Ringbom, A; Conde, H; Elmgren, K; Olsson, N; Rahm, J; Rönnqvist, T; Jonsson, O; Nilsson, L; Renberg, P U; Tibell, G; Bargholtz, C; Fransson, K; Lindh, K; Tegnér, P E; Thörngren-Engblom, P; Van der Werf, S Y
2001-01-01
Double-differential cross sections of the sup 1 sup 0 sup , sup 1 sup 1 B(n, p) sup 1 sup 0 sup , sup 1 sup 1 Be reactions have been measured at 96 MeV in the angular range 0 deg. -30 deg. for excitation energies up to 35 MeV. The spectra have been decomposed into different multipolarities using sample angular distributions calculated within the distorted-wave Born approximation. From the identified Gamow-Teller strength, S subbeta sub sup + values were obtained for sup 1 sup 0 B and sup 1 sup 1 B. At higher excitation energies, the spectra are dominated by L=1 strength in broad distributions with maxima around 22 and 12 MeV in sup 1 sup 0 B and sup 1 sup 1 B, respectively.
Superallowed Gamow-Teller decay of the doubly magic nucleus 100Sn.
Hinke, C B; Böhmer, M; Boutachkov, P; Faestermann, T; Geissel, H; Gerl, J; Gernhäuser, R; Górska, M; Gottardo, A; Grawe, H; Grębosz, J L; Krücken, R; Kurz, N; Liu, Z; Maier, L; Nowacki, F; Pietri, S; Podolyák, Zs; Sieja, K; Steiger, K; Straub, K; Weick, H; Wollersheim, H-J; Woods, P J; Al-Dahan, N; Alkhomashi, N; Ataç, A; Blazhev, A; Braun, N F; Čeliković, I T; Davinson, T; Dillmann, I; Domingo-Pardo, C; Doornenbal, P C; de France, G; Farrelly, G F; Farinon, F; Goel, N; Habermann, T C; Hoischen, R; Janik, R; Karny, M; Kaşkaş, A; Kojouharov, I M; Kröll, Th; Litvinov, Y; Myalski, S; Nebel, F; Nishimura, S; Nociforo, C; Nyberg, J; Parikh, A R; Procházka, A; Regan, P H; Rigollet, C; Schaffner, H; Scheidenberger, C; Schwertel, S; Söderström, P-A; Steer, S J; Stolz, A; Strmeň, P
2012-06-20
The shell structure of atomic nuclei is associated with 'magic numbers' and originates in the nearly independent motion of neutrons and protons in a mean potential generated by all nucleons. During β(+)-decay, a proton transforms into a neutron in a previously not fully occupied orbital, emitting a positron-neutrino pair with either parallel or antiparallel spins, in a Gamow-Teller or Fermi transition, respectively. The transition probability, or strength, of a Gamow-Teller transition depends sensitively on the underlying shell structure and is usually distributed among many states in the neighbouring nucleus. Here we report measurements of the half-life and decay energy for the decay of (100)Sn, the heaviest doubly magic nucleus with equal numbers of protons and neutrons. In the β-decay of (100)Sn, a large fraction of the strength is observable because of the large decay energy. We determine the largest Gamow-Teller strength so far measured in allowed nuclear β-decay, establishing the 'superallowed' nature of this Gamow-Teller transition. The large strength and the low-energy states in the daughter nucleus, (100)In, are well reproduced by modern, large-scale shell model calculations.
Gamow-Teller strength in the continuum and quenching problem
Sakai, H; Okamura, H; Nonaka, T; Ohnishi, T; Yako, K; Sekiguchi, K; Fujita, S; Satou, Y; Otsu, H; Uesaka, T; Ishida, S; Sakamoto, N; Greenfield, M B; Hatanaka, K
1999-01-01
Differential cross sections at theta sub l sub a sub b = 0.0 deg. - 12.3 deg. and a complete set of polarization transfer observables at theta sub l sub a sub b = 0.0 deg. are measured for the sup 9 sup 0 Zr(p, n) reaction at T sub p = 295 MeV. A multipole decomposition (MD) technique is applied to the cross sections to extract partial cross sections sigma sub L with L = 0, 1, 2, and 3 contributions. A significant amount of sigma sub L sub = sub 0 is found in the highly excited continuum region. After subtracting the estimated iso-vector spin-monopole strength from sigma sub L sub = sub 0 , the Gamow-Teller (GT) strength B(GT) is deduced to be S subbeta sub - = SIGMA B(GT) = 28 +- 1.6 +- 5.4. The total spin transfer SIGMA(0 deg. ) which is independent of the nuclear reaction mechanisms such as the effective nucleon-nucleon interaction or distortions is derived from the complete set of polarization transfer observables. It is close to unity up to 50 MeV excitation indicating the strong spin-flip character of t...
Gamow-Teller response and its spreading mechanism in doubly magic nuclei
Niu, Y. F.; Colò, G.; Vigezzi, E.
2014-11-01
The scope of the paper is to apply a state-of-the-art beyond mean-field model to the description of the Gamow-Teller response in atomic nuclei. This topic recently attracted considerable renewed interest, due, in particular, to the possibility of performing experiments in unstable nuclei. We study the cases of 48Ca,78Ni,132Sn, and 208Pb. Our model is based on a fully self-consistent Skyrme Hartree-Fock plus random phase approximation. The same Skyrme interaction is used to calculate the coupling between particles and vibrations, which leads to the mixing of the Gamow-Teller resonance with a set of doorway states and to its fragmentation. We compare our results with available experimental data. The microscopic coupling mechanism is also discussed in some detail.
Gamow-Teller response and its spreading mechanism in doubly magic nuclei
Niu, Yifei; Vigezzi, Enrico
2015-01-01
The scope of the paper is to apply a state-of-the-art beyond mean-field model to the description of the Gamow-Teller response in atomic nuclei. This topic recently attracted considerable renewed interest, due, in particular, to the possibility of performing experiments in unstable nuclei. We study the cases of $^{48}$Ca, $^{78}$Ni, $^{132}$Sn and $^{208}$Pb. Our model is based on a fully self-consistent Skyrme Hartree-Fock plus random phase approximation. The same Skyrme interaction is used to calculate the coupling between particles and vibrations, which leads to the mixing of the Gamow-Teller resonance with a set of doorway states and to its fragmentation. We compare our results with available experimental data. The microscopic coupling mechanism is also discussed in some detail.
Shell model method for Gamow-Teller Transitions in heavy, deformed nuclei
Gao, Z C; Sun, Y; Gao, Zao-Chun; Sun, Yang
2006-01-01
A method for calculation of Gamow-Teller transition rates is developed by using the concept of the Projected Shell Model (PSM). The shell model basis is constructed by superimposing angular-momentum-projected multi-quasiparticle configurations, and nuclear wave functions are obtained by digonalizing the two-body interactions in these projected states. Calculation of transition matrix elements in the PSM framework is discussed in detail, and the effects caused by the Gamow-Teller residual forces and by configuration-mixing are studied. With this method, it may become possible to perform a state-by-state calculation for beta-decay and electron-capture rates in heavy, deformed nuclei at finite temperatures. Our first example indicates that, while experimentally known Gamow-Teller transition rates from the ground state of the parent nucleus are reproduced, stronger transitions from some low-lying excited states are predicted to occur, which may considerably enhance the total decay rates once these nuclei are expo...
Role of the momentum transfer in the quenching of the Gamow-Teller strength
Energy Technology Data Exchange (ETDEWEB)
Marketin, Tomislav [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany); Physics Department, Faculty of Science, University of Zagreb (Croatia); Martinez-Pinedo, Gabriel [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany); Paar, Nils; Vretenar, Dario [Physics Department, Faculty of Science, University of Zagreb (Croatia)
2012-07-01
A fully consistent calculation of the Gamow-Teller strength is presented, based on a microscopic theoretical framework. Nuclear ground state is determined using the relativistic Hartree-Bogolyubov (RHB) model with density dependent meson-nucleon coupling constants, and transition rates are calculated via proton-neutron relativistic quasiparticle RPA using the same interaction as in the RHB equations. The (p,n) probe has a similar spin-isospin operator structure to the Gamow-Teller (GT) operator. However, they become comparable only if the GT cross section is measured at a very small momentum transfer q. At higher momentum transfer the isovector spin monopole (IVSM) mode occurs, with the r{sup 2}{sigma}{tau} transition operator. Unlike the Gamow-Teller operator which excites only the 0{Dirac_h}{omega} transitions, the isovector spin monopole operator can also excite 2{Dirac_h}{omega} transitions and can change the strength distribution at high excitation energies. We explore the strength beyond the resonance, examine the effect of momentum transfer on the total strength and compare the results with recent measurements.
Gamow-Teller beta decay of {sup 105}Sn
Energy Technology Data Exchange (ETDEWEB)
Kavatsyuk, M.; Kavatsyuk, O. [GSI, Darmstadt (Germany); Univ. of Kyiv (Ukraine); Batist, L. [St. Petersburg Nuclear Physics Inst. (Russian Federation); Napoli Univ. (Italy); INFN, Napoli (Italy); Becker, F.; Bruechle, W.; Doering, J.; Gorska, M.; Grawe, H.; Kirchner, R.; Mandal, S.; Mazzocchi, C.; Plettner, C.; Roeckl, E.; Schaedel, M. [GSI, Darmstadt (Germany); Blazhev, A. [GSI, Darmstadt (Germany); Univ. Sofia (Bulgaria); Faestermann, T. [Technische Universitaet Muenchen (Germany); Janas, Z.; Karny, M.; Plochocki, A.; Zylicz, J. [University of Warsaw (Poland); Jungclaus, A. [Universidad Autonoma de Madrid, Departamento de Fisica Teorica (Spain); La Commara, M.; Romoli, M. [Universita ' ' Federico II' ' and INFN, Napoli (Italy); Mukha, I. [GSI, Darmstadt (Germany); Kurchatov Inst., Moscow (Russian Federation); Muralithar, S. [GSI, Darmstadt (Germany); Nuclear Science Center, New Delhi (India)
2006-08-15
The {beta}-decay of {sup 105}Sn was re-investigated at the ISOL facility of GSI Darmstadt by using a total absorption spectrometer. The experimental results include the half-life and {beta}-delayed proton branching ratio of 32.7(5) s and 1.1(4).10{sup -4}, respectively, and the contribution of electron capture to the {sup 105}Sn decay of 0.420(35). The Gamow-Teller strength distribution peaking at 3.6 MeV was measured, yielding a summed Gamow-Teller strength of 3.0(4). The latter data are discussed in comparison with shell-model predictions based on an empirical interaction. (orig.)
Effect of Tensor Correlations on Gamow-Teller States in 90Zr and 208Pb
Bai, C L; Zhang, H Q; Zhang, X Z; Colò, G; Xu, F R
2008-01-01
The tensor terms of the Skyrme effective interaction are included in the self-consistent Hartree-Fock plus Random Phase Approximation (HF+RPA) model. The Gamow-Teller (GT) strength function of 90Zr and 208Pb are calculated with and without the tensor terms. The main peaks are moved downwards by about 2 MeV when including the tensor contribution. About 10% of the non-energy weighted sum rule is shifted to the excitation energy region above 30 MeV by the RPA tensor correlations. The contribution of the tensor terms to the energy weighted sum rule is given analytically, and compared to the outcome of RPA.
Nabi, Jameel-Un; Fayaz, Muhammad
2016-01-01
Gamow-Teller transitions in isotopes of chromium play a consequential role in the presupernova evolution of massive stars. $\\beta$-decay and electron capture rates on chromium isotopes significantly affect the time rate of change of lepton fraction ($\\dot{Y_{e}}$). Fine-tuning of this parameter is one of the key for simulating a successful supernova explosion. The (anti)neutrinos produced as a result of electron capture and $\\beta$-decay are transparent to stellar matter during presupernova phases. They carry away energy and this result in cooling the stellar core. In this paper we present the calculations of Gamow-Teller strength distributions and (anti)neutrino energy loss rates due to weak interactions on chromium isotopes of astrophysical importance. We compare our results with measured data and previous calculations wherever available.
Gamow-Teller and dipole strength in the {sup 208}Pb(n,p) reaction
Energy Technology Data Exchange (ETDEWEB)
Raywood, K.J.; Long, S.A.; Spicer, B.M.
1997-06-01
Earlier date on the {sup 208}Pb(n.p){sup 208}Tl reaction at 198 MeV has been analysed using the multipole decomposition technique, and the contributions tot he spectra from L=0 and 1 transitions determined. The L=0 cross section has been found to be smaller than values given by the calculations of Macfarlane for Gamow-Teller transitions, using three different forms for the population of single particle states about the Fermi energy. Comparison is made with GT-strength values obtained from a more recent mean field calculation of these populations, and with an older nuclear structure calculation of properties of the lead nuclei. the L=1 strength distribution is also reported. 13 refs., 4 figs.
Role of momentum transfer in the quenching of the Gamow-Teller strength
Energy Technology Data Exchange (ETDEWEB)
Marketin, T.; Martinez-Pinedo, G.; Paar, N.; Vretenar, D. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt, Germany and Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia)
2012-10-20
A recent analysis of (p,n) and (n,p) reaction data from {sup 90}Zr was performed recently, where a significant amount of Gamow-Teller strength was found above the resonance, an energy region previously unreachable by experimental setups. The extracted strengths in the {beta}{sub -} and the {beta}{sub +} channel indicate that approximately 10% of the total strength necessary to satisfy the model independent Ikeda sum rule is missing. One possible source of this discrepancy is the treatment of the isovector spin monopole (IVSM) mode of excitation which has been found to occurr at high excitation energies. Employing the relativistic Hartree-Bogoliubov (RHB) model and the protonneutron relativistic quasiparticle random phase approximation (pn-RQRPA) to calculate the nuclear response, we explore the contribution of the IVSM mode to the total L= 0 strength and apply our results to the available data.
Gamow-Teller response in deformed even and odd neutron-rich Zr and Mo isotopes
Sarriguren, P; Pereira, J
2014-01-01
Beta-decay properties of neutron-rich Zr and Mo isotopes are investigated within a microscopic theoretical approach based on the proton-neutron quasiparticle random-phase approximation. The underlying mean field is described self-consistently from deformed Skyrme Hartree-Fock calculations with pairing correlations. Residual separable particle-hole and particle-particle forces are also included in the formalism. The structural evolution in these isotopic chains including both even and odd isotopes is analyzed in terms of the equilibrium deformed shapes. Gamow-Teller strength distributions, beta-decay half-lives, and beta-delayed neutron-emission probabilities are studied, stressing their relevance to describe the path of the nucleosynthesis rapid neutron capture process.
Gamow-Teller resonances and a separable approximation for Skyrme tensor interactions
Directory of Open Access Journals (Sweden)
Severyukhin A. P.
2012-12-01
Full Text Available A finite rank separable approximation for the quasiparticle random phase approximation (QRPA with Skyrme interactions is applied to study properties of the Gamow-Teller (GT resonances in the neutron-rich Cd isotopes. This approximation enables one to reduce considerably the dimension of matrix that must be diagonalized to perform QRPA calculations in a very large configuration space. Our results from the SGII Skyrme interaction with the tensor interactions and the density-dependent zero-range pairing interaction show that the GT distribution is noticeably modified when the tensor correlations are taken into account. In particular, for 130Cd the dominant peak is moved 3.6 MeV downward and 10% of the GT distribution is shifted to the high excitation energy region near E=50MeV.
Systematics of Gamow-Teller beta decay "Southeast" of Sn-100
Batist, L.; Gorska, M.; Grawe, H.; Janas, Z.; Kavatsyuk, M.; Karny, M.; Kirchner, R.; La Commara, M.; Mukha, I.; Plochocki, A.; Roeckl, E.
2010-01-01
The energy centroids and integrated strengths of Gamow-Teller transitions in the beta(+) and electron-capture decay are analyzed for nuclei whose proton number Z and neutron number N are restricted to 44
Nabi, Jameel-Un; Ishfaq, Mavra
2016-07-01
We calculate Gamow-Teller strength distributions for β β-decay nuclei ^{76}Ge and ^{82}Se using the deformed pn-QRPA model. We use a deformed Nilsson basis and consider pairing correlations within the deformed BCS theory. Ground state correlations and two-particle and two-hole mixing states were included in our pn-QRPA model. Our calculated strength distributions were compared with experimental data and previous calculation. The total Gamow-Teller strength and centroid placement calculated in our model compares well with the measured value. We calculate β-decay and positron capture rates on ^{76}Ge and ^{82}Se in supernovae environments and compare them to those obtained from experimental data and previous calculation. Our study shows that positron capture rates command the total weak rates at high stellar temperatures. We also calculate energy rates of β-delayed neutrons and their emission probabilities.
Energy Technology Data Exchange (ETDEWEB)
Poirier, E
2002-12-01
Nuclei with A {approx} 70 along the N=Z line are known to be the scene of phenomena closely related to the nuclear deformation and are of particular interest since theoretical mean field calculations predict that a large part of the Gamow-Teller resonance might be located below the ground state of the mother nucleus and then be accessible through {beta}-decay studies. These results have shown the effect of the shape of the ground state on the intensity of the Gamow-Teller strength. Thus, the experimental determination, through {delta}-decay, of the Gamow-Teller strength distribution and the comparison to the theoretical predictions allow to pin down the quadrupolar deformation parameter of the ground state of the parent nucleus. In order to study the neutron deficient isotopes of krypton (A=72,73,74,75) and strontium (A=76,77,78) and to establish the {beta}-strength on the full energy range, a new total absorption spectrometer (TAgS) has been built in the frame of an international collaboration and installed at the (SOLDE/CERN mass separator. For the data analysis, the response function R of the spectrometer has been calculated by means of Monte-Carlo simulations, based on the GEANT4 code, and of a statistical description of the level scheme in the daughter nucleus. The {beta}-feeding distribution has been obtained from experimental spectra through a method based on Bayes theorem and then converted into Gamow-Teller strength. The results coming from the {sup 74}Kr decay analysis allow to describe the ground state of such a nucleus as the coexistence of an oblate shape and of a prolate shape. In the case of {sup 76}Sr, the experimental Gamow-Teller strength distribution strongly indicates a prolate deformation. (author)
Gamow-Teller Resonance of 90Zr in a Relativistic Approach
Institute of Scientific and Technical Information of China (English)
马中玉; 陈宝秋
2003-01-01
We establish the formalism of nuclear spin-isospin excitations, especially the Gamow-Teller resonance in a fully consistent relativistic random-phase approximation. A relativistic form of the Landau-Migdal parameter g′ is adopted as a residual spin-isospin correlation force. In the non-relativistic limit it reproduces the excitation energy of the giant Gamow-Teller resonance state obtained in the non-relativistic model. The Gamow-Teller resonance for finite nuclei is investigated in a relativistic approach for the first time. It is found that the Ikeda sum rule of90Zr is quenched about 8% in the Hartree as well as the correlated strengths due to the poles of the negative Dirac states at energies above 1 GeV.
Comparison of Gamow-Teller strengths in the random phase approximation
Nabi, Jameel-Un
2012-01-01
The Gamow-Teller response is astrophysically important for a number of nuclides, particularly around iron. The random phase approximation (RPA) is an efficient way to generate strength distributions. In order to better understand both theoretical systematics and uncertainties, we compare the Gamow-Teller strength distributions for a suite of nuclides and for a suite of interactions, including semi-realistic interactions in the $1p$-$0f$ space with the RPA and a separable multi-shell interaction in the quasi-particle RPA. We also compare with experimental results for GT$_-$ on ${54}$Fe.
Pseudospin Symmetry and Forbidden Magnetic Dipole and Gamow-Teller Transitions
Ginocchio, Joseph
1999-10-01
Recently it has been shown that pseudospin symmetry has its origins in a relativistic symmetry of the Dirac Hamiltonian[1]. Using this symmetry we relate single - nucleon relativistic magnetic moments of states in a pseudospin doublet to the relativistic magnetic dipole transitions between the states in the doublet, and we relate single - nucleon relativistic Gamow - Teller transitions within states in the doublet. We apply these relationships to the Gamow - Teller transitions from ^39Ca to its mirror nucleus ^39K [2] and to the systematics of forbidden magnetic dipole transitions. 1. J. N. Ginocchio and A. Leviatan Phys. Lett. B 425, 1 (1998). 2. J. N. Ginocchio Phys. Rev. C 59, 2487 (1999).
Gamow-Teller (GT$\\pm$) strength distributions of $^{56}Ni$ for ground and excited states
Nabi, Jameel-Un; Sajjad, Muhammad
2016-01-01
Gamow-Teller (GT) transitions play an important and consequential role in many astrophysical phenomena. These include, but are not limited to, electron and positron capture rates which determine the fate of massive stars and play an intricate role in the dynamics of core collapse. These $GT_{\\pm}$ transitions rates are the significant inputs in the description of supernova explosions. $GT_{\\pm}$ strength function values are sensitive to the $^{56}Ni$ core excitation in the middle \\textit{pf}-shell region and to the size of the model space as well. We used the pn-QRPA theory for extracting the GT strength for ground and excited states of $^{56}Ni$. We then used these GT strength distributions to calculate the electron \\textit{and} positron capture rates which show differences with the earlier calculations. One curious finding of this paper is our enhanced electron capture rates on $^{56}Ni$ at presupernova temperatures. These differences need to be taken into account for the modeling of the early stages of Typ...
DIRECT PROTON DECAY FROM THE GAMOW-TELLER RESONANCE IN BI-208
AKIMUNE, H; DAITO, [No Value; FUJITA, Y; FUJIWARA, M; GREENFIELD, MB; HARAKEH, MN; INOMATA, T; JANECKE, J; KATORI, K; NAKAYAMA, S; SAKAI, H; SAKEMI, Y; TANAKA, M; YOSOI, M
1995-01-01
Spin-isospin excitations in Bi-208 have been investigated using the Pb-208(He-3,t)Bi-208 reaction at and near theta approximate to 0 degrees at E(He-3)=450 MeV. The microscopic structure of the Gamow-Teller resonance (GTR), the isobaric analog state (IAS), and the spin-flip dipole (Delta L = 1) reso
On direct proton decay of the Gamow-Teller giant resonance
Directory of Open Access Journals (Sweden)
Urin M.H.
2012-12-01
Full Text Available The semi-microscopic approach to the description of giant resonances in medium-heavy mass closed-shell nuclei is implemented to treat partial probabilities of direct-proton decay of the Gamow-Teller giant resonance (GTGR in 208Bi. The corresponding experimental data are reasonably explained.
Shell model description of Gamow-Teller strengths for $^{42}$Ti, $^{46}$Cr, $^{50}$Fe and $^{54}$Ni
Kumar, Vikas; Hirsch, Jorge G
2015-01-01
A systematic shell model description of the experimental Gamow-Teller transition strength distributions in $^{42}$Ti, $^{46}$Cr, $^{50}$Fe and $^{54}$Ni is presented. These transitions have been recently measured via $\\beta$ decay of these $T_z$=-1 nuclei, produced in fragmentation reactions at GSI and also with ($^3${He},$t$) charge-exchange (CE) reactions corresponding to $T_z = + 1$ to $T_z = 0$ carried out at RCNP-Osaka. The calculations are performed in the $pf$ model space, using the GXPF1a and KB3G effective interactions. Qualitative agreement is obtained for the individual transitions, while the calculated summed transition strengths closely reproduce the observed ones.
Nabi, Jameel-Un; Ishfaq, Mavra; Böyükata, Mahmut; Riaz, Muhammad
2017-10-01
At finite temperatures (≥ 107K), 76Se is abundant in the core of massive stars and electron capture on 76Se has a consequential role to play in the dynamics of core-collapse. The present work may be classified into two main categories. In the first phase we study the nuclear structure properties of 76Se using the interacting boson model-1 (IBM-1). The IBM-1 investigations include the energy levels, B (E 2) values and the prediction of the geometry. We performed the extended consistent-Q formalism (ECQF) calculation and later the triaxial formalism calculation (constructed by adding the cubic term to the ECQF). The geometry of 76Se can be envisioned within the formalism of the potential energy surface based on the classical limit of IBM-1 model. In the second phase, we reconfirm the unblocking of the Gamow-Teller (GT) strength in 76Se (a test case for nuclei having N > 40 and Z < 40). Using the deformed pn-QRPA model we calculate GT transitions, stellar electron capture cross section (within the limit of low momentum transfer) and stellar weak rates for 76Se. The distinguishing feature of our calculation is a state-by-state evaluation of stellar weak rates in a fully microscopic fashion. Results are compared with experimental data and previous calculations. The calculated GT distribution fulfills the Ikeda sum rule. Rates for β-delayed neutrons and emission probabilities are also calculated. Our study suggests that at high stellar temperatures and low densities, the β+-decay on 76Se should not be neglected and needs to be taken into consideration along with electron capture rates for simulation of presupernova evolution of massive stars.
Zegers, R. G. T.; Brown, E. F.; Akimune, H.; Austin, Sam M.; Van den Berg, A. M.; Brown, B. A.; Chamulak, D. A.; Fujita, Y.; Fujiwara, M.; Gales, S.; Harakeh, M. N.; Hashimoto, H.; Hayami, R.; Hitt, G. W.; Itoh, M.; Kawabata, T.; Kawase, K.; Kinoshita, M.; Nakanishi, K.; Nakayama, S.; Okumura, S.; Shimbara, Y.; Uchida, M.; Ueno, H.; Yamagata, T.; Yosoi, M.
2008-01-01
The Gamow-Teller strength for the transition from the ground state of (13)C to the T=1/2,J(pi)=3/2(-) excited state at 3.51 MeV in (13)N is extracted via the (13)C((3)He,t) reaction at 420 MeV. In contrast to results from earlier (p,n) studies on (13)C, a good agreement with shell-model calculations
Gamow-Teller and Fermi decay of N=Z nuclei above A=70
Dessagne, P; Axelsson, L; Blank, B; García-Borge, M J; Bruce, A M; Catford, W N; Chandler, C; Clark, R M; Cullen, D M; Czajkowski, S; Daugas, J M; Fleury, A; Frankland, J D; Garces-Narro, J; Gelletly, W; Giovinazzo, J; Greenhalgh, B J; Grzywacz, R; Harder, M K; Huck, A; Jokinen, A; Jones, K L; Kelsall, N; Knipper, A; Kszczot, T; Lewitowicz, M; Longour, C; Miehé, C; Page, R D; Pearson, C J; Piqueras, I; Ramdhane, M; Rauch, V; Reed, A T; Regan, P H; Sorlin, O; Tengblad, O; Wadsworth, R
1999-01-01
The study of the beta decay of some N=Z nuclei in the A=70 mass range have been performed using the GANIL and CERN/ISOLDE facilities. The fast decays of three T/sub x/=0 odd-odd nuclei have been measured for the first time which extend the number of superallowed transitions. Information has been obtained on the Gamow Teller strength distribution in the beta /sup +/-EC decay of two even-even N=Z isotopes /sup 76/Sr and /sup 72/Kr. Results are compared with theoretical predictions giving indication about the shape of the ground state of the parent nucleus. (17 refs).
Gamow-Teller and Fermi Decay of N=Z Nuclei Above A=70
Energy Technology Data Exchange (ETDEWEB)
Dessagne, Ph.; Applebe, D.; Axelsson, L.; Blank, B.; Borge, M.J.G.; Bruce, A.M.; Catford, W.N.; Chandler, C.; Clark, R.M.; Cullen, D.M.; Czajkowski, S.; Daugas, J.M.; Fleury, A.; Frankland, L.; Garces Narro, J.; Gelletly, W.; Giovinazzo, J.; Greenhalgh, B.; Grzywacz, R.; Harder, M.; Huck, A.; Jokinen, A.; Jones, K.L.; Kelsall, N.; Knipper, A.; Kszczot, T.; Lewitowicz, M.; Longour, C.; Miehe, C.; Page, R.D.; Pearson, C.J.; Piqueras, I.; Ramdhane, M.; Rauch, V.; Reed, A.T.; Regan, P.H.; Sorlin, O.; Tengblad, O.; Wadsworth, R.
1999-12-31
The study of the {beta} decay of some N=Z nuclei in the A=70 mass range have been performed using the GANIL and CERN/ISOLDE facilities. The fast decays of three T{sub z}=0 odd-odd nuclei have been measured for the first time which extend the number of superallowed transitions. Information has been obtained on the Gamow Teller strength distribution in the {beta}+-EC decay of two even-even N=Z isotopes {sup 76}Sr and {sup 72}Kr. Results are compared with theoretical predictions giving indication about the shape of the ground state of the parent nucleus.
Zegers, R G T; Akimune, H; Austin, Sam M; Berg, A M van den; Brown, B A; Chamulak, D A; Fujita, Y; Fujiwara, M; Gal`es, S; Harakeh, M N; Hashimoto, H; Hayami, R; Hitt, G W; Itoh, M; Kawabata, T; Kawase, K; Kinoshita, M; Nakanishi, K; Nakayama, S; Okamura, S; Shimbara, Y; Uchida, M; Ueno, H; Yamagata, T; Yosoi, M
2007-01-01
The Gamow-Teller strength for the transition from the ground state of 13C to the T=1/2, J^pi=3/2- excited state at 3.51 MeV in 13N is extracted via the 13C(3He,t) reaction at 420 MeV. In contrast to results from earlier (p,n) studies on 13C, a good agreement with shell-model calculations and the empirical unit cross section systematics from other nuclei is found. The results are used to study the analog 13N(e-,neutrino)13C reaction, which plays a role in the pre-explosion convective phase of type Ia supernovae. Although the differences between the results from the (3He,t) and (p,n) data significantly affect the deduced electron-capture rate and the net heat-deposition in the star due to this transition, the overall effect on the pre-explosive evolution is small.
Energy Technology Data Exchange (ETDEWEB)
Anderson, B.D.; Baldwin, A.R.; Baumann, P.; Brown, B.A.; Didierjean, F.; Foster, C.C.; Garcia, L.A.; Huck, A.; Knipper, A.; Madey, R.; Manley, D.M.; Marguier, G.; Ramdhane, M.; Ravn, H.; Richard-Serre, C.; Walter, G.; Watson, J.W. [Department of Physics and Center for Nuclear Research, Kent State University, Kent, Ohio 44242 (United States)]|[Centre de Recherches Nucleaires, Universite Louis Pasteur, Strasbourg, France and the ISOLDE Collaboration]|[National Superconducting Cyclotron Laboratory and Department of Physics, Michigan State University, East Lansing, Michigan 48824 (United States)]|[Indiana University Cyclotron Facility, Bloomington, Indiana 47408 (United States)]|[Department of Physics, Hampton University, Hampton, Virginia 23668 (United States)]|[Institut de Physique Nucleaire, Universite Claude Bernard, Villeurbanne, France and the ISOLDE Collaboration]|[ISOLDE Collaboration, CERN, Geneva (Switzerland)]|[ISOLDE Collaboration, CERN and IN2P3, Geneva (Switzerland)
1996-08-01
Gamow-Teller (1{sup +}) strength was studied in {sup 38}K with the analog reactions {sup 38}Ar({ital p},{ital n}){sup 38}K and {sup 38}Ca({beta}{sup +}){sup 38}K. The ({ital p},{ital n}) reaction was performed at 135 MeV using the beam swinger facility at the Indiana University Cyclotron Facility. Excitation-energy spectra were measured at 15 angles between 0{degree} and 63{degree}. Neutron energies were measured by the time-of-flight method using a large-volume plastic scintillator array at a flight path of 131.0 m. The overall energy resolution was 280 keV. Gamow-Teller (GT) strength was extracted from the measured angular distributions to discrete 1{sup +} final states. The {beta}-decay experiment was performed with the ISOLDE on-line mass separator facility at CERN. The {beta}-decay branching ratios were determined by observing the delayed {gamma} decays of {sup 38}K. These decay measurements provide an increased sensitivity over earlier measurements and are able to extract transitions down to {approximately} 10{sup {minus}4} of the strongest branches. The {ital B}(GT) values obtained from the two experiments are generally in good agreement, except for the transition to the first 1{sup +} state at 0.46 MeV, which is observed to be much weaker in the ({ital p},{ital n}) measurements. The {beta}-decay measurements provide good resolution and high sensitivity while the ({ital p},{ital n}) measurements extend the {beta}-decay measurements to higher excitation energies. The summed {ital B}(GT) strength is {approximately}50{percent} of the simple Ikeda sum rule. The distribution of GT strength is in reasonable agreement with that predicted from a shell-model calculation using {open_quote}{open_quote}effective{close_quote}{close_quote} GT operators. {copyright} {ital 1996 The American Physical Society.}
Bhattacharya; Goodman; Raghavan; Palarczyk; Garcia; Rapaport; van Heerden IJ; Zupranski
2000-11-20
We report a 0 degrees 176Yb(p,n)176Lu measurement at IUCF where we used 120 and 160 MeV protons and the energy dependence method to determine Gamow-Teller (GT) matrix elements relative to the model independent Fermi matrix element. The data show that there is an isolated concentration of GT strength in the low-lying 1(+) states making the proposed Low Energy Neutrino Spectroscopy detector (based on neutrino captures on 176Yb) sensitive to pp and 7Be neutrinos and a promising detector to resolve the solar neutrino problem.
Nabi, Jameel-Un
2012-01-01
This paper reports on the microscopic calculation of ground and excited states Gamow-Teller (GT) strength distributions, both in the electron capture and electron decay direction, for $^{54,55,56}$Fe. The associated electron and positron capture rates for these isotopes of iron are also calculated in stellar matter. These calculations were recently introduced and this paper is a follow-up which discusses in detail the GT strength distributions and stellar capture rates of key iron isotopes. The calculations are performed within the framework of the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory. The pn-QRPA theory allows a microscopic \\textit{state-by-state} calculation of GT strength functions and stellar capture rates which greatly increases the reliability of the results. For the first time experimental deformation of nuclei are taken into account. In the core of massive stars isotopes of iron, $^{54,55,56}$Fe, are considered to be key players in decreasing the electron-to-baryon ...
Nabi, Jameel-Un; 10.1103/PhysRevC.76.055803
2011-01-01
Gamow-Teller (GT) strength transitions are an ideal probe for testing nuclear structure models. In addition to nuclear structure, GT transitions in nuclei directly affect the early phases of Type Ia and Type-II supernovae core collapse since the electron capture rates are partly determined by these GT transitions. In astrophysics, GT transitions provide an important input for model calculations and element formation during the explosive phase of a massive star at the end of its life-time. Recent nucleosynthesis calculations show that odd-odd and odd-A nuclei cause the largest contribution in the rate of change of lepton-to-baryon ratio. In the present manuscript, we have calculated the GT strength distributions and electron capture rates for odd-odd nucleus 50V by using the pn-QRPA theory. At present 50V is the first experimentally available odd-odd nucleus in fp-shell nuclei. We also compare our GT strength distribution with the recently measured results of a 50V(d,2He)50Ti experiment, with the earlier work ...
Adachi, Tatsuya; Fujita, Y; von Brentano, P; Lisetskiy, AF; Berg, G.P.A.; Fransen, C; De Frenne, D; Fujita, H; Fujita, K; Hatanaka, K; Honma, M; Jacobs, E; Kamiya, J; Kawase, K; Mizusaki, T; Nakanishi, K; Negret, A; Otsuka, T; Pietralla, N; Popescu, Lucia; Sakemi, Y; Shimbara, Y; Shimizu, Y; Tameshige, Y; Tamii, A; Uchida, M; Wakasa, T; Yosoi, M; Zell, KO
2006-01-01
The Gamow-Teller (GT) transition strengths in fp-shell nuclei are important parameters in presupernova models. A high-energy-resolution (He-3,t) experiment was performed on the T-z=1 nucleus Ti-46 at 0(degrees) and at an intermediate incident energy of 140 MeV/nucleon for the study of precise GT tra
Grodner, E; Gadea, A; Sarriguren, P; Lenzi, S M; Grebosz, J; Valiente-Dobón, J J; Algora, A; Górska, M; Regan, P H; Rudolph, D; de Angelis, G; Agramunt, J; Alkhomashi, N; Amon Susam, L; Bazzacco, D; Benlliure, J; Benzoni, G; Boutachkov, P; Bracco, A; Caceres, L; Cakirli, R B; Crespi, F C L; Domingo-Pardo, C; Doncel, M; Dombrádi, Zs; Doornenbal, P; Farnea, E; Ganioğlu, E; Gelletly, W; Gerl, J; Gottardo, A; Hüyük, T; Kurz, N; Leoni, S; Mengoni, D; Molina, F; Morales, A I; Orlandi, R; Oktem, Y; Page, R D; Perez, D; Pietri, S; Podolyák, Zs; Poves, A; Quintana, B; Rinta-Antila, S; Rubio, B; Nara Singh, B S; Steer, A N; Verma, S; Wadsworth, R; Wieland, O; Wollersheim, H J
2014-08-29
Search for a new kind of superfluidity built on collective proton-neutron pairs with aligned spin is performed studying the Gamow-Teller decay of the T=1, J(π)=0+ ground state of (62)Ge into excited states of the odd-odd N=Z nucleus (62)Ga. The experiment is performed at GSI Helmholtzzentrum für Shwerionenforshung with the (62)Ge ions selected by the fragment separator and implanted in a stack of Si-strip detectors, surrounded by the RISING Ge array. A half-life of T1/2=82.9(14) ms is measured for the (62)Ge ground state. Six excited states of (62)Ga, populated below 2.5 MeV through Gamow-Teller transitions, are identified. Individual Gamow-Teller transition strengths agree well with theoretical predictions of the interacting shell model and the quasiparticle random phase approximation. The absence of any sizable low-lying Gamow-Teller strength in the reported beta-decay experiment supports the hypothesis of a negligible role of coherent T=0 proton-neutron correlations in (62)Ga.
Fujiwara, M; Akimune, H; van den Berg, AM; Cribier, M; Daito, [No Value; Ejiri, H; Fujimura, H; Fujita, Y; Goodman, CD; Hara, K; Harakeh, MN; Ihara, E; Ishikawa, T; Janecke, J; Kawabata, T; Raghavan, RS; Schwarz, K; Tanaka, M; Yamanaka, T; Yosoi, M; Zegers, RGT
2000-01-01
Discrete Gamow-Teller (GT) transitions Yb-176 --> Lu-176 at low excitation energies have been measured via the (He-3, t) reaction at 450 MeV and at 0 degrees. For Yb-176, two low-lying states are observed, setting low thresholds Q(nu) = 301 and 445 keV for neutrino (nu) capture. Capture rates estima
Nabi, Jameel-Un
2011-02-01
This paper reports on the microscopic calculation of ground and excited states Gamow-Teller (GT) strength distributions, both in the electron capture and electron decay direction, for 54,55,56Fe. The associated electron and positron capture rates for these isotopes of iron are also calculated in stellar matter. These calculations were recently introduced and this paper is a follow-up which discusses in detail the GT strength distributions and stellar capture rates of key iron isotopes. The calculations are performed within the framework of the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory. The pn-QRPA theory allows a microscopic state-by-state calculation of GT strength functions and stellar capture rates which greatly increases the reliability of the results. For the first time experimental deformation of nuclei are taken into account. In the core of massive stars isotopes of iron, 54,55,56Fe, are considered to be key players in decreasing the electron-to-baryon ratio ( Y e ) mainly via electron capture on these nuclide. The structure of the presupernova star is altered both by the changes in Y e and the entropy of the core material. Results are encouraging and are compared against measurements (where possible) and other calculations. The calculated electron capture rates are in overall good agreement with the shell model results. During the presupernova evolution of massive stars, from oxygen shell burning stages till around end of convective core silicon burning, the calculated electron capture rates on 54Fe are around three times bigger than the corresponding shell model rates. The calculated positron capture rates, however, are suppressed by two to five orders of magnitude.
Nabi, Jameel-Un; Sajjad, Muhammad
2007-11-01
Gamow-Teller (GT) strength transitions are an ideal probe for testing nuclear structure models. In addition to nuclear structure, GT transitions in nuclei directly affect the early phases of Type Ia and Type-II supernovae core collapse since the electron capture rates are partly determined by these GT transitions. In astrophysics, GT transitions provide an important input for model calculations and element formation during the explosive phase of a massive star at the end of its life-time. Recent nucleosynthesis calculations show that odd-odd and odd-A nuclei cause the largest contribution in the rate of change of lepton-to-baryon ratio. In the present manuscript, we have calculated the GT strength distributions and electron capture rates for odd-odd nucleus V50 by using the pn-QRPA theory. At present V50 is the first experimentally available odd-odd nucleus in fp-shell nuclei. We also compare our GT strength distribution with the recently measured results of a V50(d, He2)Ti50 experiment, with the earlier work of Fuller, Fowler, and Newman (referred to as FFN) and subsequently with the large-scale shell model calculations. One curious finding of the paper is that the Brink's hypothesis, usually employed in large-scale shell model calculations, is not a good approximation to use at least in the case of V50. SNe Ia model calculations performed using FFN rates result in overproduction of Ti50, and were brought to a much acceptable value by employing shell model results. It might be interesting to study how the composition of the ejecta using presently reported QRPA rates compare with the observed abundances.
Energy Technology Data Exchange (ETDEWEB)
Siebels, B.; Gorringe, T.P.; Alford, W.P.; Bauer, J.; Evans, J.; El-Kateb, S.; Jackson, K.P.; Trudel, A.; Yen, S. [Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506 (United States)]|[Department of Physics, University of Western Ontario, London, Ontario, N6A 3K7 (Canada)]|[TRIUMF, 4004 Wesbrook Mall, Vancouver, V6T 2A3 (Canada)]|[Department of Physics, Simon Fraser University, Vancouver, British Columbia, V5A 1S6 (Canada)]|[King Fahd University of Petroleum and Minerals, Dhahram (Saudi Arabia)
1995-09-01
We report measurements of the {sup 23}Na({ital n},{ital p}) differential cross section at an incident energy of 198 MeV and angles from 0{degree} to 24{degree} using the TRIUMF Charge Exchange Facility. From these data we determine Gamow-Teller (GT) transition probabilities to low lying 1/2{sup +}, 3/2{sup +}, and 5/2{sup +} {sup 23}Ne states and the GT{sup +} strength distribution up to 25 MeV excitation energy. The values of B{sub GT}{sup +} to discrete states, and the GT{sup +} strength below 10 MeV, are found to be in reasonable agreement with a full 1{ital s}-0{ital d} shell model calculation with a normalization factor of about 0.74. The GT{sup +} strength above 10 MeV suggests the removal of strength from lower to higher excitation energies. We also compare the {sup 23}Na({ital n},{ital p}) data with {sup 23}Na({mu}{sup {minus}},{nu}) data and find agreement between the values of B{sub GT}{sup +} to discrete levels extracted from the ({ital n},{ital p}) and ({mu}{sup {minus}},{nu}) reactions. The general consistency of the ({ital n},{ital p}) and ({mu}{sup {minus}},{nu}) data, and the full 1{ital s}-0{ital d} shell model calculation, give confidence in a recent extraction of the weak pseudoscalar coupling from {mu}{sup {minus}} capture on {sup 23}Na. Finally, using both {beta}{sup {minus}}-decay and {mu}{sup {minus}} capture data, we obtain unit cross sections from the {sup 23}Na({ital n},{ital p}) measurement.
Gamow-Teller strength in the ( p , n ) reaction at 136 MeV on sup 20 Ne, sup 24 Mg, and sup 28 Si
Energy Technology Data Exchange (ETDEWEB)
Anderson, B.D.; Tamimi, N.; Baldwin, A.R.; Elaasar, M.; Madey, R.; Manley, D.M.; Mostajabodda' vati, M.; Watson, J.W.; Zhang, W.M. (Department of Physics, Kent State University, Kent, Ohio 44242 (USA)); Foster, C.C. (Indiana University Cyclotron Facility, Bloomington, Indiana 47408 (USA))
1991-01-01
Gamow-Teller (GT) strength distributions were studied in the ({ital p},{ital n}) reaction at 136 MeV on the self-conjugate {ital s}-{ital d} shell nuclei {sup 20}Ne, {sup 24}Mg, and {sup 28}Si. The measurements were performed in two separate experiments with the beam-swinger neutron time-of-flight facility at the Indiana University Cyclotron Facility. The flight paths were 91 and 131 m, respectively, for the two experiments. The neutrons were detected in large-volume plastic-scintillation detectors. The overall time resolutions were about 825 ps; this provided energy resolutions from 300 to 400 keV. GT strength was identified as {Delta}{ital l}=0 contributions in transitions to discrete final states and also in the background and continuum. The 0{degree}, {Delta}l=0 cross sections were converted to {ital B}(GT) units using a universal'' conversion formula calibrated to ({ital p},{ital n}) reactions on other even-even {ital s}-{ital d} shell nuclei. The resulting {ital B}(GT) distributions were compared with full {ital s}-{ital d} shell-model predictions. The distribution for {sup 24}Mg is described well, but the distributions for {sup 20}Ne and {sup 28}Si are described poorly. The total {ital B}(GT) strength observed in discrete states (up to 12 MeV of excitation) for each reaction is 65{plus minus}10 % of that predicted. If one considers {ital B}(GT) strength observed in the continuum above a calculated quasi-free-scattering background, the strength increases to 70--100 % of that predicted. If one considers {ital B}(GT) strength in an analysis of the full continuum (up to {similar to}20 MeV), the entire amount predicted may be observed. These results are consistent with that observed in other light nuclei.
Martini, M; Goriely, S
2014-01-01
The charge-exchange excitations in nuclei are studied within the fully self-consistent proton-neutron quasiparticle random-phase approximation using the finite-range Gogny interaction. No additional parameters beyond those included in the effective nuclear force are included. Axially symmetric deformations are consistently taken into account, both in the description of the ground states and spin-isospin excitations. We focus on the isobaric analog and Gamow-Teller resonances. A comparison of the predicted strength distributions to the existing experimental data is presented and the role of nuclear deformation analyzed. The Gamow-Teller strength is used to estimate the beta-decay half-life of nuclei for which experimental data exist. A satisfactory agreement with experimental half-lives is found and justifies the additional study of the exotic neutron-rich N=82, 126 and 184 isotonic chains of relevance for the r-process nucleosynthesis.
Systematics of Gamow-Teller beta decay ''Southeast'' of {sup 100}Sn
Energy Technology Data Exchange (ETDEWEB)
Batist, L. [St. Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Gorska, M.; Grawe, H.; Kirchner, R.; Roeckl, E. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Janas, Z.; Karny, M.; Plochocki, A. [University of Warsaw, Institute of Experimental Physics, Warsaw (Poland); Kavatsyuk, M. [University of Groningen, KVI, AA Groningen (Netherlands); La Commara, M. [University Federico II, Napoli (Italy); INFN-Napoli, Department of Physics (Italy); Mukha, I. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); IFIC, Valencia (Spain)
2010-10-15
The energy centroids and integrated strengths of Gamow-Teller transitions in the {beta}{sup +} and electron-capture decay are analyzed for nuclei whose proton number Z and neutron number N are restricted to 44 {<=}Z{<=} 50 and 50 {<=}N{<=} 58. The analysis is based on data measured both with high-resolution {gamma} -ray spectrometry and total {gamma} -ray absorption techniques. The dependence of the considered quantities on the relative neutron excess are established after taking into account the effects due to the Coulomb interaction and mean-field level occupancies. An extrapolation of this dependence to the lightest known tin isotopes is used to estimate the decay characteristics of {sup 100}Sn and {sup 101}Sn. The values extrapolated for the half-lives of {sup 100}Sn and {sup 101}Sn agree with experimental data. Using the extrapolated values together with shell model predictions, the Q values for the electron-capture decay of {sup 100}Sn is evaluated. The quenching factor for {beta}{sup +} and the electron-capture decay of the nuclei under consideration here is established to be 0.56(2) with a possible weak dependence on N-Z. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Scholl, Clemens
2010-07-07
Excited states in the light nuclei {sup 9}B and {sup 13}C were studied using the ({sup 3}He,t) charge-exchange reaction on {sup 9}Be and {sup 13}C targets. The measurements were performed at the research center for nuclear physics (RCNP) in Osaka, Japan, using the magnetic spectrometer Grand Raiden and the dispersive WS course. The {sup 3}He beam with an energy of 420 MeV was accelerated by the RCNP Ring Cyclotron. The Grand Raiden spectrometer and the WS course allow to study the ({sup 3}He,t) charge-exchange reaction with an energy resolution of around 30 keV, which is one order of magnitude better than measurements with the (p,n) charge-exchange reaction. The high resolution allows to better separate individual states and to determine weak excitation strengths because of low background in the spectra. A total of 19 states in {sup 13}N were studied, and a total of 20 states were observed in {sup 9}B. Of these, 9 states in {sup 13}C and 10 states in {sup 9}B were identified as being excited by a Gamow-Teller transition. Charge-exchange reactions are related to beta-decay, and at zero momentum transfer a simple proportionality exists between the cross-section of the charge-exchange experiment and the Fermi (F) or Gamow-Teller (GT) beta-decay strength. While the Fermi strength B(F) is concentrated in the transition to the isobaric analog state, the Gamow-Teller strength B(GT) is scattered among the excited states. The main aim of the present study is to determine the B(GT) strengths in the nuclei {sup 9}B and {sup 13}N. The only charge-exchange study of {sup 9}B was made 30 years ago with the (p,n) reaction and a resolution of around 300-400 keV. Many states, especially at high excitation energy, could not be resolved by that study. The present work was able to separate many weakly excited states with small decay width at high excitation energies (12-19 MeV) in {sup 9}B and determine the B(GT) strength distribution by using recent high-precision beta-decay data. The
Orrigo, S E A; Rubio, B; Fujita, Y; Blank, B; Gelletly, W; Agramunt, J; Algora, A; Ascher, P; Bilgier, B; Cáceres, L; Cakirli, R B; Fujita, H; Ganioğlu, E; Gerbaux, M; Giovinazzo, J; Grévy, S; Kamalou, O; Kozer, H C; Kucuk, L; Kurtukian-Nieto, T; Molina, F; Popescu, L; Rogers, A M; Susoy, G; Stodel, C; Suzuki, T; Tamii, A; Thomas, J C
2014-06-06
We report the observation of a very exotic decay mode at the proton drip line, the β-delayed γ-proton decay, clearly seen in the β decay of the T_{z}=-2 nucleus ^{56}Zn. Three γ-proton sequences have been observed after the β decay. Here this decay mode, already observed in the sd shell, is seen for the first time in the fp shell. Both γ and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.
Dzhioev, Alan A; Ponomarev, V Yu; Wambach, J; Langanke, K; Martínez-Pinedo, G
2009-01-01
We propose a new method to calculate stellar weak-interaction rates. It is based on the Thermo-Field-Dynamics formalism and allows the calculation of the weak-interaction response of nuclei at finite temperatures. The thermal evolution of the GT$_+$ distributions is presented for the sample nuclei $^{54, 56}$Fe and ~$^{76,78,80}$Ge. For Ge we also calculate the strength distribution of first-forbidden transitions. We show that thermal effects shift the GT$_+$ centroid to lower excitation energies and make possible negative- and low-energy transitions. In our model we demonstrate that the unblocking effect for GT$_+$ transitions in neutron-rich nuclei is sensitive to increasing temperature. The results are used to calculate electron capture rates and are compared to those obtained from the shell model.
Impact of New Gamow-Teller Strengths on Explosive Type Ia Supernova Nucleosynthesis
Mori, Kanji; Kajino, Toshitaka; Suzuki, Toshio; Hidaka, Jun; Honma, Michio; Iwamoto, Koichi; Nomoto, Ken'ichi; Otsuka, Takaharu
2016-01-01
Recent experimental results have confirmed a possible reduction in the GT$_+$ strengths of pf-shell nuclei. These proton-rich nuclei are of relevance in the deflagration and explosive burning phases of Type Ia supernovae. While prior GT strengths result in nucleosynthesis predictions with a lower-than-expected electron fraction, a reduction in the GT$_+$ strength can result in an slightly increased electron fraction compared to previous shell model predictions, though the enhancement is not as large as previous enhancements in going from rates computed by Fuller, Fowler, and Newman based on an independent particle model. A shell model parametrization has been developed which more closely matches experimental GT strengths. The resultant electron-capture rates are used in nucleosynthesis calculations for carbon deflagration and explosion phases of Type Ia supernovae, and the final mass fractions are compared to those obtained using more commonly-used rates.
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Sasano M.
2016-01-01
Full Text Available The charge-exchange (p,n reaction at 220 MeV has been measured to extract the strength distribution of Gamow-Teller transitions from the doubly magic unstable nucleus 132Sn. A recently developed experimental technique of measuring the (p,n reaction in inverse kinematics has been applied to the study of unstable nuclei in the mass region around A∼100 for the first time. We have combined the low-energy neutron detector WINDS and the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory (RIBF. The particle identification plot for the reaction residues obtained by the spectrometer provides the clear separation of the CE reaction channel from other background events, enabling us to identify kinematic curves corresponding the (p, n reaction. Further analysis to reconstruct the excitation energy spectrum is ongoing.
Niu, Y F; Vigezzi, E; Bai, C L; Sagawa, H
2016-01-01
We propose a self-consistent quasi-particle random phase approximation (QRPA) plus quasi-particle-vibration coupling (QPVC) model with Skyrme interactions to describe the width and the line shape of giant resonances in open-shell nuclei, in which the effect of superfluidity should be taken into account in both the ground state and the excited states. We apply the new model to the Gamow-Teller resonance in the superfluid nucleus $^{120}$Sn, including both the isoscalar spin-triplet and the isovector spin-singlet pairing interactions. The strength distribution in $^{120}$Sn is well reproduced and the underlying microscopic mechanisms, related to QPVC and also to isoscalar pairing, are analyzed in detail.
Nuclear structure calculations in $^{20}$Ne with No-Core Configuration-Interaction model
Konieczka, Maciej
2016-01-01
Negative parity states in $^{20}$Ne and Gamow-Teller strength distribution for the ground-state beta-decay of $^{20}$Na are calculated for the very first time using recently developed No-Core Configuration-Interaction model. The approach is based on multi-reference density functional theory involving isospin and angular-momentum projections. Advantages and shortcomings of the method are briefly discussed.
Calculation of delayed-neutron energy spectra in a QRPA-Hauser-Feshbach model
Energy Technology Data Exchange (ETDEWEB)
Kawano, Toshihiko [Los Alamos National Laboratory; Moller, Peter [Los Alamos National Laboratory; Wilson, William B [Los Alamos National Laboratory
2008-01-01
Theoretical {beta}-delayed-neutron spectra are calculated based on the Quasiparticle Random-Phase Approximation (QRPA) and the Hauser-Feshbach statistical model. Neutron emissions from an excited daughter nucleus after {beta} decay to the granddaughter residual are more accurately calculated than in previous evaluations, including all the microscopic nuclear structure information, such as a Gamow-Teller strength distribution and discrete states in the granddaughter. The calculated delayed-neutron spectra agree reasonably well with those evaluations in the ENDF decay library, which are based on experimental data. The model was adopted to generate the delayed-neutron spectra for all 271 precursors.
Ackerman, Thomas P.; Kinne, Stefan A.; Heymsfield, Andrew J.; Valero, Francisco P. J.
1990-01-01
Several aircraft were employed during the FIRE Cirrus IFO in order to make nearly simultaneous observations of cloud properties and fluxes. A segment of the flight data collected on 28 October 1988 during which the NASA Ames ER-2 overflew the NCAR King Air was analyzed. The ER-2 flew at high altitude making observations of visible and infrared radiances and infrared flux and cloud height and thickness. During this segment, the King Air flew just above the cloud base making observations of ice crystal size and shape, local meteorological variables, and infrared fluxes. While the two aircraft did not collect data exactly coincident in space and time, they did make observations within a few minutes of each other. For this case study, the infrared radiation balance of the cirrus layer is of primary concern. Observations of the upwelling 10 micron radiance, made from the ER-2, can be used to deduce the 10 micron optical depth of the layer. The upwelling broadband infrared flux is also measured from the ER-2. At the same time, the upwelling and downwelling infrared flux at the cloud base is obtained from the King Air measurements. Information on cloud microphysics is also available from the King Air. Using this data in conjunction with atmospheric temperature and humidity profiles from local radiosondes, the necessary inputs for an infrared radiative transfer model can be developed. Infrared radiative transfer calculations are performed with a multispectral two-stream model. The model fluxes at the cloud base and at 19 km are then compared with the aircraft observations to determine whether the model is performing well. Cloud layer heating rates can then be computed from the radiation exchange.
Sarriguren, P
2013-01-01
Electron-capture rates at different density and temperature conditions are evaluated for a set of pf-shell nuclei representative of the constituents in presupernova formations. The nuclear structure part of the problem is described within a quasiparticle random-phase approximation based on a deformed Skyrme Hartree-Fock selfconsistent mean field with pairing correlations and residual interactions in particle-hole and particle-particle channels. The energy distributions of the Gamow-Teller strength are evaluated and compared to benchmark shell-model calculations and experimental data extracted from charge-exchange reactions. The model dependence of the weak rates are discussed and the various sensitivities to both density and temperature are analyzed.
