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Sample records for antineutrino charge-exchange reactions

  1. Neutrino and antineutrino charge-exchange reactions on 12C

    International Nuclear Information System (INIS)

    We extend the formalism of weak interaction processes, obtaining new expressions for the transition rates, which greatly facilitate numerical calculations, for both neutrino-nucleus reactions and muon capture. Explicit violation of the conserved vector current hypothesis by the Coulomb field, as well as development of a sum-rule approach for inclusive cross sections, has been worked out. We have done a thorough study of exclusive (ground-state) properties of 12B and 12N within the projected quasiparticle random phase approximation (PQRPA). Good agreement with experimental data achieved in this way put into evidence the limitations of the standard RPA and QRPA models, which come from the inability of the RPA to open the p3/2 shell and from the nonconservation of the number of particles in the QRPA. The inclusive neutrino/antineutrino (ν/ν-tilde) reactions 12C(ν,e-)12N and 12C(ν-tilde,e+)12B are calculated within both the PQRPA and the relativistic QRPA. It is found that (i) the magnitudes of the resulting cross sections are close to the sum-rule limit at low energy, but significantly smaller than this limit at high energies, for both ν and ν-tilde; (ii) they increase steadily when the size of the configuration space is augmented, particularly for ν/ν-tilde energies >200 MeV; and (iii) they converge for sufficiently large configuration space and final-state spin. The quasi-elastic 12C(ν,μ-)12N cross section recently measured in the MiniBooNE experiment is briefly discussed. We study the decomposition of the inclusive cross section based on the degree of forbiddenness of different multipoles. A few words are dedicated to the ν/ν-tilde-12C charge-exchange reactions related to astrophysical applications.

  2. Multistep processes in charge-exchange reactions

    CERN Document Server

    Demetriou, P; Marianski, B

    2002-01-01

    Cross sections for the charge-exchange sup 6 sup 5 Cu(p, n) sup 6 sup 5 Zn reaction at the incident energy of 27 MeV and the sup 1 sup 0 sup 0 Mo(p, n) sup 1 sup 0 sup 0 Tc reaction at the incident energy of 26 MeV have been calculated using the multistep direct reaction theory of Feshbach, Kerman and Koonin. The theory was modified to include the non-DWBA matrix elements and the isovector collective vibrations according to the prescription of Marcinkowski and Marianski. The results show enhanced contributions from two-, three- and four-step direct reactions in agreement with experiment.

  3. Study of nuclei' excitation in the charge exchange reactions (Draft)

    International Nuclear Information System (INIS)

    Carried out experimental and theoretical studies show, that in the nuclear charge exchange reactions there is an unique ability for study both properties and behavior of the delta-isobar in the excited nuclear environment. However for theoretical analysis of these reactions it is necessary have experimental data on nuclei charge exchange on free nucleons. It is offered the experiment of measurement dependence of inclusive cross section of the tritium nuclei charge exchange in 3He nuclei on hydrogen from transferred energy. This reaction is isotopically dependent on 3He nuclei in tritons charge exchange reaction on neutrons. Aim of proposed experiment is checking of a hypothesis believability about the delta-isobar excitation in flying nucleus, and measurement of the process intensity. Peculiarity of this experiment is application of relativistic tritons beams formed from accelerated fragments of 4He nuclei. Experimental facility presents of combination of two one-arm spectrometers: first one - time-flying spectrometer for measurement tritium nuclei impulse in beam to target with accuracy 0.3 % for 6 GeV/s and identification of tritium nuclei, the second one - magnetic spectrometer for identification and measurement of 3He nuclei impulse forming in the result of the charge exchange reaction

  4. Charge exchange and chemical reactions with trapped Th3+

    International Nuclear Information System (INIS)

    We have measured the reaction rates of trapped, buffer gas cooled Th3+ and various gases and have analyzed the reaction products using trapped ion mass spectrometry techniques. Ion trap lifetimes are usually limited by reactions with background molecules, and the high electron affinity of multiply charged ions such as Th3+ make them more prone to loss. Our results show that reactions of Th3+ with carbon dioxide, methane, and oxygen all occur near the classical Langevin rate, while reaction rates with argon, hydrogen, and nitrogen are orders of magnitude lower. Reactions of Th3+ with oxygen and methane proceed primarily via charge exchange, while simultaneous charge exchange and chemical reaction occurs between Th3+ and carbon dioxide. Loss rates of Th3+ in helium are consistent with reaction with impurities in the gas. Reaction rates of Th3+ with nitrogen and argon depend on the internal electronic configuration of the Th3+.

  5. Charge Exchange and Chemical Reactions with Trapped Th$^{3+}$

    CERN Document Server

    Churchill, L R; Chapman, M S

    2010-01-01

    We have measured the reaction rates of trapped, buffer gas cooled Th$^{3+}$ and various gases and have analyzed the reaction products using trapped ion mass spectrometry techniques. Ion trap lifetimes are usually limited by reactions with background molecules, and the high electron affinity of multiply charged ions such as Th$^{3+}$ make them more prone to loss. Our results show that reactions of Th$^{3+}$ with carbon dioxide, methane, and oxygen all occur near the classical Langevin rate, while reaction rates with argon, hydrogen, and nitrogen are orders of magnitude lower. Reactions of Th$^{3+}$ with oxygen and methane proceed primarily via charge exchange, while simultaneous charge exchange and chemical reaction occurs between Th$^{3+}$ and carbon dioxide. Loss rates of Th$^{3+}$ in helium are consistent with reaction with impurities in the gas. Reaction rates of Th$^{3+}$ with nitrogen and argon depend on the internal electronic configuration of the Th$^{3+}$.

  6. Pion charge-exchange reactions: The analog state transitions

    International Nuclear Information System (INIS)

    The general features of pion charge-exchange reactions leading to nuclear-isobaric-analog states (IAS) and double-isobaric-analog states (DIAS), as they have emerged from studies over the past ten years, are reviewed. The energy range investigated is 20 to 550 MeV for IAS transitions and 20 to 300 MeV for DIAS transitions. These data are seen to play an important role in characterizing the pion optical potential, in determining the Δ-N interaction in nuclei, and in the study of nucleon correlations in nuclei. Recent progress achieved in understanding the role of such correlations in double-charge-exchange reactions is reviewed. 55 refs., 43 figs., 3 tabs

  7. Deuteron-proton charge exchange reaction at small transfer momentum

    CERN Document Server

    Ladygina, N B

    2004-01-01

    The charge-exchange reaction pd -> npp at 1 GeV projectile proton energy is studied. This reaction is considered in a special kinematics, when the transfer momentum from the beam proton to fast outgoing neutron is close to zero. Our approach is based on the Alt-Grassberger-Sandhas formulation of the multiple-scattering theory for the three-nucleon system. The matrix inversion method has been applied to take account of the final state interaction (FSI) contributions. The differential cross section, tensor analyzing power $C_{0,yy}$, vector-vector $C_{y,y}$ and vector-tensor $C_{y,xz}$ spin correlation parameters of the initial particles are presented. It is shown, that the FSI effects play a very important role under such kinematical conditions. The high sensitivity of the considered observables to the elementary nucleon-nucleon amplitudes has been obtained.

  8. Delta excitation in nuclei: the lesson of charge exchange reactions

    International Nuclear Information System (INIS)

    We present an attempt of theoretical interpretation of charge exchange reactions on nuclei in the region of the delta resonance. Special care is taken to insure consistency with the constraints from pion and photon excitation channels. Good agreement with measured spectra can be obtained for all types of targets and incident ions except for polarized deuterons data which appear hardly reconcilable with the others within our interpretation. Despite the peripheral character of these reactions, a sizeable part of the observed downward shift of the resonance is possibly ascribable to a yet undetected collective mode of the nucleus at high excitation, the pionic branch. Our limited commitment is due to uncomplete knowledge of the NN → N Δ interaction and the transition form factors of the probing ions which has been palliated by some phenomenology

  9. Charge Exchange Reaction in Dopant-Assisted Atmospheric Pressure Chemical Ionization and Atmospheric Pressure Photoionization.

    Science.gov (United States)

    Vaikkinen, Anu; Kauppila, Tiina J; Kostiainen, Risto

    2016-08-01

    The efficiencies of charge exchange reaction in dopant-assisted atmospheric pressure chemical ionization (DA-APCI) and dopant-assisted atmospheric pressure photoionization (DA-APPI) mass spectrometry (MS) were compared by flow injection analysis. Fourteen individual compounds and a commercial mixture of 16 polycyclic aromatic hydrocarbons were chosen as model analytes to cover a wide range of polarities, gas-phase ionization energies, and proton affinities. Chlorobenzene was used as the dopant, and methanol/water (80/20) as the solvent. In both techniques, analytes formed the same ions (radical cations, protonated molecules, and/or fragments). However, in DA-APCI, the relative efficiency of charge exchange versus proton transfer was lower than in DA-APPI. This is suggested to be because in DA-APCI both dopant and solvent clusters can be ionized, and the formed reagent ions can react with the analytes via competing charge exchange and proton transfer reactions. In DA-APPI, on the other hand, the main reagents are dopant-derived radical cations, which favor ionization of analytes via charge exchange. The efficiency of charge exchange in both DA-APPI and DA-APCI was shown to depend heavily on the solvent flow rate, with best efficiency seen at lowest flow rates studied (0.05 and 0.1 mL/min). Both DA-APCI and DA-APPI showed the radical cation of chlorobenzene at 0.05-0.1 mL/min flow rate, but at increasing flow rate, the abundance of chlorobenzene M(+.) decreased and reagent ion populations deriving from different gas-phase chemistry were recorded. The formation of these reagent ions explains the decreasing ionization efficiency and the differences in charge exchange between the techniques. Graphical Abstract ᅟ.

  10. Electron capture rates in stars studied with heavy ion charge exchange reactions

    CERN Document Server

    Bertulani, C A

    2015-01-01

    Indirect methods using nucleus-nucleus reactions at high energies (here, high energies mean $\\sim$ 50 MeV/nucleon and higher) are now routinely used to extract information of interest for nuclear astrophysics. This is of extreme relevance as many of the nuclei involved in stellar evolution are short-lived. Therefore, indirect methods became the focus of recent studies carried out in major nuclear physics facilities. Among such methods, heavy ion charge exchange is thought to be a useful tool to infer Gamow-Teller matrix elements needed to describe electron capture rates in stars and also double beta-decay experiments. In this short review, I provide a theoretical guidance based on a simple reaction model for charge exchange reactions.

