being investigated around the world by several experiments using different candidate isotopes. There has been much progress made in experimental techniques recently such that achieving sensitivity to neutrino masses at 50 meV and below will be possible in the near future. A summary of recent results in neutrinoless double beta decay is discussed with a look toward the experimental goals for the future.

Lisa J. Kaufman

2013-05-14T23:59:59.000Z

150

B decays and Supersymmetry  

E-Print Network [OSTI]

I discuss how supersymmetry affects various observables in B decays, and point out the interesting channels in the context of B factories.

Anirban Kundu

2002-05-10T23:59:59.000Z

151

Probing lepton number violation on three frontiers  

SciTech Connect (OSTI)

Neutrinoless double beta decay constitutes the main probe for lepton number violation at low energies, motivated by the expected Majorana nature of the light but massive neutrinos. On the other hand, the theoretical interpretation of the (non-)observation of this process is not straightforward as the Majorana neutrinos can destructively interfere in their contribution and many other New Physics mechanisms can additionally mediate the process. We here highlight the potential of combining neutrinoless double beta decay with searches for Tritium decay, cosmological observations and LHC physics to improve the quantitative insight into the neutrino properties and to unravel potential sources of lepton number violation.

Deppisch, Frank F. [Department of Physics and Astronomy, University College London (United Kingdom)

2013-12-30T23:59:59.000Z

152

Decay of charged fields in de Sitter spacetime  

E-Print Network [OSTI]

We study the decay of charged scalar and spinor fields around Reissner-Nordstrom black holes in de Sitter spacetime through calculations of quasinormal frequencies of the fields. The influence of the parameters of the black hole (charge, mass), of the decaying fields (charge, spin), and of the spacetime (cosmological constant) on the decay is analyzed. The analytic formula for calculation quasinormal frequencies for a large multipole number (eikonal approximation) is derived both for the spinor and scalar fieldss.

A. A. Smirnov

2005-05-12T23:59:59.000Z

153

Production and decay properties of the 1.9-s isomeric state in {sup 261}Rf  

SciTech Connect (OSTI)

The 1.9-s isomeric state ({sup 261}Rf{sup b}) in {sup 261}Rf was directly populated in the {sup 248}Cm({sup 18}O,5n){sup 261}Rf{sup b} reaction. Alpha and spontaneous fission (SF) decays of {sup 261}Rf{sup b}, as well as the 68-s state {sup 261}Rf{sup a}, was investigated with a rotating wheel apparatus under low background conditions attained by a gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator. An identification of {sup 261}Rf{sup b} was based on {alpha}-{alpha} correlations linking {alpha} decays of {sup 261}Rf{sup b} and its daughter {sup 257}No. The {alpha}-particle energy of {sup 261}Rf{sup b} was measured to be 8.52 {+-} 0.05 MeV. The half-life was determined to be 1.9 {+-} 0.4 s based on both 8.52-MeV {alpha} and SF decays. The {alpha} and SF branches are 0.27 {+-} 0.06 and 0.73 {+-} 0.06, respectively. The cross section for the {sup 248}Cm({sup 18}O,5n){sup 261}Rf{sup b} reaction is {sigma}({sup 261}Rf{sup b}) = 11 {+-} 2 nb at 95.1 MeV, which gives a cross-section ratio of {sigma}({sup 261}Rf{sup a})/{sigma}({sup 261}Rf{sup b}) = 1.1 {+-} 0.2.

Haba, H.; Kaji, D.; Kikunaga, H.; Kudou, Y.; Morimoto, K.; Morita, K.; Ozeki, K.; Sumita, T.; Yoneda, A.; Kasamatsu, Y.; Komori, Y.; Ooe, K.; Shinohara, A. [Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

2011-03-15T23:59:59.000Z

154

Double beta decay experiments  

E-Print Network [OSTI]

The present status of double beta decay experiments are reviewed. The results of the most sensitive experiments, NEMO-3 and CUORICINO, are discussed. Proposals for future double beta decay experiments are considered. In these experiments sensitivity for the effective neutrino mass will be on the level of (0.1-0.01) eV.

A. S. Barabash

2006-02-22T23:59:59.000Z

155

Double beta decay experiments  

E-Print Network [OSTI]

The present status of double beta decay experiments is reviewed. The results of the most sensitive experiments are discussed. Proposals for future double beta decay experiments with a sensitivity to the $$ at the level of (0.01--0.1) eV are considered.

A. S. Barabash

2011-07-28T23:59:59.000Z

156

Rare hadronic B decays  

E-Print Network [OSTI]

Rare hadronic B-meson decays allow us to study CP violation. The class of B decays final states containing two vector mesons provides a rich set of angular correlation observables to study. This article reviews some of the recent experimental results from the BaBar and Belle collaborations.

A. J. Bevan

2006-06-02T23:59:59.000Z

157

One Year of Evidence for Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

The present experimental status in the search for neutrinoless double beta decay is reviewed, with emphasis on the first indication for neutrinoless double beta decay found in the HEIDELBERG-MOSCOW experiment, giving first evidence for lepton number violation and a Majorana nature of the neutrinos. Future perspectives of the field are briefly outlined.

H. V. Klapdor-Kleingrothaus

2003-02-26T23:59:59.000Z

158

Rare B Decays and B Decay Dynamics  

E-Print Network [OSTI]

I present some recent measurements of B meson decay rates to leptonic and charmless hadronic final states, as well as of CP-violation charge asymmetries and other features. I sketch the theoretical frameworks used to predict these, and indicate the level of agreement of the estimates with experiment.

William T. Ford

2005-10-20T23:59:59.000Z

159

Superallowed 0+ --> 0+ nuclear beta decays: 2014 critical survey, with precise results for Vud and CKM unitarity  

E-Print Network [OSTI]

A new critical survey is presented of all half-life, decay-energy and branching-ratio measurements related to 20 superallowed 0+ --> 0+ beta decays. Included are 222 individual measurements of comparable precision obtained from 177 published references. Compared with our last review in 2008, we have added results from 24 new publications and eliminated 9 references, the results from which having been superseded by much more precise modern data. We obtain world-average ft-values for each of the eighteen transitions that have a complete set of data, then apply radiative and isospin-symmetry-breaking corrections to extract corrected Ft values. Fourteen of these Ft values now have a precision of order 0.1% or better. In the process of obtaining these results we carefully evaluate the available calculations of the isospin-symmetry-breaking corrections by testing the extent to which they lead to Ft values consistent with conservation of the vector current (CVC). Only one set of calculations satisfactorily meets thi...

Hardy, J C

2014-01-01T23:59:59.000Z

160

High sensitivity double beta decay study of 116-Cd and 100-Mo with the BOREXINO Counting Test Facility (CAMEO project)  

E-Print Network [OSTI]

The unique features (super-low background and large sensitive volume) of the CTF and BOREXINO set ups are used in the CAMEO project for a high sensitivity study of 100-Mo and 116-Cd neutrinoless double beta decay. Pilot measurements with 116-Cd and Monte Carlo simulations show that the sensitivity of the CAMEO experiment (in terms of the half-life limit for neutrinoless double beta decay) is (3-5) 10^24 yr with a 1 kg source of 100-Mo (116-Cd, 82-Se, and 150-Nd) and about 10^26 yr with 65 kg of enriched 116-CdWO_4 crystals placed in the liquid scintillator of the CTF. The last value corresponds to a limit on the neutrino mass of less than 0.06 eV. Similarly with 1000 kg of 116-CdWO_4 crystals located in the BOREXINO apparatus the neutrino mass limit can be pushed down to m_nu<0.02 eV.

G. Bellini; B. Caccianiga; M. Chen; F. A. Danevich; M. G. Giammarchi; V. V. Kobychev; B. N. Kropivyansky; E. Meroni; L. Miramonti; A. S. Nikolayko; L. Oberauer; O. A. Ponkratenko; V. I. Tretyak; S. Yu. Zdesenko; Yu. G. Zdesenko

2000-07-11T23:59:59.000Z

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


161

Search for neutrinoless ? decays: ??e? and ????  

E-Print Network [OSTI]

A search for the lepton-family-number-violating decays ??e? and ???? has been performed using CLEO II data. No evidence of a signal has been found and the corresponding upper limits are B(??e?)<2.7×10(-6) and B(????)<3.0×10(-6) at 90% C.L....

Baringer, Philip S.

1997-04-01T23:59:59.000Z

162

Nuclear physics aspects of double beta decay  

E-Print Network [OSTI]

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

Petr Vogel

2008-07-15T23:59:59.000Z

163

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

E-Print Network [OSTI]

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

The Majorana collaboration

2003-11-13T23:59:59.000Z

164

First observation of {alpha} decay of {sup 190}Pt to the first excited level (E{sub exc}=137.2 keV) of {sup 186}Os  

SciTech Connect (OSTI)

The {alpha} decays of naturally occurring platinum isotopes, which are accompanied by the emission of {gamma} quanta, have been searched for deep underground (3600 m water equivalent) at the Gran Sasso National Laboratories of the INFN (Italy). A sample of Pt with a mass of 42.5 g and a natural isotopic composition has been measured with a low background HP Ge detector (468 cm{sup 3}) during 1815 h. The {alpha} decay of {sup 190}Pt to the first excited level of {sup 186}Os (J{sup {pi}}=2{sup +}, E{sub exc}=137.2 keV) has been observed for the first time, with the half-life determined as T{sub 1/2}=2.6{sub -0.3}{sup +0.4}(stat.){+-}0.6(syst.)x10{sup 14} yr. The T{sub 1/2} limits for the {alpha} decays of other Pt isotopes have been determined at the level of T{sub 1/2}{approx_equal}10{sup 16}-10{sup 20} yr. These limits have been set for the first time or they are better than those known from earlier experiments.

Belli, P. [INFN, Sezione di Roma Tor Vergata, I-00133 Rome (Italy); Bernabei, R. [INFN, Sezione di Roma Tor Vergata, I-00133 Rome (Italy); Dipartimento di Fisica, Universita di Roma Tor Vergata, I-00133 Rome (Italy); Cappella, F. [INFN, Sezione di Roma La Sapienza, I-00185 Rome (Italy); Dipartimento di Fisica, Universita di Roma La Sapienza, I-00185 Rome (Italy); Cerulli, R.; Laubenstein, M.; Nisi, S. [INFN, Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ) (Italy); Danevich, F. A.; Nagorny, S. S.; Polischuk, O. G.; Tretyak, V. I. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Incicchitti, A. [INFN, Sezione di Roma La Sapienza, I-00185 Rome (Italy)

2011-03-15T23:59:59.000Z

165

Permanent Home Number: Residential Number  

E-Print Network [OSTI]

Permanent Home Number: Residential Number: Mobile: Please update my contact details. Signature nominated correspondence address as indicated below. Permanent Home Adress Residential Address Other Address (Must not be a PO Box) Residential Address (Must not be a PO Box) Other - Postal/Optional Address

Viglas, Anastasios

166

UNIT NUMBER:  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

193 UNIT NUMBER: 197 UNIT NAME: CONCRETE RUBBLE PILE (30) REGULATORY STATUS: AOC LOCATION: Outside plant security fence, north of the plant on Big Bayou Creek on private property....

167

Neutrinoless double beta decay and neutrino masses  

SciTech Connect (OSTI)

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

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

2012-07-27T23:59:59.000Z

168

RARE KAON DECAYS.  

SciTech Connect (OSTI)

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.

LITTENBERG, L.

2005-07-19T23:59:59.000Z

169

Neutrinoless double beta decay  

E-Print Network [OSTI]

The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations are presented as well as the current status of experiments. Finally an outlook towards the future, work on nuclear matrix elements and alternative processes is given.

K. Zuber

2012-01-23T23:59:59.000Z

170

Neutrinoless Double $?$-Decay  

E-Print Network [OSTI]

The neutrinoless double $\\beta$-decay is reviewed. Model independent evidence in favor of neutrino masses and mixing is briefly summarized. The data of the recent experiments on the search for $0\

S. M. Bilenky

2004-03-23T23:59:59.000Z

171

Constraining Decaying Dark Matter  

E-Print Network [OSTI]

We revisited the decaying dark matter (DDM) model, in which one collisionless particle decays early into two collisionless particles, that are potentially dark matter particles today. The effect of DDM will be manifested in the cosmic microwave background (CMB) and structure formation. With a systematic modification of CMB calculation tool \\texttt{camb}, we can numerically calculated this effect, and compare it to observations. Further Markov Chain Monte Carlo \\texttt{cosmomc} runnings update the constraints in that model: the free streaming length $\\lambda_{FS}\\lesssim0.5$Mpc for nonrelativistic decay, and $((M_{DDM}/keV) Y)^2 (T_d/yr)\\lesssim5\\times10^{-5}$ for relativistic decay.

Ran Huo

2011-07-13T23:59:59.000Z

172

Charmless B Decays  

SciTech Connect (OSTI)

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.

Gradl, Wolfgang; /Edinburgh U.

2007-03-06T23:59:59.000Z

173

Double Beta Decay  

E-Print Network [OSTI]

The motivation, present status, and future plans of the search for the neutrinoless double beta decay are reviewed. It is argued that, motivated by the recent observations of neutrino oscillations, there is a reasonable hope that neutrinoless double beta decay corresponding to the neutrino mass scale suggested by oscillations, of about 50 meV, actually exists. The challenges to achieve the sensitivity corresponding to this mass scale, and plans to overcome them, are described.

Steven R. Elliott; Petr Vogel

2002-02-27T23:59:59.000Z

174

Empirical Survey of Neutrinoless Double Beta Decay Matrix Elements  

E-Print Network [OSTI]

Neutrinoless double beta decay has been the subject of intensive theoretical work as it represents the only practical approach to discovering whether neutrinos are Majorana particles or not, and whether lepton number is a conserved quantum number. Available calculations of matrix elements and phase-space factors are reviewed from the perspective of a future large-scale experimental search for neutrinoless double beta decay. Somewhat unexpectedly, a uniform inverse correlation between phase space and the square of the nuclear matrix element emerges. As a consequence, no isotope is either favored or disfavored; all have qualitatively the same decay rate per unit mass for any given value of the Majorana mass.

R. G. H. Robertson

2013-01-07T23:59:59.000Z

175

Phenomenology of neutrinoless double beta decay  

E-Print Network [OSTI]

Neutrinoless double beta decay violates lepton number by two units, a positive observation therefore necessarily implies physics beyond the standard model. Here, three possible contributions to neutrinoless double beta decay are briefly reviewed: (a) The mass mechanism and its connection to neutrino oscillations; (b) Left-right symmetric models and the lower limit on the right-handed W boson mass; and (c) R-parity violating supersymmetry. In addition, the recently published ``extended black box'' theorem is briefly discussed. Combined with data from oscillation experiments this theorem provides proof that the neutrinoless double beta decay amplitude must receive a non-zero contribution from the mass mechanism, if neutrinos are indeed Majorana particles.

M. Hirsch

2006-09-15T23:59:59.000Z

176

Rare K decays: Challenges and Perspectives  

E-Print Network [OSTI]

At this stage of the LHC program, the prospect for a new physics signal in the very rare K ---> pi nu nu bar decays may be dented, but remains well alive thanks to their intrinsic qualities. First, these decays are among the cleanest observables in the quark flavor sector. When combined with their terrible suppression in the Standard Model, they thus offer uniquely sensitive probes. Second, the LHC capabilities are not ideal for all kinds of new physics, even below the TeV scale. For example, rather elusive scenarios like natural-SUSY-like hierarchical spectrum, baryon number violation, or new very light but very weakly interacting particles may well induce deviations in rare K decays. Even though experimentalists should brace themselves for tiny deviations, these modes thus have a clear role to play in the LHC era.

Christopher Smith

2014-09-22T23:59:59.000Z

177

Chapter 11 The Dynamic Planet  

E-Print Network [OSTI]

The geologic time scale: Eon>Era>Period>Epoch Largest Smallest #12; Absolute time: The actual number of years-life of U238 1.0 0.5 0 Absolute Time Uranium 238 Uranium 235 Plot is not to scale. Half-life, the decay. #12;Geologic Time Scale #12;Holocene Holocene is the youngest epoch in the geologic time scale

Pan, Feifei

178

Probing new physics in the neutrinoless double beta decay using electron angular correlation  

SciTech Connect (OSTI)

The angular correlation of the electrons emitted in the neutrinoless double beta decay (0{nu}2{beta}) is presented using a general Lorentz invariant effective Lagrangian for the leptonic and hadronic charged weak currents. We show that the coefficient K in the angular correlation d{gamma}/dcos{theta}{proportional_to}(1-Kcos{theta}) is essentially independent of the nuclear matrix element models and present its numerical values for the five nuclei of interest ({sup 76}Ge, {sup 82}Se, {sup 100}Mo, {sup 130}Te, and {sup 136}Xe), assuming that the 0{nu}2{beta} decays in these nuclei are induced solely by a light Majorana neutrino, {nu}{sub M}. This coefficient varies between K=0.81 (for the {sup 76}Ge nucleus) and K=0.88 (for the {sup 82}Se and {sup 100}Mo nuclei), calculated taking into account the effects from the nucleon recoil, the S and P waves for the outgoing electrons and the electron mass. Deviation of K from its values derived here would indicate the presence of new physics (NP) in addition to a light Majorana neutrino, and we work out the angular coefficients in several {nu}{sub M}+NP scenarios for the {sup 76}Ge nucleus. As an illustration of the correlations among the 0{nu}2{beta} observables (half-life T{sub 1/2}, the coefficient K, and the effective Majorana neutrino mass ||) and the parameters of the underlying NP model, we analyze the left-right symmetric models, taking into account current phenomenological bounds on the right-handed W{sub R}-boson mass and the left-right mixing parameter {zeta}.

Ali, A.; Borisov, A. V.; Zhuridov, D. V. [Deutsches Elektronen-Synchrotron, DESY, 22607 Hamburg (Germany); Faculty of Physics, Moscow State University, 119991 Moscow (Russian Federation)

2007-11-01T23:59:59.000Z

179

Method of separating short half-life radionuclides from a mixture of radionuclides  

DOE Patents [OSTI]

The present invention is a method of removing an impurity of plutonium, lead or a combination thereof from a mixture of radionuclides that contains the impurity and at least one parent radionuclide. The method has the steps of (a) insuring that the mixture is a hydrochloric acid mixture; (b) oxidizing the acidic mixture and specifically oxidizing the impurity to its highest oxidation state; and (c) passing the oxidized mixture through a chloride form anion exchange column whereupon the oxidized impurity absorbs to the chloride form anion exchange column and the {sup 229}Th or {sup 227}Ac ``cow`` radionuclide passes through the chloride form anion exchange column. The plutonium is removed for the purpose of obtaining other alpha emitting radionuclides in a highly purified form suitable for medical therapy. In addition to plutonium, lead, iron, cobalt, copper, uranium, and other metallic cations that form chloride anionic complexes that may be present in the mixture are removed from the mixture on the chloride form anion exchange column. 8 figs.

Bray, L.A.; Ryan, J.L.

1999-03-23T23:59:59.000Z

180

Prolonged lipoprotein half-life: effect on oxidative stability and physical features of lipoprotein particles  

E-Print Network [OSTI]

Atherosclerotic cardiovascular disease (ASCVD) is responsible for two out of the three leading causes of death in the United States. Oxidatively modified apolipoprotein B-containing lipoprotein (apoB-LPs) are known to contribute to atherosclerotic...

Simeral, Stephanie Bianco

2002-01-01T23:59:59.000Z

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


181

Methods of separating short half-life radionuclides from a mixture of radionuclides  

DOE Patents [OSTI]

The present invention is a method of obtaining a radionuclide product selected from the group consisting of .sup.223 Ra and .sup.225 Ac, from a radionuclide "cow" of .sup.227 Ac or .sup.229 Th respectively. The method comprises the steps of a) permitting ingrowth of at least one radionuclide daughter from said radionuclide "cow" forming an ingrown mixture; b) insuring that the ingrown mixture is a nitric acid ingrown mixture; c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the "cow" from at least one radionuclide daughter; d) insuring that the at least one radionuclide daughter contains the radionuclide product; e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and f) recycling the at least one radionuclide daughter by adding it to the "cow". In one embodiment the radionuclide "cow" is the .sup.227 Ac, the at least one daughter radionuclide is a .sup.227 Th and the product radionuclide is the .sup.223 Ra and the first nitrate form ion exchange column passes the .sup.227 Ac and retains the .sup.227 Th. In another embodiment the radionuclide "cow"is the .sup.229 Th, the at least one daughter radionuclide is a .sup.225 Ra and said product radionuclide is the .sup.225 Ac and the .sup.225 Ac and nitrate form ion exchange column retains the .sup.229 Th and passes the .sup.225 Ra/Ac.

Bray, Lane A. (Richland, WA); Ryan, Jack L. (West Richland, WA)

1998-01-01T23:59:59.000Z

182

Methods of separating short half-life radionuclides from a mixture of radionuclides  

DOE Patents [OSTI]

The present invention is a method of obtaining a radionuclide product selected from the group consisting of {sup 223}Ra and {sup 225}Ac, from a radionuclide ``cow`` of {sup 227}Ac or {sup 229}Th respectively. The method comprises the steps of (a) permitting ingrowth of at least one radionuclide daughter from said radionuclide ``cow`` forming an ingrown mixture; (b) insuring that the ingrown mixture is a nitric acid ingrown mixture; (c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the ``cow`` from at least one radionuclide daughter; (d) insuring that the at least one radionuclide daughter contains the radionuclide product; (e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and (f) recycling the at least one radionuclide daughter by adding it to the ``cow``. In one embodiment the radionuclide ``cow`` is the {sup 227}Ac, the at least one daughter radionuclide is a {sup 227}Th and the product radionuclide is the {sup 223}Ra and the first nitrate form ion exchange column passes the {sup 227}Ac and retains the {sup 227}Th. In another embodiment the radionuclide ``cow`` is the {sup 229}Th, the at least one daughter radionuclide is a {sup 225}Ra and said product radionuclide is the {sup 225}Ac and the {sup 225}Ac and nitrate form ion exchange column retains the {sup 229}Th and passes the {sup 225}Ra/Ac. 8 figs.

Bray, L.A.; Ryan, J.L.

1998-09-15T23:59:59.000Z

183

Precise half-life measurement of the superallowed beta(+) emitter (38)K(m)  

E-Print Network [OSTI]

of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6 J. C. Hardy and V. E. Iacob Cyclotron Institute at Texas A&M University, College Station, Texas 77843, USA J. R. Leslie and H.-B. Mak Department of Physics, Queen?s University...

Ball, G. C.; Boisvert, G.; Bricault, P.; Churchman, R.; Dombsky, M.; Lindner, T.; Macdonald, J. A.; Vandervoort, E.; Bishop, S.; D'Auria, J. M.; Hardy, John C.; Iacob, V. E.; Leslie, J. R.; Mak, H. -B.

2010-01-01T23:59:59.000Z

184

Leptonic B Decays at BaBar  

SciTech Connect (OSTI)

The authors will present the most recent results on leptonic B decays B{sup {+-}(0)} {yields} K*{sup {+-}(0)} {nu}{bar {nu}} and B{sup {+-}} {yields} {mu}{sup {+-}}{nu}, based on the data collected by the BaBar detector at PEP-II, an asymmetric e{sup +}e{sup -} collider at the center of mass energy of the {Upsilon}(4S) resonance. Rare B decays have always been a standard probe for New Physics (NP) searches. The very low Standard Model (SM) rate of these decays often make them unaccessible with the present experimental datasets, unless NP effects enhance the rate up to the current experimental sensitivity. Moreover, as NP effects can modify the decay kinematic, particular attention must be payed in order to perform a model independent analysis. A B-Factory provides an unique environment where to investigate these processes. The high number of B{bar B} pairs produced by a B-Factory often allows to approach the needed experimental sensitivity. Moreover, the clean environment and the closed kinematic of the initial state enable to obtaining a very pure sample where to look for these decays.

Monorchio, Diego; /INFN, Naples /Naples U.

2011-09-13T23:59:59.000Z

185

WHY SEARCH FOR DOUBLE BETA DECAY?  

E-Print Network [OSTI]

the search for neutrinoless double beta decay may prove verySearching for neutrinoless double beta decay is the onlysensitivity of neutrinoless double beta decay. The potential

Kayser, B.

2010-01-01T23:59:59.000Z

186

A search for two body muon decay signals  

E-Print Network [OSTI]

Lepton family number violation is tested by searching for $\\mu^+\\to e^+X^0$ decays among the 5.8$\\times 10^8$ positive muon decay events analyzed by the TWIST collaboration. Limits are set on the production of both massless and massive $X^0$ bosons. The large angular acceptance of this experiment allows limits to be placed on anisotropic $\\mu^+\\to e^+X^0$ decays, which can arise from interactions violating both lepton flavor and parity conservation. Branching ratio limits of order $10^{-5}$ are obtained for bosons with masses of 13 - 80 MeV/c$^2$ and with different decay asymmetries. For bosons with masses less than 13 MeV/c$^{2}$ the asymmetry dependence is much stronger and the 90% limit on the branching ratio varies up to $5.8 \\times 10^{-5}$. This is the first study that explicitly evaluates the limits for anisotropic two body muon decays.

R. Bayes; J. Bueno; Yu. I. Davydov; P. Depommier; W. Faszer; M. C. Fujiwara; C. A. Gagliardi; A. Gaponenko; D. R. Gill; A. Grossheim; P. Gumplinger; M. D. Hasinoff; R. S. Henderson; A. Hillairet; J. Hu; D. D. Koetke; R. P. MacDonald; G. M. Marshall; E. L. Mathie; R. E. Mischke; K. Olchanski; A. Olin; R. Openshaw; J. -M. Poutissou; R. Poutissou; V. Selivanov; G. Sheffer; B. Shin; T. D. S. Stanislaus; R. Tacik; R. E. Tribble

2015-03-10T23:59:59.000Z

187

Neutrinoless double beta decay  

E-Print Network [OSTI]

The status of the search for neutrinoless double beta decay is reviewed. The effort to reach the sensitivity needed to cover the effective Majorana neutrino mass corresponding to the degenerate and inverted mass hierarchy is described. Various issues concerning the theory (and phenomenology) of the relation between the $0\

Petr Vogel

2006-11-17T23:59:59.000Z

188

Vacuum Energy Decay  

E-Print Network [OSTI]

The problem of the vacuum energy decay is studied through the analysis of the vacuum survival amplitude ${\\mathcal A}(z, z')$. Transition amplitudes are computed for finite time-span, $Z\\equiv z^\\prime-z$, and their {\\em late time} behavior is discussed up to first order in the coupling constant, $\\l$.

Enrique Álvarez; Roberto Vidal

2011-11-09T23:59:59.000Z

189

Cosmology with decaying particles  

SciTech Connect (OSTI)

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.

Turner, M.S.

1984-09-01T23:59:59.000Z

190

Neutrinoless Double Beta Decay and its "Inverse"  

E-Print Network [OSTI]

Recent considerations by these authors pointed out the attractive features which a search for the exchange of heavy Majorana neutrinos could have for solving the mass and the lepton number puzzles for all neutrinos, in TeV-level electron-electron scattering. In the present note, we show that, contrary to subsequently published arguments, non-observation of neutrinoless double beta decay has, to date, no bearing on the promise of this important task for future linear electron colliders.

Clemens A. Heusch; Peter Minkowski

1996-11-18T23:59:59.000Z

191

Majorons Without Majorana Masses and Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

We explain excess events near the endpoints of the double beta decay spectra of several elements, using the neutrinoless emission of massless Goldstone bosons. Models with scalars carrying lepton number $-2$ are proposed for this purpose so that ordinary neutrinoless double beta decay is forbidden, and we can raise the scale of global symmetry breaking above the 10 keV scale needed for observable emission of conventional Majorons in double beta decay. The electron spectrum has a different shape, and the rate depends on different nuclear matrix elements, than for the emission of ordinary Majorons.

C. P. Burgess; J. M. Cline

1992-09-30T23:59:59.000Z

192

Decay of swirl in turbulent two phase flow  

E-Print Network [OSTI]

decrease in Reynolds number. Also, it was found that within experimental accuracy the decay was independent of initial swirl intensity. Their theoretical analysis of swirl decay characteristics in turbulent flow and the experiments conducted were... concentrations of the Polyox were put into the water in a uniform procedure in order to obtain consist. ent results. A venturi mixer was designed and used to di perse the polymer particles into the water in the mixing tank. The vigorous stir- ring bv the jet...

Neeley, Patrick Foster

2012-06-07T23:59:59.000Z

193

Determination of the X(3872) Meson Quantum Numbers  

E-Print Network [OSTI]

The quantum numbers of the X(3872) meson are determined to be J[superscript PC]=1[superscript ++] based on angular correlations in B[superscript +]?X(3872)K[superscript +] decays, where X(3872)??[superscript +]?[superscript ...

Williams, Michael

194

Double Beta Decay Experiments  

SciTech Connect (OSTI)

At present, neutrinoless double beta decay is perhaps the only experiment that can tell us whether the neutrino is a Dirac or a Majorana particle. Given the significance of the 0{nu}{beta}{beta}, there is a widespread interest for these rare event studies employing a variety of novel techniques. This paper describes the current status of DBD experiments. The Indian effort for an underground NDBD experiment at the upcoming INO laboratory is also presented.

Nanal, Vandana [Dept. of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Mumbai 400 005 (India)

2011-11-23T23:59:59.000Z

195

A Search for Neutrinoless Double-beta Decay of Germanium-76 J.F. Wilkerson1, 2, 3  

E-Print Network [OSTI]

A Search for Neutrinoless Double-beta Decay of Germanium-76 J.F. Wilkerson1, 2, 3 and S.R. Elliott4, The Majorana collaboration[1] is searching for neutrinoless double beta decay using 76 Ge, which has previously of neutrinoless double-beta decay would show that lepton number is violated, neutrinos are Majorana particles

196

Universal decay rule for reduced widths  

SciTech Connect (OSTI)

Emission processes including {alpha} decay, heavy cluster decay, and proton and di-proton emission are analyzed in terms of the well-known factorization between the penetrability and the reduced width. By using a shifted harmonic oscillator plus Coulomb cluster-daughter interaction it is possible to derive a linear relation between the logarithm of the reduced width squared and the fragmentation potential, defined as the difference between the Coulomb barrier and the Q value. This relation is fulfilled with a good accuracy for transitions between ground states, as well as for most {alpha} decays to low-lying 2{sup +} excited states. The well-known Viola-Seaborg rule, connecting half-lives with the Coulomb parameter and the product between fragment charge numbers, as well as the Blendowske scaling rule, connecting the spectroscopic factor with the mass number of the emitted cluster, can be easily understood in terms of the fragmentation potential. It is shown that the recently evidenced two regions in the dependence of reduced proton half-lives versus the Coulomb parameter are directly connected with the corresponding regions of the fragmentation potential.

Delion, D. S. [Horia Hulubei National Institute of Physics and Nuclear Engineering, 407 Atomistilor, Bucharest-Magurele 077125 (Romania) and Academy of Romanian Scientists, 54 Splaiul Independentei, Bucharest 050094 (Romania)

2009-08-15T23:59:59.000Z

197

A few-group delayed neutron model based on a consistent set of decay constants  

SciTech Connect (OSTI)

As part of an international effort, the Los Alamos National Laboratory has been asked to (1) determine if there is a set of dominant precursors that are common to all fissionable isotopes and all incident neutron energies, (2) expand the existing experimentally-measured few-group models commonly used in the nuclear industry into their 8-group equivalent using a consistent set of decay constants corresponding to these dominant precursors, and (3) formulate new group spectra for the equivalent 8-group model. In response to this request, LANL has calculated the theoretical delayed neutron yield for 14 different isotopes using three different incident neutron spectra (i.e., thermal, fast, and 14.1 MeV) using the current fission-yield and emission probability data found in ENDF-VI. An example of these results is shown in a figure in which the theoretical delayed neutron yields for the 271 precursors produced during thermal fission of {sup 235}U are plotted against the half-lives of the precursors. By comparing the results of all 14 isotopes, a preliminary set of precursors has been identified that are dominant within the various half-life regimes of the delayed neutron precursors. Also plotted on a figure are the group yields of the 8-group equivalent model of Keepin`s 6-group model. And finally, an example of the delayed neutron spectra for group 7 in the 8-group equivalent model is shown. A final report summarizing all results is expected to be released for review by the international steering committee by the summer of 1998.

Campbell, J.M.; Spriggs, G.D.

1998-01-22T23:59:59.000Z

198

Rare B Decays  

SciTech Connect (OSTI)

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

Jackson, P.D.; /Victoria U.