Quesada-Moreno, María Mar; Avilés-Moreno, Juan Ramón; Márquez-García, A A; López-González, Juan Jesús
2014-06-01
The behavior of L-cysteine (C3H7NO2S, (2R)-2-amino-3-sulfanylpropanoic acid) in water at different pH values was analyzed both experimentally and theoretically. The behavior was studied at pH values of 5.21 (at this pH, L-cysteine is a zwitterionic species), 1.00 (protonated species), 8.84 (monodeprotonated species), and 13.00 (dideprotonated species). We carried out a vibrational study using nonchiroptical (IR-Raman) and chiroptical (VCD) techniques complemented by quantum chemical calculations. We adopted a dual strategy, as follows. (i) The hybrid density functionals B3LYP and M062X and the ab initio MP2 method were employed, with the same 6-311++G (d,p) basis set, in order to characterize the relative energies and structures of an extensive set of conformers of L-cysteine. The presence of water was included by utilizing the IEF-PCM implicit solvation model. (ii) The vibrational analysis was made using a chirality-sensitive using a chirality-sensitive technique (VCD) and chirality-insensitive techniques (IR, including MIR and FIR, and Raman), especially in aqueous solution. The results obtained theoretically and experimentally were compared in order to deduce the most stable structures at each pH. Moreover, for the first time, the monodeprotonated anion of L-cysteine was detected in aqueous solution by means of IR, Raman and vibrational circular dichroism (VCD). Finally, analysis of the low-frequency region using the IR and Raman techniques was shown to be a very important way to understanding the conformational preference of the zwitterionic species.
Superallowed Gamow-Teller decay of the doubly magic nucleus Sn-100
Hinke, C. B.; Boehmer, M.; Boutachkov, P.; Faestermann, T.; Geissel, H.; Gerl, J.; Gernhaeuser, R.; Gorska, M.; Gottardo, A.; Grawe, H.; Grebosz, J. L.; Kruecken, R.; Kurz, N.; Liu, Z.; Maier, L.; Nowacki, F.; Pietri, S.; Podolyak, Zs; Sieja, K.; Steiger, K.; Straub, K.; Weick, H.; Wollersheim, H. -J.; Woods, P. J.; Al-Dahan, N.; Alkhomashi, N.; Atac, A.; Blazhev, A.; Braun, N. F.; Celikovic, I. T.; Davinson, T.; Dillmann, I.; Domingo-Pardo, C.; Doornenbal, P. C.; de France, G.; Farrelly, G. F.; Farinon, F.; Goel, N.; Habermann, T. C.; Hoischen, R.; Janik, R.; Karny, M.; Kaskas, A.; Kojouharov, I. M.; Kroell, Th; Litvinov, Y.; Myalski, S.; Nebel, F.; Nishimura, S.; Nociforo, C.; Nyberg, J.; Parikh, A. R.; Prochazka, A.; Regan, P. H.; Rigollet, C.; Schaffner, H.; Scheidenberger, C.; Schwertel, S.; Soederstroem, P. -A.; Steer, S. J.; Stolz, A.; Strmen, P.
2012-01-01
The shell structure of atomic nuclei is associated with 'magic numbers' and originates in the nearly independent motion of neutrons and protons in a mean potential generated by all nucleons. During beta(+)-decay, a proton transforms into a neutron in a previously not fully occupied orbital, emitting
The Gamow-Teller resonance in the rare-earth region
Nacher, E; Cano-Ott, D; Taín, J L; Kleinheinz, P; Algora, A; Algora, A; Mta-Atomki, D; Gadea, A; Lnl, L; Batist, L; Döring, J; Kirchner, R
2003-01-01
The nuclei around sup 1 sup 4 sup 6 Gd in the rare-earth region represent the unique case in the nuclide chart. Among these nuclei, the odd-odd N=83 cases are of special interest for different reasons. The three nuclei considered here have two beta-decaying isomers with spins 2 sup - and 9 sup +. These six cases allow to study the B sub G sub T as a function of the number of pi h sub 1 sub 1 sub / sub 2 particles present in the parent nucleus. A second reason for studying these particular nuclei is the fact that in all cases the 2 sup - isomer can be produced cleanly, without contamination from the 9 sup + one. (R.P.)
Reinvestigation of the beta-decay of {sup 110}Mo
Energy Technology Data Exchange (ETDEWEB)
Wang, J.C.; Dendooven, P.; Hankonen, S.; Huikari, J.; Jokinen, A.; Kolhinen, V.S.; Lhersonneau, G.; Nieminen, A.; Peraejaervi, K.; Rinta-Antila, S.; Aeystoe, J. [Department of Physics, University of Jyvaeskylae, FIN-40351, Jyvaeskylae (Finland)
2004-01-01
The beta-decay of the neutron-rich nucleus {sup 110}Mo, separated by the IGISOL on-line mass separator from other fission products, has been investigated by using beta-gamma and gamma-gamma coincidence techniques. The decay scheme of {sup 110}Mo has been revised, including 3 new excited states and 7 new {gamma} transitions in {sup 110}Tc. The {beta}-feedings were measured and log ft values and B(GT) values were deduced based on a Q{sub {beta}}-value from systematics. Three excited 1{sup +} states in {sup 110}Tc fed by spin-flip allowed-unhindered beta transitions were identified. The deduced beta-decay strengths are compared with the Gamow-Teller strength distribution obtained from a macroscopic-microscopic calculation. The role of the asymptotic quantum numbers in the context of the allowed beta-decay is discussed. (orig.)
Nuclear structure calculations for two-neutrino double-beta decay
Sarriguren, P; de Guerra, E Moya
2016-01-01
We study the two-neutrino double-beta decay in 76Ge, 116Cd, 128Te, 130Te, and 150Nd, as well as the two Gamow-Teller branches that connect the double-beta decay partners with the states in the intermediate nuclei. We use a theoretical microscopic approach based on a deformed selfconsistent mean field with Skyrme interactions including pairing and spin-isospin residual forces, which are treated in a proton-neutron quasiparticle random-phase approximation. We compare our results for Gamow-Teller strength distributions with experimental information obtained from charge-exchange reactions. We also compare our results for the two-neutrino double-beta decay nuclear matrix elements with those extracted from the measured half-lives. Both single-state and low-lying-state dominance hypotheses are analyzed theoretically and experimentally making use of recent data from charge-exchange reactions and beta decay of the intermediate nuclei.
Beta-decay properties of Si-25 and P-26
Achouri, L; Aysto, J; Beraud, R; Blank, B; Canchel, G; Czajkowski, S; Dendooven, P; Ensallem, A; Giovinazzo, J; Guillet, N; Honkanen, J; Jokinen, A; Laird, A; Lewitowicz, M; Longour, C; Santos, FD; Perajarvi, K; Stanoiu, M
2004-01-01
The beta-decay properties of the neutron-deficient nuclei Si-25 and P-26 have been investigated at the GANIL/LISE3 facility by means of charged-particle and gamma-ray spectroscopy. The decay schemes obtained and the Gamow-Teller strength distributions are compared to shell-model calculations based o
Beta-decay studies near {sup 100}Sn
Energy Technology Data Exchange (ETDEWEB)
Karny, M.; Janas, Z.; Miernik, K.; Plochocki, A.; Zylicz, J. [University of Warsaw, Institute of Experimental Physics, Warsaw (Poland); Batist, L. [St. Petersburg Nuclear Physics Institute, St. Petersburg (Russian Federation); Banu, A.; Becker, F.; Burkard, K.; Bruechle, W.; Doering, J.; Gorska, M.; Grawe, H.; Kirchner, R.; Mandal, S.; Mazzocchi, C.; Mukha, I.; Plettner, C.; Roeckl, E.; Schaedel, M. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Blazhev, A. [GSI, Darmstadt (Germany); Sofia Univ. (Bulgaria); Faestermann, T. [Technische Universitaet Muenchen, Muenchen (Germany); Jungclaus, A. [Universidad Autonoma de Madrid, Departamento de Fisica Teorica, Madrid (Spain); Kavatsyuk, M.; Kavatsyuk, O. [GSI, Darmstadft (Germany); Taras Shevchenko Kiev National University, Kiev (Ukraine); La Commara, M.; Romoli, M. [Universita ' ' Federico II' ' and INFN Napoli, Dipartimento Scienze Fisiche, Napoli (Italy); Muralithar, S. [GSI, Darmstadt (Germany); Nuclear Science Center, New Delhi (India); Rykaczewski, K. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Schmidt, K. [Continental Teves AG and Co., Frankfurt am Main (Germany); Schwengner, R. [Forschungszentrum Rossendorf, Dresden (Germany)
2005-09-01
The {beta}-decay of {sup 102}Sn was studied by using high-resolution germanium detectors as well as a Total Absorption Spectrometer (TAS). A decay scheme has been constructed based on the {gamma}-{gamma} coincidence data. The total experimental Gamow-Teller strength B{sub GT}{sup exp} of {sup 102}Sn was deduced from the TAS data to be 4.2(9). A search for {beta}-delayed {gamma}-rays of {sup 100}Sn decay remained unsuccessful. However, a Gamow-Teller hindrance factor h = 2.2(3), and a cross-section of about 3nb for the production of {sup 100}Sn in fusion-evaporation reaction between {sup 58}Ni beam and {sup 50}Cr target have been estimated from the data on heavier tin isotopes. The estimated hindrance factor is similar to the values derived for lower shell nuclei. (orig.)
Nuclear Structure Calculations for Two-Neutrino Double-β Decay
Directory of Open Access Journals (Sweden)
P. Sarriguren
2016-01-01
Full Text Available We study the two-neutrino double-β decay in 76Ge, 116Cd, 128Te, 130Te, and 150Nd, as well as the two Gamow-Teller branches that connect the double-β decay partners with the states in the intermediate nuclei. We use a theoretical microscopic approach based on a deformed self-consistent mean field with Skyrme interactions including pairing and spin-isospin residual forces, which are treated in a proton-neutron quasiparticle random-phase approximation. We compare our results for Gamow-Teller strength distributions with experimental information obtained from charge-exchange reactions. We also compare our results for the two-neutrino double-β decay nuclear matrix elements with those extracted from the measured half-lives. Both single-state and low-lying-state dominance hypotheses are analyzed theoretically and experimentally making use of recent data from charge-exchange reactions and β decay of the intermediate nuclei.
Supernova electron capture rates
Martínez-Pinedo, G
1999-01-01
We have calculated the Gamow-Teller strength distributions for the ground states and low lying states of several nuclei that play an important role in the precollapse evolution of supernova. The calculations reproduce the experimental GT distributions nicely. The GT distribution are used to calculate electron capture rates for typical presupernova conditions. The computed rates are noticeably smaller than the presently adopted rates. The possible implications for the supernova evolution are discussed.
Energy Technology Data Exchange (ETDEWEB)
Fynbo, H.O.U.; Borge, M.J.G.; Axelsson, L.; Aeystoe, J.; Bergmann, U.C.; Fraile, L.M.; Honkanen, A.; Hornshoej, P.; Jading, Y.; Jokinen, A.; Jonson, B.; Martel, I.; Mukha, I.; Nilsson, T.; Nyman, G.; Oinonen, M.; Piqueras, I.; Riisager, K.; Siiskonen, T.; Smedberg, M.H.; Tengblad, O.; Thaysen, J.; Wenander, F
2000-09-11
We have measured the beta-decay of {sup 31}Ar with a high granularity setup sensitive to multiparticle decay branches. Two-proton emission is observed from the isobaric analog state in {sup 31}Cl to the four lowest states in {sup 29}P and furthermore from a large number of states fed in Gamow-Teller transitions. The mechanism of two-proton emission is studied via energy and angular correlations between the two protons. In all cases the mechanism is found to be sequential yielding information about states in {sup 30}S up to 8 MeV excitation energy. Improved data on the {beta}-delayed one-proton branches together with the two-proton data provide precise information about the beta-strength distribution up to 15 MeV excitation energy.
Neutrinoless double beta nuclear matrix elements around mass 80 in the nuclear shell-model
Yoshinaga, N.; Higashiyama, K.; Taguchi, D.; Teruya, E.
2015-05-01
The observation of the neutrinoless double-beta decay can determine whether the neutrino is a Majorana particle or not. For theoretical nuclear physics it is particularly important to estimate three types of matrix elements, namely Fermi (F), Gamow-Teller (GT), and tensor (T) matrix elements. In this paper, we carry out shell-model calculations and also pair-truncated shell-model calculations to check the model dependence in the case of mass A=82 nuclei.
Neutrinoless double beta nuclear matrix elements around mass 80 in the nuclear shell-model
Directory of Open Access Journals (Sweden)
Yoshinaga N.
2015-01-01
Full Text Available The observation of the neutrinoless double-beta decay can determine whether the neutrino is a Majorana particle or not. For theoretical nuclear physics it is particularly important to estimate three types of matrix elements, namely Fermi (F, Gamow-Teller (GT, and tensor (T matrix elements. In this paper, we carry out shell-model calculations and also pair-truncated shell-model calculations to check the model dependence in the case of mass A=82 nuclei.
Strange neutral currents in nuclei
Ressell, M T; Aufderheide, M B; Bloom, S D; Resler, D A
1995-01-01
We examine the effects on the nuclear neutral current Gamow-Teller (GT) strength of a finite contribution from a polarized strange quark sea. We perform nuclear shell model calculations of the neutral current GT strength for a number of nuclei likely to be present during stellar core collapse. We compare the GT strength when a finite strange quark contribution is included to the strength without such a contribution. As an example, the process of neutral current nuclear de-excitation via \
Rahman, Muneeb-Ur
2014-01-01
The Gamow-Teller strength distribution function, B(GT), for the odd Z parent $^{51}$V, $N-Z$ =5, up to 30 MeV of excitation energy in the daughter $^{51}$Ti is calculated in the domain of proton-neutron Quasiparticle Random Phase Approximation (pn-QRPA) theory. The pn-QRPA results are compared against other theoretical calculations, (n, p) and high resolution (d, $^{2}$He) reaction experiments. For the case of (d, $^{2}$He) reaction the calibration was performed for $0\\leq E_{j} \\leq 5.0$ MeV, where the authors stressed that within this excitation energy range the $\\Delta L = 0$ transition strength can be extracted with high accuracy for $^{51}$V. Within this energy range the current pn-QRPA total B(GT) strength 0.75 is in good agreement with the (d, $^{2}$He) experiment's total strength of 0.9 $\\pm$ 0.1. The pn-QRPA calculated Gamow-Teller centroid at 4.20 MeV in daughter $^{51}$Ti is also in good agreement with high resolution (d, $^{2}$He) experiment which placed the Gamow-Teller centroid at 4.1 $\\pm$ 0.4 ...
Beta-delayed particle decay of sup 1 sup 7 Ne
Morton, A C; King, J D; Boyd, R N; Bateman, N P T; Buchmann, L; D'Auria, J M; Davinson, T; Dombsky, M; Galster, W; Gete, E; Giesen, U; Iliadis, C; Jackson, K P; Powell, J; Roy, G; Shotter, A
2002-01-01
The beta-delayed particle decay of sup 1 sup 7 Ne has been studied via proton-gamma coincidences, time-of-flight measurements and the ''ratio-cut technique'', allowing cleanly-separated proton and alpha-particle spectra to be obtained. A complete set of proton and alpha branching ratios for the decay of 14 excited states in sup 1 sup 7 F to the ground and excited states of sup 1 sup 6 O and sup 1 sup 3 N has been determined and branching ratios for the beta decay of sup 1 sup 7 Ne to these states have been deduced. From the branching ratios, f sub A t values and reduced Gamow-Teller matrix elements were calculated; no indication of isospin mixing in the isobaric analog state in sup 1 sup 7 F was observed. From the measurement of proton-gamma angular correlations, combined with the selection rules for an allowed beta decay, we obtain J suppi=((1)/(2)) sup - for states at 8.436 and 9.450 MeV and ((3)/(2)) sup - for the state at 10.030 MeV in sup 1 sup 7 F. Probabilities for the beta-delayed p alpha decay to sup...
β-decay studies of the neutron-rich 18,21N isotopes
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
The β-decay studies of neutron-rich 18,21N isotopes have been performed using β-n, β-γ, and β-n-γ coincidence methods. The 18,21N ions were produced by the fragmentation of the 22Ne and 26Mg beams, respectively, on a thick beryllium target. The time of flight of the emitted neutrons following the β-decay of 18,21N was measured by a neutron detector system with wide energy detection range and low-energy detection threshold. In addition, several clover germanium detectors were used to detect the β-delayed γ-rays. The half-lives of the β-decays of 18N and 21N were determined to be (619±2) ms and (82.9±7.5) ms, respec tively. Several new β-delayed neutron groups were observed with a total branching ratio of (6.98±1.46)% and (90.5±4.2)% for 18N and 21N, respectively. The level schemes of 18O and 21O were deduced. The experimental Gamow-Teller β-decay strengths of 18N and 21N to these levels were compared with the shell model calculations.
Energy Technology Data Exchange (ETDEWEB)
Achouri, N.L
2001-09-01
This thesis describes two studies which explore the structure of proton-rich nuclei. The first of these concerned an investigation of the {beta}-delayed charged particle decay of {sup 22}Al. The experiment was carried out using the LISE3 spectrometer at GANIL and permitted the energies of the {beta}-p, {beta}-2p and {beta}-{alpha} transitions together with the corresponding branching ratios to be determined with an improved precision over earlier work. In addition the coincidences with {gamma}-rays were measured for the first time allowing the decay scheme to be reconstructed. Comparison with shell model calculations using the code OXBASH and the mirror nucleus {sup 22}F allowed the spin and parity and the mass of {sup 22}Al g.s. as well as levels in {sup 22}Mg to be deduced. The experimentally determined Gamow Teller strength was found to be in good agreement at low excitation energies with a shell model calcination employing an effective operator. The second study concerned the development of resonant elastic scattering in inverse kinematics as a spectroscopic tool. Extensive simulations were carried out to ascertain the feasibility of such experiments as well as to optimise the set-up. In the context of the later, particular attention was paid to the final resolution. Experiments subsequently undertaken at GANIL with stable and radioactive beams demonstrated that the technique will be a powerful spectroscopic tool for use with radioactive beams with characteristics similar to those that will be furnished by SPIRAL. (author)
Applying generalized non deducibility on compositions (GNDC) approach in dependability
Gnesi, Stefania; Lenzini, Gabriele; Martinelli, Fabio
2004-01-01
This paper presents a framework where dependable systems can be uniformly modeled and dependable properties analyzed within the Generalized Non Deducibility on Compositions (GNDC), a scheme that has been profitably used in definition and analysis of security properties. Precisely, our framework requ
Deducing Energy Consumer Behavior from Smart Meter Data
DEFF Research Database (Denmark)
Ebeid, Emad Samuel Malki; Heick, Rune; Jacobsen, Rune Hylsberg
2017-01-01
The ongoing upgrade of electricity meters to smart ones has opened a new market of intelligent services to analyze the recorded meter data. This paper introduces an open architecture and a unified framework for deducing user behavior from its smart main electricity meter data and presenting...
A new evolutionary theory deduced mathematically from entropy amplification
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
A new evolutionary theory which is able to unite the present evolutionary debates is deduced mathematically from the principle of entropy amplification.It suggests that the extensive evolution is driven by the amplification of entropy,or microscopic diversity,and the biological evolution is driven by the amplification of biodiversity.Forming high hierarchies is the most important way for the amplification and brings out spontaneously three kinds of selection.This theory has some positive cultural meanings.
Photon strength function deduced from photon scattering and neutron capture
Directory of Open Access Journals (Sweden)
Matic A.
2010-10-01
Full Text Available The dipole strength function of 78Se and 196Pt are investigated by two different experimental methods, capture of cold neutrons in 77Se and 195Pt and photon scattering experiments on 78Se and 196Pt. Considering the different ways of excitation, the strength function deduced from the results are expected to agree. The report shows the status of the data analysis and presents first preliminary results.
Energy Technology Data Exchange (ETDEWEB)
Razee, S.S.A.; Staunton, J.B. [Department of Physics, University of Warwick, Coventry (United Kingdom); Ginatempo, B.; Bruno, E. [Dipartimento di Fisica and Unita INFM, Universita di Messina, Messina (Italy); Pinski, F.J. [Department of Physics, University of Cincinnati, OH (United States)
2001-09-24
A theory is presented for describing the effects of annealing magnetic alloys in magnetic fields. It has an ab initio spin-polarized relativistic Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) electronic structure basis and uses the framework of concentration waves. Alloys which would otherwise be soft magnets are found experimentally to develop directional chemical order and significant uniaxial anisotropy when annealed in magnetic fields. Our approach is able to provide a quantitative description of these effects together with the underlying electronic mechanisms. We describe applications to the soft magnetic alloys permalloy and FeCo. (author)
Pande, K.; Schwander, P.; Schmidt, M.; Saldin, D. K.
2014-01-01
We propose a method for deducing time-resolved structural changes in uncrystallized biomolecules in solution. The method relies on measuring the angular correlations of the intensities, when averaged over a large number of diffraction patterns from randomly oriented biomolecules in solution in a liquid solvent. The experiment is somewhat like a pump–probe version of an experiment on small angle X-ray scattering, except that the data expected by the algorithm are not just the radial variation of the averaged intensities. The differences of these correlation functions as measured from a photoexcited and dark structure enable the direct calculation of the difference electron density with a knowledge of only the dark structure. We exploit a linear relation we derive between the difference in these correlation functions and the difference electron density, applicable for small structural changes. PMID:24914159
Pande, K; Schwander, P; Schmidt, M; Saldin, D K
2014-07-17
We propose a method for deducing time-resolved structural changes in uncrystallized biomolecules in solution. The method relies on measuring the angular correlations of the intensities, when averaged over a large number of diffraction patterns from randomly oriented biomolecules in solution in a liquid solvent. The experiment is somewhat like a pump-probe version of an experiment on small angle X-ray scattering, except that the data expected by the algorithm are not just the radial variation of the averaged intensities. The differences of these correlation functions as measured from a photoexcited and dark structure enable the direct calculation of the difference electron density with a knowledge of only the dark structure. We exploit a linear relation we derive between the difference in these correlation functions and the difference electron density, applicable for small structural changes.
Asteroid Sufaces/Regoliths Deduced by Remote Sensing
Price, S.
Resolved imagery on a small number of asteroids provides information about the size, density and surface relief from which inferences may be made regarding their regoliths; Eros Eros is the best studied asteroid in this regard However, remote sensing is necessary to deduce properties for the large majority of objects. These techniques include: spectroscopy and multi-spectral band photometry, which provide clues as to the chemical composition of the surface, infrared (plus visible) radiometry, from which physical bulk and surface properties may be inferred through the derived albedo and thermal inertia, and radar, which permits one to deduce the near surface bulk density. This article reviews what these techniques have revealed about the surface characteristics of asteroids. Asteroids have been classified by the broad emissive properties of the surface as indicated by filter band photometry. Recently, observations from large scale surveys - 2MASS (Denis to a lesser extent) and the Sloan Digital Sky Survey - provided taxonomic classifications for thousands of asteroids. The mineralogy is more secure at higher spectral resolution. Silicates on the surface of asteroids have been inferred from IRAS, ISO and Kuiper Airborne infrared spectra. Infrared radiometry has been used to derive the albedos and diameters of ~2300 asteroids observed by IRAS and MSX. The simplified Standard Thermal Model (STM) works well for main belt asteroids. The model assumes that the asteroid does not rotate and is in instantaneous thermal equilibrium between absorbed sunlight and emitted radiation. Empirical factors for flux enhancement (beaming) and phase function are adopted. There is a dichotomy between large and small asteroids in this database. About 20% of the asteroids with diameters inertia, rotation rate, orientation of the rotation pole, surface roughness and degree of cratering. A complex model is required to account for all the variables. Such a model was developed using full
Neutrino-antineutrino pair emission from thermally excited nuclei in stellar collapse
Dzhioev, Alan A.; Vdovin, A. I.
2014-09-01
We examine the rate of neutrino-antineutrino pair emission by hot nuclei in collapsing stellar cores. The rates are calculated assuming that only allowed charge-neutral Gamow-Teller (GT0) transitions contribute to the decay of thermally excited nuclear states. To obtain the GT0 transition matrix elements, we employ the quasiparticle random phase approximation extended to finite temperatures within the thermo field dynamics formalism. The decay rates and the energy emission rates are calculated for the sample nuclei 56Fe and 82Ge at temperatures relevant to core collapse supernovae.
Neutrino pair emission from thermally excited nuclei in stellar collapse
Dzhioev, Alan A
2013-01-01
We examine the rate of neutrino-antineutrino pair emission by hot nuclei in collapsing stellar cores. The rates are calculated assuming that only allowed charge-neutral Gamow-Teller (GT$_0$) transitions contribute to the decay of thermally excited nuclear states. To obtain the GT$_0$ transition matrix elements, we employ the quasiparticle random phase approximation extended to finite temperatures within the thermo field dynamics formalism. The decay rates and the energy emission rates are calculated for the sample nuclei ${}^{56}$Fe and $^{82}$Ge at temperatures relevant to core collapse supernovae.
Beta decay rates of nuclei with 65 < < 75 for pre-supernova and supernova evolution
Indian Academy of Sciences (India)
Debasish Majumdar; Kamales Kar
2007-03-01
The half-lives are calculated for the - decay process for nuclei in the mass range ∼ 65-75 relevant for the core of a massive star at the late burning stage of stellar evolution and the collapse that leads to supernova explosion. These half-lives and rates are calculated by expressing the - Gamow-Teller decay strengths in terms of smoothed bivariate strength densities. These strength densities are constructed in the framework of spectral averaging theory for two-body nuclear Hamiltonian in a large nuclear shell model space. The method has a natural extension to electron captures as well as weak interaction rates for and -processes.
Neutrinoless Double Beta Nuclear Matrix Elements Around Mass 80 in the Nuclear Shell Model
Yoshinaga, Naotaka; Higashiyama, Koji; Taguchi, Daisuke; Teruya, Eri
The observation of the neutrinoless double-beta decay can determine whether the neutrino is a Majorana particle or not. In its theoretical nuclear side it is particularly important to estimate three types of nuclear matrix elements, namely, Fermi (F), Gamow-Teller (GT), and tensor (T) types matrix elements. The shell model calculations and also the pair-truncated shell model calculations are carried out to check the model dependence on nuclear matrix elements. In this work the neutrinoless double-beta decay for mass A = 82 nuclei is studied. It is found that the matrix elements are quite sensitive to the ground state wavefunctions.
Advance of the perihelion of Mercury deduced from QFT
Chen, Shao-Guang
I deduce the new gravitational formula from the variance in mass of QFT and GR (H05-0029-08, E15-0039 -08, E14-0032-08, D31-0054-10) in the partial differential: f (QFT) = f (GR) = delta∂ (m v)/delta∂ t = f _{P} + f _{C} , f _{P} = m delta∂ v / delta∂ t = - ( G m M /r (2) ) r / r, f _{C} = v delta∂ m / delta∂ t = - ( G m M / r (2) ) v / c (1), f (QFT) is the quasi-Casimir pressure of net virtual neutrinos nuν _{0} flux (after counteract contrary direction nuν _{0}). f (GR) is equivalent to Einstein’s equation, Eq. (1) is a new version of GR and can be solved exactly. Its core content is that the gravity produced by particles collide cannot linear addition, i.e., the nonlinearity of Einstein equation had been replaced by the nonlinearity caused by the variable mass in Eq.(1). Einstein equation can be inferred from Eq.(1) thereby from QFT, but QFT cannot be inferred from Eq.(1) or GR. f (QFT) is essential but f (GR) is phenomenological. Eq.(1) is obtained just by to absorb the essence of corpuscule collided gravitation origin ism proposed by Fatio in 1690 and 1920 Majorana’s experiment concept about gravitational shield effect again fuse with QFT. In my paper ‘QFT’S advance of the perihelion of Mercury, China Science &Technology Overview 125 88-90 (2011)’ QFT gravitational potential U = - G M /r is just the distribution density of net nuν _{0} flux, from SR we again get that: f (QFT) = f _{P} + f _{C}, f _{P} = - m ( delta∂ U / delta∂ r) r / r, f _{C} = - m ( delta∂U / delta∂ r) v / c (2), f _{ P} correspond the change rate of three-dimensional momentum p, f _{C} correspond the change rate of fourth dimensional momentum i m c which show directly as a dissipative force of mass change. According to Eq.(2) the circular motion is instability and elliptic motion is in the auto-stability state. In the fluctuation vacuum a particle with mass M neighbor another particle with mass m, the renormalization mass M and m will be less than that when
Development of Deduced Protein Database Using Variable Bit Binary Encoding
Directory of Open Access Journals (Sweden)
B. Parvathavarthini
2008-01-01
Full Text Available A large amount of biological data is semi-structured and stored in any one the following file formats such as flat, XML and relational files. These databases must be integrated with the structured data available in relational or object-oriented databases. The sequence matching process is difficult in such file format, because string comparison takes more computation cost and time. To reduce the memory storage size of amino acid sequence in protein database, a novel probability-based variable bit length encoding technique has been introduced. The number of mapping of triplet CODON for every amino acid evaluates the probability value. Then, a binary tree has been constructed to assign unique bits of binary codes to each amino acid. This derived unique bit pattern of amino acid replaces the existing fixed byte representation. The proof of reduced protein database space has been discussed and it is found to be reduced between 42.86 to 87.17%. To validate our method, we have collected few amino acid sequences of major organisms like Sheep, Lambda phage and etc from NCBI and represented them using proposed method. The comparison shows that of minimum and maximum reduction in storage space are 43.30% and 72.86% respectively. In future the biological data can further be reduced by applying lossless compression on this deduced data.
Beta decay of the M{sub T}=-1 nucleus {sup 58}Zn studied by selective laser ionization
Energy Technology Data Exchange (ETDEWEB)
Jokinen, A.; Aeystoe, J. [Jyvaeskylae Univ. (Finland). Dept. of Physics; Oinonen, M. [Jyvaeskylae Univ. (Finland). Dept. of Physics]|[EP Division, CERN, CH-1211 Geneve 23 (Switzerland)] [and others; ISOLDE Collaboration
1998-11-01
Beta decay of {sup 58}Zn has been studied for the first time. A new laser ion-source concept has been used to produce mass-separated sources for beta and gamma spectroscopy. The half-life of {sup 58}Zn was determined to be 86(18) ms. Comparisons are made with previous data from charge-exchange reactions. Our Gamow-Teller strength to the 1{sup +} state at 1051 keV excitation in {sup 58}Cu agrees well with the value extracted from a recent ({sup 3}He,t) study. Extensive shell-model calculations are presented. (orig.) With 7 figs., 2 tabs., 33 refs.
Marechal, F; Caballero ontanaya, L
2002-01-01
In the framework of the investigation of the shapes of the ground states of the parent nucleus, we propose to carry out measurements of the complete Gamow-Teller strength distribution for the $^{76-80}$Sr isotopes, with a new Total Absorption Gamma Spectrometer installed on a new beam line. The results will be compared with theoretical calculations based on the mean field approach. A brief report on the IS370 experiment on $^{72-75}$Kr decay, which was recently performed at ISOLDE, will be given and the performance of the sum spectrometer will be presented.
Beta Decays of Isotones with Neutron Magic Number of N=126 and R-process Nucleosynthesis
Suzuki, Toshio; Kajino, Toshitaka; Otsuka, Takaharu
2011-01-01
Beta decays of the isotones with N=126 are studied by shell model calculations taking into account both the Gamow-Teller (GT) and first-forbidden (FF) transitions. The FF transitions are found to be important to reduce the half-lives, by nearly twice to several times, from those by the GT contributions only. Possible implications of the short half-lives of the waiting point nuclei on the r-process nucleosynthesis during the supernova explosions are discussed. A slight shift of the third peak of the element abundances in the r-process toward higher mass region is found.
Influence of electron screening on electron capture rate under high density of stellar interior
Institute of Scientific and Technical Information of China (English)
罗志全; 彭秋和
1996-01-01
The influence of electron screening on electron capture rate in strong screening is investigated, in which the Gamow-Teller resonance transition is considered and the matrix elements for the resonance transition are calculated on the basis of a shell model. The effect of electron screening on electron capture by 56Co is discussed. It is shown that the screening decreases evidently the capture rates in lower temperature and higher density. The effect of electron screening on other nuclear capture rates is estimated. The conclusion derived may influence the research for late stellar evolution and supernova explosion.
2002-01-01
It is proposed to measure the Gamow-Teller strength distribution in the decays of $^{71-75}$Kr and $^{75,76}$Sr using a Total Absorption Gamma-ray Spectrometer (TAGS) based on a large NaI(TI) detector. The $\\gamma$-rays emitted in these decays will be detected in the TAGS in coincidence with positrons and X-rays from electron capture. Measurements of $\\beta$-delayed particles will also be performed in coincidence with the TAGS. Comparison with theoretical calculations based on the mean field approach, Tamm-Dancoff and QRPA method should allow a determination of the shapes of the ground states of these nuclei.
On some singularities of the correlation functions that determine neutrino opacities
Sawyer, R F
1999-01-01
Certain perturbation graphs in the calculation of the effects of the medium on neutrino scattering in supernova matter have a nonintegrable singularity in a physical region. A number of papers have addressed the apparent pathology through an ansatz that invokes higher order (rescattering) effects. Taking the Gamow-Teller terms as an example, we display an expression for the spin-spin correlation function that determines the cross-sections. It is clear from the form that there are no pathologies in the order by order perturbation expansion. Explicit formulae are given for a simple case, leading to an answer that is very different from one given by other authors.
Anderson, K E; Waite, J H
1998-04-01
The zebra mussel is a nonindigenous invader of North American lakes and rivers and one of the few freshwater bivalve molluscs having a byssus--a sclerotized organ used by the mussel for opportunistic attachment to hard surfaces. We have sequenced a foot-specific cDNA whose composite protein sequence was deduced from a series of overlapping but occasionally nonidentical cDNA fragments. The overall deduced sequence matches tryptic peptides from a major byssal precursor protein--Dreissena polymorpha foot protein 1 (Dpfp1). The calculated mass of Dpfp1 is 49 kDa; but this is known to be extensively hydroxylated and O-glycosylated during maturation. Purified native Dpfp1 analyzed using matrix-assisted laser-desorption ionization mass spectrometry with time-of-flight indicates that the protein occurs as at least two size variants with masses of 48.6 and 54.5 kDa. In all probability, the sequence variants reported in this study are related to the larger mass variant. Dpfp1 has a block copolymer-like structure defined by two consensus motifs that are sharply segregated into domains. The N-terminal side of Dpfp1 has 22 tandem repeats of a heptapeptide consensus (P-[V/E]-Y-P-[T/S/delta]-[K/Q]-X); the C-terminal side has 16 repeats of a tridecapeptide motif (K-P-G-P-Y-D-Y-D-G-P-Y-D-K). Both consensus repeats are unique, with some limited homology to other proteins functioning in tension: marine mussel adhesives, plant extensins, titin, and trematode eggshell precursors.
Some results on the upper atmosphere deduced from satellite occultation measurements
Energy Technology Data Exchange (ETDEWEB)
Felske, D.; Knuth, R.; Martini, L.; Ohle, K.H.; Sonnemann, G.; Stark, B.
1980-08-01
Measurements of neutral gas densities in the upper atmosphere deduced from extinction profiles from the Intercosmos 1, 4, 7, 11 and 16 and SOLRAD 9 and 10 solar radiation satellites at sunrise and sunset are presented. Occultation measurements in the Lyman alpha range have revealed the presence of an anomalously high absorption above 110 km in winter, which may be explained by high densities of water in the thermosphere. Calculations of oxygen densities based on extinction profiles measured in Lyman alpha and the Schumann-Runge range also indicate the presence of high densities of NO, and an unknown Lyman alpha absorber of molecular weight corresponding to that of water. Observations obtained for the D-region winter anomaly indicate that the wavelike ionization variations have counterparts in similar neutral thermosphere density variations, which may influence the ion production and/or loss processes. Finally, short-term neutral density fluctuations between 90 and 300 km measured during a strong F-region disturbance are presented which demonstrate sharp rises in O density and decreases in O2 density accompanied by increases in electron concentration during the first phase of the disturbance, the opposite changes during the second phase, and complex mixing variations between O and O2 and their plasma counterparts in the recovery phase.
On the strength of the hydrogen-carbon interaction as deduced from physisorption.
Nguyen, T X; Bae, J-S; Wang, Y; Bhatia, S K
2009-04-21
We deduce a new value for the potential well depth for the C-H2 interaction on the basis of experimental validations of isotherms of H2 and D2 predicted using independently characterized microstructural parameters. We use two carbons, one an activated carbon fiber whose structure has been recently characterized by us (Nguyen, T. X.; cohaut, N.; Bae, J.-S.; Bhatia, S. K. Langmuir 2008, 24, 7912) using hybrid reverse Monte Carlo simulation (HRMC) and the other the commercial Takeda 3A carbon molecular sieve whose pore size distribution is determined here from the 273 K CO2 adsorption isotherm. The conventional grand canonical Monte Carlo simulation technique incorporating a semiclassical Feynman and Hibbs (FH) potential approximation (FHGCMC) as well as path integral Monte Carlo calculations is employed to determine theoretical adsorption isotherms. It is found that curvature enhances the well depth for the LJ C-H2 interaction by a factor of 1.134 over that for a flat graphite surface, consistent with our recent study (Nguyen, T. X.; cohaut, N.; Bae, J.-S.; Bhatia, S. K. Langmuir 2008, 24, 7912). A value of the C-C well depth of 37.26 K, used for estimating the C-H2 well depth in conjunction with the Berthelot rules, with the Steele C-C well depth used for interaction with heavier gases (Ar, CO2 and CH4), leads to excellent agreement with experimental isotherms in all cases.
Shell structure of potassium isotopes deduced from their magnetic moments
Papuga, J; Kreim, K; Barbieri, C; Blaum, K; De Rydt, M; Duguet, T; Garcia Ruiz, R F; Heylen, H; Kowalska, M; Neugart, R; Neyens, G; Nortershauser, W; Rajabali, M M; Sanchez, R; Smirnova, N; Soma, V; Yordanov, D T
2014-01-01
$\\textbf{Background:}$ Ground-state spins and magnetic moments are sensitive to the nuclear wave function, thus they are powerful probes to study the nuclear structure of isotopes far from stability. \\\\ \\\\ $\\textbf{Purpose:}$ Extend our knowledge about the evolution of the $1/2^+$ and $3/2^+$ states for K isotopes beyond the $N = 28$ shell gap. \\\\ \\\\ $\\textbf{Method:}$ High-resolution collinear laser spectroscopy on bunched atomic beams. \\\\ \\\\ $\\textbf{Results:}$ From measured hyperfine structure spectra of K isotopes, nuclear spins and magnetic moments of the ground states were obtained for isotopes from $N = 19$ up to $N = 32$. In order to draw conclusions about the composition of the wave functions and the occupation of the levels, the experimental data were compared to shell-model calculations using SDPF-NR and SDPF-U effective interactions. In addition, a detailed discussion about the evolution of the gap between proton $1d_{3/2}$ and $2s_{1/2}$ in the shell model and $\\textit{ab initio}$ framework is al...
Comet plasma densities deduced from refraction of occulted radio sources
Energy Technology Data Exchange (ETDEWEB)
Wright, C.S. (Commonwealth Department of Science, Ionospheric Prediction Service, Narrabri, New South Wales, Australia); Nelson, G.J. (Commonwealth Scientific and Industrial Research Organization, Div. of Radiophysics, Narrabri, New South Wales, Australia)
1979-04-01
Observations of the occultation of radio sources by comet plasma tails are used to derive the electron density and density gradients in the tails. Occultations of source Culgoora-1 0300+16 by Comet Kohoutek and of Culgoora-1 2313-14 by Comet West were measured by radioheliograph at 80 MHz. After corrections for ionospheric refraction, a 2 arcmin anomaly was observed in the declination of 0300+16, attributed to refraction by the tail of Comet Kohoutek, while none was observed for Comet West. The maximum electron density in the tail of Comet Kohoutek is calculated to be 2 x 10 to the 4th/cu cm, while that of Comet West is 5 x 10 to the 4th/cu cm, with density gradients of about 0.05 per cu cm per km. The direction of refraction observed suggests that the tail of Kohoutek is either highly asymmetric about its axis or has the form of a hollow, cylindrical plasma sheath. The high electron densities observed in Kohoutek may indicate the presence of undetected ion species or a low ionization loss rate.
Energy Technology Data Exchange (ETDEWEB)
Longour, Christophe [Institut de Recherches Subatomiques, B.P.28, 23, Rue du Loess, F-67037 Strasbourg Cedex 2 (France)
1999-04-21
Radioactive decay study gives an access to the interaction which rules the {beta} decay process as well as the structure of the nuclear states involved. This work describes the observation of the decay of N = Z nuclei with mass A > 70. For the odd-odd N = Z nuclei {sup 78}Y, {sup 82}Nb and {sup 86}Tc, the decay has been established as superallowed Fermi type transitions. The results pave the way for more precise measurements and extend the mass range nowadays used to understand the behaviour of the weak interaction in the nuclear matter. The observation of the decay of the even-even N = Z {sup 72}Kr leads us to build the Gamow-Teller strength distribution from which some clues about the ground state deformation of this isotope can be obtained. More complete experimental observation and some developments of the calculations used to interpret the distribution of the Gamow-Teller strength are needed. Finally, this work describes the developments and tests of a prototype detector the aim of which to determine the contribution of {beta} particles to energy distribution observed in germanium detector. The tests we have performed show that this prototype can identify and reject 80% of the {beta} particles emitted by a source with a 2,3 MeV end-point. The very satisfactory performances of this prototype need now to be confirmed under experimental conditions.
Directory of Open Access Journals (Sweden)
L. El Amraoui
2013-07-01
Full Text Available This paper presents a validation of a method to derive the vertical profile of carbon monoxide (CO from its total column using data assimilation. The main motivation of this study is twofold. First, to deduce both the vertical CO profiles and the assimilated CO fields with good confidence. Second, for chemical species that can be measured only as the total column, this method provides an attractive alternative for estimating their vertical profiles in the troposphere. We choose version 3 (V3 of MOPITT CO total columns to validate the proposed method. MOPITT has the advantage of providing both the vertical profiles and the total columns of CO. Furthermore, this version has been extensively validated by comparison with many independent datasets, and has been used in many scientific studies. The first step of the paper consists in the specification of the observation errors based on the Chi-square (χ2 test. The observations have been binned according to day, night, land and sea (LAND_DAY, LAND_NIGHT and SEA, respectively. The respective optimal observation error values for which the χ2 metric is the closest to 1 are: 7%, 8% and 11% for SEA, LAND_DAY and LAND_NIGHT, respectively. In a second step, the CO total column, with its specified errors, is used within the assimilation system to estimate the vertical profiles. These are validated by comparison with vertical profiles of MOPITT V3 retrievals at global and regional scales. Generally, both datasets show similar patterns and good agreement at both global and regional scales. Nevertheless, the total column analyses (TOTCOL_ANALYSES slightly overestimate CO concentrations compared to MOPITT observations. In a third step, vertical profiles calculated from TOTCOL_ANALYSES have been compared to those calculated from the assimilation of MOPITT V3 vertical profiles (PROFILE_ANALYSES. Both datasets shows very good agreement, but TOTCOL_ANALYSES tend to slightly overestimate CO concentrations. The mean
El Amraoui, L.; Attié, J.-L.; Ricaud, P.; Lahoz, W. A.; Piacentini, A.; Peuch, V.-H.; Warner, J. X.; Abida, R.; Barré, J.
2013-07-01
This paper presents a validation of a method to derive the vertical profile of carbon monoxide (CO) from its total column using data assimilation. The main motivation of this study is twofold. First, to deduce both the vertical CO profiles and the assimilated CO fields with good confidence. Second, for chemical species that can be measured only as the total column, this method provides an attractive alternative for estimating their vertical profiles in the troposphere. We choose version 3 (V3) of MOPITT CO total columns to validate the proposed method. MOPITT has the advantage of providing both the vertical profiles and the total columns of CO. Furthermore, this version has been extensively validated by comparison with many independent datasets, and has been used in many scientific studies. The first step of the paper consists in the specification of the observation errors based on the Chi-square (χ2) test. The observations have been binned according to day, night, land and sea (LAND_DAY, LAND_NIGHT and SEA, respectively). The respective optimal observation error values for which the χ2 metric is the closest to 1 are: 7%, 8% and 11% for SEA, LAND_DAY and LAND_NIGHT, respectively. In a second step, the CO total column, with its specified errors, is used within the assimilation system to estimate the vertical profiles. These are validated by comparison with vertical profiles of MOPITT V3 retrievals at global and regional scales. Generally, both datasets show similar patterns and good agreement at both global and regional scales. Nevertheless, the total column analyses (TOTCOL_ANALYSES) slightly overestimate CO concentrations compared to MOPITT observations. In a third step, vertical profiles calculated from TOTCOL_ANALYSES have been compared to those calculated from the assimilation of MOPITT V3 vertical profiles (PROFILE_ANALYSES). Both datasets shows very good agreement, but TOTCOL_ANALYSES tend to slightly overestimate CO concentrations. The mean bias between
Physics-based Inverse Problem to Deduce Marine Atmospheric Boundary Layer Parameters
2017-03-07
please find the Final Technical Report with SF 298 for Dr. Erin E. Hackett’s ONR grant entitled Physics -based Inverse Problem to Deduce Marine...From- To) 07/03/2017 Final Technica l Dec 2012- Dec 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Physics -based Inverse Problem to Deduce Marine...19b. TELEPHONE NUMBER (Include area code) 843-349-4087 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 Physics -Based Inverse Problem To
Rühm, W; Kato, K; Korschinek, G; Morinaga, H; Nolte, E
1995-07-01
In this paper measurements of the radionuclides of 36Cl, 41Ca, 60Co, 152Eu and 154Eu in samples from Hiroshima, which were exposed to neutrons of the A-bomb explosion, are interpreted. In order to calculate the neutron spectrum at the sample site, neutron transport calculations using Monte Carlo techniques were carried out. Activation profiles in a granite mock-up irradiated with reactor neutrons could be reproduced by this method using DS86 input parameters. The calculated neutron spectrum at the sample site for non-thermal neutrons is identical to that obtained in DS86, but contains some 50% more thermal neutrons. The influence of parameters like soil composition, source terms and air humidity on the activation of these radioisotopes is discussed. The granite-covered earth at the sample site, for example, hardens the spectrum in comparison with DS86 values. Even when using a fission spectrum pointing downward and neglecting air humidity one cannot explain our 36Cl measurements. If the effective thermal neutron fluences, that have a similar ratio of resonance integral to thermal neutron capture cross sections obtained from 36Cl, 41Ca and 152Eu, are averaged, a bomb yield of about 16 kt is deduced in agreement with a bomb yield of (15 +/- 3) kt estimated in DS86.
New Route to Deducing Integration Formulas by Virtue of the IWOP Technique*
Institute of Scientific and Technical Information of China (English)
FAN Hong-Yi; LI Hong-Qi; XU Xing-Lei
2011-01-01
We point out a new route to deducing integration formulas, i.e., using the technique of integration within an ordered product (IWOP) of operators we derive some new integration formulas, which seems concise. As a by-product,some new operator identities also appear.
Complete amino acid sequence of human intestinal aminopeptidase N as deduced from cloned cDNA
DEFF Research Database (Denmark)
Cowell, G M; Kønigshøfer, E; Danielsen, E M
1988-01-01
The complete primary structure (967 amino acids) of an intestinal human aminopeptidase N (EC 3.4.11.2) was deduced from the sequence of a cDNA clone. Aminopeptidase N is anchored to the microvillar membrane via an uncleaved signal for membrane insertion. A domain constituting amino acid 250...
CONSISTENT USE OF THE KALMAN FILTER IN CHEMICAL TRANSPORT MODELS (CTMS) FOR DEDUCING EMISSIONS
Past research has shown that emissions can be deduced using observed concentrations of a chemical, a Chemical Transport Model (CTM), and the Kalman filter in an inverse modeling application. An expression was derived for the relationship between the "observable" (i.e., the con...
Wildland fire probabilities estimated from weather model-deduced monthly mean fire danger indices
Haiganoush K. Preisler; Shyh-Chin Chen; Francis Fujioka; John W. Benoit; Anthony L. Westerling
2008-01-01
The National Fire Danger Rating System indices deduced from a regional simulation weather model were used to estimate probabilities and numbers of large fire events on monthly and 1-degree grid scales. The weather model simulations and forecasts are ongoing experimental products from the Experimental Climate Prediction Center at the Scripps Institution of Oceanography...
Energy Technology Data Exchange (ETDEWEB)
Poveda, Ana [Universidad Autonoma de Madrid, Servicio Interdepartamental de Investigacion (Spain); Asensio, Juan Luis; Martin-Pastor, Manuel; Jimenez-Barbero, Jesus [Instituto de Quimica Organica, CSIC, Grupo de Carbohidratos (Spain)
1997-07-15
{sup 1}H-NMR cross-relaxation rates and nonselective longitudinal relaxation times have been obtained at two magnetic fields (7.0 and 11.8 T) and at a variety of temperatures for the branched tetrasaccharide methyl 3-O-{alpha}-N-acetyl-galactosaminyl-{beta}-galactopyranosyl-(1{sup {yields}}4)[3-O-{alpha}-fucosyl] -glucopyranoside (1), an inhibitor of astrocyte growth. In addition, {sup 13}C-NMR relaxation data have also been recorded at both fields. The {sup 1}H-NMR relaxation data have been interpreted using different motional models to obtain proton-proton correlation times. The results indicate that the GalNAc and Fuc rings display more extensive local motion than the two inner Glc and Gal moieties, since those present significantly shorter local correlation times. The{sup 13}C-NMR relaxation parameters have been interpreted in terms of the Lipari-Szabo model-free approach. Thus, order parameters and internal motion correlation times have been deduced. As obtained for the{sup 1}H-NMR relaxation data, the two outer residues possess smaller order parameters than the two inner rings. Internal correlation times are in the order of 100 ps. The hydroxymethyl groups have also different behaviour,with the exocyclic carbon on the glucopyranoside unit showing the highestS{sup 2}. Molecular dynamics simulations using a solvated system have also been performed and internal motion correlation functions have been deduced from these calculations. Order parameters and interproton distances have been compared to those inferred from the NMR measurements. The obtained results are in fair agreement with the experimental data.
SPIN-ISOSPIN EXCITATIONS IN NUCLEI VIA (HE-3,T) REACTIONS AT 450 MEV
FUJIWARA, M; AKIMUNE, H; DAITO, [No Value; EJIRI, H; FUJITA, Y; GREENFIELD, MB; HARAKEH, MN; HAZAMA, R; INOMATA, T; JANECKE, J; KUDOMI, N; KUME, K; NAKAYAMA, S; SHINMYO, K; TAMII, A; TANAKA, M; TOYOKAWA, H; YOSOI, M
1994-01-01
Spin-isospin excitations in nuclei havee been studied by means of the (He-3, t) reactions at 450 MeV. The Gamow-Teller (GT) resonances are found to be strongly excited. A fine structure of the giant Gamow Teller resonances in medium-heavy nuclei is observed with an energy resolution of 130 keV. The
Directory of Open Access Journals (Sweden)
C. M. Hall
Full Text Available By measuring fading times of radar echoes from underdense meteor trails, it is possible to deduce the ambipolar diffusivities of the ions responsible for these radar echoes. It could be anticipated that these diffusivities increase monotonically with height akin to neutral viscosity. In practice, this is not always the case. Here, we investigate the capability of neutral turbulence to affect the meteor trail diffusion rate.
Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; turbulence
Institute of Scientific and Technical Information of China (English)
ZHANG Xiao-Ni; FANG Jian-Hui; PANG Ting; LIN Peng
2009-01-01
For a nonholonomic mechanical system, the generalized Mei conserved quantity and the new generalized Hojman conserved quantity deduced from Noether symmetry of the system are studied.The criterion equation of the Noether symmetry for the system is got.The conditions under which the Noether symmetry can lead to the two new conserved quantities are presented and the forms of the conserved quantities are obtained.Finally, an example is given to illustrate the application of the results.
Hojman conserved quantity deduced by weak Noether symmetry for Lagrange systems
Institute of Scientific and Technical Information of China (English)
Xie Jia-Fang; Gang Tie-Qiang; Mei Feng-Xiang
2008-01-01
This paper studies the Hojman conserved quantity,a non-Noether conserved quantity,deduced by special weak Noether symmetry for Lagrange systems.Under special infinitesimal transformations in which the time is not variable,its criterion is given and a method of how to seek the Hojman conserved quantity is presented.A Hojman conserved quantity can be found by using the special weak Noether symmetry.
Fungal diversity from various marine habitats deduced through culture-independent studies
Digital Repository Service at National Institute of Oceanography (India)
Manohar, C.S.; Raghukumar, C.
Author version: FEMS Microbiol. Lett., vol.341; 2013; 69-78 Fungal diversity from various marine habitats deduced through culture-independent studies Cathrine Sumathi Manohar* and Chandralata Raghukumar$ National Institute of Oceanography, (Council...: un-cultured fungal diversity from marine habitats Abstract Studies on the molecular diversity of the micro-eukaryotic community have shown that fungi occupy a central position in a large number of marine habitats. Environmental surveys using...
National Oceanic and Atmospheric Administration, Department of Commerce — Declination is calculated using the current International Geomagnetic Reference Field (IGRF) model. Declination is calculated using the current World Magnetic Model...
曲率圆弧段代替切线段的数值计算方法%A NOVEL NUMERICAL CALCULATION METHOD
Institute of Scientific and Technical Information of China (English)
蔡章生; 蔡琦
2002-01-01
In this paper, A novel numerical calculation method is deduced. Comparing with LongGe-Kuta method, it is better to satisfy the engineer calculation demand which is that the calculation value should be larger than the real value.
Thick-target yields of radioactive targets deduced from inverse kinematics
Energy Technology Data Exchange (ETDEWEB)
Aikawa, M., E-mail: aikawa@sci.hokudai.ac.jp [Faculty of Science, Hokkaido University, Sapporo 060-0810 (Japan); Ebata, S.; Imai, S. [Meme Media Laboratory, Hokkaido University, Sapporo 060-8628 (Japan)
2015-06-15
The thick-target yield (TTY) is a macroscopic quantity reflected by nuclear reactions and matter properties of targets. In order to evaluate TTYs on radioactive targets, we suggest a conversion method from inverse kinematics corresponding to the reaction of radioactive beams on stable targets. The method to deduce the TTY is theoretically derived from inverse kinematics. We apply the method to the {sup nat}Cu({sup 12}C,X){sup 24}Na reaction to confirm availability. In addition, it is applied to the {sup 137}Cs + {sup 12}C reaction as an example of a radioactive system and discussed a conversion coefficient of a TTY measurement.
Rabbit serum amyloid protein A: expression and primary structure deduced from cDNA sequences.
Rygg, M; Marhaug, G; Husby, G; Dowton, S B
1991-12-01
Serum amyloid A protein (SAA), the precursor of amyloid protein A (AA) in deposits of secondary amyloidosis, is an acute phase plasma apolipoprotein produced by hepatocytes. The primary structure of SAA demonstrates high interspecies homology. Several isoforms exist in individual species, probably with different amyloidogenic potential. The nucleotide sequences of two different rabbit serum amyloid A cDNA clones have been analysed, one (corresponding to SAA1) 569 base pairs (bp) long and the other (corresponding to SAA2) 513 bp long. Their deduced amino acid sequences differ at five amino acid positions, four of which are located in the NH2-terminal region of the protein. The deduced amino acid sequence of SAA2 corresponds to rabbit protein AA previously described except for one amino acid in position 22. Eighteen hours after turpentine stimulation, rabbit SAA mRNA is abundant in liver, while lower levels are present in spleen. None of the other extrahepatic organs studied showed any SAA mRNA expression. A third mRNA species (1.9 kb) hybridizing with a single-stranded RNA probe transcribed from the rabbit SAA cDNA, was identified. SAA1 and SAA2 mRNA were found in approximately equal amounts in turpentine-stimulated rabbit liver, but seem to be coordinately decreased after repeated inflammatory stimulation.
A Calculation Model for Corrosion Cracking in RC Structures
Institute of Scientific and Technical Information of China (English)
Xu Gang; Wei Jun; Zhang Keqiang; Zhou Xiwu
2007-01-01
A novel calculation model is proposed aiming at the problem of concrete cover cracking induced by reinforcement corrosion. In this article, the relationship between the corrosion depth of the bar and the thickness of the rust layer is established. By deducing the radial displacement expression of concrete, the formula for corrosion depth and corrosion pressure before cracking is proposed. The crack depth of cover in accordance with the maximum corrosion pressure is deduced; furthermore, the corrosion depth and corrosion pressure at the cracking time are obtained. Finally, the theoretical model is validated by several experiments, and the calculated values agree well with the experiment results.
Dzhioev, Alan A.; Vdovin, A. I.; Martínez-Pinedo, G.; Wambach, J.; Stoyanov, Ch.
2016-07-01
The thermal quasiparticle random-phase approximation is combined with the Skyrme energy density functional method (Skyrme-TQRPA) to study the response of a hot nucleus to an external perturbation. For the sample nuclei 56Fe and 82Ge, the Skyrme-TQRPA is applied to analyze thermal effects on the strength function of charge-neutral Gamow-Teller transitions, which dominate neutrino-nucleus reactions at Eν≲20 MeV. For the relevant supernova temperatures we calculate the cross sections for inelastic neutrino scattering. We also apply the method to examine the rate of neutrino-antineutrino pair emission by hot nuclei. The cross sections and rates are compared with those obtained earlier from the TQRPA calculations based on the phenomenological quasiparticle-phonon model Hamiltonian. For inelastic neutrino scattering on 56Fe we also compare the Skyrme-TQRPA results to those obtained earlier from a hybrid approach that combines shell-model and RPA calculations.
Neutrino absorption by hot nuclei in supernova environments
Dzhioev, Alan A; Wambach, J
2015-01-01
Using the thermal quasiparticle random phase approximation, we study the process of neutrino and antineutrino capture on hot nuclei in supernova environments. For the sample nuclei $^{56}$Fe and $^{82}$Ge we perform a detailed analysis of thermal effects on the strength distribution of allowed Gamow-Teller transitions which dominate low-energy charged-current neutrino reactions. The finite temperature cross sections are calculated taking into account the contributions of both allowed and forbidden transitions. The enhancement of the low-energy cross sections is explained by considering thermal effects on the GT$_\\pm$ strength. For $^{56}$Fe we compare the calculated finite-temperature cross sections with those obtained from large-scale shell-model calculations.