  11. Charge-exchange reaction by Reggeon exchange and W{sup +}W{sup −}-fusion

    Energy Technology Data Exchange (ETDEWEB)

    Schicker, R. [Phys. Inst., University Heidelberg (Germany)

    2015-04-10

    Charge-exchange reactions at high energies are examined. The existing cross section data on the Reggeon induced reaction pp → n + Δ{sup ++} taken at the ZGS and ISR accelerators are extrapolated to the energies of the RHIC and LHC colliders. The interest in the charge-exchange reaction induced by W{sup ±}-fusion is presented, and the corresponding QCD-background is examined.

  12. Search for Tetraneutron by Pion Double Charge Exchange Reaction at J-PARC

    CERN Document Server

    Fujioka, Hiroyuki; Harada, Toru; Hiyama, Emiko; Itahashi, Kenta; Kanatsuki, Shunsuke; Nagae, Tomofumi; Nanamura, Takuya; Nishi, Takahiro

    2016-01-01

    Tetraneutron ($^4n$) has come back in the limelight, because of recent observation of a candidate resonant state at RIBF. We propose to investigate the pion double charge exchange (DCX) reaction, i.e. $^4\\mathrm{He}({\\pi}^- , {\\pi}^+)$, as an alternative way to populate tetraneutron. An intense ${\\pi}^-$ beam with the kinetic energy of ~850 MeV, much higher than that in past experiments at LAMPF and TRIUMF, will open up a possibility to improve the experimental sensitivity of the formation cross section, which will be much smaller than hitherto known DCX cross sections such as $^9\\mathrm{Be}({\\pi}^-, {\\pi}^+)^9\\mathrm{He}\\ (g.s.)$.

  13. Spin dipole nuclear matrix elements for double beta decay nuclei by charge-exchange reactions

    CERN Document Server

    Ejiri, H

    2016-01-01

    Spin dipole (SD) strengths for double beta-decay (DBD) nuclei were studied experimentally for the first time by using measured cross sections of (3He,t) charge exchange reactions (CERs). Then SD nuclear matrix elements (NMEs) for low-lying 2- states were derived from the experimental SD strengths by referring to the experimental GT (Gamow-Teller) and F (Fermi) strengths. They are consistent with the empirical SD NMEs based on the quasi-particle model with the empirical effective SD coupling constant. The CERs are used to evaluate the SD NME, which is associated with one of the major components of the neutrino-less DBD NME.

  14. Neutrino nuclear responses for double beta decays and astro neutrinos by charge exchange reactions

    Science.gov (United States)

    Ejiri, Hiroyasu

    2014-09-01

    Neutrino nuclear responses are crucial for neutrino studies in nuclei. Charge exchange reactions (CER) are shown to be used to study charged current neutrino nuclear responses associated with double beta decays(DBD)and astro neutrino interactions. CERs to be used are high energy-resolution (He3 ,t) reactions at RCNP, photonuclear reactions via IAR at NewSUBARU and muon capture reactions at MUSIC RCNP and MLF J-PARC. The Gamow Teller (GT) strengths studied by CERs reproduce the observed 2 neutrino DBD matrix elements. The GT and spin dipole (SD) matrix elements are found to be reduced much due to the nucleon spin isospin correlations and the non-nucleonic (delta isobar) nuclear medium effects. Impacts of the reductions on the DBD matrix elements and astro neutrino interactions are discussed.

  15. Search for AN Eta-Nuclear Bound State in the Double Charge Exchange Reaction OXYGEN-18

    Science.gov (United States)

    Johnson, John Doeppers

    1992-01-01

    Recent calculations have predicted that a bound state between an eta and a nucleus may occur as an intermediate state in pion double charge exchange (DCX). The existence of such a mesic nucleus would lead to a resonance-like structure in the DCX excitation function at fixed momentum transfer. LAMPF Experiment 1140 searched for an eta-nucleus bound state in the DCX reaction ^{18}O(pi ^{+}, pi^ {-})^{18}Ne(DIAS). An excitation function for this reaction was measured for energies ranging from 350 to 440 MeV and for momentum transfers of q = 0, 105 and 210 MeV/c. The calculated cross sections agree favorably with previously published data. Theoretical calculations predict that a resonance structure will be evidenced by an enhanced cross section at the eta production threshold for this reaction. The measured excitation function has found some evidence of structure in this region.

  16. 36-MeV-triton-induced charge exchange: Mass measurements and energy levels of neutron-rich nuclei and the charge exchange reaction mechanism

    International Nuclear Information System (INIS)

    Energy spectra and differential cross sections have been obtained for the charge exchange reaction (3H,3He) on targets of /sup 30,28/Si and /sup 26/Mg at an incident energy of 36 MeV. Previously unobserved energy levels of /sup 30/Al and /sup 26/Na are reported and compared to shell model predictions. Microscopic form factors based on the M3Y effective nucleon-nucleon interaction are used in distorted-wave Born approximation codes to fit the data. The sensitivity of the model to input parameters is discussed and some spin assignments made. Coupled channels calculations are performed to fit the two-step contributions to the data via sequential one-nucleon transfers

  17. Pion nucleus single charge exchange reactions above the Δ(1232) resonance

    International Nuclear Information System (INIS)

    Forward-angle differential cross sections for the (π+, π0) reaction leading to the Isobaric Analog State in the residual nuclei at 300, 425, 500 and 550 MeV have been measured. Targets ranged in mass from 7Li to 208Pb. A description of the experimental setup and the analysis is presented. The 00 cross sections are found to rise markedly between 300 and 425 MeV, contrary to the extrapolation from the lower energy data and to the behavior of the free pion-nucleon single charge exchange process. The angular distributions are sharply forward peaked. Systematics of the data indicate increased volume penetration with increasing pion beam energy. The cross sections are compared with the results of Glauber model calculations indicating the significance of higher order processes even at these energies. 67 refs., 40 figs., 22 tabs

  18. Pion induced double charge exchange reactions in the Delta resonance region

    CERN Document Server

    Buss, O; Larionov, A B; Mosel, U

    2006-01-01

    We have applied the Giessen BUU (GiBUU) transport model to the description of the double charge exchange (DCX) reaction of pions with different nuclear targets at incident kinetic energies of 120-180 MeV . The DCX process is highly sensitive to details of the interactions of pions with the nuclear medium and, therefore, represents a major benchmark for any model of pion scattering off nuclei at low and intermediate energies. The impact of surface effects, such as the neutron skins of heavy nuclei, is investigated. The dependence of the total cross section on the nuclear mass number is also discussed. We achieve a good quantitative agreement with the extensive data set obtained at LAMPF. Furthermore, we compare the solutions of the transport equations obtained in the test-particle ansatz using two different schemes - the full and the parallel ensemble method.

  19. The neutron-proton charge-exchange amplitudes measured in the dp -> ppn reaction

    CERN Document Server

    Mchedlishvili, D; Carbonell, J; Chiladze, D; Dymov, S; Dzyuba, A; Engels, R; Gebel, R; Glagolev, V; Grigoryev, K; Goslawski, P; Hartmann, M; Kacharava, A; Kamerdzhiev, V; Keshelashvili, I; Khoukaz, A; Komarov, V; Kulessa, P; Kulikov, A; Lehrach, A; Lomidze, N; Lorentz, B; Macharashvili, G; Maier, R; Merzliakov, S; Mielke, M; Mikirtychyants, M; Mikirtychyants, S; Nioradze, M; Ohm, H; Papenbrock, M; Prasuhn, D; Rathmann, F; Serdyuk, V; Seyfarth, H; Stein, H J; Steffens, E; Stockhorst, H; Stroeher, H; Tabidze, M; Trusov, S; Uzikov, Yu; Valdau, Yu; Wilkin, C

    2012-01-01

    The unpolarised differential cross section and the two deuteron tensor analysing powers A_{xx} and A_{yy} of the pol{d}p -> (pp)n charge-exchange reaction have been measured with the ANKE spectrometer at the COSY storage ring. Using deuteron beams with energies 1.2, 1.6, 1.8, and 2.27 GeV, data were obtained for small momentum transfers to a (pp) system with low excitation energy. The results at the three lower energies are consistent with impulse approximation predictions based upon the current knowledge of the neutron-proton amplitudes. However, at 2.27GeV, where these amplitudes are far more uncertain, agreement requires a reduction in the overall double-spin-flip contribution, with an especially significant effect in the longitudinal direction. These conclusions are supported by measurements of the deuteron-proton spin-correlation parameters C_{x,x} and C_{y,y} that were carried out in the pol{d}pol{p} -> (pp)n reaction at 1.2 and 2.27GeV. The values obtained for the proton analysing power also suggest th...

  20. Charge-exchange reactions from the standpoint of the parton model

    Energy Technology Data Exchange (ETDEWEB)

    Nekrasov, M.L. [SRC Institute for High Energy Physics of NRC ' ' Kurchatov Institute' ' , Protvino (Russian Federation)

    2015-11-15

    Using simple arguments, we show that charge-exchange reactions at high energies go through the hard scattering of fast quarks. On this basis we describe π{sup -}p → M{sup 0}n and K{sup -}p → M{sup 0}Λ, M{sup 0} = π{sup 0},η,η', in a combined approach which defines hard contributions in the parton model and soft ones in Regge phenomenology. The disappearance of a dip according to recent GAMS-4π data in the differential cross-section K{sup -}p → ηΛ at vertical stroke t vertical stroke ∼ 0.4-0.5 (GeV/c){sup 2} at transition to relatively high momenta, is explained as a manifestation of a mode change of summation of hard contributions from coherent to incoherent. Other manifestations of the mentioned mode change are discussed. Constraints on the η - η' mixing and gluonium admixture in η' are obtained. (orig.)