2006-02-24T23:59:59.000Z

199

Dark decay of Top quark  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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 ? 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. We discuss the implications for the Large Hadron Collider experiments including the analysis based on the lepton-jets.

Kong, Kyoungchui [Kansas; Lee, Hye-Sung [W&M, JLAB; Park, Myeonhun [Tokyo

2014-04-01T23:59:59.000Z

200

Introduction to Double Beta Decay  

SciTech Connect (OSTI)

While the neutrino oscillation experiments have measured non-zero square mass differences between neutrino flavors, the double beta decay is the most sensitive process to the absolute mass of the neutrinos and the only that can distinguish whether neutrino is a Dirac or a Majorana particle. These are a few but not the only reasons that many efforts, both theoretically and experimentally, are dedicated to the study of this process. In this lecture I'll give a short introduction to the double beta decay process. Different decay modes and mechanisms, a short history, decay rates and extraction of the neutrino mass parameter are presented.

Stoica, Sabin [Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O. Box MG-6, 077125 Magurele (Romania); Horia Hulubei Foundation, 407, Atomistilor street, 077125 Magurele (Romania)

2010-11-24T23:59:59.000Z

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


201

Experimental searches of neutrinoless double beta decay  

E-Print Network [OSTI]

Neutrinoless double decay is a unique probe for lepton number conservation and neutrino properties. It allows to investigate the Dirac/Majorana nature of the neutrinos and their absolute mass scale (hierarchy problem) with unprecedented sensitivity. A number of experiments are presently under preparation to cover the quasi-degenerate region of the neutrino mass spectrum. Improved sensitivities are however required to sound the so-called inverted hierarchy region. This is a real challenge faced by a number of new proposed projects, based either on large expansions of the present experiments or on new ideas top improve the technical performance or reduce the background contributions. A review of the most relevant ongoing experiments is given. The most relevant parameters contributing to the experimental sensitivity are discussed and a critical comparison of the future projects is proposed.

Oliviero Cremonesi

2012-12-19T23:59:59.000Z

202

Formation of $??$ atoms in $K_{?4} decay  

E-Print Network [OSTI]

We derive the decay rate of $\\pi\\mu$ atom formation in $K_{\\mu 4}$ decay. Using the obtained expressions we calculate the decay rate of atom formation and point out that considered decay can give a noticeable contribution as a background to the fundamental decay $K^+\\to \\pi^+\

S. R. Gevorkyan; A. V. Tarasov; O. O. Voskresenskaya

2009-12-01T23:59:59.000Z

203

VOLUME 85, NUMBER 14 P H Y S I C A L R E V I E W L E T T E R S 2 OCTOBER 2000 Spectroscopy of Double-Beta and Inverse-Beta Decays from 100Mo for Neutrinos  

E-Print Network [OSTI]

-time spectroscopic studies of low energy solar n are important for studies of the solar-n problems [17 for investigating both the Majorana n mass by neutrinoless double b decay 0nbb and low energy solar n's by inverse b for low energy solar n's, make it possible to detect, in real time, individual low energy solar n

Washington at Seattle, University of

204

Rare b hadron decays at the LHC  

E-Print Network [OSTI]

With the completion of Run~I of the CERN Large Hadron Collider, particle physics has entered a new era. The production of unprecedented numbers of heavy-flavoured hadrons in high energy proton-proton collisions allows detailed studies of flavour-changing processes. The increasingly precise measurements allow to probe the Standard Model with a new level of accuracy. Rare $b$ hadron decays provide some of the most promising approaches for such tests, since there are several observables which can be cleanly interpreted from a theoretical viewpoint. In this article, the status and prospects in this field are reviewed, with a focus on precision measurements and null tests.

Blake, T; Hiller, G

2015-01-01T23:59:59.000Z

205

$?$ Meson In $J/?$ Decays  

E-Print Network [OSTI]

Recently BES at BEPC found evidence for the existence of the $\\sigma$ meson in the process of $J/\\Psi \\to \\sigma\\omega \\to\\pi\\pi\\omega$. In this paper we firstly discuss the relevant coupling $g_{\\sigma\\pi\\pi}$ and show that the linear $\\sigma$ model gives rise to a reasonable description of the $\\sigma$ decay into $\\pi$'s, then we calculate the coupling constant $g^{th}_{J/\\Psi\\sigma\\omega}$ by using the perturbative QCD technique and the light-cone wave functions of the $\\sigma$ and $\\omega$ mesons. The results show that the theoretical value of $g^{th}_{J/\\Psi\\sigma\\omega}$ is within the range of experimental value $g_{J/\\Psi\\sigma\\omega}$.

Wujun Huo; Xinmin Zhang; Tao Huang

2002-03-20T23:59:59.000Z

206

Generator Coordinate Method framework for Double Beta Decay  

E-Print Network [OSTI]

We propose a consistent prescription for the derivation of the particle number and angular momentum projected QRPA (PQRPA) equation in the Generator Coordinate Method (GCM) framework for calculation of NME's of double-beta decay of axially deformed nuclei. We derive closed formulae for the calculation of excitation energies and wave functions of the intermediate nucleus.

Andrzej Bobyk; Wies?aw A. Kami?ski

2014-11-10T23:59:59.000Z

207

Systematic decomposition of the neutrinoless double beta decay operator  

E-Print Network [OSTI]

We discuss the systematic decomposition of the dimension nine neutrinoless double beta decay operator, focusing on mechanisms with potentially small contributions to neutrino mass, while being accessible at the LHC. We first provide a (d=9 tree-level) complete list of diagrams for neutrinoless double beta decay. From this list one can easily recover all previously discussed contributions to the neutrinoless double beta decay process, such as the celebrated mass mechanism or "exotics", such as contributions from left-right symmetric models, R-parity violating supersymmetry and leptoquarks. More interestingly, however, we identify a number of new possibilities which have not been discussed in the literature previously. Contact to earlier works based on a general Lorentz-invariant parametrisation of the neutrinoless double beta decay rate is made, which allows, in principle, to derive limits on all possible contributions. We furthermore discuss possible signals at the LHC for mediators leading to the short-range part of the amplitude with one specific example. The study of such contributions would gain particular importance if there were a tension between different measurements of neutrino mass such as coming from neutrinoless double beta decay and cosmology or single beta decay.

Florian Bonnet; Martin Hirsch; Toshihiko Ota; Walter Winter

2014-06-23T23:59:59.000Z

208

Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism  

E-Print Network [OSTI]

In the minimal supersymmetric extension to the Standard Model, a non-zero lepton number violating coupling lambda'_111 predicts both neutrinoless double beta decay and resonant single slepton production at the LHC. We show that, in this case, if neutrinoless double beta decay is discovered in the next generation of experiments, there exist good prospects to observe single slepton production at the LHC. Neutrinoless double beta decay could otherwise result from a different source (such as a non-zero Majorana neutrino mass). Resonant single slepton production at the LHC can therefore discriminate between the lambda'_111 neutrinoless double beta decay mechanism and others.

B. C. Allanach; C. H. Kom; H. Päs

2009-02-26T23:59:59.000Z

209

LHC and B physics probes of neutrinoless double beta decay in supersymmetry without R-parity  

E-Print Network [OSTI]

In the event of an observation of neutrinoless double beta decay, a relevant question would be: what lepton number violating physics is responsible for the decay? The exchange of Majorana neutrinos and/or supersymmetric particles may contribute. We point out that measurements of supersymmetric signals at the LHC, including single slepton production, could be used to help bound some supersymmetric processes contributing to neutrinoless double beta decay. LHC information about the supersymmetric spectrum could be combined with Bd-Bd bar mixing data in order to bound a competing neutrinoless double beta decay process involving sbottom exchange.

B. C. Allanach; C. H. Kom; H. Päs

2009-07-24T23:59:59.000Z

210

Large Hadron Collider Probe of Supersymmetric Neutrinoless Double-Beta-Decay Mechanism  

SciTech Connect (OSTI)

In the minimal supersymmetric extension to the standard model, a nonzero lepton number violating coupling {lambda}{sub 111}{sup '} predicts both neutrinoless double-beta-decay and resonant single slepton production at the LHC. We show that, in this case, if neutrinoless double beta decay is discovered in the next generation of experiments, there exist good prospects to observe single slepton production at the LHC. Neutrinoless double beta decay could otherwise result from a different source (such as a nonzero Majorana neutrino mass). Resonant single slepton production at the LHC can therefore discriminate between the {lambda}{sub 111}{sup '} neutrinoless double-beta-decay mechanism and others.

Allanach, B. C.; Kom, C. H.; Paes, H. [DAMTP, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom); Cavendish Laboratory, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Fakultaet fuer Physik, Technische Universitaet Dortmund, D-44221, Dortmund (Germany)

2009-08-28T23:59:59.000Z

211

Limits on flavor changing neutral currents in D-0 meson Decays  

E-Print Network [OSTI]

Using the CLEO II detector at the Cornell Electron Storage Ring, we have searched for flavor changing neutral currents and lepton family number violations in D-0 meson decays. The upper limits on the branching fractions ...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Copty, N.; Davis, Robin E. P.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan

1996-04-01T23:59:59.000Z

212

Beta decay rates for nuclei with 115 < A < 140 for r-process nucleosynthesis  

E-Print Network [OSTI]

For r-process nucleosynthesis the beta decay rates for a number of neutron-rich intermediate heavy nuclei are calculated. The model for the beta strength function is able to reproduce the observed half~lives quite well.

Kamales Kar; Soumya Chakravarti; V. R. Manfredi

2006-03-19T23:59:59.000Z

213

Wave Decay in MHD Turbulence  

E-Print Network [OSTI]

We present a model for nonlinear decay of the weak wave in three-dimensional incompressible magnetohydrodynamic (MHD) turbulence. We show that the decay rate is different for parallel and perpendicular waves. We provide a general formula for arbitrarily directed waves and discuss particular limiting cases known in the literature. We test our predictions with direct numerical simulations of wave decay in three-dimensional MHD turbulence, and discuss the influence of turbulent damping on the development of linear instabilities in the interstellar medium and on other important astrophysical processes.

Andrey Beresnyak; Alex Lazarian

2008-05-06T23:59:59.000Z

214

Neutrinoless Double Beta Decay Constraints  

E-Print Network [OSTI]

A brief overview is given of theoretical analyses with neutrinoless double beta decay experiments. Theoretical bounds on the ``observable'', _betabeta, are presented. By using experimental bounds on _betabeta, allowed regions are obtained on the m_l-cos{2theta_12} plane, where m_l stands for the lightest neutrino mass. It is shown that Majorana neutrinos can be excluded by combining possible results of future neutrinoless double beta decay and {}^3H beta decay experiments. A possibility to constrain one of two Majorana phases is discussed also.

Hiroaki Sugiyama

2003-07-25T23:59:59.000Z

215

Synthesis of a new element with atomic number Z=117  

SciTech Connect (OSTI)

The discovery of a new chemical element with atomic number Z=117 is reported. The isotopes 293117 and 294117 were produced in fusion reactions between 48Ca and 249Bk. Decay chains involving eleven new nuclei were identified by means of the Dubna Gas Filled Recoil Separator. The measured decay properties show a strong rise of stability for heavier isotopes with Z111, validating the concept of the long sought island of enhanced stability for super-heavy nuclei.

Oganessian, Yuri Ts. [FLNR-JINR, Russia; Abdullin, F. Sh. [Joint Institute for Nuclear Research, Dubna, Russia; Bailey, P. D. [Oak Ridge National Laboratory (ORNL); Benker, D. E. [Oak Ridge National Laboratory (ORNL); Bennett, M. E. [University of Nevada, Las Vegas; Dmitriev, S. [FLNR-JINR, Russia; Ezold, Julie G. [Oak Ridge National Laboratory (ORNL); Hamilton, J. H. [Vanderbilt University; Henderson, R. [Lawrence Livermore National Laboratory (LLNL); Itkis, M. G. [FLNR-JINR, Russia; Lobanov, Yu. V. [Joint Institute for Nuclear Research, Dubna, Russia; Mezentsev, A. N. [Joint Institute for Nuclear Research, Dubna, Russia; Moody, K. [Lawrence Livermore National Laboratory (LLNL); Nelson, S. L. [Lawrence Livermore National Laboratory (LLNL); Polyakov, A. N. [Joint Institute for Nuclear Research, Dubna, Russia; Porter, C. E. [Oak Ridge National Laboratory (ORNL); Ramayya, A. V. [Vanderbilt University; Riley, F. D. [Oak Ridge National Laboratory (ORNL); Roberto, James B [ORNL; Ryabinin, M. A. [Research Institute of Atomic Reactors, Dimitrovgrad, Russia; Rykaczewski, Krzysztof Piotr [ORNL; Sagaidak, R. N. [Joint Institute for Nuclear Research, Dubna, Russia; Shaughnessy, D. [Lawrence Livermore National Laboratory (LLNL); Shirokovsky, I. V. [Joint Institute for Nuclear Research, Dubna, Russia; Stoyer, M. [Lawrence Livermore National Laboratory (LLNL); Subbotin, V. G. [Joint Institute for Nuclear Research, Dubna, Russia; Sudowe, R. [University of Nevada, Las Vegas; Sukhov, A. M. [Joint Institute for Nuclear Research, Dubna, Russia; Tsyganov, Yu. S. [Joint Institute for Nuclear Research, Dubna, Russia; Utyonkov, V. [FLNR-JINR, Russia; Voinov, A. A. [Joint Institute for Nuclear Research, Dubna, Russia; Vostokin, G. K. [Joint Institute for Nuclear Research, Dubna, Russia; Wilk, P. A. [Lawrence Livermore National Laboratory (LLNL)

2010-01-01T23:59:59.000Z

216

Radiative Leptonic B Decays  

SciTech Connect (OSTI)

We present the results of a search for B{sup +} meson decays into {gamma}{ell}{sup +}{nu}{sub {ell}}, where {ell} = e,{mu}. We use a sample of 232 million B{bar B} meson pairs recorded at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B factory. We measure a partial branching fraction {Delta}{beta} 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 {Upsilon}(4S) center-of-mass frame. We find {Delta}{Beta}(B{sup +} {yields} {gamma}{ell}{sup +}{nu}{sub {ell}}) = (-0.3{sub 1.5}{sup +1.3}(statistical){sub -0.6}{sup +0.6}(systematic) {+-} 0.1(theoretical)) x 10{sup -6}, under the assumption of lepton universality. Interpreted as a 90% confidence-level Bayesian upper limit, the result corresponds to 1.7 x 10{sup -6} for a prior at in amplitude, and 2.3 x 10{sup -6} for a prior at in branching fraction.

Chen, Edward Tann; /Caltech; ,

2008-10-06T23:59:59.000Z

217

Computer code for double beta decay QRPA based calculations  

E-Print Network [OSTI]

. The Enriched Xenon Observatory for neutrinoless double beta decay (EXO) will search for the rare decays

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

218

The decay of hot nuclei  

SciTech Connect (OSTI)

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

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

1988-11-01T23:59:59.000Z

219

Neutrinoless Double Beta-Decay  

E-Print Network [OSTI]

The neutrinoless double $\\beta$-decay of nuclei is reviewed. We discuss neutrino mixing and 3x3 PMNS neutrino mixing matrix. Basic theory of neutrinoless double $\\beta$-decay is presented in some details. Results of different calculations of nuclear matrix element are discussed. Experimental situation is considered. The Appendix is dedicated to E. Majorana (brief biography and his paper in which the theory of Majorana particles is given)

S. M. Bilenky

2010-01-12T23:59:59.000Z

220

Beta and gamma decays April 9, 2002  

E-Print Network [OSTI]

Beta and gamma decays April 9, 2002 1 Simple Fermi theory of beta decay ² Beta decay is one by the emission of a positive or negative beta particle (positron or electron). To ensure conservation of lepton emitted in beta decay is a continuum of energies, up to a maximum value, with most emitted betas having

Landstreet, John D.

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


221

Decay experiments to test beta - and gamma -strength functions  

E-Print Network [OSTI]

The decays of six delayed-proton precursors have been studied with the particle-X-ray coincidence technique, yielding a more or less detailed view of level widths in the proton emitting nuclei. The results lead to a reevaluation of the techniques for calculating level densities and average gamma-decay widths in exotic nuclei. With these aspects of beta -delayed proton decay specified, the proton energy spectra of a number of precursors (65

Hardy, J C

1981-01-01T23:59:59.000Z

222

Circumscribing late dark matter decays model-independently  

SciTech Connect (OSTI)

A number of theories, spanning a wide range of mass scales, predict dark matter candidates that have lifetimes much longer than the age of the Universe, yet may produce a significant flux of gamma rays in their decays today. We constrain such late-decaying dark matter scenarios model-independently by utilizing gamma-ray line emission limits from the Galactic Center region obtained with the SPI spectrometer on INTEGRAL, and the determination of the isotropic diffuse photon background by SPI, COMPTEL, and EGRET observations. We show that no more than {approx}5% of the unexplained MeV background can be produced by late dark matter decays either in the Galactic halo or cosmological sources.

Yueksel, Hasan; Kistler, Matthew D. [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States) and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, Ohio 43210 (United States)

2008-07-15T23:59:59.000Z

223

Experimental charmonium decay results from BES  

E-Print Network [OSTI]

Based on 14 million psi(2S) and 58 million J/psi events collected by the BESII detector, the leptonic decay of psi(2S) into $\\tau^+\\tau^-$, psi(2S) multi-body decays, chi_cJ decays, and J/psi hadronic decays are studied, and the branching fractions of these decays are reported. These results may shed light on the understanding of QCD.

Ping Rong-Gang; F. A. Harris; for BES collaboration

2007-11-23T23:59:59.000Z

224

Signature of nonexponential nuclear decay  

E-Print Network [OSTI]

Precision tests of decay law of radioactive nuclei have not so far found any deviation from the exponential decay law at early time, as predicted by quantum mechanics. In this paper, we show that the quantum decoherence time (i.e. the timescale of nonexponential decay) of the quasifission or fission process should be of the order of attosecond considering the atom of the fissioning nucleus as a quantum detector. Hence, the observed decay timescale of the quasifission or fission process of even highly excited (EX greater than 50 MeV) transuranium and uraniumlike complexes should be rather long (of the order of attosecond) in spite of their very fast exponential decay timescale (of the order of zeptosecond) as measured by the nuclear techniques. Recent controversy regarding the observation of very long (of the order of attosecond ) and very short (of the order of zeptosecond ) quasifission or fission timescales for similar systems at similar excitation energies as obtained by direct techniques (crystal blocking...

Ray, A; De, A

2015-01-01T23:59:59.000Z

225

{alpha}-decay spectroscopy of deformed nuclei reexamined  

SciTech Connect (OSTI)

We perform an extensive analysis of {alpha}-decays to 2{sup +} and 4{sup +} states in deformed even-even nuclei by using the stationary coupled channels approach. Collective excitations are described within the rigid rotor model. The {alpha}-nucleus interaction is given by a double folding procedure with M3Y plus Coulomb nucleon-nucleon forces. We use a repulsive potential with one independent parameter in order to localize the {alpha}-particle on the nuclear surface and to fit the experimental Q-value. The decaying state is identified with the first resonance inside the resulting pocket-like potential, as suggested by microscopic calculations. We obtain a good agreement with existing experimental data concerning decay widths to J=2{sup +},4{sup +} states. The total {alpha}-decay half-lives agrees very well with experimental values by fitting the spectroscopic factor in terms of charge and neutron numbers separately for Z<82 and Z>82. We give predictions for intensities and hindrance factors for 52 even-even {alpha}-emitters with {beta}{sub 2}>0.15 and E{sub 2{sup +}}<200 kev. Comparison between the phenomenological and microscopic spectroscopic factors revealed large {alpha}-clustering components for nuclei close and above N=82,Z=82,N=126 magic numbers.

Peltonen, S.; Suhonen, J. [Department of Physics, University of Jyvaeskylae, POB 35, FIN-40351, Jyvaeskylae (Finland); Delion, D. S. [National Institute of Physics and Nuclear Engineering, Atomistilor 407, Bucharest-Magurele, 077125 (Romania); Academy of Romanian Scientists, 54 Splaiul Independentei, Bucharest, 050085 (Romania)

2008-09-15T23:59:59.000Z

226

Neutrino masses and Neutrinoless Double Beta Decay: Status and expectations  

E-Print Network [OSTI]

Two most outstanding questions are puzzling the world of neutrino Physics: the possible Majorana nature of neutrinos and their absolute mass scale. Direct neutrino mass measurements and neutrinoless double beta decay (0nuDBD) are the present strategy to solve the puzzle. Neutrinoless double beta decay violates lepton number by two units and can occurr only if neutrinos are massive Majorana particles. A positive observation would therefore necessarily imply a new regime of physics beyond the standard model, providing fundamental information on the nature of the neutrinos and on their absolute mass scale. After the observation of neutrino oscillations and given the present knowledge of neutrino masses and mixing parameters, a possibility to observe 0nuDBDD at a neutrino mass scale in the range 10-50 meV could actually exist. This is a real challenge faced by a number of new proposed projects. Present status and future perpectives of neutrinoless double-beta decay experimental searches is reviewed. The most important parameters contributing to the experimental sensitivity are outlined. A short discussion on nuclear matrix element calculations is also given. Complementary measurements to assess the absolute neutrino mass scale (cosmology and single beta decays) are also discussed.

Oliviero Cremonesi

2010-02-07T23:59:59.000Z

227

Predicting Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

We give predictions for the neutrinoless double beta decay rate in a simple variant of the A_4 family symmetry model. We show that there is a lower bound for the neutrinoless double beta decay amplitude even in the case of normal hierarchical neutrino masses, corresponding to an effective mass parameter |m_{ee}| >= 0.17 \\sqrt{\\Delta m^2_{ATM}}. This result holds both for the CP conserving and CP violating cases. In the latter case we show explicitly that the lower bound on |m_{ee}| is sensitive to the value of the Majorana phase. We conclude therefore that in our scheme, neutrinoless double beta decay may be accessible to the next generation of high sensitivity experiments.

M. Hirsch; Ernest Ma; J. W. F. Valle; A. Villanova del Moral

2005-07-12T23:59:59.000Z

228

New Paradigm for Baryon and Lepton Number Violation  

E-Print Network [OSTI]

The possible discovery of proton decay, neutron-antineutron oscillation, neutrinoless beta decay in low energy experiments, and exotic signals related to the violation of the baryon and lepton numbers at collider experiments will change our understanding of the conservation of fundamental symmetries in nature. In this review we discuss the rare processes due to the existence of baryon and lepton number violating interactions. The simplest grand unified theories and the neutrino mass generation mechanisms are discussed. The theories where the baryon and lepton numbers are defined as local gauge symmetries spontaneously broken at the low scale are discussed in detail. The simplest supersymmetric gauge theory which predicts the existence of lepton number violating processes at the low scale is investigated. The main goal of this review is to discuss the main implications of baryon and lepton number violation in physics beyond the Standard Model.

Perez, Pavel Fileviez

2015-01-01T23:59:59.000Z

229

A,B,C`s of nuclear science  

SciTech Connect (OSTI)

This introductory level presentation contains information on nuclear structure, radioactivity, alpha decay, beta decay, gamma decay, half-life, nuclear reactions, fusion, fission, cosmic rays, and radiation protection. Nine experiments with procedures and test questions are included.

Noto, V.A. [Mandeville High School, LA (United States); Norman, E.B.; Chan, Yuen-Dat; Dairiki, J.; Matis, H.S.; McMahan, M.A.; Otto, R. [Lawrence Berkeley Lab., CA (United States)

1995-08-07T23:59:59.000Z

230

UNIVERSITE DE CAEN BASSE-NORMANDIE attribu par la bibliothque  

E-Print Network [OSTI]

of double beta decay and in particular the search for neutrinoless double beta decay (0). The quantityNEMO experiment aims to reach a sensitivity up to 10 26 years on the half-life of neutrinoless double beta decay

Paris-Sud XI, Université de

231

A Search for Neutrinoless Double Beta Decay of Te-130  

E-Print Network [OSTI]

far unobserved, neutrinoless double beta decay is a possibleright for the neutrinoless double beta decay of 130 Te. Thisprocess, with neutrinoless double beta decay being the most

Bryant, Adam Douglas

2010-01-01T23:59:59.000Z

232

What can we learn from neutrinoless double beta decay experiments?  

E-Print Network [OSTI]

Limits From Neutrinoless Double-Beta Decay (Rev. ),” ina next generation neutrinoless double beta decay search andPARTICLES? NO NEUTRINOLESS DOUBLE BETA DECAY AND INVERTED

Bahcall, John N.

2009-01-01T23:59:59.000Z

233

Searches for solar-influenced radioactive decay anomalies using Spacecraft RTGs  

E-Print Network [OSTI]

Experiments showing a seasonal variation of the nuclear decay rates of a number of different nuclei, and decay anomalies apparently related to solar flares and solar rotation, have suggested that the Sun may somehow be influencing nuclear decay processes. Recently, Cooper searched for such an effect in $^{238}$Pu nuclei contained in the radioisotope thermoelectric generators (RTGs) on board the Cassini spacecraft. In this paper we modify and extend Cooper's analysis to obtain constraints on anomalous decays of $^{238}$Pu over a wider range of models, but these limits cannot be applied to other nuclei if the anomaly is composition-dependent. We also show that it may require very high sensitivity for terrestrial experiments to discriminate among some models if such a decay anomaly exists, motivating the consideration of future spacecraft experiments which would require less precision.

Krause, D E; Fischbach, E; Buncher, J B; Ging, A; Jenkins, J H; Longuski, J M; Strange, N; Sturrock, P A

2012-01-01T23:59:59.000Z

234

Searches for solar-influenced radioactive decay anomalies using Spacecraft RTGs  

E-Print Network [OSTI]

Experiments showing a seasonal variation of the nuclear decay rates of a number of different nuclei, and decay anomalies apparently related to solar flares and solar rotation, have suggested that the Sun may somehow be influencing nuclear decay processes. Recently, Cooper searched for such an effect in $^{238}$Pu nuclei contained in the radioisotope thermoelectric generators (RTGs) on board the Cassini spacecraft. In this paper we modify and extend Cooper's analysis to obtain constraints on anomalous decays of $^{238}$Pu over a wider range of models, but these limits cannot be applied to other nuclei if the anomaly is composition-dependent. We also show that it may require very high sensitivity for terrestrial experiments to discriminate among some models if such a decay anomaly exists, motivating the consideration of future spacecraft experiments which would require less precision.

D. E. Krause; B. A. Rogers; E. Fischbach; J. B Buncher; A. Ging; J. H. Jenkins; J. M. Longuski; N. Strange; P. A. Sturrock

2012-05-31T23:59:59.000Z

235

Search for Rare and Forbidden Charm Meson Decays at Fermilab E791  

E-Print Network [OSTI]

We report the results of a blind search for flavor-changing neutral current, lepton-flavor violating, and lepton-number violating decays of D+, D(s)+, and D0 mesons (and their antiparticles) into modes containing muons and electrons. Using data from Fermilab charm hadroproduction experiment E791, we examine the pi l l and K l l decay modes of D+ and D(s)+ and the l+ l- decay modes of D0. No evidence for any of these decays is found. Therefore, we present branching-fraction upper limits at 90% confidence level for the 24 decay modes examined. Eight of these modes have no previously reported limits, and fourteen are reported with significant improvements over previously published results.

Fermilab E791 Collaboration; D. J. Summers

2000-10-01T23:59:59.000Z

236

Studies of the N=90 region: The decay of 154Eu to 154Gd  

SciTech Connect (OSTI)

The decay of {sup 154}Eu {yields} {sup 154}Gd has been studied by {gamma}-ray singles and {gamma}-{gamma} coincidence spectroscopy using an array of 20 Compton-suppressed Ge detectors. The primary goal of the work was to confirm or refute a large number of questionable features in the decay scheme: the outcome is the removal of 8 levels from the previously adopted scheme, with the result that a new type of collective band is revealed. Many weak decay branches for the decay are clarified. These results are critical for understanding the structure of {sup 154}Gd and the N = 90 isotones; and the improved completeness of the decay scheme contributes to the use of {sup 154}Eu as a metrological standard.

Kulp, W.D.; Wood, J.L.; Krane, K.S.; Loats, J.; Schmelzenbach, P.; Stapels, C.J.; Larimer, R.-M.; Norman, E.B.

2003-12-05T23:59:59.000Z

237

Hyper Space Complex Number  

E-Print Network [OSTI]

A new kind of numbers called Hyper Space Complex Numbers and its algebras are defined and proved. It is with good properties as the classic Complex Numbers, such as expressed in coordinates, triangular and exponent forms and following the associative and commutative laws of addition and multiplication. So the classic Complex Number is developed from in complex plane with two dimensions to in complex space with N dimensions and the number system is enlarged also.

Shanguang Tan

2007-04-23T23:59:59.000Z

238

Beta decay of Ga-62  

E-Print Network [OSTI]

from the ex- perimental ft value for a 01?01 b decay between analog states with the relation @3# 0556-2813/2003/68~1!/015501~6!/$20.00 68 015501- of 62Ga . Hardy, V. E. Mayes, R. G. Neilson, M. Sanchez-Vega, and R. E. Tribble y, College Station...

Hyman, BC; Iacob, VE; Azhari, A.; Gagliardi, Carl A.; Hardy, John C.; Mayes, VE; Neilson, RG; Sanchez-Vega, M.; Tang, X.; Trache, L.; Tribble, Robert E.

2003-01-01T23:59:59.000Z

239

Constraining neutrinoless double beta decay  

E-Print Network [OSTI]

A class of discrete flavor-symmetry-based models predicts constrained neutrino mass matrix schemes that lead to specific neutrino mass sum-rules (MSR). We show how these theories may constrain the absolute scale of neutrino mass, leading in most of the cases to a lower bound on the neutrinoless double beta decay effective amplitude.

L. Dorame; D. Meloni; S. Morisi; E. Peinado; J. W. F. Valle

2011-11-23T23:59:59.000Z

240

Neutrinoless double beta decay studied with configuration mixing methods  

E-Print Network [OSTI]

We study neutrinoless double beta decay of several isotopes with state-of-the-art beyond self-consistent mean field methods to compute the nuclear matrix elements (NME). Generating coordinate method with particle number and angular momentum projection (GCM+PNAMP) is used for finding mother and granddaughter states and evaluating transition operators between different nuclei. We analyze explicitly the role of the deformation, pairing and configuration mixing in the evaluation of the NME.

Tomas R. Rodriguez; Gabriel Martinez-Pinedo

2010-12-08T23:59:59.000Z

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


241

Search for the rare decays Bs -->mumu and Bd -->mumu  

E-Print Network [OSTI]

A search for the decays Bs-->mumu and Bd-->mumu is performed with about 37 pb^{-1} of pp collisions at sqrt{s} = 7 TeV collected by the LHCb experiment at the Large Hadron Collider at CERN. The observed numbers of events are consistent with the background expectations. The resulting upper limits on the branching ratios are BR(Bs-->mumu) mumu) <1.5 x 10^{-8} at 95% confidence level.