Neutrino absorption by hot nuclei in supernova environments
Dzhioev, Alan A.; Vdovin, A. I.; Wambach, J.
2015-10-01
Using the thermal quasiparticle random-phase approximation, we study the process of neutrino and antineutrino capture on hot nuclei in supernova environments. For the sample nuclei 56Fe and 82Ge we perform a detailed analysis of thermal effects on the strength distribution of allowed Gamow-Teller (GT) transitions which dominate low-energy charged-current neutrino reactions. The finite-temperature cross sections are calculated taking into account the contributions of both allowed and forbidden transitions. The enhancement of the low-energy cross sections is explained by considering thermal effects on the GT± strength. For 56Fe we compare the calculated finite-temperature cross sections with those obtained from large-scale shell-model calculations.
Beta decay and muon capture rates in a self-consistent relativistic framework
Energy Technology Data Exchange (ETDEWEB)
Marketin, Tomislav; Paar, Nils; Niksic, Tamara; Vretenar, Dario [Physics Department, Faculty of Science, University of Zagreb (Croatia); Ring, Peter [Physik-Department, Technische Universitaet Muenchen, D-85748 Muenchen (Germany)
2009-07-01
A fully consistent calculation of muon capture and beta decay rates is presented, based on a microscopic theoretical framework describing the semileptonic weak interaction processes. Nuclear ground state is determined using the Relativistic Hartree-Bogolyubov (RHB) model with density dependent meson-nucleon coupling constants, and transition rates are calculated via proton-neutron relativistic quasiparticle RPA using the same interaction as in the RHB equations. Muon capture rates are calculated for a wide range of nuclei along the valley of stability, from {sup 12}C to {sup 244}Pu, with accuracy of approximately 30%, using the interaction DD-ME2. Previous studies of beta decay rates have only taken into account Gamow-Teller transitions. We extend this approach by including forbidden transitions and systematically study their contribution to decay rates of exotic nuclei along the r-process path, which are important for constraining the conditions in which nucleosynthesis takes place.
Tritium $\\beta$-decay in pionless effective field theory
De-Leon, Hilla; Gazit, Doron
2016-01-01
We calculate the $\\beta$-decay of tritium, i.e., of its $^3$H nucleus (triton), at next-to-leading order in pionless effective field theory. At this order a low-energy parameter $L_{1A}$ enters the calculation that is also relevant for a high-accuracy prediction of the solar proton-proton fusion rate. We show proper renormalization of our perturbative calculation by an analysis of the residual cutoff dependence in observables. We find that next-to-leading order corrections contribute about $1\\%$ to the triton decay Gamow-Teller strength. We show that these conclusions are insensitive to different arrangements of the effective range expansion. We use these to fix $L_{1A}$ to high accuracy, and provide reliable theoretical and experimental uncertainty estimates.
Neutrino-nucleus reactions and their role for supernova dynamics and nucleosynthesis
Balasi, K G; Martínez-Pinedo, G
2015-01-01
The description of nuclear reactions induced by supernova neutrinos has witnessed significant progress during the recent years. At the energies and momentum transfers relevant for supernova neutrinos neutrino-nucleus cross sections are dominated by allowed transitions, however, often with non-negligible contributions from (first) forbidden transitions. For several nuclei allowed Gamow-Teller strength distributions could be derived from charge-exchange reactions and from inelastic electron scattering data. Importantly the diagonalization shell model has been proven to accurately describe these data and hence became the appropriate tool to calculate the allowed contributions to neutrino-nucleus cross sections for supernova neutrinos. Higher multipole contributions are usually calculated within the framework of the Quasiparticle Random Phase Approximation, which describes the total strength and the position of the giant resonances quite well. This manuscript reviews the recent progress achieved in calculating su...
Deducing the Kinetics of Protein Synthesis In Vivo from the Transition Rates Measured In Vitro
Rudorf, Sophia; Thommen, Michael; Rodnina, Marina V.; Lipowsky, Reinhard
2014-01-01
The molecular machinery of life relies on complex multistep processes that involve numerous individual transitions, such as molecular association and dissociation steps, chemical reactions, and mechanical movements. The corresponding transition rates can be typically measured in vitro but not in vivo. Here, we develop a general method to deduce the in-vivo rates from their in-vitro values. The method has two basic components. First, we introduce the kinetic distance, a new concept by which we can quantitatively compare the kinetics of a multistep process in different environments. The kinetic distance depends logarithmically on the transition rates and can be interpreted in terms of the underlying free energy barriers. Second, we minimize the kinetic distance between the in-vitro and the in-vivo process, imposing the constraint that the deduced rates reproduce a known global property such as the overall in-vivo speed. In order to demonstrate the predictive power of our method, we apply it to protein synthesis by ribosomes, a key process of gene expression. We describe the latter process by a codon-specific Markov model with three reaction pathways, corresponding to the initial binding of cognate, near-cognate, and non-cognate tRNA, for which we determine all individual transition rates in vitro. We then predict the in-vivo rates by the constrained minimization procedure and validate these rates by three independent sets of in-vivo data, obtained for codon-dependent translation speeds, codon-specific translation dynamics, and missense error frequencies. In all cases, we find good agreement between theory and experiment without adjusting any fit parameter. The deduced in-vivo rates lead to smaller error frequencies than the known in-vitro rates, primarily by an improved initial selection of tRNA. The method introduced here is relatively simple from a computational point of view and can be applied to any biomolecular process, for which we have detailed information
Deducing the kinetics of protein synthesis in vivo from the transition rates measured in vitro.
Directory of Open Access Journals (Sweden)
Sophia Rudorf
2014-10-01
Full Text Available The molecular machinery of life relies on complex multistep processes that involve numerous individual transitions, such as molecular association and dissociation steps, chemical reactions, and mechanical movements. The corresponding transition rates can be typically measured in vitro but not in vivo. Here, we develop a general method to deduce the in-vivo rates from their in-vitro values. The method has two basic components. First, we introduce the kinetic distance, a new concept by which we can quantitatively compare the kinetics of a multistep process in different environments. The kinetic distance depends logarithmically on the transition rates and can be interpreted in terms of the underlying free energy barriers. Second, we minimize the kinetic distance between the in-vitro and the in-vivo process, imposing the constraint that the deduced rates reproduce a known global property such as the overall in-vivo speed. In order to demonstrate the predictive power of our method, we apply it to protein synthesis by ribosomes, a key process of gene expression. We describe the latter process by a codon-specific Markov model with three reaction pathways, corresponding to the initial binding of cognate, near-cognate, and non-cognate tRNA, for which we determine all individual transition rates in vitro. We then predict the in-vivo rates by the constrained minimization procedure and validate these rates by three independent sets of in-vivo data, obtained for codon-dependent translation speeds, codon-specific translation dynamics, and missense error frequencies. In all cases, we find good agreement between theory and experiment without adjusting any fit parameter. The deduced in-vivo rates lead to smaller error frequencies than the known in-vitro rates, primarily by an improved initial selection of tRNA. The method introduced here is relatively simple from a computational point of view and can be applied to any biomolecular process, for which we have
Ivanov, Yurii P.
2014-02-14
The magneto-optic Kerr effect has been employed to determine the magnetization process and estimate the domain structure of microwires with circular magnetic anisotropy. The diameter of microwires was 8 μm, and pieces 2 cm long were selected for measurements. The analysis of the local surface longitudinal and transverse hysteresis loops has allowed us to deduce a vortex magnetic structure with axial core and circular external shell. Moreover, a bamboo-like surface domain structure is confirmed with wave length of around 10 to 15 μm and alternating chirality in adjacent circular domains. The width of the domain wall is estimated to be less than 3 μm. Finally, closure domain structures with significant helical magnetization component are observed extending up to around 1000 μm from the end of the microwire.
Oxygen plasma flow properties deduced from laser-induced fluorescence and probe measurements
Löhle, Stefan; Eichhorn, Christoph; Steinbeck, Andreas; Lein, Sebastian; Herdrich, Georg; Röser, Hans-Peter; Auweter-Kurtz, Monika
2008-04-01
Estimation of the local dissociation degree and the local mass-specific enthalpy of a pure oxygen plasma flow determined mainly from laser-induced fluorescence measurements are reported. Measurements have been conducted for several generator parameters in an inductively heated plasma wind tunnel. Additional probe measurements of total pressure together with the deduced translational temperature are used to estimate the local mass-specific enthalpy. For a reference condition, full dissociation has been measured. The measured translational temperature of atomic oxygen for this condition is T = 3500 K. Subsequently, the local mass-specific enthalpy has been derived using these local density and temperature measurements. For the reference condition the estimated value of h = 27 MJ/kg is in good agreement with the probe measurements and results from diode laser absorption spectroscopy.
Thick-target yields of radioactive targets deduced from inverse kinematics
Aikawa, Masayuki; Imai, Shotaro
2014-01-01
The thick-target yield (TTY) of long-lived fission products (LLFP) is an essential quantity and represents basic data for transmutation. In order to evaluate TTY on radioactive targets including LLFP, we suggest a conversion method from inverse kinematics corresponding to the reaction of radioactive beams on stable targets. We demonstrate the method to deduce the TTY from inverse kinematics derived from the theoretical definition. This method is highly applicable in reactions at the energy per nucleon \\epsilon > 20 MeV/A as practically confirmed by the simulation of the SRIM2008 code. In this paper, we apply the method to the natCu(12C,X)24Na reaction to confirm availability. In addition, it is applied to the 137Cs + 12C reaction to reduce 137Cs and to suggest a TTY measurement of the 137Cs induced reaction on a thick 12C target.
Indian Academy of Sciences (India)
C J Johny; S K Sarkar; D Punyasesudu
2009-02-01
The tropopause height and tropopause temperature are sensitive to temperature changes in troposphere and stratosphere. These are the measures of global climatic variability. Atmospheric profiles of temperature, refractivity and water vapour are always needed for communication, navigation and atmospheric modeling studies. The tropopause characteristics over the Indian region have been studied using radio occultation measurements (CHAMP) on the basis of cold point criterion. Tropopause height shows large variation in the latitude range ∼30° –40°N during winter. Tropopause temperature less than −82°C, assumed to facilitate troposphere to stratosphere air transport, is observed at a number of tropical Indian locations and no seasonal pattern is observed in its occurrence. The bias in temperature and refractivity deduced from radiosonde and radio occultation measurements is also presented.
An asymmetric color image encryption method by using deduced gyrator transform
Yao, Lili; Yuan, Caojin; Qiang, Junjie; Feng, Shaotong; Nie, Shouping
2017-02-01
An encryption algorithm is proposed by using the properties of deduced gyrator transform (GT). After being transformed by the GT algorithm and multiplied by a phase distribution p*, the spectrum modulus of the input image is considered to be the encrypted image by further performing Fourier transformation. To resist the attack from iterative phase retrieval, the red, green and blue components of the input image is modulated by a random phase mask and then combined using convolution. The encryption result is real-valued, which is convenient for display, transmission and storage. In the decryption process, the three original color components can be recovered with decryption keys which are different from the encryption keys. An optoelectronic hybrid system for the encryption process is also presented. Computer simulations are presented to demonstrate its performance, and the security of the proposed system is analyzed as well.
Martian low-altitude magnetic topology deduced from MAVEN/SWEA observations
Xu, Shaosui; Mitchell, David; Liemohn, Michael; Fang, Xiaohua; Ma, Yingjuan; Luhmann, Janet; Brain, David; Steckiewicz, Morgane; Mazelle, Christian; Connerney, Jack; Jacosky, Bruce
2016-10-01
The Mars Atmosphere and Volatile Evolution (MAVEN) mission for the first time make regular particle and field measurements down to ~150 km altitude. The Solar Wind Electron Analyzer (SWEA) instrument provides 3-D measurements of the electron energy and angular distributions. This study presents the pitch angle-resolved shape parameters that can separate photoelectrons from solar wind electrons, therefore used to deduce the Martian magnetic topology. The three-dimensional view of the magnetic topology is manifested for the first time. The northern hemisphere is found to be dominated by the crustal closed field lines, instead of draped interplanetary magnetic fields (IMF), on the dayside and more day-night connections through cross-terminator closed field lines than in the south. This study can also single out open field lines attached to the dayside ionosphere, which provide possible passage for ion outflow. Magnetic topology governs energetic electrons' movement, thus necessary to understand nightside ionosphere, and aurora.
Hydrodynamic properties of gamma-ray bursts outflows deduced from thermal component
Pe'er, Asaf; O'Mahony, Shane; Margutti, Raffaella; Ryde, Felix; Larsson, Josefin; Lazzatti, Davide; Livio, Mario
2015-01-01
We study the properties of a significant thermal emission component that was identified in 47 GRBs observed by different instruments. Within the framework of the "fireball" model, we deduce the values of the Lorentz factor Gamma, and the acceleration radius, r_0, for these bursts. We find that all the values of Gamma in our sample are in the range 10^2 = 310. We find a very weak dependence of Gamma on the acceleration radius r_0, Gamma ~ r_0^alpha with alpha = -0.10 +- 0.09 at sigma = 2.1 confidence level. The values of r_0 span a wide range, 10^7 ~10^{8.5} cm. This is higher than the gravitational radius of a 10 M_sun black hole by a factor ~100. We argue that this result provides indirect evidence for jet propagation inside a massive star, and suggests the existence of recollimation shocks that take place close to this radius.
New values of gravitational moments J2 and J4 deduced from helioseismology
Redouane, Mecheri; Irbah, Abdanour; Provost, Janine; Berthomieu, Gabrielle; 10.1023/B:SOLA.0000043563.96766.21
2009-01-01
By applying the theory of slowly rotating stars to the Sun, the solar quadrupole and octopole moments J2 and J4 were computed using a solar model obtained from CESAM stellar evolution code (Morel, 1997) combined with a recent model of solar differential rotation deduced from helioseismology (Corbard et al., 2002). This model takes into account a near-surface radial gradient of rotation which was inferred and quantified from MDI f-mode observations by Corbard and Thompson (2002). The effect of this observational near-surface gradient on the theoretical values of the surface parameters J2, J4 is investigated. The results show that the octopole moment J4 is much more sensitive than the quadrupole moment J2 to the subsurface radial gradient of rotation.
Transition Strength Sums and Quantum Chaos in Shell Model States
Kota, V K B; Kar, K; Gómez, J M G; Retamosa, J
2000-01-01
For the embedded Gaussian orthogonal ensemble (EGOE) of random matrices, the strength sums generated by a transition operator acting on an eigenstate vary with the excitation energy as the ratio of two Gaussians. This general result is compared to exact shell model calculations, with realistic interactions, of spherical orbit occupancies and Gamow-Teller strength sums in some $(ds)$ and $(fp)$ shell examples. In order to confirm that EGOE operates in the chaotic domain of the shell model spectrum, calculations are carried out using two different interpolating hamiltonians generating order-chaos transitions. Good agreement is obtained in the chaotic domain of the spectrum, and strong deviations are observed as nuclear motion approaches a regular regime (transition strength sums appear to follow the Dyson's $\\Delta_3$ statistic). More importantly, they shed new light on the newly emerging understanding that in the chaotic domain of isolated finite interacting many particle systems smoothed densities (they inclu...
Supernova neutrino scattering on the 56Fe nucleus at infinite temperatures
Dzhioev, Alan A.; Vdovin, A. I.; Tsakstara, V.; Kosmas, T. S.
2013-02-01
Thermal effects on the neutral-current inelastic neutrino-nucleus scattering in a supernova environment are examined by using the thermal quasi-particle random phase approximation (TQRPA). We concentrate on the total cross section of neutrino scattering on the nucleus 56Fe, which plays a significant role in core collapse supernova dynamics. The calculations are performed for several nuclear temperatures relevant for supernova physics and for incoming neutrino energies up to 60 MeV. Our results show that finite temperature effects cause a significant enhancement in the cross section for low-energy neutrinos. These findings are in agreement with previous large-scale shell-model calculations where such an increase is closely related to Gamow-Teller transitions stemming from thermally populated nuclear states.
Inelastic neutrino scattering off hot nuclei in supernova environments
Dzhioev, Alan A; Wambach, J; Ponomarev, V Yu
2014-01-01
We study inelastic neutrino scattering off hot nuclei for temperatures relevant under supernova conditions. The method we use is based on the quasiparticle random phase approximation extended to finite temperatures within the thermo field dynamics (TQRPA). The method allows a transparent treatment of upward and downward transitions in hot nuclei, avoiding the application of Brink's hypothesis. For the sample nuclei $^{56}$Fe and $^{82}$Ge we perform a detailed analysis of thermal effects on the strength distributions of allowed Gamow-Teller (GT) transitions which dominate the scattering process at low neutrino energies. For $^{56}$Fe and $^{82}$Ge the finite temperature cross-sections are calculated by taking into account the contribution of allowed and forbidden transitions. The observed enhancement of the cross-section at low neutrino energies is explained by considering thermal effects on the GT strength. For $^{56}$Fe we compare the calculated cross-sections to those obtained earlier from a hybrid approac...
Shell-model half-lives for r-process waiting point nuclei including first-forbidden contributions
Zhi, Q; Cuenca-García, J J; Langanke, K; Martínez-Pinedo, G; Sieja, K
2013-01-01
We have performed large-scale shell-model calculations of the half-lives and neutron-branching probabilities of the r-process waiting point nuclei at the magic neutron numbers N=50, 82, and 126. The calculations include contributions from allowed Gamow-Teller and first-forbidden transitions. We find good agreement with the measured half-lives for the N=50 nuclei with charge numbers Z=28-32 and for the N=82 nuclei 129Ag and 130Cd. The contribution of forbidden transitions reduce the half-lives of the N=126 waiting point nuclei significantly, while they have only a small effect on the half-lives of the N=50 and 82 r-process nuclei.
Crespo Campo, L.; Bello Garrote, F. L.; Eriksen, T. K.; Görgen, A.; Guttormsen, M.; Hadynska-Klek, K.; Klintefjord, M.; Larsen, A. C.; Renstrøm, T.; Sahin, E.; Siem, S.; Springer, A.; Tornyi, T. G.; Tveten, G. M.
2016-10-01
Particle-γ coincidence data have been analyzed to obtain the nuclear level density and the γ -strength function of 64Ni by means of the Oslo method. The level density found in this work is in very good agreement with known energy levels at low excitation energies as well as with data deduced from particle-evaporation measurements at excitation energies above Ex≈5.5 MeV. The experimental γ -strength function presents an enhancement at γ energies below Eγ≈3 MeV and possibly a resonancelike structure centered at Eγ≈9.2 MeV. The obtained nuclear level density and γ -strength function have been used to estimate the (n ,γ ) cross section for the s -process branch-point nucleus 63Ni, of particular interest for astrophysical calculations of elemental abundances.
Shell Model description of the {beta}{beta} decay of {sup 136}Xe
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Caurier, E.; Nowacki, F. [IPHC, IN2P3-CNRS/Universite Louis Pasteur BP 28, F-67037 Strasbourg Cedex 2 (France); Poves, A., E-mail: alfredo.poves@uam.es [Departamento de Fisica Teorica, Universidad Autonoma de Madrid and Instituto de Fisica Teorica, UAM/CSIC, E-28049, Madrid (Spain)
2012-05-01
We study in this Letter the double beta decay of {sup 136}Xe with emission of two neutrinos which has been recently measured by the EXO-200 Collaboration. We use the same shell model framework, valence space, and effective interaction that we have already employed in our calculation of the nuclear matrix element (NME) of its neutrinoless double beta decay. Using the quenching factor of the Gamow-Teller operator which is needed to reproduce the very recent high resolution {sup 136}Xe ({sup 3}He, t) {sup 136}Cs data, we obtain a nuclear matrix element M{sup 2{nu}}=0.025 MeV{sup -1} compared with the experimental value M{sup 2{nu}}=0.019(2) MeV{sup -1}.
Gogny interactions with tensor terms
Energy Technology Data Exchange (ETDEWEB)
Anguiano, M.; Lallena, A.M.; Bernard, R.N. [Universidad de Granada, Departamento de Fisica Atomica, Molecular y Nuclear, Granada (Spain); Co' , G. [INFN, Lecce (Italy); De Donno, V. [Universita del Salento, Dipartimento di Matematica e Fisica ' ' E. De Giorgi' ' , Lecce (Italy); Grasso, M. [Universite Paris-Sud, Institut de Physique Nucleaire, IN2P3-CNRS, Orsay (France)
2016-07-15
We present a perturbative approach to include tensor terms in the Gogny interaction. We do not change the values of the usual parameterisations, with the only exception of the spin-orbit term, and we add tensor terms whose only free parameters are the strengths of the interactions. We identify observables sensitive to the presence of the tensor force in Hartree-Fock, Hartree-Fock-Bogoliubov and random phase approximation calculations. We show the need of including two tensor contributions, at least: a pure tensor term and a tensor-isospin term. We show results relevant for the inclusion of the tensor term for single-particle energies, charge-conserving magnetic excitations and Gamow-Teller excitations. (orig.)
On the extraction of weak transition strengths via the (3He,t) reaction at 420 MeV
Zegers, R G T; Akimune, H; Austin, Sam M; Berg, A M van den; Brown, B A; Fujita, Y; Fujiwara, M; Galès, S; Guess, C J; Harakeh, M N; Hashimoto, H; Hatanaka, K; Hayami, R; Hitt, G W; Howard, M E; Itoh, M; Kawabata, T; Kawase, K; Kinoshita, M; Matsubara, M; Nakanishi, K; Nakayama, S; Okumura, S; Ohta, T; Sakemi, Y; Shimbara, Y; Shimizu, Y; Scholl, C; Simenel, C; Tameshige, Y; Tamii, A; Uchida, M; Yamagata, T; Yosoi, M
2007-01-01
Differential cross sections for transitions of known weak strength were measured with the (3He,t) reaction at 420 MeV on targets of 12C, 13C, 18O, 26Mg, 58Ni, 60Ni, 90Zr, 118Sn, 120Sn and 208Pb. Using this data, it is shown the proportionalities between strengths and cross sections for this probe follow simple trends as a function of mass number. These trends can be used to confidently determine Gamow-Teller strength distributions in nuclei for which the proportionality cannot be calibrated via beta-decay strengths. Although theoretical calculations in distorted-wave Born approximation overestimate the data, they allow one to understand the main experimental features and to predict deviations from the simple trends observed in some of the transitions.
Modification of the Brink-Axel Hypothesis for High Temperature Nuclear Weak Interactions
Misch, G Wendell; Brown, B Alex
2014-01-01
We present shell model calculations of electron capture strength distributions in A=28 nuclei and computations of the corresponding capture rates in supernova core conditions. We find that in these nuclei the Brink-Axel hypothesis for the distribution of Gamow-Teller strength fails at low and moderate initial excitation energy, but may be a valid tool at high excitation. The redistribution of GT strength at high initial excitation may affect capture rates during collapse. If these trends which we have found in lighter nuclei also apply for the heavier nuclei which provide the principal channels for neutronization during stellar collapse, then there could be two implications for supernova core electron capture physics. First, a modified Brink-Axel hypothesis could be a valid approximation for use in collapse codes. Second, the electron capture strength may be moved down significantly in transition energy, which would likely have the effect of increasing the overall electron capture rate during stellar collapse...
Energy Technology Data Exchange (ETDEWEB)
Paar, N. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); University of Zagreb, Physics Department, Faculty of Science (Croatia); University of Washington, Institute for Nuclear Theory, Seattle (United States); Niksic, T. [University of Zagreb, Physics Department, Faculty of Science (Croatia); University of Washington, Institute for Nuclear Theory, Seattle (United States); Marketin, T.; Vretenar, D. [University of Zagreb, Physics Department, Faculty of Science (Croatia); Ring, P. [Physik-Department der Technischen Universitaet Muenchen, Garching (Germany)
2005-09-01
The excitation phenomena in unstable nuclei are investigated in the framework of the relativistic quasiparticle random-phase approximation (RQRPA) in the relativistic Hartree-Bogolyubov model (RHB) which is extended to include effective interactions with explicit density-dependent meson-nucleon couplings. The properties of the pygmy dipole resonance (PDR) are examined in {sup 132}Sn and within isotopic chains, showing that already at moderate proton-neutron asymmetry the PDR peak energy is located above the neutron emission threshold. A method is suggested for determining the size of the neutron skin within an isotopic chain, based on the measurement of the excitation energies of the Gamow-Teller resonance relative to the isobaric analog state. In addition, for the first time the relativistic RHB+RQRPA model, with tensor {omega} meson-nucleon couplings, is employed in calculations of {beta}-decay half-lives of nuclei of the relevance for the r-process. (orig.)
Uncertainties in modeling low-energy neutrino induced reactions on iron group nuclei
Paar, N; Honma, M; Marketin, T; Vretenar, D
2011-01-01
Charged-current neutrino-nucleus cross sections for 54,56Fe and 58,60Ni are calculated and compared using frameworks based on relativistic and Skyrme energy density functionals, and the shell model. The current theoretical uncertainties in modeling neutrino-nucleus cross sections are assessed in relation to the predicted Gamow-Teller transition strength and available data, multipole decomposition of the cross sections, and cross sections averaged over the Michel flux and Fermi-Dirac distribution. Employing different microscopic approaches and models, the DAR neutrino-56Fe cross section and its theoretical uncertainty are estimated: _th=(258+-57) 10^{-42} cm^2, in very good agreement with the experimental value: _exp=(256+-108+-43) 10^{-42} cm^2.
Beta-decay in odd-A and even-even proton-rich Kr isotopes
Sarriguren, P; Escuderos, A
2001-01-01
Beta-decay properties of proton-rich odd-A and even-even Krypton isotopes are studied in the framework of a deformed selfconsistent Hartree-Fock calculation with density-dependent Skyrme forces, including pairing correlations between like nucleons in BCS approximation. Residual spin-isospin interactions are consistently included in the particle-hole and particle-particle channels and treated in Quasiparticle Random Phase Approximation. The similarities and differences in the treatment of even-even and odd-A nuclei are stressed. Comparison to available experimental information is done for Gamow-Teller strength distributions, summed strengths, and half-lives. The dependence of these observables on deformation is particularly emphasized in a search for signatures of the shape of the parent nucleus.
De Witte, H; Borzov, I N; Caurier, E; Cederkäll, J; De Smet, A; Eckhaudt, S; Fedorov, D V; Fedosseev, V; Franchoo, S; Górska, M; Grawe, H; Huber, G; Huyse, M; Janas, Z; Köster, U; Kurcewicz, W; Kurpeta, J; Plochocki, A; Van Duppen, P; Van de Vel, K; Weissman, L
2004-01-01
The neutron-rich isotope /sup 218/Bi has been produced in proton- induced spallation of a uranium carbide target at the ISOLDE facility at CERN, extracted from the ion source by the pulsed-release technique and resonant laser ionization, and its beta decay is studied for the first time. A half-life of 33(1)s was measured and is discussed in the self-consistent continuum-quasi particle-random- phase approximation framework that includes Gamow-Teller and first- forbidden transitions. A level scheme was constructed for /sup 218 /Po, and a deexcitation pattern of stretched E2 transitions 8/sup +/ to 6/sup +/ to 4/sup +/ to 2/sup +/ to 0/sup +/ to the ground state is suggested. Shell-model calculations based on the Kuo-Herling interaction reproduce the experimental results satisfactorily. (28 refs).
Beta-decay properties of neutron-rich medium-mass nuclei
Sarriguren, Pedro
2016-06-01
β-decay properties of even-even and odd-A neutron-rich Ge, Se, Kr, Sr, Zr, Mo, Ru, and Pd isotopes involved in the astrophysical rapid neutron capture process are studied within a microscopic proton-neutron quasiparticle random-phase approximation. The underlying mean field is based on a self-consistent Skyrme Hartree-Fock + BCS calculation that includes deformation as a key ingredient. The isotopic evolution of the various nuclear equilibrium shapes and the corresponding charge radii are investigated in all the isotopic chains. The energy distributions of the Gamow-Teller strength, as well as the β-decay half-lives are discussed and compared with the available experimental information. It is shown that nuclear deformation plays a significant role in the description of the decay properties in this mass region. Reliable predictions of the strength distributions are essential to evaluate decay rates in astrophysical scenarios.
Neutron-gamma competition for $\\beta$-delayed neutron emission
Mumpower, Matthew; Moller, Peter
2016-01-01
We present a coupled Quasi-particle Random Phase Approximation and Hauser-Feshbach (QRPA+HF) model for calculating delayed particle emission. This approach uses microscopic nuclear structure information which starts with Gamow-Teller strength distributions in the daughter nucleus, and then follows the statistical decay until the initial available excitation energy is exhausted. Explicitly included at each particle emission stage is $\\gamma$-ray competition. We explore this model in the context of neutron emission of neutron-rich nuclei and find that neutron-gamma competition can lead to both increases and decreases in neutron emission probabilities, depending on the system considered. A second consequence of this formalism is a prediction of more neutrons on average being emitted after $\\beta$-decay for nuclei near the neutron dripline compared to models that do not consider the statistical decay.
β-decay properties of neutron-deficient Pt, Hg, and Pb isotopes
Energy Technology Data Exchange (ETDEWEB)
Sarriguren, P., E-mail: p.sarriguren@csic.es [Instituto de Estructura de la Materia, IEM-CSIC, Serrano 123, E-28006 Madrid (Spain); Boillos, J. M. [Instituto de Estructura de la Materia, IEM-CSIC, Serrano 123, E-28006 Madrid (Spain); Universidad de Santiago de Compostela, 15706 Santiago de Compostela (Spain); Moreno, O. [Center for Theoretical Physics, Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Moya de Guerra, E. [Departamento de Física Atómica, Molecular y Nuclear, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain)
2015-10-15
Neutron-deficient isotopes in the lead region are well established examples of the shape coexistence phenomenon in nuclei. In this work, bulk and decay properties, including deformation energy curves, charge mean square radii, Gamow-Teller (GT) strength distributions, and β-decay half-lives, are studied in neutron-deficient Pt, Hg, and Pb isotopes. The nuclear structure involved is described microscopically from deformed quasiparticle random-phase approximation calculations with residual interactions in both particle-hole and particle-particle channels, performed on top of a self-consistent deformed quasiparticle Skyrme Hartree-Fock basis. The sensitivity to deformation of the GT strength distributions in those isotopes is proposed as an additional complementary signature of the nuclear shape. The β-decay half-lives resulting from the GT strength distributions are compared to experiment to demonstrate the ability of the method.
Proton-Proton Fusion and Tritium β Decay from Lattice Quantum Chromodynamics
Savage, Martin J.; Shanahan, Phiala E.; Tiburzi, Brian C.; Wagman, Michael L.; Winter, Frank; Beane, Silas R.; Chang, Emmanuel; Davoudi, Zohreh; Detmold, William; Orginos, Kostas; Nplqcd Collaboration
2017-08-01
The nuclear matrix element determining the p p →d e+ν fusion cross section and the Gamow-Teller matrix element contributing to tritium β decay are calculated with lattice quantum chromodynamics for the first time. Using a new implementation of the background field method, these quantities are calculated at the SU(3) flavor-symmetric value of the quark masses, corresponding to a pion mass of mπ˜806 MeV . The Gamow-Teller matrix element in tritium is found to be 0.979(03)(10) at these quark masses, which is within 2 σ of the experimental value. Assuming that the short-distance correlated two-nucleon contributions to the matrix element (meson-exchange currents) depend only mildly on the quark masses, as seen for the analogous magnetic interactions, the calculated p p →d e+ν transition matrix element leads to a fusion cross section at the physical quark masses that is consistent with its currently accepted value. Moreover, the leading two-nucleon axial counterterm of pionless effective field theory is determined to be L1 ,A=3.9 (0.2 )(1.0 )(0.4 )(0.9 ) fm3 at a renormalization scale set by the physical pion mass, also agreeing within the accepted phenomenological range. This work concretely demonstrates that weak transition amplitudes in few-nucleon systems can be studied directly from the fundamental quark and gluon degrees of freedom and opens the way for subsequent investigations of many important quantities in nuclear physics.
McCarty, George
1982-01-01
How THIS BOOK DIFFERS This book is about the calculus. What distinguishes it, however, from other books is that it uses the pocket calculator to illustrate the theory. A computation that requires hours of labor when done by hand with tables is quite inappropriate as an example or exercise in a beginning calculus course. But that same computation can become a delicate illustration of the theory when the student does it in seconds on his calculator. t Furthermore, the student's own personal involvement and easy accomplishment give hi~ reassurance and en couragement. The machine is like a microscope, and its magnification is a hundred millionfold. We shall be interested in limits, and no stage of numerical approximation proves anything about the limit. However, the derivative of fex) = 67.SgX, for instance, acquires real meaning when a student first appreciates its values as numbers, as limits of 10 100 1000 t A quick example is 1.1 , 1.01 , 1.001 , •••• Another example is t = 0.1, 0.01, in the functio...
Energy Technology Data Exchange (ETDEWEB)
Merouane, S.; Djouadi, Z.; Le Sergeant d' Hendecourt, L., E-mail: sihane.merouane@ias.u-psud.fr [Institut d' Astrophysique Spatiale, CNRS, UMR-8617, Université Paris Sud, Bâtiment 121, F-91405 Orsay Cedex (France)
2014-01-10
Interplanetary dust particles (IDPs) are among the most pristine extraterrestrial samples available in the laboratory for analyses with moderate to high spatial- and spectral-resolution spectroscopic techniques. Their composition can provide precious information on the early stages of the solar nebula as well as on the processes on the surfaces of different small bodies in the solar system from which IDPs originate. In this work, we have analyzed six anhydrous IDPs and six stratospheric particles possibly of cosmic origin through infrared (IR) and Raman micro-spectroscopy to study and investigate their silicate and organic components. We find that the length/ramification of the aliphatic organics given by the CH{sub 2}/CH{sub 3} ratios in the IDPs is closely linked to the silicate family (pyroxene or olivine) present in the samples. Both IR and Raman data suggest that this relation is not correlated with either aqueous (as evidenced by the absence of aqueous related minerals) or thermal processes (as deduced from Raman measurements). Therefore, this observation might be related to the initial path of formation of the organics on the silicate surfaces, thus tracing a possible catalytic role that silicates would play in the formation and/or ramification of organic matter in the primitive nebula.
The Seismic risk perception in Italy deduced by a statistical sample
Crescimbene, Massimo; La Longa, Federica; Camassi, Romano; Pino, Nicola Alessandro; Pessina, Vera; Peruzza, Laura; Cerbara, Loredana; Crescimbene, Cristiana
2015-04-01
In 2014 EGU Assembly we presented the results of a web a survey on the perception of seismic risk in Italy. The data were derived from over 8,500 questionnaires coming from all Italian regions. Our questionnaire was built by using the semantic differential method (Osgood et al. 1957) with a seven points Likert scale. The questionnaire is inspired the main theoretical approaches of risk perception (psychometric paradigm, cultural theory, etc.) .The results were promising and seem to clearly indicate an underestimation of seismic risk by the italian population. Based on these promising results, the DPC has funded our research for the second year. In 2015 EGU Assembly we present the results of a new survey deduced by an italian statistical sample. The importance of statistical significance at national scale was also suggested by ISTAT (Italian Statistic Institute), considering the study as of national interest, accepted the "project on the perception of seismic risk" as a pilot study inside the National Statistical System (SISTAN), encouraging our RU to proceed in this direction. The survey was conducted by a company specialised in population surveys using the CATI method (computer assisted telephone interview). Preliminary results will be discussed. The statistical support was provided by the research partner CNR-IRPPS. This research is funded by Italian Civil Protection Department (DPC).
Martian low-altitude magnetic topology deduced from MAVEN/SWEA observations
Xu, Shaosui; Mitchell, David; Liemohn, Michael; Fang, Xiaohua; Ma, Yingjuan; Luhmann, Janet; Brain, David; Steckiewicz, Morgane; Mazelle, Christian; Connerney, Jack; Jakosky, Bruce
2017-02-01
The Mars Atmosphere and Volatile Evolution mission has obtained comprehensive particle and magnetic field measurements. The Solar Wind Electron Analyzer provides electron energy-pitch angle distributions along the spacecraft trajectory that can be used to infer magnetic topology. This study presents pitch angle-resolved electron energy shape parameters that can distinguish photoelectrons from solar wind electrons, which we use to deduce the Martian magnetic topology and connectivity to the dayside ionosphere. Magnetic topology in the Mars environment is mapped in three dimensions for the first time. At low altitudes (connections through cross-terminator closed field lines than in the south. Although draped field lines with 100 km amplitude vertical fluctuations that intersect the electron exobase ( 160-220 km) in two locations could appear to be closed at the spacecraft, a more likely explanation is provided by crustal magnetic fields, which naturally have the required geometry. Around 30% of the time, we observe open field lines from 200 to 400 km, which implies three distinct topological layers over the northern hemisphere: closed field lines below 200 km, open field lines with foot points at lower latitudes that pass over the northern hemisphere from 200 to 400 km, and draped interplanetary magnetic field above 400 km. This study also identifies open field lines with one end attached to the dayside ionosphere and the other end connected with the solar wind, providing a path for ion outflow.
Deducing the 237U(n,f) cross-section using the Surrogate Ratio Method
Energy Technology Data Exchange (ETDEWEB)
Burke, J T; Bernstein, L A; Escher, J; Ahle, L; Church, J A; Dietrich, F S; Moody, K J; Norman, E B; Phair, L; Fallon, P; Clark, R M; Deleplanque, M A; Descovich, M; Cromaz, M; Lee, I Y; Macchiavelli, A O; McMahan, M A; Moretto, L G; Rodriguez-Vieitez, E; Stephens, F S; Ai, H; Beausang, C; Cridder, B
2005-12-29
The authors have deduced the cross section for {sup 237}U(n,f) over an equivalent neutron energy range from 0 to 20 MeV using the Surrogate Ratio method. A 55 MeV {sup 4}He beam from the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory was used to induce fission in the following reactions: {sup 238}U({alpha},{alpha}{prime}f) and {sup 236}U({alpha},{alpha}{prime}f). The {sup 238}U reaction was a surrogate for {sup 237}U(n,f) and the {sup 236}U reaction was used as a surrogate for {sup 235}U(n,f). Scattered alpha particles were detected in a fully depleted segmented silicon telescope array (STARS) over an angle range of 35{sup o} to 60{sup o} with respect to the beam axis. The fission fragments were detected in a third independent silicon detector located at backward angles between 106{sup o} and 131{sup o}.
Institute of Scientific and Technical Information of China (English)
James G Brasseur; Mark A Nicosia; Anupam Pal; Larr S Miller
2007-01-01
We summarize from previous works the functions of circular vs. longitudinal muscle in esophageal peristaltic bolus transport using a mix of experimental data, the conservation laws of mechanics and mathematical modeling. Whereas circular muscle tone generates radial closure pressure to create a local peristaltic closure wave, longitudinal muscle tone has two functions, one physiological with mechanical implications, and one purely mechanical. Each of these functions independently reduces the tension of individual circular muscle fibers to maintain closure as a consequence of shortening of longitudinal muscle locally coordinated with increasing circular muscle tone. The physiological function is deduced by combining basic laws of mechanics with concurrent measurements of intraluminal pressure from manometry, and changes in cross sectional muscle area from endoluminal ultrasound from which local longitudinal shortening (LLS) can be accurately obtained. The purely mechanical function of LLS was discovered from mathematical modeling of peristaltic esophageal transport with the axial wall motion generated by LLS. Physiologically, LLS concentrates circular muscle fibers where closure pressure is highest.However, the mechanical function of LLS is to reduce the level of pressure required to maintain closure. The combined physiological and mechanical consequences of LLS are to reduce circular muscle fiber tension and power by as much as 1/10 what would be required for peristalsis without the longitudinal muscle layer, a tremendous benefit that may explain the existence of longitudinal muscle fiber in the gut. We also review what is understood of the role of longitudinal muscle in esophageal emptying, reflux and pathology.
Radiation pressure on a submerged absorptive partial reflector deduced from the Doppler shift
Mansuripur, Masud
2012-01-01
When a light pulse is reflected from a mirror, energy and momentum are exchanged between the electromagnetic field and the material medium. The resulting change in the energy of the reflected photons is directly related to their Doppler shift arising from the change in the state of motion of the mirror. Similarly, the Doppler shift of photons that enter an absorber is intimately tied to the kinetic energy and momentum acquired by the absorber in its interaction with the incident light. The argument from the Doppler shift yields expressions for the exchanged energy and momentum that are identical with those obtained from Maxwell's equations and the Lorentz law of force, despite the fact that the physical bases of the two methods are fundamentally different. Here we apply the Doppler shift argument to a submerged partial reflector (one that absorbs a fraction of the incident light), deducing in the process the magnitude of the photon momentum within the submerging medium. We also discuss the case of the submerg...
Deducing radiation pressure on a submerged mirror from the Doppler shift
Mansuripur, Masud
2012-01-01
Radiation pressure on a flat mirror submerged in a transparent liquid, depends not only on the refractive index n of the liquid, but also on the phase angle psi_0 of the Fresnel reflection coefficient of the mirror, which could be anywhere between 0^{\\circ} and 180^{\\circ}. Depending on the value of psi_0, the momentum per incident photon picked up by the mirror covers the range between the Abraham and Minkowski values, i.e., the interval (2\\hbarw_0/nc,2n\\hbarw_0/c). Here \\hbar is the reduced Planck constant, w_0 is the frequency of the incident photon, and c is the speed of light in vacuum. We argue that a simple experimental setup involving a dielectric slab of refractive index n, a vibrating mirror placed a short distance behind the slab, a collimated, monochromatic light beam illuminating the mirror through the slab, and an interferometer to measure the phase of the reflected beam, is all that is needed to deduce the precise magnitude of the radiation pressure on a submerged mirror. In the proposed experi...
PAS domain of the deduced Org35 protein mediates the interaction with NifA
Institute of Scientific and Technical Information of China (English)
TU Ran; CUI Yanhua; CHEN Sanfeng; LI Jilun
2006-01-01
NifA in Azospirillum brasilense plays a key role in regulating the synthesis of nitrogenase in response to ammonia and oxygen available. Recently,our laboratory has identified four clones, whose gene prodcuts interact with NifA, from A. brasilense Sp7genomic libraries by using the yeast two-hybrid system with NifA as bait. We are interested in clone S35,one of the four clones, because it contains a PAS-domain coding region. The entire open reading frame (ORF) for the PAS domain-containing protein was isolated and designated as org35 here. org35gene is 2211-bp long and encodes a protein of 736aa with a predicted molecular weight of about 78.4 kD.The predicted amino acid sequence of org35 has similarity to some two-component sensor kinase/response regulator hybrids of bacteria. Structural analyses showed that Org35 comprises at least three discrete conserved domains: the N-terminal PAS, the central histidine protein kinase (HPK) and the C-terminal response regulator (RR). The PAS domain of the deduced Org35 protein was found to interact directly with NifA, but the central HPK and the C-terminal RR domains of Org35 were not. These results indicated that interaction between NifA and Org35 was mediated by PAS domain.
F-region Pedersen conductivity deduced using the TIMED/GUVI limb retrievals
Directory of Open Access Journals (Sweden)
Y. Zhang
2006-07-01
Full Text Available As a proxy of the Rayleigh-Taylor instability growth rate for equatorial plasma bubbles, we investigate the flux-tube integrated F-region Pedersen conductivity (ΣPF using the electron density profiles (EDPs provided by the Global Ultraviolet Imager (GUVI on board the Thermosphere Ionosphere and Mesosphere Energetics and Dynamics (TIMED satellite. The investigation is conducted using the EDPs obtained in the Atlantic sector at 19:00-22:00 LT during 4–17 August and 6-16 December 2002. The seasonal difference of the strength and location of the equatorial ionization anomalies (EIAs induces a significant difference in the deduced ΣPF. Much stronger EIAs are created at higher altitudes and latitudes in December rather than in August. At 19:00–20:00 LT, the peak value of the ΣPF has 23 mhos at 1100 km apex height during 14–16 December and 18mhos at 600 km during 15–17 August. The ΣPF decreases as local time progresses. Therefore, ΣPF provides a preferred condition for the growth of bubbles to higher altitudes at 19:00-20:00 LT than at later hours, in December rather than in August in the Atlantic sector.
Yue, G. K.; Poole, L. R.; Wang, P.-H.; Chiou, E. W.
1994-01-01
Water vapor concentrations obtained by the Stratospheric Aerosol and Gas Experiment 2 (SAGE 2) and collocated temperatures provided by the National Meteorological Center (NMC) from 1986 to 1990 are used to deduce seasonally and zonally averaged acidity, density, and refractive index of stratospheric aerosols. It is found that the weight percentage of sulfuric acid in the aerosols increases from about 60 just above the tropopause to about 86 at 35 km. The density increases from about 1.55 to 1.85 g/cu cm between the same altitude limits. Some seasonal variations of composition and density are evident at high latitudes. The refractive indices at 1.02, 0.694, and 0.532 micrometers increase, respectively, from about 1.425, 1.430, and 1.435 just above the tropopause to about 1.445, 1.455, and 1.458 at altitudes above 27 km, depending on the season and latitude. The aerosol properties presented can be used in models to study the effectiveness of heterogeneous chemistry, the mass loading of stratospheric aerosols, and the extinction and backscatter of aerosols at different wavelengths. Computed aerosol surface areas, rate coefficients for the heterogeneous reaction ClONO2 + H2O yields HOCl + HNO3 and aerosol mass concentrations before and after the Pinatubo eruption in June 1991 are shown as sample applications.
Optimizing Network Routing by Deducing a QoS Metric Using Rough Sets
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Ali.A.Sakr,
2010-07-01
Full Text Available The routing within networks, must satisfy the QoS metrics. In traditional data networks, routing is concerned on connectivity or cost. Routing protocols usually characterize the network with one or more metric(s. However, in order to support a wide range of QoS requirements, routing protocols need to have a more complex model. Thenetwork is characterized with multiple metrics such as bandwidth, delay, jitters, loss rate, authentication, security,…etc. This complex model necessitates a long time to proceed. The Rough Set Theory (RST is applied to reduce these metrics successfully and decide the most effective ones. In this paper, RST is applied to reduce the online metrics that are reported by Routing Information Protocols (RIP. The paper represents information about network elements (links, or nodes to obtain the Quality of Service (QoS core [1]. ROSETTA software is applied to deduce a QoS metric as a substitution for all routing metrics. This metric is used to select the optimal routes. The results confirm that the proposed metric is adequately suit for selecting the proper routes.
Deducing the 237U(n,f) cross-section using the Surrogate Ratio Method
Energy Technology Data Exchange (ETDEWEB)
Burke, J T; Bernstein, L A; Escher, J; Ahle, L; Church, J A; Dietrich, F; Moody, K J; Norman, E B; Phair, L W; Fallon, P; Clark, R; Delaplanque, M; Descovich, M; Cromaz, M; Lee, I Y; Macchiavelli, A O; McMahan, M A; Moretto, L G; Rodriguez-Vieitez, E; Stephens, F S
2005-08-16
The authors have deduced the {sup 237}U(n,f) cross-section over an equivalent neutron energy range of 0 to 20 MeV using the Surrogate Ratio method. A 55 MeV {sup 4}He{sup 2+} beam from the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory was used to induce fission in the following reactions {sup 238}U({alpha},{alpha}'f) and {sup 236}U({alpha},{alpha}'f). The {sup 238}U reaction was a surrogate for {sup 237}U(n,f) and the {sup 236}U reaction was used as a surrogate for {sup 235}U(n,f). The energies of the scattered alpha particles were detected in a fully depleted segmented silicon telescope array (STARS) over an angle range of 35{sup o} to 60{sup o} with respect to the beam axis. The fission fragments were detected in a third independent silicon detector located at backward angles between 106{sup o} to 131{sup o}.
Hysteresis Loop for a No-loaded, Delta-connected Transformer Model Deduced from Measurements
Corrodi, Yves; Kamei, Kenji; Kohyama, Haruhiko; Ito, Hiroki
At a transformer's steady-state condition, whereby a transformer and its load are constantly supplied by a sinusoidal source, the current-flux pair within the transformer core and its windings will cycle along a hysteresis loop. This nonlinear current-flux characteristic becomes important while at transformer gets reenergized. A remaining residual flux and the fact that a transformer is typically used up to its saturation level can lead to high-amplitude magnetizing inrush currents and associated voltage disturbances. These disturbances can be reduced by controlled transformer switching. In order to pre-evaluate the effect of a specific controlled transformer energization, pre-simulations can be applied. In that case the hysteresis loop and its saturation characteristic will become the most important model parameter. If the corresponding manufacturer specifications are not available a standard hysteresis loops can be used, but might come up with an inaccurate simulation result. Therefore, this paper analyses the measured 3-phase currents from two delta-connected power transformers by “Fourier Series” in order to deduce a single-phase hysteresis loop, which can be implemented into a typical 3-phase transformer model. Additionally, the saturation behavior of a power-transformer will be estimated and a comparison of ATP/EMTP simulations will conclude this paper.
Calculation of Thermodynamic Parameters for Freundlich and Temkin Isotherm Models
Institute of Scientific and Technical Information of China (English)
ZHANGZENGQIANG; ZHANGYIPING; 等
1999-01-01
Derivation of the Freundlich and Temkin isotherm models from the kinetic adsorption/desorption equations was carried out to calculate their thermodynamic equilibrium constants.The calculation formulase of three thermodynamic parameters,the standard molar Gibbs free energy change,the standard molar enthalpy change and the standard molar entropy change,of isothermal adsorption processes for Freundlich and Temkin isotherm models were deduced according to the relationship between the thermodynamic equilibrium constants and the temperature.
Aminzadeh, Milad; Breitenstein, Daniel; Or, Dani
2017-07-01
The intermittent nature of turbulent airflow interacting with the surface is readily observable in fluctuations of the surface temperature resulting from the thermal imprints of eddies sweeping the surface. Rapid infrared thermography has recently been used to quantify characteristics of the near-surface turbulent airflow interacting with the evaporating surfaces. We aim to extend this technique by using single-point rapid infrared measurements to quantify properties of a turbulent flow, including surface exchange processes, with a view towards the development of an infrared surface anemometer. The parameters for the surface-eddy renewal (α and β ) are inferred from infrared measurements of a single-point on the surface of a heat plate placed in a wind tunnel with prescribed wind speeds and constant mean temperatures of the surface. Thermally-deduced parameters are in agreement with values obtained from standard three-dimensional ultrasonic anemometer measurements close to the plate surface (e.g., α = 3 and β = 1/26 (ms)^{-1} for the infrared, and α = 3 and β = 1/19 (ms)^{-1} for the sonic-anemometer measurements). The infrared-based turbulence parameters provide new insights into the role of surface temperature and buoyancy on the inherent characteristics of interacting eddies. The link between the eddy-spectrum shape parameter α and the infrared window size representing the infrared field of view is investigated. The results resemble the effect of the sampling height above the ground in sonic anemometer measurements, which enables the detection of larger eddies with higher values of α . The physical basis and tests of the proposed method support the potential for remote quantification of the near-surface momentum field, as well as scalar-flux measurements in the immediate vicinity of the surface.
A novel computational framework for deducing muscle synergies from experimental joint moments
Directory of Open Access Journals (Sweden)
Anantharaman eGopalakrishnan
2014-12-01
Full Text Available Prior experimental studies have hypothesized the existence of a ‘muscle synergy’ based control scheme for producing limb movements and locomotion in vertebrates. Such synergies have been suggested to consist of fixed muscle grouping schemes with the co-activation of all muscles in a synergy resulting in limb movement. Quantitative representations of these groupings (termed muscle weightings and their control signals (termed synergy controls have traditionally been derived by the factorization of experimentally measured EMG. This study presents a novel approach for deducing these weightings and controls from inverse dynamic joint moments that are computed from an alternative set of experimental measurements – movement kinematics and kinetics. This technique was applied to joint moments for healthy human walking at 0.7 and 1.7 m/s, and two sets of ‘simulated’ synergies were computed based on two different criteria (1 synergies were required to minimize errors between experimental and simulated joint moments in a musculoskeletal model (pure-synergy solution (2 along with minimizing joint moment errors, synergies also minimized muscle activation levels (optimal-synergy solution. On comparing the two solutions, it was observed that the introduction of optimality requirements (optimal-synergy to a control strategy solely aimed at reproducing the joint moments (pure-synergy did not necessitate major changes in the muscle grouping within synergies or the temporal profiles of synergy control signals. Synergies from both the simulated solutions exhibited many similarities to EMG derived synergies from a previously published study, thus implying that the analysis of the two different types of experimental data reveals similar, underlying synergy structures.
Yokoyama, I.; Mena, M.
1991-07-01
Previous studies of La Primavera caldera have mostly been based on surface geology and topography. Since 1980, many wells, exploring for geothermal energy, have reached depths of about 2 to 3 km at the center of the caldera. The results of the drillings, together with those of the gravity surveys, provide information about the subsurface structure of the caldera, and shed light on its formation. The drilling results and gravity anomalies at La Primavera caldera and San Marcos, located at about 40 km distance from the caldera, suggest that regional gravity anomalies can be interpreted in terms of depths of the granitic basements: the basement beneath La Primavera caldera is about 3 km deep and consists of roughly the same horizon as that beneath San Marcos. The drilling results within the caldera reveal that the depth of the caldera fills ranges from 0.3 to 1 km at the drilling sites. The andesite basement, about 1 km deep, remains approximately horizontal, and the granitic basement has a depth of about 3 km. The surface topographies, such as the postcaldera domes, scarcely disturb the subsurface strata. The local gravity anomalies show two lows within the caldera reflecting the configuration of caldera bottom, two funnel-shaped depressions, one of which corresponds to a vent of the Tala tuff deduced from geological observations. The mass deficiency within the caldera estimated from the gravity anomaly, satisfies the general relationship that the mass deficiency is proportional to the caldera diameter cubed. This means that caldera structure is three-dimensional: the larger the diameter, the deeper the funnel-shape. At present this argument may be limited to funnel-shaped calderas.
Deducing growth mechanisms for minerals from the shapes of crystal size distributions
Eberl, D.D.; Drits, V.A.; Srodon, J.
1998-01-01
Crystal size distributions (CSDs) of natural and synthetic samples are observed to have several distinct and different shapes. We have simulated these CSDs using three simple equations: the Law of Proportionate Effect (LPE), a mass balance equation, and equations for Ostwald ripening. The following crystal growth mechanisms are simulated using these equations and their modifications: (1) continuous nucleation and growth in an open system, during which crystals nucleate at either a constant, decaying, or accelerating nucleation rate, and then grow according to the LPE; (2) surface-controlled growth in an open system, during which crystals grow with an essentially unlimited supply of nutrients according to the LPE; (3) supply-controlled growth in an open system, during which crystals grow with a specified, limited supply of nutrients according to the LPE; (4) supply- or surface-controlled Ostwald ripening in a closed system, during which the relative rate of crystal dissolution and growth is controlled by differences in specific surface area and by diffusion rate; and (5) supply-controlled random ripening in a closed system, during which the rate of crystal dissolution and growth is random with respect to specific surface area. Each of these mechanisms affects the shapes of CSDs. For example, mechanism (1) above with a constant nucleation rate yields asymptotically-shaped CSDs for which the variance of the natural logarithms of the crystal sizes (??2) increases exponentially with the mean of the natural logarithms of the sizes (??). Mechanism (2) yields lognormally-shaped CSDs, for which ??2 increases linearly with ??, whereas mechanisms (3) and (5) do not change the shapes of CSDs, with ??2 remaining constant with increasing ??. During supply-controlled Ostwald ripening (4), initial lognormally-shaped CSDs become more symmetric, with ??2 decreasing with increasing ??. Thus, crystal growth mechanisms often can be deduced by noting trends in ?? versus ??2 of CSDs for
VONCK, J; VANBRUGGEN, EFJ
1992-01-01
The architecture of alcohol oxidase crystalloids occurring in vivo in the peroxisomes of methylotrophic yeasts was deduced from electron micrographs of similar crystals of the Hansenula polymorpha enzyme grown in vitro. Three characteristic views of the crystal are observed, as well as single layers
Spectroscopy of the doubly magic nucleus {sup 100}Sn and its decay
Energy Technology Data Exchange (ETDEWEB)
Hinke, Christoph B.
2010-07-23
}{sub 0}}=3.29{+-}0.20 MeV. The resultant Gamow-Teller transition strength in the decay of {sup 100}Sn turned out to be a surprisingly high value of B{sub GT}=9.1{sup +4.8}{sub -2.3}. In the daughter nucleus {sup 100}In five gamma rays with transition energies of E{sub {gamma}}=96 keV, 141 keV, 436 keV, 1297 keV and 2048 keV deexciting the populated 1{sup +}-state after the beta decay of {sup 100}Sn could be observed for the first time. Different scenarios for the level structure in {sup 100}In are discussed but can unfortunately not be distinguished on the basis of the present data. For each scenario a ground state to ground state Q{sub EC} value of the decay was calculated. (orig.)
Clévédé, E.; Bouin, M.-P.; Bukchin, B.; Mostinskiy, A.; Patau, G.