  1. Heavy-ion double charge exchange reactions: A tool toward 0 νββ nuclear matrix elements

    Energy Technology Data Exchange (ETDEWEB)

    Cappuzzello, F.; Bondi, M. [Universita di Catania, Dipartimento di Fisica e Astronomia, Catania (Italy); INFN, Laboratori Nazionali del Sud, Catania (Italy); Cavallaro, M.; Agodi, C.; Carbone, D.; Cunsolo, A. [INFN, Laboratori Nazionali del Sud, Catania (Italy); Foti, A. [Universita di Catania, Dipartimento di Fisica e Astronomia, Catania (Italy); INFN, Sezione di Catania, Catania (Italy)

    2015-11-15

    The knowledge of the nuclear matrix elements for the neutrinoless double beta decay is fundamental for neutrino physics. In this paper, an innovative technique to extract information on the nuclear matrix elements by measuring the cross section of a double charge exchange nuclear reaction is proposed. The basic point is that the initial- and final-state wave functions in the two processes are the same and the transition operators are similar. The double charge exchange cross sections can be factorized in a nuclear structure term containing the matrix elements and a nuclear reaction factor. First pioneering experimental results for the {sup 40}Ca({sup 18}O,{sup 18}Ne){sup 40}Ar reaction at 270 MeV incident energy show that such cross section factorization reasonably holds for the crucial 0{sup +} → 0{sup +} transition to {sup 40}Ar{sub gs}, at least at very forward angles. (orig.)

  2. Heavy-ion double charge exchange reactions: a tool towards 0v\\b{eta}\\b{eta} nuclear matrix elements

    CERN Document Server

    Cappuzzello, F; Agodi, C; Bond`ı, M; Carbone, D; Cunsolo, A; Foti, A

    2015-01-01

    The knowledge of the nuclear matrix elements for the neutrinoless double beta decay is fundamental for neutrino physics. In this paper, an innovative technique to extract information on the nuclear matrix elements by measuring the cross section of a double charge exchange nuclear reaction is proposed. The basic point is that the initial and final state wave functions in the two processes are the same and the transition operators are similar. The double charge exchange cross sections can be factorized in a nuclear structure term containing the matrix elements and a nuclear reaction factor. First pioneering experimental results for the 40Ca(18O,18Ne)40Ar reaction at 270 MeV incident energy show that such cross section factorization reasonably holds for the crucial 0+ --> 0+ transition to 40Args, at least at very forward angles.

  3. Study of the pd→→n{pp}s charge-exchange reaction using a polarised deuterium target

    Directory of Open Access Journals (Sweden)

    B. Gou

    2015-02-01

    Full Text Available The vector and tensor analysing powers, Ay and Ayy, of the pd→→n{pp}s charge-exchange reaction have been measured at a beam energy of 600 MeV at the COSY-ANKE facility by using an unpolarised proton beam incident on an internal storage cell target filled with polarised deuterium gas. The low energy recoiling protons were measured in a pair of silicon tracking telescopes placed on either side of the target. Putting a cut of 3 MeV on the diproton excitation energy ensured that the two protons were dominantly in the S01 state, here denoted by {pp}s. The polarisation of the deuterium gas was established through measurements in parallel of proton–deuteron elastic scattering. By analysing events where both protons entered the same telescope, the charge-exchange reaction was measured for momentum transfers q≥160 MeV/c. These data provide a good continuation of the earlier results at q≤140 MeV/c obtained with a polarised deuteron beam. They are also consistent with impulse approximation predictions with little sign evident for any modifications due to multiple scatterings. These successful results confirm that the ANKE deuteron charge-exchange programme can be extended to much higher energies with a polarised deuterium target than can be achieved with a polarised deuteron beam.

  4. NUMEN Project @ LNS : Heavy ions double charge exchange reactions towards the 0νββ nuclear matrix element determination

    Energy Technology Data Exchange (ETDEWEB)

    Agodi, C., E-mail: agodi@lns.infn.it; Calabretta, L.; Calanna, A.; Carbone, D.; Cavallaro, M.; Colonna, M.; Cuttone, G.; Finocchiaro, P.; Pandola, L.; Rifuggiato, D.; Tudisco, S. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Cappuzzello, F.; Greco, V. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy); Bonanno, D. L.; Bongiovanni, D. G.; Longhitano, F. [INFN - Sezione di Catania, Catania (Italy); Branchina, V. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy); Foti, A.; Lo Presti, D. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy); INFN - Sezione di Catania, Catania (Italy); Lanzalone, G. [Università di Enna, Enna (Italy); and others

    2015-10-28

    In the NUMEN Project it is proposed an innovative technique to access the nuclear matrix elements entering in the expression of the life-time of the neutrinoless double beta decay, using relevant cross sections of double charge exchange reactions. A key aspect is the use of MAGNEX large acceptance magnetic spectrometer, for the detection of the ejectiles, and of the INFN Laboratori Nazionali del Sud (LNS) K800 Superconducting Cyclotron (CS), for the acceleration of the required high resolution and low emittance heavy-ion beams.

  5. Measurement and study of the differential cross section variations corresponding to the n+p→p+n charge exchange reaction between 1 and 2GeV/c

    International Nuclear Information System (INIS)

    Twenty one differential cross section measurements for the np→pn charge exchange reaction have been carried out at the synchrotron Saturne (Saclay) for incident neutron momenta between 1 and 2GeV/c by step of 50MeV/c and in the squared four momentum transfer range 02. The results show that the mechanism of π exchange in the t-channel is clearly present at all the incident momenta; that is confirmed by the agreement with the ''poor man's absorption'' model, based on π exchange, in the range 02. The s dependence of the charge exchange peak shows weak structures which can be associated with the opening of the inelastic channel NΔ(1236) and NN*(1400). The results of an analysis of a set of np→pn amplitudes constructed from NN helicity amplitudes confirm that the π exchange in the t-channel is dominant in the charge exchange reaction

  6. Study of charged current reactions induced by muon antineutrinos

    International Nuclear Information System (INIS)

    We present in this work a study of antineutrino reactions on light targets. We have used the Gargamelle cloud chamber with a propane-freon mix. In the 2 first chapters we give a brief description of the experimental setting and we present the selection criteria of the events. In the third chapter we analyse the data for the reaction anti-ν + p → μ+ + n that preserves strangeness. We have deduced the values of the axial (MA) and vector (MV) form factors: MA = (O.92 ± 0.08) GeV and MV = (0.86 ± 0.04) GeV. In the fourth chapter we study reactions in which strange particles appear (ΔS = 1) and we have determined their production cross-sections. The elastic reaction: anti-ν + p → μ+ + Λ is studied in a more accurate manner thanks to a 3-constraint adjustment that enables the selection of events occurring on free protons. We have deduced from our data the longitudinal, orthogonal and transverse polarization of Λ, we have got respectively Pl = -0.06 ± 0.44; Pp = 0.29 ± 0.41; Pt 1.05 ± 0.30. We have also deduced the values of the total cross-section as a function of the incident antineutrino energy E: σ (0.27 ± 0.02)*E*10-38 cm-2. E has been assessed from the energy deposited in the cloud chamber and we have adjusted the cross-section with a straight line as it is expected under the assumption of scale invariance. (A.C.)

  7. Quasielastic production of polarized hyperons in antineutrino--nucleon reactions

    CERN Document Server

    Akbar, F; Athar, M Sajjad; Singh, S K

    2016-01-01

    We have studied the longitudinal and perpendicular polarizations of final hyperon($\\Lambda$,$\\Sigma$) produced in the antineutrino induced quasielastic charged current reactions on nucleon targets. The nucleon-hyperon transition form factors are determined from the experimental data on quasielastic $(\\Delta S =0)$ charged current (anti)neutrino--nucleon scattering and the semileptonic decay of neutron and hyperons assuming G--invariance, T--invariance and SU(3) symmetry. The vector transition form factors are obtained in terms of nucleon electromagnetic form factors for which various parameterizations available in literature have been used. A dipole parameterization for the axial vector form factor and the pseudoscalar transition form factor derived in terms of axial vector form factor assuming PCAC and GT relation extended to strangeness sector have been used in numerical evaluations. The flux averaged cross section and polarization observables corresponding to CERN Gargamelle experiment have been calculated...

  8. Charge exchange system

    Science.gov (United States)

    Anderson, Oscar A.

    1978-01-01

    An improved charge exchange system for substantially reducing pumping requirements of excess gas in a controlled thermonuclear reactor high energy neutral beam injector. The charge exchange system utilizes a jet-type blanket which acts simultaneously as the charge exchange medium and as a shield for reflecting excess gas.

  9. Interference effects in inclusive charge-exchange p+p→n+X and n+p→p+X reactions at intermediate energies

    International Nuclear Information System (INIS)

    The formalism of Feynman diagrams to describe charge-exchange reactions p+p→n+X and n+p→p+X on a free proton target taking into account spectator and decay modes in the π+ρ+g'-model have used. It is shown that the interference between these modes depends on the set of vertex function parameters used. It is also shown that the constructive interference of the Δ+ and Δ0-isobars is important. 22 refs.; 10 figs

  10. $\\beta$- decay of $^{58}$Zn. A critical test for the charge-exchange reaction as a probe for the $\\beta$- decay strength distribution

    CERN Multimedia

    2002-01-01

    % IS353 \\\\ \\\\ Due to its importance in fundamental physics and astrophysics, a great effort both theoretically and experimentally is devoted to study Gamow Teller (GT)-strength. The GT-strength and its distribution play a key role in late stellar evolution. During the pre-supernova core-collapse of massive stars, the electron capture and nuclear $\\beta$ -decay determine the electron-to-baryon ratio, which influences the infall dynamics and the mass of the final core. The cross-section of the charge-exchange reaction at forward angles with energies above 100~MeV is expected to be proportional to the squares of Fermi and GT matrix elements. This proportionality should provide a Q-value free method to probe the weak interaction strength and renormalization effects in nuclei. Thus charge-exchange reactions are often used to determine the experimental GT-strength. However, the connection between the GT-strength and the cross-section of the charge-exchange reaction is partially model-dependent and the question aris...