LHCb Collaboration; R. Aaij; B. Adeva; M. Adinolfi; C. Adrover; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; P. Alvarez Cartelle; A. A. Alves Jr; S. Amato; Y. Amhis; J. Amoraal; J. Anderson; R. B. Appleby; O. Aquines Gutierrez; L. Arrabito; M. Artuso; E. Aslanides; G. Auriemma; S. Bachmann; D. S. Bailey; V. Balagura; W. Baldini; R. J. Barlow; C. Barschel; S. Barsuk; A. Bates; C. Bauer; Th. Bauer; A. Bay; I. Bediaga; K. Belous; I. Belyaev; E. Ben-Haim; M. Benayoun; G. Bencivenni; R. Bernet; M. -O. Bettler; M. van Beuzekom; A. Bien; S. Bifani; A. Bizzeti; P. M. Bjřrnstad; T. Blake; F. Blanc; C. Blanks; J. Blouw; S. Blusk; A. Bobrov; V. Bocci; A. Bondar; N. Bondar; W. Bonivento; S. Borghi; A. Borgia; E. Bos; T. J. V. Bowcock; C. Bozzi; T. Brambach; J. van den Brand; J. Bressieux; S. Brisbane; M. Britsch; T. Britton; N. H. Brook; H. Brown; A. Büchler-Germann; A. Bursche; J. Buytaert; S. Cadeddu; J. M. Caicedo Carvajal; O. Callot; M. Calvi; M. Calvo Gomez; A. Camboni; P. Campana; A. Carbone; G. Carboni; R. Cardinale; A. Cardini; L. Carson; K. Carvalho Akiba; G. Casse; M. Cattaneo; M. Charles; Ph. Charpentier; N. Chiapolini; X. Cid Vidal; P. J. Clark; P. E. L. Clarke; M. Clemencic; H. V. Cliff; J. Closier; C. Coca; V. Coco; J. Cogan; P. Collins; F. Constantin; G. Conti; A. Contu; M. Coombes; G. Corti; G. A. Cowan; R. Currie; B. D'Almagne; C. D'Ambrosio; W. Da Silva; P. David; I. De Bonis; S. De Capua; M. De Cian; F. De Lorenzi; J. M. De Miranda; L. De Paula; P. De Simone; D. Decamp; H. Degaudenzi; M. Deissenroth; L. Del Buono; C. Deplano; O. Deschamps; F. Dettori; J. Dickens; H. Dijkstra; M. Dima; P. Diniz Batista; S. Donleavy; D. Dossett; A. Dovbnya; F. Dupertuis; R. Dzhelyadin; C. Eames; S. Easo; U. Egede; V. Egorychev; S. Eidelman; D. van Eijk; F. Eisele; S. Eisenhardt; L. Eklund; Ch. Elsasser; D. G. d'Enterria; D. Esperante Pereira; L. Estčve; A. Falabella; E. Fanchini; C. Färber; G. Fardell; C. Farinelli; S. Farry; V. Fave; V. Fernandez Albor; M. Ferro-Luzzi; S. Filippov; C. Fitzpatrick; F. Fontanelli; R. Forty; M. Frank; C. Frei; M. Frosini; S. Furcas; A. Gallas Torreira; D. Galli; M. Gandelman; P. Gandini; Y. Gao; J-C. Garnier; J. Garofoli; L. Garrido; C. Gaspar; N. Gauvin; M. Gersabeck; T. Gershon; Ph. Ghez; V. Gibson; V. V. Gligorov; C. Göbel; D. Golubkov; A. Golutvin; A. Gomes; H. Gordon; M. Grabalosa Gándara; R. Graciani Diaz; L. A. Granado Cardoso; E. Graugés; G. Graziani; A. Grecu; S. Gregson; B. Gui; E. Gushchin; Yu. Guz; T. Gys; G. Haefeli; S. C. Haines; T. Hampson; S. Hansmann-Menzemer; R. Harji; N. Harnew; P. F. Harrison; J. He; K. Hennessy; P. Henrard; J. A. Hernando Morata; E. van Herwijnen; A. Hicheur; E. Hicks; W. Hofmann; K. Holubyev; P. Hopchev; W. Hulsbergen; P. Hunt; T. Huse; R. S. Huston; D. Hutchcroft; V. Iakovenko; P. Ilten; J. Imong; R. Jacobsson; M. Jahjah Hussein; E. Jans; F. Jansen; P. Jaton; B. Jean-Marie; F. Jing; M. John; D. Johnson; C. R. Jones; B. Jost; F. Kapusta; T. M. Karbach; J. Keaveney; U. Kerzel; T. Ketel; A. Keune; B. Khanji; Y. M. Kim; M. Knecht; S. Koblitz; A. Konoplyannikov; P. Koppenburg; A. Kozlinskiy; L. Kravchuk; G. Krocker; P. Krokovny; F. Kruse; K. Kruzelecki; M. Kucharczyk; S. Kukulak; R. Kumar; T. Kvaratskheliya; V. N. La Thi; D. Lacarrere; G. Lafferty; A. Lai; R. W. Lambert; G. Lanfranchi; C. Langenbruch; T. Latham; R. Le Gac; J. van Leerdam; J. -P. Lees; R. Lefčvre; A. Leflat; J. Lefrançois; O. Leroy; T. Lesiak; L. Li; Y. Y. Li; L. Li Gioi; M. Lieng; M. Liles; R. Lindner; C. Linn; B. Liu; G. Liu; J. H. Lopes; E. Lopez Asamar; N. Lopez-March; J. Luisier; B. M'charek; F. Machefert; I. V. Machikhiliyan; F. Maciuc; O. Maev; J. Magnin; A. Maier; S. Malde; R. M. D. Mamunur; G. Manca; G. Mancinelli; N. Mangiafave; U. Marconi; R. Märki; J. Marks; G. Martellotti; A. Martens; L. Martin; A. Martín Sánchez; D. Martinez Santos; A. Massafferri; Z. Mathe; C. Matteuzzi; M. Matveev; V. Matveev; E. Maurice; B. Maynard; A. Mazurov; G. McGregor; R. McNulty; C. Mclean; M. Meissner; M. Merk; J. Merkel; M. Merkin; R. Messi; S. Miglioranzi; D. A. Milanes; M. -N. Minard; S. Monteil; D. Moran; P. Morawski; J. V. Morris; R. Mountain; I. Mous; F. Muheim; K. Müller; R. Muresan; F. Murtas; B. Muryn; M. Musy; J. Mylroie-Smith; P. Naik; T. Nakada; R. Nandakumar; J. Nardulli; M. Nedos; M. Needham; N. Neufeld; M. Nicol; S. Nies; V. Niess; N. Nikitin; A. Oblakowska-Mucha; V. Obraztsov; S. Oggero; O. Okhrimenko; R. Oldeman; M. Orlandea; A. Ostankov; B. Pal; J. Palacios; M. Palutan; J. Panman; A. Papanestis; M. Pappagallo; C. Parkes; C. J. Parkinson; G. Passaleva; G. D. Patel; M. Patel; S. K. Paterson; G. N. Patrick; C. Patrignani; C. Pavel -Nicorescu; A. Pazos Alvarez; A. Pellegrino; G. Penso; M. Pepe Altarelli; S. Perazzini; D. L. Perego; E. Perez Trigo; A. Pérez-Calero Yzquierdo; P. Perret; A. Petrella

2012-07-23T23:59:59.000Z

242

NEUTRINOLESS DOUBLE BETA DECAY AND ITS “INVERSE”  

E-Print Network [OSTI]

subsequently published arguments, non-observation of neutrinoless double beta decay has, to date, no bearing on

Clemens A. Heusch; Peter Minkowski

1996-01-01T23:59:59.000Z

243

Neutrinoless Double Beta Decay and CP Violation  

E-Print Network [OSTI]

neutrinoless double beta decay in the case of two neutrino generations (or when the third generation leptons do

Patrick J. O’donnell; Utpal Sarkar

1993-01-01T23:59:59.000Z

244

Light-Quark Decays in Heavy Hadrons  

E-Print Network [OSTI]

We consider weak decays of heavy hadrons (bottom and charmed) where the heavy quark acts as a spectator. Theses decays are heavily phase-space suppressed but may become experimentally accessible in the near future. These decays are interesting as a QCD laboratory to study the behaviour of the light quarks in the colour-background field of the heavy spectator.

Faller, Sven

2015-01-01T23:59:59.000Z

245

Double beta decay: experiments and theory review  

E-Print Network [OSTI]

Neutrinoless double beta decay is one of the most powerful tools to set the neutrino mass absolute scale and establish whether the neutrino is a Majorana particle. After a summary of the neutrinoless double beta decay phenomenology, the present status of the experimental search for this rare decay is reported and the prospects for next generation experiments are reviewed.

A. Nucciotti

2007-07-28T23:59:59.000Z

246

Imperfect World of $??$-decay Nuclear Data Sets  

E-Print Network [OSTI]

The precision of double-beta ($\\beta\\beta$) decay experimental half lives and their uncertainties is reanalyzed. The method of Benford's distributions has been applied to nuclear reaction, structure and decay data sets. First-digit distribution trend for $\\beta\\beta$-decay T$_{1/2}^{2\

B. Pritychenko

2015-01-09T23:59:59.000Z

247

Imperfect World of $??$-decay Nuclear Data Sets?  

E-Print Network [OSTI]

The precision of double-beta ($\\beta\\beta$) decay experimental half-lives and their uncertainties is reevaluated. A complementary analysis of the decay uncertainties indicates deficiencies due to small size of statistical samples, and incomplete collection of experimental information. Further experimental and theoretical efforts would lead toward more precise values of $\\beta\\beta$-decay half-lives and nuclear matrix elements.

B. Pritychenko

2015-03-11T23:59:59.000Z

248

A First Look at Tree Decay An Introduction to How Injury and Decay Affect Trees  

E-Print Network [OSTI]

A First Look at Tree Decay An Introduction to How Injury and Decay Affect Trees by Kevin T. Smith Look at Tree Decay Photosynthesis and decay are the two most essential processes in nature. Photosynthesis by green plants captures and stores energy from the sun. This energy is used to form wood

249

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

E-Print Network [OSTI]

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. Full account is taken of the strongly modified photon dispersion relation relative to vacuum. The limiting cases of relativistic and non-relativistic plasma are analyzed. The decay rate in a strongly magnetized plasma as a function of the electron number density is compared with the un-magnetized case. We find that a strong magnetic field suppresses the catalyzing influence of the plasma on the decay rate.

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

2015-01-07T23:59:59.000Z

250

The physics of kaon decays: CP violation and lepton flavor nonconservation  

SciTech Connect (OSTI)

OAK B188 The physics of kaon decays: CP violation and lepton flavor nonconservation. We discuss here the research that is likely to be done in the 1990's in the study of kaon decays. We concentrate on searches for direct CP violation and for the violation of electron- and muon-number, including approved and proposed experiments at existing facilities, and those which could be done at a facility using the proposed Fermilab Main Injector.

William R. Molzon; Bruce D. Winstein

1992-04-30T23:59:59.000Z

251

Decay of Dirac Massive Hair in the Background of Spherical Black Hole  

E-Print Network [OSTI]

The intermediate and late-time behaviour of massive Dirac hair in the static spherically symmetric black hole spacetime was studied. It was revealed that the intermediate asymptotic pattern of decay of massive Dirac spinor hair is dependent on the mass of the field under consideration as well as the multiple number of the wave mode. The long-lived oscillatory tail observed at timelike infinity in the considered background decays slowly as t^{-5/6}.

Rafa? Moderski; Marek Rogatko

2008-05-06T23:59:59.000Z

252

PHYSICAL REVIEW C 89, 064308 (2014) Chiral two-body currents and neutrinoless double-decay in the quasiparticle  

E-Print Network [OSTI]

, then lepton number conservation violating processes could be observable (e.g. the neutrinoless double beta decay discussed in x 3 and the #23; ! #23; \\oscillations"). Massive Majorana neutrinos have #22; #23

Engel, Jonathan

253

Elements of number theory  

E-Print Network [OSTI]

The dissertation argues for the necessity of a morphosemantic theory of number, that is, a theory of number serviceable both to semantics and morphology. The basis for this position, and the empirical core of the dissertation, ...

Harbour, Daniel, 1975-

2003-01-01T23:59:59.000Z

254

Results on charmed meson decays from Mark III  

SciTech Connect (OSTI)

We report recent results on charmed meson decays, obtained using the Mark III detector at SPEAR. The first topic discussed is the observation of e/sup +/e/sup -/ ..-->.. D/sub s/D/sub s/* at ..sqrt..s = 4.14 GeV. The D/sub s/* is detected as a peak in the mass distribution recoiling from D/sub s//sup + -/ ..-->.. phi..pi../sup + -/. The mass of the D/sub s/* is found to be (2109.3 +- 2.1 +- 3.1)MeV/c/sup 2/, yielding a D/sub s/*-D/sub s/ mass difference of (137.9 +- 2.1 +- 4.3) MeV/c/sup 2/. The production cross section times branching ratio is also measured. Next, a search for the decay D/sup +/ ..-->.. ..mu../sup +/nu/sub ..mu../ is described. A preliminary upper limit (90% CL) on B(D/sup +/ ..-->.. ..mu../sup +/nu/sub ..mu../) of 8.4 x 10/sup -4/ is obtained, corresponding to an upper limit on the decay constant f/sub D/ of 340 MeV/c/sup 2/. Finally, we present results of a search for the lepton family number violating decay D/sup 0/ ..-->.. ..mu..e. We find B(D/sup 0/ ..-->.. ..mu..e) < 1.5 x 10/sup -4/ at 90% CL.

Wasserbaech, S.R.

1987-04-01T23:59:59.000Z

255

Neutrinoless double-beta decay and seesaw mechanism  

E-Print Network [OSTI]

From the standard seesaw mechanism of neutrino mass generation, which is based on the assumption that the lepton number is violated at a large (~10exp(+15) GeV) scale, follows that the neutrinoless double-beta decay is ruled by the Majorana neutrino mass mechanism. Within this notion, for the inverted neutrino-mass hierarchy we derive allowed ranges of half-lives of the neutrinoless double-beta decay for nuclei of experimental interest with different sets of nuclear matrix elements. The present-day results of the calculation of the neutrinoless double-beta decay nuclear matrix elements are briefly discussed. We argue that if neutrinoless double-beta decay will be observed in future experiments sensitive to the effective Majorana mass in the inverted mass hierarchy region, a comparison of the derived ranges with measured half-lives will allow us to probe the standard seesaw mechanism assuming that future cosmological data will establish the sum of neutrino masses to be about 0.2 eV.

Samoil M. Bilenky; Amand Faessler; Walter Potzel; Fedor Simkovic

2011-04-11T23:59:59.000Z

256

Dalitz plot studies in hadronic charm decays  

E-Print Network [OSTI]

Recent studies of hadronic -meson decays are reported. Some experimental searches of CP-symmetry violation using model independent methods are presented. An importance of unitarity constraints in construction of phenomenological models of the D-meson decays is underlined. The theoretical model of the D0 --> K0S pi+ pi- decays, including some two-body unitarity constraints, is described. Then a comparison of the model results with the Belle collaboration data is made. The results on the CP-violation in the D0 --> K0S pi+ pi- decays are given and the necessity to consider the CP-violation in the subsequent K0S decays is emphasized.

Leonard Lesniak

2014-11-06T23:59:59.000Z

257

International decay data evaluation project  

SciTech Connect (OSTI)

Basic concepts of, and information from, radionuclide decay are used in many applications. The author limits this discussion to the data needed for applied {gamma}-ray spectrometry; this includes applications such as nuclide identification and quantitative assay. Many of these applications require a knowledge of half-lives and radiation energies and emission probabilities. For over 50 years, people have compiled and evaluated measured data with the goal of obtaining the best values of these quantities. This has resulted in numerous sets of recommended values, many of which still have scientific, historical, or national reasons for existing. These sets show varying degrees of agreement and disagreement in the quoted values and varying time lags in incorporating new and improved experimental results. A new informational international group has been formed to carry out evaluations for radionuclides of importance in applications; it is expected that the results will become an authoritative and widely accepted set of decay data.

Helmer, R.G.

1996-10-01T23:59:59.000Z

258

$\\tau$ decays with neutral kaons  

E-Print Network [OSTI]

The branching ratio of the tau lepton to a neutral K meson is measured from a sample of approximately 200,000 tau decays recorded by the OPAL detector at centre-of-mass energies near the Z0 resonance. The measurement is based on two samples which identify one-prong tau decays with KL and KS mesons. The combined branching ratios are measured to be B(tau- -->pi- K0bar nutau) = (9.33+-0.68+-0.49)x10^-3 B(tau- -->pi- K0bar [>=1pi0] nutau) = (3.24+-0.74+-0.66)x10^-3 B(tau- -->K- K0bar [>=0pi0] nutau) = (3.30+-0.55+-0.39)x10^-3 where the first error is statistical and the second systematic.

Abbiendi, G; Ĺkesson, P F; Alexander, Gideon; Allison, J; Anderson, K J; Arcelli, S; Asai, S; Ashby, S F; Axen, D A; Azuelos, Georges; Bailey, I; Ball, A H; Barberio, E; Barlow, R J; Batley, J Richard; Baumann, S; Behnke, T; Bell, K W; Bella, G; Bellerive, A; Bentvelsen, Stanislaus Cornelius Maria; Bethke, Siegfried; Betts, S; Biebel, O; Biguzzi, A; Bloodworth, Ian J; Bock, P; Böhme, J; Boeriu, O; Bonacorsi, D; Boutemeur, M; Braibant, S; Bright-Thomas, P G; Brigliadori, L; Brown, R M; Burckhart, Helfried J; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Chrisman, D; Ciocca, C; Clarke, P E L; Clay, E; Cohen, I; Conboy, J E; Cooke, O C; Couchman, J; Couyoumtzelis, C; Coxe, R L; Cuffiani, M; Dado, S; Dallavalle, G M; Dallison, S; Davis, R; de Roeck, A; Dervan, P J; Desch, Klaus; Dienes, B; Dixit, M S; Donkers, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Estabrooks, P G; Etzion, E; Fabbri, Franco Luigi; Fanfani, A; Fanti, M; Faust, A A; Feld, L; Ferrari, P; Fiedler, F; Fierro, M; Fleck, I; Frey, A; Fürtjes, A; Futyan, D I; Gagnon, P; Gary, J W; Gaycken, G; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Gingrich, D M; Glenzinski, D A; Goldberg, J; Gorn, W; Grandi, C; Graham, K; Gross, E; Grunhaus, Jacob; Gruwé, M; Hajdu, C; Hanson, G G; Hansroul, M; Hapke, M; Harder, K; Harel, A; Hargrove, C K; Harin-Dirac, M; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, Richard J; Herten, G; Heuer, R D; Hildreth, M D; Hill, J C; Hobson, P R; Höcker, Andreas; Hoffman, K; Homer, R James; Honma, A K; Horváth, D; Hossain, K R; Howard, R; Hüntemeyer, P; Igo-Kemenes, P; Imrie, D C; Ishii, K; Jacob, F R; Jawahery, A; Jeremie, H; Jimack, Martin Paul; Jones, C R; Jovanovic, P; Junk, T R; Kanaya, N; Kanzaki, J I; Karapetian, G V; Karlen, D A; Kartvelishvili, V G; Kawagoe, K; Kawamoto, T; Kayal, P I; Keeler, Richard K; Kellogg, R G; Kennedy, B W; Kim, D H; Klier, A; Kobayashi, T; Kobel, M; Kokott, T P; Kolrep, M; Komamiya, S; Kowalewski, R V; Kress, T; Krieger, P; Von Krogh, J; Kühl, T; Kupper, M; Kyberd, P; Lafferty, G D; Landsman, Hagar Yaël; Lanske, D; Lauber, J; Lawson, I; Layter, J G; Lellouch, Daniel; Letts, J; Levinson, L; Liebisch, R; Lillich, J; List, B; Littlewood, C; Lloyd, A W; Lloyd, S L; Loebinger, F K; Long, G D; Losty, Michael J; Lü, J; Ludwig, J; Macchiolo, A; MacPherson, A L; Mader, W F; Mannelli, M; Marcellini, S; Marchant, T E; Martin, A J; Martin, J P; Martínez, G; Mashimo, T; Mättig, P; McDonald, W J; McKenna, J A; McKigney, E A; McMahon, T J; McPherson, R A; Meijers, F; Méndez-Lorenzo, P; Merritt, F S; Mes, H; Meyer, I; Michelini, Aldo; Mihara, S; Mikenberg, G; Miller, D J; Mohr, W; Montanari, A; Mori, T; Nagai, K; Nakamura, I; Neal, H A; Nisius, R; O'Neale, S W; Oakham, F G; Odorici, F; Ögren, H O; Okpara, A N; Oreglia, M J; Orito, S; Pásztor, G; Pater, J R; Patrick, G N; Patt, J; Pérez-Ochoa, R; Petzold, S; Pfeifenschneider, P; Pilcher, J E; Pinfold, James L; Plane, D E; Poli, B; Polok, J; Przybycien, M B; Quadt, A; Rembser, C; Rick, Hartmut; Robins, S A; Rodning, N L; Roney, J M; Rosati, S; Roscoe, K; Rossi, A M; Rozen, Y; Runge, K; Runólfsson, O; Rust, D R; Sachs, K; Saeki, T; Sahr, O; Sang, W M; Sarkisyan-Grinbaum, E; Sbarra, C; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schieck, J; Schmitt, S; Schöning, A; Schröder, M; Schumacher, M; Schwick, C; Scott, W G; Seuster, R; Shears, T G; Shen, B C; Shepherd-Themistocleous, C H; Sherwood, P; Siroli, G P; Skuja, A; Smith, A M; Snow, G A; Sobie, Randall J; Söldner-Rembold, S; Spagnolo, S; Sproston, M; Stahl, A; Stephens, K; Stoll, K; Strom, D; Ströhmer, R; Surrow, B; Talbot, S D; Taras, P; Tarem, S; Teuscher, R; Thiergen, M; Thomas, J; Thomson, M A; Torrence, E; Towers, S; Trefzger, T M; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Van Kooten, R; Vannerem, P; Verzocchi, M; Voss, H; Wäckerle, F; Waller, D; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wetterling, D; White, J S; Wilson, G W; Wilson, J A; Wyatt, T R; Yamashita, S; Zacek, V; Zer-Zion, D

2000-01-01T23:59:59.000Z

259

Autoresonant soliton and decay pumping  

E-Print Network [OSTI]

The primary resonance equation in partial derivatives with external force and slowly varying frequency is derived. The leading-order term of asymptotic solution is constructed as a soliton with growing amplitude when time is large. This growing solution is obtained due to the decaying amplitude of the external force. A necessary condition for the growth of the solution in dissipative media is obtained also.

O. M. Kiselev

2013-01-29T23:59:59.000Z

260

Speeding-up Thorium decay  

E-Print Network [OSTI]

We show that cavitation of a solution of thorium-228 in water induces its transformation at a rate 10000 times faster than the natural radioactive decay would do. This result agrees with the alteration of the secular equilibrium of thorium-234 obtained by a Russian team via explosion of titanium foils in water and solutions. These evidences further support some preliminary clues for the possibility of piezonuclear reactions (namely nuclear reactions induced by pressure waves) obtained in the last ten years.

F. Cardone; R. Mignani; A. Petrucci

2007-10-26T23:59:59.000Z

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


261

Phenomenology of a leptonic goldstino and invisible Higgs boson decays  

E-Print Network [OSTI]

Non-linearly realized supersymmetry, combined with the Standard Model field content and SU(3)XSU(2)XU(1) gauge invariance, permits local dimension-six operators involving a goldstino, a lepton doublet and a Higgs doublet. These interactions preserve total lepton number if the left-handed goldstino transforms as an antilepton. We discuss the resulting phenomenology, in the simple limit where the new couplings involve only one lepton family, thus conserving also lepton flavour. Both the Z boson and the Higgs boson can decay into a neutrino and a goldstino: the present limits from the invisible Z width and from other observables leave room for the striking possibility of a Higgs boson decaying dominantly, or at least with a sizable branching ratio, via such an invisible mode. We finally comment on the perspectives at hadron and lepton colliders, and on possible extensions of our analysis.

Ignatios Antoniadis; Marc Tuckmantel; Fabio Zwirner

2005-03-23T23:59:59.000Z

262

Dalitz Analysis of B=>Khh Decays at Belle  

E-Print Network [OSTI]

We report results on the Dalitz analysis of three-body charmless B+=>K+pi+pi-, B0=>K0pi+pi- and B+=>K+K+K- decays including searches for direct CP violation in the B+=>K+pi+pi- mode. Branching fractions for a number of quasi-two-body intermediate states are reported. We also observe evidence with 3.9 sigma significance for a large direct CP violation in B+-=>rho(770)0K+- channel. This is the first evidence for CP violation in a charged meson decay. The results are obtained using a Dalitz analysis technique with a large data sample of BBbar pairs collected with the Belle detector operating at the KEKB asymmetric energy e+e- collider.

Alexey Garmash; for the Belle Collaboration

2005-10-21T23:59:59.000Z

263

Nuclear moments for the neutrinoless double beta decay II  

E-Print Network [OSTI]

The recently developed formalism for the evaluation of nuclear form factors in neutrinoless double beta decay is applied to $^{48}Ca$, $^{76}Ge$, $^{82}Se$, $^{100}Mo$, $^{128}Te$ and $^{130}Te$ nuclei. Explicit analytical expressions that follows from this theoretical development, in the single mode model for the decay of $^{48}Ca$, have been worked out. They are useful both for testing the full numerical calculations, and for analytically checking the consistency with other formalisms. Large configuration space calculations are compared with previous studies, where alternative formulations were used. Yet, besides using the G-matrix as residual interaction, we here use a simple $\\delta$-force. Attention is paid to the connected effects of the short range nuclear correlations and the finite nucleon size. Constraints on lepton number violating terms in the weak Hamiltonian (effective neutrino Majorana mass and effective right-handed current coupling strengths) are deduced.

C. Barbero; F. Krmpoti?; A. Mariano; D. Tadi?

1999-04-12T23:59:59.000Z

264

Decay channels and decay rates for the hydrogen-antihydrogen quasimolecule  

SciTech Connect (OSTI)

Calculations of leptonic and hadronic annihilation rates in the hydrogen-antihydrogen molecule are presented. Both the leptonic potential and leptonic wave function are evaluated within the Born-Oppenheimer approximation employing the Ritz variational principle. Nonadiabatic corrections to the leptonic potential are also obtained. Explicitly correlated Gaussians are employed as basis functions, which describe accurately the hydrogen-antihydrogen interaction. Given the leptonic potential the hadronic part of the wave function for each molecular level of the hydrogen-antihydrogen quasimolecule is calculated by solving the corresponding Schroedinger equation by means of precise B-spline representations. The decay rates of the quasimolecule into separate positronium and protonium systems are estimated for a number of molecular levels. Utilizing the leptonic and hadronic wave functions the leptonic- and hadronic-annihilation rates for different molecular levels are computed.

Labzowsky, L. [Institute of Physics, St. Petersburg State University, 198904, Uljanovskaya 1, Petrodvorets, St. Petersburg (Russian Federation); Petersburg Nuclear Physics Institute, 188350, Gatchina, St. Petersburg (Russian Federation); Sharipov, V. [Institute of Physics, St. Petersburg State University, 198904, Uljanovskaya 1, Petrodvorets, St. Petersburg (Russian Federation); Prozorov, A. [Institute of Physics, St. Petersburg State University, 198904, Uljanovskaya 1, Petrodvorets, St. Petersburg (Russian Federation); Max-Planck Institut fuer Physik Komplexer Systeme, Noethnitzerstrasse 38, D-01187, Dresden (Germany); Plunien, G.; Soff, G. [Technische Universitaet Dresden, Mommsenstrasse 13, D-01062, Dresden (Germany)

2005-08-15T23:59:59.000Z

265

Alpha Backgrounds for HPGe Detectors in Neutrinoless Double-Beta Decay Experiments  

E-Print Network [OSTI]

The Majorana Experiment will use arrays of enriched HPGe detectors to search for the neutrinoless double-beta decay of 76Ge. Such a decay, if found, would show lepton-number violation and confirm the Majorana nature of the neutrino. Searches for such rare events are hindered by obscuring backgrounds which must be understood and mitigated as much as possible. A potentially important background contribution to this and other double-beta decay experiments could come from decays of alpha-emitting isotopes in the 232Th and 238U decay chains on or near the surfaces of the detectors. An alpha particle emitted external to an HPGe crystal can lose energy before entering the active region of the detector, either in some external-bulk material or within the dead region of the crystal. The measured energy of the event will only correspond to a partial amount of the total kinetic energy of the alpha and might obscure the signal from neutrinoless double-beta decay. A test stand was built and measurements were performed to quantitatively assess this background. We present results from these measurements and compare them to simulations using Geant4. These results are then used to measure the alpha backgrounds in an underground detector in situ. We also make estimates of surface contamination tolerances for double-beta decay experiments using solid-state detectors.

R. A. Johnson; T. H. Burritt; S. R. Elliott; V. M. Gehman; V. E. Guiseppe; J. F. Wilkerson

2011-12-30T23:59:59.000Z

266

Alpha Backgrounds for HPGe Detectors in Neutrinoless Double-Beta Decay Experiments  

SciTech Connect (OSTI)

The Majorana Experiment will use arrays of enriched HPGe detectors to search for the neutrinoless double-beta decay of 76Ge. Such a decay, if found, would show lepton-number violation and confirm the Majorana nature of the neutrino. Searches for such rare events are hindered by obscuring backgrounds which must be understood and mitigated as much as possible. A potentially important background contribution to this and other double-beta decay experiments could come from decays of alpha-emitting isotopes in the 232Th and 238U decay chains on or near the surfaces of the detectors. An alpha particle emitted external to an HPGe crystal can lose energy before entering the active region of the detector, either in some external-bulk material or within the dead region of the crystal. The measured energy of the event will only correspond to a partial amount of the total kinetic energy of the alpha and might obscure the signal from neutrinoless double-beta decay. A test stand was built and measurements were performed to quantitatively assess this background. We present results from these measurements and compare them to simulations using Geant4. These results are then used to measure the alpha backgrounds in an underground detector in situ. We also make estimates of surface contamination tolerances for double-beta decay experiments using solid-state detectors.

Johnson, R. A. [University of Washington, Seattle; Burritt, T. H. [University of Washington, Seattle; Elliott, S. R. [Los Alamos National Laboratory (LANL); Gehman, V. M. [Los Alamos National Laboratory (LANL); Guiseppe, V.E. [University of South Dakota; Wilkerson, J. F. [UNC/Triangle Univ. Nucl. Lab, Durham, NC/ORNL

2012-01-01T23:59:59.000Z

267

Radiative Decay of Bubble Oscillations in a Compressible Fluid  

E-Print Network [OSTI]

Consider the dynamics of a gas bubble in an inviscid, compressible liquid with surface tension. Kinematic and dynamic boundary conditions couple the bubble surface deformation dynamics with the dynamics of waves in the fluid. This system has a spherical equilibrium state, resulting from the balance of the pressure at infinity and the gas pressure within the bubble. We study the linearized dynamics about this equilibrium state in a center of mass frame: 1) We prove that the velocity potential and bubble surface perturbation satisfy point-wise in space exponential time-decay estimates. 2) The time-decay rate is governed by scattering resonances, eigenvalues of a non-selfadjoint spectral problem. These are pole singularities in the lower half plane of the analytic continuation of a resolvent operator from the upper half plane, across the real axis into the lower half plane. 3) The time-decay estimates are a consequence of resonance mode expansions for the velocity potential and bubble surface perturbations. 4) For small compressibility (Mach number, a ratio of bubble wall velocity to sound speed, \\epsilon), this is a singular perturbation of the incompressible limit. The scattering resonances which govern the anomalously slow time-decay, are {\\it Rayleigh resonances}. Asymptotics, supported by high-precision numerical studies, indicate that the Rayleigh resonances which are closest to the real axis satisfy | \\frac{\\Im \\lambda_\\star(\\epsilon)}{\\Re \\lambda_\\star(\\epsilon)} | = {\\cal O} (\\exp(-\\kappa\\ \\We\\ \\epsilon^{-2})), \\kappa>0. Here, \\We denotes the Weber number, a dimensionless ratio comparing inertia and surface tension. 5) To obtain the above results we prove a general result, of independent interest, estimating the Neumann to Dirichlet map for the wave equation, exterior to a sphere.

A. M. Shapiro; M. I. Weinstein

2011-01-01T23:59:59.000Z

268

Neutrinoless double beta decay experiments  

E-Print Network [OSTI]

The study of neutrinoless double beta decay is of outmost importance for neutrino physics. It is considered to be the gold plated channel to probe the fundamental character of neutrinos and to determine the neutrino mass. From the experimental point about nine different isotopes are explored for the search. After a general introduction follows a short discussion on nuclear matrix element calculations and supportive measurements. The current experimental status of double beta searches is presented followed by a short discussion of the ideas and proposals for large scale experiments.

K. Zuber

2006-10-04T23:59:59.000Z

269

Definitions Numbered Space  

E-Print Network [OSTI]

Definitions · Numbered Space ­ a single space marked with a number and reserved for a single permit 24/7 · Unnumbered Space ­ a space which can be used by any customer allowed to park in that lot. High Low Average Question 4: If I buy a staff permit for an UNNUMBERED* space in a non-gated surface

Behmer, Spencer T.

270

Neutrinoless Double Beta Decay and CP Violation  

E-Print Network [OSTI]

We study the relation between the Majorana neutrino mass matrices and the neutrinoless double beta decay when CP is not conserved. We give an explicit form of the decay rate in terms of a rephasing invariant quantity and demonstrate that in the presence of CP violation it is impossible to have vanishing neutrinoless double beta decay in the case of two neutrino generations (or when the third generation leptons do not mix with other leptons and hence decouple).