2004-12-01
This paper illustrates the use of integral estimates given by the stress glut rate moments of total degree 2 for constraining the rupture scenario of a large earthquake in the particular case of the 1999 Izmit mainshock. We determine the integral estimates of the geometry, source duration and rupture propagation given by the stress glut rate moments of total degree 2 by inverting long-period surface wave (LPSW) amplitude spectra. Kinematic and static models of the Izmit earthquake published in the literature are quite different from one another. In order to extract the characteristic features of this event, we calculate the same integral estimates directly from those models and compare them with those deduced from our inversion. While the equivalent rupture zone and the eastward directivity are consistent among all models, the LPSW solution displays a strong unilateral character of the rupture associated with a short rupture duration that is not compatible with the solutions deduced from the published models. With the aim of understand this discrepancy, we use simple equivalent kinematic models to reproduce the integral estimates of the considered rupture processes (including ours) by adjusting a few free parameters controlling the western and eastern parts of the rupture. We show that the joint analysis of the LPSW solution and source tomographies allows us to elucidate the scattering of source processes published for this earthquake and to discriminate between the models. Our results strongly suggest that (1) there was significant moment released on the eastern segment of the activated fault system during the Izmit earthquake; (2) the apparent rupture velocity decreases on this segment.
Cristea, A L; Deutsch, I; Copelovici, Y
1992-01-01
By a qualitative analysis of the solutions of the mathematical model equations (describing the morbidity and susceptibility evolution in a viral epidemics), approximate formulae for the extreme values of the variables and for the duration of the main phases of a multiannual cycle are deduced. These formulae were validated by numerical simulation of the solutions, leading to the exact values of the mentioned essential characteristics of the diseases propagation.
Jenny, Lee; Pang, Dan-Yang; Han, Yin-Lu; B. Tsang, M.
2014-09-01
Global phenomenological GDP08 and microscopic helium-3 optical model potentials have been recently derived. We evaluate these two potential sets by comparing the elastic scattering data of 25 MeV 3He on 16O, 18O, 19F, 23Na, 24Mg, 25Mg, 26Mg, 27Al, 28Si, 30Si, 31P, 32S, 34S, 35Cl, 37Cl, and 39K isotopes. Using the deuteron angular distributions calculated with the distorted wave Born approximation model, we extract the ground-state proton spectroscopic factors from (3He, d) reactions on the same set of nuclei. The extracted proton spectroscopic factors are compared with the large-basis shell-model calculations.
Fuchs, K.; Tittgemeyer, M.; Ryberg, T.; Wenzel, F.; Mooney, W.
2002-01-01
We infer the fine structure of a sub-Moho boundary layer (SMBL) at the top of the lithospheric mantle from high-resolution seismic observations of Peaceful Nuclear Explosions (PNE) on superlong-range profiles in Russia. Densely recorded seismograms permit recognition of previously unknown features of teleseismic propagation of the well known Pn and Sn phases, such as a band of incoherent, scattered, high-frequency seismic energy, developing consistently from station to station, apparent velocities of sub-Moho material, and high-frequency energy to distances of more than 3000 km with a coda band, incoherent at 10 km spacing and yet consistently observed to the end of the profiles. Estimates of the other key elements of the SMBL were obtained by finite difference calculations of wave propagation in elastic 2D models from a systematic grid search through parameter space. The SMBL consists of randomly distributed, mild velocity fluctuations of 2% or schlieren of high aspect ratios (???40) with long horizontal extent (???20 km) and therefore as thin as 0.5 km only; SMBL thickness is 60-100 km. It is suggested that the SMBL is of global significance as the physical base of the platewide observed high-frequency phases Pn and Sn. It is shown that wave propagation in the SMBL waveguide is insensitive to the background velocity distribution on which its schlieren are superimposed. This explains why the Pn and Sn phases traverse geological provinces of various age, heat flow, crustal thickness, and tectonic regimes. Their propagation appears to be independent of age. temperature, pressure, and stress. Dynamic stretching of mantle material during subduction or flow, possibly combined with chemical differentiation have to be considered as scale-forming processes in the upper mantle. However, it is difficult to distinguish with the present sets of Pn/Sn array data whether (and also where) the boundary layer is a frozen-in feature of paleo-processes or whether it is a response to
Göçmengil, Gönenç; Karacık, Zekiye; Genç, Ş. Can; Prelevic, Dejan
2016-04-01
Middle Eocene Tokat and Sivas volcanic successions occur within the İzmir-Ankara-Erzincan suture zone. Different models are suggested for the development of the middle Eocene volcanism such as post-collisional, delamination and slab-breakoff models as well as the arc magmatism. In both areas, volcanic units cover all the basement units with a regional disconformity and comprise lavas spanning a compositional range from mainly basalt-basaltic andesite to a lesser amount trachyte. Here, we report mineral chemistry of different basaltic lavas through transect from northern continent (Tokat region, Pontides) to southern continent (Sivas region, Kırşehir block) to deduce the characteristics of the magma chamber processes which are active during the middle Eocene. Basaltic lavas include olivine bearing basalts (Ol-basalt: ± olivine + clinopyroxene + plagioclase); amphibole bearing basaltic andesite (Amp-basaltic andesite: amphibole + clinopyroxene + plagioclase ± biotite) and pyroxene bearing basaltic andesite (Px-basaltic andesite: clinopyroxene + plagioclase). Microlitic, glomeroporphyric and pilotaxitic texture are common. Clinopyroxene phenocrystals (macro ≥ 750 μm and micro ≤300 μm) are common in all three lava series which are investigated by transecting core to rim compositional profiles. They are generally augite and diopside; euhedral to subhedral in shape with oscillatory, normal and reverse zoning patterns. Also, all clinopyroxene phenocrystals are marked by moderately high Mg# (for Ol-basalt: 67-91; avg. 80; Amp-basaltic andesite: 76-83, avg: 80; Px -basaltic andesite 68-95, avg: 81). In Ol-basalt, clinopyroxene phenocrystals show normal zonation (high Mg# cores and low Mg# rims). In Amp-basaltic andesite, clinopyroxenes are generally homogenous in composition with minor variation of Mg# towards the rims. On the contrary, in Px-basaltic andesite, clinopyroxene macro phenocrystals show reverse zonation with the core with low Mg# and the rims with
An interpretation of ion composition diurnal variation deduced from EISCAT observations
Energy Technology Data Exchange (ETDEWEB)
Mikhailov, A.V. [Rossijskaya Akademiya Nauk, Troitsk (RU). Inst. Zemnogo Magnetizma, Ionosfery i Rasprostraneniya Radiovoln (IZMIRAN); Kofman, W. [Lab. de Planetologie de Grenoble, Grenoble (France)
2001-03-01
Physical interpretation is made of the O{sup +}/Ne diurnal variations in summer, revealed by Litvine et al. (1998) from the EISCAT observations. It is shown that the observed anti-correlation between the Z{sub 50} parameter, corresponding to the transition region between 50% of molecular and atomic ions, and the width D{sub z} of the transition, defined as the altitude width between 10% and 90% of the O{sup +}/Ne ratio, can be reproduced in model calculations and the result of different recombination laws (quadratic in the lower and linear in the upper ionosphere) as well as diurnal variations in the photoionization rates. (orig.)
Decadal variability in core surface flows deduced from geomagnetic observatory monthly means
DEFF Research Database (Denmark)
Whaler, K. A.; Olsen, Nils; Finlay, Chris
2016-01-01
itself changes slowly, its time derivative can be locally (temporally and spatially) large, in particular when and where core surface secular acceleration peaks. Spherical harmonic expansion coefficients of the flows are not well resolved, and many of them are strongly correlated. Averaging functions......Monthly means of the magnetic field measurements at ground observatories are a key data source for studying temporal changes of the core magnetic field. However, when they are calculated in the usual way, contributions of external (magnetospheric and ionospheric) origin may remain, which make them...
The sign of temperature inhomogeneities deduced from time-distance helioseismology
Brüggen, M
2000-01-01
Inhomogeneities in wave propagation conditions near and below the solar surface have been detected by means of time-distance helioseismology. Here we calculate the effect of temperature inhomogeneities on the travel times of sound waves. A temperature increase, e.g. in active regions, not only increases the sound speed but also lengthens the path along which the wave travels because the expansion of the heated layers shifts the upper turning of the waves upward. Using a ray tracing approximation we find that in many cases the net effect of a temperature enhancement is an {\\it increase} of the travel times. We argue that the reduced travel times that are observed are caused by a combination of magnetic fields in the active region and {\\it reduced} subsurface temperatures. Such a reduction may be related to the increased radiative energy loss from small magnetic flux tubes.
An interpretation of ion composition diurnal variation deduced from EISCAT observations
Directory of Open Access Journals (Sweden)
A. V. Mikhailov
Full Text Available Physical interpretation is made of the O^{+}/Ne diurnal variations in summer, revealed by Litvine et al. (1998 from the EISCAT observations. It is shown that the observed anti-correlation between the Z_{50} parameter, corresponding to the transition region between 50% of molecular and atomic ions, and the width D_{z} of the transition, defined as the altitude width between 10% and 90% of the O^{+}/Ne ratio, can be reproduced in model calculations and the result of different recombination laws (quadratic in the lower and linear in the upper ionosphere as well as diurnal variations in the photo-ionization rates.
Key words.Ionosphere (ion chemistry and composition; modeling and forecasting
Rakowski, Andrzej Z; Nakamura, Toshio; Pazdur, Anna
2008-10-01
Radiocarbon concentration in the atmosphere is significantly lower in areas where man-made emissions of carbon dioxide occur. This phenomenon is known as Suess effect, and is caused by the contamination of clean air with non-radioactive carbon from fossil fuel combustion. The effect is more strongly observed in industrial and densely populated urban areas. Measurements of carbon isotope concentrations in a study area can be compared to those from areas of clear air in order to estimate the amount of carbon dioxide emission from fossil fuel combustion by using a simple mathematical model. This can be calculated using the simple mathematical model. The result of the mathematical model followed in this study suggests that the use of annual rings of trees to obtain the secular variations of 14C concentration of atmospheric CO2 can be useful and efficient for environmental monitoring and modeling of the carbon distribution in local scale.
Energy Technology Data Exchange (ETDEWEB)
Zighem, F; Roussigne, Y; Cherif, S-M; Moch, P [Laboratoire des Proprietes Mecaniques et Thermodynamiques des Materiaux, CNRS, Institut Galilee, Universite Paris-Nord, Avenue J-B Clement, 93430 Villetaneuse (France)], E-mail: zighem@galilee.univ-paris13.fr
2008-03-26
A comparative study of thin permalloy films (10.4 nm) interfaced with NiO layers of various thicknesses (6 to 47 nm) is presented. The magnetic parameters deduced from different experimental techniques (Brillouin spectroscopy, ferromagnetic resonance and magnetometric (vibrating sample magnetometry and magneto-optical Kerr effect) investigations) show original characteristics which have not been previously evidenced: (i) for most of the samples studied, the exchange bias field is not parallel or perpendicular to the cooling field, in contrast with the in-plane anisotropy field; (ii) the magnetic properties under an out-of-plane applied magnetic field H do not match the calculated ones derived from the usual expression for the density of magnetic energy. We introduce a phenomenological additional term proportional to cos[{alpha}] where {alpha} is the angle between H and the direction normal to the sample: this non-conventional interaction between NiO and permalloy layers allows us to fit all the experimental data.
Tardieu, François; Parent, Boris
2016-08-29
Growth under water deficit is controlled by short-term mechanisms but, because of numerous feedbacks, the combination of these mechanisms over time often results in outputs that cannot be deduced from the simple inspection of individual mechanisms. It can be analysed with dynamic models in which causal relationships between variables are considered at each time-step, allowing calculation of outputs that are routed back to inputs for the next time-step and that can change the system itself. We first review physiological mechanisms involved in seven feedbacks of transpiration on plant growth, involving changes in tissue hydraulic conductance, stomatal conductance, plant architecture and underlying factors such as hormones or aquaporins. The combination of these mechanisms over time can result in non-straightforward conclusions as shown by examples of simulation outputs: 'over production of abscisic acid (ABA) can cause a lower concentration of ABA in the xylem sap ', 'decreasing root hydraulic conductance when evaporative demand is maximum can improve plant performance' and 'rapid root growth can decrease yield'. Systems of equations simulating feedbacks over numerous time-steps result in logical and reproducible emergent properties that can be viewed as 'meta-mechanisms' at plant level, which have similar roles as mechanisms at cell level.
Institute of Scientific and Technical Information of China (English)
Zhang Yan-Feng; Jia Jin-Feng; Han Tie-Zhu; Tang Zhe; Shen Quan-Tong; Guo Yang; Xue Qi-Kun
2005-01-01
Photoemission study of atomically flat Pb films with a thickness from 15 to 24 monolayers (ML) have been performed within a temperature range 75-270K. Well-defined quantum well states (QWSs) are observed, which exhibit interesting temperature-dependent behaviours. The peak position of the QWSs shifts towards higher binding energy with increasing substrate temperature, whereas the peak width broadens linearly due to enhanced electron-phonon coupling strength (λ). An oscillatory λ with a period of 2ML is deduced. Preliminary analysis shows that the oscillation can be explained in terms of the interface induced phase variations, and is thus a manifestation of the quantum size effects.
The verification of lightning location accuracy in Finland deduced from lightning strikes to trees
Mäkelä, Antti; Mäkelä, Jakke; Haapalainen, Jussi; Porjo, Niko
2016-05-01
We present a new method to determine the ground truth and accuracy of lightning location systems (LLS), using natural lightning strikes to trees. Observations of strikes to trees are being collected with a Web-based survey tool at the Finnish Meteorological Institute. Since the Finnish thunderstorms tend to have on average a low flash rate, it is often possible to identify from the LLS data unambiguously the stroke that caused damage to a given tree. The coordinates of the tree are then the ground truth for that stroke. The technique has clear advantages over other methods used to determine the ground truth. Instrumented towers and rocket launches measure upward-propagating lightning. Video and audio records, even with triangulation, are rarely capable of high accuracy. We present data for 36 quality-controlled tree strikes in the years 2007-2008. We show that the average inaccuracy of the lightning location network for that period was 600 m. In addition, we show that the 50% confidence ellipse calculated by the lightning location network and used operationally for describing the location accuracy is physically meaningful: half of all the strikes were located within the uncertainty ellipse of the nearest recorded stroke. Using tree strike data thus allows not only the accuracy of the LLS to be estimated but also the reliability of the uncertainty ellipse. To our knowledge, this method has not been attempted before for natural lightning.
Directory of Open Access Journals (Sweden)
L. M. Andreassen
2008-10-01
Full Text Available A Landsat Thematic Mapper (TM scene from 2003 covering the Jotunheimen and Breheimen region has been used to map the recent glacier extents using thresholded ratio images (TM3/TM5. Orthoprojected aerial photographs and glacier outlines from digital maps have been used to validate the method and control the results. We further calculated glacier changes by comparing the Landsat-derived 2003 glacier outlines with previous maps and inventories from the 1930s, 1960s and 1980s. Our results confirm that the applied automatic mapping method is robust and agrees with the reference data used. Some manual editing was necessary to correct the outline at ice-lake contacts and at debris covered glaciers. However, for most of the glaciers no corrections were required. The most laborious task has been to assign ID numbers and couple the new Landsat inventory to previous inventories to assess area changes. The glaciers investigated shrank since the 1930s with an overall area reduction of about 23% for 38 glaciers. Since the 1960s the area reduction was 12% for 164 glaciers. Although the general trend is glacier recession, some glaciers have increased their size or remained nearly unchanged over these decades.
The production rate of cosmogenic 21-Ne in chondrites deduced from 81-Kr measurements
Schultz, L.; Freundel, M.
1986-01-01
Cosmogenic Ne-21 is used widely to calculate exposure ages of stone meteorites. In order to do so, the production rate P(21) must be known. This rate, however, is dependent on the chemical composition of the meteorite as well as the mass of, and position within, the meteoroid during its exposure to the cosmic radiation. Even for a mean shielding the production rates determined from measurments of different radionuclides vary by a factor of two. A method that can be used to determine exposure ages of meteorites that avoids shielding and chemical composition corrections is the -81-Kr-Kr-method. However, for chondrites, in many cases, the direct determination of production rates for the Kr isotopes is prevented by the trapped gases and the neutron effects on bromine. Therefore, this method was applied to four eucrite falls and then their 81-Kr-83-Kr-ages were compared to their cosmogenic Ne-21 and Ar-38 concentrations. The eucrites Bouvante-le-Haut, Juvinas, Sioux County, and Stannern were chosen for these measurements because of their similar chemical composition regarding the major elements.
Pomaznoy, Mikhail; Tatkov, Sergey; Katokhin, Alexey; Afonnikov, Dmitry; Babenko, Vladimir; Furman, Dagmara; Brusentsov, Ilya; Belavin, Pavel; Najakshin, Alexandr; Guselnikov, Sergey; Vasiliev, Gennady; Sivkov, Anton; Prokhortchouk, Egor; Skryabin, Konstantin; Mordvinov, Viatcheslav
2013-10-01
The epidemiologically important liver flukes Opisthorchis felineus, Opisthorchis viverrini, and Clonorchis sinensis are of interest to health professionals, epidemiologists, pharmacologists, and molecular biologists. Recently the transcriptomes of the latter two species were intensively investigated. However our knowledge on molecular biology of O. felineus is scarce. We report the first results of the O. felineus transcriptome analysis. We isolated and annotated a total of 2560 expressed sequence tag (EST) sequences from adult O. felineus (deposited within the database of expressed sequence tags (dbEST), under accession numbers GenBank: JK624271-JK626790, JK006511-JK006547, JK649790-JK649792). Clustering and analysis resulted in the detection of 267 contigs. Of the protein sequences deduced from these, 82% had homologs in the NCBI (nr) protein database and 63% contained conserved domains, allowing the functions to be interpreted using the Gene Ontology terms. Comprehensive analysis of Opisthorchiidae- and Trematoda-specific substitutions within amino acid sequences deduced for the proteins myoglobin, vitelline precursor protein, cathepsin F, and 28kDa glutathione transferase was carried out. The gene set of the 32 ribosomal proteins for the three Opisthorchiidae species with the addition of available Schistosoma and Fasciola orthologs was created and is provided in the supplementary. The orthologous gene set created was used for inferring phylogeny within the Trematoda with special attention to interrelations within the Opisthorchiidae. The phylogenetic analysis revealed a closer relationship between C. sinensis and O. viverrini and some divergence of O. felineus from either O. viverrini or C. sinensis.
Scaling law deduced from impact-cratering experiments on basalt targets
Takagi, Y.; Hasegawa, S.; Suzuki, A.
2014-07-01
Since impact-cratering phenomena on planetary bodies were the key process which modified the surface topography and formed regolith layers, many experiments on non-cohesive materials (sand, glass beads) were performed. On the other hand, experiments on natural rocks were limited. Especially, experiments on basalt targets are rare, although basalt is the most common rocky material on planetary surfaces. The reason may be the difficulties of obtaining basalt samples suitable for cratering experiments. Recently, we obtained homogenous and crackless large basalt blocks. We performed systematic cratering experiments using the basalt targets. Experimental Procedure: Impact experiments were performed using a double stage light-gas (hydrogen) gun on the JAXA Sagamihara campus. Spherical projectiles of nylon, aluminum, stainless steel, and tungsten carbide were launched at velocities between 2400 and 6100 m/sec. The projectiles were 1.0 to 7.1 mm in diameter and 0.004 to 0.22 g in mass. The incidence angle was fixed at 90 degrees. The targets were rectangular blocks of Ukrainian basalt. The impact plane was a square with 20-cm sides. The thickness was 9 cm. Samples were cut out from a columnar block so that the impact plane might become perpendicular to the axis of the columnar joint. The mass was about 10.5 kg. The density was 2920 ± 10 kg/m^3 . Twenty eight shots were performed. Three-dimensional shapes of craters were measured by an X-Y stage with a laser displacement sensor (Keyence LK-H150). The interval between the measurement points was 200 micrometer. The volume, depth, and aperture area of the crater were calculated from the 3-D data using analytical software. Since the shapes of the formed craters are markedly asymmetrical, the diameter of the circle whose area is equal to the aperture area was taken as the crater diameter. Results: The diameter, depth, and the volume of the formed craters are normalized by the π parameters. Experimental conditions are also
Parameter-Free Quasiparticle Calculations for YH3
van Gelderen, P.; Bobbert, P. A.; Kelly, P. J.; Brocks, G.
2000-10-01
Electronic structure calculations for YH3 within the local density approximation result in a metallic ground state with the bands at the Fermi energy overlapping by more than 1 eV, whereas a band gap of 2.8 eV is deduced from optical experiments. Here, we report the results of parameter-free GW calculations which predict a fundamental gap of 1 eV. When we take into account electric dipole matrix elements a large optical gap of almost 3 eV is obtained. A combination of photoemission and inverse photoemission spectroscopy could test the prediction of a small fundamental band gap.
Lauben, D.; Cohen, M.; Inan, U.
2012-12-01
We deduce the 3d intra-plasmaspheric distribution of VLF wave power between conjugate regions of strong VLF wave amplitudes as measured by DEMETER for high-power terrestrial VLF transmitters during its ~6-yr lifetime. We employ a mixed WKB/full-wave technique to solve for the primary and secondary electromagnetic and electrostatic waves which are transmitted and reflected from strong cold-plasma density gradients and posited irregularities, in order to match the respective end-point measured amplitude distributions. Energy arriving in the conjugate region and also escaping to other regions of the magnetosphere is note. The resulting 3d distribution allows improved estimates for the long-term average particle scattering induced by terrestrial VLF transmitters.
Pouderoux, Hugo; Proust, Jean-Noël; Lamarche, Geoffroy
2014-01-01
Paleoseismic studies seek to characterise the signature of pre-historical earthquakes by deriving quantitative information from the geological record such as the source, magnitude and recurrence of moderate to large earthquakes. In this study, we provide a ˜16,000 yr-long paleo-earthquake record of the 200 km-long northern Hikurangi Margin, New Zealand, using cm-thick deep-sea turbidites identified in sediment cores. Cores were collected in strategic locations across the margin within three distinct morphological re-entrants - the Poverty, Ruatoria and Matakaoa re-entrants. The turbidite facies vary from muddy to sandy with evidence for rare hyperpycnites interbedded with hemipelagites and tephra. We use the Oxal probabilistic software to model the age of each turbidite, using the sedimentation rate of hemipelagite deduced from well-dated tephra layers and radiocarbon ages measurements on planktonic foraminifera.
A new formula to calculate activity of superoxide dismutase in indirect assays
Zhang, Chen; Bruins, Marieke E.; Yang, Zhi Qiang; Liu, Shu Tao; Rao, Ping Fan
2016-01-01
To calculate superoxide dismutase (SOD) activity rapidly and accurately by indirect SOD assays, a formula based on the ratio of the catalytic speed of SOD to the reaction speed of the indicator with superoxide anion was deduced. The accuracy of this formula was compared with the conventional form
National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Calculator will calculate the total magnetic field, including components (declination, inclination, horizontal intensity, northerly intensity,...
WBN-1 Cycle 10 TPBAR Tritium Release, Deduced From Analysis of RCS Data TTP-1-3046-00, Rev 0
Energy Technology Data Exchange (ETDEWEB)
Shaver, Mark W.; Niehus, Mark T.; Love, Edward F.
2012-02-19
This document contains the calculation of the TPBAR tritium release from the Mark 9.2 design TPBARs irradiated in WBN cycle 10. The calculation utilizes the generalized cycle analysis methodology given in TTP-1-3045 Rev. 0.
DEFF Research Database (Denmark)
Tamke, Martin; Myrup Jensen, Morten; Beetz, Jakob
2014-01-01
that in practice models are no longer solely observed as culmination of knowledge in a 3d representation of future built structures, but as a source of information in itself. Experienced users of BIM want to Find Information within a model or across a set of these and Compare models in order to evaluate states......In recent years, Building Information Models have become commonplace in building profession. The extensive use and increasing experience with BIM models offers new perspectives and potentials for design and planning. A recent stakeholder study conducted by the authors of this paper show...... of a model, differences in separate models or models from different point of time. Current BIM tools support both modes only in a rudimentary form. This paper discusses current modes of information query within and across BIM models, shows beneficial scenarios for building and planning practice through...
DEFF Research Database (Denmark)
Tamke, Martin; Myrup Jensen, Morten; Beetz, Jakob
2014-01-01
In recent years, Building Information Models have become commonplace in building profession. The extensive use and increasing experience with BIM models offers new perspectives and potentials for design and planning. A recent stakeholder study conducted by the authors of this paper show...... of a model, differences in separate models or models from different point of time. Current BIM tools support both modes only in a rudimentary form. This paper discusses current modes of information query within and across BIM models, shows beneficial scenarios for building and planning practice through...... that in practice models are no longer solely observed as culmination of knowledge in a 3d representation of future built structures, but as a source of information in itself. Experienced users of BIM want to Find Information within a model or across a set of these and Compare models in order to evaluate states...
Melis, Nikolaos S.; Miliorizos, Marios N.; Oshoano Aipoh, Hilary
2013-04-01
postulated to reactivate it. For example, structures are selected in the field from the tectonised strata of northern Corfu and from recent geological maps of north western Greece. These data are used in conjunction with the results of stress inversion of focal mechanisms, in order to anticipate and then test the gross senses of fault reactivation. Tests are investigated using structural field techniques and available international striation analysis software modules. The defined framework analysis is applied to both the data from ancient faults, in UK and the focal mechanisms of earthquakes, in Greece. Stress tensors are calculated and fault kinematic histories are evaluated. Hence, this application permits the effects of a modern stress regime to be deduced for a known fault framework, in order to complete and understand fully the kinematic history to the present day. As a corollary, the significant field techniques of tracing major fault lines across regional unconformities and measuring the sense of displacements across these stratigraphic boundaries permit kinematic histories to be defined more precisely in both terranes, than by using only structural techniques.
Energy Technology Data Exchange (ETDEWEB)
Bemer, E.; Vincke, O.; Longuemare, P. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)
2004-07-01
The 'geomechanical log' research project aims at estimating rock mechanical properties from a set of models, whose input data can be deduced from drilling logs and measurements on core samples (if these are available). The key point is to focus on defining relatively general and easy to handle models. In this paper, we propose various analytical models allowing one to estimate poroelastic and failure properties of limestones and sandstones directly from their porosity and, in the specific case of sandstone poroelastic characteristics, their mineralogical content. The properties obtained are in reasonable agreement with experimental data. The second step of the project will be to actually infer the input data for the models (here porosity and mineral content) from drilling logs and to compare the results obtained to tests on core samples. A geomechanical log could then be automatically created from standard logs and help to optimize drilling. We also intend to test the same approaches on rock plastic properties and shale behavior. (authors)
Swem, Lee R.; Swem, Danielle L.; Wingreen, Ned S.; Bassler, Bonnie L.
2008-01-01
Summary Quorum sensing, a process of bacterial cell-cell communication, relies on production, detection, and response to autoinducer signaling molecules. Here we focus on LuxN, a nine transmembrane domain protein from Vibrio harveyi, and the founding example of membrane-bound receptors for acyl-homoserine lactone (AHL) autoinducers. Previously, nothing was known about signal recognition by membrane-bound AHL receptors. We used mutagenesis and suppressor analyses to identify the AHL-binding domain of LuxN, and discovered LuxN mutants that confer decreased and increased AHL sensitivity. Our analysis of dose-response curves of multiple LuxN mutants pins these inverse phenotypes on quantifiable opposing shifts in the free-energy bias of LuxN for its kinase and phosphatase states. To extract signaling parameters, we exploited a strong LuxN antagonist, one of fifteen small-molecule antagonists we identified. We find that quorum-sensing-mediated communication can be manipulated positively and negatively to control bacterial behavior, and that signaling parameters can be deduced from in vivo data. PMID:18692469
Ahmad, Suhail; Jensen, Roy A.
1988-03-01
Metabolic pathways of prokaryotes are more biochemically diverse than is generally recognized. Distinctive biochemical features are shared by phylogenetic clusters. The hierarchical levels of characterstate clustering depends upon evolutionary events which fortuitously became fixed in the genome of a common ancestor. Prokaryotes can now be ordered on a phylogenetic tree. This allows the evolutionary steps that underlie the construction and regulation of appropriately complex biochemical pathways to be traced in an evolutionary progression of prokaryote types that house these pathways. Essentially the approach is to deduce ancestral character states at ever deeper phylogenetic levels, utilizing logical principles of maximum parsimony. The current perspective on the evolution of the biochemical pathway for biosynthesis of aromatic amino acids is developed as a case-in-point model for analyses that should be feasible with many major metabolic systems. Phenylalanine biosynthesis probably arose prior to the addition of branches leading to tyrosine and tryptophan. An evolutionary scenario is developed that begins with non-enzymatic reactions which may have operated in primitive systems, followed by the evolution of an enzymatic system that pre-dated the divergence of major lineages of modern eubacteria (Gram-positive bacteria, Gram-negative purple bacteria, and cyanobacteria).
Deducing the 236Pu(n,f) and 237Pu(n,f) cross sections via the surrogate ratio method
Hughes, R. O.; Beausang, C. W.; Ross, T. J.; Burke, J. T.; Casperson, R. J.; McCleskey, M.; Cooper, N.; Escher, J. E.; Gell, K. B.; Good, E.; Humby, P.; Saastimoinen, A.; Tarlow, T. D.
2013-10-01
The short half-lives associated with certain minor actinide nuclei that are relevant to stockpile stewardship pursuits and the development of next-generation nuclear reactors make direct neutron measurements very challenging. In certain cases, a stable beam and target ``surrogate reaction'' can be used in lieu of the neutron-induced reaction, and the (n,f) cross section can then be deduced indirectly. Agreement between surrogate and direct measurements for (n,f) cross sections in actinide nuclei is usually within 10%. The present work reports on the measurement of the 236Pu(n,f) and 237Pu(n,f) cross sections via 239Pu(p,tf) and 239Pu(p,df) surrogate reactions, respectively. The experiment was performed at the Texas A&M University Cyclotron Facility using a 28.5 MeV proton beam to bombard 239Pu and 235U targets. Outgoing light ions were detected in coincidence with fission fragments using the STAR-LiTe detector array. Results of the analysis will be presented. This work was supported by DoE Grant Numbers: DE-FG52-09NA29454 and DE-FG02-05ER41379 (Richmond), DE-AC52-07NA27344 (LLNL) and DE-FG52-09NA29467 (TAMU).
Institute of Scientific and Technical Information of China (English)
GAO Yuan; WU Jing
2008-01-01
The rocks in the crust are pervaded by stress-aligned fluid-saturated microcracks, and the complex fault tectonics and stress control the configuration of the microcracks, however shear-wave splitting could indicate this kind of characteristics. In this paper, Capital Area Seismograph Network (CASN), the widest scope and highest density of regional seismograph network presently in China, is adopted to deduce the principal compressive stress field distribution pattern from polarizations of fast shear-waves, based on shear-wave splitting analysis. The principal compressive stress in capital area of China is at NE85.7°±41.0° in this study. Compared with the results of principal compressive stress field in North China obtained from other methods, the results in this study are reliable in the principal com-pressive stress field distribution in capital area. The results show that it is an effective way, although it is the first time to directly obtain crustal stress field from seismic anisotropy. It is effectively applied to the zones with dense seismograph stations.
Threlfall, John
2002-01-01
Suggests that strategy choice is a misleading characterization of efficient mental calculation and that teaching mental calculation methods as a whole is not conducive to flexibility. Proposes an alternative in which calculation is thought of as an interaction between noticing and knowledge. Presents an associated teaching approach to promote…
Geochemical Calculations Using Spreadsheets.
Dutch, Steven Ian
1991-01-01
Spreadsheets are well suited to many geochemical calculations, especially those that are highly repetitive. Some of the kinds of problems that can be conveniently solved with spreadsheets include elemental abundance calculations, equilibrium abundances in nuclear decay chains, and isochron calculations. (Author/PR)
Autistic Savant Calendar Calculators.
Patti, Paul J.
This study identified 10 savants with developmental disabilities and an exceptional ability to calculate calendar dates. These "calendar calculators" were asked to demonstrate their abilities, and their strategies were analyzed. The study found that the ability to calculate dates into the past or future varied widely among these…
How Do Calculators Calculate Trigonometric Functions?
Underwood, Jeremy M.; Edwards, Bruce H.
How does your calculator quickly produce values of trigonometric functions? You might be surprised to learn that it does not use series or polynomial approximations, but rather the so-called CORDIC method. This paper will focus on the geometry of the CORDIC method, as originally developed by Volder in 1959. This algorithm is a wonderful…
Importance of parametrizing constraints in quantum-mechanical variational calculations
Chung, Kwong T.; Bhatia, A. K.
1992-01-01
In variational calculations of quantum mechanics, constraints are sometimes imposed explicitly on the wave function. These constraints, which are deduced by physical arguments, are often not uniquely defined. In this work, the advantage of parametrizing constraints and letting the variational principle determine the best possible constraint for the problem is pointed out. Examples are carried out to show the surprising effectiveness of the variational method if constraints are parameterized. It is also shown that misleading results may be obtained if a constraint is not parameterized.
Trümbach, Dietrich; Graf, Cornelia; Pütz, Benno; Kühne, Claudia; Panhuysen, Marcus; Weber, Peter; Holsboer, Florian; Wurst, Wolfgang; Welzl, Gerhard; Deussing, Jan M
2010-11-19
Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is a hallmark of complex and multifactorial psychiatric diseases such as anxiety and mood disorders. About 50-60% of patients with major depression show HPA axis dysfunction, i.e. hyperactivity and impaired negative feedback regulation. The neuropeptide corticotropin-releasing hormone (CRH) and its receptor type 1 (CRHR1) are key regulators of this neuroendocrine stress axis. Therefore, we analyzed CRH/CRHR1-dependent gene expression data obtained from the pituitary corticotrope cell line AtT-20, a well-established in vitro model for CRHR1-mediated signal transduction. To extract significantly regulated genes from a genome-wide microarray data set and to deduce underlying CRHR1-dependent signaling networks, we combined supervised and unsupervised algorithms. We present an efficient variable selection strategy by consecutively applying univariate as well as multivariate methods followed by graphical models. First, feature preselection was used to exclude genes not differentially regulated over time from the dataset. For multivariate variable selection a maximum likelihood (MLHD) discriminant function within GALGO, an R package based on a genetic algorithm (GA), was chosen. The topmost genes representing major nodes in the expression network were ranked to find highly separating candidate genes. By using groups of five genes (chromosome size) in the discriminant function and repeating the genetic algorithm separately four times we found eleven genes occurring at least in three of the top ranked result lists of the four repetitions. In addition, we compared the results of GA/MLHD with the alternative optimization algorithms greedy selection and simulated annealing as well as with the state-of-the-art method random forest. In every case we obtained a clear overlap of the selected genes independently confirming the results of MLHD in combination with a genetic algorithm. With two unsupervised algorithms
Directory of Open Access Journals (Sweden)
Holsboer Florian
2010-11-01
Full Text Available Abstract Background Dysregulation of the hypothalamic-pituitary-adrenal (HPA axis is a hallmark of complex and multifactorial psychiatric diseases such as anxiety and mood disorders. About 50-60% of patients with major depression show HPA axis dysfunction, i.e. hyperactivity and impaired negative feedback regulation. The neuropeptide corticotropin-releasing hormone (CRH and its receptor type 1 (CRHR1 are key regulators of this neuroendocrine stress axis. Therefore, we analyzed CRH/CRHR1-dependent gene expression data obtained from the pituitary corticotrope cell line AtT-20, a well-established in vitro model for CRHR1-mediated signal transduction. To extract significantly regulated genes from a genome-wide microarray data set and to deduce underlying CRHR1-dependent signaling networks, we combined supervised and unsupervised algorithms. Results We present an efficient variable selection strategy by consecutively applying univariate as well as multivariate methods followed by graphical models. First, feature preselection was used to exclude genes not differentially regulated over time from the dataset. For multivariate variable selection a maximum likelihood (MLHD discriminant function within GALGO, an R package based on a genetic algorithm (GA, was chosen. The topmost genes representing major nodes in the expression network were ranked to find highly separating candidate genes. By using groups of five genes (chromosome size in the discriminant function and repeating the genetic algorithm separately four times we found eleven genes occurring at least in three of the top ranked result lists of the four repetitions. In addition, we compared the results of GA/MLHD with the alternative optimization algorithms greedy selection and simulated annealing as well as with the state-of-the-art method random forest. In every case we obtained a clear overlap of the selected genes independently confirming the results of MLHD in combination with a genetic
Beta Decay of the Proton-Rich Nuclei ^{102}Sn and ^{104}Sn
Energy Technology Data Exchange (ETDEWEB)
Karny, M. [University of Warsaw; Batist, L. [St. Petersburg Nuclear Physics Institute; Banu, A. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Becker, F. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Blazhev, A. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Brown, B. A. [Michigan State University, East Lansing; Bruchle, W. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Doring, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Faestermann, T. [Technische Universitat Munchen; Gorska, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Grawe, H. [GSI-Hemholtzzentrum fur Schwerionenforschung, Darmstadt, Germany; Janas, Z. [University of Warsaw; Jungclaus, A. [Universidad Autonoma de Madrid, Madrid; Kavatsyuk, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kavatsyuk, O. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kirchner, R. [Gesellschaft fur Schwerionenforschung (GSI), Germany; La Commara, M. [Universita Federico II and INFN Napoli; Mandal, S. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Mazzocchi, C. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Miernik, K. [University of Warsaw; Mukha, I. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Muralithar, S. [University of Warsaw; Plettner, C. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Plochocki, A. [University of Warsaw; Roeckl, E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Romoli, M. [Universita Federico II and INFN Napoli; Rykaczewski, Krzysztof Piotr [ORNL; Schadel, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Schmidt, K. [University of Warsaw; Schwengner, R. [University of Warsaw; Zylicz, J. [University of Warsaw
2006-01-01
The {beta} decays of {sup 102}Sn and {sup 104}Sn were studied by using high-resolution germanium detectors as well as a Total Absorption Spectrometer (TAS). For {sup 104}Sn, with three new {beta}-delayed {gamma}-rays identified, the total Gamow-Teller strength (BGT) value of 2.7(3) was obtained. For {sup 102}Sn, the {gamma}-{gamma} coincidence data were collected for the first time, allowing us to considerably extend the decay scheme. This scheme was used to unfold the TAS data and to deduce a BGT value of 4.2(8) for this decay. This result is compared to shell model predictions, yielding a hindrance factor of 3.6(7) in agreement with those obtained previously for {sup 98}Cd and {sup 100}In. Together with the latter two, {sup 102}Sn completes the triplet of Z {le} 50, N {ge} 50 nuclei with two proton holes, one proton hole and one neutron particle, and two neutron particles with respect to the doubly magic {sup 100}Sn core.
Beta decay of the exotic $T_z$ = -2 nuclei $^{48}$Fe, $^{52}$Ni and $^{56}$Zn
Orrigo, S E A; Fujita, Y; Gelletly, W; Agramunt, J; Algora, A; Ascher, P; Bilgier, B; Blank, B; Cáceres, L; Cakirli, R B; Ganioğlu, E; Gerbaux, M; Giovinazzo, J; Grévy, S; Kamalou, O; Kozer, H C; Kucuk, L; Kurtukian-Nieto, T; Molina, F; Popescu, L; Rogers, A M; Susoy, G; Stodel, C; Suzuki, T; Tamii, A; Thomas, J C
2016-01-01
The results of a study of the beta decays of three proton-rich nuclei having $T_z$ = -2, namely $^{48}$Fe, $^{52}$Ni and $^{56}$Zn, produced in an experiment carried out at GANIL, are reported. In all the cases we have extracted the half-lives and the total $\\beta$-delayed proton emission branching ratios. We have measured the individual $\\beta$-delayed protons and $\\beta$-delayed $\\gamma$ rays with their branching ratios. Decay schemes have been determined for the three nuclei, and new energy levels are identified in the corresponding daughter nuclei. Competition between $\\beta$-delayed protons and gammas is observed in the de-excitation of the $T$ = 2 Isobaric Analogue States in all three cases. Absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. In addition, we discuss in detail the data analysis taking as a test case $^{56}$Zn, where the exotic $\\beta$-delayed $\\gamma$-proton decay has been observed.
Energy Technology Data Exchange (ETDEWEB)
Nagao, Yoshiharu [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment
1998-03-01
In material testing reactors like the JMTR (Japan Material Testing Reactor) of 50 MW in Japan Atomic Energy Research Institute, the neutron flux and neutron energy spectra of irradiated samples show complex distributions. It is necessary to assess the neutron flux and neutron energy spectra of an irradiation field by carrying out the nuclear calculation of the core for every operation cycle. In order to advance core calculation, in the JMTR, the application of MCNP to the assessment of core reactivity and neutron flux and spectra has been investigated. In this study, in order to reduce the time for calculation and variance, the comparison of the results of the calculations by the use of K code and fixed source and the use of Weight Window were investigated. As to the calculation method, the modeling of the total JMTR core, the conditions for calculation and the adopted variance reduction technique are explained. The results of calculation are shown. Significant difference was not observed in the results of neutron flux calculations according to the difference of the modeling of fuel region in the calculations by K code and fixed source. The method of assessing the results of neutron flux calculation is described. (K.I.)
Explosion Calculations of SN1087
Wooden, Diane H.; Morrison, David (Technical Monitor)
1994-01-01
Explosion calculations of SNT1987A generate pictures of Rayleigh-Taylor fingers of radioactive Ni-56 which are boosted to velocities of several thousand km/s. From the KAO observations of the mid-IR iron lines, a picture of the iron in the ejecta emerges which is consistent with the "frothy iron fingers" having expanded to fill about 50% of the metal-rich volume of the ejecta. The ratio of the nickel line intensities yields a high ionization fraction of greater than or equal to 0.9 in the volume associated with the iron-group elements at day 415, before dust condenses in the ejecta. From the KAO observations of the dust's thermal emission, it is deduced that when the grains condense their infrared radiation is trapped, their apparent opacity is gray, and they have a surface area filling factor of about 50%. The dust emission from SN1987A is featureless: no 9.7 micrometer silicate feature, nor PAH features, nor dust emission features of any kind are seen at any time. The total dust opacity increases with time even though the surface area filling factor and the dust/gas ratio remain constant. This suggests that the dust forms along coherent structures which can maintain their radial line-of-sight opacities, i.e., along fat fingers. The coincidence of the filling factor of the dust and the filling factor of the iron strongly suggests that the dust condenses within the iron, and therefore the dust is iron-rich. It only takes approximately 4 x 10(exp -4) solar mass of dust for the ejecta to be optically thick out to approximately 100 micrometers; a lower limit of 4 x 10(exp -4) solar mass of condensed grains exists in the metal-rich volume, but much more dust could be present. The episode of dust formation started at about 530 days and proceeded rapidly, so that by 600 days 45% of the bolometric luminosity was being emitted in the IR; by 775 days, 86% of the bolometric luminosity was being reradiated by the dust. Measurements of the bolometric luminosity of SN1987A from
DEFF Research Database (Denmark)
Bahr, Patrick; Hutton, Graham
2015-01-01
In this article, we present a new approach to the problem of calculating compilers. In particular, we develop a simple but general technique that allows us to derive correct compilers from high-level semantics by systematic calculation, with all details of the implementation of the compilers...... falling naturally out of the calculation process. Our approach is based upon the use of standard equational reasoning techniques, and has been applied to calculate compilers for a wide range of language features and their combination, including arithmetic expressions, exceptions, state, various forms...
Radar Signature Calculation Facility
Federal Laboratory Consortium — FUNCTION: The calculation, analysis, and visualization of the spatially extended radar signatures of complex objects such as ships in a sea multipath environment and...
Electrical installation calculations basic
Kitcher, Christopher
2013-01-01
All the essential calculations required for basic electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practice. A step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3Fo
Electrical installation calculations advanced
Kitcher, Christopher
2013-01-01
All the essential calculations required for advanced electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practiceA step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3For apprentices and electrical installatio
Electronics Environmental Benefits Calculator
U.S. Environmental Protection Agency — The Electronics Environmental Benefits Calculator (EEBC) was developed to assist organizations in estimating the environmental benefits of greening their purchase,...
Pflaumann, Uwe; Duprat, Josette; Pujol, Claude; Labeyrie, Laurent D.
1996-02-01
leave the system.) (Paper 95PA01743,SIMMAX: A modern analog technique to deduce Atlantic sea surfacetemperatures from planktonic foraminifera in deep-sea sediments, UwePflaumann, Josette Duprat, Claude Pujol, and Laurent D. Labeyrie).Diskette may be ordered from American Geophysical Union, 2000Florida Avenue, N.W., Washington, DC 20009; Payment mustaccompany order.
Doubre, Cécile; Déprez, Aline; Masson, Frédéric; Socquet, Anne; Lewi, Elias; Grandin, Raphaël; Nercessian, Alexandre; Ulrich, Patrice; De Chabalier, Jean-Bernard; Saad, Ibrahim; Abayazid, Ahmadine; Peltzer, Gilles; Delorme, Arthur; Calais, Eric; Wright, Tim
2017-02-01
Kinematics of divergent boundaries and Rift-Rift-Rift junctions are classically studied using long-term geodetic observations. Since significant magma-related displacements are expected, short-term deformation provides important constraints on the crustal mechanisms involved both in active rifting and in transfer of extensional deformation between spreading axes. Using InSAR and GPS data, we analyse the surface deformation in the whole Central Afar region in detail, focusing on both the extensional deformation across the Quaternary magmato-tectonic rift segments, and on the zones of deformation transfer between active segments and spreading axes. The largest deformation occurs across the two recently activated Asal-Ghoubbet (AG) and Manda Hararo-Dabbahu (MH-D) magmato-tectonic segments with very high strain rates, whereas the other Quaternary active segments do not concentrate any large strain, suggesting that these rifts are either sealed during interdyking periods or not mature enough to remain a plate boundary. Outside of these segments, the GPS horizontal velocity field shows a regular gradient following a clockwise rotation of the displacements from the Southeast to the East of Afar, with respect to Nubia. Very few shallow creeping structures can be identified as well in the InSAR data. However, using these data together with the strain rate tensor and the rotations rates deduced from GPS baselines, the present-day strain field over Central Afar is consistent with the main tectonic structures, and therefore with the long-term deformation. We investigate the current kinematics of the triple junction included in our GPS data set by building simple block models. The deformation in Central Afar can be described by adding a central microblock evolving separately from the three surrounding plates. In this model, the northern block boundary corresponds to a deep EW-trending trans-tensional dislocation, locked from the surface to 10-13 km and joining at depth the
First-forbidden transitions and stellar $\\beta$-decay rates of Zn and Ge isotopes
Nabi, Jameel-Un; Stoica, Sabin; Iftikhar, Zafar
2016-01-01
First-forbidden (FF) charge-changing transitions become relatively important for nuclei as their proton number increases. This is because the strength of allowed Gamow-Teller (GT) transitions decreases with increasing Z. The FF transitions play an important role in reducing the half-lives as against those calculated from taking the GT transitions alone into account. In this paper we calculate allowed GT as well as $0^{+} \\rightarrow 0^{-}$ and $0^{+} \\rightarrow 2^{-}$ transitions for neutron-rich Zn and Ge isotopes. Two different pn-QRPA models were used with a schematic separable interaction to calculate GT and FF transitions. Half-lives calculated after inclusion of FF transitions were in excellent agreement with the experimental data. Our calculations were also compared to previous QRPA calculations and were found to be in better agreement with measured data. Stellar $\\beta$-decay rates were calculated for these nuclei including allowed GT and unique FF transitions for astrophysical applications. $^{86,88...
Calculators and Polynomial Evaluation.
Weaver, J. F.
The intent of this paper is to suggest and illustrate how electronic hand-held calculators, especially non-programmable ones with limited data-storage capacity, can be used to advantage by students in one particular aspect of work with polynomial functions. The basic mathematical background upon which calculator application is built is summarized.…
Energy Technology Data Exchange (ETDEWEB)
Martoff, C.J.
1980-11-01
Photon spectra for 50 < E/sub ..gamma../ < 135 MeV have been measured from the radiative capture of stopped negative pions by the nuclides /sup 13/C, /sup 19/F, /sup 20/Ne, and /sup 90/Zr. The e/sup +/e/sup -/ pair spectrometer system used has resolution 850 keV fwhm and photon detection efficiency 5 x 10/sup -6/. The total radiative capture branching ratios measured are /sup 13/C (1.66 +- 0.25)%, /sup 19/F (2.40 +- 0.48)%, /sup 20/Ne (1.60 +- 0.24)%, and /sup 90/Zr (2.1 +- 0.5)%. The partial radiative capture branching ratios to four bound states and two resonances in /sup 20/F, and two bound states and three resonances in /sup 13/B have also been measured. The branching ratio for /sup 13/C(..pi../sup -/,..gamma..)/sup 13/B g.s. is (6.1 +- 1.2) x 10/sup -4/. Comparison of this result with the beta decay rate of /sup 13/B shows that (84 +- 16)% of the pion capture amplitude is accounted for by the Gamow-Teller matrix element. Further analysis suggests that much of the remaining strength is E2. The measured branching ratios to resonant states in /sup 13/C(..pi../sup -/,..gamma..)/sup 13/B are shown to be in agreement with detailed shell model calculations. The total single-particle strength in these transitions is shown to be approximately half as large as that of the T = 3/2 part of the E1 photoresonance (the Giant Dipole Resonance) in /sup 13/C. The branching ratio for /sup 20/Ne(..pi../sup -/,..gamma..)/sup 20/F (T = 1, J/sup ..pi../ = 1/sup +/, E/sub x/ = 1.06 MeV) is 0.91 +- 0.52).10/sup -4/. Comparison with the electroexcitation of the analog giant M1 state in /sup 20/Ne (11.24 MeV) shows that the M1 transition amplitude is less than (46 +- 14)% Gamow-Teller. This result is in agreement with detailed shell model calculations of the M1 transition. The photon spectrum for radiative pion capture from flight (reaction /sup 12/C(..pi../sup +/ T = 44 MeV, ..gamma.. at 90/sup 0/)) has been measured. 13 figures, 12 tables.
Energy Technology Data Exchange (ETDEWEB)
Nabi, Jameel-Un; Iftikhar, Zafar [GIK Institute of Engineering Sciences and Technology, Faculty of Engineering Sciences, Khyber Pakhtunkhwa (Pakistan); Cakmak, Necla [Karabuek University, Department of Physics, Karabuek (Turkey)
2016-01-15
First-forbidden (FF) transitions can play an important role in decreasing the calculated half-lives specially in environments where allowed Gamow-Teller (GT) transitions are unfavored. Of special mention is the case of neutron-rich nuclei where, due to phase-space amplification, FF transitions are much favored. We calculate the allowed GT transitions in various pn-QRPA models for even-even neutron-rich isotopes of nickel. Here we also study the effect of deformation on the calculated GT strengths. The FF transitions for even-even neutron-rich isotopes of nickel are calculated assuming the nuclei to be spherical. Later we take into account deformation of nuclei and calculate GT + unique FF transitions, stellar β -decay rates, energy rate of β -delayed neutrons and probability of β -delayed neutron emissions. The calculated half-lives are in excellent agreement with measured ones and might contribute in speeding-up of the r-matter flow. (orig.)
Nabi, Jameel-Un; Iftikhar, Zafar
2016-01-01
First-forbidden (FF) transitions can play an important role in decreasing the calculated half-lives specially in environments where allowed Gamow-Teller (GT) transitions are unfavored. Of special mention is the case of neutron-rich nuclei where, due to phase-space amplification, FF transitions are much favored. We calculate the allowed GT transitions in various pn-QRPA models for even-even neutron-rich isotopes of nickel. Here we also study the effect of deformation on the calculated GT strengths. The FF transitions for even-even neutron-rich isotopes of nickel are calculated assuming the nuclei to be spherical. Later we take into account deformation of nuclei and calculate GT + unique FF transitions, stellar $\\beta$-decay rates, energy rate of $\\beta$-delayed neutrons and probability of $\\beta$-delayed neutron emissions. The calculated half-lives are in excellent agreement with measured ones and might contribute in speeding-up of the $r$-matter flow.
Directory of Open Access Journals (Sweden)
D. Schaub
2006-01-01
Full Text Available Nitrogen dioxide (NO2 vertical tropospheric column densities (VTCs retrieved from the Global Ozone Monitoring Experiment (GOME are compared to coincident ground-based tropospheric NO2 columns. The ground-based columns are deduced from in situ measurements at different altitudes in the Alps for 1997 to June 2003, yielding a unique long-term comparison of GOME NO2 VTC data retrieved by a collaboration of KNMI (Royal Netherlands Meteorological Institute and BIRA/IASB (Belgian Institute for Space Aeronomy with independently derived tropospheric NO2 profiles. A first comparison relates the GOME retrieved tropospheric columns to the tropospheric columns obtained by integrating the ground-based NO2 measurements. For a second comparison, the tropospheric profiles constructed from the ground-based measurements are first multiplied with the averaging kernel (AK of the GOME retrieval. The second approach makes the comparison independent from the a priori NO2 profile used in the GOME retrieval. This allows splitting the total difference between the column data sets into two contributions: one that is due to differences between the a priori and the ground-based NO2 profile shapes, and another that can be attributed to uncertainties in both the remaining retrieval parameters (such as, e.g., surface albedo or aerosol concentration and the ground-based in situ NO2 profiles. For anticyclonic clear sky conditions the comparison indicates a good agreement between the columns (n=157, R=0.70/0.74 for the first/second comparison approach, respectively. The mean relative difference (with respect to the ground-based columns is −7% with a standard deviation of 40% and GOME on average slightly underestimating the ground-based columns. Both data sets show a similar seasonal behaviour with a distinct maximum of spring NO2 VTCs. Further analysis indicates small GOME columns being systematically smaller than the ground-based ones. The influence of different shapes in the a
Horvath, Monica M; Rusincovitch, Shelley A; Brinson, Stephanie; Shang, Howard C; Evans, Steve; Ferranti, Jeffrey M
2014-12-01
Data generated in the care of patients are widely used to support clinical research and quality improvement, which has hastened the development of self-service query tools. User interface design for such tools, execution of query activity, and underlying application architecture have not been widely reported, and existing tools reflect a wide heterogeneity of methods and technical frameworks. We describe the design, application architecture, and use of a self-service model for enterprise data delivery within Duke Medicine. Our query platform, the Duke Enterprise Data Unified Content Explorer (DEDUCE), supports enhanced data exploration, cohort identification, and data extraction from our enterprise data warehouse (EDW) using a series of modular environments that interact with a central keystone module, Cohort Manager (CM). A data-driven application architecture is implemented through three components: an application data dictionary, the concept of "smart dimensions", and dynamically-generated user interfaces. DEDUCE CM allows flexible hierarchies of EDW queries within a grid-like workspace. A cohort "join" functionality allows switching between filters based on criteria occurring within or across patient encounters. To date, 674 users have been trained and activated in DEDUCE, and logon activity shows a steady increase, with variability between months. A comparison of filter conditions and export criteria shows that these activities have different patterns of usage across subject areas. Organizations with sophisticated EDWs may find that users benefit from development of advanced query functionality, complimentary to the user interfaces and infrastructure used in other well-published models. Driven by its EDW context, the DEDUCE application architecture was also designed to be responsive to source data and to allow modification through alterations in metadata rather than programming, allowing an agile response to source system changes. Copyright © 2014 Elsevier
Horvath, Monica M.; Rusincovitch, Shelley A.; Brinson, Stephanie; Shang, Howard C.; Evans, Steve; Ferranti, Jeffrey M.
2015-01-01
Purpose Data generated in the care of patients are widely used to support clinical research and quality improvement, which has hastened the development of self-service query tools. User interface design for such tools, execution of query activity, and underlying application architecture have not been widely reported, and existing tools reflect a wide heterogeneity of methods and technical frameworks. We describe the design, application architecture, and use of a self-service model for enterprise data delivery within Duke Medicine. Methods Our query platform, the Duke Enterprise Data Unified Content Explorer (DEDUCE), supports enhanced data exploration, cohort identification, and data extraction from our enterprise data warehouse (EDW) using a series of modular environments that interact with a central keystone module, Cohort Manager (CM). A data-driven application architecture is implemented through three components: an application data dictionary, the concept of “smart dimensions”, and dynamically-generated user interfaces. Results DEDUCE CM allows flexible hierarchies of EDW queries within a grid-like workspace. A cohort “join” functionality allows switching between filters based on criteria occurring within or across patient encounters. To date, 674 users have been trained and activated in DEDUCE, and logon activity shows a steady increase, with variability between months. A comparison of filter conditions and export criteria shows that these activities have different patterns of usage across subject areas. Conclusions Organizations with sophisticated EDWs may find that users benefit from development of advanced query functionality, complimentary to the user interfaces and infrastructure used in other well-published models. Driven by its EDW context, the DEDUCE application architecture was also designed to be responsive to source data and to allow modification through alterations in metadata rather than programming, allowing an agile response to source
Interval arithmetic in calculations
Bairbekova, Gaziza; Mazakov, Talgat; Djomartova, Sholpan; Nugmanova, Salima
2016-10-01
Interval arithmetic is the mathematical structure, which for real intervals defines operations analogous to ordinary arithmetic ones. This field of mathematics is also called interval analysis or interval calculations. The given math model is convenient for investigating various applied objects: the quantities, the approximate values of which are known; the quantities obtained during calculations, the values of which are not exact because of rounding errors; random quantities. As a whole, the idea of interval calculations is the use of intervals as basic data objects. In this paper, we considered the definition of interval mathematics, investigated its properties, proved a theorem, and showed the efficiency of the new interval arithmetic. Besides, we briefly reviewed the works devoted to interval analysis and observed basic tendencies of development of integral analysis and interval calculations.
Unit Cost Compendium Calculations
U.S. Environmental Protection Agency — The Unit Cost Compendium (UCC) Calculations raw data set was designed to provide for greater accuracy and consistency in the use of unit costs across the USEPA...