  11. Study of the $\\vec{p}d \\to n\\{pp\\}_{s}$ charge-exchange reaction using a polarised deuterium target

    CERN Document Server

    Gou, B; Bagdasarian, Z; Barsov, S; Chiladze, D; Dymov, S; Engels, R; Gaisser, M; Gebel, R; Grigoryev, K; Hartmann, M; Kacharava, A; Khoukaz, A; Kulessa, P; Kulikov, A; Lehrach, A; Li, Z; Lomidze, N; Lorentz, B; Macharashvili, G; Merzliakov, S; Mielke, M; Mikirtychyants, M; Mikirtychyants, S; Nioradze, M; Ohm, H; Prasuhn, D; Rathmann, F; Serdyuk, V; Seyfarth, H; Shmakova, V; Ströher, H; Tabidze, M; Trusov, S; Tsirkov, D; Uzikov, Yu; Valdau, Yu; Wang, T; Weidemann, C; Wilkin, C; Yuan, X

    2014-01-01

    The vector and tensor analysing powers, $A_y$ and $A_{yy}$, of the $\\vec{p}d \\to n\\{pp\\}_{s}$ charge-exchange reaction have been measured at a beam energy of 600 MeV at the COSY-ANKE facility by using an unpolarised proton beam incident on an internal storage cell target filled with polarised deuterium gas. The low energy recoiling protons were measured in a pair of silicon tracking telescopes placed on either side of the target. Putting a cut of 3 MeV on the diproton excitation energy ensured that the two protons were dominantly in the $^{1}S_{0}$ state, here denoted by $\\{pp\\}_{s}$. The polarisation of the deuterium gas was established through measurements in parallel of proton-deuteron elastic scattering. By analysing events where both protons entered the same telescope, the charge-exchange reaction was measured for momentum transfers $q\\geq 160$ MeV/$c$. These data provide a good continuation of the earlier results at $q\\leq 140$ MeV/$c$ obtained with a polarised deuteron beam. They are also consistent wi...

  12. Inclusive measurement of (p,πsup(-)xn) double charge exchange reactions on bismuth from threshold to 800 MeV

    International Nuclear Information System (INIS)

    The energy dependence of the total angle-integrated cross section for the production of astatine isotopes from (p,πsup(-)xn) double charge exchange reactions on bismuth (sup(209)Bi) was measured from 120 to 800 MeV using activation and radiochemical techniques. Chemical yields were estimated by direct radioassaying of sup(211)At activity in thin (approximately 1 mg/cmsup(2)), irradiated bismuth targets. Calculations of the contributions of secondary (2-step) reactions to these measured astatine yields were performed, based partially upon the observed sup(211)At activity although even at the highest energies, the contribution to products lighter than sup(207)At was negligible. These data for products with as many as 7 neutrons removed from the doubly coherent product (sup(210)At) display nearby gaussian shapes for the mass distributions of the astatine residues with the maximum occurring for about sup(204)At. The most probable momentum transfer deduced from these distributions for the initial πsup(-) production step was 335 MeV/c. The observed excitation functions display a behaviour similar to that observed for the yield of sup(210)Po from a (p,πsup(O)) reaction on sup(209)Bi, but radically different from that observed for inclusive πsup(-) reactions on a heavy nucleus. These data are discussed in terms of recent theoretical approaches to negative pion production from bismuth. In addition, a simple, schematic model is developed to treat the rapidly decreasing percentage of the total inclusive πsup(-) emission which is observed for this double charge exchange reaction. This model reflects the capacity of a nucleus to a source of internal energetic protons

  13. Positive-pion double-charge-exchange reaction: experiments on the isotopic pairs oxygen-16,18 and magnesium-24,26

    International Nuclear Information System (INIS)

    The (π+,π-) double-charge-exchange (DCX) reaction has been performed on targets of T = 0,1 isospin (and isotopic) pairs 1618O and 2426Mg. Energy excitation functions of d sigma/d Ω, across the (3,3) π-N resonance, are presented for transitions to double-isobaric analog state (DIAS) and non-DIAS ground-state residual nuclei. Angular distributions in the region of 50 to 330 are presented for the DIAS from the T = 1 nuclei. The similarities and differences of DIAS and non-DIAS distributions are discussed in relation to reaction-mechanism and nuclear-structure effects. Also, a simple, two-amplitude model for the 18O excitation function, consistent with the data, is presented. The utility of DCX in nuclear mass measurements is discussed, with some examples

  14. Positive-pion double-charge-exchange reaction: experiments on the isotopic pairs oxygen-16,18 and magnesium-24,26

    Energy Technology Data Exchange (ETDEWEB)

    Greene, S.J.

    1981-06-01

    The (..pi../sup +/,..pi../sup -/) double-charge-exchange (DCX) reaction has been performed on targets of T = 0,1 isospin (and isotopic) pairs /sup 16/ /sup 18/O and /sup 24/ /sup 26/Mg. Energy excitation functions of d sigma/d ..cap omega.., across the (3,3) ..pi..-N resonance, are presented for transitions to double-isobaric analog state (DIAS) and non-DIAS ground-state residual nuclei. Angular distributions in the region of 5/sup 0/ to 33/sup 0/ are presented for the DIAS from the T = 1 nuclei. The similarities and differences of DIAS and non-DIAS distributions are discussed in relation to reaction-mechanism and nuclear-structure effects. Also, a simple, two-amplitude model for the /sup 18/O excitation function, consistent with the data, is presented. The utility of DCX in nuclear mass measurements is discussed, with some examples.

  15. Expressions for Form Factors for Inelastic Scattering and Charge Exchange in Plane-Wave, Distorted-Wave, and Coupled-Channels Reaction Formalisms

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, F S

    2006-09-25

    This document is intended to facilitate calculation of inelastic scattering and charge-exchange cross sections in a variety of reaction models, including the plane-wave and distorted-wave approximations and the full coupled-channels treatments. Expressions are given for the coupling potentials between the relevant channels in both coordinate and momentum space. In particular, it is expected that the plane-wave calculations should be useful as a check on the correctness of coupled-channels calculations. The Fourier transform methods used to calculate the plane-wave approximation cross sections are also intended to be used to generate the transition potentials for coupled-channels codes, using a folding model with local effective interactions. Specific expressions are given for calculating transition densities for the folding model in the random phase approximation (RPA).

  16. Calculation of reactor antineutrino spectra in TEXONO

    CERN Document Server

    Chen Dong Liang; Mao Ze Pu; Wong, T H

    2002-01-01

    In the low energy reactor antineutrino physics experiments, either for the researches of antineutrino oscillation and antineutrino reactions, or for the measurement of abnormal magnetic moment of antineutrino, the flux and the spectra of reactor antineutrino must be described accurately. The method of calculation of reactor antineutrino spectra was discussed in detail. Furthermore, based on the actual circumstances of NP2 reactors and the arrangement of detectors, the flux and the spectra of reactor antineutrino in TEXONO were worked out

  17. Neutrino and antineutrino induced reactions with nuclei between 1 and 30 GeV

    CERN Document Server

    Lalakulich, O; Mosel, U

    2012-01-01

    Background: Nuclear effects can have a significant impact on neutrino-nucleus interactions. In particular data from neutrino experiments with broad energy distributions require complex theoretical models that are able to take all the relevant channels into account as well as incorporate nuclear effects in both initial and final state interactions. Purpose: We investigate neutrino and antineutrino scattering on iron and carbon in the energy range from 1 to 30 GeV, which is relevant to current and coming experiments (MINOS, NOvA, Minerva). Method: The Giessen Boltzmann--Uehling--Uhlenbeck (GiBUU) model, which implements all reaction channels relevant for neutrino energies under consideration, is used for an investigation of neutrino-nucleus reactions. Results: Our calculations are compared with the recent NOMAD and MINOS data for the integrated inclusive cross sections. Predictions are made for the differential cross sections for semiinclusive final states (pions, kaons, nucleons) for the MINOS and NOvA beams. ...

  18. High-resolution study of the Gamow-Teller strength distribution in the light nuclei 9B and 13N using the (3He,t) charge-exchange reaction at 420 MeV beam energy

    International Nuclear Information System (INIS)

    Excited states in the light nuclei 9B and 13C were studied using the (3He,t) charge-exchange reaction on 9Be and 13C 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 3He 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 (3He,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 13N were studied, and a total of 20 states were observed in 9B. Of these, 9 states in 13C and 10 states in 9B 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 9B and 13N. The only charge-exchange study of 9B 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 9B and determine the B(GT) strength distribution by using recent high-precision beta-decay data. The results point to a strong difference in spatial structure between the low-lying levels of

  19. Study of neutral current reactions with production of a pion induced by muon antineutrinos

    International Nuclear Information System (INIS)

    In this work we have studied the 4 production reactions of a pion induced by muon anti-neutrino collisions with nucleons: anti-νμp → anti-νμpπ0 or anti-νμnπ+ and anti-νμn → anti-νμnπ0 or anti-νμpπ-. We have processed experimental data from the Gargamelle cloud chamber to assess the pion production cross-sections. Our results are consistent with the theoretical predictions of the Adler model and of the Fogli and Nardulli model within the framework of the Weinberg and Salam unified theory. As for the isospin structure of the weak hadronic neutral current, the iso-vectorial component is highlighted in the invariant mass spectra in the channels pπ0 and pπ-. Our results show that the isospin structure is not purely isoscalar or purely iso-vectorial but rather a mix of I = 0 and I = 1. We confirm that the sign of the product of the 2 coupling constants uL*dL is negative. (A.C.)

  20. Systematics of pion double charge exchange

    Energy Technology Data Exchange (ETDEWEB)

    Gilman, R.A.

    1985-10-01

    Differential cross sections have been measured for pion-induced double-charge-exchange (DCX) reactions leading to double-isobaric-analog states (DIAS) and low-lying nonanalog states in the residual nuclei. A description of the experimental details and data analysis is presented. The experimentally observed systematics of reactions leading to DIAS, to nonanalog ground states, and to low-lying 2 states are described. Lowest-order optical-model calculations of DIAS DCX are compared to the data. Efforts to understand the anomalies by invoking additional reaction-mechanism amplitudes and a higher-order optical potential are described. Calculations of nonanalog DCX reactions leading to J/sup / = 0 states were performed within a distorted-wave impulse-approximation framework. The sensitivities of these calculations to input parameters are discussed. 58 refs., 41 figs., 16 tabs.