Patrick J. O'Donnell; Utpal Sarkar

1993-05-27T23:59:59.000Z

271

Dental Decay Among Texas School Children.  

E-Print Network [OSTI]

more often found ama older than the younger ones. With all children the numb( ing decayed 6-year molars increased rapidly with age up or 14 years. lightly more girls than boys in each race had decayed tee 'he data secured in this study suggest a... to Caries i vith Other Recent Studies I AcknowIedgm Summary Literature Ci ents -_---. ted -------- CTIN NO. 491 AUGUST, 1934 DENTAL DECAY AMONG TEXAS SCHOOL CHILDREN* sometix extensi Seve: aualifif agcum someti] diet (6 to curl...

Whitacre, Jessie (Jessie Opal)

1934-01-01T23:59:59.000Z

272

Kinetic Energy Decay Rates of Supersonic and Super-Alfvenic Turbulence in Star-Forming Clouds  

E-Print Network [OSTI]

We present numerical studies of compressible, decaying turbulence, with and without magnetic fields, with initial rms Alfven and Mach numbers ranging up to five, and apply the results to the question of the support of star-forming interstellar clouds of molecular gas. We find that, in 1D, magnetized turbulence actually decays faster than unmagnetized turbulence. In all the regimes that we have studied 3D turbulence-super-Alfvenic, supersonic, sub-Alfvenic, and subsonic-the kinetic energy decays as (t-t0)^(-x), with 0.85 < x < 1.2. We compared results from two entirely different algorithms in the unmagnetized case, and have performed extensive resolution studies in all cases, reaching resolutions of 256^3 zones or 350,000 particles. We conclude that the observed long lifetimes and supersonic motions in molecular clouds must be due to external driving, as undriven turbulence decays far too fast to explain the observations.

Mordecai-Mark Mac Low; Ralf S. Klessen; Andreas Burkert; Michael D. Smith

1997-12-01T23:59:59.000Z

273

Review of double beta decay experiments  

E-Print Network [OSTI]

The brief review of current experiments on search and studying of double beta decay processes is done. Best present limits on $\\langle m_{\

A. S. Barabash

2014-03-12T23:59:59.000Z

274

Nuclear beta-decay measurements and |Vud|  

E-Print Network [OSTI]

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

Dan Melconian

2011-08-11T23:59:59.000Z

275

Spectroscopy of element 115 decay chains  

SciTech Connect (OSTI)

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

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

2013-01-01T23:59:59.000Z

276

Neutrinoless Double Beta Decay: Present and Future  

E-Print Network [OSTI]

Present status, and future plans for Double Beta Decay searches are reviewed. Given the recent observations of neutrino oscillations, a possibility to observe $\\beta\\beta(0\

Oliviero Cremonesi

2002-10-04T23:59:59.000Z

277

Review of double beta decay experiments  

E-Print Network [OSTI]

The brief review of current experiments on search and studying of double beta decay processes is done. Best present limits on $\\langle m_{\

Barabash, A S

2014-01-01T23:59:59.000Z

278

Displacement Echoes: Classical Decay and Quantum Freeze  

E-Print Network [OSTI]

Motivated by neutron scattering experiments, we investigate the decay of the fidelity with which a wave packet is reconstructed by a perfect time-reversal operation performed after a phase space displacement. In the semiclassical limit, we show that the decay rate is generically given by the Lyapunov exponent of the classical dynamics. For small displacements, we additionally show that, following a short-time Lyapunov decay, the decay freezes well above the ergodic value because of quantum effects. Our analytical results are corroborated by numerical simulations.

Cyril Petitjean; Diego V. Bevilaqua; Eric J. Heller; Philippe Jacquod

2007-04-23T23:59:59.000Z

279

Phenomenology of charmless hadronic B decays  

E-Print Network [OSTI]

The decays of $B$ mesons to a pair of charmless pseudoscalar mesons ($PP$ decays) or to a vector and pseudoscalar meson ($VP$ decays) have been analyzed within the framework of flavor SU(3) symmetry and the Kobayashi-Maskawa mechanism of CP violation. Separate $PP$ and $VP$ fits proved to be successful in describing the experimental data (branching ratios, CP asymmetries and time-dependent parameters). Decay magnitudes and relative weak and strong phases have been extracted from the fits. Values of the weak phase $\\gamma$ were found to be consistent with the current indirect bounds from other analyses of CKM parameters.

Suprun, D A

2005-01-01T23:59:59.000Z

280

Phenomenology of charmless hadronic B decays  

E-Print Network [OSTI]

The decays of $B$ mesons to a pair of charmless pseudoscalar mesons ($PP$ decays) or to a vector and pseudoscalar meson ($VP$ decays) have been analyzed within the framework of flavor SU(3) symmetry and the Kobayashi-Maskawa mechanism of CP violation. Separate $PP$ and $VP$ fits proved to be successful in describing the experimental data (branching ratios, CP asymmetries and time-dependent parameters). Decay magnitudes and relative weak and strong phases have been extracted from the fits. Values of the weak phase $\\gamma$ were found to be consistent with the current indirect bounds from other analyses of CKM parameters.

Denis A. Suprun

2004-10-22T23:59:59.000Z

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


281

The Decay of the Neutron or Beta Decay, the Big Bang, and the...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Decay of the Neutron or Beta Decay, the Big Bang, and the Left-Handed Universe Apr 03 2014 01:00 PM - 02:30 PM Geoffrey L. Greene Physics Division, ORNL Research Accelerator...

282

Search For Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

The HEIDELBERG-MOSCOW experiment, which is the most sensitive double beta decay experiment since ten years has been regularly continued until end of November 2003. An analysis of the data has been performed already until May 20, 2003. The experiment yields now, on a 4? level, evidence for lepton number violation and proves that the neutrino is a Majorana particle. It further shows that neutrino masses are degenerate. In addition it puts several stringent constraints on other physics beyond the Standard Model. Among others it opens the door to test various supersymmetric theory scenarios, for example it gives the sharpest in the R-parity violating part of the superpotential, and limit on the parameter ? ? 111 gives information on the splitting of the sneutrino-antisneutrino system. The result from the HEIDELBERG-MOSCOW experiment is consistent with recent results from CMB investigations, with high energy cosmic rays, with the result from the g-2 experiment and with recent theoretical work. It is indirectly supported by the analysis of other Ge double beta experiments. Recent criticism of various kind has been shown to be wrong, among others by measurements performed in 2003 with a 214Bi source ( 226Ra), by simulation of the background in the range of Q?? by GEANT4, and by deeper investigation of statistical features such as sensitivity of peak search, and relevance of width of window of analysis. 1

H. V. Klapdor-kleingrothaus *a; I. V. Krivosheina A; A. Dietz A

2004-01-01T23:59:59.000Z

283

DOE/ID-Number  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

performance and PSC in NPPs and the latest information on mobile devices and software technology in order to explore a number of usage scenarios. In their research, the team...

284

Precision Measurement of the Decay Rate of 7Be in Host Materials  

E-Print Network [OSTI]

A controlled and precise determination of the cross-sections of the fusion reactions 7Be(p,gamma)8B and 3He(4He,gamma)7Be, which play an important role in determining the solar neutrino flux, necessitates the knowledge of a precise value of the electron-capture half-life of 7Be. This half-life may depend on the material hosting the 7Be atoms via small modifications of the electron density around the 7Be nucleus. In this brief communication we report on the measurement of 7Be implanted in four materials: copper, aluminum, sapphire and PVC. The four results are consistent with a null host dependence within two standard deviations and their weighted average of 53.236(39)d agrees very well with the adopted value in the literature, 53.22(6)d. The present results may exhibit a slight (0.22%) increase of the half-life at room temperature for metals compared to insulators that requires further studies.

Y. Nir-El; G. Haquin; Z. Yungreiss; M. Hass; G. Goldring; S. K. Chamoli; B. S. Nara Singh; S. Lakshmi; U. Koester; N. Champault; A. Dorsival; G. Georgiev; V. N. Fedoseyev; B. A. Marsh; D. Schumann; G. Heidenreich; S. Teichmann

2006-12-03T23:59:59.000Z

285

Survey of lepton number violation via effective operators  

SciTech Connect (OSTI)

We survey 129 lepton number violating effective operators, consistent with the minimal standard model gauge group and particle content, of mass dimension up to and including 11. Upon requiring that each one radiatively generates the observed neutrino masses, we extract an associated characteristic cutoff energy scale which we use to calculate other observable manifestations of these operators for a number of current and future experimental probes, concentrating on lepton number violating phenomena. These include searches for neutrinoless double-beta decay and rare meson, lepton, and gauge boson decays. We also consider searches at hadron/lepton collider facilities in anticipation of the CERN LHC and the future ILC. We find that some operators are already disfavored by current data, while more are ripe to be probed by next-generation experiments. We also find that our current understanding of lepton mixing disfavors a subset of higher dimensional operators. While neutrinoless double-beta decay is the most promising signature of lepton number violation for the majority of operators, a handful is best probed by other means. We argue that a combination of constraints from various independent experimental sources will help to pinpoint the ''correct'' model of neutrino mass, or at least aid in narrowing down the set of possibilities.

Gouvea, Andre de; Jenkins, James [Northwestern University, Department of Physics and Astronomy, 2145 Sheridan Road, Evanston, Illinois 60208 (United States)

2008-01-01T23:59:59.000Z

286

Neutrinoless Double-Beta Decay: a Probe of Physics Beyond the Standard Model  

E-Print Network [OSTI]

In the Standard Model the total lepton number is conserved. Thus, neutrinoless double-beta decay, in which the total lepton number is violated by two units, is a probe of physics beyond the Standard Model. After a brief summary of the present status of our knowledge of neutrino masses and mixing and an introduction to the seesaw mechanism for the generation of light Majorana neutrino masses, in this review we discuss the theory and phenomenology of neutrinoless double-beta decay. We present the basic elements of the theory of neutrinoless double-beta decay, our view of the present status of the challenging problem of the calculation of the nuclear matrix element of the process and a summary of the experimental results.

Bilenky, S M

2014-01-01T23:59:59.000Z

287

Neutrinoless Double-Beta Decay: a Probe of Physics Beyond the Standard Model  

E-Print Network [OSTI]

In the Standard Model the total lepton number is conserved. Thus, neutrinoless double-beta decay, in which the total lepton number is violated by two units, is a probe of physics beyond the Standard Model. After a brief summary of the present status of our knowledge of neutrino masses and mixing and an introduction to the seesaw mechanism for the generation of light Majorana neutrino masses, in this review we discuss the theory and phenomenology of neutrinoless double-beta decay. We present the basic elements of the theory of neutrinoless double-beta decay, our view of the present status of the challenging problem of the calculation of the nuclear matrix element of the process and a summary of the experimental results.

S. M. Bilenky; C. Giunti

2014-11-18T23:59:59.000Z

288

Observation of the radiative decay D*+-> D+gamma  

E-Print Network [OSTI]

, Livermore, CA 94551. ? Permanent address: BINP, RU-630090 Novosibirsk, Russia. 107 Permanent address: Yonsei University, Seoul 120-749, Korea. [1] See, for example, A.N. Kamal and Q.P. Xu, Phys. Lett. B 284, 421 (1992); P.J. O?Donnell and Q.P. Xu, Phys. Lett...VOLUME 80, NUMBER 18 PHYSICAL REVIEW LETTERS 4MAY 1998 Observation of the Radiative Decay D p1 !D 1 g J. Bartelt, 1 S.E. Csorna, 1 V. Jain, 1, * K.W. McLean, 1 S. Marka, 1 R. Godang, 2 K. Kinoshita, 2 I.C. Lai, 2 P. Pomianowski, 2 S. Schrenk, 21 G...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

1998-05-01T23:59:59.000Z

289

Neutrinoless Double Beta Decay and Lepton Flavor Violation  

E-Print Network [OSTI]

We point out that extensions of the Standard Model with low scale (~TeV) lepton number violation (LNV) generally lead to a pattern of lepton flavor violation (LFV) experimentally distinguishable from the one implied by models with GUT scale LNV. As a consequence, muon LFV processes provide a powerful diagnostic tool to determine whether or not the effective neutrino mass can be deduced from the rate of neutrinoless double beta decay. We discuss the role of \\mu -> e \\gamma and \\mu -> e conversion in nuclei, which will be studied with high sensitivity in forthcoming experiments.

V. Cirigliano; A. Kurylov; M. J. Ramsey-Musolf; P. Vogel

2004-06-17T23:59:59.000Z

290

Spectroscopy and decays of charm and bottom  

SciTech Connect (OSTI)

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.

Butler, J.N.

1997-10-01T23:59:59.000Z

291

Neutrino oscillations and neutrinoless double beta decay  

E-Print Network [OSTI]

The relation between neutrino oscillation parameters and neutrinoless double beta decay is studied, assuming normal and inverse hierarchies for Majorana neutrino masses. For normal hierarchy the crucial dependence on U_{e3} is explored. The link with tritium beta decay is also briefly discussed.

D. Falcone; F. Tramontano

2001-03-16T23:59:59.000Z

292

Neutrinoless double beta decay and neutrino physics  

E-Print Network [OSTI]

The connection of neutrino physics with neutrinoless double beta decay is reviewed. After presenting the current status of the PMNS matrix and the theoretical background of neutrino mass and lepton mixing, we will summarize the various implications of neutrino physics for double beta decay. The influence of light sterile neutrinos and other exotic modifications of the three neutrino picture is also discussed.

Werner Rodejohann

2012-08-20T23:59:59.000Z

293

Masses and decay properties of nuclei far from stability  

SciTech Connect (OSTI)

A macroscopic-microscopic calculation has been applied to a study of the stability of elements in the heavy and superheavy regions. A folded-Yukawa single-particle potential and a Finite-Range microscopic model were used. Calculated neutron single-particle levels are shown for the spherical nucleus of Z = 114 and A = 298. These are compared to results from an earlier version of the folded-Yukawa potential and to the results of a Woods-Saxon model. Calculated ground-state shell corrections are shown. A small local minimum is seen around Z = 110 and N = 162, which is thought to have a 40 ms half-life. The microscopic correction was calculated for single-particle wells appropriate to 15 nuclei on the line of beta stability. Results obtained with the identical microscopic corrections with the Finite-Range Droplet model for the macroscopic energy are also shown. 12 refs., 4 figs. (LEW)

Moeller, P.; Nix, J.R.; Myers, W.D.; Swiatecki, W.J.

1986-01-01T23:59:59.000Z

294

Report number codes  

SciTech Connect (OSTI)

This publication lists all report number codes processed by the Office of Scientific and Technical Information. The report codes are substantially based on the American National Standards Institute, Standard Technical Report Number (STRN)-Format and Creation Z39.23-1983. The Standard Technical Report Number (STRN) provides one of the primary methods of identifying a specific technical report. The STRN consists of two parts: The report code and the sequential number. The report code identifies the issuing organization, a specific program, or a type of document. The sequential number, which is assigned in sequence by each report issuing entity, is not included in this publication. Part I of this compilation is alphabetized by report codes followed by issuing installations. Part II lists the issuing organization followed by the assigned report code(s). In both Parts I and II, the names of issuing organizations appear for the most part in the form used at the time the reports were issued. However, for some of the more prolific installations which have had name changes, all entries have been merged under the current name.

Nelson, R.N. (ed.)

1985-05-01T23:59:59.000Z

295

In-flight decay spectroscopy of exotic light nuclei  

SciTech Connect (OSTI)

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.

Charity, R. J. [Department of Chemistry, Washington University, St. Louis, Mo 63130 (United States)

2012-11-20T23:59:59.000Z

296

Neutrinoless Double Beta Decay in Light of SNO Salt Data  

E-Print Network [OSTI]

Limits From Neutrinoless Double-Beta Decay (Rev. ),” incan also cause neutrinoless double-beta decay (see e.g. , [LBNL-53996 Neutrinoless Double Beta Decay in Light of SNO

Murayama, Hitoshi

2009-01-01T23:59:59.000Z

297

What can we learn from neutrinoless double beta decay experiments?  

E-Print Network [OSTI]

312 P. Vogel, “Limits From Neutrinoless Double-Beta Decay (Assumptions No detected neutrinoless double ?-decay lightestscale (1 ± 0.05 eV), No neutrinoless double ?-decay lightest

Bahcall, John N.

2009-01-01T23:59:59.000Z

298

Neutrinoless Double Beta Decay in Light of SNO Salt Data  

E-Print Network [OSTI]

14] P. Vogel, “Limits From Neutrinoless Double-Beta Decay (Higgs, can also cause neutrinoless double-beta decay (seeLBNL-53996 Neutrinoless Double Beta Decay in Light of SNO

Murayama, Hitoshi

2009-01-01T23:59:59.000Z

299

Application of nuclear density functionals to lepton number violating weak processes  

SciTech Connect (OSTI)

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

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

2012-10-20T23:59:59.000Z

300

New Limit on the Neutrinoless Decay of 130 C. Arnaboldi,1  

E-Print Network [OSTI]

New Limit on the Neutrinoless #12;#12; Decay of 130 Te C. Arnaboldi,1 D. R. Artusa,2 F. T. Avignone September 2005) We report the present results of CUORICINO, a search for neutrinoless double-beta (0.142501 PACS numbers: 23.40.Bw, 11.30.Fs, 14.60.Pq Great interest was stimulated recently in neutrinoless

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


301

The Majorana Demonstrator: A Search for Neutrinoless Double-beta Decay of 76Ge  

E-Print Network [OSTI]

Neutrinoless double-beta decay is a hypothesized process where in some even-even nuclei it might be possible for two neutrons to simultaneously decay into two protons and two electrons without emitting neutrinos. This is possible only if neutrinos are Majorana particles, i.e. fermions that are their own antiparticles. Neutrinos being Majorana particles would explicitly violate lepton number conservation, and might play a role in the matter-antimatter asymmetry in the universe. The observation of neutrinoless double-beta decay would also provide complementary information related to neutrino masses. The Majorana Collaboration is constructing the Majorana Demonstrator, a 40-kg modular germanium detector array, to search for the Neutrinoless double-beta decay of 76Ge and to demonstrate a background rate at or below 3 counts/(ROI-t-y) in the 4 keV region of interest (ROI) around the 2039 keV Q-value for 76Ge Neutrinoless double-beta decay. In this paper, we discuss the physics of neutrinoless double beta decay and then focus on the Majorana Demonstrator, including its design and approach to achieve ultra-low backgrounds and the status of the experiment.

Majorana Collaboration; W. Xu; N. Abgrall; F. T. Avignone III; A. S. Barabash; F. E. Bertrand; V. Brudanin; M. Busch; M. Buuck; D. Byram; A. S. Caldwell; Y-D. Chan; C. D. Christofferson; C. Cuesta; J. A. Detwiler; Yu. Efremenko; H. Ejiri; S. R. Elliott; A. Galindo-Uribarri; G. K. Giovanetti; J. Goett; M. P. Green; J. Gruszko; I. Guinn; V. E. Guiseppe; R. Henning; E. W. Hoppe; S. Howard; M. A. Howe; B. R. Jasinski; K. J. Keeter; M. F. Kidd; S. I. Konovalov; R. T. Kouzes; B. D. LaFerriere; J. Leon; J. MacMullin; R. D. Martin; S. J. Meijer; S. Mertens; J. L. Orrell; C. O'Shaughnessy; N. R. Overman; A. W. P. Poon; D. C. Radford; J. Rager; K. Rielage; R. G. H. Robertson; E. Romero-Romero; M. C. Ronquest; B. Shanks; M. Shirchenko; N. Snyder; A. M. Suriano; D. Tedeschi; J. E. Trimble; R. L. Varner; S. Vasilyev; K. Vetter; K. Vorren; B. R. White; J. F. Wilkerson; C. Wiseman; E. Yakushev; C-H. Yu; V. Yumatov

2015-01-13T23:59:59.000Z

302

Hydrodynamical simulations of the decay of high-speed molecular turbulence. I. Dense molecular regions  

E-Print Network [OSTI]

We present the results from three dimensional hydrodynamical simulations of decaying high-speed turbulence in dense molecular clouds. We compare our results, which include a detailed cooling function, molecular hydrogen chemistry and a limited C and O chemistry, to those previously obtained for decaying isothermal turbulence. After an initial phase of shock formation, power-law decay regimes are uncovered, as in the isothermal case. We find that the turbulence decays faster than in the isothermal case because the average Mach number remains higher, due to the radiative cooling. The total thermal energy, initially raised by the introduction of turbulence, decays only a little slower than the kinetic energy. We discover that molecule reformation, as the fast turbulence decays, is several times faster than that predicted for a non-turbulent medium. This is caused by moderate speed shocks which sweep through a large fraction of the volume, compressing the gas and dust. Through reformation, the molecular density and molecular column appear as complex patterns of filaments, clumps and some diffuse structure. In contrast, the molecular fraction has a wider distribution of highly distorted clumps and copious diffuse structure, so that density and molecular density are almost identically distributed during the reformation phase. We conclude that molecules form in swept-up clumps but effectively mix throughout via subsequent expansions and compressions.

Georgi Pavlovski; Michael D. Smith; Mordecai-Mark Mac Low; Alexander Rosen

2002-08-15T23:59:59.000Z

303

ALARA notes, Number 8  

SciTech Connect (OSTI)

This document contains information dealing with the lessons learned from the experience of nuclear plants. In this issue the authors tried to avoid the `tyranny` of numbers and concentrated on the main lessons learned. Topics include: filtration devices for air pollution abatement, crack repair and inspection, and remote handling equipment.

Khan, T.A.; Baum, J.W.; Beckman, M.C. [eds.] [eds.

1993-10-01T23:59:59.000Z

304

CHEMICAL SAFETY Emergency Numbers  

E-Print Network [OSTI]

- 1 - CHEMICAL SAFETY MANUAL 2010 #12;- 2 - Emergency Numbers UNBC Prince George Campus Security Prince George Campus Chemstores 6472 Chemical Safety 6472 Radiation Safety 5530 Biological Safety 5530 use, storage, handling, waste and emergency management of chemicals on the University of Northern

Bolch, Tobias

305

A number of organizations,  

E-Print Network [OSTI]

installed solar electric systems on a number of the city's buildings, including the Chicago Center for Green Technology shown here. CityofChicago Aggregated Purchasing--A Clean Energy Strategy SOLAR TODAY Aggregated Purchasing--A Clean Energy Strategy by Lori A. Bird and Edward A. Holt #12;November/December 2002 35 Power

306

auger decay spectra: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2008-01-01 44 Constraining Mass Spectra with Sterile Neutrinos from Neutrinoless Double Beta Decay, Tritium Beta Decay and Cosmology HEP - Experiment (arXiv) Summary: We...

307

A Search for Neutrinoless Double Beta Decay of Te-130.  

E-Print Network [OSTI]

??This dissertation describes an experimental search for neutrinoless double beta (0???) decay of 130Te. An observation of 0??? decay would establish that neutrinos are Majorana… (more)

Bryant, Adam Douglas

2010-01-01T23:59:59.000Z

308

ACCOUNTS PAYABLE VENDOR NUMBER GUIDE  

E-Print Network [OSTI]

ACCOUNTS PAYABLE VENDOR NUMBER GUIDE FOR DEPARTMENTS W-9 AND W-8BEN FORMS TAXPAYER ID NUMBER (TIN), FEDERAL EMPLOYER ID NUMBER (FEIN), AND EMPLOYER'S ID NUMBER (EIN) HOW TO FIND A VENDOR'S ID NUMBER IN BANNER HOW TO DETERMINE IF A VENDOR IS IN BANNER UPDATED MAY 2013 #12;Vendor Number Guide

309

B, D and K Decays  

SciTech Connect (OSTI)

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

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

2008-03-07T23:59:59.000Z

310

beta-decay study of Cu-77  

E-Print Network [OSTI]

A beta-decay study of Cu-77 has been performed at the ISOLDE mass separator with the aim to deduce its beta-decay properties and to obtain spectroscopic information on Zn-77. Neutron-rich copper isotopes were produced by means of proton- or neutron-induced fission reactions on U-238. After the production, Cu-77 was selectively laser ionized, mass separated and sent to different detection systems where beta-gamma and beta-n coincidence data were collected. We report on the deduced half-live, decay scheme, and possible spin assignment of 77Cu.

N. Patronis; H. De Witte; M. Gorska; M. Huyse; K. Kruglov; D. Pauwels; K. Van de Vel; P. Van Duppen; J. Van Roosbroeck; J. -C. Thomas; S. Franchoo; J. Cederkall; V. N. Fedoseyev; H. Fynbo; U. Georg; O. Jonsson; U. Köster; T. Materna; L. Mathieu; O. Serot; L. Weissman; W. F. Mueller; V. I. Mishin; D. Fedorov

2009-09-01T23:59:59.000Z

311

Higgs boson decay to mu mubar gamma  

E-Print Network [OSTI]

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

Ali Abbasabadi; Wayne W. Repko

2000-04-17T23:59:59.000Z

312

The strong decays of K1 resonances  

E-Print Network [OSTI]

We investigate the K1--> K pi pi strong interaction decays. Using the 3P0 quark-pair-creation model to derive the basic parametrization, we discuss in detail how to obtain the various partial wave amplitudes into the possible quasi-two-body decay channels as well as their relative phases from the currently available experimental data. We obtain the K1 mixing angle to be thetaK1= 60 deg, in agreement with previous works. Our study can be applied to extract the information needed for the photon polarization determination of the radiative B--> K1 gamma decay.

Andrey Tayduganov; Emi Kou; Alain Le Yaouanc

2011-11-27T23:59:59.000Z

313

Effects of alpha beam on the parametric decay of a parallel propagating circularly polarized Alfven wave: Hybrid simulations  

SciTech Connect (OSTI)

Alfven waves with a finite amplitude are found to be unstable to a parametric decay in low beta plasmas. In this paper, the parametric decay of a circularly polarized Alfven wave in a proton-electron-alpha plasma system is investigated with one-dimensional (1-D) hybrid simulations. In cases without alpha particles, with the increase of the wave number of the pump Alfven wave, the growth rate of the decay instability increases and the saturation amplitude of the density fluctuations slightly decrease. However, when alpha particles with a sufficiently large bulk velocity along the ambient magnetic field are included, at a definite range of the wave numbers of the pump wave, both the growth rate and the saturation amplitude of the parametric decay become much smaller and the parametric decay is heavily suppressed. At these wave numbers, the resonant condition between the alpha particles and the daughter Alfven waves is satisfied, therefore, their resonant interactions might play an important role in the suppression of the parametric decay instability.

Gao, Xinliang; Lu, Quanming; Tao, Xin; Hao, Yufei; Wang, Shui [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Science, University of Science and Technology of China, Hefei 230026 (China)] [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Science, University of Science and Technology of China, Hefei 230026 (China)

2013-09-15T23:59:59.000Z

314

Search for CP violation in D(0) decay  

E-Print Network [OSTI]

] —0.020 & A~~ & 0.180 —0.182 & A~o ~ & 0.126S —0.067 & A~o 0 & 0.031S gion lies between 1.835 and 1.895 GeV/c . The num- ber of events in the D signal region is 12734 and the number in the D signal region is 12644. The num- ber of D background events...PHYSICAL REVIE%' D VOLUME 52, NUMBER 9 1 NOVEMBER 1995 Search for CP violation in D decay J. Bartelt, S.E. Csorna, Z. Egyed, and V. Jain Vanderbilt University, Nashville, Tennessee 87285 D. Gibaut, K. Kinoshita, and P. Pomianowski Virginia...

Baringer, Philip S.

1995-11-01T23:59:59.000Z

315

Extended Coherence Time with Atom-Number Squeezed Sources  

E-Print Network [OSTI]

Coherence properties of Bose-Einstein condensates offer the potential for improved interferometric phase contrast. However, decoherence effects due to the mean-field interaction shorten the coherence time, thus limiting potential sensitivity. In this work, we demonstrate increased coherence times with number squeezed states in an optical lattice using the decay of Bloch oscillations to probe the coherence time. We extend coherence times by a factor of 2 over those expected with coherent state BEC interferometry. We observe quantitative agreement with theory both for the degree of initial number squeezing as well as for prolonged coherence times.

Wei Li; Ari K. Tuchman; Hui-Chun Chien; Mark A. Kasevich

2006-09-02T23:59:59.000Z

316

Nonlocal theory of electromagnetic wave decay into two electromagnetic waves in a rippled density plasma channel  

SciTech Connect (OSTI)

Parametric decay of a large amplitude electromagnetic wave into two electromagnetic modes in a rippled density plasma channel is investigated. The channel is taken to possess step density profile besides a density ripple of axial wave vector. The density ripple accounts for the momentum mismatch between the interacting waves and facilitates nonlinear coupling. For a given pump wave frequency, the requisite ripple wave number varies only a little w.r.t. the frequency of the low frequency decay wave. The radial localization of electromagnetic wave reduces the growth rate of the parametric instability. The growth rate decreases with the frequency of low frequency electromagnetic wave.

Sati, Priti; Tripathi, V. K. [Indian Institute of Technology, Hauz Khas, Delhi 110054 (India)

2012-12-15T23:59:59.000Z

317

Neutrinoless double-{beta} decay in the microscopic interacting boson model  

SciTech Connect (OSTI)

We present a formalism for calculating nuclear matrix elements of double-{beta} decay within the framework of the microscopic interacting boson model. We calculate Fermi, Gamow-Teller, and tensor matrix elements in the decay of Ge-Se-Mo-Te-Xe-Nd-Sm and compare our results with those of the shell-model (SM) and of the quasiparticle random-phase approximation (QRPA). Our results are in agreement with QRPA. We discuss simple features of the matrix elements and give a formula that allows one to estimate matrix elements in terms of the number of valence proton and neutron pairs.

Barea, J.; Iachello, F. [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, Connecticut 06520-8120 (United States)

2009-04-15T23:59:59.000Z

318

Shape and pairing fluctuations effects on neutrinoless double beta decay nuclear matrix elements  

E-Print Network [OSTI]

Nuclear matrix elements (NME) for the most promising candidates to detect neutrinoless double beta decay have been computed with energy density functional methods including deformation and pairing fluctuations explicitly on the same footing. The method preserves particle number and angular momentum symmetries and can be applied to any decay without additional fine tunings. The finite range density dependent Gogny force is used in the calculations. An increase of $10\\%-40\\%$ in the NME with respect to the ones found without the inclusion of pairing fluctuations is obtained, reducing the predicted half-lives of these isotopes.

Nuria López Vaquero; Tomás R. Rodríguez; J. Luis Egido

2014-01-03T23:59:59.000Z

319

Limits on tau lepton flavor violating decays in three charged leptons  

SciTech Connect (OSTI)

A search for the neutrinoless, lepton-flavor violating decay of the {tau} lepton into three charged leptons has been performed using an integrated luminosity of 468 fb{sup -1} collected with the BABAR detector at the PEP-II collider. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (1.8-3.3) x 10{sup -8} at 90% confidence level.

Cervelli, Alberto

2010-04-29T23:59:59.000Z

320

LHC and B physics probes of neutrinoless double beta decay in supersymmetry without R-parity.  

E-Print Network [OSTI]

ar X iv :0 90 3. 03 47 v3 [ he p- ph ] 24 Ju l 2 00 9 Preprint typeset in JHEP style - HYPER VERSION CAVENDISH-HEP-2009-01 DAMTP-2008-86 DO-TH-08/10 LHC and B physics probes of neutrinoless double beta decay in supersymmetry without R-parity B... , Dortmund, Germany E-mails: b.c.allanach@damtp.cam.ac.uk, kom@hep.phy.cam.ac.uk, heinrich.paes@uni-dortmund.de Abstract: In the event of an observation of neutrinoless double beta decay, a relevant question would be: what lepton number violating physics...

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

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


321

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

E-Print Network [OSTI]

ar X iv :0 90 2. 46 97 v1 [ he p- ph ] 26 Fe b 2 00 9 CAVENDISH-HEP-2009-03, DAMTP-2009-15, DO-TH-09/01 Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism B. C. Allanach? DAMTP, University of Cambridge... ) In the minimal supersymmetric extension to the Standard Model, a non-zero lepton number violating coupling ??111 predicts both neutrinoless double beta decay and resonant single slepton production at the LHC. We show that, in this case, if neutrinoless double...

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

322

Search for neutrinoless decays tau -> lhh and tau -> lV0  

E-Print Network [OSTI]

We have searched for neutrinoless tau lepton decays into l h h or l V0, where l stands for an electron or muon, h for a charged light hadron, pi or K, and V0 for a neutral vector meson, rho, K*(892) and phi, using a 158 /fb data sample collected with the Belle detector at the KEKB e+e- collider. Since the number of events observed are consistent with the expected background, we set upper limits on the branching fractions in the range of 1.6-8.0 x 10-7 for various decay modes at the 90% confidence level.