EFFECTIVE DISCHARGE CALCULATION GUIDE
Institute of Scientific and Technical Information of China (English)
D.S.BIEDENHARN; C.R.THORNE; P.J.SOAR; R.D.HEY; C.C.WATSON
2001-01-01
This paper presents a procedure for calculating the effective discharge for rivers with alluvial channels.An alluvial river adjusts the bankfull shape and dimensions of its channel to the wide range of flows that mobilize the boundary sediments. It has been shown that time-averaged river morphology is adjusted to the flow that, over a prolonged period, transports most sediment. This is termed the effective discharge.The effective discharge may be calculated provided that the necessary data are available or can be synthesized. The procedure for effective discharge calculation presented here is designed to have general applicability, have the capability to be applied consistently, and represent the effects of physical processes responsible for determining the channel, dimensions. An example of the calculations necessary and applications of the effective discharge concept are presented.
DEFF Research Database (Denmark)
Frederiksen, Morten
2014-01-01
Williamson’s characterisation of calculativeness as inimical to trust contradicts most sociological trust research. However, a similar argument is found within trust phenomenology. This paper re-investigates Williamson’s argument from the perspective of Løgstrup’s phenomenological theory of trust....... Contrary to Williamson, however, Løgstrup’s contention is that trust, not calculativeness, is the default attitude and only when suspicion is awoken does trust falter. The paper argues that while Williamson’s distinction between calculativeness and trust is supported by phenomenology, the analysis needs...... to take actual subjective experience into consideration. It points out that, first, Løgstrup places trust alongside calculativeness as a different mode of engaging in social interaction, rather conceiving of trust as a state or the outcome of a decision-making process. Secondly, the analysis must take...
Magnetic Field Grid Calculator
National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Properties Calculator will computes the estimated values of Earth's magnetic field(declination, inclination, vertical component, northerly...
Scientific calculating peripheral
Energy Technology Data Exchange (ETDEWEB)
Ethridge, C.D.; Nickell, J.D. Jr.; Hanna, W.H.
1979-09-01
A scientific calculating peripheral for small intelligent data acquisition and instrumentation systems and for distributed-task processing systems is established with a number-oriented microprocessor controlled by a single component universal peripheral interface microcontroller. A MOS/LSI number-oriented microprocessor provides the scientific calculating capability with Reverse Polish Notation data format. Master processor task definition storage, input data sequencing, computation processing, result reporting, and interface protocol is managed by a single component universal peripheral interface microcontroller.
Current interruption transients calculation
Peelo, David F
2014-01-01
Provides an original, detailed and practical description of current interruption transients, origins, and the circuits involved, and how they can be calculated Current Interruption Transients Calculationis a comprehensive resource for the understanding, calculation and analysis of the transient recovery voltages (TRVs) and related re-ignition or re-striking transients associated with fault current interruption and the switching of inductive and capacitive load currents in circuits. This book provides an original, detailed and practical description of current interruption transients, origins,
Shielding calculations for SSC
Energy Technology Data Exchange (ETDEWEB)
Van Ginneken, A.
1990-03-01
Monte Carlo calculations of hadron and muon shielding for SSC are reviewed with emphasis on their application to radiation safety and environmental protection. Models and algorithms for simulation of hadronic and electromagnetic showers, and for production and transport of muons in the TeV regime are briefly discussed. Capabilities and limitations of these calculations are described and illustrated with a few examples. 12 refs., 3 figs.
Geometric unsharpness calculations
Energy Technology Data Exchange (ETDEWEB)
Anderson, D.J. [International Training and Education Group (INTEG), Oakville, Ontario (Canada)
2008-07-15
The majority of radiographers' geometric unsharpness calculations are normally performed with a mathematical formula. However, a majority of codes and standards refer to the use of a nomograph for this calculation. Upon first review, the use of a nomograph appears more complicated but with a few minutes of study and practice it can be just as effective. A review of this article should provide enlightenment. (author)
Source and replica calculations
Energy Technology Data Exchange (ETDEWEB)
Whalen, P.P.
1994-02-01
The starting point of the Hiroshima-Nagasaki Dose Reevaluation Program is the energy and directional distributions of the prompt neutron and gamma-ray radiation emitted from the exploding bombs. A brief introduction to the neutron source calculations is presented. The development of our current understanding of the source problem is outlined. It is recommended that adjoint calculations be used to modify source spectra to resolve the neutron discrepancy problem.
INVAP's Nuclear Calculation System
Ignacio Mochi
2011-01-01
Since its origins in 1976, INVAP has been on continuous development of the calculation system used for design and optimization of nuclear reactors. The calculation codes have been polished and enhanced with new capabilities as they were needed or useful for the new challenges that the market imposed. The actual state of the code packages enables INVAP to design nuclear installations with complex geometries using a set of easy-to-use input files that minimize user errors due to confusion or mi...
Energy Technology Data Exchange (ETDEWEB)
Dagbjartsson, S. J.; Appelhans, T. D.; Quapp, W. J.
1979-01-01
The relationship of axial gas flow and fuel temperature measurements to fuel cracking and relocation occurring during the first month of irradiation of light water reactor fuel rods is discussed. Two types of fuel rod axial gas flow tests were used to determine the effective hydraulic diameter and its change during the ramping operations. Fuel centerline and off-center measurements are compared with the results of the gas flow analysis and pretest FRAP calculations.
Billingsley, F. P., II; Krauss, M.
1974-01-01
Using the optimized valence configurations (OVC) multiconfiguration self-consistent-field (MCSCF) method, the dipole moment function for the ground state of CO in the vicinity of the equilibrium internuclear distance has been calculated. The OVC MCSCF calculation results are compared with existing Hartree-Fock and configuration interaction treatments of this molecule at single points and also the dipole moment function deduced from experimental infrared intensities. A general prescription for constructing OVC wavefunctions for diatomic molecules is also presented.
Institute of Scientific and Technical Information of China (English)
杨忠志; 沈尔忠
1996-01-01
On the basis of a more precise expression of the atomic effective electronegativity deduced from the density functional theory and electronegativity equalization principle, a new scheme for calculating the group electronegativity and the atomic charges in a group is proposed and programed, and various parameters of electronegativity and hardness are given for some common atoms. Through calculation, analysis and comparison of more than one hundred groups, it is shown that the results from this scheme are reasonable and may be extended.
Calculation formula for apparent electrical resistivity of high porosity metal materials
Institute of Scientific and Technical Information of China (English)
刘培生; 付超; 李铁藩
1999-01-01
A geometrical model has been established based on the structure feature of high porosity metal materials,the mathematical relationship between electrical resistivity and porosity for high porosity materials with even structure has then been deduced conveniently, and the formula for calculating the electrical resistivity of high porosity materials through porosity, which is easy to know, has been acquired further. Besides, the theoretical formula was verified to coincide with the test results well by the application taking nickel foam as an example.
Jaye, M; de la Salle, H; Schamber, F; Balland, A; Kohli, V; Findeli, A; Tolstoshev, P; Lecocq, J P
1983-04-25
A unique 52mer oligonucleotide deduced from the amino acid sequence of bovine Factor IX was synthesized and used as a probe to screen a human liver cDNA bank. The Factor IX clone isolated shows 5 differences in nucleotide and deduced amino acid sequence as compared to a previously isolated clone. In addition, precisely one codon has been deleted.Images
Calculations of proton chemical shifts in olefins and aromatics
Escrihuela, M C
2000-01-01
induced reagents on alpha,beta unsaturated ketones has also been investigated in order to deduce molecular structures and to obtain the assignment of the spectra of these molecules. A semi-empirical calculation of the partial atomic charges in organic compounds based on molecular dipole moments (CHARGE3) was developed into a model capable of predicting proton chemical shifts in a wide variety of organic compounds to a reasonable degree of accuracy. The model has been modified to include condensed aromatic hydrocarbons and substituted benzenes, alkenes, halo-monosubstituted benzenes and halo-alkenes. Within the aromatic compounds the influence of the pi electron densities and the ring current have been investigated, along with the alpha, beta and gamma effects. The model gives the first accurate calculation of the proton chemical shifts of condensed aromatic compounds and the proton substituent chemical shifts (SCS) in the benzene ring. For the data set of 55 proton chemical shifts spanning 3 ppm the rms error...
Neyrinck, Marleen M; Vrielink, Hans
2015-02-01
It's important to work smoothly with your apheresis equipment when you are an apheresis nurse. Attention should be paid to your donor/patient and the product you're collecting. It gives additional value to your work when you are able to calculate the efficiency of your procedures. You must be capable to obtain an optimal product without putting your donor/patient at risk. Not only the total blood volume (TBV) of the donor/patient plays an important role, but also specific blood values influence the apheresis procedure. Therefore, not all donors/patients should be addressed in the same way. Calculation of TBV, extracorporeal volume, and total plasma volume is needed. Many issues determine your procedure time. By knowing the collection efficiency (CE) of your apheresis machine, you can calculate the number of blood volumes to be processed to obtain specific results. You can calculate whether you need one procedure to obtain specific results or more. It's not always needed to process 3× the TBV. In this way, it can be avoided that the donor/patient is needless long connected to the apheresis device. By calculating the CE of each device, you can also compare the various devices for quality control reasons, but also nurses/operators.
Competition between α and β decays for heavy deformed neutron-deficient Pa, U, Np, and Pu isotopes
Ni, Dongdong; Ren, Zhongzhou
2017-01-01
The competition between α and β decays is investigated for neutron-deficient Pa, U, Np, and Pu isotopes. β+/electron-capture (EC) decay rates are calculated within the deformed quasiparticle random-phase approximation with realistic nucleon-nucleon (N N ) interactions. Contributions from allowed Gamow-Teller and Fermi transitions as well as first-forbidden transitions are considered. α -decay calculations are performed within the generalized density-dependent cluster model. Effects of differences between neutron and proton distributions and nuclear deformation are taken into account. In the calculations, Reid-93 N N interactions are used for β+/EC decays, while Michigan three-range Yukawa effective interactions, based on the G -matrix elements of Reid N N potentials, are used for α decay. The calculated β -decay half-lives show good agreement with the experimental data over a range of magnitude from 102 to 105 s. The resulting total half-lives including α and β contributions are found to be in good agreement with the experimental data, together with the α /β -decay branching ratios.
Rahman, Muneeb-Ur
2016-01-01
Charge-changing transitions, commonly referred to as Gamow-Teller (GT) transitions, and electron capture/$\\beta^{+}$-decay strengths for pf-shell nuclei with $T_{z} = - 2$ at proton drip-line have been calculated using the proton-neutron quasi-particle random phase approximation (pn-QRPA) model. The total GT$_{+}$ strength values and electron capture/$\\beta^{+}$-decay rates are needed for the study of the late stages of the stellar evolution. The pn-QRPA theory is used for a microscopic calculation of GT strength distribution functions and associated stellar electron capture/$\\beta^{+}$-decay rates of proton-rich pf-shell nuclei with $T_{z} = - 2$ in the mass range 46 $\\leq$ A $\\leq$ 56 at proton drip-line. Standard quenching factor of 0.74, usually implemented in the shell model calculation, has been incorporated for the comparison with experimental data (wherever available). The calculated GT strength of the two proton-rich nuclei, $^{52}$Ni and $^{56}$Zn are compared with experimental data of corresponding...
OFTIFEL PERSONALIZED NUTRITIONAL CALCULATOR
Directory of Open Access Journals (Sweden)
Malte BETHKE
2016-11-01
Full Text Available A food calculator for elderly people was elaborated by Centiv GmbH, an active partner in the European FP7 OPTIFEL Project, based on the functional requirement specifications and the existing recommendations for daily allowances across Europe, data which were synthetized and used to give aims in amounts per portion. The OPTIFEL Personalised Nutritional Calculator is the only available online tool which allows to determine on a personalised level the required nutrients for elderly people (65+. It has been developed mainly to support nursing homes providing best possible (personalised nutrient enriched food to their patients. The European FP7 OPTIFEL project “Optimised Food Products for Elderly Populations” aims to develop innovative products based on vegetables and fruits for elderly populations to increase length of independence. The OPTIFEL Personalised Nutritional Calculator is recommended to be used by nursing homes.
INVAP's Nuclear Calculation System
Directory of Open Access Journals (Sweden)
Ignacio Mochi
2011-01-01
Full Text Available Since its origins in 1976, INVAP has been on continuous development of the calculation system used for design and optimization of nuclear reactors. The calculation codes have been polished and enhanced with new capabilities as they were needed or useful for the new challenges that the market imposed. The actual state of the code packages enables INVAP to design nuclear installations with complex geometries using a set of easy-to-use input files that minimize user errors due to confusion or misinterpretation. A set of intuitive graphic postprocessors have also been developed providing a fast and complete visualization tool for the parameters obtained in the calculations. The capabilities and general characteristics of this deterministic software package are presented throughout the paper including several examples of its recent application.
Salgado, C A; Salgado, Carlos A.; Wiedemann, Urs Achim
2003-01-01
We calculate the probability (``quenching weight'') that a hard parton radiates an additional energy fraction due to scattering in spatially extended QCD matter. This study is based on an exact treatment of finite in-medium path length, it includes the case of a dynamically expanding medium, and it extends to the angular dependence of the medium-induced gluon radiation pattern. All calculations are done in the multiple soft scattering approximation (Baier-Dokshitzer-Mueller-Peign\\'e-Schiff--Zakharov ``BDMPS-Z''-formalism) and in the single hard scattering approximation (N=1 opacity approximation). By comparison, we establish a simple relation between transport coefficient, Debye screening mass and opacity, for which both approximations lead to comparable results. Together with this paper, a CPU-inexpensive numerical subroutine for calculating quenching weights is provided electronically. To illustrate its applications, we discuss the suppression of hadronic transverse momentum spectra in nucleus-nucleus colli...
Spin Resonance Strength Calculations
Courant, E. D.
2009-08-01
In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.
Spin resonance strength calculations
Energy Technology Data Exchange (ETDEWEB)
Courant,E.D.
2008-10-06
In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
Compared with ellipse cavity, the spoke cavity has many advantages, especially for the low and medium beam energy. It will be used in the superconductor accelerator popular in the future. Based on the spoke cavity, we design and calculate an accelerator
Haida Numbers and Calculation.
Cogo, Robert
Experienced traders in furs, blankets, and other goods, the Haidas of the 1700's had a well-developed decimal system for counting and calculating. Their units of linear measure included the foot, yard, and fathom, or six feet. This booklet lists the numbers from 1 to 20 in English and Haida; explains the Haida use of ten, hundred, and thousand…
Curvature calculations with GEOCALC
Energy Technology Data Exchange (ETDEWEB)
Moussiaux, A.; Tombal, P.
1987-04-01
A new method for calculating the curvature tensor has been recently proposed by D. Hestenes. This method is a particular application of geometric calculus, which has been implemented in an algebraic programming language on the form of a package called GEOCALC. They show how to apply this package to the Schwarzchild case and they discuss the different results.
Daylight calculations in practice
DEFF Research Database (Denmark)
Iversen, Anne; Roy, Nicolas; Hvass, Mette;
programs can give different results. This can be due to restrictions in the program itself and/or be due to the skills of the persons setting up the models. This is crucial as daylight calculations are used to document that the demands and recommendations to daylight levels outlined by building authorities...
Kolev, D.; Ernst, J.
1998-03-01
A model interpretation of isomeric ratios for 0954-3899/24/3/010/img7 and 0954-3899/24/3/010/img8 produced in the reactions 0954-3899/24/3/010/img9, 0954-3899/24/3/010/img10, 0954-3899/24/3/010/img11, 0954-3899/24/3/010/img12, 0954-3899/24/3/010/img13 and 0954-3899/24/3/010/img14 is presented. The experimental isomeric ratios were obtained using bremsstrahlung radiation with end-point energies of 18 and 43 MeV. The calculations were performed by means of the well known code STAPRE and the new code COMPLET. Angular-momentum removal in pre-equilibrium emission was found to be much more important for the observed isomeric ratios than subsequent compound-nucleus evaporation.
Inelastic neutrino scattering off hot nuclei in supernova environments
Dzhioev, Alan A.; Vdovin, A. I.; Wambach, J.; Ponomarev, V. Yu.
2014-03-01
We study inelastic neutrino scattering off hot nuclei for temperatures relevant under supernova conditions. The method we use is based on the quasiparticle random phase approximation extended to finite temperatures within the thermo-field dynamics. The method allows a transparent treatment of upward and downward transitions in hot nuclei, avoiding the application of Brink's hypothesis. For the sample nuclei 56Fe and 82Ge we perform a detailed analysis of thermal effects on the strength distributions of allowed Gamow-Teller (GT) transitions which dominate the scattering process at low neutrino energies. For 56Fe and 82Ge the finite temperature cross sections are calculated by taking into account the contribution of allowed and forbidden transitions. The observed enhancement of the cross section at low neutrino energies is explained by considering thermal effects on the GT strength. For 56Fe we compare the calculated cross sections to those obtained earlier from a hybrid approach that combines large-scale shell-model and RPA calculations.
Rahman, Muneeb-Ur
2014-01-01
The Gamow-Teller (GT) transitions within massive stars play sumptuous role in the dynamics of core collapse supernovae. GT strength distributions and electron capture rates have been calculated for odd-A nucleus $^{59}$Co within the proton-neutron quasiparticles random phase approximation (pn-QRPA) formalism. The pn-QRPA results are compared with other model calculations and (n, p) reaction experiment carried out at TRIUMF charge-exchange facility. The pn-QRPA calculated a total $B(GT_{+})$ strength of 3.3 for $^{59}$Co to be compared with the shell model value of 2.5 and the 1.9 $\\pm$ 0.1 in the (n, p) charge-exchange reaction. Aufderheide et. al. \\cite{Aufderheide93} extracted total strength equaling 2.4 $\\pm$ 0.3. The placement of GT centroid at 5.6 MeV by the pn-QRPA model is in reasonable agreement with the shell model centroid at 5.1 MeV whereas the measured GT centroid was placed at 4.4 $\\pm$ 0.3 MeV in the (n, p) experiment. Fuller, Fowler and Newman (FFN) \\cite{FFN80, FFN82, FFN82b}, placed the GT ce...
Nabi, Jameel-Un
2016-01-01
We investigate even-even nuclei in the $A\\sim70$ mass region within the framework of the proton-neutron quasi-particle random phase approximation (\\mbox{pn-QRPA}) and the interacting boson model-1 (\\mbox{IBM-1}). Our work includes calculation of the energy spectra and the potential energy surfaces $V(\\beta,\\gamma)$ of Zn, Ge, Se, Kr and Sr nuclei with the same proton and neutron number, $N = Z$. The parametrization of the \\mbox{IBM-1} Hamiltonian was performed for the calculation of the energy levels in the ground state bands. Geometric shape of the nuclei was predicted by plotting the potential energy surfaces $V(\\beta,\\gamma)$ obtained from the \\mbox{IBM-1} Hamiltonian in the classical limit. The \\mbox{pn-QRPA} model was later used to compute half-lives of the neutron-deficient nuclei which were found to be in very good agreement with the measured ones. The \\mbox{pn-QRPA} model was also used to calculate the Gamow-Teller strength distributions and was found to be in decent agreement with the measured data. ...
Zander, R.; Rinsland, C. P.; Russell, J. M., III; Farmer, C. B.; Norton, R. H.
1988-01-01
This paper presents the results on the volume mixing ratio profiles of carbonyl sulfide and hydrogen cyanide, deduced from the spectroscopic analysis of IR solar absorption spectra obtained in the occultation mode with the Atmospheric Trace Molecule Spectroscopy (ATMOS) instrument during its mission aboard Spacelab 3. A comparison of the ATMOS measurements for both northern and southern latitudes with previous field investigations at low midlatitudes shows a relatively good agreement. Southern Hemisphere volume mixing ratio profiles for both molecules were obtained for the first time, as were the profiles for the Northern Hemisphere covering the upper troposphere and the lower stratosphere simultaneously.
Radioprotection calculations for MEGAPIE.
Zanini, L
2005-01-01
The MEGAwatt PIlot Experiment (MEGAPIE) liquid lead-bismuth spallation neutron source will commence operation in 2006 at the SINQ facility of the Paul Scherrer Institut. Such an innovative system presents radioprotection concerns peculiar to a liquid spallation target. Several radioprotection issues have been addressed and studied by means of the Monte Carlo transport code, FLUKA. The dose rates in the room above the target, where personnel access may be needed at times, from the activated lead-bismuth and from the volatile species produced were calculated. Results indicate that the dose rate level is of the order of 40 mSv h(-1) 2 h after shutdown, but it can be reduced below the mSv h(-1) level with slight modifications to the shielding. Neutron spectra and dose rates from neutron transport, of interest for possible damage to radiation sensitive components, have also been calculated.
PIC: Protein Interactions Calculator.
Tina, K G; Bhadra, R; Srinivasan, N
2007-07-01
Interactions within a protein structure and interactions between proteins in an assembly are essential considerations in understanding molecular basis of stability and functions of proteins and their complexes. There are several weak and strong interactions that render stability to a protein structure or an assembly. Protein Interactions Calculator (PIC) is a server which, given the coordinate set of 3D structure of a protein or an assembly, computes various interactions such as disulphide bonds, interactions between hydrophobic residues, ionic interactions, hydrogen bonds, aromatic-aromatic interactions, aromatic-sulphur interactions and cation-pi interactions within a protein or between proteins in a complex. Interactions are calculated on the basis of standard, published criteria. The identified interactions between residues can be visualized using a RasMol and Jmol interface. The advantage with PIC server is the easy availability of inter-residue interaction calculations in a single site. It also determines the accessible surface area and residue-depth, which is the distance of a residue from the surface of the protein. User can also recognize specific kind of interactions, such as apolar-apolar residue interactions or ionic interactions, that are formed between buried or exposed residues or near the surface or deep inside.
Cohen, Barbara A.; Coker, R. F.
2009-01-01
The South Pole-Aitken (SPA) basin is an important target for absolute age-dating. Vertical and lateral impact mixing ensures that regolith within SPA will contain rock fragments from SPA itself, local impact craters, and faraway giant basins. About 20% of the regolith at any given site is foreign [1, 2], but much of this material will be cold ejecta, not impact melt. We calculated the fraction of contributed impact melt using scaling laws to estimate the amount and provenance of impact melt, demonstrating that SPA melt is the dominant impact melt rock (>70%) likely to be present. We also constructed a statistical model to illustrate how many randomly-selected impact-melt fragments would need to be dated, and with what accuracy, to confidently reproduce the impact history of a site. A detailed impact history becomes recognizable after a few hundred to a thousand randomly-selected marbles, however, it will be useful to have more information (e.g. compositional, mineralogical, remote sensing) to group fragments. These exercises show that SPA melt has a high probability of being present in a scoop sample and that dating of a few hundred to a thousand impact-melt fragments will yield the impact history of the SPA basin.
Zech, R.; Kull, Ch.; Kubik, P. W.; Veit, H.
2007-10-01
Surface exposure dating (SED) is an innovative tool already being widely applied for moraine dating and for Late Quaternary glacier and climate reconstruction. Here we present exposure ages of 28 boulders from the Cordillera Real and the Cordillera Cochabamba, Bolivia. Our results indicate that the local Last Glacial Maximum (LGM) in the Eastern Cordilleras occurred at ~22-25 ka and was thus synchronous to the global temperature minimum. We were also able to date several Late Glacial moraines to ~11-13 ka, which likely document lower temperatures and increased precipitation ("Coipasa" humid phase). Additionally, we recognize the existence of older Late Glacial moraines re-calculated to ~15 ka from published cosmogenic nuclide data. Those may coincide with the cold Heinrich 1 event in the North Atlantic region and the pronounced "Tauca" humid phase. We conclude that (i) exposure ages in the tropical Andes may have been overestimated so far due to methodological uncertainties, and (ii) although precipitation plays an important role for glacier mass balances in the tropical Andes, it becomes the dominant forcing for glaciation only in the drier and thus more precipitation-sensitive regions farther west and south.
Directory of Open Access Journals (Sweden)
H. Veit
2007-10-01
Full Text Available Surface exposure dating (SED is an innovative tool already being widely applied for moraine dating and for Late Quaternary glacier and climate reconstruction. Here we present exposure ages of 28 boulders from the Cordillera Real and the Cordillera Cochabamba, Bolivia. Our results indicate that the local Last Glacial Maximum (LGM in the Eastern Cordilleras occurred at ~22–25 ka and was thus synchronous to the global temperature minimum. We were also able to date several Late Glacial moraines to ~11–13 ka, which likely document lower temperatures and increased precipitation ("Coipasa" humid phase. Additionally, we recognize the existence of older Late Glacial moraines re-calculated to ~15 ka from published cosmogenic nuclide data. Those may coincide with the cold Heinrich 1 event in the North Atlantic region and the pronounced "Tauca" humid phase. We conclude that (i exposure ages in the tropical Andes may have been overestimated so far due to methodological uncertainties, and (ii although precipitation plays an important role for glacier mass balances in the tropical Andes, it becomes the dominant forcing for glaciation only in the drier and thus more precipitation-sensitive regions farther west and south.
Al Farrah, Nawal; Van Camp, Marc; Walraevens, Kristine
2013-09-01
The hydraulic characterisation of aquifer systems is important for the development of exploitation scenarios and management strategies. Especially in lithologically heterogeneous aquifers, local scale variations in transmissivity (T) may not be neglected. Field scale transmissivity values are usually derived from pumping tests, but in most cases their number and availability is rather limited. Therefore T values are often estimated from specific well capacities (SC) which can easily be measured in exploitation wells based on static and dynamic water levels. Empirical relations allow T to be calculated from SC values using a power law relation of the form T = A * SCN. In this paper this relation is investigated for three aquifers in north-west Lybia, using the results from step-drawdown tests which allow determination of well efficiencies, which can be incorporated into the regression analysis. The obtained fitting coefficients of the power law relations were compared with published values from other studies. Both parameters of the power law relation (scale factor and power coefficient) seem to be highly correlated following an exponential relationship (R2 = 0.89), reducing the T-SC relation to a single parameter equation, which is mainly related to lithology.
Resources calculation of cobalt-rich crusts with the grid subdivision and integral method
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
On the basis of three geological models and several orebody boundaries, a method of grid subdivision and integral has been proposed to calculate and evaluate the resources of cobalt-rich crusts on the seamounts in the central Pacific Ocean. The formulas of this method are deduced and the interface of program module is designed. The method is carried out in the software "Auto mapping system of submarine topography and geomorphology MBChart". This method and program will possibly become a potential tool to calculate the resources of seamounts and determine the target diggings for China's next Five-year Plan.
New reaction rates for improved primordial D/H calculation and the cosmic evolution of deuterium
Coc, Alain; Uzan, Jean-Philippe; Vangioni, Elisabeth; Descouvemont, Pierre; Illiadis, Christian; Longland, Richard
2015-01-01
Primordial or big bang nucleosynthesis (BBN) is one of the three historical strong evidences for the big bang model. Standard BBN is now a parameter free theory, since the baryonic density of the Universe has been deduced with an unprecedented precision from observations of the anisotropies of the cosmic microwave background (CMB) radiation. There is a good agreement between the primordial abundances of 4He, D, 3He and 7Li deduced from observations and from primordial nucleosynthesis calculations. However, the 7Li calculated abundance is significantly higher than the one deduced from spectroscopic observations and remains an open problem. In addition, recent deuterium observations have drastically reduced the uncertainty on D/H, to reach a value of 1.6%. It needs to be matched by BBN predictions whose precision is now limited by thermonuclear reaction rate uncertainties. This is especially important as many attempts to reconcile Li observations with models lead to an increased D prediction. Here, we re-evalua...
New reaction rates for improved primordial D /H calculation and the cosmic evolution of deuterium
Coc, Alain; Petitjean, Patrick; Uzan, Jean-Philippe; Vangioni, Elisabeth; Descouvemont, Pierre; Iliadis, Christian; Longland, Richard
2015-12-01
Primordial or big bang nucleosynthesis (BBN) is one of the three historically strong evidences for the big bang model. Standard BBN is now a parameter-free theory, since the baryonic density of the Universe has been deduced with an unprecedented precision from observations of the anisotropies of the cosmic microwave background radiation. There is a good agreement between the primordial abundances of 4He, D, 3He, and 7Li deduced from observations and from primordial nucleosynthesis calculations. However, the 7Li calculated abundance is significantly higher than the one deduced from spectroscopic observations and remains an open problem. In addition, recent deuterium observations have drastically reduced the uncertainty on D /H , to reach a value of 1.6%. It needs to be matched by BBN predictions whose precision is now limited by thermonuclear reaction rate uncertainties. This is especially important as many attempts to reconcile Li observations with models lead to an increased D prediction. Here, we reevaluate the d (p ,γ )3He, d (d ,n ) 3H3, and d (d ,p ) 3H reaction rates that govern deuterium destruction, incorporating new experimental data and carefully accounting for systematic uncertainties. Contrary to previous evaluations, we use theoretical ab initio models for the energy dependence of the S factors. As a result, these rates increase at BBN temperatures, leading to a reduced value of D /H =(2.45 ±0.10 )×10-5 (2 σ ), in agreement with observations.
We propose to use the new ISOLDE decay station and the neutron detector VANDLE to measure the $\\beta$-delayed neutron emission of N=82-84 $^{130-132}$Cd isotopes. The large delayed neutron emission probability observed in a previous ISOLDE measurement is indicative of the Gamow-Teller transitions due to the decay of deep core neutrons. Core Gamow-Teller decay has been experimentally proven in the $^{78}$Ni region for the N>50 nuclei using the VANDLE array. The spectroscopic measurement of delayed neutron emission along the cadmium isotopic chain will allow us to track the evolution of the single particle states and the shell gap.
First Results From GRIFFIN: Half-Lives of Neutron Rich 128-130Cd
Dunlop, Ryan; Griffin Collaboration
2016-09-01
Half-lives of N = 82 nuclei below doubly-magic 132Sn are key input parameters for any astrophysical r-process scenario and play an important role in the formation and shape of the second r-process abundance peak. Shell-model calculations for neutron-rich nuclei near the N = 82 neutron shell closure that are not yet experimentally accessible have been performed by adjusting the quenching of the Gamow-Teller (GT) operator to reproduce the 130Cd half-life. The calculated half-lives of other nuclei in the region are known to be systematically too long. Recently, a shorter half-life for 130Cd was measured by the EURICA collaboration that resolves this discrepancy by scaling the GT quenching by a constant factor for all of the nuclei in the region. Distinguishing between these discrepant half-life measurements for 130Cd is thus of critical importance. We have measured the half-lives of 128-130Cd using the high-efficiency GRIFFIN γ-ray spectrometer at TRIUMF, which improves the precision of the 128,129Cd half-lives, and confirms the shorter half-life of 130Cd recently reported by the EURICA collaboration. Details of the GRIFFIN experiments will be presented and the implications of the resulting half-lives discussed.
Progress in research, April 1, 1992--March 31, 1993, Texas A and M University Cyclotron Institute
Energy Technology Data Exchange (ETDEWEB)
NONE
1993-07-01
This Institute annual report for the period 1 April 1992--31 March 1993 covers a period which has seen the initial runs of three new spectrometers which constitute a major portion of the new detection capabilities developed for this facility. These devices are the Proton Spectrometer (PSP), the Mass Achromat Recoil Mass Spectrometer (MARS), and the Multipole dipole Multipole (MDM) Particle Spectrometer. These devices are now available to pursue the studies of Gamow Teller states, reactions of astrophysical interest, and giant resonance studies for which they were constructed, as well as for other experiments. A beam analysis system which will deliver high resolution beams to the MDM spectrometer is currently under construction. With the completion of these spectrometer projects, the facility emphasis is now focused on the development of the full capabilities of the K500 cyclotron and on the research program. During the report period, the ECR-K500 cyclotron combination operated 5,849 hours. Theoretical work reported in this document ranges from nuclear structure calculations using the IBM-2 model to calculations of kaon production and the in-medium properties of the rho and phi mesons, the latter as a probe of the QCD phase transition. Nuclear dynamics and exotic shapes and fragmentation modes of hot nuclei are also addressed. In atomic physics, new measurements of x-ray emission from highly ionized ions, of molecular dissociation and of surface interactions are reported.
Annakkage, T; Winfield, J S; Berg, G P A; Brown, J A; Crawley, G; Danczyk, S; Fujiwara, M; Mercer, D J; Pham, K; Roberts, D A; Stasko, J T; Yoo, G H
1999-01-01
The ( sup 7 Li, sup 7 Be) and ( sup 7 Li, sup 7 Be gamma) reactions have been studied at bombarding energies of 50 A MeV on targets of sup 6 Li, sup 1 sup 2 C, sup 9 sup 0 Zr, sup 1 sup 2 sup 0 Sn, sup 2 sup 0 sup 8 Pb, and polystyrene. The detection of Doppler-shifted gamma-rays from excited sup 7 Be permits the identification of the spinflip and non-spinflip characteristics. Transitions to over 20 discrete states and resonances have been observed. Angular distributions for sup 6 Li and sup 1 sup 2 C are well described by microscopic one-step distorted-waves calculations with shell-model transition amplitudes. The transitions to the ground states of sup 6 He and sup 1 sup 2 C exhibit significant Gamow-Teller strength, but approx 7% and approx 17%, respectively, of the calculated cross sections at theta approx 0 deg. arise from the tensor interaction. A broad resonance at approx 5.6 MeV in the halo nucleus sup 6 He with J suppi = (2 sup + , 1 sup - , 0 sup +) seems to correspond to a structure predicted at th...
Spin-isospin transitions in chromium isotopes within the quasiparticle random phase approximation
Cakmak, Sadiye; Babacan, Tahsin; Maras, Ismail
2016-01-01
Beta decay and electron capture on isotopes of chromium are advocated to play a key role in the stellar evolution process. In this paper we endeavor to study charge-changing transitions for 24 isotopes of chromium ($^{42-65}$Cr). These include neutron-rich and neutron-deficient isotopes of chromium. Three different models from the QRPA genre, namely the pn-QRPA, the Pyatov method (PM) and the Schematic model (SM), were selected to calculate and study the Gamow-Teller (GT) transitions in chromium isotopes. The SM was employed separately in the particle-particle ($pp$) and $pp$ + particle-hole ($ph$) channels. To study the effect of deformation, the SM was first used assuming the nuclei to be spherical and later to be deformed. The PM was used both in $pp$ and $pp$ + $ph$ channels but only for the case of spherical nuclei. The pn-QRPA calculation was done by considering both $pp$ and $ph$ forces and taking deformation of nucleus into consideration. A recent study proved this version of pn-QRPA to be the best fo...
β decay of Si,4038 (Tz=+5 ,+6 ) to low-lying core excited states in odd-odd P,4038 isotopes
Tripathi, Vandana; Lubna, R. S.; Abromeit, B.; Crawford, H. L.; Liddick, S. N.; Utsuno, Y.; Bender, P. C.; Crider, B. P.; Dungan, R.; Fallon, P.; Kravvaris, K.; Larson, N.; Macchiavelli, A. O.; Otsuka, T.; Prokop, C. J.; Richard, A. L.; Shimizu, N.; Tabor, S. L.; Volya, A.; Yoshida, S.
2017-02-01
Low-lying excited states in P,4038 have been identified in the β decay of Tz=+5 ,+6 , Si,4038. Based on the allowed nature of the Gamow-Teller (GT) decay observed, these states are assigned spin and parity of 1+ and are core-excited 1p1h intruder states with a parity opposite to the ground state. The occurrence of intruder states at low energies highlights the importance of pairing and quadrupole correlation energies in lowering the intruder states despite the N =20 shell gap. Configuration interaction shell model calculations with the state-of-art SDPF-MU effective interaction were performed to understand the structure of these 1p1h states in the even-A phosphorus isotopes. States in 40P with N =25 were found to have very complex configurations involving all the f p orbitals leading to deformed states as seen in neutron-rich nuclei with N ≈28 . The calculated GT matrix elements for the β decay highlight the dominance of the decay of the core neutrons rather than the valence neutrons.
Nuclear inputs of key iron isotopes for core-collapse modeling and simulation
Nabi, Jameel-Un
2014-01-01
From the modeling and simulation results of presupernova evolution of massive stars, it was found that isotopes of iron, $^{54,55,56}$Fe, play a significant role inside the stellar cores, primarily decreasing the electron-to-baryon ratio ($Y_{e}$) mainly via electron capture processes thereby reducing the pressure support. The neutrinos produced, as a result of these capture processes, are transparent to the stellar matter and assist in cooling the core thereby reducing the entropy. The structure of the presupernova star is altered both by the changes in $Y_{e}$ and the entropy of the core material. Here we present the microscopic calculation of Gamow-Teller strength distributions for isotopes of iron. The calculation is also compared with other theoretical models and experimental data. Presented also are stellar electron capture rates and associated neutrino cooling rates, due to isotopes of iron, in a form suitable for simulation and modeling codes. It is hoped that the nuclear inputs presented here should ...
Directory of Open Access Journals (Sweden)
M. Scherer
2008-03-01
Full Text Available This paper presents an updated trend analysis of water vapour in the lower midlatitude stratosphere from the Boulder balloon-borne NOAA frostpoint hygrometer measurements and from the Halogen Occulation Experiment (HALOE. Two corrections for instrumental bias are applied to homogenise the frostpoint data series, and a quality assessment of all soundings after 1991 is presented. Linear trend estimates based on the corrected data for the period 1980–2000 are up to 40% lower than previously reported. Vertically resolved trends and variability are calculated with a multi regression analysis including the quasi-biennal oscillation and equivalent latitude as explanatory variables. In the range of 380 to 640 K potential temperature (≈14 to 25 km, the frostpoint data from 1981 to 2006 show positive linear trends between 0.3±0.3 and 0.7±0.1%/yr. The same dataset shows trends between −0.2±0.3 and 1.0±0.3%/yr for the period 1992 to 2005. HALOE data over the same time period suggest negative trends ranging from −1.1±0.2 to −0.1±0.1%/yr. In the lower stratosphere, a rapid drop of water vapour is observed in 2000/2001 with little change since. At higher altitudes, the transition is more gradual, with slowly decreasing concentrations between 2001 and 2007. This pattern is consistent with a change induced by a drop of water concentrations at entry into the stratosphere. Previously noted differences in trends and variability between frostpoint and HALOE remain for the homogenised data. Due to uncertainties in reanalysis temperatures and stratospheric transport combined with uncertainties in observations, no quantitative inference about changes of water entering the stratosphere in the tropics could be made with the mid latitude measurements analysed here.
She, Yawen; Fu, Guangyu; Wang, Zhuohua; Liu, Tai; Xu, Changyi; Jin, Honglin
2016-10-01
The current work describes the combined data of three field campaigns, spanning 2009-2013. Their joint gravity and GPS observations thoroughly cover the sites of lithospheric flexure between the Sichuan Basin and the Eastern Tibetan Plateau. The study area's free-air gravity anomalies (FGAs) are updated by using a remove-and-restore algorithm which merges EGM2008 data with in situ observations. These new FGAs show pairs of positive and negative anomalies along the eastern edges of the Tibetan Plateau. The FGAs are used to calculate effective elastic thickness ( T e) and load ratios ( F) of the lithosphere. Admittance analysis indicates the T e of Longmen Shan (LMS) to be 6 km, and profile analysis indicates that the T e of the Sichuan Basin excesses 30 km. The load ratio ( F 1 = 1) confirms that the lithospheric flexure of the LMS area can be attributed solely to the surface load of the crust. [Figure not available: see fulltext. Caption: The current work describes the combined data of three field campaigns, spanning 2009-2013. Their joint gravity and GPS observations thoroughly cover the sites of lithospheric flexure between the Sichuan Basin and the Eastern Tibetan Plateau. The study area's free-air gravity anomalies (FGAs) are updated by using a remove-and-restore algorithm which merges EGM2008 data with in situ observations. With the new FGAs data, the lithospheric strength of the study area is studied by the authors, and they also give a combined model to illustrate the uplift mechanism of this area.
Breuer, Sonja; Kilian, Rolf; Baeza, Oscar; Lamy, Frank; Arz, Helge
2013-04-01
Holocene denudation rates and their regional variations in the superhumid and temperate climate of the southernmost Patagonian Andes are poorly surveyed. Therefore we have investigated denudation in five small lake catchments (0.11-1.62 km2) across a precipitation gradient from 600 to > 9000 mm yr- 1 in southernmost Chile at 53°S. Variations in denudation rates can be defined most precisely by using small catchments and short time spans (Holocene) thus can be related to variable bedrock types, vegetation cover, elevation, and climate. Minimum physical denudation rates were determined from sediment budgets based on sediment echosounder data and physical properties of sediment cores. The Holocene denudation rates vary from 0.08 mm kyr- 1 in the highly elevated, bare granitic rock catchments to 9.01 mm kyr- 1 in the low and vegetated catchments with a basement of sedimentary rocks. These values are comparable with those from similar areas in Norway, Sweden, and NW Iceland. The high annual precipitation in the study area has only a minor effect on denudation. Enhanced geomorphic activity during paraglacial conditions caused a faster denudation after the glacier retreat until either the clastic, glacial detritus was removed or the catchment was covered with vegetation. Chemical comparisons between basement rocks and lake sediments indicate a pronounced chemical denudation in catchments with peaty soils and low soil water pH values of 3 to 5. The Holocene surface lowering rates are on average 200 fold lower than Cenozoic surface lowering rates calculated from fission-track data for the southern Andes. This discrepancy can be explained by significantly higher erosion rates during glacial periods.
Fang, J.
2016-12-01
In order to investigate the lithospheric structure of the South China Sea and adjacent regions and it's lateral crustal density variations, we using a two-step approach. First the crustal and lithospheric mantle structure is calculated from the geoid height and elevation data combined with thermal analysis further constrained by seismic data. We then compute the 3D gravity effect of the resulting lithospheric structure to separate the measured Bouguer anomaly into its regional and local components. Our results show that for the majority of the study area the crustal thickness does correlate with the regional topography pattern. Moho depth varies from ˜10 km at the Central basin to ˜35 km at the continental shelf and slope zones. The lithosphere is thinner beneath the Central basin (˜70 km) and thicker underneath the continental shelf and slope zones (˜100 km). The residual gravity anomaly, obtained by subtraction of the regional components to the measured field, is analyzed in terms of the dominating upper crustal structures. Central basins and areas with high velocity layer are characterized by positive values (20 100 mGal), whereas the negative values are related to the Trough and Trench, such as Nansha Trough and Manila Trench and shallow basement depths(-100 -20 mGal). The transform boundary of continental-oceanic is consistent with the residual gravity anomaly gradient zone and is proposed accordingly. The variation of Moho and the residual gravity anomaly exists between the conjugate margins which demonstrated the asymmetric crustal extension of the South China Sea margin.
Ikehara, Kenji
2016-01-26
It is no doubt quite difficult to solve the riddle of the origin of life. So, firstly, I would like to point out the kinds of obstacles there are in solving this riddle and how we should tackle these difficult problems, reviewing the studies that have been conducted so far. After that, I will propose that the consecutive evolutionary steps in a timeline can be rationally deduced by using a common event as a juncture, which is obtained by two counter-directional approaches: one is the bottom-up approach through which many researchers have studied the origin of life, and the other is the top-down approach, through which I established the [GADV]-protein world hypothesis or GADV hypothesis on the origin of life starting from a study on the formation of entirely new genes in extant microorganisms. Last, I will describe the probable evolutionary process from the formation of Earth to the emergence of life, which was deduced by using a common event-the establishment of the first genetic code encoding [GADV]-amino acids-as a juncture for the results obtained from the two approaches.
Directory of Open Access Journals (Sweden)
Kunio Kawamura
2016-08-01
Full Text Available RNA played a central role in the emergence of the first life-like system on primitive Earth since RNA molecules contain both genetic information and catalytic activity. However, there are several drawbacks regarding the RNA world hypothesis. Here, I briefly discuss the feasibility of the RNA world hypothesis to deduce the RNA functions that are essential for forming a life-like system. At the same time, I have conducted a conceptual analysis of the characteristics of biosystems as a useful approach to deduce a realistic life-like system in relation to the definition of life. For instance, an RNA-based life-like system should possess enough stability to resist environmental perturbations, by developing a cell-like compartment, for instance. Here, a conceptual viewpoint is summarized to provide a realistic life-like system that is compatible with the primitive Earth environment and the capabilities of RNA molecules. According to the empirical and conceptual analysis, I propose the hypothesis that the first life-like system could have initiated from only two genes.
Kawamura, Kunio
2016-08-02
RNA played a central role in the emergence of the first life-like system on primitive Earth since RNA molecules contain both genetic information and catalytic activity. However, there are several drawbacks regarding the RNA world hypothesis. Here, I briefly discuss the feasibility of the RNA world hypothesis to deduce the RNA functions that are essential for forming a life-like system. At the same time, I have conducted a conceptual analysis of the characteristics of biosystems as a useful approach to deduce a realistic life-like system in relation to the definition of life. For instance, an RNA-based life-like system should possess enough stability to resist environmental perturbations, by developing a cell-like compartment, for instance. Here, a conceptual viewpoint is summarized to provide a realistic life-like system that is compatible with the primitive Earth environment and the capabilities of RNA molecules. According to the empirical and conceptual analysis, I propose the hypothesis that the first life-like system could have initiated from only two genes.
Directory of Open Access Journals (Sweden)
Kenji Ikehara
2016-01-01
Full Text Available It is no doubt quite difficult to solve the riddle of the origin of life. So, firstly, I would like to point out the kinds of obstacles there are in solving this riddle and how we should tackle these difficult problems, reviewing the studies that have been conducted so far. After that, I will propose that the consecutive evolutionary steps in a timeline can be rationally deduced by using a common event as a juncture, which is obtained by two counter-directional approaches: one is the bottom-up approach through which many researchers have studied the origin of life, and the other is the top-down approach, through which I established the [GADV]-protein world hypothesis or GADV hypothesis on the origin of life starting from a study on the formation of entirely new genes in extant microorganisms. Last, I will describe the probable evolutionary process from the formation of Earth to the emergence of life, which was deduced by using a common event—the establishment of the first genetic code encoding [GADV]-amino acids—as a juncture for the results obtained from the two approaches.
Zero Temperature Hope Calculations
Energy Technology Data Exchange (ETDEWEB)
Rozsnyai, B F
2002-07-26
The primary purpose of the HOPE code is to calculate opacities over a wide temperature and density range. It can also produce equation of state (EOS) data. Since the experimental data at the high temperature region are scarce, comparisons of predictions with the ample zero temperature data provide a valuable physics check of the code. In this report we show a selected few examples across the periodic table. Below we give a brief general information about the physics of the HOPE code. The HOPE code is an ''average atom'' (AA) Dirac-Slater self-consistent code. The AA label in the case of finite temperature means that the one-electron levels are populated according to the Fermi statistics, at zero temperature it means that the ''aufbau'' principle works, i.e. no a priory electronic configuration is set, although it can be done. As such, it is a one-particle model (any Hartree-Fock model is a one particle model). The code is an ''ion-sphere'' model, meaning that the atom under investigation is neutral within the ion-sphere radius. Furthermore, the boundary conditions for the bound states are also set at the ion-sphere radius, which distinguishes the code from the INFERNO, OPAL and STA codes. Once the self-consistent AA state is obtained, the code proceeds to generate many-electron configurations and proceeds to calculate photoabsorption in the ''detailed configuration accounting'' (DCA) scheme. However, this last feature is meaningless at zero temperature. There is one important feature in the HOPE code which should be noted; any self-consistent model is self-consistent in the space of the occupied orbitals. The unoccupied orbitals, where electrons are lifted via photoexcitation, are unphysical. The rigorous way to deal with that problem is to carry out complete self-consistent calculations both in the initial and final states connecting photoexcitations, an enormous computational task
Linewidth calculations and simulations
Strandberg, Ingrid
2016-01-01
We are currently developing a new technique to further enhance the sensitivity of collinear laser spectroscopy in order to study the most exotic nuclides available at radioactive ion beam facilities, such as ISOLDE at CERN. The overall goal is to evaluate the feasibility of the new method. This report will focus on the determination of the expected linewidth (hence resolution) of this approach. Different effects which could lead to a broadening of the linewidth, e.g. the ions' energy spread and their trajectories inside the trap, are studied with theoretical calculations as well as simulations.
Angarita, Fernando A.; University Health Network; Acuña, Sergio A.; Mount Sinai Hospital; Jimenez, Carolina; University of Toronto; Garay, Javier; Pontificia Universidad Javeriana; Gömez, David; University of Toronto; Domínguez, Luis Carlos; Pontificia Universidad Javeriana
2010-01-01
Acute calculous cholecystitis is the most important cause of cholecystectomies worldwide. We review the physiopathology of the inflammatory process in this organ secondary to biliary tract obstruction, as well as its clinical manifestations, workup, and the treatment it requires. La colecistitis calculosa aguda es la causa más importante de colecistectomías en el mundo. En esta revisión de tema se resume la fisiopatología del proceso inflamatorio de la vesículabiliar secundaria a la obstru...
Calculations in furnace technology
Davies, Clive; Hopkins, DW; Owen, WS
2013-01-01
Calculations in Furnace Technology presents the theoretical and practical aspects of furnace technology. This book provides information pertinent to the development, application, and efficiency of furnace technology. Organized into eight chapters, this book begins with an overview of the exothermic reactions that occur when carbon, hydrogen, and sulfur are burned to release the energy available in the fuel. This text then evaluates the efficiencies to measure the quantity of fuel used, of flue gases leaving the plant, of air entering, and the heat lost to the surroundings. Other chapters consi
Kocsis, László; Ounis, Anouar; Chaabani, Fredj; Salah, Neili Mohamed
2013-06-01
Fossil shark teeth and coprolites from three major phosphorite occurrences in the Gafsa Basin (southwestern Tunisia) were investigated for their geochemical compositions to improve local stratigraphy and to better assess paleoenvironmental conditions. 87Sr/86Sr isotope ratios of shark teeth from the Early Maastrichtian El Haria Formation and from the Early Eocene Métlaoui s.s. Formation yielded Sr isotope ages of 68 ± 1 and 47.9 ± 1.3 Ma, respectively, which accord with the expected stratigraphic positions of these sediments. Conversely, shark teeth from the Paleocene-Eocene Chouabine Formation have large variation in Sr isotope ratios even within individual layers. After statistical treatment and then elimination of certain outlier samples, three age-models are proposed and discussed. The most reasonable solution includes three subsequent Sr ages of 61.8 ± 2.2 Ma, 57.2 ± 1.8 and 54.6 ± 1.6 for layer IX, layers VIII-V and layers IV-0, respectively. Three scenarios are discussed for explanation of the presence of the outliers: (1) diagenesis, (2) re-working and (3) locally controlled seawater Sr isotope ratio. The most plausible account for the higher 87Sr/86Sr ratios relative to the global ocean in some fossils is enhanced intrabasinal re-working due to low sea level. Conversely, the sample with lower 87Sr/86Sr than the global seawater may link to diagenesis or to seawater influenced by weathering of Late Cretaceous marine carbonates, which latter is supported by model calculation as well. The ɛNd values of these fossils are very similar to those reported for Paleogene and Late Cretaceous Tethyan seawater and are compatible with the above interpretations. The relatively low oxygen isotope values in shark teeth from the topmost phosphate bed of the Chouabine Formation, together with the Sr isotope results, point toward recovering better connections with the open sea. These δ18O data reflect elevated ambient temperature, which may link to the Early Eocene
OECD Maximum Residue Limit Calculator
With the goal of harmonizing the calculation of maximum residue limits (MRLs) across the Organisation for Economic Cooperation and Development, the OECD has developed an MRL Calculator. View the calculator.
Bhatnagar, Shalabh
2017-01-01
Sound is an emerging source of renewable energy but it has some limitations. The main limitation is, the amount of energy that can be extracted from sound is very less and that is because of the velocity of the sound. The velocity of sound changes as per medium. If we could increase the velocity of the sound in a medium we would be probably able to extract more amount of energy from sound and will be able to transfer it at a higher rate. To increase the velocity of sound we should know the speed of sound. If we go by the theory of classic mechanics speed is the distance travelled by a particle divided by time whereas velocity is the displacement of particle divided by time. The speed of sound in dry air at 20 °C (68 °F) is considered to be 343.2 meters per second and it won't be wrong in saying that 342.2 meters is the velocity of sound not the speed as it's the displacement of the sound not the total distance sound wave covered. Sound travels in the form of mechanical wave, so while calculating the speed of sound the whole path of wave should be considered not just the distance traveled by sound. In this paper I would like to focus on calculating the actual speed of sound wave which can help us to extract more energy and make sound travel with faster velocity.
Multilayer optical calculations
Byrnes, Steven J
2016-01-01
When light hits a multilayer planar stack, it is reflected, refracted, and absorbed in a way that can be derived from the Fresnel equations. The analysis is treated in many textbooks, and implemented in many software programs, but certain aspects of it are difficult to find explicitly and consistently worked out in the literature. Here, we derive the formulas underlying the transfer-matrix method of calculating the optical properties of these stacks, including oblique-angle incidence, absorption-vs-position profiles, and ellipsometry parameters. We discuss and explain some strange consequences of the formulas in the situation where the incident and/or final (semi-infinite) medium are absorptive, such as calculating $T>1$ in the absence of gain. We also discuss some implementation details like complex-plane branch cuts. Finally, we derive modified formulas for including one or more "incoherent" layers, i.e. very thick layers in which interference can be neglected. This document was written in conjunction with ...
Algebraic calculation of stroboscopic maps of ordinary, nonlinear differential equations
Energy Technology Data Exchange (ETDEWEB)
Wackerbauer, R. (Max-Planck-Institut fuer Extraterrestrische Physik, Garching (Germany)); Huebler, A. (Illinois Univ., Urbana, IL (United States). Center for Complex Systems Research); Mayer-Kress, G. (Los Alamos National Lab., NM (United States) California Univ., Santa Cruz, CA (United States). Dept. of Mathematics)
1991-07-25
The relation between the parameters of a differential equation and corresponding discrete maps are becoming increasingly important in the study of nonlinear dynamical systems. Maps are well adopted for numerical computation and several universal properties of them are known. Therefore some perturbation methods have been proposed to deduce them for physical systems, which can be modeled by an ordinary differential equation (ODE) with a small nonlinearity. A new iterative, rigorous algebraic method for the calculation of the coefficients of a Taylor expansion of a stroboscopic map from ODE's with not necessarily small nonlinearities is presented. It is shown analytically that most of the coefficients are small for a small integration time and grow slowly in the course of time if the flow vector field of the ODE is polynomial and if the ODE has fixed point in the origin. Approximations of different orders respectively of the rest term are investigated for several nonlinear systems. 31 refs., 16 figs.
The calculation method of mixing volume in a products pipeline
Energy Technology Data Exchange (ETDEWEB)
Gong, Jing; Wang, Qim [China University of Petroleum, Beijing, (China); Wang, Weidongn [Sinopec South China Sales Company, (China); Guo, Yi [CNPC Oil and Gas pipeline control center, (China)
2010-07-01
This paper investigated calculation methods of mixing volume on a pipeline. A method of simulation was developed by combining the Austin-Palfrey empirical formula and field data. The field data were introduced to improve the accuracy of the Austin-Palfrey formula by including other factors such as the terrain, the structure of the pipeline, the characteristics of mixed oil products in pumping stations and the distribution of products along the pipeline. These other factors were collected from field data and analyzed statistically to deduce coefficients. The comparison with field results showed that the formula developed for contamination provided accurate values. The formula achieved more accurate results using the characteristics of the field pipeline. This formula could be used for field application.
Molecular Dynamics Calculations
1996-01-01
The development of thermodynamics and statistical mechanics is very important in the history of physics, and it underlines the difficulty in dealing with systems involving many bodies, even if those bodies are identical. Macroscopic systems of atoms typically contain so many particles that it would be virtually impossible to follow the behavior of all of the particles involved. Therefore, the behavior of a complete system can only be described or predicted in statistical ways. Under a grant to the NASA Lewis Research Center, scientists at the Case Western Reserve University have been examining the use of modern computing techniques that may be able to investigate and find the behavior of complete systems that have a large number of particles by tracking each particle individually. This is the study of molecular dynamics. In contrast to Monte Carlo techniques, which incorporate uncertainty from the outset, molecular dynamics calculations are fully deterministic. Although it is still impossible to track, even on high-speed computers, each particle in a system of a trillion trillion particles, it has been found that such systems can be well simulated by calculating the trajectories of a few thousand particles. Modern computers and efficient computing strategies have been used to calculate the behavior of a few physical systems and are now being employed to study important problems such as supersonic flows in the laboratory and in space. In particular, an animated video (available in mpeg format--4.4 MB) was produced by Dr. M.J. Woo, now a National Research Council fellow at Lewis, and the G-VIS laboratory at Lewis. This video shows the behavior of supersonic shocks produced by pistons in enclosed cylinders by following exactly the behavior of thousands of particles. The major assumptions made were that the particles involved were hard spheres and that all collisions with the walls and with other particles were fully elastic. The animated video was voted one of two
Ahrens, Thomas J.; Okeefe, J. D.; Smither, C.; Takata, T.
1991-01-01
In the course of carrying out finite difference calculations, it was discovered that for large craters, a previously unrecognized type of crater (diameter) growth occurred which was called lip wave propagation. This type of growth is illustrated for an impact of a 1000 km (2a) silicate bolide at 12 km/sec (U) onto a silicate half-space at earth gravity (1 g). The von Misses crustal strength is 2.4 kbar. The motion at the crater lip associated with this wave type phenomena is up, outward, and then down, similar to the particle motion of a surface wave. It is shown that the crater diameter has grown d/a of approximately 25 to d/a of approximately 4 via lip propagation from Ut/a = 5.56 to 17.0 during the time when rebound occurs. A new code is being used to study partitioning of energy and momentum and cratering efficiency with self gravity for finite-sized objects rather than the previously discussed planetary half-space problems. These are important and fundamental subjects which can be addressed with smoothed particle hydrodynamic (SPH) codes. The SPH method was used to model various problems in astrophysics and planetary physics. The initial work demonstrates that the energy budget for normal and oblique impacts are distinctly different than earlier calculations for silicate projectile impact on a silicate half space. Motivated by the first striking radar images of Venus obtained by Magellan, the effect of the atmosphere on impact cratering was studied. In order the further quantify the processes of meteor break-up and trajectory scattering upon break-up, the reentry physics of meteors striking Venus' atmosphere versus that of the Earth were studied.