  1. Probing nuclear correlations with pion-nucleus double charge exchange

    International Nuclear Information System (INIS)

    In this paper we have calculated the lowest order pion double charge reaction mechanism using shell model wavefunctions of medium weight nuclei. We have the sequential reaction mechanism in which the pion undergoes two single-charge exchange scatterings on the valence neutrons. The distortion of the incoming, intermediate, and outgoing pion are included. The closure approximation is made for the intermediate states with an average excitation energy used in the pion propagator. The double-charge exchange is assumed to take place on the valence nucleons which are assumed to be in one spherical shell model orbital. 34 refs., 5 figs., 3 tabs

  2. Impurity charge-exchange processes in Tokamak plasmas

    International Nuclear Information System (INIS)

    Charge-exchange reactions between multiply-charged impurity ions and neutral hydrogen isotopes are considered. Ionization equilibrium and radiative losses are evaluated for oxygen and iron in the presence of either 'thermal' or 'beam' neutrals. The influence of 'thermal' neutrals on recently reported results from ohmically heated TFR discharges is also discussed

  3. Hybrid method to resolve the neutrino mass hierarchy by supernova (anti)neutrino induced reactions

    CERN Document Server

    Vale, D; Paar, N

    2015-01-01

    We introduce a hybrid method to determine the neutrino mass hierarchy by simultaneous measurements of responses of at least two detectors to antineutrino and neutrino fluxes from accretion and cooling phases of core-collapse supernovae. The (anti)neutrino-nucleus cross sections for $^{56}$Fe and $^{208}$Pb are calculated in the framework of the relativistic nuclear energy density functional and weak interaction Hamiltonian, while the cross sections for inelastic scattering on free protons $\\mathrm{p}(\\bar{\

  4. A phenomenological study of the {pi}{sup -} p {yields} {pi}{sup 0} n charge exchange reaction at high energy; Etude phenomenologique de la reaction d`echange de charge {pi}{sup -} p {yields} {pi}{sup 0} n a haute energie

    Energy Technology Data Exchange (ETDEWEB)

    Michaud, Y.

    1995-09-21

    The aim of the study was to examine the behaviour of the proton-proton elastic scattering, for mass center energies around 10 GeV, and more especially to study the charge exchange reaction {pi}{sup -} p {yields} {pi}{sup 0} n for mass center energies between 3 and 20 GeV. A formalism based on the Glauber model has been used, and a Regge trajectory exchange term was introduced in the model in order to enable the description of the lower energy domain (inferior to 10 GeV) that is characterized by a large contribution of meson exchanges at the scattering amplitude. The Glauber model is then applied to the charge exchange reaction and the differential cross section is analyzed for a center mass energy comprised between 3 and 20 GeV, together with the polarization at 40 GeV/c. The approach is then validated through the study of the {pi}{sup -} p {yields} {eta} n reaction. The size of the kernel of proton and pion components implied in the {pi}{sup -} p {yields} {pi}{sup 0} n reaction, is also investigated. 90 refs., 48 figs., 4 tabs., 5 appends.

  5. Charge Exchange Collisions between Ultracold Fermionic Lithium Atoms and Calcium Ions

    CERN Document Server

    Haze, Shinsuke; Saito, Ryoichi; Mukaiyama, Takashi

    2014-01-01

    An observation of charge exchange collisions between ultracold fermionic 6Li atoms and 40Ca+ ions is reported. The reaction product of the charge exchange collision is dentified via mass spectrometry where the motion of the ions is excited parametrically. We measure the cross section of the charge exchange collisions between the 6Li atoms in the ground state and the 40Ca+ ions in the ground and metastable excited states. Investigation of the inelastic collision characteristics in the atom-ion mixture is an important step toward ultracold chemistry based on ultracold atoms and ions.

  6. Double charge exchange at high impact energies

    Science.gov (United States)

    Belkić, Dževad

    1994-03-01

    In fast ion-atom collisions, double ionization always dominates the two-electron transfer. For this reason, an adequate description of double charge exchange requires proper inclusion of intermediate ionization channels. This is even more important in two- than in one-electron transitions. First-order Born-type perturbation theories ignore throughout these electronic continuum intermediate states and hence provide utterly unreliable high energy cross sections for two-electron capture processes. Therefore, it is essential to use second- and higher-order theories, which include the intermediate ionization continua of the two electrons in an approximate manner. In the present paper, a new second-order theory called the Born distorted wave (BDW) approximation is introduced and implemented in the case of symmetric resonant double electron capture from the ground state of helium by fast alpha particles. A genuine four-body formalism is adopted, in contrast to the conventional independent particle model of atomic scattering theory. The obtained results for the total cross sections are compared with the available experimental data, and satisfactory agreement is recorded. As the incident energy increases, a dramatic improvement is obtained in going from the CB1 to the BDW approximation, since the latter closely follows the measurement, whereas the former overestimates the observed total cross sections by two orders of magnitude. This strongly indicates that the role of continuum intermediate states is decisive, even at those incident energies for which the Thomas double scattering effects are not important. This is in sharp contrast to the case of one-electron transfer atomic reactions.

  7. Pion double charge exchange and nuclear structure

    International Nuclear Information System (INIS)

    Pion double charge exchange to both the double-analog state and the ground state is studied for medium weight nuclei. The relative cross section of these two transitions and the importance of nuclear structure as a function of pion kinetic energy is examined. 16 figs., 5 tabs

  8. Charge exchange between hydrogen atoms and fully stripped heavy ions

    International Nuclear Information System (INIS)

    Charge exchange between multicharged ions and background atomic and molecular gases represents one of the limitations to the attainment of high charge states in heavy ion sources, particularly containment sources. An attempt is made to study systematically a particularly simple but in many respects representative class of such reactions, namely charge transfer between atomic hydrogen and fully stripped heavy ions. Approximate cross sections for these processes in the low keV range of collision energies were obtained using a multistate Landau--Zener method. The energy and Z dependences of the cross sections are discussed

  9. Dissociative charge exchange of H2+

    International Nuclear Information System (INIS)

    This thesis is devoted to molecular dissociation, in particular the dissociation of the hydrogen molecule H2 arising from electron capture of its ion H2+ in a collision. Thereby the important practical question how a chemical bond can be broken is implicitly addressed. This thesis opens (chapter I) with an overview of the available experimental approaches in molecular physics. Further the simple Demkov model for NRCE is described. In chapter II a novel experimental technique for measurements on dissociative processes is introduced which combines a high efficiency with a high energy resolution. A detailed description of the techniques applied in the detector, which has a high spatial and timing resolution with 30 μm and 350 psec FWHM respectively for the detection of one particle, is given in chapter III. A semi-classical theory for NRCE in the medium energy range between a diatomic molecular ion and an atom is developed in chapter IV. The experiments on dissociative charge exchange of H2+ with Ar, Mg, Na and Cs targets at keV energies are described in Chapter V. The predissociation of the c3PIsub(u)-state of H2 populated after charge exchange of H2 with several targets at keV energies; is the subject of chapter VI. In chapter VII, orientational oscillations in the cross section for charge exchange of H2+ with alkali targets are discussed. The last chapter deals with predissociation of highly excited states in H2. (Auth.)

  10. Production of antihydrogen via double charge exchange

    International Nuclear Information System (INIS)

    Spectroscopy of the 1S-2S transition of antihydrogen confined in a neutral atom trap and comparison with the equivalent spectral line in hydrogen will provide an accurate test of CPT symmetry and the first one in a mixed baryon-lepton system. Also, with neutral antihydrogen atoms, the gravitational interaction between matter and antimatter can be tested unperturbed by the much stronger Coulomb forces. Antihydrogen is regularly produced at CERN's Antiproton Decelerator by three-body-recombination (TBR) of one antiproton and two positrons. The method requires injecting antiprotons into a cloud of positrons, which raises the average temperature of the antihydrogen atoms produced way above the typical 0.5 K trap depths of neutral atom traps. Therefore only very few antihydrogen atoms can be confined at a time. Precision measurements, like laser spectroscopy, will greatly benefit from larger numbers of simultaneously trapped antihydrogen atoms. Therefore, the ATRAP collaboration developed a different production method that has the potential to create much larger numbers of cold, trappable antihydrogen atoms. Positrons and antiprotons are stored and cooled in a Penning trap in close proximity. Laser excited cesium atoms collide with the positrons, forming Rydberg positronium, a bound state of an electron and a positron. The positronium atoms are no longer confined by the electric potentials of the Penning trap and some drift into the neighboring cloud of antiprotons where, in a second charge exchange collision, they form antihydrogen. The antiprotons remain at rest during the entire process, so much larger numbers of trappable antihydrogen atoms can be produced. Laser excitation is necessary to increase the efficiency of the process since the cross sections for charge-exchange collisions scale with the fourth power of the principal quantum number n. This method, named double charge-exchange, was demonstrated by ATRAP in 2004. Since then, ATRAP constructed a new combined

  11. Study of the elastic scattering and of the (p,n) charge exchange reaction with neutron-rich light exotic beams; Etude de la diffusion elastique et de la reaction d`echange de charge (p,n) avec des faisceaux exotiques legers riches en neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Cortina Gil, D.

    1996-07-05

    We have measured at GANIL, with the high resolution spectrometer SPEG, the elastic scattering of several neutron rich secondary beams ({sup 6}He, {sup 10}Be and {sup 11}Be) on a polypropylene target and the charge exchange reaction p({sup 6}He, {sup 6}Li)n. These exotic beams were produced by nuclear fragmentation and re-focalized with the SISSI device (superconducting solenoids). The signature of a halo structure in these nuclei has been analysed. Special attention has been paid to several aspects of the associated calculations namely, the proton and neutron density distributions and the small binding energy for the last nucleons in these exotic nuclei. Break-up mechanisms are seen to play an important role in these nuclei. 100 refs.