Y. Yusa; for the Belle Collaboration

2006-03-18T23:59:59.000Z

323

Search for LFV in Tau- to L- L+ L- Decays at BaBar  

SciTech Connect (OSTI)

We report the results of search for the neutrinoless lepton-flavor violating decay of the tau lepton into three charged leptons, performed using 376 fb{sup -1} of data collected at an e{sup +}e{sup -} center-of-mass energy around 10.58 GeV with the BaBar detector at the PEP-II. In all six decay modes considered, the number of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (4-8) x 10{sup -8} at 90% confidence level.

Giorgi, Marcello A.; /Pisa U. /INFN, Pisa

2011-11-30T23:59:59.000Z

324

Falsifying High-Scale Baryogenesis with Neutrinoless Double Beta Decay and Lepton Flavor Violation  

E-Print Network [OSTI]

Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any pre-existing baryon asymmetry of the universe. In this letter, we discuss the constraints obtained from an observation of neutrinoless double beta decay in this context. If a new physics mechanism of neutrinoless double beta decay is observed, typical scenarios of high-scale baryogenesis will be excluded unless the baryon asymmetry is stabilized via some new mechanism. We also sketch how this conclusion can be extended beyond the first lepton generation by incorporating lepton flavor violating processes.

Frank F. Deppisch; Julia Harz; Martin Hirsch; Wei-Chih Huang; Heinrich Päs

2015-03-16T23:59:59.000Z

325

Falsifying High-Scale Baryogenesis with Neutrinoless Double Beta Decay and Lepton Flavor Violation  

E-Print Network [OSTI]

Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any pre-existing baryon asymmetry of the universe. In this letter, we discuss the constraints obtained from an observation of neutrinoless double beta decay in this context. If a new physics mechanism of neutrinoless double beta decay is observed, typical scenarios of high-scale baryogenesis will be excluded unless the baryon asymmetry is stabilized via some new mechanism. We also sketch how this conclusion can be extended beyond the first lepton generation by incorporating lepton flavor violating processes.

Deppisch, Frank F; Hirsch, Martin; Huang, Wei-Chih; Päs, Heinrich

2015-01-01T23:59:59.000Z

326

Strong constraints on the rare decays Bs -> mu+ mu- and B0 -> mu+ mu-  

E-Print Network [OSTI]

A search for Bs -> mu+ mu- and B0 -> mu+ mu- decays is performed using 1.0 fb^-1 of pp collision data collected at \\sqrt{s}=7 TeV with the LHCb experiment at the Large Hadron Collider. For both decays the number of observed events is consistent with expectation from background and Standard Model signal predictions. Upper limits on the branching fractions are determined to be BR(Bs -> mu+ mu-) mu+ mu-) < 1.0 (0.81) x 10^-9 at 95% (90%) confidence level.

LHCb collaboration; R. Aaij; C. Abellan Beteta; A. Adametz; B. Adeva; M. Adinolfi; C. Adrover; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; S. Ali; G. Alkhazov; P. Alvarez Cartelle; A. A. Alves Jr; S. Amato; Y. Amhis; J. Anderson; R. B. Appleby; O. Aquines Gutierrez; F. Archilli; A. Artamonov; M. Artuso; E. Aslanides; G. Auriemma; S. Bachmann; J. J. Back; V. Balagura; W. Baldini; R. J. Barlow; C. Barschel; S. Barsuk; W. Barter; A. Bates; C. Bauer; Th. Bauer; A. Bay; J. Beddow; I. Bediaga; S. Belogurov; K. Belous; I. Belyaev; E. Ben-Haim; M. Benayoun; G. Bencivenni; S. Benson; J. Benton; R. Bernet; M. -O. Bettler; M. van Beuzekom; A. Bien; S. Bifani; T. Bird; A. Bizzeti; P. M. Bjřrnstad; T. Blake; F. Blanc; C. Blanks; J. Blouw; S. Blusk; A. Bobrov; V. Bocci; A. Bondar; N. Bondar; W. Bonivento; S. Borghi; A. Borgia; T. J. V. Bowcock; C. Bozzi; T. Brambach; J. van den Brand; J. Bressieux; D. Brett; M. Britsch; T. Britton; N. H. Brook; H. Brown; A. Büchler-Germann; I. Burducea; A. Bursche; J. Buytaert; S. Cadeddu; O. Callot; M. Calvi; M. Calvo Gomez; A. Camboni; P. Campana; A. Carbone; G. Carboni; R. Cardinale; A. Cardini; L. Carson; K. Carvalho Akiba; G. Casse; M. Cattaneo; Ch. Cauet; M. Charles; Ph. Charpentier; N. Chiapolini; M. Chrzaszcz; K. Ciba; X. Cid Vidal; G. Ciezarek; P. E. L. Clarke; M. Clemencic; H. V. Cliff; J. Closier; C. Coca; V. Coco; J. Cogan; E. Cogneras; P. Collins; A. Comerma-Montells; A. Contu; A. Cook; M. Coombes; G. Corti; B. Couturier; G. A. Cowan; R. Currie; C. D'Ambrosio; P. David; P. N. Y. David; I. De Bonis; K. De Bruyn; S. De Capua; M. De Cian; J. M. De Miranda; L. De Paula; P. De Simone; D. Decamp; M. Deckenhoff; H. Degaudenzi; L. Del Buono; C. Deplano; D. Derkach; O. Deschamps; F. Dettori; J. Dickens; H. Dijkstra; P. Diniz Batista; F. Domingo Bonal; S. Donleavy; F. Dordei; P. Dornan; A. Dosil Suárez; D. Dossett; A. Dovbnya; F. Dupertuis; R. Dzhelyadin; A. Dziurda; A. Dzyuba; S. Easo; U. Egede; V. Egorychev; S. Eidelman; D. van Eijk; F. Eisele; S. Eisenhardt; R. Ekelhof; L. Eklund; Ch. Elsasser; D. Elsby; D. Esperante Pereira; A. Falabella; C. Färber; G. Fardell; C. Farinelli; S. Farry; V. Fave; V. Fernandez Albor; M. Ferro-Luzzi; S. Filippov; C. Fitzpatrick; M. Fontana; F. Fontanelli; R. Forty; O. Francisco; M. Frank; C. Frei; M. Frosini; S. Furcas; A. Gallas Torreira; D. Galli; M. Gandelman; P. Gandini; Y. Gao; J-C. Garnier; J. Garofoli; J. Garra Tico; L. Garrido; D. Gascon; C. Gaspar; R. Gauld; N. Gauvin; M. Gersabeck; T. Gershon; Ph. Ghez; V. Gibson; V. V. Gligorov; C. Göbel; D. Golubkov; A. Golutvin; A. Gomes; H. Gordon; M. Grabalosa Gándara; R. Graciani Diaz; L. A. Granado Cardoso; E. Graugés; G. Graziani; A. Grecu; E. Greening; S. Gregson; O. Grünberg; B. Gui; E. Gushchin; Yu. Guz; T. Gys; C. Hadjivasiliou; G. Haefeli; C. Haen; S. C. Haines; T. Hampson; S. Hansmann-Menzemer; N. Harnew; J. Harrison; P. F. Harrison; T. Hartmann; J. He; V. Heijne; K. Hennessy; P. Henrard; J. A. Hernando Morata; E. van Herwijnen; E. Hicks; K. Holubyev; P. Hopchev; W. Hulsbergen; P. Hunt; T. Huse; R. S. Huston; D. Hutchcroft; D. Hynds; V. Iakovenko; P. Ilten; J. Imong; R. Jacobsson; A. Jaeger; M. Jahjah Hussein; E. Jans; F. Jansen; P. Jaton; B. Jean-Marie; F. Jing; M. John; D. Johnson; C. R. Jones; B. Jost; M. Kaballo; S. Kandybei; M. Karacson; T. M. Karbach; J. Keaveney; I. R. Kenyon; U. Kerzel; T. Ketel; A. Keune; B. Khanji; Y. M. Kim; M. Knecht; I. Komarov; R. F. Koopman; P. Koppenburg; M. Korolev; A. Kozlinskiy; L. Kravchuk; K. Kreplin; M. Kreps; G. Krocker; P. Krokovny; F. Kruse; K. Kruzelecki; M. Kucharczyk; V. Kudryavtsev; T. Kvaratskheliya; V. N. La Thi; D. Lacarrere; G. Lafferty; A. Lai; D. Lambert; R. W. Lambert; E. Lanciotti; G. Lanfranchi; C. Langenbruch; T. Latham; C. Lazzeroni; R. Le Gac; J. van Leerdam; J. -P. Lees; R. Lefévre; A. Leflat; J. Lefrançois; O. Leroy; T. Lesiak; L. Li; Y. Li; L. Li Gioi; M. Lieng; M. Liles; R. Lindner; C. Linn; B. Liu; G. Liu; J. von Loeben; J. H. Lopes; E. Lopez Asamar; N. Lopez-March; H. Lu; J. Luisier; A. Mac Raighne; F. Machefert; I. V. Machikhiliyan; F. Maciuc; O. Maev; J. Magnin; S. Malde; R. M. D. Mamunur; G. Manca; G. Mancinelli; N. Mangiafave; U. Marconi; R. Märki; J. Marks; G. Martellotti; A. Martens; L. Martin; A. Martín Sánchez; M. Martinelli; D. Martinez Santos; A. Massafferri; Z. Mathe; C. Matteuzzi; M. Matveev; E. Maurice; B. Maynard; A. Mazurov; G. McGregor; R. McNulty; M. Meissner; M. Merk; J. Merkel; S. Miglioranzi; D. A. Milanes; M. -N. Minard; J. Molina Rodriguez; S. Monteil; D. Moran; P. Morawski; R. Mountain; I. Mous; F. Muheim; K. Müller; R. Muresan; B. Muryn; B. Muster; J. Mylroie-Smith; P. Naik; T. Nakada; R. Nandakumar; I. Nasteva; M. Needham; N. Neufeld; A. D. Nguyen; C. Nguyen-Mau; M. Nicol; V. Niess; N. Nikitin; T. Nikodem; A. Nomerotski

2012-04-26T23:59:59.000Z

327

CP Violation in Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

We argue three-flavour neutrino mixing. We consider the neutrinos as Majorana particles and see how the neutrinoless double beta decay constrains the neutrino mixing angles. Our formulation is widely valid and is applied to the neutrino oscillation experiment.

T. Fukuyama; K. Matsuda; H. Nishiura

1997-08-19T23:59:59.000Z

328

Uncertainty evaluation of delayed neutron decay parameters  

E-Print Network [OSTI]

parameters fit their individual measurement data well in spite of these differences. This dissertation focuses on evaluation of the errors and methods of delayed neutron relative yields and decay constants for thermal fission of U-235. Various numerical...

Wang, Jinkai

2009-05-15T23:59:59.000Z

329

The BNL rare kaon decay program  

SciTech Connect (OSTI)

The rare kaon decay program at Brookhaven National Laboratory is reviewed. Results from the last round of experiments are briefly discussed. The three experiments currently collecting data are described. Prospects for future experiments are discussed.

Littenberg, L.

1996-12-31T23:59:59.000Z

330

New Physics Effects From B Meson Decays  

E-Print Network [OSTI]

In this talk, we point out some of the present and future possible signatures of physics beyond the Standard Model from B-meson decays, taking R-parity conserving and violating supersymmetry as illustrative examples.

Anirban Kundu

2000-03-23T23:59:59.000Z

331

Phenomenology of neutrinoless double beta decay  

E-Print Network [OSTI]

This paper reviews the current status and future outlook of neutrinoless double beta decay searches, which try to provide an answer to the fundamental question of whether neutrinos are Dirac or Majorana particles.

Gómez-Cadenas, J J

2015-01-01T23:59:59.000Z

332

Phenomenology of neutrinoless double beta decay  

E-Print Network [OSTI]

This paper reviews the current status and future outlook of neutrinoless double beta decay searches, which try to provide an answer to the fundamental question of whether neutrinos are Dirac or Majorana particles.

J. J. Gómez-Cadenas; Justo Martín-Albo

2015-02-02T23:59:59.000Z

333

Three-body decay of (6)Be  

E-Print Network [OSTI]

Three-body correlations for the ground-state decay of the lightest two-proton emitter (6)Be are studied both theoretically and experimentally. Theoretical studies are performed in a three-body hyperspherical-harmonics cluster model...

Grigorenko, L. V.; Wiser, T. D.; Mercurio, K.; Charity, R. J.; Shane, R.; Sobotka, L. G.; Elson, J. M.; Wuosmaa, A. H.; Banu, A.; McCleskey, M.; Trache, L.; Tribble, Robert E.; Zhukov, M. V.

2009-01-01T23:59:59.000Z

334

Electrical Analogs of Atomic Radiative Decay Processes  

E-Print Network [OSTI]

Simple electrical circuits are analyzed, and the results show that for high frequencies they have frequency and time responses identical to the spontaneous radiative decays of atoms. As an illustration of the analogy a ...

Fontana, Peter R.; Srivastava, Rajendra P.

1977-03-01T23:59:59.000Z

335

Phenomenology of neutrinoless double beta decay  

E-Print Network [OSTI]

This paper reviews the current status and future outlook of neutrinoless double beta decay searches, which try to provide an answer to the fundamental question of whether neutrinos are Dirac or Majorana particles.

J. J. Gómez-Cadenas; Justo Martín-Albo

2015-02-25T23:59:59.000Z

336

Can Dark Matter Decay in Dark Energy?  

E-Print Network [OSTI]

We analyze the interaction between Dark Energy and Dark Matter from a thermodynamical perspective. By assuming they have different temperatures, we study the possibility of occurring a decay from Dark Matter into Dark Energy, characterized by a negative parameter $Q$. We find that, if at least one of the fluids has non vanishing chemical potential, for instance $\\mu_x0$, the decay is possible, where $\\mu_x$ and $\\mu_{dm}$ are the chemical potentials of Dark Energy and Dark Matter, respectively. Using recent cosmological data, we find that, for a fairly simple interaction, the Dark Matter decay is favored with a probability of $\\sim 93%$ over the Dark Energy decay. This result comes from a likelihood analysis where only background evolution has been considered.

S. H. Pereira; J. F. Jesus

2009-02-26T23:59:59.000Z

337

Theory of top quark production and decay  

SciTech Connect (OSTI)

Direct and indirect information on the top quark mass and its decay modes is reviewed. The theory of top production in hadron- and electron-positron-colliders is presented.

Kuehn, J.H. [Universitaet Karlsruhe (Germany)

1997-01-01T23:59:59.000Z

338

Probing QCD with Rare Charmless $B$ Decays  

SciTech Connect (OSTI)

Rare charmless hadronic B decays are a good testing ground for QCD. In this paper we describe a selection of new measurements made by the BABAR and BELLE collaborations.

Gradl, Wolfgang

2006-07-07T23:59:59.000Z

339

Neutrinoless double beta decay with scalar bilinears  

E-Print Network [OSTI]

One possible probe to physics beyond the standard model is to look for scalar bilinears, which couple to two fermions of the standard model. We point out that the scalar bilinears allow new diagrams contributing to the neutrinoless double beta decay. The upper bound on the neutrinoless double beta decay lifetime would then give new constraints on the ratio of the masses of these scalars to their couplings to the fermions.

H. V. Klapdor-Kleingrothaus; U. Sarkar

2002-11-18T23:59:59.000Z

340

Vacuum decay in a soluble model  

SciTech Connect (OSTI)

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.

Ferraz de Camargo F, A.; Shellard, R.C.; Marques, G.C.

1984-03-15T23:59:59.000Z

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


341

NAME: STUDENT NUMBER (PID): CITY, STATE ZIP: DAYTIME PHONE NUMBER  

E-Print Network [OSTI]

NAME: STUDENT NUMBER (PID): ADDRESS: CITY, STATE ZIP: DAYTIME PHONE NUMBER: CELL PHONE NUMBER of financial institution. 14 Cell Phone Expenses 15 Other ordinary and necessary living expenses. 16 TOTAL (add

342

False Starts in History of Searches for 2{beta} Decay, or Discoverless Double Beta Decay  

SciTech Connect (OSTI)

A collection of stories is presented on discoveries of 2{beta} decay (including neutrinoless one) which were refuted in the subsequent investigations.

Tretyak, V. I. [Institute for Nuclear Research, MSP 03680, Kyiv (Ukraine)

2011-12-16T23:59:59.000Z

343

Neutrinoless Double Beta Decay and CP Violation  

E-Print Network [OSTI]

We study the relation between the Majorana neutrino mass matrices and the neutrinoless double beta decay when CP is not conserved. We give an explicit form of the decay rate in terms of a rephasing invariant quantity and demonstrate that in the presence of CP violation it is impossible to have vanishing neutrinoless double beta decay in the case of two neutrino generations (or when the third generation leptons do not mix with other leptons and hence decouple). UTPT-93-12 In the literature the relation between the Majorana neutrino mass matrices and the neutrinoless double beta decay has been studied extensively [1]. If the electron neutrino is a Majorana particle or a pseudo-Dirac particle (i.e., the symmetry of the mass matrix is not the symmetry of the weak interaction), then they can contribute to neutrinoless double beta decay, while if it is a Dirac particle then there is no neutrinoless double beta decay. A Dirac particle can be viewed as a combination of two Majorana particles

Patrick J. O’donnell; Utpal Sarkar

1993-01-01T23:59:59.000Z

344

Recent Results on Semileptonic Decays at Babar  

SciTech Connect (OSTI)

Some recent BABAR results on semileptonic decays are presented. They focus on the determination of the CKM matrix elements |V{sub ub}| and |V{sub cb}| in inclusive and exclusive b {yields} u{ell}v and b {yields} c{ell}v decays, and on form factors measurement in exclusive c {yields} s{ell}v decays. Semileptonic decays play a crucial role in the determination of the unitarity triangle parameters: decays of the b quark give access to the CKM matrix elements |V{sub ub}| and |V{sub cb}|, while charm decays provide a way to validate lattice QCD computations through form factors measurements. Such calculations provide theoretical inputs that are used, especially, in the b sector. A lot of new results have been obtained by the BABAR collaboration during the last years, thanks to the large b{bar b} and c{bar c} production cross-sections and to the large recorded statistics. Some of these measurements are presented here.

Serrano, Justine; /Orsay, LAL

2011-11-07T23:59:59.000Z

345

Ratios of heavy hadron semileptonic decay rates  

E-Print Network [OSTI]

Ratios of charmed meson and baryon semileptonic decay rates appear to be satisfactorily described by considering only the lowest-lying (S-wave) hadronic final states and assuming the kinematic factor describing phase space suppression is the same as that for free quarks. For example, the rate for $D_s$ semileptonic decay is known to be $(17.0 \\pm 5.3)%$ lower than those for $D^0$ or $D^+$, and the model accounts for this difference. When applied to hadrons containing $b$ quarks, this method implies that the $B_s$ semileptonic decay rate is about 1% higher than that of the nonstrange $B$ mesons. This small difference thus suggests surprisingly good local quark-hadron duality for $B$ semileptonic decays, complementing the expectation based on inclusive quark-hadron duality that these differences in rates should not exceed a few tenths of a percent. For $\\Lambda_b$ semileptonic decay, however, the inclusive rate is predicted to be about 13% greater than that of the nonstrange $B$ mesons. This value, representing a considerable departure from a calculation using a heavy quark expansion, is close to the corresponding experimental ratio $\\Gamma(\\Lambda_b)/ \\bar \\Gamma(B) = 1.13 \\pm 0.03$ of total decay rates.

Michael Gronau; Jonathan L. Rosner

2010-12-27T23:59:59.000Z

346

Number | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's HeatMexico:CommunityNorthwest Basin andNsbowde's blog HomeNumber"

347

Calculated final state probability distributions for T2 -decay measurements  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 1.6.1 Neutrinoless double beta decay . . . . . . . . . . . . . . . . . . . . 19 1.6.2 Cosmological

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

348

Late-time Entropy Production from Scalar Decay and Relic Neutrino Temperature  

E-Print Network [OSTI]

Entropy production from scalar decay in the era of low temperatures after neutrino decoupling will change the ratio of the relic neutrino temperature to the CMB temperature, and, hence, the value of N_eff, the effective number of neutrino species. Such scalar decay is relevant to reheating after thermal inflation, proposed to dilute massive particles, like the moduli and the gravitino, featuring in supersymmetric and string theories. The effect of such entropy production on the relic neutrino temperature ratio is calculated in a semi-analytic manner, and a recent lower bound on this ratio, obtained from the WMAP satellite and 2dF galaxy data, is used to set a lower bound of ~ 1.5 x 10^-23 Gev on the scalar decay constant, corresponding to a reheating temperature of about 3.3 Mev.

Paramita Adhya; D. Rai Chaudhuri; Steen Hannestad

2003-09-04T23:59:59.000Z

349

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

E-Print Network [OSTI]

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

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

2012-10-15T23:59:59.000Z

350

Grant Application Package CFDA Number  

E-Print Network [OSTI]

Grant Application Package CFDA Number: Opportunity Title: Offering Agency: Agency Contact: Opportunity Open Date: Opportunity Close Date: CFDA Description: Opportunity Number: Competition ID

Talley, Lynne D.

351

DRAM Decay: Using Decay Counters to Reduce Energy Consumption in DRAMs  

E-Print Network [OSTI]

DRAM Decay: Using Decay Counters to Reduce Energy Consumption in DRAMs Mrinmoy Ghosh Hsien-Hsin S. Lee School of Electrical and Computer Engineering Georgia Institute of Technology Atlanta, GA 30332 technology they use. For each refresh in a DRAM row, the stored information in each cell is read out

Lee, Hsien-Hsin "Sean"

352

Atomic nuclei decay modes by spontaneous emission of heavy ions  

SciTech Connect (OSTI)

The great majority of the known nuclides with Z>40, including the so-called stable nuclides, are metastable with respect to several modes of spontaneous superasymmetric splitting. A model extended from the fission theory of alpha decay allows one to estimate the lifetimes and the branching ratios relative to the alpha decay for these natural radioactivities. From a huge amount of systematic calculations it is concluded that the process should proceed with maximum intensity in the trans-lead nuclei, where the minimum lifetime is obtained from parent-emitted heavy ion combinations leading to a magic (/sup 208/Pb) or almost magic daughter nucleus. More than 140 nuclides with atomic number smaller than 25 are possible candidates to be emitted from heavy nuclei, with half-lives in the range of 10/sup 10/--10/sup 30/ s: /sup 5/He, /sup 8en-dash10/Be, /sup 11,12/B, /sup 12en-dash16/C, /sup 13en-dash17/N, /sup 15en-dash22/O, /sup 18en-dash23/F, /sup 20en-dash26/Ne, /sup 23en-dash28/Na, /sup 23en-dash30/Mg, /sup 27en-dash32/Al, /sup 28en-dash36/Si, /sup 31en-dash39/P, /sup 32en-dash42/S, /sup 35en-dash45/Cl, /sup 37en-dash47/Ar, /sup 40en-dash49/ K, . .Ca, /sup 44en-dash53/ Sc, /sup 46en-dash53/Ti, /sup 48en-dash54/V, and /sup 49en-dash55/ Cr. The shell structure and the pairing effects are clearly manifested in these new decay modes.

Poenaru, D.N.; Ivascu, M.; Sndulescu, A.; Greiner, W.

1985-08-01T23:59:59.000Z

353

Effects of Beta-Decays of Excited-State Nuclei on the Astrophysical r-Process  

E-Print Network [OSTI]

A rudimentary calculation is employed to evaluate the possible effects of beta- decays of excited-state nuclei on the astrophysical r-process. Single-particle levels calculated with the FRDM are adapted to the calculation of beta-decay rates of these excited-state nuclei. Quantum numbers are determined based on proximity to Nilson model levels. The resulting rates are used in an r-process network calculation in which a supernova hot-bubble model is coupled to an extensive network calculation including all nuclei between the valley of stability and the neutron drip line and with masses ABeta-decay rates are included as functional forms of the environmental temperature. While the decay rate model used is simple and phenomenological, it is consistent across all 3700 nuclei involved in the r-process network calculation. This represents an approximate first estimate to gauge the possible effects of excited-state beta-decays on r-process freeze-out abundances.

M. A. Famiano; R. N. Boyd; T. Kajino; K. Otsuki; M. Terasawa; G. J. Mathews

2008-08-07T23:59:59.000Z

354

Beta processes in a high-temperature field and nuclear multibeta decays  

SciTech Connect (OSTI)

Sources of the temperature dependence of rates of nuclear beta processes in matter of massive stars are systematized. Electron and positron beta decays and electron capture (K capture and the capture of unbound electrons) fromexcited nuclear states (thermal decays) are considered along with the photobeta decays from ground and excited nuclear states. The possible quantum degeneracy of an electron gas in matter and the degree of ionization of an atomic K shell in a high-temperature field are taken into account. For a number of multidecay odd-nuclei, the temperature dependences of the ratios of the total rates of their {beta}{sup -} decays to the sum of the total rates over all of decay modes for the same nuclei are calculated in the range of nuclear temperature from 2 to 3 Multiplication-Sign 10{sup 9} K. It is shown that the deviation of this ratio from the experimental value obtained at 'normal' temperature may be quite sizable. This circumstance should be taken into account in models that consider the problem of synthesis of nuclei in matter of massive stars.

Kopytin, I. V., E-mail: kopytin@yandex.ru; Hussain, Imad A. [Voronezh State University (Russian Federation)] [Voronezh State University (Russian Federation)

2013-11-15T23:59:59.000Z

355

Baryons and Dark Matter from the Late Decay of a Supersymmetric Condensate  

E-Print Network [OSTI]

The possibility that both the baryon asymmetry and dark matter arise from the late decay of a population of supersymmetric particles is considered. If the decay takes place below the LSP freeze out temperature, a nonthermal distribution of LSPs results. With conserved $R$ parity these relic LSPs contribute to the dark matter density. A net asymmetry can exist in the population of decaying particles if it arises from coherent production along a supersymmetric flat direction. The asymmetry is transferred to baryons if the condensate decays through the lowest order nonrenormalizable operators which couple to $R$ odd combinations of standard model particles. This also ensures at least one LSP per decay. The relic baryon and LSP number densities are then roughly equal. The ratio of baryon to dark matter densities is then naturally $\\Omegab / \\OmegaLSP \\sim {\\cal O}(\\mb / \\mLSP)$. The resulting upper limit on the LSP mass is model dependent but in the range ${\\cal O}(30-140)$ GeV. The total relic density is related to the order at which the flat direction which gives rise to the condensate is lifted. The observed density is obtained for a direction which is lifted by a fourth order Planck scale suppressed operator in the superpotential.

Scott Thomas

1995-06-09T23:59:59.000Z

356

The search for neutrinoless double beta decay  

E-Print Network [OSTI]

In the last two decades the search for neutrinoless double beta decay has evolved into one of the highest priorities for understanding neutrinos and the origin of mass. The main reason for this paradigm shift has been the discovery of neutrino oscillations, which clearly established the existence of massive neutrinos. An additional motivation for conducting such searches comes from the existence of an unconfirmed, but not refuted, claim of evidence for neutrinoless double decay in $^{76}\\text{Ge}$. As a consequence, a new generation of experiments, employing different detection techniques and $\\beta\\beta$ isotopes, is being actively promoted by experimental groups across the world. In addition, nuclear theorists are making remarkable progress in the calculation of the neutrinoless double beta decay nuclear matrix elements, thus eliminating a substantial part of the theoretical uncertainties affecting the particle physics interpretation of this process. In this report, we review the main aspects of the double beta decay process and some of the most relevant experiments. The picture that emerges is one where searching for neutrinoless double beta decay is recognized to have both far-reaching theoretical implications and promising prospects for experimental observation in the near future.

J. J. Gomez-Cadenas; J. Martin-Albo; M. Mezzetto; F. Monrabal; M. Sorel

2012-01-16T23:59:59.000Z

357

Random matrix description of decaying quantum systems  

E-Print Network [OSTI]

This contribution describes a statistical model for decaying quantum systems (e.g. photo-dissociation or -ionization). It takes the interference between direct and indirect decay processes explicitely into account. The resulting expressions for the partial decay amplitudes and the corresponding cross sections may be considered a many-channel many-resonance generalization of Fano's original work on resonance lineshapes [Phys. Rev 124, 1866 (1961)]. A statistical (random matrix) model is then introduced. It allows to describe chaotic scattering systems with tunable couplings to the decay channels. We focus on the autocorrelation function of the total (photo) cross section, and we find that it depends on the same combination of parameters, as the Fano-parameter distribution. These combinations are statistical variants of the one-channel Fano parameter. It is thus possible to study Fano interference (i.e. the interference between direct and indirect decay paths) on the basis of the autocorrelation function, and thereby in the regime of overlapping resonances. It allows us, to study the Fano interference in the limit of strongly overlapping resonances, where we find a persisting effect on the level of the weak localization correction.

T. Gorin

2005-10-04T23:59:59.000Z

358
359

EFFECT OF TRITIUM AND DECAY HELIUM ON WELDMENT FRACTURE TOUGHNESS  

SciTech Connect (OSTI)

The fracture toughness data collected in this study are needed to assess the long-term effects of tritium and its decay product on tritium reservoirs. The results show that tritium and decay helium have negative effects on the fracture toughness properties of stainless steel and its weldments. The data and report from this study has been included in a material property database for use in tritium reservoir modeling efforts like the Technology Investment Program ''Lifecycle Engineering for Tritium Reservoirs''. A number of conclusions can be drawn from the data: (1) For unexposed Type 304L stainless steel, the fracture toughness of weldments was two to three times higher than the base metal toughness. (2) Tritium exposure lowered the fracture toughness properties of both base metals and weldments. This was characterized by lower J{sub Q} values and lower J-da curves. (3) Tritium-exposed-and-aged base metals and weldments had lower fracture toughness values than unexposed ones but still retained good toughness properties.

Morgan, M; Scott West, S; Michael Tosten, M

2006-09-26T23:59:59.000Z

360

Nonmesonic Weak Decay Dynamics from proton spectra of $\\Lambda$-Hypernuclei  

E-Print Network [OSTI]

A novel comparison between the data and the theory is proposed for the nonmesonic (NM) weak decay of hypernuclei. Instead of confronting the primary decay rates, as is usually done, we focus attention on the effective decay rates that are straightforwardly related with the number of emitted particles. Proton kinetic energy spectra of $^5_\\Lambda$He, $^7_\\Lambda$Li, $^9_\\Lambda$Be, $^{11}_\\Lambda$B, $^{12}_{\\Lambda}$C, $^{13}_\\Lambda$C, $^{15}_{\\Lambda}$N and $^{16}_{\\Lambda}$O, measured by FINUDA, are evaluated theoretically. The Independent Particle Shell Model (IPSM) is used as the nuclear structure framework, while the dynamics is described by the One-Meson-Exchange (OME) potential. Only for the $^{5}_{\\Lambda}$He, $^{7}_{\\Lambda}$Li, and $^{12}_{\\Lambda}$C hypernuclei is it possible to make a comparison with the data, since for the rest there is no published experimental information on number of produced hypernuclei. Considering solely the one-nucleon-induced ($1N$-NM) decay channel, the theory reproduces...

Krmpotic, Franjo

2015-01-01T23:59:59.000Z

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


361

BES Results on Charmonium Decays and Transitions  

E-Print Network [OSTI]

Results are reported based on samples of 58 million $J/\\psi$ and 14 million $\\psi(2S)$ decays obtained by the BESII experiment. Improved branching fraction measurements are determined, including branching fractions for $J/\\psi\\to\\pi^+\\pi^-\\pi^0$, $\\psi(2S)\\to \\pi^0 J/\\psi$, $\\eta J/\\psi$, $\\pi^0 \\pi^0 J/\\psi$, anything $J/\\psi$, and $\\psi(2S)\\to\\gamma\\chi_{c1},\\gamma\\chi_{c2}\\to\\gamma\\gamma\\jpsi$. Using 14 million $\\psi(2S)$ events, $f_0(980)f_0(980)$ production in $\\chi_{c0}$ decays and $K^*(892)^0\\bar K^*(892)^0$ production in $\\chi_{cJ}~(J=0,1,2)$ decays are observed for the first time, and branching ratios are determined.