Shell Model Description of the C14 Dating β Decay with Brown-Rho-Scaled NN Interactions
Holt, J. W.; Brown, G. E.; Kuo, T. T. S.; Holt, J. D.; Machleidt, R.
2008-02-01
We present shell model calculations for the beta decay of C14 to the N14 ground state, treating the states of the A=14 multiplet as two 0p holes in an O16 core. We employ low-momentum nucleon-nucleon (NN) interactions derived from the realistic Bonn-B potential and find that the Gamow-Teller (GT) matrix element is too large to describe the known lifetime. By using a modified version of this potential that incorporates the effects of Brown-Rho scaling medium modifications, we find that the GT matrix element vanishes for a nuclear density around 85% that of nuclear matter. We find that the splitting between the (Jπ,T)=(1+,0) and (Jπ,T)=(0+,1) states in N14 is improved using the medium-modified Bonn-B potential and that the transition strengths from excited states of C14 to the N14 ground state are compatible with recent experiments.
Robin, Caroline; Litvinova, Elena
2016-07-01
A new theoretical approach to spin-isospin excitations in open-shell nuclei is presented. The developed method is based on the relativistic meson-exchange nuclear Lagrangian of Quantum Hadrodynamics and extends the response theory for superfluid nuclear systems beyond relativistic quasiparticle random phase approximation in the proton-neutron channel (pn-RQRPA). The coupling between quasiparticle degrees of freedom and collective vibrations (phonons) introduces a time-dependent effective interaction, in addition to the exchange of pion and ρ -meson taken into account without retardation. The time-dependent contributions are treated in the resonant time-blocking approximation, in analogy to the previously developed relativistic quasiparticle time-blocking approximation (RQTBA) in the neutral (non-isospin-flip) channel. The new method is called proton-neutron RQTBA (pn-RQTBA) and is applied to the Gamow-Teller resonance in a chain of neutron-rich nickel isotopes 68-78Ni . A strong fragmentation of the resonance along with quenching of the strength, as compared to pn-RQRPA, is obtained. Based on the calculated strength distribution, beta-decay half-lives of the considered isotopes are computed and compared to pn-RQRPA half-lives and to experimental data. It is shown that a considerable improvement of the half-life description is obtained in pn-RQTBA because of the spreading effects, which bring the lifetimes to a very good quantitative agreement with data.
The proton-proton weak capture in chiral effective field theory
Marcucci, L E; Viviani, M
2013-01-01
The astrophysical S-factor for proton-proton weak capture is calculated in chiral effective field theory over the center-of-mass relative-energy range 0--100 keV. The chiral two-nucleon potential derived up to next-to-next-to-next-to leading order is augmented by the full electromagnetic interaction including, beyond Coulomb, two-photon and vacuum-polarization corrections. The low-energy constants (LEC's) entering the weak current operators are fixed so as to reproduce the A=3 binding energies and magnetic moments, and the Gamow-Teller matrix element in tritium beta decay. Contributions from S and P partial waves in the incoming two-proton channel are retained. The S-factor at zero energy is found to be S(0)=(4.030\\pm 0.006) x 10^{-23} MeV fm^2, with a P-wave contribution of 0.020 x 10^{-23} MeV fm^2. The theoretical uncertainty is due to the fitting procedure of the LEC's and to the cutoff dependence. It is shown that polynomial fits to parametrize the energy dependence of the S-factor are inherently unstabl...
Beta-delayed gamma decay of 26P: Possible evidence of a proton halo
Pérez-Loureiro, D; Bennett, M B; Liddick, S N; Bowe, A; Brown, B A; Chen, A A; Chipps, K A; Cooper, N; Irvine, D; McNeice, E; Montes, F; Naqvi, F; Ortez, R; Pain, S D; Pereira, J; Prokop, C J; Quaglia, J; Quinn, S J; Sakstrup, J; Santia, M; Schwartz, S B; Shanab, S; Simon, A; Spyrou, A; Thiagalingam, E
2016-01-01
Background: Measurements of $\\beta$ decay provide important nuclear structure information that can be used to probe isospin asymmetries and inform nuclear astrophysics studies. Purpose: To measure the $\\beta$-delayed $\\gamma$ decay of $^{26}$P and compare the results with previous experimental results and shell-model calculations. Method: A $^{26}$P fast beam produced using nuclear fragmentation was implanted into a planar germanium detector. Its $\\beta$-delayed $\\gamma$-ray emission was measured with an array of 16 high-purity germanium detectors. Positrons emitted in the decay were detected in coincidence to reduce the background. Results: The absolute intensities of $^{26}$P $\\beta$-delayed $\\gamma$-rays were determined. A total of six new $\\beta$-decay branches and 15 new $\\gamma$-ray lines have been observed for the first time in $^{26}$P $\\beta$-decay. A complete $\\beta$-decay scheme was built for the allowed transitions to bound excited states of $^{26}$Si. $ft$ values and Gamow-Teller strengths were a...
The Structure of the Heavy Calcium Isotopes and the Effective Interaction in the sd-fp Shell
Dorvaux, O; Nowacki, F; Courtin, S; Marechal, F; Siiskonen, T M; Perrot, F; Pietri, S B
2002-01-01
Nuclei with 40 $<$ A $<$ 56, near the stability line, are very well described in the frame of the shell model. However, when the number of neutrons increases, the situation becomes more complex which explains why the interaction can be found very dissimilar within different calculations. Heavy Ca isotopes, because of the simplicity of their wave-functions, correspond to the optimal choice to fix unambiguously the interaction in this mass region.\\\\ It is proposed to measure the $\\beta$-decay of $^{51, 52, 53}$K with the help of an utmost performing neutron (TONNERRE array) and $\\gamma$- (Miniball clusters) detection, allowing efficient coincidence measurements. This will allow the lowest lying Gamow-Teller states to be located in $^{51, 52, 53}$Ca, and the still unknown properties of natural parity states to be investigated. The awaited results should allow to settle the n-n interaction in the fp shell and the Gnp matrix accross the sd and fp shells, one step farther from stability, by comparison with fu...
Spin dipole and quadrupole resonances in sup 40 Ca
Energy Technology Data Exchange (ETDEWEB)
Baker, F.T.; Love, W.G. (The University of Georgia, Athens, GA (USA)); Bimbot, L. (The University of Paris, Orsay, (France)); Fergerson, R.W.; Glashausser, C.; Green, A. (Rutgers University, New Brunswick, NJ (USA)); Jones, K. (Los Alamos National Laboratory, Los Alamos, NM (USA)); Nanda, S. (Continuous Electron Beam Accelerator Facility, Newport News, VA (USA) The University of Georgia, Athens, GA (USA))
1989-11-01
Angular distributions of the double differential cross section {ital d}{sup 2}{sigma}/d{Omega} dE({sigma}) and the spin-flip probability {ital S}{sub {ital nn}} have been measured for inclusive proton inelastic scattering from {sup 40}Ca at 319 MeV. Excitation energies ({omega}) up to about 40 MeV have been investigated over the angular range from 3.5{degree} to 12{degree} in the laboratory (0.3 to 0.9 fm{sup {minus}1}). Here, multipole decompositions of angular distributions of {sigma}{ital S}{sub {ital nn}} for the {sup 40}Ca({ital {rvec p}},{ital {rvec p}} {prime}) reaction at 319 MeV have been performed in order to compare {Delta}{ital S}=1 strength observed with sum rules. In contrast to the well-known quenching of Gamow-Teller and {ital M}1 resonances, the spin-dipole resonance has a total measured strength which is larger than that predicted by the energy-weighted sum rule. The spin-dipole strength distribution supports asymmetric widths predicted by calculations including 2p-2h mixing. The spin-quadrupole resonance is observed near {omega}=35 MeV and its total strength for {omega}{lt}40 MeV estimated.
Tritium $\\beta$-decay in chiral effective field theory
Baroni, A; Kievsky, A; Marcucci, L E; Schiavilla, R; Viviani, M
2016-01-01
We evaluate the Fermi and Gamow-Teller (GT) matrix elements in tritium \\beta-decay by including in the charge-changing weak current the corrections up to one loop recently derived in nuclear chiral effective field theory (\\chi EFT). The trinucleon wave functions are obtained from hyperspherical-harmonics solutions of the Schrodinger equation with two- and three-nucleon potentials corresponding to either \\chi EFT (the N3LO/N2LO combination) or meson-exchange phenomenology (the AV18/UIX combination). We find that contributions due to loop corrections in the axial current are, in relative terms, as large as (and in some cases, dominate) those from one-pion exchange, which nominally occur at lower order in the power counting. We also provide values for the low-energy constants multiplying the contact axial current and three-nucleon potential, required to reproduce the experimental GT matrix element and trinucleon binding energies in the N3LO/N2LO and AV18/UIX calculations.
Chiral effective field theory predictions for muon capture on deuteron and $^3$He
Energy Technology Data Exchange (ETDEWEB)
Laura E. Marcucci, A. Kievsky, S. Rosati, R. Schiavilla, M. Viviani
2012-01-01
The muon-capture reactions {sup 2}H({mu}{sup -}, {nu}{sub {mu}})nn and {sup 3}He({mu}{sup -},{nu}{sub {mu}}){sup 3}H are studied with nuclear strong-interaction potentials and charge-changing weak currents, derived in chiral effective field theory. The low-energy constants (LEC's) c{sub D} and c{sub E}, present in the three-nucleon potential and (c{sub D}) axial-vector current, are constrained to reproduce the A=3 binding energies and the triton Gamow-Teller matrix element. The vector weak current is related to the isovector component of the electromagnetic current via the conserved-vector-current constraint, and the two LEC's entering the contact terms in the latter are constrained to reproduce the A=3 magnetic moments. The muon capture rates on deuteron and {sup 3}He are predicted to be 399 {+-} 3 sec{sup -1} and 1494 {+-} 21 sec{sup -1}, respectively, where the spread accounts for the cutoff sensitivity as well as uncertainties in the LEC's and electroweak radiative corrections. By comparing the calculated and precisely measured rates on {sup 3}He, a value for the induced pseudoscalar form factor is obtained in good agreement with the chiral perturbation theory prediction.
Isoscalar pairing correlation in $^{100}{\\rm Sn}+p+n$ system
Tanimura, Yusuke
2016-01-01
We discuss the isoscalar $T=0, S=1$ pairing correlation in the low-lying states of $^{102}{\\rm Sb}={}^{100}{\\rm Sn}+p+n$ nucleus. To this end, we employ ${\\rm core}+p+n$ three-body model with the model space constructed by self-consistent mean-field calculations. The model is developed with both non-relativistic and relativistic effective interactions, the latter of which are found to be more realistic for the present case due to the pseudo-spin symmetry. It turns out that the $(L,S,T)=(0,1,0)$ pairing scheme is strongly hindered in $^{102}$Sb with the relativistic model because of the near degeneracy of the $g_{7/2}$ and $d_{5/2}$ orbitals in the valence space. This pair-breaking effect is clearly seen in the charge-exchange Gamow-Teller-type transitions rather than in the binding energies of $T=0$ and $T=1$ states.
Decay spectroscopy of N < Z nuclei around 100Sn
Park, Joochun (Jason); Eurica Collaboration
2016-09-01
Many interesting topics in both nuclear structure and nuclear astrophysics converge on the doubly-magic nucleus 100Sn and nuclei in its vicinity. Among them are the boundaries of proton dripline, the effect of pn interaction in self-conjugate nuclei, and the decay properties required for rp -process calculations in nucleosynthesis models. Despite many studies, experimental knowledge of these nuclides has remained scarce due to low production cross sections and a lack of intense beams. However, record quantities of exotic N = Z isotopes around 100Sn were produced at RIKEN Radioactive Isotope Beam Factory, via fragmentation of a 124Xe beam on a thin 9Be target. Based on the obtained data, 89Rh and 93Ag have been confirmed to be proton unbound. Half-lives of isotopes near the proton dripline will be presented with improved precision compared to literature values. In addition, strategies to determine Qβ for ft values, and consequently the Fermi/Gamow-Teller transition strengths of these isotope decays will be discussed. Work supported by the Natural Sciences and Engineering Research Council of Canada and the National Research Council of Canada.
Low-spin structure of 51,35,86Br and 50,36,86Kr nuclei: The role of the g7 /2 neutron orbital
Urban, W.; Sieja, K.; Materna, T.; Czerwiński, M.; Rząca-Urban, T.; Blanc, A.; Jentschel, M.; Mutti, P.; Köster, U.; Soldner, T.; de France, G.; Simpson, G. S.; Ur, C. A.; Bernards, C.; Fransen, C.; Jolie, J.; Regis, J.-M.; Thomas, T.; Warr, N.
2016-10-01
Low-spin excited levels in 51,35,86Br and 50,36,86Kr, populated following β- decay and the neutron-induced fission of 235U, were measured using the Lohengrin fission-fragment separator and the EXILL array of Ge detectors at the PF1B cold-neutron facility of the Institute Laue-Langevin Grenoble. Improved populations of excited levels in 86Br remove inconsistencies existing in the literature on this nucleus. Directional-linear-polarization correlations, analyzed using newly developed formulas, as well as precise angular correlations allowed the unique 1- and 2- spin and parity assignments to the ground state of 86Br and the 4016.3-keV level in 86Kr, respectively. Based on these results we propose that the Gamow-Teller β- decays of 86Se and 86Br involve the ν g7 /2→π g9 /2 transition in addition to the ν p3 /2→π p3 /2 transition proposed earlier. In 86Kr we have identified 11+, 23+, and 31+ levels, analogous to the mixed-symmetry states in 94Mo, which in 86Kr are from proton excitations, only. Large-scale, shell-model calculations with refined interactions reproduce well excitations in 86Br and 86Kr and support our interpretations.
Dutton, Andrew S; Suhrada, Christopher P; Miranda, Katrina M; Wink, David A; Fukuto, Jon M; Houk, K N
2006-03-20
Isopropylamine diazeniumdiolate, IPA/NO, the product of the reaction of isopropylamine and nitric oxide, NO, decomposes in a pH-dependent manner to afford nitroxyl, HNO, in the pH range of 13 to above 5, and NO below pH 7. Theoretical studies using B3LYP/6-311+G(d) density functional theory, the polarizable continuum and conductor-like polarizable continuum solvation models, and the high-accuracy CBS-QB3 method on the simplified model compound methylamine diazeniumdiolate predict a mechanism involving HNO production via decomposition of the unstable tautomer MeNN+(O-)NHO-. The production of NO at lower pH is predicted to result from fragmentation of the amide/NO adduct upon protonation of the amine nitrogen.
Dutton, Andrew S.; Suhrada, Christopher P.; Miranda, Katrina M.; Wink, David A.; Fukuto, Jon M.; Houk, K. N.
2011-01-01
Isopropylamine diazeniumdiolate, IPA/NO, the product of the reaction of isopropylamine and nitric oxide, NO, decomposes in a pH dependent manner to afford nitroxyl, HNO, in the pH range of 13 to above 5 and NO below pH 7. Theoretical studies using B3LYP/6-311+G(d) density functional theory, the PCM and CPCM solvation models and the high accuracy CBS-QB3 method on the simplified model compound, methylamine diazeniumdiolate, predict a mechanism involving HNO production via decomposition of the unstable tautomer MeNN+(O−)NHO−. The production of NO at lower pH is predicted to result from fragmentation of the amide/NO adduct upon protonation of the amine nitrogen. PMID:16529464
An Approximate Method for Calculation of Fluid Force and Response of A Circular Cylinder at Lock-in
Institute of Scientific and Technical Information of China (English)
WANG Yi
2008-01-01
In this paper, equations calculating lift force of a rigid circular cylinder at lock-in in uniform flow are deduced in detail. Besides, equations calculating the lift force on a long flexible circular cylinder at lock-in are deduced based on mode analysis of a multi-degree freedom system. The simplified forms of these equations are also given. Furthermore, an approximate method to predict the forces and response of rigid circular cylinders and long flexible circular cylinders at lock-in is introduced in the case of low mass-damping ratio. A method to eliminate one deficiency of these equations is introduced. Comparison with experimental results shows the effectiveness of this approximate method.
Giantomassi, Matteo; Huhs, Georg; Waroquiers, David; Gonze, Xavier
2014-03-01
Many-Body Perturbation Theory (MBPT) defines a rigorous framework for the description of excited-state properties based on the Green's function formalism. Within MBPT, one can calculate charged excitations using e.g. Hedin's GW approximation for the electron self-energy. In the same framework, neutral excitations are also well described through the solution of the Bethe-Salpeter equation (BSE). In this talk, we report on the recent developments concerning the parallelization of the MBPT algorithms available in the ABINIT code (www.abinit.org). In particular, we discuss how to improve the parallel efficiency thanks to a hybrid version that employs MPI for the coarse-grained parallelization and OpenMP (a de facto standard for parallel programming on shared memory architectures) for the fine-grained parallelization of the most CPU-intensive parts. Benchmark results obtained with the new implementation are discussed. Finally, we present results for the GW corrections of amorphous SiO2 in the presence of defects and the BSE absorption spectrum. This work has been supported by the Prace project (PaRtnership for Advanced Computing in Europe, http://www.prace-ri.eu).
Directory of Open Access Journals (Sweden)
Yan Zhenzhen
2016-01-01
Full Text Available In order to obtain the Required Safety Egress Time (RSET accurately, traditional engineering calculation method of evacuation time has been optimized in this paper. Several principles and fact situations were used to optimize the method, such as detecting principle of the fire detecting system, reaction characteristics of staff being in urgent situation, evacuating queuing theory, building structure and the plugging at the porthole. Taking a three-storey KTV as an example, two methods are used to illustrate the reliability and scientific reasonability of the calculation result. The result is deduced by comparing the error (less than 2% at an allowable range between two results. One result is calculated by a modified method of engineering calculation method, and the other one is given based on a Steering model of Pathfinder evacuation simulation software. The optimized RSET has a good feasibility and Accuracy.
The rating reliability calculator
Directory of Open Access Journals (Sweden)
Solomon David J
2004-04-01
Full Text Available Abstract Background Rating scales form an important means of gathering evaluation data. Since important decisions are often based on these evaluations, determining the reliability of rating data can be critical. Most commonly used methods of estimating reliability require a complete set of ratings i.e. every subject being rated must be rated by each judge. Over fifty years ago Ebel described an algorithm for estimating the reliability of ratings based on incomplete data. While his article has been widely cited over the years, software based on the algorithm is not readily available. This paper describes an easy-to-use Web-based utility for estimating the reliability of ratings based on incomplete data using Ebel's algorithm. Methods The program is available public use on our server and the source code is freely available under GNU General Public License. The utility is written in PHP, a common open source imbedded scripting language. The rating data can be entered in a convenient format on the user's personal computer that the program will upload to the server for calculating the reliability and other statistics describing the ratings. Results When the program is run it displays the reliability, number of subject rated, harmonic mean number of judges rating each subject, the mean and standard deviation of the averaged ratings per subject. The program also displays the mean, standard deviation and number of ratings for each subject rated. Additionally the program will estimate the reliability of an average of a number of ratings for each subject via the Spearman-Brown prophecy formula. Conclusion This simple web-based program provides a convenient means of estimating the reliability of rating data without the need to conduct special studies in order to provide complete rating data. I would welcome other researchers revising and enhancing the program.
New Arsenic Cross Section Calculations
Energy Technology Data Exchange (ETDEWEB)
Kawano, Toshihiko [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2015-03-04
This report presents calculations for the new arsenic cross section. Cross sections for ^{73,74,75} As above the resonance range were calculated with a newly developed Hauser-Feshbach code, CoH3.
Cosmological Calculations on the GPU
Bard, Deborah; Allen, Mark T; Yepremyan, Hasmik; Kratochvil, Jan M
2012-01-01
Cosmological measurements require the calculation of nontrivial quantities over large datasets. The next generation of survey telescopes (such as DES, PanSTARRS, and LSST) will yield measurements of billions of galaxies. The scale of these datasets, and the nature of the calculations involved, make cosmological calculations ideal models for implementation on graphics processing units (GPUs). We consider two cosmological calculations, the two-point angular correlation function and the aperture mass statistic, and aim to improve the calculation time by constructing code for calculating them on the GPU. Using CUDA, we implement the two algorithms on the GPU and compare the calculation speeds to comparable code run on the CPU. We obtain a code speed-up of between 10 - 180x faster, compared to performing the same calculation on the CPU. The code has been made publicly available.
Directory of Open Access Journals (Sweden)
Martins Juliana R
2010-03-01
Full Text Available Abstract Background Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens. Results The hexamerin genes of the honey bee (hex 70a, hex 70b, hex 70c and hex 110 diverge considerably in structure, so that the overall amino acid identity shared among their deduced protein subunits varies from 30 to 42%. Bioinformatics search for motifs in the respective upstream control regions (UCRs revealed six overrepresented motifs including a potential binding site for Ultraspiracle (Usp, a target of juvenile hormone (JH. The expression of these genes was induced by topical application of JH on worker larvae. The four genes are highly transcribed by the larval fat body, although with significant differences in transcript levels, but only hex 110 and hex 70a are re-induced in the adult fat body in a caste- and sex-specific fashion, workers showing the highest expression. Transcripts for hex 110, hex 70a and hex70b were detected in developing ovaries and testes, and hex 110 was highly transcribed in the ovaries of egg-laying queens. A phylogenetic analysis revealed that HEX 110 is located at the most basal position among the holometabola hexamerins, and like HEX 70a and HEX 70c, it shares potential orthology relationship with hexamerins from other hymenopteran species. Conclusions Striking differences were found in the structure and developmental expression of the four hexamerin genes in the honey bee. The presence of a potential binding site for Usp in the respective 5' UCRs, and the results of experiments on JH level manipulation in vivo support the hypothesis of regulation by JH. Transcript levels and patterns in the fat body
A new formula to calculate activity of superoxide dismutase in indirect assays.
Zhang, Chen; Bruins, Marieke E; Yang, Zhi-Qiang; Liu, Shu-Tao; Rao, Ping-Fan
2016-06-15
To calculate superoxide dismutase (SOD) activity rapidly and accurately by indirect SOD assays, a formula based on the ratio of the catalytic speed of SOD to the reaction speed of the indicator with superoxide anion was deduced. The accuracy of this formula was compared with the conventional formula based on inhibition in five indirect SOD assays. The new formula was validated in nearly the entire SOD activity range, whereas the conventional formula was validated only during inhibition of 40-60%. This formula might also be used for the assays of other enzymes.
Calculation of the Nuclear Transition Charge Density in a Microscopic sdgIBM-1
Institute of Scientific and Technical Information of China (English)
ZHANG Zhan-Jun; SANG Jian-ping; LIU Yong
2000-01-01
Formulae of proton and neutron boson structure functions (BSF's) are deduced in terms of a microscopic approach of sdgIBM (namely, microscopic sdgIBM). For the nucleus 190Os, the value of BSF's is worked out. Due to the high similarity, the maximum F-spin truncation is made under the full-symmetry approximation. Thereafter, calculations of E2 and E4 transition charge densities (TCD's) are performed in the sdgIBM-1. It is found that the E2 and E4 TCD's can be reproduced quite satisfactorily in the uniform frame of microscopic sdgIBM-1.
Formation Enthalpy Calculation of Oxygen Vacancy Defect in Doped Lithium Niobate Crystals
Institute of Scientific and Technical Information of China (English)
QIANG Liang-sheng; LI Yao; TANG Dong-yan; XU Chong-quan; WEI Yong-de
2004-01-01
The relationship between temperature and oxygen vacancy concentration is deduced in this paper. Based on the data of thermal weight-loss experiment, the formation enthalpies of congruent and several doped LN crystals have been calculated. It was found that the formation enthalpy of oxygen vacancies can be decreased evidently by doping valence-changeable ions. The experimental results were discussed and a new reduction process of the photorefractive LN crystal at a relatively low temperature was proposed, and the reduced crystals showed a good effect in practical use.
CALCULATION OF FUZZY RELIABILITYIN THE CASE OF RANDOM STRESSAND FUZZY FATIGUE STRENGTH
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
The fuzzy sets theory is introduced into the fatigue reliability analysis.The concepts of maximizing set and minimizing set are developed to decide the ordering value of each fuzzy number,and these values can be used to determine the order of the fuzzy numbers.On the basis of the works mentioned above,the membership function defining the fuzzy safety event can be calculated,and then the fuzzy reliability in the case of random stress and fuzzy fatigue strength is deduced.An example is given to illustrate the method.
Pérez, Ana G; de la Rosa, Raúl; Pascual, Mar; Sánchez-Ortiz, Araceli; Romero-Segura, Carmen; León, Lorenzo; Sanz, Carlos
2016-01-08
Volatile compounds are responsible for most of the sensory qualities of virgin olive oil and they are synthesized when enzymes and substrates come together as olive fruit is crushed during the industrial process to obtain the oil. Here we have studied the variability among the major volatile compounds in virgin olive oil prepared from the progeny of a cross of Picual and Arbequina olive cultivars (Olea europaea L.). The volatile compounds were isolated by SPME, and analyzed by HRGC-MS and HRGC-FID. Most of the volatile compounds found in the progeny's oil are produced by the enzymes in the so-called lipoxygenase pathway, and they may be clustered into different groups according to their chain length and polyunsaturated fatty acid origin (linoleic and linolenic acids). In addition, a group of compounds derived from amino acid metabolism and two terpenes also contributed significantly to the volatile fraction, some of which had significant odor values in most of the genotypes evaluated. The volatile compound content of the progeny was very varied, widely transgressing the progenitor levels, suggesting that in breeding programs it might be more effective to consider a larger number of individuals within the same cross than using different crosses with fewer individuals. Multivariate analysis allowed genotypes with particularly interesting volatile compositions to be identified and their flavor quality deduced. Copyright © 2015 Elsevier B.V. All rights reserved.
Bae, Chae-Wun; Lee, Joong-Bok; Park, Seung-Yong; Song, Chang-Seon; Lee, Nak-Hyung; Seo, Kun-Ho; Kang, Young-Sun; Park, Choi-Kyu; Choi, In-Soo
2013-08-01
Canine distemper virus (CDV) causes highly contagious respiratory, gastrointestinal, and neurological diseases in wild and domestic animal species. Despite a broad vaccination campaign, the disease is still a serious problem worldwide. In this study, six field CDV strains were isolated from three dogs, two raccoon dogs, and one badger in Korea. The full sequence of the genes encoding fusion (F) and hemagglutinin (H) proteins were compared with those of other CDVs including field and vaccine strains. The phylogenetic analysis for the F and H genes indicated that the two CDV strains isolated from dogs were most closely related to Chinese strains in the Asia-1 genotype. Another four strains were closely related to Japanese strains in the Asia-2 genotype. The six currently isolated strains shared 90.2-92.1% and 88.2-91.8% identities with eight commercial vaccine strains in their nucleotide and amino acid sequences of the F protein, respectively. They also showed 90.1-91.4% and 87.8-90.7% identities with the same vaccine strains in their nucleotide and deduced amino acid sequences of the H protein, respectively. Different N-linked glycosylation sites were identified in the F and H genes of the six isolates from the prototype vaccine strain Onderstepoort. Collectively, these results demonstrate that at least two different CDV genotypes currently exist in Korea. The considerable genetic differences between the vaccine strains and wild-type isolates would be a major factor of the incomplete protection of dogs from CDV infections.
Directory of Open Access Journals (Sweden)
F.H.R. Fagundes
2010-03-01
Full Text Available To illustrate the construction of precursor complementary DNAs, we isolated mRNAs from whole venom samples. After reverse transcription polymerase chain reaction (RT-PCR, we amplified the cDNA coding for a neurotoxic protein, phospholipase A2 D49 (PLA2 D49, from the venom of Crotalus durissus collilineatus (Cdc PLA2. The cDNA encoding Cdc PLA2 from whole venom was sequenced. The deduced amino acid sequence of this cDNA has high overall sequence identity with the group II PLA2 protein family. Cdc PLA2 has 14 cysteine residues capable of forming seven disulfide bonds that characterize this group of PLA2 enzymes. Cdc PLA2 was isolated using conventional Sephadex G75 column chromatography and reverse-phase high performance liquid chromatography (RP-HPLC. The molecular mass was estimated using matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF mass spectrometry. We tested the neuromuscular blocking activities on chick biventer cervicis neuromuscular tissue. Phylogenetic analysis of Cdc PLA2 showed the existence of two lines of N6-PLA2, denominated F24 and S24. Apparently, the sequences of the New World’s N6-F24-PLA2 are similar to those of the agkistrodotoxin from the Asian genus Gloydius. The sequences of N6-S24-PLA2 are similar to the sequence of trimucrotoxin from the genus Protobothrops, found in the Old World.
Douillard, J M; Henry, M
2003-07-15
A very simple route to calculation of the surface energy of solids is proposed because this value is very difficult to determine experimentally. The first step is the calculation of the attractive part of the electrostatic energy of crystals. The partial charges used in this calculation are obtained by using electronegativity equalization and scales of electronegativity and hardness deduced from physical characteristics of the atom. The lattice energies of the infinite crystal and of semi-infinite layers are then compared. The difference is related to the energy of cohesion and then to the surface energy. Very good results are obtained with ice, if one compares with the surface energy of liquid water, which is generally considered a good approximation of the surface energy of ice.
Energy Technology Data Exchange (ETDEWEB)
Decossas, J.L.; Vareille, J.C.; Moliton, J.P.; Teyssier, J.L. (Limoges Univ., 87 (France). Lab. d' Electronique des Polymeres sous Faisceaux Ioniques)
1983-01-01
A fast neutron dosemeter is generally composed of a radiator in which n-p elastic scattering occurs and a detector which registers protons. A theoretical study, and the calculation (FORTRAN program) of the response of such a dosemeter is presented involving two steps: 1) The proton flux emerging from a thick radiator on which monoenergetic neutrons are normally incident is studied. This is characterised by its energy spectrum depending on the neutron energy and on the radiator thickness. 2) Proton detection being achieved with a solid state nuclear track detector whose performance is known, the number of registered tracks are calculated. The dosemeter sensitivity (tracks cm/sup -2/. Sv/sup -1/) is deduced. Then, the calculations show that it is possible to optimise the radiator thickness to obtain the smallest variation in sensitivity with neutron energy. The theoretical results are in good agreement with the experimental ones found in the literature.
Sizeable beta-strength in ^{31}Ar^{ (beta 3p) decay}
DEFF Research Database (Denmark)
T. Koldste, G.; Blank, B.; J. G. Borge, M.
2014-01-01
We present for the first time precise spectroscopic information on the recently discovered decay mode beta-delayed 3p-emission. The detection of the 3p events gives an increased sensitivity to the high energy part of the Gamow-Teller strength distribution from the decay of 31Ar revealing that as ...
A Monochromatic electron neutrino beam
Lindroos, Mats; Burguet-Castell, J; Espinoza, C
In the last few years spectacular results have been achieved with the demonstration of non vanishingneutrino masses and flavour mixing. Here, a novel method to create a monochromaticneutrino beam, an old dream for neutrino physics, is described based on the recent discoveryof nuclei with fast decay through electron-capture to Gamow-Teller resonances in super allowedtransitions.
Microscopic structure of charge-exchange spin-isospin modes through decay measurements
Harakeh, M.N.
1998-01-01
The study of particle decay of charge-exchange giant resonances (CEGR) furnishes information on their microscopic structure. Furthermore, gamma decay of CEGR call help to unravel their structure. For example, the gamma-decay of the Gamow-Teller (GT) resonance to the isobaric analogue state (IAS) poi
Arole, S; Gorringe, T P; Hasinoff, M D; Kovash, M A; Kuzmin, V; Moftah, B A; Sedlar, R; Stocki, T J; Tetereva, T
2002-01-01
We report measurements of $\\gamma$--ray spectra from muon capture on $^{35}$Cl. For the allowed Gamow--Teller transitions to the $^{35}$S$(2939, 3/2^+)$ state and the $^{35}$S$(3421, 5/2^+)$ state we obtained their capture rates, hyperfine dependences and $\\gamma$--$\
Frekers, D.; Adachi, T.; Akimune, H.; Alanssari, M.; Brown, B. A.; Cleveland, B. T.; Ejiri, H.; Fujita, H.; Fujita, Y.; Fujiwara, M.; Gavrin, V. N.; Harakeh, M. N.; Hatanaka, K.; Holl, M.; Iwamoto, C.; Lennarz, A.; Okamoto, A.; Okamura, H.; Suzuki, T.; Tamii, A.
2015-01-01
A precision measurement of the Ga-71(He-3,t)Ge-71 charge-exchange reaction was performed. By using a rather complete set of theoretical form factors to describe the cross-section angular distributions over a large angular range, the Gamow-Teller strength distribution up to the effective neutron-sepa
Equilibrium calculations of firework mixtures
Energy Technology Data Exchange (ETDEWEB)
Hobbs, M.L. [Sandia National Labs., Albuquerque, NM (United States); Tanaka, Katsumi; Iida, Mitsuaki; Matsunaga, Takehiro [National Inst. of Materials and Chemical Research, Tsukuba, Ibaraki (Japan)
1994-12-31
Thermochemical equilibrium calculations have been used to calculate detonation conditions for typical firework components including three report charges, two display charges, and black powder which is used as a fuse or launch charge. Calculations were performed with a modified version of the TIGER code which allows calculations with 900 gaseous and 600 condensed product species at high pressure. The detonation calculations presented in this paper are thought to be the first report on the theoretical study of firework detonation. Measured velocities for two report charges are available and compare favorably to predicted detonation velocities. However, the measured velocities may not be true detonation velocities. Fast deflagration rather than an ideal detonation occurs when reactants contain significant amounts of slow reacting constituents such as aluminum or titanium. Despite such uncertainties in reacting pyrotechnics, the detonation calculations do show the complex nature of condensed phase formation at elevated pressures and give an upper bound for measured velocities.
Global nuclear-structure calculations
Energy Technology Data Exchange (ETDEWEB)
Moeller, P.; Nix, J.R.
1990-04-20
The revival of interest in nuclear ground-state octupole deformations that occurred in the 1980's was stimulated by observations in 1980 of particularly large deviations between calculated and experimental masses in the Ra region, in a global calculation of nuclear ground-state masses. By minimizing the total potential energy with respect to octupole shape degrees of freedom in addition to {epsilon}{sub 2} and {epsilon}{sub 4} used originally, a vastly improved agreement between calculated and experimental masses was obtained. To study the global behavior and interrelationships between other nuclear properties, we calculate nuclear ground-state masses, spins, pairing gaps and {Beta}-decay and half-lives and compare the results to experimental qualities. The calculations are based on the macroscopic-microscopic approach, with the microscopic contributions calculated in a folded-Yukawa single-particle potential.
CALCULATION OF LASER CUTTING COSTS
Directory of Open Access Journals (Sweden)
Bogdan Nedic
2016-09-01
Full Text Available The paper presents description methods of metal cutting and calculation of treatment costs based on model that is developed on Faculty of mechanical engineering in Kragujevac. Based on systematization and analysis of large number of calculation models of cutting with unconventional methods, mathematical model is derived, which is used for creating a software for calculation costs of metal cutting. Software solution enables resolving the problem of calculating the cost of laser cutting, comparison' of costs made by other unconventional methods and provides documentation that consists of reports on estimated costs.
Calculation of Spectra of Solids:
DEFF Research Database (Denmark)
Lindgård, Per-Anker
1975-01-01
The Gilat-Raubenheimer method simplified to tetrahedron division is used to calculate the real and imaginary part of the dynamical response function for electrons. A frequency expansion for the real part is discussed. The Lindhard function is calculated as a test for numerical accuracy. The condu...
Calculator. Owning a Small Business.
Parma City School District, OH.
Seven activities are presented in this student workbook designed for an exploration of small business ownership and the use of the calculator in this career. Included are simulated situations in which students must use a calculator to compute property taxes; estimate payroll taxes and franchise taxes; compute pricing, approximate salaries,…
Calculating charged defects using CRYSTAL
Bailey, Christine L.; Liborio, Leandro; Mallia, Giuseppe; Tomić, Stanko; Harrison, Nicholas M.
2010-07-01
The methodology for the calculation of charged defects using the CRYSTAL program is discussed. Two example calculations are used to illustrate the methodology: He+ ions in a vacuum and two intrinsic charged defects, Cu vacancies and Ga substitution for Cu, in the chalcopyrite CuGaS2.
Economic calculation in socialist countries
Ellman, M.; Durlauf, S.N.; Blume, L.E.
2008-01-01
In the 1930s, when the classical socialist system emerged, economic decisions were based not on detailed and precise economic methods of calculation but on rough and ready political methods. An important method of economic calculation - particularly in the post-Stalin period - was that of
Institute of Scientific and Technical Information of China (English)
罗辽复; 贾孟文
2002-01-01
Evolutionary distance is defined by oligonucleotide (n-bases) frequency difference of two sequences.Phylogenetic tree is reconstructed using a set of 16S (18S) rRNA sequences and the definition of distance.The quality of trees generally improves with increasing n and reaches a plateau of best fit at n=7 or 8.So,the 7-mer or 8-mer frequencies provides a basis to describe rRNA evolution.Then,a group of 7-mers are deduced which are correlate well with evolution.Evolution-related conservative words longer than 7 bases for Bacteria and Archaea in 16S rRNA sequences have been found.They are highly conserved in nearly all species of a kingdom (or a sub-kingdom) and are located on nearly same sites of sequences. The structural meaning of these conservative words is discussed briefly.%据寡核苷(n核苷)频数差定义进化距离,由此构成16s rRNA进化树,当n=7,8时和实验资料符合很好,在寻找出全部进化相关的7-核苷的基础上,本文进一步求得了长度大于7的保守字,它们在一个界别中的诸物种中高度保守,并出现于核糖体序列的基本相同的位置上,这些保守字对于核糖体的早期进化至关重要.
一种地炮作战效能评估动态推演方法%A Dynamic Deducing Method of Field Artillery Operational Effectiveness Assessment
Institute of Scientific and Technical Information of China (English)
朱江; 俞杰; 赵定烽
2011-01-01
Traditional assessment method cannot fit current needs of information war. As for it,a new dynamic deducing method which based on MAS (Multi-Agent System)and CAS (Complex Adaptative System) technology is used to assess operational effectiveness of field artillery. In this method,from micro viewpoint,agent is bulit in mulit-resolution way, and from macro viewpont, the dynamic confront process of campaign is modeled. The method can solute the problem of the traditional static assessment methods such as not reflecting dynamicly confrontting with enemy .leaving aside a systematic viewpoind of operation and so on, This is a new idea and method for assesment of artillery operational effectiveness.%为了解决传统地炮作战效能评估方法不能适应信息化条件下我军需求的问题,基于复杂适应系统理论和多智能体建模技术提出动态推演方法进行地炮作战效能评估.微观层面对智能体进行多分辨率建模,宏观层面模拟作战动态对抗过程,能有效地解决传统评估方法难以适应复杂环境,难以反映动态对抗,割裂体系逐个评估,割裂人与武器联系的不足.该方法为研究地炮效能评估提供了新思路.
Closure and Sealing Design Calculation
Energy Technology Data Exchange (ETDEWEB)
T. Lahnalampi; J. Case
2005-08-26
The purpose of the ''Closure and Sealing Design Calculation'' is to illustrate closure and sealing methods for sealing shafts, ramps, and identify boreholes that require sealing in order to limit the potential of water infiltration. In addition, this calculation will provide a description of the magma that can reduce the consequences of an igneous event intersecting the repository. This calculation will also include a listing of the project requirements related to closure and sealing. The scope of this calculation is to: summarize applicable project requirements and codes relating to backfilling nonemplacement openings, removal of uncommitted materials from the subsurface, installation of drip shields, and erecting monuments; compile an inventory of boreholes that are found in the area of the subsurface repository; describe the magma bulkhead feature and location; and include figures for the proposed shaft and ramp seals. The objective of this calculation is to: categorize the boreholes for sealing by depth and proximity to the subsurface repository; develop drawing figures which show the location and geometry for the magma bulkhead; include the shaft seal figures and a proposed construction sequence; and include the ramp seal figure and a proposed construction sequence. The intent of this closure and sealing calculation is to support the License Application by providing a description of the closure and sealing methods for the Safety Analysis Report. The closure and sealing calculation will also provide input for Post Closure Activities by describing the location of the magma bulkhead. This calculation is limited to describing the final configuration of the sealing and backfill systems for the underground area. The methods and procedures used to place the backfill and remove uncommitted materials (such as concrete) from the repository and detailed design of the magma bulkhead will be the subject of separate analyses or calculations. Post
Unique first-forbidden β-decay transitions in odd-odd and even-even heavy nuclei
Nabi, Jameel-Un; Çakmak, Necla; Majid, Muhammad; Selam, Cevad
2017-01-01
The allowed Gamow-Teller (GT) transitions are the most common weak nuclear processes of spin-isospin (στ) type. These transitions play a key role in numerous processes in the domain of nuclear physics. Equally important is their contribution in astrophysics, particularly in nuclear synthesis and supernova-explosions. In situations where allowed GT transitions are not favored, first-forbidden transitions become significant, specifically in medium heavy and heavy nuclei. For neutron-rich nuclei, first-forbidden transitions are favored mainly due to the phase-space amplification for these transitions. In this work we calculate the allowed GT as well as unique first-forbidden (U1F) | ΔJ | = 2 transitions strength in odd-odd and even-even nuclei in mass range 70 ≤ A ≤ 214. Two different pn-QRPA models were used with a schematic separable interaction to calculate GT and U1F transitions. The inclusion of U1F strength improved the overall comparison of calculated terrestrial β-decay half-lives in both models. The ft values and reduced transition probabilities for the 2- ⟷0+ transitions were also calculated. We compared our calculations with the previously reported correlated RPA calculation and experimental results. Our calculations are in better agreement with measured data. For stellar applications we further calculated the allowed GT and U1F weak rates. These include β±-decay rates and electron/positron capture rates of heavy nuclei in stellar matter. Our study shows that positron and electron capture rates command the total weak rates of these heavy nuclei at high stellar temperatures.
Practical astronomy with your calculator
Duffett-Smith, Peter
1989-01-01
Practical Astronomy with your Calculator, first published in 1979, has enjoyed immense success. The author's clear and easy to follow routines enable you to solve a variety of practical and recreational problems in astronomy using a scientific calculator. Mathematical complexity is kept firmly in the background, leaving just the elements necessary for swiftly making calculations. The major topics are: time, coordinate systems, the Sun, the planetary system, binary stars, the Moon, and eclipses. In the third edition there are entirely new sections on generalised coordinate transformations, nutr
The Collective Practice of Calculation
DEFF Research Database (Denmark)
Schrøder, Ida
on the idea that professions are hybrids by introducing the notion of qualculation as an entry point to investigate decision-making in child protection work as an extreme case of calculating on the basis of other elements than quantitative numbers. The analysis reveals that it takes both calculation...... and judgement to reach decisions to invest in social services. The line is not drawn between the two, but between the material arrangements that make decisions possible. This implies that the insisting on qualitatively based decisions gives the professionals agency to collectively engage in practical...... arrangements that affords calculations of both qualitative measures of the individual case and distant accounting numbers....
Transfer Area Mechanical Handling Calculation
Energy Technology Data Exchange (ETDEWEB)
B. Dianda
2004-06-23
This calculation is intended to support the License Application (LA) submittal of December 2004, in accordance with the directive given by DOE correspondence received on the 27th of January 2004 entitled: ''Authorization for Bechtel SAX Company L.L. C. to Include a Bare Fuel Handling Facility and Increased Aging Capacity in the License Application, Contract Number DE-AC28-01R W12101'' (Arthur, W.J., I11 2004). This correspondence was appended by further Correspondence received on the 19th of February 2004 entitled: ''Technical Direction to Bechtel SAIC Company L.L. C. for Surface Facility Improvements, Contract Number DE-AC28-OIRW12101; TDL No. 04-024'' (BSC 2004a). These documents give the authorization for a Fuel Handling Facility to be included in the baseline. The purpose of this calculation is to establish preliminary bounding equipment envelopes and weights for the Fuel Handling Facility (FHF) transfer areas equipment. This calculation provides preliminary information only to support development of facility layouts and preliminary load calculations. The limitations of this preliminary calculation lie within the assumptions of section 5 , as this calculation is part of an evolutionary design process. It is intended that this calculation is superseded as the design advances to reflect information necessary to support License Application. The design choices outlined within this calculation represent a demonstration of feasibility and may or may not be included in the completed design. This calculation provides preliminary weight, dimensional envelope, and equipment position in building for the purposes of defining interface variables. This calculation identifies and sizes major equipment and assemblies that dictate overall equipment dimensions and facility interfaces. Sizing of components is based on the selection of commercially available products, where applicable. This is not a specific recommendation for the future use
Calculation of Rydberg interaction potentials
Weber, Sebastian; Tresp, Christoph; Menke, Henri; Urvoy, Alban; Firstenberg, Ofer; Büchler, Hans Peter; Hofferberth, Sebastian
2017-07-01
The strong interaction between individual Rydberg atoms provides a powerful tool exploited in an ever-growing range of applications in quantum information science, quantum simulation and ultracold chemistry. One hallmark of the Rydberg interaction is that both its strength and angular dependence can be fine-tuned with great flexibility by choosing appropriate Rydberg states and applying external electric and magnetic fields. More and more experiments are probing this interaction at short atomic distances or with such high precision that perturbative calculations as well as restrictions to the leading dipole-dipole interaction term are no longer sufficient. In this tutorial, we review all relevant aspects of the full calculation of Rydberg interaction potentials. We discuss the derivation of the interaction Hamiltonian from the electrostatic multipole expansion, numerical and analytical methods for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up to higher multipole orders on a desktop computer. Finally, we present example calculations showing the relevance of the full interaction calculation to current experiments. Our software for calculating Rydberg potentials including all features discussed in this tutorial is available as open source.
A Romberg Integral Spreadsheet Calculator
Directory of Open Access Journals (Sweden)
Kim Gaik Tay
2015-04-01
Full Text Available Motivated by the work of Richardson’s extrapolation spreadsheet calculator up to level 4 to approximate definite differentiation, we have developed a Romberg integral spreadsheet calculator to approximate definite integral. The main feature of this version of spreadsheet calculator is a friendly graphical user interface developed to capture the needed information to solve the integral by Romberg method. Users simply need to enter the variable in the integral, function to be integrated, lower and upper limits of the integral, select the desired accuracy of computation, select the exact function if it exists and lastly click the Compute button which is associated with VBA programming written to compute Romberg integral table. The full solution of the Romberg integral table up to any level can be obtained quickly and easily using this method. The attached spreadsheet calculator together with this paper helps educators to prepare their marking scheme easily and assist students in checking their answers instead of reconstructing the answers from scratch. A summative evaluation of this Romberg Spreadsheet Calculator has been conducted by involving 36 students as sample. The data was collected using questionnaire. The findings showed that the majority of the students agreed that the Romberg Spreadsheet Calculator provides a structured learning environment that allows learners to be guided through a step-by-step solution.
Directory of Open Access Journals (Sweden)
Harrison Marcus
2010-12-01
deduce that S. lividans 66 and TK24, both deficient in the glyoxylate bypass, possess an alternative metabolic mechanism for the assimilation of C2 compounds. Given that streptomycetes generally display high genetic instability it is envisaged that these high-density arrays will find application for rapid assessment of genome content (particularly amplifications/deletions in mutational studies of S. coelicolor and related species.
Directory of Open Access Journals (Sweden)
J. Gómez-Enri
2004-01-01
Full Text Available The exponential increase in the use of altimeter data in oceanographic studies in the past two decades has improved the knowledge of the processes that govern the interaction between the ocean and the atmosphere. One of these processes is the response of the ocean to atmospheric pressure variations, which has been deeply analysed in the past. That response is based on the isostatic assumption used to establish a standard correction for altimetric purposes, the Inverse Barometer Correction (IBC. As a general rule, the ocean goes up/down 1cm when the atmospheric pressure goes down/up 1mbar. However, in light of recent works in some oceanic regions, discrepancies arise when the real response is compared to the hypothetical one. It is important to quantify this discrepancy, in order to improve the accuracy of the correction, which is one of the most significant geophysical corrections applied to altimeter records. Some aspects of this response remain unclear, such as the real space-temporal scales where IBC can be applied, the influence of wind, non-isostatic atmospheric pressure-driven signals, and the effect of aliasing from high frequency signals. This paper is an attempt to gain insight into this phenomenon. The data used are the residuals obtained between sea surface heights from the ERS-2 altimeter and the outputs of a global barotropic ocean model. Significant departures from the hypothetical isostatic response in all data series (spatial and temporal domain have been found, especially in the case of altimeter records. By applying the collinear track method, we observe that the estimated Atlantic Ocean response is quite similar to the one deduced from the isostatic assumption at all latitudinal bands. Nonetheless, the Indian and Pacific Oceans show important departures from the hypothetical value at low latitudes. Results obtained with the crossover track method show important deviations at low latitudes in the three basins. In
Institute of Scientific and Technical Information of China (English)
沈孟育; 刘秋生; 张增产
1996-01-01
An efficient numerical method for calculating the three-dimensional transonic flows in turbomachinery is proposed. Instead of the Euler equation, streamsurface-governing equations are deduced in the generalized von Mises coordinate system to reflect the flow feature in turbomachinery. Its main advantage is that it is easier to specify more reasonable initial values, i.e. initial streamsurface position, thus accelerating the convergence rate of the iteration process. Moreover, to use the generalized von Mises coordinates makes the present method capable of incorporating the calculation of the flow field, design and modification of the blade contour into a unified algorithm. A rotated finite difference scheme for the streamsurface-governing equations is constructed, and a new measure is presented to deal with the double-value problem of the velocity and density caused by the application of the stream functions as coordinates in the transonic flow. Three test cases were considered with the present approach
Institute of Scientific and Technical Information of China (English)
E.A.IZZHEUROV
2009-01-01
The first resonant(anti-resonant)frequency and sound absorption coefficient of metal rubber(MR) material are theoretically studied with hard backed samples and with air layer.The equations of the first resonant and anti-resonant frequencies of MR are deduced from the undamped propagation characteristics of porous material.The first resonant and anti-resonance sound absorption coefficients are induced according to the theoretical formula for the acoustic characteristic parameters of MR,and the former is modified while the energy consumption at resonance is taken into consideration.The good agreement between the calculation results of these resonant sound absorption parameters and the experimental results verifies the effectiveness of this calculation method for the performance evaluation of MR as a sound absorption material.
Institute of Scientific and Technical Information of China (English)
WU GuoQi; AO HongRui; JIANG HongYuan; E.A.IZZHEUROV
2009-01-01
The first resonant(anti-resonant)frequency and sound absorption coefficient of metal rubber(MR)material are theoretically studied with hard backed samples and with air layer.The equations of the first resonant and anti-resonant frequencies of MR are deduced from the undamped propagation characteristics of porous material.The first resonant and anti-resonance sound absorption coefficients are induced according to the theoretical formula for the acoustic characteristic parameters of MR,and the former is modified while the energy consumption at resonance is taken into consideration.The good agreement between the calculation results of these resonant sound absorption parameters and the experimental results verifies the effectiveness of this calculation method for the performance evaluation of MR as a sound absorption material.
A model for calculating a.c. losses in multistage superconducting cables
Schild, T.; Ciazynski, D.
Superconducting magnets in tokamaks for fusion experiments are subjected to fast variations in magnetic field. As the high current conductors used in these magnets are made of multistage cables, these variations induce interstrand coupling currents that create losses. These losses are usually characterized by the so-called time constant of the conductor. A model is given to calculate this time constant. Working formulas are also proposed to calculate the current induced in the different cabling stages. This model takes into account the strand characteristics and the detailed cabling pattern. Using it, a method is also given to deduce the time constant from resistive measurements. The influence of the resistive barrier (chrome plating, CuNi shell, outer bronze matrix) is pointed out. Finally, this model is applied to a conductor that is foreseen for the toroidal coils of the International Thermonuclear Experimental Reactor (ITER).
An Ab-Initio Calculation of Raman Spectra of Binary Sodium Silicates
Institute of Scientific and Technical Information of China (English)
尤静林; 蒋国昌; 侯怀宇; 陈辉; 吴永全; 徐匡迪
2004-01-01
Raman spectra of binary sodium silicates are calculated by self-consistent field (SCF) molecular orbital ab initio calculation of the quantum chemical method with several poly silicon-oxygen tetrahedral model clusters when both the basis sets of 6-31 G and 6-31 G(d) are applied. The symmetric stretching vibrational frequency of non-bridging oxygen in a high frequency range and its Raman optical activity and scattering cross section are deduced and analysed. The correlation between this vibrational Raman shift and its microscopic environment of the silicon-oxygen tetrahedron is found based on interior stress of configuration, which depends on the connecting topology of adjacent silicon-oxygen tetrahedra (SiOT). A newly established empirical stress index of tetrahedron is introduced to elucidate the above relationship.
Zhang, Zhen; Xia, Changliang; Yan, Yan; Geng, Qiang; Shi, Tingna
2017-08-01
Due to the complicated rotor structure and nonlinear saturation of rotor bridges, it is difficult to build a fast and accurate analytical field calculation model for multilayer interior permanent magnet (IPM) machines. In this paper, a hybrid analytical model suitable for the open-circuit field calculation of multilayer IPM machines is proposed by coupling the magnetic equivalent circuit (MEC) method and the subdomain technique. In the proposed analytical model, the rotor magnetic field is calculated by the MEC method based on the Kirchhoff's law, while the field in the stator slot, slot opening and air-gap is calculated by subdomain technique based on the Maxwell's equation. To solve the whole field distribution of the multilayer IPM machines, the coupled boundary conditions on the rotor surface are deduced for the coupling of the rotor MEC and the analytical field distribution of the stator slot, slot opening and air-gap. The hybrid analytical model can be used to calculate the open-circuit air-gap field distribution, back electromotive force (EMF) and cogging torque of multilayer IPM machines. Compared with finite element analysis (FEA), it has the advantages of faster modeling, less computation source occupying and shorter time consuming, and meanwhile achieves the approximate accuracy. The analytical model is helpful and applicable for the open-circuit field calculation of multilayer IPM machines with any size and pole/slot number combination.
Thermodynamic equilibrium calculation on preparation of copper oxalate precursor powder
Institute of Scientific and Technical Information of China (English)
FAN You-qi; ZHANG Chuan-fu; ZHAN Jing; WU Jian-hui
2008-01-01
According to the principles of simultaneous equilibrium and mass balance, a series of thermodynamic equilibrium equations of Cu2+ -C2O2-4 -NH3-NH4+-H2O system at ambient temperature were deduced theoretically and the logarithm concentration versus pH value (lg[Cu2+]T-pH) diagrams at different solution compositions were drawn. The results show that when pH is below 5.0, copper ion reacts with C2O42- directly and the morphology of copper precursor powder is of pie-shape; when pH is above 5.0, copper ion coordinates with ammonia, and the precipitation proceeds slowly accompanying with the release of copper ions from the multi-coordinated Cu(NH3)n2+ (n =1, 2, …, 5) and the morphologies of copper precursor powder are respectively of rod aggregation shape (when 5.0＜pH＜8.0) and of rod-shape (when pH＞8.0). Some experiments were performed to confirm the relation between the total concentration of copper ion and pH value. It is shown that the thermodynamic mathematical model is correct and the calculated values are basically accurate.
SIMULATE-4 pin power calculations
Energy Technology Data Exchange (ETDEWEB)
Bahadir, T. [Studsvik Scandpower, Inc., 1087 Beacon St., Newton, MA 02459 (United States); Lindahl, S. Oe [Studsvik Scandpower AB, Hantverkargatan 2A, SE-722 12 Vasteraas (Sweden)
2006-07-01
A new pin power reconstruction module has been implemented in Studsvik Scandpower's next generation nodal code, SIMULATE-4. Heterogeneous pin powers are calculated by modulating multi-group pin powers from the sub-mesh solver of SIMULATE-4 with pin form factors from single-assembly CASMO-5 lattice calculations. The multi-group pin power model captures instantaneous spectral effects, and actinide tracking on the assembly sub-mesh describes exposure-induced pin power variations. Model details and verification tests against high order multi-assembly transport methods are presented. The accuracy of the new methods is also demonstrated by comparing SIMULATE-4 calculations with measured critical experiment pin powers. (authors)
Insertion device calculations with mathematica
Energy Technology Data Exchange (ETDEWEB)
Carr, R. [Stanford Synchrotron Radiation Lab., CA (United States); Lidia, S. [Univ. of California, Davis, CA (United States)
1995-02-01
The design of accelerator insertion devices such as wigglers and undulators has usually been aided by numerical modeling on digital computers, using code in high level languages like Fortran. In the present era, there are higher level programming environments like IDL{reg_sign}, MatLab{reg_sign}, and Mathematica{reg_sign} in which these calculations may be performed by writing much less code, and in which standard mathematical techniques are very easily used. The authors present a suite of standard insertion device modeling routines in Mathematica to illustrate the new techniques. These routines include a simple way to generate magnetic fields using blocks of CSEM materials, trajectory solutions from the Lorentz force equations for given magnetic fields, Bessel function calculations of radiation for wigglers and undulators and general radiation calculations for undulators.