  12. Anatomy of charge-exchange straggling

    International Nuclear Information System (INIS)

    We have studied charge-exchange straggling theoretically for swift krypton and silicon ions and five target gases in the MeV/u energy regime. We find a pronounced two-peak structure for all ion-target combinations. The peak at the highest energy appears around the velocity where the bare ion and the one-electron ion are equally abundant in the equilibrium charge distribution. Correspondingly, the low-energy peak appears near the cross-over between the charge fractions of the two- and the three-electron ion. The possibility of further peaks at lower energies is discussed. Our findings are compared with recent experimental results on straggling of krypton beams

  13. Charge exchange recombination x-ray laser

    International Nuclear Information System (INIS)

    A recombining plasma x-ray laser using charge exchange recombination (CXR) is proposed. Fully stripped carbon ions collide with neutral He atoms and become excited hydrogenlike carbon ions, in which the excited levels with n=3 or 4 are mainly populated. We calculate the gain coefficients of the Balmer α and the Lyman β line of the hydrogenlike carbon ions by the use of a collisional-radiative model in which the CXR process is included. The calculated result shows that substantial gain can be generated for the Lyman β and Balmer α lines and that the gain of the Balmer α line can be strongly enhanced by the effect of CXR. We also report a preliminary experiment of this scheme. (author)

  14. Laboratory simulation of charge exchange-produced X-ray emission from comets.

    Science.gov (United States)

    Beiersdorfer, P; Boyce, K R; Brown, G V; Chen, H; Kahn, S M; Kelley, R L; May, M; Olson, R E; Porter, F S; Stahle, C K; Tillotson, W A

    2003-06-01

    In laboratory experiments using the engineering spare microcalorimeter detector from the ASTRO-E satellite mission, we recorded the x-ray emission of highly charged ions of carbon, nitrogen, and oxygen, which simulates charge exchange reactions between heavy ions in the solar wind and neutral gases in cometary comae. The spectra are complex and do not readily match predictions. We developed a charge exchange emission model that successfully reproduces the soft x-ray spectrum of comet Linear C/1999 S4, observed with the Chandra X-ray Observatory.

  15. Laboratory simulation of charge exchange-produced X-ray emission from comets.

    Science.gov (United States)

    Beiersdorfer, P; Boyce, K R; Brown, G V; Chen, H; Kahn, S M; Kelley, R L; May, M; Olson, R E; Porter, F S; Stahle, C K; Tillotson, W A

    2003-06-01

    In laboratory experiments using the engineering spare microcalorimeter detector from the ASTRO-E satellite mission, we recorded the x-ray emission of highly charged ions of carbon, nitrogen, and oxygen, which simulates charge exchange reactions between heavy ions in the solar wind and neutral gases in cometary comae. The spectra are complex and do not readily match predictions. We developed a charge exchange emission model that successfully reproduces the soft x-ray spectrum of comet Linear C/1999 S4, observed with the Chandra X-ray Observatory. PMID:12791989

  16. Fine structure of charge exchange lines observed in laboratory plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Ida, K.; Nishimura, S. [National Inst. for Fusion Science, Nagoya (Japan); Kondo, K.

    1997-01-01

    The influence of the fine structure of charge exchange lines appears only at the plasma edge or in the recombining phase where the ion temperature is low enough. The observed spectra in Li III and C VI are consistent with the sum of fine-structure components populated by statistical weights (assuming complete l-mixing) not by direct charge exchange cross sections. Some discrepancy was observed in the intensity ratio of fine-structure components between the observation and calculation for C VI in the recombining phase. The fine-structure of charge exchange lines gives an apparent Doppler shift in plasma rotation velocity measurement using charge exchange spectroscopy. (author)

  17. Antiproton small momentum transfer charge exchange scattering on protons at 30 GeV/c

    International Nuclear Information System (INIS)

    Antiproton charge exchange scattering on protons anti pp→anti nn is investigated with 30 GeV/c antiprotons at the IHEP accelerator. The experiment confirms the existence of a structure at small angles in the angular distribution of this reaction at high energies, observed earlier

  18. Meson exchange currents in pion double charge exchange at high energies

    CERN Document Server

    Alvarez-Ruso, L

    1995-01-01

    In this letter we study the high energy behavior of the forward differential cross section for the O(18)(pi+,pi-)Ne(18) double charge exchange reaction. We have evaluated the sequential and the meson exchange current mechanisms. The meson exchange current contribution shows a very weak energy dependence and becomes dominant at incident pion kinetic energies above 600 MeV.

  19. Suzaku Observations of Charge Exchange Emission from Solar System Objects

    Science.gov (United States)

    Ezoe, Y.; Fujimoto, R.; Yamasaki, N. Y.; Mitsuda, K.; Ohashi, T.; Ishikawa, K.; Oishi, S.; Miyoshi, Y; Terada, N.; Futaana, Y.; Porter, F. S.; Brown, G. V.

    2012-01-01

    Recent results of charge exchange emission from solar system objects observed with the Japanese Suzaku satellite are reviewed. Suzaku is of great importance to investigate diffuse X-ray emission like the charge exchange from planetary exospheres and comets. The Suzaku studies of Earth's exosphere, Martian exosphere, Jupiter's aurorae, and comets are overviewed.

  20. High flux lithium antineutrino source with variable hard spectrum

    CERN Document Server

    Lyashuk, V I

    2016-01-01

    The high flux antineutrino source with hard antineutrino spectrum based on neutron activation of 7Li and subsequent fast beta-decay (T 1/2 = 0.84 s) of the 8Li isotope with emission of antineutrino with energy up to 13 MeV - is discussed. Creation of the intensive isotope neutrino source of hard spectrum will allow to increase the detection statistics of neutrino interaction and it is especially urgent for oscillation experiments. The scheme of the proposed neutrino source is based on the continuous transport of the created 8Li to the neutrino detector, which moved away from the place of neutron activation. Analytical expressions for lithium antineutrino flux is obtained. The discussed source will ensure to increase the cross section for reactions with deuteron from several times to tens compare to the reactor antineutrino spectrum. An another unique feature of the installation is the possibility to vary smoothly the hardness of the antineutrino spectrum.

  1. Proceedings of the LAMPF workshop on pion double charge exchange

    International Nuclear Information System (INIS)

    Experimental and theoretical aspects of double-analog, nonanalog, and continuum pion double charge exchange in the 50- to 310-MeV energy range are covered. Separate abstracts were prepared for 22 papers in these proceedings

  2. Electronic device for measuring the polarization parameter in the {pi}{sup -}p {yields} {pi}{sup 0}n charge exchange reaction on a polarized proton target; Un appareillage electronique destine a la mesure du parametre de polarisation dans la reaction d'echange de charge {pi}{sup -}p {yields} {pi}{sup 0}n sur cible de protons polarises

    Energy Technology Data Exchange (ETDEWEB)

    Brehin, S. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-12-15

    An electronic apparatus has been constructed to measure the polarization parameter P{sub 0}(t) in {pi}{sup -}p {yields} {pi}{sup 0}n charge exchange scattering at 5.9 GeV/c and 11,2 GeV/c on polarized proton target. This device insures triggering of a heavy plate spark chamber, allowing visualisation of {gamma} rays from the {pi}{sup 0} decays when the associated neutron offers suitable characteristics in direction and energy. The neutron is detected by an array of 32 counters and his energy is measured by a time of flight method. Electronic circuits of this apparatus are described as test and calibration methods used. (author) [French] Un appareillage electronique a ete realise pour mesurer le parametre de polarisation P{sub 0}(t) dans la reaction d'echange de charge {pi}{sup -}p {yields} {pi}{sup 0}n a 5,9 GeV/c et 11,2 GeV/c sur une cible de protons polarises. Ce dispositif assure le declenchement d'une chambre a etincelles a plaques lourdes, permettant de visualiser les {gamma} de desitegration du {pi}{sup 0}, lorsque le neutron associe presente les caracteristiques convenables en direction et en energie. Le neutron est detecte par un ensemble de 32 compteurs et son energie est mesuree par une methode de temps de vol. Les circuits composant cet appareillage sont decrits ainsi que les methodes d'etalonnage et de verification utilisees. (auteur)

  3. Terrestrial and Reactor Antineutrinos in Borexino

    Science.gov (United States)

    Chen, M. C.; Calaprice, F. P.; Rothschild, C. G.

    1998-10-01

    The Earth is an abundant source of antineutrinos coming from the decay of radioactive elements in the mantle and crust. Detecting these antineutrinos is a challenge due to their small cross section and low energies. The Borexino solar neutrino experiment will also be an excellent detector for barν_e. With 300 tons of ultra-low-background liquid scintillator, surrounded by an efficient muon veto, the inverse-β-decay reaction: barνe + p arrow e^+ + n (Q = 1.8 MeV), can be exploited to detect terrestrial antineutrinos from the uranium and thorium decay chains, with little background. A direct measurement of the total uranium and thorium abundance would establish important geophysical constraints on the heat generation and thermal history of the Earth. Starting with the most recent uranium and thorium distribution and abundance data, and employing a global map of crustal type and thickness, we calculated the antineutrino fluxes for several sites. We estimate a terrestrial antineutrino event rate in Borexino of 10 events per year. This small signal can be distinguished over the neutrino background from the world's nuclear power reactors by measuring the positron energy spectrum from the barνe events. The possibility to perform a long-baseline oscillation experiment, reaching Δ m^2 ≈ 10-6 eV^2, using the nuclear reactors in Europe will also be discussed.

  4. Charge exchange between singly ionized helium ions

    International Nuclear Information System (INIS)

    The plane-wave Born approximation was used to evaluate the charge transfer cross sections for the reaction He+ + He+ → He++ + He. The charge transfer cross section is graphed as a function of incident energy and compared with experimental measurements

  5. Controlled charge exchange between alkaline earth metals and their ions

    Science.gov (United States)

    Gacesa, Marko; Côté, Robin

    2015-05-01

    We theoretically investigate the prospects of realizing controlled charge exchange via magnetic Feshbach resonances in cold and ultracold collisions of atoms and ions. In particular, we focus on near-resonant charge exchange in heteroisotopic combinations of alkaline earth metals, such as 9Be++10 Be9 Be+10Be+ , which exhibit favorable electronic and hyperfine structure. The quantum scattering calculations are performed for a range of initial states and experimentally attainable magnetic fields in standard coupled-channel Feshbach projection formalism, where higher-order corrections such as the mass-polarization term are explicitely included. In addition, we predict a number of magnetic Feshbach resonances for different heteronuclear isotopic combinations of the listed and related alkaline earth elements. Our results imply that near-resonant charge-exchange could be used to realize atom-ion quantum gates, as well as controlled charge transfer in optically trapped cold quantum gases. This work is partially supported by ARO.