Frederick A. Harris

2004-09-29T23:59:59.000Z

362

Correlations and the neutrinoless double beta decay  

SciTech Connect (OSTI)

We explore the influence of the deformation on the nuclear matrix elements of the neutrinoless double beta decay (NME), concluding that the difference in deformation -or more generally on the amount of quadrupole correlations- between parent and grand daughter nuclei quenchs strongly the decay. We discuss how varies the nuclear matrix element of {sup 76}Ge decay when the wave functions of the two nuclei involved in the transition are constrained to reproduce the experimental occupancies. In the Interacting Shell Model description the value of the NME is enhanced about 15% compared to previous calculations, whereas in the QRPA the NME's are reduced by 20%-30%, thus, the discrepancies between both approaches diminish.

Menendez, J.; Poves, A. [Departamento de Fisica Teorica, and IFT, UAM-CSIC, Universidad Autonoma de Madrid, 28049-Madrid (Spain); Caurier, E.; Nowacki, F. [IPHC, IN2P3-CNRS/Universite Louis Pasteur, 67037-Strasbourg (France)

2009-11-09T23:59:59.000Z

363

Factorization in B to V gamma Decays  

SciTech Connect (OSTI)

The factorization properties of the radiative decays B {yields} V{gamma} are analyzed at leading order in 1/mb 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 resume perturbative logarithms of the different scales in the decay process. Phenomenological implications for the B {yields} K*{gamma} branching ratio, isospin asymmetry, and CP asymmetries are discussed, with particular emphasis on possible effects from physics beyond the Standard Model.

Becher, T

2005-03-28T23:59:59.000Z

364

BaBar: Rare Charmless B Decays  

SciTech Connect (OSTI)

Three two body and two resonance decays of the B mesons have been measured using data from the BABAR detector: B{sup 0} {yields} {pi}{sup {+-}}, K{sup {-+}}, K{sup +}K{sup -}, K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} and B{sup 0} {yields} a{sub 1}{sup +}(1260){pi}{sup -}. The branching ratio and that of some intermediate resonances are presented along with the Cp asymmetry of the decay B{sup 0} {yields} K*{sup +}{pi}{sup -}.

Hutchcroft, D.; /Liverpool U.

2006-04-14T23:59:59.000Z

365

Simulated progress in double-beta decay  

SciTech Connect (OSTI)

A Monte Carlo code has been developed to accurately simulate double-beta decay measurements. Coincident gamma rays, beta spectra, and angular correlations have been added to adequately simulate a complete {sup 100}Mo nuclear decay and provide corrections to experimentally determined detector efficiencies. This code has been used to strip certain low-background spectra obtained in the Homestake gold mine in Lead, SD, for the purpose of extremely sensitive materials assay for the construction of new, large, enriched germanium detectors. Assays as low as 9 {mu}Bq/g of {sup 210}Pb in lead shielding were obtained.

Miley, H.S.; Arthur, R.J. [Pacific Northwest Lab., Richland, WA (United States); Avignone, F.T. [South Carolina Univ., Columbia, SC (United States)] [and others

1993-09-01T23:59:59.000Z

366

On the neutrinoless double ?{sup +}/EC decays  

SciTech Connect (OSTI)

The neutrinoless double positron-emission/electron-capture (0??{sup +}/EC) decays are studied for the magnitudes of the involved nuclear matrix elements (NMEs). Decays to the ground state, 0{sub gs}{sup +}, and excited 0{sup +} states are discussed. The participant many-body wave functions are evaluated in the framework of the quasiparticle random-phase approximation (QRPA). Effective, G-matrix-derived nuclear forces are used in realistic single-particle model spaces. The channels ?{sup +}?{sup +}, ?{sup +}EC, and the resonant neutrinoless double electron capture (R0?ECEC) are discussed.

Suhonen, Jouni [Department of Physics, P.O. Box 35 (YFL), FI-40014 University of Jyväskylä (Finland)

2013-12-30T23:59:59.000Z

367

SU(3) Sum Rules for Charm Decay  

E-Print Network [OSTI]

We present flavor SU(3) sum rules for $D \\to PP$ and $D \\to PV$ decay amplitudes, that are valid to second order in symmetry breaking by the strange quark mass spurion. Decay rate sum rules are also computed to this order. Particular attention is given to sum rules arising from the isospin and U-spin subgroups, the former providing sensitive tests for alternative sources of SU(3) breaking. We apply the latter together with the postulated $\\Delta U = 0$ rule for the large penguin picture to predict the ratio and difference of the direct CP asymmetries for $D \\to KK^*$ and $D \\to \\pi \\rho$.

Yuval Grossman; Dean J Robinson

2012-11-14T23:59:59.000Z

368

The double-beta decay: Theoretical challenges  

SciTech Connect (OSTI)

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

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

2012-11-20T23:59:59.000Z

369

Electromagnetic corrections to pseudoscalar decay constants  

E-Print Network [OSTI]

The effects of electromagnetic interactions on pseudoscalar decay constants are investigated. Using a compact QED and QCD action we are able to resolve differences of about 0.1 MeV. We obtain the preliminary results f_pi^0-f_pi^+/- =0.09(3) MeV and f_D^0-f_D^+/- =0.79(11) MeV for light and charmed pseudoscalar decay constants on a N_f=2 nonperturbatively improved Sheikholeslami-Wohlert ensemble.

Benjamin Glaessle; Gunnar S. Bali

2011-11-16T23:59:59.000Z

370

Detecting Double Beta Decays Using Nuclear Emulsions  

E-Print Network [OSTI]

Neutrino nature and absolute mass scale are major questions in particle physics which cannot be addressed by the present neutrino oscillation program. To answer these two questions, several neutrinoless double beta decay experiments are underway or planed for the near future. These experiments, mainly use bolometric techniques or gaseous counters coupled with scintillator detectors. The energy resolution is better in bolometric experiments but experiments coupling tracking with calorimetry have the advantage of observing the two electron tracks and remove many background sources. Here, we present a proposal of using nuclear emulsions to observe double beta decays. This technique has the advantage of precise tracking and vertexing even for low energy electrons.

Marcos Dracos

2008-05-20T23:59:59.000Z

371

The concrete theory of numbers: initial numbers and wonderful properties of numbers repunit  

E-Print Network [OSTI]

In this work initial numbers and repunit numbers have been studied. All numbers have been considered in a decimal notation. The problem of simplicity of initial numbers has been studied. Interesting properties of numbers repunit are proved: $gcd(R_a, R_b) = R_{gcd(a,b)}$; $R_{ab}/(R_aR_b)$ is an integer only if $gcd(a,b) = 1$, where $a\\geq1$, $b\\geq1$ are integers. Dividers of numbers repunit, are researched by a degree of prime number.

Boris V. Tarasov

2007-04-07T23:59:59.000Z

372

Double beta decay of ^{64,70}Zn and ^{180,186}W isotopes  

E-Print Network [OSTI]

The results of the experimental investigations of double beta processes in Zinc and Tungsten isotopes with the help of middle volume (117 g, 168 g and 699 g) low-background ZnWO_4 crystal scintillators are presented. The experiment was carried out in the low-background "DAMA/R&D" set-up at the Gran Sasso National Laboratories of the INFN (Italy) at a depth of \\approx3600 m w.e. The total measurement time exceeds ten thousand hours. New improved half-life limits on double electron capture and electron capture with positron emission in ^{64}Zn have been set: T^{2\

D. V. Poda

2011-12-05T23:59:59.000Z

373

Neutrino oscillation constraints on neutrinoless double beta decay  

E-Print Network [OSTI]

We have studied the constraints imposed by the results of neutrino oscillation experiments on the effective Majorana mass || that characterizes the contribution of Majorana neutrino masses to the matrix element of neutrinoless double-beta decay. We have shown that in a general scheme with three Majorana neutrinos and a hierarchy of neutrino masses (which can be explained by the see-saw mechanism), the results of neutrino oscillation experiments imply rather strong constraints on the parameter ||. From the results of the first reactor long-baseline experiment CHOOZ and the Bugey experiment it follows that || | > 10^{-1} eV would be a signal for a non-hierarchical neutrino mass spectrum and/or non-standard mechanisms of lepton number violation.

S. M. Bilenky; C. Giunti; C. W. Kim; M. Monteno

1997-11-20T23:59:59.000Z

374

Neutrinoless double beta decay in deformed nuclei: its implications in particle and nuclear physics .  

E-Print Network [OSTI]

??In my thesis, we calculated the Nuclear Matrix Elements (NME) for neutrinoless double beta decay (0??? decay). Neutrinoless double beta decay is a rare nuclear… (more)

Fang, DongLiang

2011-01-01T23:59:59.000Z

375

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

SciTech Connect (OSTI)

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

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

2011-12-16T23:59:59.000Z

376

Search for tau -> gamma mu: A test of lepton number conservation  

E-Print Network [OSTI]

A search for the lepton number violating decay of the tau lepton to the gammamu final state has been performed with the CLEO II detector at the Cornell e+e- storage ring CESR. In a data sample that corresponds to an ...

Ammar, Raymond G.; Ball, S.; Baringer, Philip S.; Coppage, Don; Copty, N.; Davis, Robin E. P.; Hancock, N.; Kelly, M.; Kwak, Nowhan; Lam, H.

1993-01-01T23:59:59.000Z

377

Search for rare and forbidden eta ' decays  

E-Print Network [OSTI]

We have searched for rare and forbidden decays of the eta' meson in hadronic events at the CLEO II detector. The search is conducted on 4.80 fb(-1) of e(+)e(-) collisions at 10.6 GeV center-of-mass energy at the Cornell Electron Storage Ring. We...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, X.

2000-01-01T23:59:59.000Z

378

New limits for neutrinoless tau decays  

E-Print Network [OSTI]

Neutrinoless 3-prong tau lepton decays into a charged lepton and either two charged particles or one neutral meson have been searched for using 4.79fb(-1) of data collected with the CLEO II detector at Cornell Electron Storage Ring. This analysis...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

1998-05-01T23:59:59.000Z

379

Neutrinoless double beta decay in seesaw models  

E-Print Network [OSTI]

We study the general phenomenology of neutrinoless double beta decay in seesaw models. In particular, we focus on the dependence of the neutrinoless double beta decay rate on the mass of the extra states introduced to account for the Majorana masses of light neutrinos. For this purpose, we compute the nuclear matrix elements as functions of the mass of the mediating fermions and estimate the associated uncertainties. We then discuss what can be inferred on the seesaw model parameters in the different mass regimes and clarify how the contribution of the light neutrinos should always be taken into account when deriving bounds on the extra parameters. Conversely, the extra states can also have a significant impact, cancelling the Standard Model neutrino contribution for masses lighter than the nuclear scale and leading to vanishing neutrinoless double beta decay amplitudes even if neutrinos are Majorana particles. We also discuss how seesaw models could reconcile large rates of neutrinoless double beta decay with more stringent cosmological bounds on neutrino masses.

Mattias Blennow; Enrique Fernandez-Martinez; Jacobo Lopez-Pavon; Javier Menendez

2014-05-12T23:59:59.000Z

380

Neutrinoless Double $?$-Decay: Status and Future  

E-Print Network [OSTI]

A brief summary of the status of neutrino masses, mixing and oscillations is presented. Neutrinoless double $\\beta$-decay is considered. Predictions for the effective Majorana mass are reviewed. A possible test of the calculations of nuclear matrix elements of the $0\

S. M. Bilenky

2005-09-11T23:59:59.000Z

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


381

Higgs Bosons from Top Quark Decays  

E-Print Network [OSTI]

In light of the discovery of a Standard Model (SM)-like Higgs boson ($h$) at the LHC, we investigate the top quark to Higgs boson transition $t\\rightarrow W^{*}bh$, which is the leading $t\\to h$ decay mode in the SM. We find the decay branching fraction to be $1.80\\times 10^{-9}$. In comparison, the two-body, loop-induced $t\\rightarrow ch$ transition occurs at $\\sim10^{-14}$ in the SM. We consider the consequences of gauge invariant dimension-6 operators affecting the $t\\bar{t}h$ interaction and find that the decay branching fraction may be increased by a factor of two within current constraints on the coupling parameters from collider experiments. We also extend the calculation to the CP-conserving Type I and Type II Two Higgs Doublet Models (2HDM), including both CP-even and CP-odd Higgs bosons. For neutral scalar masses at about $100$ GeV, the decay rates can be several times larger than the SM result in the allowed range of model parameters. Observation prospects at present and future colliders are briefly addressed.

Tao Han; Richard Ruiz

2014-04-28T23:59:59.000Z

382

Left-Right Symmetry: from LHC to Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

The Large Hadron Collider has a potential to probe the scale of left-right symmetry restoration and the associated lepton number violation. Moreover, it offers hope of measuring the right-handed leptonic mixing matrix. We show how this, together with constraints from lepton flavor violating processes, can be used to make predictions for neutrinoless double beta decay. We illustrate this deep connection in the case of the type-II seesaw.

Vladimir Tello; Miha Nemevsek; Fabrizio Nesti; Goran Senjanovi?; Francesco Vissani

2011-03-29T23:59:59.000Z

383

Left-Right Symmetry: From the LHC to Neutrinoless Double Beta Decay  

SciTech Connect (OSTI)

The Large Hadron Collider has the potential to probe the scale of left-right symmetry restoration and the associated lepton number violation. Moreover, it offers the hope of measuring the right-handed leptonic mixing matrix. We show how this, together with constraints from lepton flavor violating processes, can be used to make predictions for neutrinoless double beta decay. We illustrate this connection in the case of the type-II seesaw.

Tello, Vladimir [SISSA, Trieste (Italy); Nemevsek, Miha [ICTP, Trieste (Italy); Jozef Stefan Institute, Ljubljana (Slovenia); Nesti, Fabrizio [Universita di Ferrara, Ferrara (Italy); Senjanovic, Goran [ICTP, Trieste (Italy); Vissani, Francesco [LNGS, INFN, Assergi (Italy)

2011-04-15T23:59:59.000Z

384

SciTech Connect: Radioactive decay data tables  

Office of Scientific and Technical Information (OSTI)

Radioactive decay data tables Citation Details In-Document Search Title: Radioactive decay data tables You are accessing a document from the Department of Energy's (DOE) SciTech...

385

A Search for Neutrinoless Double Beta Decay of Te-130  

E-Print Network [OSTI]

Decay of Te by Adam Douglas Bryant A dissertation submitted2010 by Adam Douglas Bryant Te Abstract A Search forDecay of Te by Adam Douglas Bryant Doctor of Philosophy in

Bryant, Adam Douglas

2010-01-01T23:59:59.000Z

386

Leptonic $D_s$ decays at $B$-factories  

E-Print Network [OSTI]

We review recent measurements of leptonic $D_s$-meson decays performed by Belle and BaBar collaborations. Described measurements enable experimental extraction of the $D_s$-meson decay constant which can be compared with lattice QCD calculations.

A. Zupanc

2013-01-30T23:59:59.000Z

387

Sensitivity of CUORE to Neutrinoless Double-Beta Decay  

E-Print Network [OSTI]

Sensitivity of CUORE to Neutrinoless Double-Beta Decay b c,:Results of the Search for Neutrinoless D o u b l e - B e t ah e i n a , Evidence for neutrinoless double beta decay, M o

Alessandria, F.

2013-01-01T23:59:59.000Z

388

A Search for Neutrinoless Double Beta Decay of Te-130  

E-Print Network [OSTI]

Bolometric experiments for neutrinoless double beta 3.2.1A Search for Neutrinoless Double Beta Decay of Te by AdamSpring 2010 A Search for Neutrinoless Double Beta Decay of

Bryant, Adam Douglas

2010-01-01T23:59:59.000Z

389

Demolishing Decay at the Hanford Site | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Demolishing Decay at the Hanford Site Demolishing Decay at the Hanford Site February 22, 2011 - 5:44pm Addthis The stacks and support structures of the 284 West Power House at the...

390

Data Compression with Prime Numbers  

E-Print Network [OSTI]

A compression algorithm is presented that uses the set of prime numbers. Sequences of numbers are correlated with the prime numbers, and labeled with the integers. The algorithm can be iterated on data sets, generating factors of doubles on the compression.

Gordon Chalmers

2005-11-16T23:59:59.000Z

391

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

E-Print Network [OSTI]

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

U. Raha; F. Myhrer; K. Kubodera

2014-05-06T23:59:59.000Z

392

Hybrid meson decay from lattice QCD  

E-Print Network [OSTI]

Besides the conventional hadrons containing valence quarks and valence antiquarks, quantum chromodynamics (QCD) suggests the existence of the hybrid hadrons containing valence gluons in addition to the quarks and antiquarks, and some experiments may have found some. A decisive experimental confirmation of its existence, however, is still needed. At present, lattice simulations have offered the practicable ways of theoretically guiding us to search for the hybrid states. In this dissertation, we study the spectroscopy and the decay rate of the heavy hybrid mesons made of a heavy $b$ quark, a heavy $\\bar b$ antiquark, and a gluon ($b\\bar{b}g$) to selected channels, and use lattice methods to extract the transition matrix elements in full QCD. We are particular interested in the spin-exotic hybrid mesons. For sufficiently heavy quarks (e.g., $b$ quark), we use the leading Born-Oppenheimer (LBO) approximation to calculate the static potential energy at all $b\\bar{b}$ separations. Then, by solving the Schr\\"odinger equation with this potential, we reconstruct the motion of the heavy quarks. In a similar way we can determine decay rates. In this dissertation, we use the numerical lattice method to calculate the mass of the $f_0$ meson at a single lattice spacing and light quark mass, namely, $m_{f_0} = (768 \\pm 136)$ MeV. Most of all we consider the decay channels involving the production of a scalar meson. We obtain the partial decay rate ($\\Gamma$) for the channel $ H \\rightarrow \\chi_b + \\pi + \\pi $, namely, $ \\Gamma = 3.62(98)$ MeV. All of our results are consistent with those of other researchers. Knowledge of the masses and the decay rates should help us considerably in experimental searches for the hybrid mesons.

Ziwen Fu

2011-03-08T23:59:59.000Z

393

The nuclear radius from alpha decay (*) Centre d'Etudes Nuclaires, Le Haut Vigneau, 33170 Gradignan, France  

E-Print Network [OSTI]

] have shown that the nuclear radius is not so simple and the law A 1/3 is only an approximationL-181 The nuclear radius from alpha decay (*) L. Marquez Centre d'Etudes Nucléaires, Le Haut structures qui sont en corrélation. Abstract. 2014 Nuclear radii for mass numbers between A = 140 and 252

Boyer, Edmond

394

/ Search for Neutrinoless Double Beta Decay with CUORE  

E-Print Network [OSTI]

neutrinoless double beta decay (??0?) in 130 Te and other rare processes. The observation of ??0? would

Elena Ferri

395

Search for neutrinoless decays of the tau lepton  

E-Print Network [OSTI]

. The upper limits obtained for 22 decay branching fractions are several times more stringent than those set previously....

Ammar, Raymond G.; Ball, S.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Copty, N.; Davis, Robin E. P.; Hancock, N.; Kelly, M.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Lam, H.

1994-10-01T23:59:59.000Z

396

The Neutrinoless Double Beta Decay: The Case for Germanium Detectors  

E-Print Network [OSTI]

An overview of the current status of Neutrinoless Double Beta Decay is presented, emphasizing on the case of Germanium Detectors.

A. Morales; J. Morales

2002-11-21T23:59:59.000Z

397

Search for neutrinoless double beta decay with NEMO 3 experiment  

E-Print Network [OSTI]

NEMO 3 experiment is designed to search for neutrinoless double beta decay. It is located in the Modane Underground Laboratory (LSM) and has been taking data since February 2003. The half- lives of two neutrino beta decay have been measured for seven isotopes. No evidence of neutrinoless double beta decay has been found. The limits on both the half-lives of the neutrinoless double beta decay and the corresponding Majorana effective masses are derived

Zornitza Daraktchieva

2009-01-18T23:59:59.000Z

398

Threshold resummed spectra in semi-inclusive B decays  

E-Print Network [OSTI]

I discuss some aspects of the universality of soft gluon dynamics in semileptonic and radiative decays at the threshold region.

Giulia Ricciardi

2006-07-05T23:59:59.000Z

399

DECAY CONSTANTS OF CHARGED PSEUDO-SCALAR MESONS  

E-Print Network [OSTI]

- and D+ s decays, the existence of a charged Higgs boson (or any other charged object beyond the Standard

400

Hadronic B_u and B_d decays  

E-Print Network [OSTI]

I present latest measurements from the B factories of branching fractions for B meson decays to hadronic two- and three-body final states. These include the rate of doubly Cabibbo-suppressed charge states of charmed mesons in two-body decays, charmed baryons and other structure seen in baryonic B decays, and charmless mesonic two-body decays in comparison with estimates from theory.

W. T. Ford

2008-10-02T23:59:59.000Z

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


401

Search for Invisibly Decaying Higgs Bosons with Large Decay Width Using the OPAL Detector at LEP  

E-Print Network [OSTI]

This paper describes a topological search for an invisibly decaying Higgs boson,H, produced via the Bjorken process (e+e- -> HZ). The analysis is based on data recorded using the OPAL detector at LEP at centre-of-mass energies from 183 to 209 GeV corresponding to a total integrated luminosity of 629pb-1. In the analysis only hadronic decays of the Z boson are considered. A scan over Higgs boson masses from 1 to 120 GeV and decay widths from 1 to 3000 GeV revealed no indication for a signal in the data. From a likelihood ratio of expected signal and Standard Model background we determine upper limits on cross-section times branching ratio to an invisible final state. For moderate Higgs boson decay widths, these range from about 0.07pb Mh = 60GeV) to 0.57pb (Mh = 114GeV). For decay widths above 200GeV the upper limits are of the order of 0.15pb. The results can be interpreted in general scenarios predicting a large invisible decay width of the Higgs boson. As an example we interpret the results in the so-called...

Abbiendi, G; Ĺkesson, P F; Alexander, G; Anagnostou, G; Anderson, K J; Asai, S; Axen, D; Bailey, I; Barberio, E; Barillari, T; Barlow, R J; Batley, J Richard; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, Siegfried; Biebel, O; Boeriu, O; Bock, P; Boutemeur, M; Braibant, S; Brown, R M; Burckhart, H J; Campana, S; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Ciocca, C; Csilling, A; Cuani, M; Dado, S; de Roeck, A; De Wolf, E A; Desch, K; Dienes, B; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, F; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Gagnon, P; Gary, J W; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Gross, E; Grunhaus, J; Gruwé, M; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harel, A; Hauschild, M; Hawkes, C M; Hawkings, R; Herten, G; Heuer, R D; Hill, J C; Horváth, D; Igo-Kemenes, P; Ishii, K; Jeremie, H; Jovanovic, P; Junk, T R; Kanzaki, J; Karlen, D; Kawagoe, K; Kawamoto, T; Keeler, R K; Kellogg, R G; Kennedy, B W; Kluth, S; Kobayashi, T; Kobel, M; Komamiya, S; Kramer, T; Krasznahorkay, A; Krieger, P; Von Krogh, J; Kühl, T; Kupper, M; Laerty, G D; Landsman, H; Lanske, D; Lellouch, D; Letts, J; Levinson, L; Lillich, J; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, A; Ludwig, J; Mader, W; Marcellini, S; Martin, A J; Mashimo, T; Mättig, P; McKenna, J; McPherson, R A; Meijers, F; Menges, W; Merritt, F S; Mes, H; Meyer, N; Michelini, A; Mihara, S; Mikenberg, G; Miller, D J; Mohr, W; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; Nisius, R; O'Neale, S W; Oh, A; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Pilcher, J E; Pinfold, J L; Plane, D E; Pooth, O; Przybycien, M B; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Roney, J M; Rossi, A M; Rozen, Y; Runge, K; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Schar-Hansen, P; Schieck, J; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Seuster, R; Shears, T G; Shen, B C; Sherwood, P; Skuja, A; Smith, A M; Sobie, R J; Söldner-Rembold, S; Spanó, F; Stahl, A; Strom, D; Ströhmer, R; Tarem, S; Tasevsky, M; Teuscher, R; Thomson, M A; Torrence, E; Toya, D; Tran, P; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vollmer, C F; Vannerem, P; Vertesi, R; Verzocchi, M; Voss, H; Vossebeld, Joost Herman; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Zer-Zion, D; Zivkovic, L

2007-01-01T23:59:59.000Z

402

Double Beta Decay Experiments Department of Physics and Astronomy  

E-Print Network [OSTI]

1 Double Beta Decay Experiments A. Piepkea a Department of Physics and Astronomy University. The experimen- tal investigation of the nuclear double beta decay is one of the key techniques for solving, such as the evaluation of the beta spec- tra near their endpoint, or neutrinoless double beta decay. The latter technique

Piepke, Andreas G.

403

Measurement of CP Violation in B[0 over s] ? ?? decays  

E-Print Network [OSTI]

A measurement of the decay time-dependent CP-violating asymmetry in B[0 over s] ? ?? decays is presented, along with measurements of the T-odd triple-product asymmetries. In this decay channel, the CP-violating weak phase ...

Counts, Ian Thomas Hunt

404

Imperfect World of $\\beta\\beta$-decay Nuclear Data Sets  

E-Print Network [OSTI]

The precision of double-beta ($\\beta\\beta$) decay experimental half lives and their uncertainties is reanalyzed. The method of Benford's distributions has been applied to nuclear reaction, structure and decay data sets. First-digit distribution trend for $\\beta\\beta$-decay T$_{1/2}^{2\

Pritychenko, B

2015-01-01T23:59:59.000Z

405

Sensitivity of CUORE to Neutrinoless Double-Beta Decay  

E-Print Network [OSTI]

of CUORE to Neutrinoless Double-Beta Decay b c,:L d e f F .s t results on neutrinoless double beta decay of T e w i t hthe study of neutrinoless double beta decay, J . C r y s t .

Alessandria, F.

2013-01-01T23:59:59.000Z

406

The Majorana Neutrinoless Double-Beta Decay Experiment  

E-Print Network [OSTI]

The Majorana Neutrinoless Double-Beta Decay Experiment Pre-conceptual Design Proposal November 22 Motivation for Neutrinoless Double-Beta Decay Experiments . . . . . . . . . 4 2.1.1 Community Guidance Neutrinoless Double-Beta Decay Results . . . . . . . . . . . . . . . . . . . . 12 2.5 Next

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

407

Publisher's note: Branching ratios for the beta decay of Na-21 (vol 74, pg 015501, 2006)  

E-Print Network [OSTI]

PHYSICAL REVIEW C 74, 029901(E) (2006) Publisher?s Note: Branching ratios for the ? decay of 21Na [Phys. Rev. C 74, 015501 (2006)] V. E. Iacob, J. C. Hardy, C. A. Gagliardi, J. Goodwin, N. Nica, H. I. Park, G. Tabacaru, L. Trache, R. E. Tribble..., Y. Zhai, and I. S. Towner (Received 31 July 2006; published 11 August 2006) DOI: 10.1103/PhysRevC.74.029901 PACS number(s): 27.30.+t, 23.40.?s, 99.10.Fg This paper was published online on 14 July 2006 with formatting errors in Eqs. (7) and (9...

Iacob, V. E.; Hardy, John C.; Gagliardi, Carl A.; Goodwin, J.; Nica, N.; Park, H. I.; Tabacaru, G.; Trache, L.; Tribble, Robert E.; Zhai, Y.; Towner, I. S.

2006-01-01T23:59:59.000Z

408

Subatomic (Particle) Physics in Canada The Canadian particle physics community  

E-Print Network [OSTI]

with a half-life of about 1.8 Ă? 1021y. The neutrinoless double beta decay Ge76 32 Se76 34e-e- would violate

409

Unique first-forbidden $?$-decay rates for neutron-rich nickel isotopes in stellar environment  

E-Print Network [OSTI]

In astrophysical environments, allowed Gamow-Teller (GT) transitions are important, particularly for $\\beta$-decay rates in presupernova evolution of massive stars, since they contribute to the fine-tuning of the lepton-to-baryon content of the stellar matter prior to and during the collapse of a heavy star. In environments where GT transitions are unfavored, first-forbidden transitions become important especially in medium heavy and heavy nuclei. Particularly in case of neutron-rich nuclei, first-forbidden transitions are favored primarily due to the phase-space amplification for these transitions. In this work the total $\\beta$-decay half-lives and the unique first-forbidden(U1F) $\\beta$-decay rates for a number of neutron-rich nickel isotopes, $^{72-78}$Ni, are calculated using the proton-neutron quasi-particle random phase approximation (pn-QRPA) theory in stellar environment for the first time. For the calculation of the $\\beta$-decay half-lives both allowed and unique first-forbidden transitions were considered. Comparison of the total half-lives is made with measurements and other theoretical calculations where it was found that the pn-QRPA results are in better agreement with experiments and at the same time are suggestive of inclusion of rank 0 and rank 1 operators in first-forbidden rates for still better results.

Jameel-Un Nabi; Sabin Stoica

2014-05-31T23:59:59.000Z

410

Short-range mechanisms of neutrinoless double beta decay at the LHC  

E-Print Network [OSTI]

Lepton number violation (LNV) mediated by short range operators can manifest itself in both neutrinoless double beta decay and in processes with same sign dilepton final states at the LHC. We derive limits from existing LHC data at $\\sqrt{s}=8$ TeV and compare the discovery potential of the forthcoming $\\sqrt{s}=14$ TeV phase of the LHC with the sensitivity of current and future neutrinoless double beta decay experiments, assuming the short-range part of the decay amplitude dominates. We focus on the first of two possible topologies triggered by one fermion and two bosons in the intermediate state. In all cases, except for the pure leptoquark mechanism, the LHC will be more sensitive than neutrinoless double beta decay in the future. In addition, we propose to search for a charge asymmetry in the final state leptons and to use different invariant mass peaks as a possibility to discriminate the various possible mechanisms for LNV signals at the LHC.

J. C. Helo; M. Hirsch; H. Päs; S. G. Kovalenko

2013-07-18T23:59:59.000Z

411

New features in the stability and fission decay of superheavy Thorium isotopes  

E-Print Network [OSTI]

Superheavy isotopes are highly neutron rich nuclei in the vicinity of neutron drip-line, stabilized by shell effect against the instability due to repulsive component of nuclear force, analogous to superheavy elements similarly stabilized against Coulomb instability. Here we discuss the stability and fission decay properties of such nuclei in the $^{254}$Th region and show that they are stable against $\\alpha$ and fission decay and have $\\beta$-decay life time of several tens of seconds. In particular, the $^{254}$Th nucleus has a low fission barrier and unusally large barrier width. This makes it an ideal thermally fissile nucleus, if formed by means of a thermal neutron, like other known nuclei such as $^{233}$U, $^{235}$U, $^{239}$Pu in this actinide region. It shows a new mode of fast fission decay, which may be termed as multifragmentation fission, in which in addition to two heavy fragments large number of scission neutrons are simultaneously produced. Its likely synthesis during the r-process nucleosynthesis will have important bearing on steller evolution, and here in the laboratory, it has great potential in energy production.

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

2006-04-12T23:59:59.000Z

412

The Isospin Model prediction for multi-pion tau decays  

E-Print Network [OSTI]

The predictions of an isospin model are compared with the branching ratios of the 5 and 6 pion decays of the tau lepton. In both cases, the isospin model suggests that the tau favours decays in which there is an omega resonance. Recent measurements of such tau decays confirm this hypothesis. If the decay of the tau to 7 pions also proceeds through an intermediate omega, then the isospin model predicts that the branching ratio of the tau to seven charged pions should be small when compared with other 7 pion decays. New limits on this mode appear to support this argument.

Randall J. Sobie

1998-10-19T23:59:59.000Z

413

The nuclear matrix elements for neutrinoless double beta decay  

SciTech Connect (OSTI)

The status of calculation of the neutrinoless double beta decay (0{nu}{beta}{beta}-decay) nuclear matrix elements (NME's) is reviewed. The spread of published values of NME's is discussed. The main attention is paid to the recent progress achieved in the evaluation of the 0{nu}{beta}{beta}-decay NME's in the framework of the quasiparticle random phase approximation (QRPA). The obtained results are compared with those of the nuclear shell model. The problem of reliable determination of the 0{nu}{beta}{beta}-decay NME's is addressed. The uncertainty in NME's are analyzed and further progress in calculation of the 0{nu}{beta}{beta}-decay NME's is outlined.