MFTF-B performance calculations
Energy Technology Data Exchange (ETDEWEB)
Thomassen, K.I.; Jong, R.A.
1982-12-06
In this report we document the operating scenario models and calculations as they exist and comment on those aspects of the models where performance is sensitive to the assumptions that are made. We also focus on areas where improvements need to be made in the mathematical descriptions of phenomena, work which is in progress. To illustrate the process of calculating performance, and to be very specific in our documentation, part 2 of this report contains the complete equations and sequence of calculations used to determine parameters for the MARS mode of operation in MFTF-B. Values for all variables for a particular set of input parameters are also given there. The point design so described is typical, but should be viewed as a snapshot in time of our ongoing estimations and predictions of performance.
Molecular calculations with B functions
Steinborn, E O; Ema, I; López, R; Ramírez, G
1998-01-01
A program for molecular calculations with B functions is reported and its performance is analyzed. All the one- and two-center integrals, and the three-center nuclear attraction integrals are computed by direct procedures, using previously developed algorithms. The three- and four-center electron repulsion integrals are computed by means of Gaussian expansions of the B functions. A new procedure for obtaining these expansions is also reported. Some results on full molecular calculations are included to show the capabilities of the program and the quality of the B functions to represent the electronic functions in molecules.
Friction and wear calculation methods
Kragelsky, I V; Kombalov, V S
1981-01-01
Friction and Wear: Calculation Methods provides an introduction to the main theories of a new branch of mechanics known as """"contact interaction of solids in relative motion."""" This branch is closely bound up with other sciences, especially physics and chemistry. The book analyzes the nature of friction and wear, and some theoretical relationships that link the characteristics of the processes and the properties of the contacting bodies essential for practical application of the theories in calculating friction forces and wear values. The effect of the environment on friction and wear is a
Multifragmentation calculated with relativistic forces
Feldmeier, H; Papp, G
1995-01-01
A saturating hamiltonian is presented in a relativistically covariant formalism. The interaction is described by scalar and vector mesons, with coupling strengths adjusted to the nuclear matter. No explicit density depe ndence is assumed. The hamiltonian is applied in a QMD calculation to determine the fragment distribution in O + Br collision at different energies (50 -- 200 MeV/u) to test the applicability of the model at low energies. The results are compared with experiment and with previous non-relativistic calculations. PACS: 25.70Mn, 25.75.+r
Methods for Melting Temperature Calculation
Hong, Qi-Jun
Melting temperature calculation has important applications in the theoretical study of phase diagrams and computational materials screenings. In this thesis, we present two new methods, i.e., the improved Widom's particle insertion method and the small-cell coexistence method, which we developed in order to capture melting temperatures both accurately and quickly. We propose a scheme that drastically improves the efficiency of Widom's particle insertion method by efficiently sampling cavities while calculating the integrals providing the chemical potentials of a physical system. This idea enables us to calculate chemical potentials of liquids directly from first-principles without the help of any reference system, which is necessary in the commonly used thermodynamic integration method. As an example, we apply our scheme, combined with the density functional formalism, to the calculation of the chemical potential of liquid copper. The calculated chemical potential is further used to locate the melting temperature. The calculated results closely agree with experiments. We propose the small-cell coexistence method based on the statistical analysis of small-size coexistence MD simulations. It eliminates the risk of a metastable superheated solid in the fast-heating method, while also significantly reducing the computer cost relative to the traditional large-scale coexistence method. Using empirical potentials, we validate the method and systematically study the finite-size effect on the calculated melting points. The method converges to the exact result in the limit of a large system size. An accuracy within 100 K in melting temperature is usually achieved when the simulation contains more than 100 atoms. DFT examples of Tantalum, high-pressure Sodium, and ionic material NaCl are shown to demonstrate the accuracy and flexibility of the method in its practical applications. The method serves as a promising approach for large-scale automated material screening in which
Charon, E.; Aléon, J.; Rouzaud, J.-N.
2014-10-01
Lodran. Carbon phases in Lodran would have been formed by the secondary carbonization of hydrocarbon fluids released during the primary carbonization of IOM. In the framework of this model, the C isotopic compositions can be reproduced using Rayleigh distillation at each carbonization step and the N isotopic compositions can be understood as resulting from the variable loss and preservation of 15N-rich nitriles (δ15N ∼ +800‰) and 15N-poor pyrroles (δ15N = -140‰) during carbonization. The combined interpretation of the temperatures deduced from this model, petrographic cooling rates, and thermochronological indicators suggest that the CI-CM IOM could have been introduced in the parent-body by an impact, about 10 Myr after solar system formation.
Hughes, R. O.; Beausang, C. W.; Ross, T. J.; Burke, J. T.; Casperson, R. J.; Cooper, N.; Escher, J. E.; Gell, K.; Good, E.; Humby, P.; McCleskey, M.; Saastimoinen, A.; Tarlow, T. D.; Thompson, I. J.
2014-07-01
The Pu236(n,f), Pu237(n,f) and Pu238(n,f) cross sections have been inferred by utilizing the surrogate ratio method. Targets of Pu239 and U235 were bombarded with 28.5-MeV protons, and the light ion recoils, as well as fission fragments, were detected using the STARS detector array at the K150 Cyclotron at the Texas A&M cyclotron facility. The (p, tf) reaction on Pu239 and U235 targets was used to deduce the σ (Pu236(n ,f))/σ(U232(n,f)) ratio, and the Pu236(n,f) cross section was subsequently determined for En=0.5-7.5 MeV. Similarly, the (p,df) reaction on the same two targets was used to deduce the σ(Pu237(n ,f))/σ(U233(n,f)) ratio, and the Pu237(n,f) cross section was extracted in the energy range En=0.5-7 MeV. The Pu238(n,f) cross section was also deduced by utilizing the (p,p') reaction channel on the same targets. There is good agreement with the recent ENDF/B-VII.1 evaluated cross section data for Pu238(n,f) in the range En=0.5-10.5 MeV and for Pu237(n,f) in the range En=0.5-7 MeV; however, the Pu236(n,f) cross section deduced in the present work is higher than the evaluation between 2 and 7 MeV.
Theoretical Calculation of MMF's Bandwidth
Institute of Scientific and Technical Information of China (English)
LI Xiao-fu; JIANG De-sheng; YU Hai-hu
2004-01-01
The difference between over-filled launch bandwidth (OFL BW) and restricted mode launch bandwidth (RML BW) is described. A theoretical model is founded to calculate the OFL BW of grade index multimode fiber (GI-MMF),and the result is useful to guide the modification of the manufacturing method.
Data Acquisition and Flux Calculations
DEFF Research Database (Denmark)
Rebmann, C.; Kolle, O; Heinesch, B;
2012-01-01
In this chapter, the basic theory and the procedures used to obtain turbulent fluxes of energy, mass, and momentum with the eddy covariance technique will be detailed. This includes a description of data acquisition, pretreatment of high-frequency data and flux calculation....
Calculations for cosmic axion detection
Krauss, L.; Moody, J.; Wilczek, F.; Morris, D. E.
1985-01-01
Calculations are presented, using properly nomalized couplings and masses for Dine-Fischler-Srednicki axions, of power rates and signal temperatures for axion-photon conversion in microwave cavities. The importance of the galactic-halo axion line shape is emphasized. Spin-coupled detection as an alternative to magnetic-field-coupled detection is mentioned.
ITER Port Interspace Pressure Calculations
Energy Technology Data Exchange (ETDEWEB)
Carbajo, Juan J [ORNL; Van Hove, Walter A [ORNL
2016-01-01
The ITER Vacuum Vessel (VV) is equipped with 54 access ports. Each of these ports has an opening in the bioshield that communicates with a dedicated port cell. During Tokamak operation, the bioshield opening must be closed with a concrete plug to shield the radiation coming from the plasma. This port plug separates the port cell into a Port Interspace (between VV closure lid and Port Plug) on the inner side and the Port Cell on the outer side. This paper presents calculations of pressures and temperatures in the ITER (Ref. 1) Port Interspace after a double-ended guillotine break (DEGB) of a pipe of the Tokamak Cooling Water System (TCWS) with high temperature water. It is assumed that this DEGB occurs during the worst possible conditions, which are during water baking operation, with water at a temperature of 523 K (250 C) and at a pressure of 4.4 MPa. These conditions are more severe than during normal Tokamak operation, with the water at 398 K (125 C) and 2 MPa. Two computer codes are employed in these calculations: RELAP5-3D Version 4.2.1 (Ref. 2) to calculate the blowdown releases from the pipe break, and MELCOR, Version 1.8.6 (Ref. 3) to calculate the pressures and temperatures in the Port Interspace. A sensitivity study has been performed to optimize some flow areas.
Affect and Graphing Calculator Use
McCulloch, Allison W.
2011-01-01
This article reports on a qualitative study of six high school calculus students designed to build an understanding about the affect associated with graphing calculator use in independent situations. DeBellis and Goldin's (2006) framework for affect as a representational system was used as a lens through which to understand the ways in which…
Ab Initio Calculations of Oxosulfatovanadates
DEFF Research Database (Denmark)
Frøberg, Torben; Johansen, Helge
1996-01-01
Restricted Hartree-Fock and multi-configurational self-consistent-field calculations together with secondorder perturbation theory have been used to study the geometry, the electron density, and the electronicspectrum of (VO2SO4)-. A bidentate sulphate attachment to vanadium was found to be stable...
Dead reckoning calculating without instruments
Doerfler, Ronald W
1993-01-01
No author has gone as far as Doerfler in covering methods of mental calculation beyond simple arithmetic. Even if you have no interest in competing with computers you'll learn a great deal about number theory and the art of efficient computer programming. -Martin Gardner
Grieder, P. K. F.
1985-01-01
Data obtained from a large set of air shower simulation calculations with use of highly refined hadronic interaction and shower simulation model are presented, in an attempt to solve the problem of primary chemical composition beyond 100,000 GeV total energy. It is rated that high energy hadrons in air showers offer a rather unique primary mass signature and show that the interpretation of high energy muon data is much more ambiguous. Predictions are compared with experimental data.
Grieder, P. K. F.
1985-08-01
Data obtained from a large set of air shower simulation calculations with use of highly refined hadronic interaction and shower simulation model are presented, in an attempt to solve the problem of primary chemical composition beyond 100,000 GeV total energy. It is rated that high energy hadrons in air showers offer a rather unique primary mass signature and show that the interpretation of high energy muon data is much more ambiguous. Predictions are compared with experimental data.
Faddeev calculation of 6 He Lambda Lambda using SU_6 quark-model baryon-baryon interactions
Fujiwara, Y; Miyagawa, K; Suzuki, Y; Sparenberg, J M
2004-01-01
Quark-model hyperon-nucleon and hyperon-hyperon interactions by the Kyoto-Niigata group are applied to the two-Lambda plus alpha system in a new three-cluster Faddeev formalism using two-cluster resonating-group method kernels. The model fss2 gives a reasonable two-Lambda separation energy Delta B_{Lambda Lambda}=1.41 MeV, which is consistent with the recent empirical value, Delta B^{exp}_{Lambda Lambda}=1.01 +/- 0.20 MeV, deduced from the Nagara event. Some important effects that are not taken into account in the present calculation are discussed.
Institute of Scientific and Technical Information of China (English)
Xiaozhi Wu; Shaofeng Wang
2007-01-01
Applying the parametric derivation method, Peierls energy and Peierls stress are calculated with a non-sinusoidal force law in the lattice theory, while the results obtained by the power-series expansion according to sinusoidal law can be deduced as a limiting case of nonsinusoidal law. The simplified expressions of Peierls energy and Peierls stress are obtained for the limit of wide and narrow. Peierls energy and Peierls stress decrease monotonically with the factor of modification of force law. Present results can be used expediently for prediction of the correct order of magnitude of Peierls stress for materials.
Institute of Scientific and Technical Information of China (English)
Jin Wencheng; Zhou Xiaoyong; Li Na
2008-01-01
A numerical model is developed in this paper to calculate the bending moments of flexural members through integration in 3D solid finite element analyses according to the nonlinear constitutive model of concrete and the elastoplastic constitutive model of steel, utilizing the stress condition of the cross-section, considering the destruction characteristic of reinforced concrete members, and based on the plane cross-section assumption. The results of this model give good agreement with those of the classical method. Consequently, we can also deduce the corresponding numerical expression for eccentrically loaded members according to the analysis method.
The Dental Trauma Internet Calculator
DEFF Research Database (Denmark)
Gerds, Thomas Alexander; Lauridsen, Eva Fejerskov; Christensen, Søren Steno Ahrensburg
2012-01-01
Background/Aim Prediction tools are increasingly used to inform patients about the future dental health outcome. Advanced statistical methods are required to arrive at unbiased predictions based on follow-up studies. Material and Methods The Internet risk calculator at the Dental Trauma Guide pro...... were based on the tooth’s root development stage and other risk factors at the time of the injury. Conclusions This article explains the data base, the functionality and the statistical approach of the Internet risk calculator....... injuries: concussion, sub-luxation, extrusion, lateral luxation, intrusion, avulsion, crown fractures without luxation, root fractures and avulsion. The prognoses for pulp necrosis, pulp canal obliteration, infection related root resorption, ankylosis, surface resorption, marginal bone loss and tooth loss...
CONTRIBUTION FOR MINING ATMOSPHERE CALCULATION
Directory of Open Access Journals (Sweden)
Franica Trojanović
1989-12-01
Full Text Available Humid air is an unavoidable feature of mining atmosphere, which plays a significant role in defining the climate conditions as well as permitted circumstances for normal mining work. Saturated humid air prevents heat conduction from the human body by means of evaporation. Consequently, it is of primary interest in the mining practice to establish the relative air humidity either by means of direct or indirect methods. Percentage of water in the surrounding air may be determined in various procedures including tables, diagrams or particular calculations, where each technique has its specific advantages and disadvantages. Classical calculation is done according to Sprung's formula, in which case partial steam pressure should also be taken from the steam table. The new method without the use of diagram or tables, established on the functional relation of pressure and temperature on saturated line, is presented here for the first time (the paper is published in Croatian.
Archimedes' calculations of square roots
Davies, E B
2011-01-01
We reconsider Archimedes' evaluations of several square roots in 'Measurement of a Circle'. We show that several methods proposed over the last century or so for his evaluations fail one or more criteria of plausibility. We also provide internal evidence that he probably used an interpolation technique. The conclusions are relevant to the precise calculations by which he obtained upper and lower bounds on pi.
Parallel plasma fluid turbulence calculations
Energy Technology Data Exchange (ETDEWEB)
Leboeuf, J.N.; Carreras, B.A.; Charlton, L.A.; Drake, J.B.; Lynch, V.E.; Newman, D.E.; Sidikman, K.L.; Spong, D.A.
1994-12-31
The study of plasma turbulence and transport is a complex problem of critical importance for fusion-relevant plasmas. To this day, the fluid treatment of plasma dynamics is the best approach to realistic physics at the high resolution required for certain experimentally relevant calculations. Core and edge turbulence in a magnetic fusion device have been modeled using state-of-the-art, nonlinear, three-dimensional, initial-value fluid and gyrofluid codes. Parallel implementation of these models on diverse platforms--vector parallel (National Energy Research Supercomputer Center`s CRAY Y-MP C90), massively parallel (Intel Paragon XP/S 35), and serial parallel (clusters of high-performance workstations using the Parallel Virtual Machine protocol)--offers a variety of paths to high resolution and significant improvements in real-time efficiency, each with its own advantages. The largest and most efficient calculations have been performed at the 200 Mword memory limit on the C90 in dedicated mode, where an overlap of 12 to 13 out of a maximum of 16 processors has been achieved with a gyrofluid model of core fluctuations. The richness of the physics captured by these calculations is commensurate with the increased resolution and efficiency and is limited only by the ingenuity brought to the analysis of the massive amounts of data generated.
Institute of Scientific and Technical Information of China (English)
HUANG Junhua; LUO Genming; BAI Xiao; TANG Xinyan
2007-01-01
By combining the carbon cycle model with the records of carbonate and organic (kerogen) carbon isotope,this paper presents the calculation of the fraction of organic carbon burial (forg) of beds 23-40 at the global boundary stratotype section and point (GSSP) of the Permian-Triassic boundary at Meishan,Zhejiang Province.The resulting calculation produces two episodes of forg maxima observed to occur at beds 23-24 and 27-29,which respectively corresponds to the two episodic anoxic events indicated by the flourish of green sulfur bacteria.Two episodic forg minima occurred at beds 25-26 and 32-34,generally coincident with the flourish of cyanobacteria (bed 26 and upper part of beds 29 to 34) as shown by the high value of 2-melthyhopnoanes.It appears that the forg is related to the redox conditions,with greater forg values observed under the reductive condition.The relationship between forg and the total organic carbon (TOC) content was complex.The forg value was low at some beds with a high TOC content (such as bed 26),while high observed at some beds with a low TOC content (e.g.bed 27).This association infers the important contribution of primary productivity to the TOC content.The original organic burial could be thus calculated through the configuration of the function of the primary productivity and forg,which can be used to correct the residual TOC measured today.This investigation indicates that compiling the organic-inorganic carbon isotopes with the carbon cycle model favors to understand the fraction of organic carbon burial,providing information for the reconstruction of the coupling among biota,environments and organic burial.
Nazarov, R.; Majevadia, J. S.; Patel, M.; Wenman, M. R.; Balint, D. S.; Neugebauer, J.; Sutton, A. P.
2016-12-01
The elastic dipole tensor is a fundamental quantity relating the elastic field and atomic structure of a point defect. We review three methods in the literature to calculate the dipole tensor and apply them to hydrogen in α -zirconium using density functional theory (DFT). The results are compared with the dipole tensor deduced from earlier experimental measurements of the λ tensor for hydrogen in α -zirconium. There are significant errors with all three methods. We show that calculation of the λ tensor, in combination with experimentally measured elastic constants and lattice parameters, yields dipole tensor components that differ from experimental values by only 10%-20%. There is evidence to suggest that current state-of-the-art DFT calculations underestimate bonding between hydrogen and α -zirconium.
Institute of Scientific and Technical Information of China (English)
2012-01-01
Large-scale doubly-fed induction generator （DFIG） wind turbines are connected to the grid and required to remain grid-connection during faults, the short-circuit current contributed by the generation has become a significant issue. However, the traditional calculation methods aiming at synchronous generators cannot be directly applied to the DFIG wind turbines. A new method is needed to calculate the short-circuit current required by the planning, protection and control of the power grid. The short-circuit transition of DFIG under symmetrical and asymmetric short-circuit conditions are mathematically deduced, and the short-circuit characteristics of DFIG are analyzed. A new method is proposed to calculate the steady-state short-circuit current of DFIG based on the derived expressions. The time-domain simulations are conducted to verify the accuracy of the proposed method.
Baldea, Ioan
2012-01-01
In cases where reorganization is important, present theoretical studies of molecular transport have inherently to resort to models. The Newns-Anderson model is ubiquitous for this purpose but, to author's knowledge, attempts to validate/challenge this model by microscopic calculations are missing in the literature. In this work, results of electronic structure calculations are presented, which demonstrate that the conventional Newns-Anderson model fails to describe redox-active tunneling junctions of recent experimental interest. For the case considered, the ($4, 4^\\prime$)-bipyridine molecule, the failure traces back to the floppy degree of freedom represented by the relative rotation of the two pyridine rings. Expressions that generalize the Newns-Anderson model are deduced, which include significant anharmonicities. These expressions can be straightforwardly utilized as input information in calculations of the partially coherent transport.
Reisfeld, R.; Katz, G.; Jacoboni, C.; De Pape, R.; Drexhage, M. G.; Brown, R. N.; Jørgensen, C. K.
1983-07-01
Fluorozirconate glasses containing 2 mole% ErF 3 were prepared by melting the binary fluorides with ammonium bifluoride under an atmosphere of carbon tetrachloride and argon at 850°C. Absorption spectra of these glasses were obtained and the Judd-Ofelt parameters were calculated. Emission spectra and lifetimes of erbium in fluorozirconate glass, in lead-gallium-zinc fluoride glass, and in yttrium-zirconium oxide crystal were measured and compared with the theoretical calculations. Laser emission lines in these materials are deduced from these measurements. It is suggested that materials doped with erbium may serve as light sources for fiber optic waveguides made from the undoped materials.
Study and Calculation of Feeding Size for R-pendulum Mill%R型摆式磨粉机进料粒度的研究与计算
Institute of Scientific and Technical Information of China (English)
谭开强
2013-01-01
研究推导R型摆式磨粉机进料粒度计算公式,对R型摆式磨料机工况下的进料粒度进行计算,合理的确定R型摆式磨粉机的最大进料尺寸.%This paper researches and deduces the calculation of feeding size for R-pendulum mill.It calculates the feeding size for R-pendulum mill at working condition and reasonably determine the maximum feeding size for R-pendulum mill.
AGING FACILITY CRITICALITY SAFETY CALCULATIONS
Energy Technology Data Exchange (ETDEWEB)
C.E. Sanders
2004-09-10
The purpose of this design calculation is to revise and update the previous criticality calculation for the Aging Facility (documented in BSC 2004a). This design calculation will also demonstrate and ensure that the storage and aging operations to be performed in the Aging Facility meet the criticality safety design criteria in the ''Project Design Criteria Document'' (Doraswamy 2004, Section 4.9.2.2), and the functional nuclear criticality safety requirement described in the ''SNF Aging System Description Document'' (BSC [Bechtel SAIC Company] 2004f, p. 3-12). The scope of this design calculation covers the systems and processes for aging commercial spent nuclear fuel (SNF) and staging Department of Energy (DOE) SNF/High-Level Waste (HLW) prior to its placement in the final waste package (WP) (BSC 2004f, p. 1-1). Aging commercial SNF is a thermal management strategy, while staging DOE SNF/HLW will make loading of WPs more efficient (note that aging DOE SNF/HLW is not needed since these wastes are not expected to exceed the thermal limits form emplacement) (BSC 2004f, p. 1-2). The description of the changes in this revised document is as follows: (1) Include DOE SNF/HLW in addition to commercial SNF per the current ''SNF Aging System Description Document'' (BSC 2004f). (2) Update the evaluation of Category 1 and 2 event sequences for the Aging Facility as identified in the ''Categorization of Event Sequences for License Application'' (BSC 2004c, Section 7). (3) Further evaluate the design and criticality controls required for a storage/aging cask, referred to as MGR Site-specific Cask (MSC), to accommodate commercial fuel outside the content specification in the Certificate of Compliance for the existing NRC-certified storage casks. In addition, evaluate the design required for the MSC that will accommodate DOE SNF/HLW. This design calculation will achieve the objective of providing the
Calculation of gas turbine characteristic
Mamaev, B. I.; Murashko, V. L.
2016-04-01
The reasons and regularities of vapor flow and turbine parameter variation depending on the total pressure drop rate π* and rotor rotation frequency n are studied, as exemplified by a two-stage compressor turbine of a power-generating gas turbine installation. The turbine characteristic is calculated in a wide range of mode parameters using the method in which analytical dependences provide high accuracy for the calculated flow output angle and different types of gas dynamic losses are determined with account of the influence of blade row geometry, blade surface roughness, angles, compressibility, Reynolds number, and flow turbulence. The method provides satisfactory agreement of results of calculation and turbine testing. In the design mode, the operation conditions for the blade rows are favorable, the flow output velocities are close to the optimal ones, the angles of incidence are small, and the flow "choking" modes (with respect to consumption) in the rows are absent. High performance and a nearly axial flow behind the turbine are obtained. Reduction of the rotor rotation frequency and variation of the pressure drop change the flow parameters, the parameters of the stages and the turbine, as well as the form of the characteristic. In particular, for decreased n, nonmonotonic variation of the second stage reactivity with increasing π* is observed. It is demonstrated that the turbine characteristic is mainly determined by the influence of the angles of incidence and the velocity at the output of the rows on the losses and the flow output angle. The account of the growing flow output angle due to the positive angle of incidence for decreased rotation frequencies results in a considerable change of the characteristic: poorer performance, redistribution of the pressure drop at the stages, and change of reactivities, growth of the turbine capacity, and change of the angle and flow velocity behind the turbine.
Semiclassical calculation of decay rates
Bessa, A; Fraga, E S
2008-01-01
Several relevant aspects of quantum-field processes can be well described by semiclassical methods. In particular, the knowledge of non-trivial classical solutions of the field equations, and the thermal and quantum fluctuations around them, provide non-perturbative information about the theory. In this work, we discuss the calculation of the one-loop effective action from the semiclasssical viewpoint. We intend to use this formalism to obtain an accurate expression for the decay rate of non-static metastable states.
Digital calculations of engine cycles
Starkman, E S; Taylor, C Fayette
1964-01-01
Digital Calculations of Engine Cycles is a collection of seven papers which were presented before technical meetings of the Society of Automotive Engineers during 1962 and 1963. The papers cover the spectrum of the subject of engine cycle events, ranging from an examination of composition and properties of the working fluid to simulation of the pressure-time events in the combustion chamber. The volume has been organized to present the material in a logical sequence. The first two chapters are concerned with the equilibrium states of the working fluid. These include the concentrations of var
Yet another partial wave calculator
Energy Technology Data Exchange (ETDEWEB)
Greenwald, Daniel; Rauch, Johannes [TUM, Munich (Germany)
2016-07-01
We will present a new C++ library for partial wave analysis: YAP - yet another partial wave calculator. YAP is intended for amplitude analyses of the decays of spin-0 heavy mesons (principally B and D) to multiple (3, 4, etc.) pseudoscalar mesons but is not hard coded for such situations and is flexible enough to handle other decay scenarios. The library allows for both model dependent and model independent analysis methods. We introduce the software, and demonstrate examples for generating Monte Carlo data efficiently, and for analyzing data (both with the aid of the Bayesian Analysis Toolkit).
Rate calculation with colored noise
Bartsch, Thomas; Benito, R M; Borondo, F
2016-01-01
The usual identification of reactive trajectories for the calculation of reaction rates requires very time-consuming simulations, particularly if the environment presents memory effects. In this paper, we develop a new method that permits the identification of reactive trajectories in a system under the action of a stochastic colored driving. This method is based on the perturbative computation of the invariant structures that act as separatrices for reactivity. Furthermore, using this perturbative scheme, we have obtained a formally exact expression for the reaction rate in multidimensional systems coupled to colored noisy environments.
Electronics reliability calculation and design
Dummer, Geoffrey W A; Hiller, N
1966-01-01
Electronics Reliability-Calculation and Design provides an introduction to the fundamental concepts of reliability. The increasing complexity of electronic equipment has made problems in designing and manufacturing a reliable product more and more difficult. Specific techniques have been developed that enable designers to integrate reliability into their products, and reliability has become a science in its own right. The book begins with a discussion of basic mathematical and statistical concepts, including arithmetic mean, frequency distribution, median and mode, scatter or dispersion of mea
Band calculation of lonsdaleite Ge
Chen, Pin-Shiang; Fan, Sheng-Ting; Lan, Huang-Siang; Liu, Chee Wee
2017-01-01
The band structure of Ge in the lonsdaleite phase is calculated using first principles. Lonsdaleite Ge has a direct band gap at the Γ point. For the conduction band, the Γ valley is anisotropic with the low transverse effective mass on the hexagonal plane and the large longitudinal effective mass along the c axis. For the valence band, both heavy-hole and light-hole effective masses are anisotropic at the Γ point. The in-plane electron effective mass also becomes anisotropic under uniaxial tensile strain. The strain response of the heavy-hole mass is opposite to the light hole.
Energy Technology Data Exchange (ETDEWEB)
Kasugai, Y.; Matsuda, N.; Sakamoto, Y.; Nakashima, H. [Japan Atomic Energy Agency, Tokai-mura, Ibaraki-ken 319-1195 (Japan); Yashima, H. [Research Reactor Inst., Kyoto Univ., Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); Matsumura, H.; Iwase, H.; Hirayama, H. [High Energy Accelerator Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Mokhov, N.; Leveling, A.; Boehnlein, D.; Vaziri, K.; Lauten, G. [Fermi National Accelerator Laboratory, Batavia, IL 87545 (United States); Oishi, K. [Shimizu Corporation, 4-17, Echujima 3-chome, Koto-ku, Tokyo 135-8530 (Japan); Nakamura, T. [Tohoku Univ., Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578 (Japan)
2011-07-01
The Japanese and American Study of Muon Interaction and Neutron detection (JASMIN) collaboration, has been conducting shielding experiments using the Fermilab anti-proton target station (Pbar) shielding assembly. A multi-foil technique was used to measure the high energy neutron spectra, in the range of 1 to 100 MeV, for the target station shielding configuration. The neutron spectra were de-convoluted using a new fitting method. This method is based on the assumption that a neutron spectrum can be expressed as a simple sum of two exponentials. The validity of the fitting method was confirmed by comparison with the results obtained using SAND-II computer code and theoretical calculations. Finally, it was found that there are simple correlations between reaction rates and the adjustable parameters in the fitting function. (authors)
Calculational Tool for Skin Contamination Dose Assessment
Hill, R L
2002-01-01
Spreadsheet calculational tool was developed to automate the calculations preformed for dose assessment of skin contamination. This document reports on the design and testing of the spreadsheet calculational tool.
NATIONAL STORMWATER CALCULATOR USER'S GUIDE ...
The National Stormwater Calculator is a simple to use tool for computing small site hydrology for any location within the US. It estimates the amount of stormwater runoff generated from a site under different development and control scenarios over a long term period of historical rainfall. The analysis takes into account local soil conditions, slope, land cover and meteorology. Different types of low impact development (LID) practices (also known as green infrastructure) can be employed to help capture and retain rainfall on-site. Future climate change scenarios taken from internationally recognized climate change projections can also be considered. The calculator provides planning level estimates of capital and maintenance costs which will allow planners and managers to evaluate and compare effectiveness and costs of LID controls.The calculator’s primary focus is informing site developers and property owners on how well they can meet a desired stormwater retention target. It can be used to answer such questions as:• What is the largest daily rainfall amount that can be captured by a site in either its pre-development, current, or post-development condition?• To what degree will storms of different magnitudes be captured on site?• What mix of LID controls can be deployed to meet a given stormwater retention target?• How well will LID controls perform under future meteorological projections made by global climate change models?• What are the relativ
Flow Field Calculations for Afterburner
Institute of Scientific and Technical Information of China (English)
ZhaoJianxing; LiuQuanzhong; 等
1995-01-01
In this paper a calculation procedure for simulating the coimbustion flow in the afterburner with the heat shield,flame stabilizer and the contracting nozzle is described and evaluated by comparison with experimental data.The modified two-equation κ-ε model is employed to consider the turbulence effects,and the κ-ε-g turbulent combustion model is used to determine the reaction rate.To take into accunt the influence of heat radiation on gas temperature distribution,heat flux model is applied to predictions of heat flux distributions,The solution domain spanned the entire region between centerline and afterburner wall ,with the heat shield represented as a blockage to the mesh.The enthalpy equation and wall boundary of the heat shield require special handling for two passages in the afterburner,In order to make the computer program suitable to engineering applications,a subregional scheme is developed for calculating flow fields of complex geometries.The computational grids employed are 100×100 and 333×100(non-uniformly distributed).The numerical results are compared with experimental data,Agreement between predictions and measurements shows that the numerical method and the computational program used in the study are fairly reasonable and appopriate for primary design of the afterburner.
Dissecting Reactor Antineutrino Flux Calculations
Sonzogni, A. A.; McCutchan, E. A.; Hayes, A. C.
2017-09-01
Current predictions for the antineutrino yield and spectra from a nuclear reactor rely on the experimental electron spectra from 235U, 239Pu, 241Pu and a numerical method to convert these aggregate electron spectra into their corresponding antineutrino ones. In the present work we investigate quantitatively some of the basic assumptions and approximations used in the conversion method, studying first the compatibility between two recent approaches for calculating electron and antineutrino spectra. We then explore different possibilities for the disagreement between the measured Daya Bay and the Huber-Mueller antineutrino spectra, including the 238U contribution as well as the effective charge and the allowed shape assumption used in the conversion method. We observe that including a shape correction of about +6 % MeV-1 in conversion calculations can better describe the Daya Bay spectrum. Because of a lack of experimental data, this correction cannot be ruled out, concluding that in order to confirm the existence of the reactor neutrino anomaly, or even quantify it, precisely measured electron spectra for about 50 relevant fission products are needed. With the advent of new rare ion facilities, the measurement of shape factors for these nuclides, for many of which precise beta intensity data from TAGS experiments already exist, would be highly desirable.
Calculation of sound propagation in fibrous materials
DEFF Research Database (Denmark)
Tarnow, Viggo
1996-01-01
Calculations of attenuation and velocity of audible sound waves in glass wools are presented. The calculations use only the diameters of fibres and the mass density of glass wools as parameters. The calculations are compared with measurements.......Calculations of attenuation and velocity of audible sound waves in glass wools are presented. The calculations use only the diameters of fibres and the mass density of glass wools as parameters. The calculations are compared with measurements....
Clouvas, A; Antonopoulos-Domis, M; Silva, J
2000-01-01
The dose rate conversion factors D/sub CF/ (absorbed dose rate in air per unit activity per unit of soil mass, nGy h/sup -1/ per Bq kg/sup -1/) are calculated 1 m above ground for photon emitters of natural radionuclides uniformly distributed in the soil. Three Monte Carlo codes are used: 1) The MCNP code of Los Alamos; 2) The GEANT code of CERN; and 3) a Monte Carlo code developed in the Nuclear Technology Laboratory of the Aristotle University of Thessaloniki. The accuracy of the Monte Carlo results is tested by the comparison of the unscattered flux obtained by the three Monte Carlo codes with an independent straightforward calculation. All codes and particularly the MCNP calculate accurately the absorbed dose rate in air due to the unscattered radiation. For the total radiation (unscattered plus scattered) the D/sub CF/ values calculated from the three codes are in very good agreement between them. The comparison between these results and the results deduced previously by other authors indicates a good ag...
Torsional electric dipole moment functions calculated for HOOH and ClOOCl
McGrath, Mark P.
2013-03-01
The periodic torsional, electric dipole moment (EDM) functions μ(ϕ) = ∑m = 0pmcos (m + 1/2)ϕ, of the atmospherically significant molecules HOOH and ClOOCl, have been derived from calculations at the CCSD(T) (coupled-cluster singles and doubles model, plus a noniterative triples correction) level of electronic-structure theory with augmented, correlation-consistent basis sets extrapolated to the approximate complete basis set limit. The μ(ϕ) of HOOH, defined by {pm} = {3.0979, -0.0301, -0.0058} D, is used to calculate squared transition EDMs that compare well with those previously derived using the experimental torsional line intensities. The μ(ϕ) of ClOOCl, defined by μ(ϕ) = {1.1935, 0.1163, 0.1341, -0.0040, -0.0099} D, requires a longer Fourier expansion because, in the range of dihedral angles from the cis (ϕ = 0) to the trans (ϕ = π) transition structures, three inflection points are found for ClOOCl, but only one for HOOH. The permanent EDM calculated for HOOH, 1.754 D, is in close agreement with the value deduced from experiment. Compared to HOOH, the permanent EDM vector calculated for ClOOCl is directed analogously, but has a significantly smaller magnitude, 0.700 D.
The bending vibration response and approximate calculation of elastic cylindrical shell
Institute of Scientific and Technical Information of China (English)
CHEN Xiao-li; SHENG Mei-ping; HE Chen
2006-01-01
Useful structure characteristics of elastic cylindrical shells have led them to being widely applied in virtual projects ,so it is important to conduct vibration research on the shells and find it's a simpler corresponding compact calculation method. Utilising the input and transfer point mobility of a thin plate structure, a theoretical expression of the cylindrical shell's bending vibration responsewas deduced and numerical simulations were done to simplify the theoretical expression within an acceptable error margin, greatly reducing the amount of computations. Furthermore, whole vibration response distributions of the cylindrical shell were analyzed. It was found thathe vibration energy propagates in helical form under mono-frequency excitation, while under bandwidth frequency excitation, it attenuates around in term of fluctuation. The axial attenuation rate of the vibration energy is larger than the circumferential attenuation rate.
First-principle calculation of solar cell efficiency under incoherent illumination
Sarrazin, Michael; Deparis, Olivier
2013-01-01
Because of the temporal incoherence of sunlight, solar cells efficiency should depend on the degree of coherence of the incident light. However, numerical computation methods, which are used to optimize these devices, fundamentally consider fully coherent light. Hereafter, we show that the incoherent efficiency of solar cells can be easily analytically calculated. The incoherent efficiency is simply derived from the coherent one thanks to a convolution product with a function characterizing the incoherent light. Our approach is neither heuristic nor empiric but is deduced from first-principle, i.e. Maxwell's equations. Usually, in order to reproduce the incoherent behavior, statistical methods requiring a high number of numerical simulations are used. With our method, such approaches are not required. Our results are compared with those from previous works and good agreement is found.
Izumi, H; Adachi, T; Fujii, N; Matsuda, T; Nakamura, R; Tanaka, K; Urisu, A; Kurosawa, Y
1992-05-18
A cDNA clone of rice major allergenic protein (RAP) was isolated from a cDNA library of maturing rice seeds. The cDNA had an open reading frame (486 nucleotides) which coded a 162 amino acid residue polypeptide comprising a 27-residue signal peptide and a 135-residue mature protein of M(r) 14,764. The deduced amino acid sequence of RAP showed a considerable similarity to barley trypsin inhibitor [1983, J. Biol. Chem. 258, 7998-8003] and wheat alpha-amylase inhibitor [1981, Phytochemistry 20, 1781-1784].
Painless causality in defect calculations
Cheung, C; Cheung, Charlotte; Magueijo, Joao
1997-01-01
Topological defects must respect causality, a statement leading to restrictive constraints on the power spectrum of the total cosmological perturbations they induce. Causality constraints have for long been known to require the presence of an under-density in the surrounding matter compensating the defect network on large scales. This so-called compensation can never be neglected and significantly complicates calculations in defect scenarios, eg. computing cosmic microwave background fluctuations. A quick and dirty way to implement the compensation are the so-called compensation fudge factors. Here we derive the complete photon-baryon-CDM backreaction effects in defect scenarios. The fudge factor comes out as an algebraic identity and so we drop the negative qualifier ``fudge''. The compensation scale is computed and physically interpreted. Secondary backreaction effects exist, and neglecting them constitutes the well-defined approximation scheme within which one should consider compensation factor calculatio...
Dyscalculia and the Calculating Brain.
Rapin, Isabelle
2016-08-01
Dyscalculia, like dyslexia, affects some 5% of school-age children but has received much less investigative attention. In two thirds of affected children, dyscalculia is associated with another developmental disorder like dyslexia, attention-deficit disorder, anxiety disorder, visual and spatial disorder, or cultural deprivation. Infants, primates, some birds, and other animals are born with the innate ability, called subitizing, to tell at a glance whether small sets of scattered dots or other items differ by one or more item. This nonverbal approximate number system extends mostly to single digit sets as visual discrimination drops logarithmically to "many" with increasing numerosity (size effect) and crowding (distance effect). Preschoolers need several years and specific teaching to learn verbal names and visual symbols for numbers and school agers to understand their cardinality and ordinality and the invariance of their sequence (arithmetic number line) that enables calculation. This arithmetic linear line differs drastically from the nonlinear approximate number system mental number line that parallels the individual number-tuned neurons in the intraparietal sulcus in monkeys and overlying scalp distribution of discrete functional magnetic resonance imaging activations by number tasks in man. Calculation is a complex skill that activates both visual and spatial and visual and verbal networks. It is less strongly left lateralized than language, with approximate number system activation somewhat more right sided and exact number and arithmetic activation more left sided. Maturation and increasing number skill decrease associated widespread non-numerical brain activations that persist in some individuals with dyscalculia, which has no single, universal neurological cause or underlying mechanism in all affected individuals.
Halligan, Brian D; Ruotti, Victor; Twigger, Simon N; Greene, Andrew S
2005-07-01
One of the core activities of high-throughput proteomics is the identification of peptides from mass spectra. Some peptides can be identified using spectral matching programs like Sequest or Mascot, but many spectra do not produce high quality database matches. De novo peptide sequencing is an approach to determine partial peptide sequences for some of the unidentified spectra. A drawback of de novo peptide sequencing is that it produces a series of ordered and disordered sequence tags and mass tags rather than a complete, non-degenerate peptide amino acid sequence. This incomplete data is difficult to use in conventional search programs such as BLAST or FASTA. DeNovoID is a program that has been specifically designed to use degenerate amino acid sequence and mass data derived from MS experiments to search a peptide database. Since the algorithm employed depends on the amino acid composition of the peptide and not its sequence, DeNovoID does not have to consider all possible sequences, but rather a smaller number of compositions consistent with a spectrum. DeNovoID also uses a geometric indexing scheme that reduces the number of calculations required to determine the best peptide match in the database. DeNovoID is available at http://proteomics.mcw.edu/denovoid.
Institute of Scientific and Technical Information of China (English)
YU Jinhai; ZHOU Xinmin; Y. S. O'Reilly; ZHAO Lei; W. L. Griffin; WANG Rucheng; WANG Lijuan; CHEN Xiaomin
2005-01-01
The petrochemical as well as zircon U-Pb and Lu-Hf isotopic studies of granulite facies metamorphic rock from the Taoxi Group in eastern Nanling Range, Central Cathaysia indicate that its protolith is the sedimentary rock with low maturation index. The clastic materials are mostly from middle Neoproterozoic (~736 Ma) granitoid rocks with minor Neoarchaean and Paleoproterozoic rocks. The timing of this Neoproterozoic magmatism is in agreement with the second period of magmatism widespread surrounding the Yangtze Block. Hf isotopic data indicate that the Neoproterozoic granitoids resulted from the recycled Paleoproterozoic mantle-derived crustal materials. The sedimentary rock was deposited in Late Neoproterozoic Era, and carried into low crust in Early Paleozoic. The partial melting of the meta-sedimentary rock took place at about 480 Ma and subsequently granulite facies metamorphism occurred at ca. 443 Ma. The zircons forming during this time interval (Early Paleozoic) show large Hf isotope variations, and their -Hf(t) values increase from -13.2 to +2.36 with decreasing age, suggesting the injection of mantle-derived materials during partial melting and metamorphism processes in the Early Paleozoic. Calculation results show that this metamorphic rock, if evolved to Mesozoic, has similar isotopic composition to the nearby Mesozoic high Si peraluminous granites, implying that this kind of granulite facies metamorphic rock is probably the source material of some Mesozoic peraluminous granitoids in eastern Nanling Range.
Hanebuth, T. J.; Kudrass, H.; Linstädter, J.; Islam, B.; Zander, A. M.
2013-12-01
The densely populated low lying Ganges-Brahmaputra Delta is highly vulnerable to the global sea-level rise. In order to estimate the subsidence of the delta over historical time scales, we examined submerged salt-producing kiln sites in the coastal Sundarbans. These kilns were built just above the previous winterly spring high-tide level, but are currently located ~155 × 15 cm below the corresponding modern level. According to optically stimulated luminescence (OSL) dating, the kilns were ultimately fired ~300 years ago (1705 × 35 AD) and salt production was terminated abruptly by a catastrophic event (major cyclone), which affected the kiln sites at different levels and locations. Two particular buried mangrove root horizons 80 cm below this kiln level also indicate catastrophic scenarios (probably subsidence events related to a regional earthquake). AMS-14C ages measured on the charcoal layers at the kiln's bases and on these associated mangrove stump horizons support the OSL dates. Based on the respective elevations of these kiln and mangrove palaeo-horizons and on the ages, the 300-year-average rate of sinking of the outer delta is 5.2 × 1.2 mm/a, which includes 0.8 mm/a of eustatic sea-level rise over this historical period. Expecting further acceleration of the eustatic sea-level rise of up to 7 mm/a, we calculate a rise in relative sea level of up to 8.9 × 3.3 mm/a for the next few decased, which will dramatically aggravate the already present problematic situation. Only a prudently-managed control of sediment accretion will keep southern Bangladesh above the sea level. (Hanebuth et al., Geology, Sept 2013, doi: 10.1130/G34646.1.)
Yang, Changjun; Zhao, Biqiang; Zhu, Jie; Yue, Xinan; Wan, Weixing
2017-10-01
In this study we propose the combination of topside in-situ ion density data from the Communication/Navigation Outage Forecast System (C/NOFS) along with the electron density profile measurement from Constellation Observing System for Meteorology, Ionosphere & Climate (COSMIC) satellites Radio Occultation (RO) for studying the spatial and temporal variations of the ionospheric upper transition height (hT) and the oxygen ion (O+) density scale height. The latitudinal, local time and seasonal distributions of upper transition height show more consistency between hT re-calculated by the profile of the O+ using an α-Chapman function with linearly variable scale height and that determined from direct in-situ ion composition measurements, than with constant scale height and only the COSMIC data. The discrepancy in the values of hT between the C/NOFS measurement and that derived by the combination of COSMIC and C/NOFS satellites observations with variable scale height turns larger as the solar activity decreases, which suggests that the photochemistry and the electrodynamics of the equatorial ionosphere during the extreme solar minimum period produce abnormal structures in the vertical plasma distribution. The diurnal variation of scale heights (Hm) exhibits a minimum after sunrise and a maximum around noon near the geomagnetic equator. Further, the values of Hm exhibit a maximum in the summer hemisphere during daytime, whereas in the winter hemisphere the maximum is during night. Those features of Hm consistently indicate the prominent role of the vertical electromagnetic (E × B) drift in the equatorial ionosphere.
Directory of Open Access Journals (Sweden)
J. R. Taylor
Full Text Available The dynamic behaviour of the northern polar cap area is studied employing Northern Hemisphere electric potential patterns derived by the Assimilative Mapping of Ionospheric Electrodynamics (AMIE procedure. The rate of change in area of the polar cap, which can be defined as the region of magnetospheric field lines open to the interplanetary magnetic field (IMF, has been calculated during two intervals when the IMF had an approximately constant southward component (1100–2200 UT, 20 March 1990 and 1300–2100 UT, 21 March 1990. The estimates of the polar cap area are based on the approximation of the polar cap boundary by the flow reversal boundary. The change in the polar cap area is then compared to the predicted expansion rate based on a simple application of Faraday's Law. Furthermore, timings of magnetospheric substorms are also related to changes in the polar cap area. Once the convection electric field reconfigures following a southward turning of the IMF, the growth rate of the observed polar cap boundary is consistent with that predicted by Faraday's Law. A delay of typically 20 min to 50 min is observed between a substorm expansion phase onset and a reduction in the polar cap area. Such a delay is consistent with a synthesis between the near Earth neutral line and current disruption models of magnetospheric substorms in which the dipolarisation in the magnetotail may act as a trigger for reconnection. These delays may represent a propagation time between near geosynchronous orbit dipolarisation and subsequent reconnection further down tail. We estimate, from these delays, that the neutral X line occurs between ~35R_{E} and ~75R_{E} downstream in the tail.
CONDOR-CITVAP-MCNP calculation line description
Energy Technology Data Exchange (ETDEWEB)
Villarino, Eduardo Anibal [INVAP S.E., San Carlos de Bariloche (Argentina)
2002-07-01
A general description of the CONDOR-CITVAP-MCNP calculation line is given. This calculation line starts at cross section library and allows burnup dependent detailed calculation using MCNP. This calculation line is divided in two main methodologies: CONDOR-CITVAP that allows the 3-Dimensional core burnup calculation and MCNP that performs detailed transport calculations, both methodologies are coupled using the NDDUMP code. A short description of the used codes are given: CONDOR code performs the cell calculation, generating burnup dependent macroscopic cross section and burnup dependent numerical densities per material. CITVAP codes perform the burnup dependent core calculation, including the fuel management and calculates the burnup distribution per material. NDDUMP code generates materials burnup dependent numerical densities to be used by MCNP code. This paper presents a detailed description of the CONDOR-CITVAP-MCNP calculation line and a numerical comparison of the proposed methodology. (author)
Factors affecting calculation of L
Ciotola, Mark P.
2001-08-01
A detectable extraterrestrial civilization can be modeled as a series of successive regimes over time each of which is detectable for a certain proportion of its lifecycle. This methodology can be utilized to produce an estimate for L. Potential components of L include quantity of fossil fuel reserves, solar energy potential, quantity of regimes over time, lifecycle patterns of regimes, proportion of lifecycle regime is actually detectable, and downtime between regimes. Relationships between these components provide a means of calculating the lifetime of communicative species in a detectable state, L. An example of how these factors interact is provided, utilizing values that are reasonable given known astronomical data for components such as solar energy potential while existing knowledge about the terrestrial case is used as a baseline for other components including fossil fuel reserves, quantity of regimes over time, and lifecycle patterns of regimes, proportion of lifecycle regime is actually detectable, and gaps of time between regimes due to recovery from catastrophic war or resource exhaustion. A range of values is calculated for L when parameters are established for each component so as to determine the lowest and highest values of L. roadmap for SETI research at the SETI Institute for the next few decades. Three different approaches were identified. 1) Continue the radio search: build an affordable array incorporating consumer market technologies, expand the search frequency, and increase the target list to 100,000 stars. This array will also serve as a technology demonstration and enable the international radio astronomy community to realize an array that is a hundred times larger and capable (among other things) of searching a million stars. 2) Begin searches for very fast optical pulses from a million stars. 3) As Moore's Law delivers increased computational capacity, build an omni-directional sky survey array capable of detecting strong, transient
Energy Technology Data Exchange (ETDEWEB)
Nummela, S. E-mail: saara.nummela@phys.jyu.fi; Baumann, P.; Caurier, E.; Courtin, S.; Dessagne, P.; Holmlund, E.; Jokinen, A.; Knipper, A.; Le Scornet, G.; Mieh, C.; Nowacki, F.; Lyapin, L.G.; Oinonen, M.; Poirier, E.; Radivojevic, Z.; Ramdhane, M.; Trzaska, W.H.; Walter, G.; Aeystoe, J
2002-04-22
The first information on the level structure of the N=21 nuclei, {sup 35}Si and {sup 33}Mg, has been obtained by the beta decay study of {sup 35}Al and {sup 33}Na, produced by fragmentation of an UC target with 1.4 GeV protons at CERN/ISOLDE. The experimental technique involved {beta}-{gamma}, {beta}-{gamma}-{gamma}, and {beta}-n-{gamma} coincidences, neutron spectra being obtained by time of flight measurements. Gamma detection was made either using large Ge counters or small BaF{sub 2} scintillators (for lifetime measurements). In the case of the {sup 35}Al decay, (T{sub 1/2}=41.6(2.2) ms), a simple structure has been found for the level scheme of {sup 35}Si (Z=14, N=21) which has been interpreted with the level sequence : 7/2{sup -}, 3/2{sup -} and 3/2{sup +} corresponding respectively to the ground state and the states at 910 and 974 keV. The life-time of the 974 keV [T{sub 1/2}=5.9(6) ns] is found consistent with the proposed level scheme and multipolarities. The investigation of the N=21, very neutron rich isotones, has been carried on with the study of {sup 33}Mg resulting from the {sup 33}Na decay, (T{sub 1/2}=8.0(6) ms). In this case also, a level scheme could be obtained for the first time, with 5 bound states in {sup 32}Mg and {sup 31}Mg levels, populated in the 1n and 2n channels. These results are compared with sd-fp shell model calculations which give a fair account of the Gamow-Teller distribution and a reasonable explanation of the lowest levels with predominant contribution of 1p-1h and 2p-2h excitations.
Energy Technology Data Exchange (ETDEWEB)
Nakata, Hidehiko [Waseda Univ., Tokyo (Japan). Dept. of Physics; Tachibana, Takahiro; Yamada, Masami
1997-03-01
Recently the gross theory of nuclear {beta}-decay was refined for odd-odd nuclei. In this refinement, the effect of the selection rule of {beta}-transitions from the ground states of odd-odd nuclei to those of even-even nuclei was taken into account based on a statistical consideration. The transitions to the first 2{sup +} excited states in even-even nuclei were also taken into account according to the selection rule approximately. In that study, it was found that the transitions between 1{sup -} ground states of the odd-odd nuclei and 0{sup +} ground states of even-even nuclei, belonging to the first-forbidden transitions of rank 1, are strongly hindered. A reduction factor was introduced for the transitions to the ground states of even-even nuclei to take into account this hindrance. It was also found that the strength functions of the Gamow-Teller transitions obtained from the conventional gross theory are underestimated by a factor of about 3. In order to improve this underestimation, the Lorentz-type function was adopted for the one-particle strength function in the model instead of the hyperbolic-secant-type function. In the present study we have newly analyzed the experimental ft-values of odd-A nuclei, and found that the first-forbidden transitions of rank 1 are also considerably hindered between the ground states. Following the above refinement we have calculated the {beta}-ray spectra of some odd-odd short-lived fission products with the use of the refined gross theory. These results are compared not only with the experiments by Rudstam et al. but also with the conventional gross theory. (author)
Thermodynamic Calculations for Complex Chemical Mixtures
Mcbride, B. J.
1986-01-01
General computer program, CECTRP, developed for calculation of thermodynamic properties of complex mixtures with option to calculate transport properties of these mixtures. Free-energy minimization technique used in equilibrium calculation. Rigorous equations used in transport calculations. Program calculates equilibrium compositions and corresponding thermodynamic and transport properties of mixtures. CECTRP accommodates up to 24 reactants, 20 elements, and 600 products, 400 of which are condensed. Written in FORTRAN IV for any large computer system.
Yunus, Abdul S; Govindarajan, Dhanasekaran; Huang, Zhuhui; Samal, Siba K
2003-05-01
We report here the nucleotide and deduced amino acid (aa) sequences of the small hydrophobic (SH) gene of the avian pneumovirus strain Colorado (APV/CO). The SH gene of APV/CO is 628 nucleotides in length from gene-start to gene-end. The longest ORF of the SH gene encoded a protein of 177 aas in length. Comparison of the deduced aa sequence of the SH protein of APV/CO with the corresponding published sequences of other members of genera metapneumovirus showed 28% identity with the newly discovered human metapneumovirus (hMPV), but no discernable identity with the APV subgroup A or B. Collectively, this data supports the hypothesis that: (i) APV/CO is distinct from European APV subgroups and belongs to the novel subgroup APV/C (APV/US); (ii) APV/CO is more closely related to hMPV, a mammalian metapneumovirus, than to either APV subgroup A or B. The SH gene of APV/CO was cloned using a genomic walk strategy which initiated cDNA synthesis from genomic RNA that traversed the genes in the order 3'-M-F-M2-SH-G-5', thus confirming that gene-order of APV/CO conforms in the genus Metapneumovirus. We also provide the sequences of transcription-signals and the M-F, F-M2, M2-SH and SH-G intergenic regions of APV/CO.
Selfconsistent calculations for hyperdeformed nuclei
Energy Technology Data Exchange (ETDEWEB)
Molique, H.; Dobaczewski, J.; Dudek, J.; Luo, W.D. [Universite Louis Pasteur, Strasbourg (France)
1996-12-31
Properties of the hyperdeformed nuclei in the A {approximately} 170 mass range are re-examined using the self-consistent Hartree-Fock method with the SOP parametrization. A comparison with the previous predictions that were based on a non-selfconsistent approach is made. The existence of the {open_quotes}hyper-deformed shell closures{close_quotes} at the proton and neutron numbers Z=70 and N=100 and their very weak dependence on the rotational frequency is suggested; the corresponding single-particle energy gaps are predicted to play a role similar to that of the Z=66 and N=86 gaps in the super-deformed nuclei of the A {approximately} 150 mass range. Selfconsistent calculations suggest also that the A {approximately} 170 hyperdeformed structures have neglegible mass asymmetry in their shapes. Very importantly for the experimental studies, both the fission barriers and the {open_quotes}inner{close_quotes} barriers (that separate the hyperdeformed structures from those with smaller deformations) are predicted to be relatively high, up to the factor of {approximately}2 higher than the corresponding ones in the {sup 152}Dy superdeformed nucleus used as a reference.
RTU Comparison Calculator Enhancement Plan
Energy Technology Data Exchange (ETDEWEB)
Miller, James D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Weimin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Katipamula, Srinivas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2015-07-01
Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy and cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.
RTU Comparison Calculator Enhancement Plan
Energy Technology Data Exchange (ETDEWEB)
Miller, James D.; Wang, Weimin; Katipamula, Srinivas
2014-03-31
Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy and cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.
RTU Comparison Calculator Enhancement Plan
Energy Technology Data Exchange (ETDEWEB)
Miller, James D.; Wang, Weimin; Katipamula, Srinivas
2014-03-31
Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy and cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.
Directory of Open Access Journals (Sweden)
Hayashizaki Yoshihide
2009-06-01
Full Text Available Abstract Background Wheat is an allopolyploid plant that harbors a huge, complex genome. Therefore, accumulation of expressed sequence tags (ESTs for wheat is becoming particularly important for functional genomics and molecular breeding. We prepared a comprehensive collection of ESTs from the various tissues that develop during the wheat life cycle and from tissues subjected to stress. We also examined their expression profiles in silico. As full-length cDNAs are indispensable to certify the collected ESTs and annotate the genes in the wheat genome, we performed a systematic survey and sequencing of the full-length cDNA clones. This sequence information is a valuable genetic resource for functional genomics and will enable carrying out comparative genomics in cereals. Results As part of the functional genomics and development of genomic wheat resources, we have generated a collection of full-length cDNAs from common wheat. By grouping the ESTs of recombinant clones randomly selected from the full-length cDNA library, we were able to sequence 6,162 independent clones with high accuracy. About 10% of the clones were wheat-unique genes, without any counterparts within the DNA database. Wheat clones that showed high homology to those of rice were selected in order to investigate their expression patterns in various tissues throughout the wheat life cycle and in response to abiotic-stress treatments. To assess the variability of genes that have evolved differently in wheat and rice, we calculated the substitution rate (Ka/Ks of the counterparts in wheat and rice. Genes that were preferentially expressed in certain tissues or treatments had higher Ka/Ks values than those in other tissues and treatments, which suggests that the genes with the higher variability expressed in these tissues is under adaptive selection. Conclusion We have generated a high-quality full-length cDNA resource for common wheat, which is essential for continuation of the
Directory of Open Access Journals (Sweden)
Gouda Mona M.