  6. Charge exchange X-rays from the heliosheath

    Science.gov (United States)

    Medvedev, M. V.; Robertson, I. P.; Cravens, T. E.; Zank, G. P.; Florinski, V.

    2006-09-01

    X-rays are produced throughout the heliosphere as a consequence of charge transfer collisions between heavy solar wind ions and neutral atoms. After such a collision the solar wind ion is left in a highly excited state and emits extreme ultraviolet and soft X-ray photons. In the outer heliosphere, solar wind charge exchange X-ray emission is mainly due to charge exchange with neutral interstellar hydrogen. We have combined MHD simulations with a comprehensive charge exchange computation code. We trace the full evolution of solar wind ions along stream line in order to produce three-dimensional emissivities and, subsequently, two-dimensional X-ray brightness and spectral maps of the heliosphere as would be observed from the outside. The model treats both the collisionally thin and the collisionally thick regimes. This model can be a diagnostic tool for studying stellar wind properties of nearby Sun-like stars.

  7. Resonance charge exchange mechanism at high and moderate energies

    Energy Technology Data Exchange (ETDEWEB)

    Bogdanov, A.V.; Gevorkyan, A.S.

    1984-03-01

    Charge exchange mechanisms at high and medium energies are investigated, taking the resonance charge exchange of a proton by an hydrogen atom as an example. It is established that there are two classical charge exchange mechanisms related to direct proton knockout from the bound state and one quantum-mechanical mechanism corresponding to the electron tunnelling from one bound state to another. The classical cross-section diverges for two of these mechanisms, and the quasiclassical scattering amplitude must be calculated on the base of a complex classical trajectory. Physical grounds for the choice of such trajectories are discussed and calculations of the Van Vleck determinant for these mechanisms are presented. Contributions from different mechanisms to the total charge excha nge cross-section are analyzed. A comparison with experimental data and results of other authors is made.

  8. Resonant charge exchange mechanisms at high and moderate energies

    Energy Technology Data Exchange (ETDEWEB)

    Bogdanov, A.V.; Gevorkyan, A.S.

    1984-03-01

    Charge transfer mechanisms at high and moderate energies are considered for the case of resonant charge exchange of a proton on a hydrogen atom. It is shown that there are two classical charge exchange mechanisms associated with direct ejection of a proton from a bound state, and one quantum mechanical mechanism, in which an electron goes from one bound state into another. The classical cross section diverges for two of these mechanisms, and the semiclassical scattering amplitude must be calculated using the complex classical trajectory. The physical premises for choosing these trajectories are discussed and calculations of the Van Vleck determinant for the mechanisms are presented. The relative contributions of the various mechanisms to the total charge exchange cross section are analyzed, and the results are compared with other experimental data.

  9. Measurement of pion double charge exchange on carbon-13, carbon-14, magnesium-26, and iron-56

    Energy Technology Data Exchange (ETDEWEB)

    Seidl, P.A.

    1985-02-01

    Cross sections for the /sup 13,14/C,/sup 26/Mg,/sup 56/Fe(..pi../sup +/,..pi../sup -/)/sup 13,14/O,/sup 26/Si,/sup 56/Ni reactions were measured with the Energetic Pion Channel and Spectrometer at the Clinton P. Anderson Meson Physics Facility for 120 less than or equal to T/sub ..pi../ less than or equal to 292 MeV and 0 less than or equal to theta less than or equal to 50. The double isobaric analog states (DIAS) are of primary interest. In addition, cross sections for transitions to /sup 14/O(0/sup +/, 5.92 MeV), /sup 14/O(2/sup +/, 7.77 MeV), /sup 56/Ni(gs), /sup 13/O(gs), and /sup 13/O(4.21 MeV) are presented. The /sup 13/O(4.21 MeV) state is postulated to have J/sup ..pi../ = 1/2/sup -/. The data are compared to previously measured double-charge-exchange cross sections on other nuclei, and the systematics of double charge exchange on T greater than or equal to 1 target nuclei leading to the DIAS are studied. Near the ..delta../sub 33/ resonance, cross sections for the DIAS transitions are in disagreement with calculations in which the reaction is treated as sequential charge exchange through the free pion-nucleon amplitude, while for T/sub ..pi../ > 200 MeV the anomalous features of the 164 MeV data are not apparent. This is evidence for significant higher order contributions to the double-charge-exchange amplitude near the reasonable energy. Two theoretical approaches that include two nucleon processes are applied to the DIAS data. 64 references.

  10. Characterization of an atomic hydrogen source for charge exchange experiments

    Science.gov (United States)

    Leutenegger, M. A.; Beiersdorfer, P.; Betancourt-Martinez, G. L.; Brown, G. V.; Hell, N.; Kelley, R. L.; Kilbourne, C. A.; Magee, E. W.; Porter, F. S.

    2016-11-01

    We characterized the dissociation fraction of a thermal dissociation atomic hydrogen source by injecting the mixed atomic and molecular output of the source into an electron beam ion trap containing highly charged ions and recording the x-ray spectrum generated by charge exchange using a high-resolution x-ray calorimeter spectrometer. We exploit the fact that the charge exchange state-selective capture cross sections are very different for atomic and molecular hydrogen incident on the same ions, enabling a clear spectroscopic diagnostic of the neutral species.

  11. Characterization of charge-exchange collisions between ultracold $\\rm{^6Li}$ atoms and $\\rm{^{40}Ca^+}$ ions

    CERN Document Server

    Saito, R; Sasakawa, M; Nakai, R; Raoult, M; Silva, H Da; Dulieu, O; Mukaiyama, T

    2016-01-01

    We investigate the energy dependence and the internal-state dependence of the charge-exchange collision cross sections in a mixture of $^6$Li atoms and $^{40}$Ca$^+$ ions in the collision energy range from 0.2 mK to 1 K. Deliberately excited ion micromotion is used to control the collision energy of atoms and ions. The energy dependence of the charge-exchange collision cross section obeys the Langevin model in the temperature range of the current experiment, and the measured magnitude of the cross section is correlated to the internal state of the $^{40}$Ca$^+$ ions. Revealing the relationship between the charge-exchange collision cross sections and the interaction potentials is an important step toward the realization of the full quantum control of the chemical reactions at an ultralow temperature regime.

  12. CHARGE-EXCHANGE SCATTERING OF NEGATIVE PIONS BY HYDROGEN AT 230,260, 290, 317 AND 371 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Caris, John C

    1960-03-18

    The differential cross section for charge-exchange scattering of negative pions by hydrogen has been observed at 230, 260, 290, 317, and 371 Mev. The reaction was observed by detecting one gamma ray from the {pi}{sup 0} decay with a scintillation-counter telescope.

  13. Charge exchange spectroscopy as a fast ion diagnostic on TEXTOR

    NARCIS (Netherlands)

    Delabie, E.; Jaspers, R. J. E.; von Hellermann, M. G.; Nielsen, S.K.; Marchuk, O.

    2008-01-01

    An upgraded charge exchange spectroscopy diagnostic has been taken into operation at the TEXTOR tokamak. The angles of the viewing lines with the toroidal magnetic field are close to the pitch angles at birth of fast ions injected by one of the neutral beam injectors. Using another neutral beam for

  14. Charge exchange emission from solar wind helium ions

    NARCIS (Netherlands)

    Bodewits, D; Hoekstra, R; Seredyuk, B; McCullough, RW; Jones, GH; Tielens, AGGM

    2006-01-01

    Charge exchange X-ray and far-ultraviolet (FUV) aurorae can provide detailed insight into the interaction between solar system plasmas. Using the two complementary experimental techniques of photon emission spectroscopy and translation energy spectroscopy, we have studied state-selective charge exch

  15. Charge Exchange Spectra of Hydrogenic and He-like Iron

    CERN Document Server

    Wargelin, B J; Neill, P A; Olson, R E; Scofield, J H

    2005-01-01

    We present H-like Fe XXVI and He-like Fe XXV charge-exchange spectra resulting from collisions of highly charged iron with N2 gas at an energy of 10 eV/amu in an electron beam ion trap. Although individual high-n emission lines are not resolved in our measurements, we observe that the most likely level for Fe25+ --> Fe24+ electron capture is n~9, in line with expectations, while the most likely value for Fe26+ --> Fe25+ charge exchange is significantly higher. In the Fe XXV spectrum, the K-alpha emission feature dominates, whether produced via charge exchange or collisional excitation. The K-alpha centroid is lower in energy for the former case than the latter (6666 versus 6685 eV, respectively), as expected because of the strong enhancement of emission from the forbidden and intercombination lines, relative to the resonance line, in charge-exchange spectra. In contrast, the Fe XXVI high-n Lyman lines have a summed intensity greater than that of Ly-alpha, and are substantially stronger than predicted from the...

  16. Charge exchange spectroscopy as a fast ion diagnostic on TEXTOR

    DEFF Research Database (Denmark)

    Delabie, E.; Jaspers, R.J.E.; von Hellermann, M.G.;

    2008-01-01

    An upgraded charge exchange spectroscopy diagnostic has been taken into operation at the TEXTOR tokamak. The angles of the viewing lines with the toroidal magnetic field are close to the pitch angles at birth of fast ions injected by one of the neutral beam injectors. Using another neutral beam...

  17. ({sup 18}O,{sup 18}Ne) double charge-exchange with MAGNEX

    Energy Technology Data Exchange (ETDEWEB)

    Bondí, M.; Cappuzzello, F.; Nicolosi, D.; Tropea, S. [Dipartimento di Fisica e Astrofisica, Universitá degli studi di Catania, Catania, 95100, Italy and Istituto di Fisica Nucleare - Laboratori Nazionali del Sud, Catania, 95100 (Italy); Agodi, C.; Carbone, D.; Cavallaro, M.; Cunsolo, A. [Istituto di Fisica Nucleare - Laboratori Nazionali del Sud, Catania, 95100 (Italy); De Napoli, M.; Foti, A. [Istituto di Fisica Nucleare - Sezione di Catania, Catania, 95100 (Italy)

    2014-05-09

    An experimental study concerning Double Gamow-Teller (DGT) modes in ({sup 18}O,{sup 18}Ne) Double Charge-Exchange reactions has been very recently performed at INFN-LNS laboratory in Catania. The experiment was performed using a {sup 40}Ca solid target and a {sup 18}O Cyclotron beam at 270 MeV incident energy. Charged ejectiles produced in the reaction were momentum analyzed and identified by MAGNEX spectrometer at very forward angles. Preliminary results are presented in the present paper.