Simkovic, Fedor [Department of Nuclear Physics and Biophysics, Comenius University, Mlynska dolina, SK-84248 Bratislava (Slovakia)

2007-10-12T23:59:59.000Z

414

Searches for very rare decays of kaons  

SciTech Connect (OSTI)

The physics motivation for searches for very rare kaon decays, either forbidden or suppressed within the Standard Model, is briefly discussed. Simple arguments conclude that such searches probe possible new forces at a 200 TeV mass scale or constitute a precision test of the electroweak model. The examples of such process are decays of K{sub L}{sup 0} {yields} {mu} {sup {+-}}e{sup -+}, K{sup +} {yields} {pi}{sup +} {mu}{sup +} e{sup -}, K{sub L}{sup 0} {yields} {mu}{sup +} {mu}{sup -}, and K{sup +} {yields} {pi} {yields} {pi}{sup +}{nu}{bar {nu}}. We present the current experimental status and describe the new efforts to reach sensitivities down to one part in 10{sup 12}. The discussion is focused on the experimental program at the Alternating Gradient Synchrotron at Brookhaven National Laboratory, where intense beams make such studies possible.

Lang, K. [Univ. of Texas, Austin, TX (United States)

1997-01-01T23:59:59.000Z

415

Volume 54, Number 10, 2000 APPLIED SPECTROSCOPY 14430003-7028 / 00 / 5410-1443$2.00 / 0 q 2000 Society for Applied Spectroscopy  

E-Print Network [OSTI]

, from a - counting and from the more recent g -spectrometry method, has been made for marine sediment and investigation of the harbor dynamics and history of pollution. Index Headings: Analytical methods; Gamma-ray spectrometry; Al- pha spectrometry; Marine sediment pollution. INTRODUCTION Pb-210 (half-life 22.3 years) has

Yu, K.N.

416

Compendium of Experimental Cetane Numbers  

SciTech Connect (OSTI)

This report is an updated version of the 2004 Compendium of Experimental Cetane Number Data and presents a compilation of measured cetane numbers for pure chemical compounds. It includes all available single compound cetane number data found in the scientific literature up until March 2014 as well as a number of unpublished values, most measured over the past decade at the National Renewable Energy Laboratory. This Compendium contains cetane values for 389 pure compounds, including 189 hydrocarbons and 201 oxygenates. More than 250 individual measurements are new to this version of the Compendium. For many compounds, numerous measurements are included, often collected by different researchers using different methods. Cetane number is a relative ranking of a fuel's autoignition characteristics for use in compression ignition engines; it is based on the amount of time between fuel injection and ignition, also known as ignition delay. The cetane number is typically measured either in a single-cylinder engine or a constant volume combustion chamber. Values in the previous Compendium derived from octane numbers have been removed, and replaced with a brief analysis of the correlation between cetane numbers and octane numbers. The discussion on the accuracy and precision of the most commonly used methods for measuring cetane has been expanded and the data has been annotated extensively to provide additional information that will help the reader judge the relative reliability of individual results.

Yanowitz, J.; Ratcliff, M. A.; McCormick, R. L.; Taylor, J. D.; Murphy, M. J.

2014-08-01T23:59:59.000Z

417

Neutrinoless Double Beta Decay in Particle Physics  

E-Print Network [OSTI]

Neutrinoless double beta decay is a process of fundamental importance for particle physics. It can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). We review its dependence on the neutrino parameters, its complementarity to other observables sensitive to neutrino mass, and emphasize its ability to distinguish different neutrino mass models. Then we discuss mechanisms different from light Majorana neutrino exchange, and show what can be learned from those and how they could be tested.

Werner Rodejohann

2010-11-22T23:59:59.000Z

418

Electroweak Corrections to the Top Quark Decay  

E-Print Network [OSTI]

We have calculated the one-loop electroweak corrections to the decay t-> bW+, including the counterterm for the CKM matrix elements V(tb). Previous calculations used an incorrect delta V(tb) that led to a gauge dependent amplitude. However, since the contribution stemming from delta V(tb) is small, those calculations only underestimate the width by roughly one part in 10^5.

S. M. Oliveira; L. Bruecher; R. Santos; A. Barroso

2001-01-18T23:59:59.000Z

419

Analysis of exponential decay curves of mixtures  

E-Print Network [OSTI]

. Tommy Cobb who kept me on the straight and narrow during those first few trying weeks, and to Richard "Hoot" Gibson for his help with LP/90. TABLE OF CONTENTS Acknowledgments List of Tables CHAPTER Page lil Introduction III IV Linear... thesis written by Lt, Col. Tommy Cobb at Texas A&M University in the spring of 1966. When most substances are irradiated, radioactive isotopes are created which give off radioactive emissions according to the exponen- tial decay formula. The half...

McGaughey, Robert Lee

1967-01-01T23:59:59.000Z

420

Decaying Dark Matter and the Deficit of Dwarf Haloes  

E-Print Network [OSTI]

The hierarchical clustering inherent in Lambda-CDM cosmology seems to produce many of the observed characteristics of large-scale structure. But some glaring problems still remain, including the over-prediction (by a factor 10) of the number of dwarf galaxies within the virialized population of the local group. Several secondary effects have already been proposed to resolve this problem. It is still not clear, however, whether the principal solution rests with astrophysical processes, such as early feedback from supernovae, or possibly with as yet undetermined properties of the dark matter itself. In this paper, we carry out a detailed calculation of the dwarf halo evolution incorporating the effects of a hypothesized dark-matter decay, D -> D'+l, where D is the unstable particle, D' is the more massive daughter particle and l is the other, lighter (or possibly massless) daughter particle. This process preferentially heats the smaller haloes, expanding them during their evolution and reducing their present-day circular velocity. We find that this mechanism can account very well for the factor 4 deficit in the observed number of systems with velocity 10--20 km/s compared to those predicted by the numerical simulations, if dm/m_D' ~ 5-7 x 10^{-5}, where dm is the mass difference between the initial and final states. The corresponding lifetime tau cannot be longer than ~30 Gyr, but may be as short as just a few Gyr.

Majd Abdelqader; Fulvio Melia

2008-06-03T23:59:59.000Z

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421

Number  

Office of Legacy Management (LM)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment ofof EnergyYou$0.C. 20545*.MSE Cores" _ ,' ,:.'' , /v-i 2 -i 3

422

Double beta decays of {sup 106}Cd  

SciTech Connect (OSTI)

The two-neutrino (2{nu}2{beta}) and neutrinoless (0{nu}2{beta}) double beta decays of {sup 106}Cd are studied for the transitions to the ground state 0{sub gs}{sup +} and 0{sup +} and 2{sup +} excited states in {sup 106}Pd by using realistic many-body wave functions calculated in the framework of the quasiparticle random-phase approximation. Effective, G-matrix-derived nuclear forces are used in realistic single-particle model spaces. All the possible channels, {beta}{sup +}{beta}{sup +}, {beta}{sup +}EC, and ECEC, are discussed for both the 2{nu}2{beta} and 0{nu}2{beta} decays. The associated half-lives are computed and particular attention is devoted to the study of the detectability of the resonant neutrinoless double electron capture (R0{nu}ECEC) process in {sup 106}Cd. The calculations of the present article constitute the thus far most complete and up-to-date investigation of the double-beta-decay properties of {sup 106}Cd.

Suhonen, Jouni [Department of Physics, P.O. Box 35 (YFL), FI-40014 University of Jyvaeskylae (Finland)

2011-12-16T23:59:59.000Z

423

A background free double beta decay experiment  

E-Print Network [OSTI]

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

Ioannis Giomataris

2010-12-20T23:59:59.000Z

424

A background free double beta decay experiment  

E-Print Network [OSTI]

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

Giomataris, Ioannis

2010-01-01T23:59:59.000Z

425

Age-dependent decay in the landscape  

E-Print Network [OSTI]

The picture of the "multiverse" arising in diverse cosmological scenarios involves transitions between metastable vacuum states. It was pointed out by Krauss and Dent that the transition rates decrease at very late times, leading to a dependence of the transition probability between vacua on the age of each vacuum region. I investigate the implications of this non-Markovian, age-dependent decay on the global structure of the spacetime in landscape scenarios. I show that the fractal dimension of the eternally inflating domain is precisely equal to 3, instead of being slightly below 3 in scenarios with purely Markovian, age-independent decay. I develop a complete description of a non-Markovian landscape in terms of a nonlocal master equation. Using this description I demonstrate by an explicit calculation that, under some technical assumptions about the landscape, the probabilistic predictions of our position in the landscape are essentially unchanged, regardless of the measure used to extract these predictions. I briefly discuss the physical plausibility of realizing non-Markovian vacuum decay in cosmology in view of the possible decoherence of the metastable quantum state.

Sergei Winitzki

2007-12-14T23:59:59.000Z

426

Delayed Nickel Decay in Gamma Ray Bursts  

E-Print Network [OSTI]

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

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

2002-05-19T23:59:59.000Z

427

Measurement of the half-life of (198)Au in a nonmetal: High-precision measurement shows no host-material dependence  

E-Print Network [OSTI]

://www.ortec-online.com/Solutions/multichannel-analyzers. aspx]. [8] R. Jenkins, R. W. Gould, and D. Gedcke, Quantitative X-ray Spectrometry (Dekker, New York, 1981), p. 266. [9] D. Radford (private communication) [http://radware.phy. ornl.gov/main.html]. [10] R. Brun and F. Rademakers, Nucl. Instrum...

Goodwin, J. R.; Nica, N.; Iacob, V. E.; Dibidad, A.; Hardy, John C.

2010-01-01T23:59:59.000Z

428

THE FIRST ISOLATION OF AMERICIUM IN THE FORM OF PURE COMPOUNDS - THE SPECIFIC ALPHA-ACTIVITY AND HALF-LIFE OF Am241  

E-Print Network [OSTI]

eng-48 THE FIRST ISOLATION QF AMERICIUM IN THE FORM OF PURECalifornia July 20, 1950 l Americium was discovered inof the chemistry of americium were carried out by its

Cunningham, B.B.

2011-01-01T23:59:59.000Z

429

Half-lives of Double $?^+$-decay with Two Neutrinos  

E-Print Network [OSTI]

Nuclear double $\\beta ^-$-decays with two neutrinos were observed for many years and a systematic law describing the relation between their half-lives and decay energies was also proposed recently [Phys. Rev. C89, 064603 (2014)]. However, double $\\beta ^+$-decay ($\\beta ^+\\beta^+)$ with emission of both two positrons and two neutrinos has not been observed up to date. In this article, we perform a systematic analysis on the candidates of double $\\beta ^+$-decay, based on the 2012 nuclear mass table. Eight nuclei are found to be the good candidates for double $\\beta ^+$-decay and their half-lives are predicted according to the generalization of the systematic law to double $\\beta ^+$-decay. As far as we know, there is no theoretical result on double $\\beta ^+$-decay of nucleus $^{154}Dy$ and our result is the first prediction on this nucleus. This is also the first complete research on eight double $\\beta ^+$-decay candidates based on the available data of nuclear masses. It is expected that the calculated half-lives of double $\\beta ^+$-decay in this article will be useful for future experimental search of double $\\beta ^+$-decay.

Yuejiao Ren; Zhongzhou Ren

2015-01-07T23:59:59.000Z

430

Electron-capture delayed fission properties of {sup 242}Es  

SciTech Connect (OSTI)

Electron-capture delayed fission of {sup 242}Es produced via the {sup 233}U({sup 14}N,5n){sup 242}Es reaction at 87 MeV (on target) was observed to decay with a half-life of 11{+-}3 s, consistent with the reported {alpha}-decay half-life of {sup 242}Es of 16{sub -4}{sup +6} s. The mass-yield distribution of the fission fragments is highly asymmetric. The average pre-neutron emission total kinetic energy of the fragments was measured to be 183{+-}18 MeV. Based on the ratio of the measured number of fission events to the measured number of {alpha} decays from the electron-capture daughter {sup 242}Cf (100% {alpha} branch), the probability of delayed fission was determined to be 0.006{+-}0.002. This value for the delayed fission probability fits the experimental trend of increasing delayed fission probability with increasing Q value for electron capture. (c) 2000 The American Physical Society.

Shaughnessy, D. A. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Chemistry Department, University of California, Berkeley, California 94720 (United States); Adams, J. L. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Gregorich, K. E. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Lane, M. R. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Laue, C. A. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Lee, D. M. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); McGrath, C. A. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Patin, J. B. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Strellis, D. A. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Sylwester, E. R. [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States) [Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 70-319, Berkeley, California 94720 (United States); Chemistry Department, University of California, Berkeley, California 94720 (United States)] (and others)

2000-04-01T23:59:59.000Z

431

Analog simulations of josephson junction in a microwave field. Devil's staircase, fractal dimension, and decay constants  

SciTech Connect (OSTI)

The RSJ model of the Josephson junction in the presence of a microwave field is studied using an analog computer, with special attention to the behavior of this system near or at the critical line, where the set of substeps forms a complete devil's staircase on the I-V characteristic. A value of fractal dimension D = 0.868 +/- 0.002 is determined from 240 substeps between the winding numbers W = 0 and W = 1. Four values of decay constants are determined. The results agree very well with the prediction obtained from the one-dimensional circle map. A self-similarity graph is shown confirming that the staircase is very near the critical line. Results confirm the universal and global character of D and decay constants on the critical line, as was suggested by Jensen et al.

Kuznik, V.; Odehnal, M.

1986-12-01T23:59:59.000Z

432

Energy Density Functional Study of Nuclear Matrix Elements for Neutrinoless {beta}{beta} Decay  

SciTech Connect (OSTI)

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

Rodriguez, Tomas R. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64259 Darmstadt (Germany); Departamento de Fisica Teorica, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); CEA, Irfu, SPhN, Centre de Saclay, F-911191 Gif-sur-Yvette (France); Martinez-Pinedo, Gabriel [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64259 Darmstadt (Germany)

2010-12-17T23:59:59.000Z

433

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

E-Print Network [OSTI]

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

Tomás R. Rodríguez; G. Martinez-Pinedo

2010-08-31T23:59:59.000Z

434

LSP Squark Decays at the LHC and the Neutrino Mass Hierarchy  

E-Print Network [OSTI]

The existence of R-parity in supersymmetric models can be naturally explained as being a discrete subgroup of gauged baryon minus lepton number (B-L). The most minimal supersymmetric B-L model triggers spontaneous R-parity violation, while remaining consistent with proton stability. This model is well-motivated by string theory and makes several interesting, testable predictions. Furthermore, R-parity violation contributes to neutrino masses, thereby connecting the neutrino sector to the decay of the lightest supersymmetric particle (LSP). This paper analyzes the decays of third generation squark LSPs into a quark and a lepton. In certain cases, the branching ratios into charged leptons reveal information about the neutrino mass hierarchy, a current goal of experimental neutrino physics, as well as the $\\theta_{23}$ neutrino mixing angle. Furthermore, optimization of leptoquark searches for this scenario is discussed. Using currently available data, the lower bounds on the third generation squarks are computed.

Zachary Marshall; Burt A. Ovrut; Austin Purves; Sogee Spinner

2014-08-05T23:59:59.000Z

435

RNG: A Practitioner's Overview Random Number Generation  

E-Print Network [OSTI]

RNG: A Practitioner's Overview Random Number Generation A Practitioner's Overview Prof. Michael and Monte Carlo Methods Pseudorandom number generation Types of pseudorandom numbers Properties of these pseudorandom numbers Parallelization of pseudorandom number generators New directions for SPRNG Quasirandom

Mascagni, Michael

436

Motion at low Reynolds number  

E-Print Network [OSTI]

The work described in this thesis centers on inertialess motion at low Reynolds numbers at the crossroad between biofluids and microfluids. Here we address questions regarding locomotion of micro-swimmers, transport of ...

Tam, Daniel See Wai, 1980-

2008-01-01T23:59:59.000Z

437

Departmental Business Instrument Numbering System  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

To prescribe procedures for assigning identifying numbers to all Department of Energy (DOE), including the National Nuclear Security Administration, business instruments. Cancels DOE 1331.2B. Canceled by DOE O 540.1A.

2000-12-05T23:59:59.000Z

438

Departmental Business Instrument Numbering System  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

The Order prescribes the procedures for assigning identifying numbers to all Department of Energy (DOE) and National Nuclear Security Administration (NNSA) business instruments. Cancels DOE O 540.1. Canceled by DOE O 540.1B.

2005-01-27T23:59:59.000Z

439

NONIDEAL MAGNETOHYDRODYNAMIC TURBULENT DECAY IN MOLECULAR CLOUDS  

SciTech Connect (OSTI)

It is well known that nonideal magnetohydrodynamic (MHD) effects are important in the dynamics of molecular clouds: both ambipolar diffusion and possibly the Hall effect have been identified as significant. We present the results of a suite of simulations with a resolution of 512{sup 3} of turbulent decay in molecular clouds, incorporating a simplified form of both ambipolar diffusion and the Hall effect simultaneously. The initial velocity field in the turbulence is varied from being super-Alfvenic and hypersonic, through to trans-Alfvenic but still supersonic. We find that ambipolar diffusion increases the rate of decay of the turbulence increasing the decay from t {sup -1.25} to t {sup -1.4}. The Hall effect has virtually no impact in this regard. The power spectra of density, velocity, and the magnetic field are all affected by the nonideal terms, being steepened significantly when compared with ideal MHD turbulence with exponents. The density power-spectra components change from {approx}1.4 to {approx}2.1 for the ideal and nonideal simulations respectively, and power spectra of the other variables all show similar modifications when nonideal effects are considered. Again, the dominant source of these changes is ambipolar diffusion rather than the Hall effect. There is also a decoupling between the velocity field and the magnetic field at short length scales. The Hall effect leads to enhanced magnetic reconnection, and hence less power, at short length scales. The dependence of the velocity dispersion on the characteristic length scale is studied and found not to be power law in nature.

Downes, T. P. [School of Cosmic Physics, Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2 (Ireland); O'Sullivan, S. [National Centre for Plasma Science and Technology, Dublin City University, Glasnevin, Dublin 9 (Ireland)], E-mail: turlough.downes@dcu.ie

2009-08-20T23:59:59.000Z

440

Fission-product-decay characteristics. Master's thesis  

SciTech Connect (OSTI)

This theses determined fission-product decay characteristics , including the total activity, the gamma-ray emission rate (GER) and gamma-ray energy spectra. The activity and GER decay were compared to Way and Wigner's t(exp(-1.2)) approximation, and the effects the spectra, activity, and GER have on the Source Normalization Constant (K) were examined. Most of the fission-product data were obtained from DKPOWR, and were compared with data obtained from ORIGIN2. Since the gamma rays are of primary concern in fallout studies, the GER is used instead of activity. The ratio of GER to activity changes significantly with time. Results of this study calculate a GER of 590 x 10/sup 16/ gamma rays/second per kT of fission yield from U-235 fuel and a K of 7059 R/Hr/(kT/sq.km.). The calculation of K includes the contribution from scattered photons. The GER result is 11% higher than reference values, while the K is within 2% of the current value in Glasstone and Dolan's The Effects of Nuclear Weapons. The Ks for Pu-239 and U-238 were within 5% of the U-235 results. The wax-wigners t(exp(-1.2)) approximation differs from time dependent GER and K up to 85% for times less than 6 months. The approximation is not valid for the GER or K at times greater than 6 months. The approximation is within about 45%, for the activity from fission-product decay to at least 5 years. A more accurate measure of exposure requires a numerical integration of the time dependent GER and Source Normalization Constant.

Millage, K.K.

1989-03-01T23:59:59.000Z

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


441

Inclusive B decays from resummed perturbation theory.  

E-Print Network [OSTI]

ar X iv :h ep -p h/ 07 03 03 6v 1 4 M ar 2 00 7 Inclusive B decays from resummed perturbation theory Einan Gardi Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK and Department of Applied Mathematics... for the experimentally–relevant branching fractions can be derived from resummed perturbation theory and explain the way in which the resummation further provides guidance in parametrizing non-perturbative Fermi–motion effects. Finally I address the comparison between...

Gardi, Einan

442

Electron shell and the alpha-decay  

E-Print Network [OSTI]

The ratio of the alpha-decay widths of a bare nucleus and the related atom is calculated. Both the change of the form and thus the penetrability of the potential barrier and the effect of reflection in the classically-allowed region appearing due to the electron shell are taken into account in the calculations of this ratio. The contribution of each of these two effects is of one and the same order of magnitude. For long-lived radioactive samples the values of the total effect turn out to be somewhat below 1 percent.

Sergey Yu. Igashov; Yury M. Tchuvil'sky

2012-12-03T23:59:59.000Z

443

Tunneling decay rate in quantum cosmology  

E-Print Network [OSTI]

In canonical quantum cosmology, the wave function of the universe lacks explicit time dependence. However, time evolution may be present implicitly through the semiclassical superspace variables, which themselves depend on time in classical dynamics. In this paper, we apply this approach to an oscillating universe model recently introduced by Graham et al. By extending the model to include a massless, minimally coupled scalar field $\\phi$ which has little effect on the dynamics but can play the role of a "clock", we determine the decay rate of the oscillating universe.

Mithani, Audrey T

2015-01-01T23:59:59.000Z

444

Tunneling decay rate in quantum cosmology  

E-Print Network [OSTI]

In canonical quantum cosmology, the wave function of the universe lacks explicit time dependence. However, time evolution may be present implicitly through the semiclassical superspace variables, which themselves depend on time in classical dynamics. In this paper, we apply this approach to an oscillating universe model recently introduced by Graham et al. By extending the model to include a massless, minimally coupled scalar field $\\phi$ which has little effect on the dynamics but can play the role of a "clock", we determine the decay rate of the oscillating universe.

Audrey T. Mithani; Alexander Vilenkin

2015-03-02T23:59:59.000Z

445

On charm and beauty decays: A theorist's perspective  

SciTech Connect (OSTI)

The present understanding of charm and bottom decays is reviewed. Special emphasis is placed on discussing the theoretical uncertainties in view of the particularly rich harvest of new data from the last year. A semi-quantitative description of D decays has emerged enabling us to address rather detailed and relatively subtle questions there, like on once and twice Cabibbo suppressed decays. Beauty physics having left its infancy is now in its adolescence; its future development towards maturity is analyzed.

Bigi, I.I.

1987-10-01T23:59:59.000Z

446

Neutrinoless Double Beta Decay in Supersymmetric Seesaw model  

E-Print Network [OSTI]

Inspired by the recent HEIDELBERG-MOSCOW double beta decay experiment, we discuss the neutrinoless double beta decay in the supersymmetric seesaw model. Our numerical analysis indicates that we can naturally explain the data of the observed neutrinoless double beta decay, as well as that of the solar and atmospheric neutrino experiments with at least one Majorana-like sneutrino of middle energy scale in the model.

Tai-Fu Feng; Xue-Qian Li; Yan-An Luo

2002-09-26T23:59:59.000Z

447

Results of the NEMO-3 Double Beta Decay Experiment  

E-Print Network [OSTI]

The NEMO-3 experiment is searching for neutrinoless double beta decay for 2 main isotopes (100Mo and 82Se) and is studying the two-neutrino double beta decay of seven isotopes. The experiment has been taking data since 2003 and, up to the end of 2009, showed no evidence for neutrinoless double beta decay. Two 90 % CL lower limits on the half-lives of the transitions were obtained : T_{1/2}^{0\

Mathieu BONGRAND for the NEMO-3 Collaboration

2011-05-12T23:59:59.000Z

448

Decay of Solutions to Viscous asymptotical models for waterwaves ...  

E-Print Network [OSTI]

Global Science Preprint .... We plan to let ? ?0. We then apply the ... From the energy equality in the section above, it transpires that the solution decays to 0.

2010-02-08T23:59:59.000Z

449

Searches for Leptonic B Decays at BaBar  

SciTech Connect (OSTI)

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

Nelson, Silke; /SLAC

2012-04-25T23:59:59.000Z

450

Search for New Physics in Rare Top Decays  

E-Print Network [OSTI]

Top physics provides a fertile ground for new-physics searches. At present, most top observables appear to be in good agreement with the respective Standard Model predictions. However, in the case of decay modes that are suppressed in the Standard Model, new-physics contributions of comparable magnitude may exist and yet go unnoticed because their impact on the total decay width is small. Hence it is interesting to probe rare top decays. This analysis focuses on the decay $t \\to b \\bar b c$. Useful observables are identified and prospects for measuring new-physics parameters are examined.

Pratishruti Saha

2014-11-27T23:59:59.000Z

451

Spectroscopy and Decay of $B$ Hadrons at the Tevatron  

SciTech Connect (OSTI)

The authors review recent results on heavy quark physics focusing on Run II measurements of B hadron spectroscopy and decay at the Tevatron. A wealth of new B physics measurements from CDF and D0 has been available. These include the spectroscopy of excited B states (B**, B**{sub s}) and the observation of the {Sigma}{sub b} baryon. The discussion of the decays of B hadrons and measurements of branching fractions focuses on charmless two-body decays of B {yields} h{sup +}h{sup -}. They report several new B{sub s}{sup 0} and {Lambda}{sub b}{sup 0} decay channels.

Paulini, Manfred

2007-02-01T23:59:59.000Z

452

Remarks on the formation and decay of multidimensional shock waves  

E-Print Network [OSTI]

In this paper, we present a formula describing the formation and decay of shock wave type solutions in some special cases.

V. G. Danilov

2005-12-27T23:59:59.000Z

453

About radiative kaon decay \\k+ \\to ?+\\pi0?  

E-Print Network [OSTI]

With usage of the Low theorem the general expression for amplitude of radiative kaon decay \\k+ \\to \\pi+\\pi0\\gamma is determined.

V. P. Efrosinin

2006-06-20T23:59:59.000Z

454

What can we learn from neutrinoless double beta decay experiments?  

E-Print Network [OSTI]

We assess how well next generation neutrinoless double beta decay and normal neutrino beta decay experiments can answer four fundamental questions. 1) If neutrinoless double beta decay searches do not detect a signal, and if the spectrum is known to be inverted hierarchy, can we conclude that neutrinos are Dirac particles? 2) If neutrinoless double beta decay searches are negative and a next generation ordinary beta decay experiment detects the neutrino mass scale, can we conclude that neutrinos are Dirac particles? 3) If neutrinoless double beta decay is observed with a large neutrino mass element, what is the total mass in neutrinos? 4) If neutrinoless double beta decay is observed but next generation beta decay searches for a neutrino mass only set a mass upper limit, can we establish whether the mass hierarchy is normal or inverted? We base our answers on the expected performance of next generation neutrinoless double beta decay experiments and on simulations of the accuracy of calculations of nuclear matrix elements.

John N. Bahcall; Hitoshi Murayama; Carlos Pena-Garay

2004-04-08T23:59:59.000Z

455

Mass Measurement Using Energy Spectra in Three-body Decays  

E-Print Network [OSTI]

In previous works we have demonstrated how the energy distribution of massless decay products in two body decays can be used to measure the mass of decaying particles. In this work we show how such results can be generalized to the case of multi-body decays. The key ideas that allow us to deal with multi-body final states are an extension of our previous results to the case of massive decay products and the factorization of the multi-body phase space. The mass measurement strategy that we propose is distinct from alternative methods because it does not require an accurate reconstruction of the entire event, as it does not involve, for instance, the missing transverse momentum, but rather requires measuring only the visible decay products of the decay of interest. To demonstrate the general strategy, we study a supersymmetric model wherein pair-produced gluinos each decay to a stable neutralino and a bottom quark-antiquark pair via an off-shell bottom squark. The combinatorial background stemming from the indistinguishable visible final states on both decay sides can be treated by an "event mixing" technique, the performance of which is discussed in detail. Taking into account dominant backgrounds, we are able to show that the mass of the gluino and, in favorable cases, that of the neutralino can be determined by this mass measurement strategy.

Kaustubh Agashe; Roberto Franceschini; Doojin Kim; Kyle Wardlow

2015-03-12T23:59:59.000Z

456

Role of deformation in exotic decay studies  

SciTech Connect (OSTI)

We have recently constructed a model for exotic decay studies using a cubic potential for the overlapping region that is smoothly connected by a Yukawa-plus-exponential potential for the region after separation. In this model, the zero-point vibration energy is explicitly used without violating the energy conservation and the inertial mass coefficient is made dependent on the center of mass distance, but the deformation effect has not been included. In this work, it is taken into account in both the parent and the daughter nuclei, keeping the emitted nucleus always spherical. This model is applied to the cases of {sup 14}C and {sup 24}Ne emissions and also for the recently reported cases of {sup 26}Ne, {sup 28,30}Mg, and {sup 34}Si emissions. It is found that the effect of the fragment deformation (which is always very small in the above decays) on lifetime is negligible while the parent deformation plays an appreciable role in the lifetime calculations.

Shanmugam, G.; Kamalaharan, B. (Department of Physics, Presidency College, Madras 600 005, India (IN))

1990-03-01T23:59:59.000Z

457

Interacting Dark Energy: Decay into Fermions  

E-Print Network [OSTI]

A dark energy component is responsible for the present stage of acceleration of our universe. If no fine tuning is assumed on the dark energy potential then it will end up dominating the universe at late times and the universe will not stop this stage of acceleration. On the other hand, the equation of state of dark energy seems to be smaller than -1 as suggested by the cosmological data. We take this as an indication that dark energy does indeed interact with another fluid (we consider fermion fields) and we determine the interaction through the cosmological data and extrapolate it into the future. We study the conditions under which a dark energy can dilute faster or decay into the fermion fields. We show that it is possible to live now in an accelerating epoch dominated by the dark energy and without introducing any fine tuning parameters the dark energy can either dilute faster or decaying into fermions in the future. The acceleration of the universe will then cease.

A. de la Macorra

2007-02-08T23:59:59.000Z

458

D{sup 0}-{anti D}{sup 0} mixing and doubly Cabibbo-suppressed decays of the D{sup +}  

SciTech Connect (OSTI)

This report summarizes results from Fermilab experiment E791 on D{sup 0}-{anti D}{sup 0} mixing and doubly Cabibbo-suppressed decays of the D{sup +} meson. In order to search for D{sup 0}-{anti D}{sup 0} mixing, the authors use only D{sup 0} mesons from D{sup *+} decays in which case the charge of the pion from the D{sup *+} decay identifies the charm quantum number of the D{sup 0} at birth. When the D{sup 0} decays, the charge of the kaon identifies the charm quantum number and this way one can tell if mixing has occurred. This kind of search can be carried out by CLEO II as well and their conclusion was that there is some evidence of a wrong sign signal (0.77 {+-} 0.25 {+-} 0.25)% of the right sign signal. However, because of a lack of lifetime information, they cannot distinguish between doubly Cabibbo-suppressed decays which are expected at the level of the observed signal and mixing. They use their excellent lifetime sensitivity to obtain separate limits. During the past year, the authors have been working on extracting D{sup +} doubly Cabibbo-suppressed decay signals from E791`s data sample. These decays are interesting both because they have never been observed and because definite predictions have been made about their rates, based on models of D mesons and their decay mechanisms. Preliminary analyses of 1/3 of the data have now been completed. Figure 3 shows the Cabibbo-favored signal D{sup +} {yields} K{sup {minus}}{pi}{sup +}{pi}{sup +} and the next figure shows the signal in the doubly Cabibbo-suppressed mode D{sup +} {yields} K{sup +}{pi}{sup {minus}}{pi}{sup {minus}}.

Fermilab E791 Collaboration

1994-07-01T23:59:59.000Z

459

Attenuation of excitation decay rate due to collective effect  

E-Print Network [OSTI]

We study a series of $N$ oscillators each coupled to its nearest neighbours, and linearly to a phonon field through the oscillator's number operator. We show that the Hamiltonian of a pair of adjacent oscillators, or a dimer, within the series of oscillators can be transformed to a form in which they are collectively coupled to the phonon field as a composite unit. In the weak coupling and rotating-wave approximation, the system behaves effectively like the trilinear boson model in the one excitation subspace of the dimer subsystem. The reduced dynamics of the one excitation subspace of the dimer subsystem coupled weakly to a phonon bath is similar to that of a two-level system, with a metastable state against the vacuum. The decay constant of the subsystem is proportional to the dephasing rate of the individual oscillator in a phonon bath, attenuated by a factor that depends on site asymmetry, intersite coupling and the resonance frequency between the transformed oscillator modes, or excitons. As a result of the collective effect, the excitation relaxation lifetime is prolonged over the dephasing lifetime of an individual oscillator coupled to the same bath.