2016-01-01
Full Text Available A direct analytical mathematical method is introduced to calculate the efficiency of gamma ray cylindrical detectors. The efficiency expression is deduced through a straightforward mathematical approach. The presented method is based on the accurate analytical calculation of the average path length covered by the photon within the detector's active volume, effective solid angle, and the efficiency transfer method in an integral form, so as to obtain a simple formula for the detection efficiency. In addition, the self-attenuation coefficient of the source matrix, the attenuation factors of the source container (with a radius smaller than the detector radius and the detector housing materials are also treated by calculating the average path length within these materials. 152Eu aqueous radioactive sources covering the energy range from 121 keV to 1408 keV were used. Remarkable agreement between the measured and the calculated efficiencies was achieved, with discrepancies less than 6 %.
Institute of Scientific and Technical Information of China (English)
Wang Honggang; Wu Fengliang
2011-01-01
The control equations of gas concentration field in gob areas with a known velocity field are partial differential equations with variable coefficients, whose traditional mathematical calculation methods are very complex. A numerical simulation method can be used to calculate the gas concentration field, but it also needs considerable amounts of computer resources and the relations of gas concentration at different points of the gob area are undefined. Based on the model of stream tubes, the conservation equations of mass and gas components within the stream tube are used to deduce the equations of a gas concentration field in a gob area with a known velocity field. This method of calculation of a gas concentration field is applied in a gob area with a U-type ventilation working face, which suggests that this new method has the virtue of exact calculations is simple to operate and has a clear physical interpretation.
Ayma, D; Lichanot, A
1998-01-01
Compton profiles, polarizabilities and related functions of diamond and cubic boron nitride have been investigated within the Hartree-Fock approximation and the density functional theory, calculated within the local density approximation and generalized gradient approximation, but without any explicit correlation correction for the Compton profiles. The correlation part already included in the standard uncorrected density functional theory is deduced from the comparison of the two types of calculation. The Compton profile and reciprocal-form-factor anisotropies, polarizability, dielectric constant and energy loss function of the two compounds are compared at the same level of accuracy. These properties are very close in spite of the rather different chemical bonds due to the charge transfer occurring in cubic boron nitride and gaps. (author)
Energy Technology Data Exchange (ETDEWEB)
Masrour, R., E-mail: rachidmasrour@hotmail.com [Laboratory of Materials, Processes, Environment and Quality, Cady Ayyed University, National School of Applied Sciences, 63 46000, Safi (Morocco); LMPHE (URAC 12), Faculty of Science, Mohammed V-Agdal University, Rabat (Morocco); Hlil, E.K. [Institut Néel, CNRS et Université Joseph Fourier, BP 166, F-38042 Grenoble Cedex 9 (France); Hamedoun, M. [Institute of Nanomaterials and Nanotechnologies, MAScIR, Rabat (Morocco); Benyoussef, A. [LMPHE (URAC 12), Faculty of Science, Mohammed V-Agdal University, Rabat (Morocco); Institute of Nanomaterials and Nanotechnologies, MAScIR, Rabat (Morocco); Hassan II Academy of Science and Technology, Rabat (Morocco); Boutahar, A.; Lassri, H. [LPMMAT, Université Hassan II-Casablanca, Faculté des Sciences, BP 5366 Maârif (Morocco)
2015-11-01
The self-consistent ab initio calculations, based on DFT (Density Functional Theory) approach and using FLAPW (Full potential Linear Augmented Plane Wave) method, are performed to investigate both electronic and magnetic properties of the Mn{sub 2}Au. Polarized spin and spin–orbit coupling are included in calculations within the framework of the antiferromagnetic state between two adjacent Mn plans. Magnetic moment considered to lie along (110) axes are computed. Obtained data from ab initio calculations are used as input for the high temperature series expansions (HTSEs) calculations to compute other magnetic parameters. The exchange interactions between the magnetic atoms Mn–Mn in Mn{sub 2}Au are given by using the experiment results and the mean field theory. The High Temperature Series Expansions (HTSEs) of the magnetic susceptibility with the magnetic moments in Mn{sub 2}Au (m{sub Mn}) is given up to tenth order series in, 1/k{sub B}T. The Néel temperature T{sub N} is obtained by HTSEs combined with the Padé approximant method. The critical exponent associated with the magnetic susceptibility is deduced as well. - Highlights: • The both electronic and magnetic properties of the Mn{sub 2}Au are studied. • The exchange interactions between the magnetic atoms Mn–Mn in Mn{sub 2}Au are given. • The Néel temperature T{sub N} of Mn{sub 2}Au is obtained by HTSEs method. • The critical exponent associated with the magnetic susceptibility is deduced.
Institute of Scientific and Technical Information of China (English)
Yuan Xiaoming; Sun Jing; Sun Rui
2006-01-01
An error analysis of the dynamic shear modulus of stiff specimens from tests performed by a new resonant column device developed by the Institute of Engineering Mechanics, China was conducted. A modified approach for calculating the dynamic shear modulus of the stiff specimens is presented. The error formula of the tests was deduced and parameters that impact the accuracy of the test were identified. Using six steel specimens with known standard stiffness as a base, a revised dynamic shear modulus calculation for stiff specimens was formulated by comparing three of the models.The maximum error between the test results and the calculated results shown by curves from both the free-vibration and the resonant-vibration tests is less than 6%. The free-vibration and resonant-vibration tests for three types of stiff samples with a known modulus indicate that the maximum deviation between the actual and the tested value using the modified approach were less than 10%. As a result, the modified approach presented here is shown to be reliable and the new device can be used for testing dynamic shear modulus of any stiff materials at low shear strain levels
Calculation method on shape finding of self-anchored suspension bridge with spatial cables
Institute of Scientific and Technical Information of China (English)
Yan HAN; Zhengqing CHEN; Shidong LUO; Shankui YANG
2009-01-01
Based on the spatial model, a reliable and accurate calculation method on the shape finding of self anchored suspension bridge with spatial cables was studiedin this paper. On the principle that the shape of the main cables between hangers is catenary, the iteration method of calculating the shapes of the spatial main cables under the load of hanger forces was deduced. The reasonable position of the saddle was determined according to the shape and the theoretical joint point of the main cables. The shapes of the main cables at completed cable stage werecalculated based on the unchanging principle of the zero-stress lengths of the main cables. By using a numerical method combining with the finite element method, one self-anchored suspension bridge with spatial cables was analyzed. The zero-stress length of the main cables, the position of the saddle, and the pre-offsetting of the saddle of the self-anchored suspension bridge were given. The reasonable shapes of the main cables at bridge completion stage and completed cable stage were presented. The results show that the shape-finding calculation method is effective and reliable.
CHP Energy and Emissions Savings Calculator
Download the CHP Emissions Calculator, a tool that calculates the difference between the anticipated carbon dioxide, methane, nitrous oxide, sulfur dioxide, and nitrogen oxide emissions from a CHP system to those of a separate heat and power system.
Dynamics Calculation of Travel Wave Tube
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
During the dynamics calculating of the travel tube, we must obtain the field map in the tube. The field map can be affected by not only the beam loading, but also the attenuation coefficient. The calculation of the attenuation coefficient
A New Approach for Calculating Vacuum Susceptibility
Institute of Scientific and Technical Information of China (English)
宗红石; 平加伦; 顾建中
2004-01-01
Based on the Dyson-Schwinger approach, we propose a new method for calculating vacuum susceptibilities. As an example, the vector vacuum susceptibility is calculated. A comparison with the results of the previous approaches is presented.
76 FR 71431 - Civil Penalty Calculation Methodology
2011-11-17
... TRANSPORTATION Federal Motor Carrier Safety Administration Civil Penalty Calculation Methodology AGENCY: Federal... its civil penalty methodology. Part of this evaluation includes a forthcoming explanation of the... methodology for calculation of certain civil penalties. To induce compliance with federal regulations,...
Pressure Vessel Calculations for VVER-440 Reactors
Hordósy, G.; Hegyi, Gy.; Keresztúri, A.; Maráczy, Cs.; Temesvári, E.; Vértes, P.; Zsolnay, É.
2003-06-01
Monte Carlo calculations were performed for a selected cycle of the Paks NPP Unit II to test a computational model. In the model the source term was calculated by the core design code KARATE and the neutron transport calculations were performed by the MCNP. Different forms of the source specification were examined. The calculated results were compared with measurements and in most cases fairly good agreement was found.
Mathematical Creative Activity and the Graphic Calculator
Duda, Janina
2011-01-01
Teaching mathematics using graphic calculators has been an issue of didactic discussions for years. Finding ways in which graphic calculators can enrich the development process of creative activity in mathematically gifted students between the ages of 16-17 is the focus of this article. Research was conducted using graphic calculators with…
47 CFR 1.1623 - Probability calculation.
2010-10-01
... 47 Telecommunication 1 2010-10-01 2010-10-01 false Probability calculation. 1.1623 Section 1.1623... Mass Media Services General Procedures § 1.1623 Probability calculation. (a) All calculations shall be computed to no less than three significant digits. Probabilities will be truncated to the number of...
Status Report of NNLO QCD Calculations
Klasen, M
2005-01-01
We review recent progress in next-to-next-to-leading order (NNLO) perturbative QCD calculations with special emphasis on results ready for phenomenological applications. Important examples are new results on structure functions and jet or Higgs boson production. In addition, we describe new calculational techniques based on twistors and their potential for efficient calculations of multiparticle amplitudes.
A general formalism for phase space calculations
Norbury, John W.; Deutchman, Philip A.; Townsend, Lawrence W.; Cucinotta, Francis A.
1988-01-01
General formulas for calculating the interactions of galactic cosmic rays with target nuclei are presented. Methods for calculating the appropriate normalization volume elements and phase space factors are presented. Particular emphasis is placed on obtaining correct phase space factors for 2-, and 3-body final states. Calculations for both Lorentz-invariant and noninvariant phase space are presented.
Decimals, Denominators, Demons, Calculators, and Connections
Sparrow, Len; Swan, Paul
2005-01-01
The authors provide activities for overcoming some fraction misconceptions using calculators specially designed for learners in primary years. The writers advocate use of the calculator as a way to engage children in thinking about mathematics. By engaging with a calculator as part of mathematics learning, children are learning about and using the…
Energy Technology Data Exchange (ETDEWEB)
Birkhan, Jonny Hubertus
2016-07-01
only up to an excitation energy of 60 MeV. Taking into account the excitation energy range from E{sub x}=10 MeV to E{sub x}=60 MeV the polarisability of the nucleus {sup 48}Ca was estimated to be α{sub D}=(2.09±0.02) fm{sup 3}. This result deviates significantly from a theoretical prediction of α{sub D}=(2.31±0.09) fm{sup 3} based on the energy density functional theory. The result of this work could further constrain the range of the parameters of the nuclear models and might give new insights on the neutron skin thickness of {sup 48}Ca as far as a theoretical prediction for the correlation between the polarisability and neutron skin thickness is available especially for the energy region investigated in this work. In the nucleus {sup 48}Ca, almost the full experimentally accessible spin-M1 strength is exhausted by a single spin-flip transition. The corresponding state is the prominent 1{sup +}-state at E{sub x}=10.22 MeV. The configuration of the nucleus {sup 48}Ca leads to nearly pure spin-flip transitions of the neutrons. In this case the isoscalar transition matrix element is as large as the isovector one. This means that the nucleus {sup 48}Ca is a reference case whereas the nucleus {sup 208}Pb is another one because its isoscalar and isovector M1 strength is well separated. The extraction of the total electromagnetic M1 strength was based on a method that had been successfully applied to Gamow-Teller transitions in other analyses in the framework of a distorted wave impulse approximation. This method allows to calculate the strength from the measured isovector cross section at θ{sub CM}=0 mainly by a single conversion factor, the so-called ''unit cross section''. The method was used for the analysis of this work assuming that isospin symmetry is given for isobars and that the unit cross section is the same for isovector spin-M1 excitations as well as for the excitations of analogue states. The problem was to extract the isovector part of
Energy Technology Data Exchange (ETDEWEB)
Birkhan, Jonny Hubertus
2016-07-01
only up to an excitation energy of 60 MeV. Taking into account the excitation energy range from E{sub x}=10 MeV to E{sub x}=60 MeV the polarisability of the nucleus {sup 48}Ca was estimated to be α{sub D}=(2.09±0.02) fm{sup 3}. This result deviates significantly from a theoretical prediction of α{sub D}=(2.31±0.09) fm{sup 3} based on the energy density functional theory. The result of this work could further constrain the range of the parameters of the nuclear models and might give new insights on the neutron skin thickness of {sup 48}Ca as far as a theoretical prediction for the correlation between the polarisability and neutron skin thickness is available especially for the energy region investigated in this work. In the nucleus {sup 48}Ca, almost the full experimentally accessible spin-M1 strength is exhausted by a single spin-flip transition. The corresponding state is the prominent 1{sup +}-state at E{sub x}=10.22 MeV. The configuration of the nucleus {sup 48}Ca leads to nearly pure spin-flip transitions of the neutrons. In this case the isoscalar transition matrix element is as large as the isovector one. This means that the nucleus {sup 48}Ca is a reference case whereas the nucleus {sup 208}Pb is another one because its isoscalar and isovector M1 strength is well separated. The extraction of the total electromagnetic M1 strength was based on a method that had been successfully applied to Gamow-Teller transitions in other analyses in the framework of a distorted wave impulse approximation. This method allows to calculate the strength from the measured isovector cross section at θ{sub CM}=0 mainly by a single conversion factor, the so-called ''unit cross section''. The method was used for the analysis of this work assuming that isospin symmetry is given for isobars and that the unit cross section is the same for isovector spin-M1 excitations as well as for the excitations of analogue states. The problem was to extract the isovector part of
A simple model for calculating the bulk modulus of the mixed ionic crystal: NH4Cl1−xBr
Indian Academy of Sciences (India)
Vassiliki Katsika-Tsigourakou
2011-10-01
The ammonium halides are an interesting systems because of their polymorphism and the possible internal rotation of the ammonium ion. The static properties of the mixed ionic crystal NH4Cl1−Br have been recently investigated, using the three-body potential model (TDPM) by applying Vegard’s law. Here, by using a simple theoretical model, we estimate the bulk modulus of the alloys NH4Cl1−Br, in terms of the bulk modulus of the end members alone. The calculated values are comparable to those deduced from the three-body potential model (TDPM) by applying Vegard’s law.
Institute of Scientific and Technical Information of China (English)
李俊昌; 马琨; 樊则宾
2002-01-01
The vertical excitation axial-flux kilowatt CO2 laser is an equipment widely used in the high-power laser heat treatment industrial applications. The experimental measurements indicate that the power density distribution of laser beam is generally of ring distribution with a sunken at the center, therefore the laser beam cannot be simply regarded as base mode Gaussian beam. In this paper, such laser beam is regarded as the non-interference superposition of TEM00 and TEM01 mode beams, the method to determine the simulation parameters is discussed, and the relevant heat effect calculation equation is deduced.
Yin, Gang; Zhang, Yingtang; Mi, Songlin; Fan, Hongbo; Li, Zhining
2016-11-01
To obtain accurate magnetic gradient tensor data, a fast and robust calculation method based on regularized method in frequency domain was proposed. Using the potential field theory, the transform formula in frequency domain was deduced in order to calculate the magnetic gradient tensor from the pre-existing total magnetic anomaly data. By analyzing the filter characteristics of the Vertical vector transform operator (VVTO) and Gradient tensor transform operator (GTTO), we proved that the conventional transform process was unstable which would zoom in the high-frequency part of the data in which measuring noise locate. Due to the existing unstable problem that led to a low signal-to-noise (SNR) for the calculated result, we introduced regularized method in this paper. By selecting the optimum regularization parameters of different transform phases using the C-norm approach, the high frequency noise was restrained and the SNR was improved effectively. Numerical analysis demonstrates that most value and characteristics of the calculated data by the proposed method compare favorably with reference magnetic gradient tensor data. In addition, calculated magnetic gradient tensor components form real aeromagnetic survey provided better resolution of the magnetic sources and original profile.
Institute of Scientific and Technical Information of China (English)
邹振兴; 邹蓓尼
2014-01-01
该文叙述了离心式机械振动台的工作原理，提出了计算思路和方法；推导了其计算公式；并根据工程的实际情况，把复杂的计算公式，简化成代数运算式。%This paper describes the working principle of centrifugal mechanic vibrators, and proposes its calculation ideas and methods; and deduces its formula. Based on the actual situation of the project, it simplifies the complicated calculation formula into algebraic expression.
Microscopic Calculations of 240Pu Fission
Energy Technology Data Exchange (ETDEWEB)
Younes, W; Gogny, D
2007-09-11
Hartree-Fock-Bogoliubov calculations have been performed with the Gogny finite-range effective interaction for {sup 240}Pu out to scission, using a new code developed at LLNL. A first set of calculations was performed with constrained quadrupole moment along the path of most probable fission, assuming axial symmetry but allowing for the spontaneous breaking of reflection symmetry of the nucleus. At a quadrupole moment of 345 b, the nucleus was found to spontaneously scission into two fragments. A second set of calculations, with all nuclear moments up to hexadecapole constrained, was performed to approach the scission configuration in a controlled manner. Calculated energies, moments, and representative plots of the total nuclear density are shown. The present calculations serve as a proof-of-principle, a blueprint, and starting-point solutions for a planned series of more comprehensive calculations to map out a large set of scission configurations, and the associated fission-fragment properties.
Thermal QRPA with Skyrme interactions and supernova neutral-current neutrino-nucleus reactions
Dzhioev, Alan A; Martínez-Pinedo, G; Wambach, J; Stoyanov, Ch
2016-01-01
The Thermal Quasiparticle Random-Phase Approximation is combined with the Skyrme energy density functional method (Skyrme-TQRPA) to study the response of a hot nucleus to an external perturbation. For the sample nuclei, $^{56}$Fe and $^{82}$Ge, the Skyrme-TQRPA is applied to analyze thermal effects on the strength function of charge-neutral Gamow-Teller transitions which dominate neutrino-nucleus reactions at $E_\
Measurement of Angular Correlations in the Decay of Polarized Neutrons
DEFF Research Database (Denmark)
Christensen, Carl Jørgen; Krohn, V.E.; Ringo, G.R.
1970-01-01
The electron-momentum-neutron-spin correlation coefficient was found to be A=-0.115±0.008, and the antineutrino-momentum-neutron-spin correlation coefficient was found to be B=1.00±0.05. The value of A leads to |GA/GV|=1.26±0.02 for the ratio of Gamow-Teller-to-Fermi coupling constants in β decay...
The Ga-71(He-3, t) reaction and the low-energy neutrino response
Frekers, D.; Ejiri, H.; Akimune, H.; Adachi, T.; Bilgier, B.; Brown, B. A.; Cleveland, B. T.; Fujita, H.; Fujita, Y.; Fujiwara, M.; Ganioglu, E.; Gavrin, V. N.; Grewe, E. -W.; Guess, C. J.; Harakeh, M. N.; Hatanaka, K.; Hodak, R.; Holl, M.; Iwamoto, C.; Khai, N. T.; Kozer, H. C.; Lennarz, A.; Okamoto, A.; Okamura, H.; Povinec, P. P.; Puppe, P.; Simkovic, F.; Susoy, G.; Suzuki, T.; Tamii, A.; Thies, J. H.; Van de Walle, J.; Zegers, R. G. T.
2011-01-01
A Ga-71(He-3,t)Ge-71 charge-exchange experiment was performed to extract with high precision the Gamow-Teller (GT) transition strengths to the three lowest-lying states in Ge-71, i.e., the ground state (1/2(-)), the 175 keV (5/2(-)) and the 500 key (3/2(-)) excited states. These are the relevant sta
Systematic comparison of ISOLDE-SC yields with calculated in-target production rates
Energy Technology Data Exchange (ETDEWEB)
Lukic, S.; Gevaert, F.; Kelic, A.; Ricciardi, M.V.; Schmidt, K.H.; Yordanov, O.
2006-02-15
Recently, a series of dedicated inverse-kinematics experiments performed at GSI, Darmstadt, has brought an important progress in our understanding of proton and heavy-ion induced reactions at relativistic energies. The nuclear reaction code ABRABLA that has been developed and benchmarked against the results of these experiments has been used to calculate nuclide production cross sections at different energies and with different targets and beams. These calculations are used to estimate nuclide production rates by protons in thick targets, taking into account the energy loss and the attenuation of the proton beam in the target, as well as the low-energy fission induced by the secondary neutrons. The results are compared to the yields of isotopes of various elements obtained from different targets at CERN-ISOLDE with 600 MeV protons, and the overall extraction efficiencies are deduced. The dependence of these extraction efficiencies on the nuclide half-life is found to follow a simple pattern in many different cases. A simple function is proposed to parameterize this behavior in a way that quantifies the essential properties of the extraction efficiency for the element and the target - ion-source system in question. (orig.)
Test of 600 and 750 MeV NN matrix on elastic scattering Glauber model calculations
Brissaud, I.
1980-09-01
The 600 and 750 MeV proton nucleus elastic scattering cross section and polarization calculations have been performed in the framework of the Glauber model to test the pp and pn scattering amplitudes deduced from a phase shift analysis by Bystricky, Lechanoine and Lehar. It is well known that up to now we do not possess a non-phenomenological NN scattering matrix at intermediate energies. However proton-nucleus scattering analyses are used to extract information about short range correlations1), Δ resonance2) or pion condensation presences)... etc. Most scattering calculations made at these energies have been done with phenomenological NN amplitudes having a gaussian q-dependence 10050_2005_Article_BF01438168_TeX2GIFE1.gif A(q) = {kσ }/{4π }(α + i) e^{ - β ^2 q^2 /2} and 10050_2005_Article_BF01438168_TeX2GIFE2.gif C(q) = {kσ }/{4π }iq(α + i) D_e - β ^2 q^2 /2 K and σ being respectively the projectile momentum and the total pN total cross section. The parameters α, β and D are badly known and are adjusted by fitting some specific reactions as p+4He elastic scattering4). Even when these amplitudes provide good fits to the data, our understanding of the dynamics of the scattering remains obscure.
Status of lattice field theory calculations
Energy Technology Data Exchange (ETDEWEB)
Sharpe, S.R.
1990-01-01
This report briefly discusses the following topics: overview of all present calculation; reliability criteria for quenched calculation; quenched versus full QCD, and difficulties facing full QCD; results for the quenched pion wavefunction''; results for the quenched hadron spectrum; results for quenched B{sub K}; A new method for calculating the surface tension; the non-pertubative upper bound on the Higgs mass; and toward the TERAFLOP machine.
Calculation of the Moments of Polygons.
1987-06-01
2.1) VowUK-1N0+IDIO TUUNTKPlNO.YKNO C Calculate AREA YKXK-YKPIND*IKNO-YKNO*XKP1NO AIKA-hEEA4YKXX C Calculate ACEIT ACENT (1)- ACEIT ( 1) VSUNI4TKIK... ACEIT (2) -ACENT(2) .VSUNYKXK C Calculate SECHON 3ECNON (1) -SCNON( 1) TKXK*(XX~PIdO*VSUNXKKO**2) SECNO(2) -SEn N(2) .yrf* (XKP114*YKP1MO.XKO*YXO+VB1hi
Axial force calculation of passive magnetic bearing
National Research Council Canada - National Science Library
Vučković Ana N; Raičević Nebojša B; Ilić Saša S; Aleksić Slavoljub R; Perić Mirjana T
2014-01-01
.... Configuration like this one resembles the one passive magnetic bearing has. Force calculation is performed using semi analytical approach based on fictitious magnetization charges and discretization technique...
Pile Load Capacity – Calculation Methods
Directory of Open Access Journals (Sweden)
Wrana Bogumił
2015-12-01
Full Text Available The article is a review of the current problems of the foundation pile capacity calculations. The article considers the main principles of pile capacity calculations presented in Eurocode 7 and other methods with adequate explanations. Two main methods are presented: α – method used to calculate the short-term load capacity of piles in cohesive soils and β – method used to calculate the long-term load capacity of piles in both cohesive and cohesionless soils. Moreover, methods based on cone CPTu result are presented as well as the pile capacity problem based on static tests.
MATNORM: Calculating NORM using composition matrices
Pruseth, Kamal L.
2009-09-01
This paper discusses the implementation of an entirely new set of formulas to calculate the CIPW norm. MATNORM does not involve any sophisticated programming skill and has been developed using Microsoft Excel spreadsheet formulas. These formulas are easy to understand and a mere knowledge of the if-then-else construct in MS-Excel is sufficient to implement the whole calculation scheme outlined below. The sequence of calculation used here differs from that of the standard CIPW norm calculation, but the results are very similar. The use of MS-Excel macro programming and other high-level programming languages has been deliberately avoided for simplicity.
Surface Tension Calculation of Undercooled Alloys
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Based on the Butler equation and extrapolated thermodynamic data of undercooled alloys from those of liquid stable alloys, a method for surface tension calculation of undercooled alloys is proposed. The surface tensions of liquid stable and undercooled Ni-Cu (xNi=0.42) and Ni-Fe (xNi=0.3 and 0.7) alloys are calculated using STCBE (Surface Tension Calculation based on Butler Equation) program. The agreement between calculated values and experimental data is good enough, and the temperature dependence of the surface tension can be reasonable down to 150-200 K under the liquid temperature of the alloys.
Modern Feynman Diagrammatic One-Loop Calculations
Reiter, Thomas; Greiner, Nicolas; Guffanti, Alberto; Guillet, Jean-Philippe; Heinrich, Gudrun; Karg, Stefan; Kauer, Nikolas; Kleinschmidt, Tobias; Koch-Janusz, Maciej; Luisoni, Gionata; Mastrolia, Pierpaolo; Ossola, Giovanni; Pilon, Eric; Rodgers, Mark; Tramontano, Francesco; Wigmore, Ioan
2010-01-01
In this talk we present techniques for calculating one-loop amplitudes for multi-leg processes using Feynman diagrammatic methods in a semi-algebraic context. Our approach combines the advantages of the different methods allowing for a fast evaluation of the amplitude while monitoring the numerical stability of the calculation. In phase space regions close to singular kinematics we use a method avoiding spurious Gram determinants in the calculation. As an application of our approach we report on the status of the calculation of the amplitude for the process $pp\\to b\\bar{b}b\\bar{b}+X$.
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
It is difficult to identify the source(s) of mixed oils from multiple source rocks, and in particular the relative contribution of each source rock. Artificial mixing experiments using typical crude oils and ratios of different biomarkers show that the relative contribution changes are non-linear when two oils with different concentrations of biomarkers mix with each other. This may result in an incorrect conclusion if ratios of biomarkers and a simple binary linear equation are used to calculate the contribution proportion of each end-member to the mixed oil. The changes of biomarker ratios with the mixing proportion of end-member oils in the trinal mixing model are more complex than in the binary mixing model. When four or more oils mix, the contribution proportion of each end-member oil to the mixed oil cannot be calculated using biomarker ratios and a simple formula. Artificial mixing experiments on typical oils reveal that the absolute concentrations of biomarkers in the mixed oil cause a linear change with mixing proportion of each end-member. Mathematical inferences verify such linear changes. Some of the mathematical calculation methods using the absolute concentrations or ratios of biomarkers to quantitatively determine the proportion of each end-member in the mixed oils are deduced from the results of artificial experiments and by theoretical inference. Ratio of two biomarker compounds changes as a hyperbola with the mixing proportion in the binary mixing model,as a hyperboloid in the trinal mixing model, and as a hypersurface when mixing more than three endmembers. The mixing proportion of each end-member can be quantitatively determined with these mathematical models, using the absolute concentrations and the ratios of biomarkers. The mathematical calculation model is more economical, convenient, accurate and reliable than conventional artificial mixing methods.
Energy Technology Data Exchange (ETDEWEB)
Poyet, M
2005-07-01
Our work is dedicated to the assessment of the heat released in the Jet tokamak divertor tiles. We have performed the computation of the heat flux from temperature data collected by thermo-couples through a 1 dimensional linear model. This method has implied solving an inverse problem whose matrix is singular, we have succeeded in using Tikhonov's regularization technique. Then we have compared these values of the heat flux with those deduced from infra-red measurements. Infra-red measurements are impaired by the deposition of particles on the surface. Both methods give unrealistic negative values at the end of the plasma discharge. The use of a non-linear 1-dimensional model that would allow the diffusion coefficient to vary is expected to improve the calculation. (A.C.)
Directory of Open Access Journals (Sweden)
R. Stübi
2009-07-01
Full Text Available We present ozone measurements of the Global Atmospheric Sampling Program (GASP performed from four commercial and one research aircraft in the late 1970s to compare them with respective measurements of the ongoing MOZAIC project. Multi-annual averages of UT/LS ozone were built using the aircraft data sets (1975–1979 and 1994–2001, and long-term changes between the 1970s and 1990s were derived by comparison. The data were binned relative to the dynamical tropopause to separate between UT and LS air masses. LS data were analysed using equivalent latitudes. In the UT, pronounced increases of 20–40% are found over the Middle East and South Asia in the spring and summer seasons. Increases are also found over Japan, Europe, and the eastern parts of the United States depending on season. LS ozone over northern mid- and high latitudes was found to be lower in the 1990s compared to the 1970s in all seasons of the year. In addition, a comparison with long-term changes deduced from ozonesondes is presented. The early 1970s European Brewer-Mast (BM sonde data agree with GASP within the range of uncertainty (UT or measured slightly less ozone (LS. In contrast, the 1990s BM sensors show consistently and significantly higher UT/LS ozone values than MOZAIC. This unequal behaviour of aircraft/sonde comparisons in the 1970s and 1990s leads to differences in the estimated long-term changes over Europe: while the comparison between GASP and MOZAIC indicates ozone changes of −5% to 10% over Europe, the sondes suggest a much larger increase of 10%–35% depending on station and season, although statistical significance is not conclusive due to data sample limitations. In contrast to the BM sondes, the Electrochemical Cell (ECC sonde at Wallops Island, USA, measured higher UT ozone than both GASP and MOZAIC. Hence, long-term changes from GASP/MOZAIC agree within the range of uncertainty with the changes deduced from Wallops Island.
Schnadt Poberaj, C.; Staehelin, J.; Brunner, D.; Thouret, V.; de Backer, H.; Stübi, R.
2009-07-01
We present ozone measurements of the Global Atmospheric Sampling Program (GASP) performed from four commercial and one research aircraft in the late 1970s to compare them with respective measurements of the ongoing MOZAIC project. Multi-annual averages of UT/LS ozone were built using the aircraft data sets (1975-1979 and 1994-2001), and long-term changes between the 1970s and 1990s were derived by comparison. The data were binned relative to the dynamical tropopause to separate between UT and LS air masses. LS data were analysed using equivalent latitudes. In the UT, pronounced increases of 20-40% are found over the Middle East and South Asia in the spring and summer seasons. Increases are also found over Japan, Europe, and the eastern parts of the United States depending on season. LS ozone over northern mid- and high latitudes was found to be lower in the 1990s compared to the 1970s in all seasons of the year. In addition, a comparison with long-term changes deduced from ozonesondes is presented. The early 1970s European Brewer-Mast (BM) sonde data agree with GASP within the range of uncertainty (UT) or measured slightly less ozone (LS). In contrast, the 1990s BM sensors show consistently and significantly higher UT/LS ozone values than MOZAIC. This unequal behaviour of aircraft/sonde comparisons in the 1970s and 1990s leads to differences in the estimated long-term changes over Europe: while the comparison between GASP and MOZAIC indicates ozone changes of -5% to 10% over Europe, the sondes suggest a much larger increase of 10%-35% depending on station and season, although statistical significance is not conclusive due to data sample limitations. In contrast to the BM sondes, the Electrochemical Cell (ECC) sonde at Wallops Island, USA, measured higher UT ozone than both GASP and MOZAIC. Hence, long-term changes from GASP/MOZAIC agree within the range of uncertainty with the changes deduced from Wallops Island.
Nucleon charge-exchange reactions at intermediate energy
Energy Technology Data Exchange (ETDEWEB)
Alford, W.P. [Western Ontario Univ., London, ON (Canada). Dept. of Physics]|[TRIUMF, Vancouver, BC (Canada); Spicer, B.M. [Melbourne Univ., Parkville, VIC (Australia). School of Physics
1997-12-31
An historical review of the development of ideas pertaining to Gamow-Teller giant resonances is given, and a description of the emergence of techniques for the study of charge exchange reactions - particularly the technical advances which yielded the recent volume of new date. The present status of charge exchange reactions is reviewed and assessed. Evidence is presented from the {sup 14}C(p,n) reaction for the dominance of the spin-isospin component of the nucleon-nucleon interaction in intermediate energy reactions. In (p,n) reactions the Gamow-Teller giant resonance dominates the spectra, with higher multipoles contributing. By contrast, in (n,p) reactions in the heavier nuclei, the Gamow-Teller transitions are substantially Pauli-blocked and the spin dipole resonance dominates, with contributions from higher multipoles. Discussions of the multipole decomposition process, used to obtain from the data the contributions of the different multipoles, and the contributions of the multipoles, are given. 226 refs., 19 figs.
Calculating Electromagnetic Fields Of A Loop Antenna
Schieffer, Mitchell B.
1987-01-01
Approximate field values computed rapidly. MODEL computer program developed to calculate electromagnetic field values of large loop antenna at all distances to observation point. Antenna assumed to be in x-y plane with center at origin of coordinate system. Calculates field values in both rectangular and spherical components. Also solves for wave impedance. Written in MicroSoft FORTRAN 77.
46 CFR 154.520 - Piping calculations.
2010-10-01
... 46 Shipping 5 2010-10-01 2010-10-01 false Piping calculations. 154.520 Section 154.520 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... Process Piping Systems § 154.520 Piping calculations. A piping system must be designed to meet...
SGEMP Analysis using the Programmable Calculator.
1980-08-30
step represents a single key stroke on the calculator such as a multiply or storage operation.) Calculator memory can he partitioned variably between...is (in M KS units): Em = / Fmr 0 v1 E , (A-18) where F is a dimensionless number that is a function of the emission spectrum and angular distribution
10 CFR 766.102 - Calculation methodology.
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Calculation methodology. 766.102 Section 766.102 Energy DEPARTMENT OF ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF DOMESTIC UTILITIES Procedures for Special Assessment § 766.102 Calculation methodology. (a...
40 CFR 1065.850 - Calculations.
2010-07-01
... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Calculations. 1065.850 Section 1065.850 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Testing With Oxygenated Fuels § 1065.850 Calculations. Use the...
Calculated optical absorption of different perovskite phases
DEFF Research Database (Denmark)
Castelli, Ivano Eligio; Thygesen, Kristian Sommer; Jacobsen, Karsten Wedel
2015-01-01
We present calculations of the optical properties of a set of around 80 oxides, oxynitrides, and organometal halide cubic and layered perovskites (Ruddlesden-Popper and Dion-Jacobson phases) with a bandgap in the visible part of the solar spectrum. The calculations show that for different classes...
Teaching Discrete Mathematics with Graphing Calculators.
Masat, Francis E.
Graphing calculator use is often thought of in terms of pre-calculus or continuous topics in mathematics. This paper contains examples and activities that demonstrate useful, interesting, and easy ways to use a graphing calculator with discrete topics. Examples are given for each of the following topics: functions, mathematical induction and…
Using Calculators in Mathematics 12. Student Text.
Rising, Gerald R.; And Others
This student textbook is designed to incorporate programable calculators in grade 12 mathematics. The seven chapters contained in this document are: (1) Using Calculators in Mathematics; (2) Sequences, Series, and Limits; (3) Iteration, Mathematical Induction, and the Binomial Theorem; (4) Applications of the Fundamental Counting Principle; (5)…
Calculation reliability in vehicle accident reconstruction.
Wach, Wojciech
2016-06-01
The reconstruction of vehicle accidents is subject to assessment in terms of the reliability of a specific system of engineering and technical operations. In the article [26] a formalized concept of the reliability of vehicle accident reconstruction, defined using Bayesian networks, was proposed. The current article is focused on the calculation reliability since that is the most objective section of this model. It is shown that calculation reliability in accident reconstruction is not another form of calculation uncertainty. The calculation reliability is made dependent on modeling reliability, adequacy of the model and relative uncertainty of calculation. All the terms are defined. An example is presented concerning the analytical determination of the collision location of two vehicles on the road in the absence of evidential traces. It has been proved that the reliability of this kind of calculations generally does not exceed 0.65, despite the fact that the calculation uncertainty itself can reach only 0.05. In this example special attention is paid to the analysis of modeling reliability and calculation uncertainty using sensitivity coefficients and weighted relative uncertainty.
Calculated Atomic Volumes of the Actinide Metals
DEFF Research Database (Denmark)
Skriver, H.; Andersen, O. K.; Johansson, B.
1979-01-01
The equilibrium atomic volume is calculated for the actinide metals. It is possible to account for the localization of the 5f electrons taking place in americium.......The equilibrium atomic volume is calculated for the actinide metals. It is possible to account for the localization of the 5f electrons taking place in americium....
Calculation of cohesive energy of actinide metals
Institute of Scientific and Technical Information of China (English)
钱存富; 陈秀芳; 余瑞璜; 耿平; 段占强
1997-01-01
According to empirical electron theory of solids and molecules (EET), an equation for calculating the cohesive energy of actinide metals is given, the cohesive energy of 9 actinide metals with known crystal structure is calculated, which is identical with the experimental values on the whole, and the cohesive energy of 6 actinide metals with unknown crystal structure is forecast.
Atomic Structure Calculations for Neutral Oxygen
Norah Alonizan; Rabia Qindeel; Nabil Ben Nessib
2016-01-01
Energy levels and oscillator strengths for neutral oxygen have been calculated using the Cowan (CW), SUPERSTRUCTURE (SS), and AUTOSTRUCTURE (AS) atomic structure codes. The results obtained with these atomic codes have been compared with MCHF calculations and experimental values from the National Institute of Standards and Technology (NIST) database.
Calculating "g" from Acoustic Doppler Data
Torres, Sebastian; Gonzalez-Espada, Wilson J.
2006-01-01
Traditionally, the Doppler effect for sound is introduced in high school and college physics courses. Students calculate the perceived frequency for several scenarios relating a stationary or moving observer and a stationary or moving sound source. These calculations assume a constant velocity of the observer and/or source. Although seldom…
Calculation of Temperature Rise in Calorimetry.
Canagaratna, Sebastian G.; Witt, Jerry
1988-01-01
Gives a simple but fuller account of the basis for accurately calculating temperature rise in calorimetry. Points out some misconceptions regarding these calculations. Describes two basic methods, the extrapolation to zero time and the equal area method. Discusses the theoretical basis of each and their underlying assumptions. (CW)
New tool for standardized collector performance calculations
DEFF Research Database (Denmark)
Perers, Bengt; Kovacs, Peter; Olsson, Marcus;
2011-01-01
A new tool for standardized calculation of solar collector performance has been developed in cooperation between SP Technical Research Institute Sweden, DTU Denmark and SERC Dalarna University. The tool is designed to calculate the annual performance for a number of representative cities in Europe...
Efficient Calculation of Earth Penetrating Projectile Trajectories
2006-09-01
CALCULATION OF EARTH PENETRATING PROJECTILE TRAJECTORIES by Daniel F . Youch September 2006 Thesis Advisor: Joshua Gordis... Daniel F . Youch 5. FUNDING NUMBERS 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate School Monterey, CA 93943-5000 8. PERFORMING...EFFICIENT CALCULATION OF EARTH PENETRATING PROJECTILE TRAJECTORIES Daniel F . Youch Lieutenant Commander, United States Navy B.S., Temple
Sniderman, A.D.; Tremblay, A.J.; Graaf, J. de; Couture, P.
2014-01-01
OBJECTIVES: This study tests the validity of the Hattori formula to calculate LDL apoB based on plasma lipids and total apoB. METHODS: In 2178 patients in a tertiary care lipid clinic, LDL apoB calculated as suggested by Hattori et al. was compared to directly measured LDL apoB isolated by ultracent
Data base to compare calculations and observations
Energy Technology Data Exchange (ETDEWEB)
Tichler, J.L.
1985-01-01
Meteorological and climatological data bases were compared with known tritium release points and diffusion calculations to determine if calculated concentrations could replace measure concentrations at the monitoring stations. Daily tritium concentrations were monitored at 8 stations and 16 possible receptors. Automated data retrieval strategies are listed. (PSB)
Heat Calculation of Borehole Heat Exchangers
Directory of Open Access Journals (Sweden)
S. Filatov
2013-01-01
Full Text Available The paper considers a heat calculation method of borehole heat exchangers (BHE which can be used for designing and optimization of their design values and included in a comprehensive mathematical model of heat supply system with a heat pump based on utilization of low-grade heat from the ground.The developed method of calculation is based on the reduction of the problem general solution pertaining to heat transfer in BHE with due account of heat transfer between top-down and bottom-up flows of heat carrier to the solution for a boundary condition of one kind on the borehole wall. Used the a method of electrothermal analogy has been used for a calculation of the thermal resistance and the required shape factors for calculation of a borehole filler thermal resistance have been obtained numerically. The paper presents results of heat calculation of various BHE designs in accordance with the proposed method.
Zuegg, Johannes; Bliznyuk, Andrey A.; Gready, Jill E.
On the basis of arguments of complementary fit of shape and charge polarity or hydrophobicity, molecular electrostatic potentials (MEPs) around proteins are commonly used to deduce likely sites for interaction with ligands or other proteins, including for variations such as mutations. But protein MEPs calculated classically from fixed force field descriptions, including those with implicit solvent models such as in Delphi, do not allow for repolarization of protein residues within the protein system; hence, their representations are likely to be variably inaccurate. Linear-scaling methods now allow calculation of MEPs quantum mechanically for systems as large as proteins, and can account for polarization explicitly. Here we compare MEPs derived from AM1 charge distributions calculated by Mopac2000 with those from the classical Amber force field. Our models are mutants of prion protein (PrP), a protein with an unusually high number of charged residues. The results demonstrate that static point charges, as used in most current force fields, cannot reproduce the MEP of macromolecules. Also, it is not sufficient to account for the influence of nearby atoms connected by chemical bonds; the influence of nearby atoms in space is at least as important. Thus, further progress in the accuracy and wider applicability of force fields requires proper accounting for polarization. Mopac2000 calculations can provide the necessary data for checking new force fields and/or parameter fitting.
Klasen, M
2009-01-01
We perform next-to-leading order calculations of the single-diffractive and non-diffractive cross sections for dijet production in proton-antiproton collisions at the Tevatron. By comparing their ratio to the data published by the CDF collaboration for two different center-of-mass energies, we deduce the rapidity-gap survival probability as a function of the momentum fraction of the parton in the antiproton. Assuming Regge factorization, this probability can be interpreted as a suppression factor for the diffractive structure function measured in deep-inelastic scattering at HERA. In contrast to the observations for photoproduction, the suppression factor in proton-antiproton collisions depends on the momentum fraction of the parton in the Pomeron even at next-to-leading order.
Klasen, Michael; Kramer, Gustav
2009-10-01
We perform next-to-leading order calculations of the single-diffractive and nondiffractive cross sections for dijet production in proton-antiproton collisions at the Tevatron. By comparing their ratio to the data published by the CDF collaboration for two different center-of-mass energies, we deduce the rapidity-gap survival probability as a function of the momentum fraction of the parton in the antiproton. Assuming Regge factorization, this probability can be interpreted as a suppression factor for the diffractive structure function measured in deep-inelastic scattering at HERA. In contrast to the observations for photoproduction, the suppression factor in proton-antiproton collisions depends on the momentum fraction of the parton in the Pomeron even at next-to-leading order.
Energy Technology Data Exchange (ETDEWEB)
Klasen, M. [Univ. Joseph Fourier, Laboratoire de Physique Subatomique et de Cosmologie, Grenoble (France); Kramer, G. [Univ. Hamburg, II. Inst. fuer Theoretische Physik (Germany)
2009-08-15
We perform next-to-leading order calculations of the single-diffractive and non-diffractive cross sections for dijet production in proton-antiproton collisions at the Tevatron. By comparing their ratio to the data published by the CDF collaboration for two different center-of-mass energies, we deduce the rapidity-gap survival probability as a function of the momentum fraction of the parton in the antiproton. Assuming Regge factorization, this probability can be interpreted as a suppression factor for the diffractive structure function measured in deep-inelastic scattering at HERA. In contrast to the observations for photoproduction, the suppression factor in protonantiproton collisions depends on the momentum fraction of the parton in the Pomeron even at next-to-leading order. (orig.)
Influence of polarization and a source model for dose calculation in MRT
Energy Technology Data Exchange (ETDEWEB)
Bartzsch, Stefan, E-mail: s.bartzsch@dkfz.de; Oelfke, Uwe [The Institute of Cancer Research, 15 Cotswold Road, Belmont, Sutton, Surrey SM2 5NG, United Kingdom and Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, D-69120 Heidelberg (Germany); Lerch, Michael; Petasecca, Marco [Centre for Medical Radiation Physics, University of Wollongong, Northfields Avenue, Wollongong 2522 (Australia); Bräuer-Krisch, Elke [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38000 Grenoble (France)
2014-04-15
Purpose: Microbeam Radiation Therapy (MRT), an alternative preclinical treatment strategy using spatially modulated synchrotron radiation on a micrometer scale, has the great potential to cure malignant tumors (e.g., brain tumors) while having low side effects on normal tissue. Dose measurement and calculation in MRT is challenging because of the spatial accuracy required and the arising high dose differences. Dose calculation with Monte Carlo simulations is time consuming and their accuracy is still a matter of debate. In particular, the influence of photon polarization has been discussed in the literature. Moreover, it is controversial whether a complete knowledge of phase space trajectories, i.e., the simulation of the machine from the wiggler to the collimator, is necessary in order to accurately calculate the dose. Methods: With Monte Carlo simulations in the Geant4 toolkit, the authors investigate the influence of polarization on the dose distribution and the therapeutically important peak to valley dose ratios (PVDRs). Furthermore, the authors analyze in detail phase space information provided byMartínez-Rovira et al. [“Development and commissioning of a Monte Carlo photon model for the forthcoming clinical trials in microbeam radiation therapy,” Med. Phys. 39(1), 119–131 (2012)] and examine its influence on peak and valley doses. A simple source model is developed using parallel beams and its applicability is shown in a semiadjoint Monte Carlo simulation. Results are compared to measurements and previously published data. Results: Polarization has a significant influence on the scattered dose outside the microbeam field. In the radiation field, however, dose and PVDRs deduced from calculations without polarization and with polarization differ by less than 3%. The authors show that the key consequences from the phase space information for dose calculations are inhomogeneous primary photon flux, partial absorption due to inclined beam incidence outside
Romo-Figueroa, María Gabriela; Vargas-Requena, Claudia; Sotelo-Mundo, Rogerio R; Vargas-Albores, Francisco; Higuera-Ciapara, Inocencio; Söderhäll, Kenneth; Yepiz-Plascencia, Gloria
2004-06-01
The hemolymph pattern-recognition beta-glucan binding protein from the white shrimp Penaeus (Litopenaeus) vannamei is also a high density lipoprotein (betaGBP-HDL) involved in innate immunity. The betaGBP-HDL full length cDNA sequence determined was 6.3 kb long, and contains a long 3'UTR region with a polyadenylation signal and a poly-A+ tail. The open reading frame is 1454 amino acids long and the N-terminal residue of the mature protein is localized in position 198 of the ORF. Comparison of the betaGBP-HDL amino acid sequence against GenBank detected only significant similarity to betaGBP from the crayfish Pacifastacus leniusculus. betaGBP-HDL is expressed in hepatopancreas, muscle, pleopods and gills, but not in hemocytes as determined by RT-PCR. We discuss the analysis of the deduced primary sequence in terms of the predicted secondary structure, glucanase-like and RGD motives relevant to its dual roles in defence and lipid transport.
Development of Fast running DNBR Calculation Code
Energy Technology Data Exchange (ETDEWEB)
Kwon, Hyuk; Seo, K. W.; Kim, S. J.; Hwang, D. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2010-10-15
SMART core adopted a core protection(SCOPS) and a supervising system(SCOMS) to satisfy the SAFDL for AOO and normal operation. Generally, the criteria is limited to the DNBR limit so that the DNBR calculation module is required in the protection and the supervising system of core. There are CPU time limit and calculation robustness as some requirements of the DNBR calculation module in SCOPS and SCOMS caused by hardware limitations. The non-iterative few channel methods are needed to satisfy the requirements. Non-iterative numerical method is similar to the CETOP algorithm originated from ref. 1. The method is known as the non-iterative prediction and correction method. An optimum number of channels for core lumping model is selected as 4- channel which is same channel number of CETOP model. A compensation model of lumped channel is needed to ensure that the 4-channel thermal hydraulic field is nearly equivalent to that field of 1/8-core model that is calculated by MATRA-S. The code called FAST that is fast running DNBR calculation is developed to satisfy the requirements of CPU time and calculation robustness. Present paper is described of characteristics and calculation results of developed FAST code
Validation of fluorescence transition probability calculations
Pia, M G; Sudhaka, Manju
2009-01-01
A systematic and quantitative validation of the K and L shell X-ray transition probability calculations according to different theoretical methods has been performed against experimental data. This study is relevant to the optimization of data libraries used by software systems, namely Monte Carlo codes, dealing with X-ray fluorescence. The results support the adoption of transition probabilities calculated according to the Hartree-Fock approach, which manifest better agreement with experimental measurements than calculations based on the Hartree-Slater method.
Program Calculates Current Densities Of Electronic Designs
Cox, Brian
1996-01-01
PDENSITY computer program calculates current densities for use in calculating power densities of electronic designs. Reads parts-list file for given design, file containing current required for each part, and file containing size of each part. For each part in design, program calculates current density in units of milliamperes per square inch. Written by use of AWK utility for Sun4-series computers running SunOS 4.x and IBM PC-series and compatible computers running MS-DOS. Sun version of program (NPO-19588). PC version of program (NPO-19171).
Spreadsheet Based Scaling Calculations and Membrane Performance
Energy Technology Data Exchange (ETDEWEB)
Wolfe, T D; Bourcier, W L; Speth, T F
2000-12-28
Many membrane element manufacturers provide a computer program to aid buyers in the use of their elements. However, to date there are few examples of fully integrated public domain software available for calculating reverse osmosis and nanofiltration system performance. The Total Flux and Scaling Program (TFSP), written for Excel 97 and above, provides designers and operators new tools to predict membrane system performance, including scaling and fouling parameters, for a wide variety of membrane system configurations and feedwaters. The TFSP development was funded under EPA contract 9C-R193-NTSX. It is freely downloadable at www.reverseosmosis.com/download/TFSP.zip. TFSP includes detailed calculations of reverse osmosis and nanofiltration system performance. Of special significance, the program provides scaling calculations for mineral species not normally addressed in commercial programs, including aluminum, iron, and phosphate species. In addition, ASTM calculations for common species such as calcium sulfate (CaSO{sub 4}{times}2H{sub 2}O), BaSO{sub 4}, SrSO{sub 4}, SiO{sub 2}, and LSI are also provided. Scaling calculations in commercial membrane design programs are normally limited to the common minerals and typically follow basic ASTM methods, which are for the most part graphical approaches adapted to curves. In TFSP, the scaling calculations for the less common minerals use subsets of the USGS PHREEQE and WATEQ4F databases and use the same general calculational approach as PHREEQE and WATEQ4F. The activities of ion complexes are calculated iteratively. Complexes that are unlikely to form in significant concentration were eliminated to simplify the calculations. The calculation provides the distribution of ions and ion complexes that is used to calculate an effective ion product ''Q.'' The effective ion product is then compared to temperature adjusted solubility products (Ksp's) of solids in order to calculate a Saturation Index (SI
Pressure vessel calculations for VVER-440 reactors.
Hordósy, G; Hegyi, Gy; Keresztúri, A; Maráczy, Cs; Temesvári, E; Vértes, P; Zsolnay, E
2005-01-01
For the determination of the fast neutron load of the reactor pressure vessel a mixed calculational procedure was developed. The procedure was applied to the Unit II of Paks NPP, Hungary. The neutron source on the outer surfaces of the reactor was determined by a core design code, and the neutron transport calculations outside the core were performed by the Monte Carlo code MCNP. The reaction rate in the activation detectors at surveillance positions and at the cavity were calculated and compared with measurements. In most cases, fairly good agreement was found.
Hamming generalized corrector for reactivity calculation
Energy Technology Data Exchange (ETDEWEB)
Suescun-Diaz, Daniel; Ibarguen-Gonzalez, Maria C.; Figueroa-Jimenez, Jorge H. [Pontificia Universidad Javeriana Cali, Cali (Colombia). Dept. de Ciencias Naturales y Matematicas
2014-06-15
This work presents the Hamming method generalized corrector for numerically resolving the differential equation of delayed neutron precursor concentration from the point kinetics equations for reactivity calculation, without using the nuclear power history or the Laplace transform. A study was carried out of several correctors with their respective modifiers with different time step calculations, to offer stability and greater precision. Better results are obtained for some correctors than with other existing methods. Reactivity can be calculated with precision of the order h{sup 5}, where h is the time step. (orig.)
Assessment of seismic margin calculation methods
Energy Technology Data Exchange (ETDEWEB)
Kennedy, R.P.; Murray, R.C.; Ravindra, M.K.; Reed, J.W.; Stevenson, J.D.
1989-03-01
Seismic margin review of nuclear power plants requires that the High Confidence of Low Probability of Failure (HCLPF) capacity be calculated for certain components. The candidate methods for calculating the HCLPF capacity as recommended by the Expert Panel on Quantification of Seismic Margins are the Conservative Deterministic Failure Margin (CDFM) method and the Fragility Analysis (FA) method. The present study evaluated these two methods using some representative components in order to provide further guidance in conducting seismic margin reviews. It is concluded that either of the two methods could be used for calculating HCLPF capacities. 21 refs., 9 figs., 6 tabs.
Neutron skyshine calculations for the PDX tokamak
Energy Technology Data Exchange (ETDEWEB)
Wheeler, F.J.; Nigg, D.W.
1979-01-01
The Poloidal Divertor Experiment (PDX) at Princeton will be the first operating tokamak to require a substantial radiation shield. The PDX shielding includes a water-filled roof shield over the machine to reduce air scattering skyshine dose in the PDX control room and at the site boundary. During the design of this roof shield a unique method was developed to compute the neutron source emerging from the top of the roof shield for use in Monte Carlo skyshine calculations. The method is based on simple, one-dimensional calculations rather than multidimensional calculations, resulting in considerable savings in computer time and input preparation effort. This method is described.
Energy of plate tectonics calculation and projection
Directory of Open Access Journals (Sweden)
N. H. Swedan
2013-02-01
Full Text Available Mathematics and observations suggest that the energy of the geological activities resulting from plate tectonics is equal to the latent heat of melting, calculated at mantle's pressure, of the new ocean crust created at midocean ridges following sea floor spreading. This energy varies with the temperature of ocean floor, which is correlated with surface temperature. The objective of this manuscript is to calculate the force that drives plate tectonics, estimate the energy released, verify the calculations based on experiments and observations, and project the increase of geological activities with surface temperature rise caused by climate change.
Ti-84 Plus graphing calculator for dummies
McCalla
2013-01-01
Get up-to-speed on the functionality of your TI-84 Plus calculator Completely revised to cover the latest updates to the TI-84 Plus calculators, this bestselling guide will help you become the most savvy TI-84 Plus user in the classroom! Exploring the standard device, the updated device with USB plug and upgraded memory (the TI-84 Plus Silver Edition), and the upcoming color screen device, this book provides you with clear, understandable coverage of the TI-84's updated operating system. Details the new apps that are available for download to the calculator via the USB cabl
The WFIRST Galaxy Survey Exposure Time Calculator
Hirata, Christopher M.; Gehrels, Neil; Kneib, Jean-Paul; Kruk, Jeffrey; Rhodes, Jason; Wang, Yun; Zoubian, Julien
2013-01-01
This document describes the exposure time calculator for the Wide-Field Infrared Survey Telescope (WFIRST) high-latitude survey. The calculator works in both imaging and spectroscopic modes. In addition to the standard ETC functions (e.g. background and SN determination), the calculator integrates over the galaxy population and forecasts the density and redshift distribution of galaxy shapes usable for weak lensing (in imaging mode) and the detected emission lines (in spectroscopic mode). The source code is made available for public use.
Multigrid Methods in Electronic Structure Calculations
Briggs, E L; Bernholc, J
1996-01-01
We describe a set of techniques for performing large scale ab initio calculations using multigrid accelerations and a real-space grid as a basis. The multigrid methods provide effective convergence acceleration and preconditioning on all length scales, thereby permitting efficient calculations for ill-conditioned systems with long length scales or high energy cut-offs. We discuss specific implementations of multigrid and real-space algorithms for electronic structure calculations, including an efficient multigrid-accelerated solver for Kohn-Sham equations, compact yet accurate discretization schemes for the Kohn-Sham and Poisson equations, optimized pseudo\\-potentials for real-space calculations, efficacious computation of ionic forces, and a complex-wavefunction implementation for arbitrary sampling of the Brillioun zone. A particular strength of a real-space multigrid approach is its ready adaptability to massively parallel computer architectures, and we present an implementation for the Cray-T3D with essen...