B. A. Tay

2014-08-26T23:59:59.000Z

460

Localizability of Tachyonic Particles and Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

The quantum field theory of superluminal (tachyonic) particles is plagued with a number of problems, which include the Lorentz non-invariance of the vacuum state, the ambiguous separation of the field operator into creation and annihilation operators under Lorentz transformations, and the necessity of a complex reinterpretation principle for quantum processes. Another unsolved question concerns the treatment of subluminal components of a tachyonic wave packets in the field-theoretical formalism, and the calculation of the time-ordered propagator. After a brief discussion on related problems, we conclude that rather painful choices have to be made in order to incorporate tachyonic spin-1/2 particles into field theory. We argue that the field theory needs to be formulated such as to allow for localizable tachyonic particles, even if that means that a slight unitarity violation is introduced into the S matrix, and we write down field operators with unrestricted momenta. We find that once these choices have been made, the propagator for the neutrino field can be given in a compact form, and the left-handedness of the neutrino as well as the right-handedness of the antineutrino follow naturally. Consequences for neutrinoless double beta decay and superluminal propagation of neutrinos are briefly discussed.

U. D. Jentschura; B. J. Wundt

2012-01-01T23:59:59.000Z

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


461

On rings of structural numbers  

E-Print Network [OSTI]

structural numbers over the set X, and let B(X) have the operations defined above with equality also as before. Theorem I. l. If X is any set, then B(X) is a commutative ring with identity. Proof. The structural number 0 is the additive identity element... with identity g. Definition I. 7. If A, B e S(X) then A'B = (P U q ( p e A, q e B, p Il q = &f and p U q can be formed in an odd number of ways). ~E1 t. 4. L t A = (( . b), (bj. 7 )) 4 B = ((b, c), (b), (a)) be in S(X) for some X. Then AD B = {{b, a), {a...

Powell, Wayne Bruce

2012-06-07T23:59:59.000Z

462

Sense and sensitivity of double beta decay experiments  

SciTech Connect (OSTI)

The search for neutrinoless double beta decay is a very active field in which the number of proposals for next-generation experiments has proliferated. In this paper we attempt to address both the sense and the sensitivity of such proposals. Sensitivity comes first, by means of proposing a simple and unambiguous statistical recipe to derive the sensitivity to a putative Majorana neutrino mass, m{sub ??}. In order to make sense of how the different experimental approaches compare, we apply this recipe to a selection of proposals, comparing the resulting sensitivities. We also propose a ''physics-motivated range'' (PMR) of the nuclear matrix elements as a unifying criterium between the different nuclear models. The expected performance of the proposals is parametrized in terms of only four numbers: energy resolution, background rate (per unit time, isotope mass and energy), detection efficiency, and ?? isotope mass. For each proposal, both a reference and an optimistic scenario for the experimental performance are studied. In the reference scenario we find that all the proposals will be able to partially explore the degenerate spectrum, without fully covering it, although four of them (KamLAND-Zen, CUORE, NEXT and EXO) will approach the 50 meV boundary. In the optimistic scenario, we find that CUORE and the xenon-based proposals (KamLAND-Zen, EXO and NEXT) will explore a significant fraction of the inverse hierarchy, with NEXT covering it almost fully. For the long term future, we argue that {sup 136}Xe-based experiments may provide the best case for a 1-ton scale experiment, given the potentially very low backgrounds achievable and the expected scalability to large isotope masses.

Gómez-Cadenas, J.J.; Martín-Albo, J.; Sorel, M.; Ferrario, P.; Monrabal, F.; Muńoz, J. [Instituto de Física Corpuscular (IFIC), CSIC and Universidad de Valencia, Calle Catedrático José Beltrán 2, 46071 Valencia (Spain); Novella, P. [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Avda. Complutense 22, 28040 Madrid (Spain); Poves, A., E-mail: gomez@mail.cern.ch, E-mail: justo.martin-albo@ific.uv.es, E-mail: sorel@ific.uv.es, E-mail: paola.ferrario@ific.uv.es, E-mail: francesc.monrabal@ific.uv.es, E-mail: jmunoz@ific.uv.es, E-mail: pau.novella@ciemat.es, E-mail: alfredo.poves@uam.es [Dpto. de de Física Teórica and IFT-UAM/CSIC, Universidad Autónoma de Madrid, Calle Nicolás Cabrera 13-15, 28049 Madrid (Spain)

2011-06-01T23:59:59.000Z

463

An upper limit on the decay D/sup 0/. -->. mu. e  

SciTech Connect (OSTI)

A search for the lepton family number violating decay D/sup 0/ ..-->.. ..mu..e is reported. No signal is observed in a data sample of 9.3 pb/sup -1/ collected at the psi(3770) resonance with the Mark III detector, where 0.18 +- 0.06 +- 0.05 background events are expected. A 90% confidence level upper limit on the branching fraction B(D/sup 0/ ..-->.. ..mu..e) of 1.5 x 10/sup -4/ is obtained.

Stockhausen, W.

1987-04-01T23:59:59.000Z

464

Nuclear matrix elements for neutrinoless double-beta decay and double-electron capture  

E-Print Network [OSTI]

A new generation of neutrinoless double beta decay experiments with improved sensitivity is currently under design and construction. They will probe inverted hierarchy region of the neutrino mass pattern. There is also a revived interest to the resonant neutrinoless double-electron capture, which has also a potential to probe lepton number conservation and to investigate the neutrino nature and mass scale. The primary concern are the nuclear matrix elements. Clearly, the accuracy of the determination of the effective Majorana neutrino mass from the measured 0\

Amand Faessler; Vadim Rodin; Fedor Simkovic

2012-06-03T23:59:59.000Z

465

Relativistic QRPA Calculation of {beta}-Decay Rates of r-process Nuclei  

SciTech Connect (OSTI)

A systematic, fully self-consistent calculation of {beta}-decay rates is presented, based on a microscopic theoretical framework. Analysis is performed on a large number of nuclei from the valley of {beta} stability towards the neutron drip-line. Nuclear ground state is determined using the Relativistic Hartree-Bogoliubov (RHB) model with density-dependent meson-nucleon coupling constants. Transition rates are calculated within the proton-neutron relativistic quasiparticle RPA (pn-RQRPA) using the same interaction that was used in the RHB equations.

Marketin, T.; Paar, N.; Niksic, T.; Vretenar, D. [Physics Department, University of Zagreb (Croatia); Ring, P. [Physik Department der Technischen Universitaet Muenchen (Germany)

2009-08-26T23:59:59.000Z

466

Charged-Particle Decay from Giant Monopole Resonance in Si-28  

E-Print Network [OSTI]

PHYSICAL REVIEW C VOLUME 41, NUMBER 4 APRIL 1990 Charged particle decay from giant monopole resonance in Si Y. Toba, Y.-W. Lui, and D. H. Youngblood Cyclotron Institute, Texas A&M University, College Station, Texas 77843 U. Garg Physics... elusive with only a few percent of the sum rule located in most nuclei. Lui et al. reported the identification of 66/o of the EO EWSR with a width of 4.8 MeV centered at 17.9 MeV in Si. Si was also investigated by Kailas et al. , using 115 MeV proton...

Toba, Y.; Lui, YW; Youngblood, David H.; Garg, U.; Grabmayr, P.; Knopfle, K. T.; Riedesel, H.; Wagner, G. J.

1990-01-01T23:59:59.000Z

467

The $Z_H \\to \\gamma H$ decay in the Littlest Higgs Model  

E-Print Network [OSTI]

We present the calculation of the $Z_H \\to \\gamma H$ decay in the context of the Littlest Higgs model at one-loop level. Our calculations include the contributions of fermions, scalars and gauge bosons in accordance with the most recent experimental constraints on the parameters space of the model. We find branching ratios of the order of $10^{-5}$ for the energy scale $f=2,3,4$ TeV on the $0.1energy of 14 TeV. By using the integrated luminosity projected for the Large Hadron Collider in the last stage of operation, we estimated the number of events for this process.

Aranda, J I; Ramírez-Zavaleta, F; Tututi, E S

2015-01-01T23:59:59.000Z

468

Significant neutrinoless double beta decay with quasi-Dirac neutrinos  

E-Print Network [OSTI]

A significant signal of neutrinoless double beta decay can be consistent with the existence of light quasi-Dirac neutrinos. To demonstrate this possibility, we consider a realistic model where the neutrino masses and the neutrinoless double beta decay can be simultaneously generated after a Peccei-Quinn symmetry breaking.

Pei-Hong Gu

2012-09-13T23:59:59.000Z

469

Mass Measurement Using Energy Spectra in Three-body Decays  

E-Print Network [OSTI]

In previous works we have demonstrated how the energy distribution of massless decay products in two body decays can be used to measure the mass of decaying particles. In this work we show how such results can be generalized to the case of multi-body decays. The key ideas that allow us to deal with multi-body final states are an extension of our previous results to the case of massive decay products and the factorization of the multi-body phase space. The mass measurement strategy that we propose is distinct from alternative methods because it does not require an accurate reconstruction of the entire event, as it does not involve, for instance, the missing transverse momentum, but rather requires measuring only the visible decay products of the decay of interest. To demonstrate the general strategy, we study a supersymmetric model wherein pair-produced gluinos each decay to a stable neutralino and a bottom quark-antiquark pair via an off-shell bottom squark. The combinatorial background stemming from the indi...

Agashe, Kaustubh; Kim, Doojin; Wardlow, Kyle

2015-01-01T23:59:59.000Z

470

Double beta decay to the excited states: experimental review  

E-Print Network [OSTI]

A brief review on double beta decay to excited states of daughter nuclei is given. The ECEC(ov) transision to the excited states are discussed in association with a possible enhancement of the decay rate by several orders of magnitude.

A. S. Barabash

2007-10-11T23:59:59.000Z

471

SciTech Connect: Beta Decay of B12  

Office of Scientific and Technical Information (OSTI)

Journal Article: Beta Decay of B12 Citation Details In-Document Search Title: Beta Decay of B12 The 3.23-Mev gamma-ray transition between the 7.66 and 4.43-Mev states of C12 has...

472

Dalitz Analysis of Three-Body B Decays  

E-Print Network [OSTI]

Results on Dalitz analysis of three-body charmless B+=>K+pi+pi- and B+=>K+K+K- decays are reported. We also present preliminary results on the studies of direct CP violation in three-body decay B+-=>K+-pi+pi-. The analysis is performed using a large data sample collected with the Belle detector.

A. Garmash; for the Belle Collaboration

2005-05-16T23:59:59.000Z

473

Evidence for the Decay X(3872) ? ?(2S)?  

E-Print Network [OSTI]

Evidence for the decay mode X(3872) ? ?(2S)? in B[superscript +] ? X(3872)K[superscript +] decays is found with a significance of 4.4 standard deviations. The analysis is based on a data sample of proton–proton collisions, ...

Counts, Ian Thomas Hunt

474

Neutrinoless double-{beta} decay: Status and future  

SciTech Connect (OSTI)

A brief summary of the status of neutrino masses, mixing, and oscillations is presented. Neutrinoless double {beta} decay is considered. Predictions for the effective Majorana mass are reviewed. A possible test of the calculations of nuclear matrix elements of the 0{nu}{beta}{beta} decay is proposed.

Bilenky, S. M. [Joint Institute for Nuclear Research (Russian Federation)], E-mail: bilenky@he.sissa.it

2006-12-15T23:59:59.000Z

475

Strategies for Next Generation Neutrinoless Double-Beta Decay Experiments  

E-Print Network [OSTI]

Strategies for Next Generation Neutrinoless Double-Beta Decay Experiments F. T. Avignone III A brief discussion of the connection between neutrino oscillation data and predictions of neutrinoless the necessary tools for comparative evaluation. 1. INTRODUCTION Neutrinoless double-beta (0)-decay has been

476

Neutrinoless double-beta decay. A brief review  

E-Print Network [OSTI]

In this brief review we discuss the generation of Majorana neutrino masses through the see-saw mechanism, the theory of neutrinoless double-beta decay, the implications of neutrino oscillation data for the effective Majorana mass, taking into account the recent Daya Bay measurement of theta_13, and the interpretation of the results of neutrinoless double-beta decay experiments.

S. M. Bilenky; C. Giunti

2012-03-23T23:59:59.000Z

477

Study of Bc->KK decay with perturbative QCD approach  

E-Print Network [OSTI]

In the framework of the perturbative QCD approach, we study the charmless pure weak annihilation Bc->KK decay and find that the branching ratio BR(Bc->KK) O(10^-7). This prediction is so tiny that the Bc->KK decay might be unmeasurable at the Large Hadron Collider.

Yue-Ling Yang; Jun-Feng Sun; Na Wang

2010-04-16T23:59:59.000Z

478

Hadronic B decays at BaBar and Belle  

SciTech Connect (OSTI)

The authors review recent results of the BABAR and Belle Collaborations on the {alpha} and {gamma} angles of the unitarity triangle, on the B {yields} K{pi}{pi} Dalitz-plot analyses, and on the searches for baryonic B decays and for B {yields} D{bar D} decays.

Lombardo, Vincenzo; /Milan U. /INFN, Milan

2008-08-11T23:59:59.000Z

479

Double Beta Decay and the Absolute Neutrino Mass Scale  

E-Print Network [OSTI]

After a short review of the current status of three-neutrino mixing, the implications for the values of neutrino masses are discussed. The bounds on the absolute scale of neutrino masses from Tritium beta-decay and cosmological data are reviewed. Finally, we discuss the implications of three-neutrino mixing for neutrinoless double-beta decay.

Carlo Giunti

2003-08-20T23:59:59.000Z

480

First search for CP violation in tau lepton decay  

E-Print Network [OSTI]

We have performed the first search for CP violation in tau lepton decay. CP violation in lepton decay does not occur in the minimal standard model but can occur in extensions such as the multi-Higgs doublet model. It appears as a characteristic...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

1998-11-01T23:59:59.000Z

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


481

anisotropic decay dynamics: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

anisotropic decay dynamics First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Anisotropic decay dynamics...

482

Half-lives of Double $\\beta ^+$-decay with Two Neutrinos  

E-Print Network [OSTI]

Nuclear double $\\beta ^-$-decays with two neutrinos were observed for many years and a systematic law describing the relation between their half-lives and decay energies was also proposed recently [Phys. Rev. C89, 064603 (2014)]. However, double $\\beta ^+$-decay ($\\beta ^+\\beta^+)$ with emission of both two positrons and two neutrinos has not been observed up to date. In this article, we perform a systematic analysis on the candidates of double $\\beta ^+$-decay, based on the 2012 nuclear mass table. Eight nuclei are found to be the good candidates for double $\\beta ^+$-decay and their half-lives are predicted according to the generalization of the systematic law to double $\\beta ^+$-decay. As far as we know, there is no theoretical result on double $\\beta ^+$-decay of nucleus $^{154}Dy$ and our result is the first prediction on this nucleus. This is also the first complete research on eight double $\\beta ^+$-decay candidates based on the available data of nuclear masses. It is expected that the calculated hal...

Ren, Yuejiao

2015-01-01T23:59:59.000Z

483

The Effect of Quark Sector Minimal Flavor Violation on Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

The question of whether neutrino masses are Dirac or Majorana is one of the most important, and most difficult, questions remaining in the neutrino sector. Searches for neutrinoless double beta-decay may help to resolve this question, but are also sensitive to new, higher dimension Delta L=2 operators. In this paper we place two phenomenological constraints on these operators at dimension d<=11. First, we require that the operators obey the quark flavor symmetries of the Standard Model, with any violation of the symmetries being due to Yukawa interactions, a scheme known as Minimal Flavor Violation (MFV). Second, we require that the operators which generate neutrinoless double beta-decay, and any operators related by the flavor symmetries, do not induce neutrino masses above 0.05 eV, the limit implied by the atmospheric neutrino data. We find that these requirements severely constrain the operators which can violate lepton number, such that most can no longer contribute to neutrinoless double beta-decay at observable rates. It is noteworthy that quark flavor symmetries can play such a strong role in constraining new leptonic physics, even when that physics is not quark flavor changing. Those few operators that can mimic a Majorana neutrino mass then appear with cutoffs below a TeV, and represent new physics which could be directly probed at the LHC or a future linear collider.

Brian Dudley; Christopher Kolda

2008-10-16T23:59:59.000Z

484

B - L violating nucleon decay and GUT scale baryogenesis in SO(10)  

SciTech Connect (OSTI)

Minimal SO(10) models which utilize a 126-plet of Higgs for breaking B - L symmetry are predictive schemes for neutrino masses and mixings. These models have been known to predict sin{sup 2}2{theta}{sub 13} Asymptotically-Equal-To 0.09, which is consistent with recent measurements. It is shown that the same class of models generates naturally baryon number violating dimension seven operators leading to novel nucleon decay modes such as n{yields}e{sup -}K{sup +}, e{sup -}{pi}{sup +} and p{yields}{nu}{pi}{sup +} which violate B - L by two units. We find that in two-step breaking schemes of non-supersymmetric SO(10), the partial lifetimes for these modes can be within reach of experiments. The interactions responsible for these decay modes also provide a new way to understand the origin of matter in the universe via the decays of GUT scale colored scalar bosons. Their (B - L)-violating nature guarantees that the GUT scale induced baryon asymmetry is not washed out by the electroweak sphaleron interactions. In minimal SO(10) models this asymmetry is closely tied to the masses of quarks, leptons and the neutrinos.

Babu, K. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2012-07-27T23:59:59.000Z

485

Effect of quark sector minimal flavor violation on neutrinoless double beta decay  

SciTech Connect (OSTI)

The question of whether neutrino masses are Dirac or Majorana is one of the most important, and most difficult, questions remaining in the neutrino sector. Searches for neutrinoless double {beta} decay may help to resolve this question, but are also sensitive to new, higher-dimension {delta}L=2 operators. In this paper we place two phenomenological constraints on these operators at dimension d{<=}11. First, we require that the operators obey the quark flavor symmetries of the standard model, with any violation of the symmetries being due to Yukawa interactions, a scheme known as minimal flavor violation. Second, we require that the operators which generate neutrinoless double {beta} decay, and any operators related by the flavor symmetries, do not induce neutrino masses above the experimental and astrophysical limits. We find that these requirements severely constrain the operators which can violate lepton number, such that most can no longer contribute to neutrinoless double {beta} decay at observable rates. It is noteworthy that quark flavor symmetries can play such a strong role in constraining new leptonic physics, even when that physics is not quark flavor changing. Those few operators that can mimic a Majorana neutrino mass then appear with cutoffs below a TeV, and represent new physics which could be directly probed at the LHC or a future linear collider.

Dudley, Brian; Kolda, Christopher [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

2009-01-01T23:59:59.000Z

486

Evidence for the direct decay of the 125 GeV Higgs boson to fermions  

E-Print Network [OSTI]

The discovery of a new boson with a mass of approximately 125 GeV in 2012 at the LHC has heralded a new era in understanding the nature of electroweak symmetry breaking and possibly completing the standard model of particle physics. Since the first observation in decays to gamma-gamma, WW, and ZZ boson pairs, an extensive set of measurements of the mass and couplings to W and Z bosons, as well as multiple tests of the spin-parity quantum numbers, have revealed that the properties of the new boson are consistent with those of the long-sought agent responsible for electroweak symmetry breaking. An important open question is whether the new particle also couples to fermions, and in particular to down-type fermions, since the current measurements mainly constrain the couplings to the up-type top quark. Determination of the couplings to down-type fermions requires direct measurement of the corresponding Higgs boson decays, as recently reported by the CMS experiment in the study of Higgs decays to bottom quarks and...

Chatrchyan, Serguei; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hartl, Christian; Hörmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knünz, Valentin; Krammer, Manfred; Krätschmer, Ilse; Liko, Dietrich; Mikulec, Ivan; Rabady, Dinyar; Rahbaran, Babak; Rohringer, Herbert; Schöfbeck, Robert; Strauss, Josef; Taurok, Anton; Treberer-Treberspurg, Wolfgang; Waltenberger, Wolfgang; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Alderweireldt, Sara; Bansal, Monika; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Knutsson, Albert; Luyckx, Sten; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Heracleous, Natalie; Kalogeropoulos, Alexis; Keaveney, James; Kim, Tae Jeong; Lowette, Steven; Maes, Michael; Olbrechts, Annik; Python, Quentin; Strom, Derek; Tavernier, Stefaan; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Caillol, Cécile; Clerbaux, Barbara; De Lentdecker, Gilles; Favart, Laurent; Gay, Arnaud; Léonard, Alexandre; Marage, Pierre Edouard; Mohammadi, Abdollah; Pernič, Luca; Reis, Thomas; Seva, Tomislav; Thomas, Laurent; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Adler, Volker; Beernaert, Kelly; Benucci, Leonardo; Cimmino, Anna; Costantini, Silvia; Crucy, Shannon; Dildick, Sven; Garcia, Guillaume; Klein, Benjamin; Lellouch, Jérémie; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Ryckbosch, Dirk; Salva Diblen, Sinem; Sigamani, Michael; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Walsh, Sinead; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Beluffi, Camille; Bruno, Giacomo; Castello, Roberto; Caudron, Adrien; Ceard, Ludivine; Da Silveira, Gustavo Gil; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Jez, Pavel; Komm, Matthias; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Nuttens, Claude; Pagano, Davide; Pin, Arnaud; Piotrzkowski, Krzysztof; Popov, Andrey; Quertenmont, Loic; Selvaggi, Michele; Vidal Marono, Miguel; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Alves, Gilvan; Correa Martins Junior, Marcos; Dos Reis Martins, Thiago; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Aldá Júnior, Walter Luiz; Carvalho, Wagner; Chinellato, Jose; Custódio, Analu; Da Costa, Eliza Melo; De Jesus Damiao, Dilson; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Malbouisson, Helena; Malek, Magdalena; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Prado Da Silva, Wanda Lucia; Santaolalla, Javier; Santoro, Alberto; Sznajder, Andre; Tonelli Manganote, Edmilson José; Vilela Pereira, Antonio; Bernardes, Cesar Augusto; De Almeida Dias, Flavia; Tomei, Thiago; De Moraes Gregores, Eduardo; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Genchev, Vladimir; Iaydjiev, Plamen; Marinov, Andrey; Piperov, Stefan; Rodozov, Mircho; Sultanov, Georgi; Vutova, Mariana; Dimitrov, Anton; Glushkov, Ivan; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Chen, Mingshui; Du, Ran; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Meng, Xiangwei; Plestina, Roko; Tao, Junquan; Wang, Xianyou; Wang, Zheng; Asawatangtrakuldee, Chayanit; Ban, Yong; Guo, Yifei; Li, Qiang; Li, Wenbo; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Wang, Dayong; Zhang, Linlin; Zou, Wei; Avila, Carlos; Chaparro Sierra, Luisa Fernanda; Florez, Carlos; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Kadija, Kreso; Luetic, Jelena; Mekterovic, Darko; Morovic, Srecko; Sudic, Lucija; Attikis, Alexandros; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Bodlak, Martin; Finger, Miroslav; Finger Jr, Michael; Assran, Yasser; Elgammal, Sherif; Ellithi Kamel, Ali; Mahmoud, Mohammed; Mahrous, Ayman; Radi, Amr; Kadastik, Mario; Müntel, Mait; Murumaa, Marion; Raidal, Martti; Tiko, Andres; Eerola, Paula; Fedi, Giacomo; Voutilainen, Mikko; Härkönen, Jaakko; Karimäki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampén, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindén, Tomas

2014-01-01T23:59:59.000Z

487

Progress in computing inclusive B decay spectra.  

E-Print Network [OSTI]

ar X iv :h ep -p h/ 06 01 18 1v 1 2 1 Ja n 20 06 Progress in computing inclusive B decay spectra Einan Gardi and Jeppe R. Andersen Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK We review the progress... V, M0E =1.7GeV x =1GeV, M0E =1.7GeV, fully diff. x =1GeV, M0E =0.66GeV max + =1GeV, P0E =0.66GeV, fully diff. max + =1GeV, P0E Figure 4. The P? spectrum in BŻ ?? Xul?Ż as calculated by DGE [17], after integration over P+ and El in four different...

Gardi, Einan; Andersen, Jeppe R

488

Neutrinoless Double Beta Decay with SNO+  

E-Print Network [OSTI]

SNO+ will search for neutrinoless double beta decay by loading 780 tonnes of linear alkylbenzene liquid scintillator with O(tonne) of neodymium. Using natural Nd at 0.1% loading will provide 43.7 kg of 150Nd given its 5.6% abundance and allow the experiment to reach a sensitivity to the effective neutrino mass of 100-200 meV at 90% C.L in a 3 year run. The SNO+ detector has ultra low backgrounds with 7000 tonnes of water shielding and self-shielding of the scintillator. Distillation and several other purification techniques will be used with the aim of achieving Borexino levels of backgrounds. The experiment is fully funded and data taking with light-water will commence in 2012 with scintillator data following in 2013.

J. Hartnell; for the SNO+ collaboration

2012-01-30T23:59:59.000Z

489

Nonsingular Decaying Vacuum Cosmology and Entropy Production  

E-Print Network [OSTI]

The thermodynamic behavior of a decaying vacuum cosmology describing the entire cosmological history evolving between two extreme (early and late time) de Sitter eras is investigated. The thermal evolution from the early de Sitter to the radiation phase is discussed in detail. The temperature evolution law and the increasing entropy function are analytically determined. The entropy of the effectively massless particles is initially zero but evolves continuously to the present day maximum value within the current Hubble radius, $S_0 \\sim 10^{88}$ in natural units. By using the Gibbons-Hawking temperature relation for the de Sitter spacetime, it is found that the ratio between the primeval and the late time vacuum energy densities is $\\rho_{vI}/\\rho_{v0} \\sim 10^{123}$, as required by some naive estimates from quantum field theory.

J. A. S. Lima; S. Basilakos; Joan Solŕ

2015-03-08T23:59:59.000Z

490

Neutrinoless Double Beta Decay in Gauge Theories  

E-Print Network [OSTI]

Neutrinoless double beta decay is a very important process both from the particle and nuclear physics point of view. Its observation will severely constrain the existing models and signal that the neutrinos are massive Majorana particles. From the elementary particle point of view it pops up in almost every model. In addition to the traditional mechanisms, like the neutrino mass, the admixture of right handed currents etc, it may occur due to the R-parity violating supersymmetric (SUSY) interactions. From the nuclear physics point of view it is challenging, because: 1) The relevant nuclei have complicated nuclear structure. 2) The energetically allowed transitions are exhaust a small part of all the strength. 3) One must cope with the short distance behavior of the transition operators, especially when the intermediate particles are heavy (eg in SUSY models). Thus novel effects, like the double beta decay of pions in flight between nucleons, have to be considered. 4) The intermediate momenta involved are about 100 MeV. Thus one has to take into account possible momentum dependent terms in the nucleon current. We find that, for the mass mechanism, such modifications of the nucleon current for light neutrinos reduce the nuclear matrix elements by about 25 per cent, almost regardless of the nuclear model. In the case of heavy neutrinos the effect is much larger and model dependent. Taking the above effects into account, the available nuclear matrix elements for the experimentally interesting nuclei A = 76, 82, 96, 100, 116, 128, 130, 136 and 150 and the experimental limits on the life times we have extracted new stringent limits on the average neutrino mass and on the R-parity violating coupling for various SUSY models.

J. D. Vergados

1999-07-12T23:59:59.000Z

491

Constraining Mass Spectra with Sterile Neutrinos from Neutrinoless Double Beta Decay, Tritium Beta Decay and Cosmology  

E-Print Network [OSTI]

We analyze the constraints on neutrino mass spectra with extra sterile neutrinos as implied by the LSND experiment. The various mass related observables in neutrinoless double beta decay, tritium beta decay and cosmology are discussed. Both neutrino oscillation results as well as recent cosmological neutrino mass bounds are taken into account. We find that some of the allowed mass patterns are severely restricted by the current constraints, in particular by the cosmological constraints on the total sum of neutrino masses and by the non-maximality of the solar neutrino mixing angle. Furthermore, we estimate the form of the four neutrino mass matrices and also comment on the situation in scenarios with two additional sterile neutrinos.

Srubabati Goswami; Werner Rodejohann

2006-05-18T23:59:59.000Z

492

Constraining mass spectra with sterile neutrinos from neutrinoless double beta decay, tritium beta decay, and cosmology  

SciTech Connect (OSTI)

We analyze the constraints on neutrino mass spectra with extra sterile neutrinos as implied by the LSND experiment. The various mass related observables in neutrinoless double beta decay, tritium beta decay and cosmology are discussed. Both neutrino oscillation results as well as recent cosmological neutrino mass bounds are taken into account. We find that some of the allowed mass patterns are severely restricted by the current constraints, in particular, by the cosmological constraints on the total sum of neutrino masses and by the nonmaximality of the solar neutrino mixing angle. Furthermore, we estimate the form of the four neutrino mass matrices and also comment on the situation in scenarios with two additional sterile neutrinos.

Goswami, Srubabati [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India); Physik-Department, Technische Universitaet Muenchen, James-Franck-Strasse, D-85748 Garching (Germany); Rodejohann, Werner [Physik-Department, Technische Universitaet Muenchen, James-Franck-Strasse, D-85748 Garching (Germany)

2006-06-01T23:59:59.000Z

493

Complex-Energy Shell-Model Description of Alpha Decay  

SciTech Connect (OSTI)

In his pioneering work of alpha decay, Gamow assumed that the alpha particle formed inside the nucleus tunnels through the barrier of the alpha-daughter potential. The corresponding metastable state can be viewed as a complex-energy solution of the time-independent Schroedinger equation with the outgoing boundary condition. The formation of the alpha cluster, missing in the original Gamow formulation, can be described within the R-matrix theory in terms of the formation amplitude. In this work, the alpha decay process is described by computing the formation amplitude and barrier penetrability in a large complex-energy configuration space spanned by the complex-energy eigenstates of the finite Woods-Saxon (WS) potential. The proper normalization of the decay channel is essential as it strongly modifies the alpha-decay spectroscopic factor. The test calculations are carried out for the ^{212}Po alpha decay.

Id Betan, R. [Rosario Physics Institute, Rosario, Argentina] [Rosario Physics Institute, Rosario, Argentina; Nazarewicz, Witold [ORNL] [ORNL

2011-01-01T23:59:59.000Z

494

Dark radiation from particle decay: cosmological constraints and opportunities  

SciTech Connect (OSTI)

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.

Hasenkamp, Jasper; Kersten, Jörn, E-mail: Jasper.Hasenkamp@desy.de, E-mail: Joern.Kersten@desy.de [II. Institute for Theoretical Physics, University of Hamburg, 22761 Hamburg (Germany)

2013-08-01T23:59:59.000Z

495

Dark radiation from particle decay: cosmological constraints and opportunities  

E-Print Network [OSTI]

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.

Jasper Hasenkamp; Jörn Kersten

2014-02-13T23:59:59.000Z

496

Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors  

E-Print Network [OSTI]

Exploring the Neutrinoless Double Beta Decay in the InvertedC. Giunti, Neutrinoless double-beta decay. A brief review,el- ements for neutrinoless double-beta decay and double-

Artusa, D. R.

2014-01-01T23:59:59.000Z

497

First results on neutrinoless double beta decay of Te-130 with the calorimetric cuoricino experiment  

E-Print Network [OSTI]

Evidence for Neutrinoless Double Beta Decay” arXiv:hep-on “Evidence for neutrinoless double beta decay”- arXiv:hep-Results on Neutrinoless Double Beta Decay of 130 Te with the

2003-01-01T23:59:59.000Z

498

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

E-Print Network [OSTI]

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

Cowan, Ray Franklin

499

Decay of an Ultracold Fermionic Lithium Gas near a Feshbach Resonance K. Dieckmann, C. A. Stan, S. Gupta, Z. Hadzibabic, C. H. Schunck, and W. Ketterle  

E-Print Network [OSTI]

Decay of an Ultracold Fermionic Lithium Gas near a Feshbach Resonance K. Dieckmann, C. A. Stan, S.203201 PACS numbers: 05.30.Fk, 32.80.Pj, 34.50.-s, 39.25.+k Interactions between atoms can be strongly as the colliding atoms. This mechanism has been used to dramatically alter the properties of ultracold bosonic

500

Origin of the Structures in the C-12(o-16,alpha) Reaction - Dominance of Ne-20-Star and O-16-Star Sequential Alpha-Decay Processes  

E-Print Network [OSTI]

PHYSICAL REVIEW C. VOLUME 29, NUMBER 3 MARCH 1984 Origin of the structures in the ' C(' O,a) reaction: Dominance of oNe' and ' 0' sequential a-decay processes T. Murakami, * E. Ungricht, N. Takahashi, ~ Y.-%'. Lui, Y. Mihara, ~ R. E. Neese, E...

Murakami, T.; Ungricht, E.; Takahashi, N.; Lui, YW; Mihara, Y.; Neese, R. E.; Takada, E.; Tanner, D. M.; Tribble, Robert E.; Nagatani, K.

1984-01-01T23:59:59.000Z