  18. Antineutrino Monitoring of Thorium Reactors

    CERN Document Server

    Akindele, Oluwatomi A; Norman, Eric B

    2015-01-01

    Various groups have demonstrated that antineutrino monitoring can be successful in assessing the plutonium content in water-cooled nuclear reactors for nonproliferation applications. New reactor designs and concepts incorporate nontraditional fuels types and chemistry. Understanding how these properties affect the antineutrino emission from a reactor can extend the applicability of antineutrino monitoring.Thorium molten salt reactors (MSR) breed U-233, that if diverted constitute an IAEA direct use material. The antineutrino spectrum from the fission of U-233 has been determined, the feasibility of detecting the diversion of a significant quantity, 8 kg of U-233, within the IAEA timeliness goal of 30 days has been evaluated. The antineutrino emission from a thorium reactor operating under normal conditions is compared to a diversion scenario at a 25 meter standoff by evaluating the daily antineutrino count rate and the energy spectrum of the detected antineutrinos. It was found that the diversion of a signifi...

  19. Measurement of absorption and charge exchange of $\\pi^+$ on carbon

    CERN Document Server

    Ieki, K; Berkman, S; Bhadra, S; Cao, C; de Perio, P; Hayato, Y; Ikeda, M; Kanazawa, Y; Kim, J; Kitching, P; Mahn, K; Nakaya, T; Nicholson, M; Olchanski, K; Rettie, S; Tanaka, H A; Wilking, M J; Tobayama, S; Yamauchi, T; Yen, S; Yokoyama, M

    2015-01-01

    The combined cross section for absorption and charge exchange interactions of positively charged pions with carbon nuclei for the momentum range 200 MeV/c to 300 MeV/c have been measured with the DUET experiment at TRIUMF. The uncertainty is reduced by nearly half compared to previous experiments. This result will be a valuable input to existing models to constrain pion interactions with nuclei.

  20. Charge exchange cooling in the tandem mirror plasma confinement apparatus

    International Nuclear Information System (INIS)

    A method and apparatus are described for cooling a plasma confined in the center mirror cell of the tandem mirror apparatus by injecting cold neutral species of the plasma into at least one mirroring region of the center mirror cell. The cooling is due to the loss of warm charged species through charge exchange with the cold neutral species with resulting diffusion of the warm neutral species out of the plasma

  1. Imaging charge exchange recombination spectroscopy on the TEXTOR tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J [Plasma Research Laboratory, The Australian National University, Canberra 0200 (Australia); Jaspers, R [Eindhoven University of Technology, Eindhoven (Netherlands); Lischtschenko, O; Delabie, E [FOM Institute for Plasma Physics ' Rijnhuizen' , Nieuwegein (Netherlands); Chung, J [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2010-12-15

    We describe the application of a simple spatial-heterodyne coherence-imaging filter for 2D Doppler imaging of charge exchange recombination (CXR) emission from a heating beam in the TEXTOR tokamak. Results obtained by the CXR imaging system are found to be consistent with measurements obtained using a standard multi-channel spectrometer-based system. We describe the system, indicate possible enhancements and future applications for imaging CXRS.

  2. Imaging charge exchange recombination spectroscopy on the TEXTOR tokamak

    Science.gov (United States)

    Howard, J.; Jaspers, R.; Lischtschenko, O.; Delabie, E.; Chung, J.

    2010-12-01

    We describe the application of a simple spatial-heterodyne coherence-imaging filter for 2D Doppler imaging of charge exchange recombination (CXR) emission from a heating beam in the TEXTOR tokamak. Results obtained by the CXR imaging system are found to be consistent with measurements obtained using a standard multi-channel spectrometer-based system. We describe the system, indicate possible enhancements and future applications for imaging CXRS.

  3. Charge Exchange Effect on Space-Charge-Limited Current Densities in Ion Diode

    Institute of Scientific and Technical Information of China (English)

    石磊

    2002-01-01

    The article theoretically studied the charge-exchange effects on space charge limited electron and ion current densities of non-relativistic one-dimensional slab ion diode, and compared with those of without charge exchange.

  4. Systematics of heavy-ion charge-exchange straggling

    Science.gov (United States)

    Sigmund, P.; Schinner, A.

    2016-10-01

    The dependence of heavy-ion charge-exchange straggling on the beam energy has been studied theoretically for several ion-target combinations. Our previous work addressed ions up to krypton, while the present study focuses on heavier ions, especially uranium. Particular attention has been paid to a multiple-peak structure which has been predicted theoretically in our previous work. For high-Z1 and high-Z2 systems, exemplified by U in Au, we identify three maxima in the energy dependence of charge-exchange straggling, while the overall magnitude is comparable with that of collisional straggling. Conversely, for U in C, charge-exchange straggling dominates, but only two peaks lie in the energy range where we presently are able to produce credible predictions. For U-Al we find good agreement with experiment in the energy range around the high-energy maximum. The position of the high-energy peak - which is related to processes in the projectile K shell - is found to scale as Z12 , in contrast to the semi-empirical Z13/2 dependence proposed by Yang et al. Measurements for heavy ions in heavy targets are suggested in order to reconcile a major discrepancy between the present calculations and the frequently-used formula by Yang et al.

  5. Cold neutral atoms via charge exchange from excited state positronium: a proposal

    CERN Document Server

    Bertsche, W A; Eriksson, S

    2016-01-01

    We present a method for generating cold neutral atoms via charge exchange reactions between trapped ions and Rydberg positronium. The high charge exchange reaction cross section leads to efficient neutralisation of the ions and since the positronium-ion mass ratio is small, the neutrals do not gain appreciable kinetic energy in the process. When the original ions are cold the reaction produces neutrals that can be trapped or further manipulated with electromagnetic fields. Because a wide range of species can be targeted we envisage that our scheme may enable experiments at low temperature that have been hitherto intractable due to a lack of cooling methods. We present an estimate for achievable temperatures, neutral number and density in an experiment where the neutrals are formed at a milli-Kelvin temperature from either directly or sympathetically cooled ions confined on an ion chip. The neutrals may then be confined by their magnetic moment in a co-located magnetic minimum well also formed on the chip. We ...

  6. Neutron radiative capture reactions on nuclei of relevance to 0νββ, dark matter and neutrino/antineutrino searches

    Directory of Open Access Journals (Sweden)

    Tornow W.

    2015-01-01

    Full Text Available A program is underway at the Triangle Universities Nuclear Laboratory (TUNL to measure the neutron capture cross section in the 0.5 to 15 MeV energy range on nuclei whose radioactive daughters could potentially create backgrounds in searches for rare events. Here, we refer to neutrino-less double-beta decay and dark-matter searches, and to detectors built for neutrino and/or antineutrino studies. Neutron capture cross-section data obtained by using the activation method are reported for 40Ar, 74,76Ge, 128,130Te and 136Xe and compared to model calculations and evaluations.

  7. Antineutrino analysis for continuous monitoring of nuclear reactors: Sensitivity study

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Christopher; Erickson, Anna [Georgia Institute of Technology, Nuclear and Radiological Engineering, G. W. Woodruff School of Mechanical Engineering, 770 State St. NW, Atlanta, Georgia 30332 (United States)

    2015-10-28

    This paper explores the various contributors to uncertainty on predictions of the antineutrino source term which is used for reactor antineutrino experiments and is proposed as a safeguard mechanism for future reactor installations. The errors introduced during simulation of the reactor burnup cycle from variation in nuclear reaction cross sections, operating power, and other factors are combined with those from experimental and predicted antineutrino yields, resulting from fissions, evaluated, and compared. The most significant contributor to uncertainty on the reactor antineutrino source term when the reactor was modeled in 3D fidelity with assembly-level heterogeneity was found to be the uncertainty on the antineutrino yields. Using the reactor simulation uncertainty data, the dedicated observation of a rigorously modeled small, fast reactor by a few-ton near-field detector was estimated to offer reduction of uncertainty on antineutrino yields in the 3.0–6.5 MeV range to a few percent for the primary power-producing fuel isotopes, even with zero prior knowledge of the yields.

  8. Laser-Assisted H- Charge Exchange Injection in Magnetic Fields

    Energy Technology Data Exchange (ETDEWEB)

    Gorlov, Timofey V [ORNL; Danilov, Viatcheslav V [ORNL; Shishlo, Andrei P [ORNL

    2010-01-01

    The use of stripping foils for charge exchange injection can cause a number of operational problems in high intensity hadron accelerators. A recently proposed three-step method of laser-assisted injection is capable of overcoming these problems. This paper presents advances in the physical model of laser-assisted charge exchange injection of H- beams and covers a wide field of atomic physics. The model allows the calculation of the evolution of an H0 beam taking into account spontaneous emission, field ionization and external electromagnetic fields. Some new data on the hydrogen atom related to the problem are calculated. The numerical calculations in the model use realistic descriptions of laser field and injection beam. Generally, the model can be used for design and optimization of a laser-assisted injection cell within an accelerator lattice. Example calculations of laser-assisted injection for an intermediate experiment at SNS in Oak Ridge and for the PS2 accelerator at CERN are presented. Two different schemes, distinctively characterized by various magnetic fields at the excitation point, are discussed. It was shown that the emittance growth of an injected beam can be drastically decreased by moving excitation point into a strong magnetic field.

  9. Laser-assisted H- charge exchange injection in magnetic fields

    Science.gov (United States)

    Gorlov, T.; Danilov, V.; Shishlo, A.

    2010-05-01

    The use of stripping foils for charge exchange injection can cause a number of operational problems in high intensity hadron accelerators. A recently proposed three-step method of laser-assisted injection is capable of overcoming these problems. This paper presents advances in the physical model of laser-assisted charge exchange injection of H- beams and covers a wide field of atomic physics. The model allows the calculation of the evolution of an H0 beam taking into account spontaneous emission, field ionization, and external electromagnetic fields. Some new data on the hydrogen atom related to the problem are calculated. The numerical calculations in the model use realistic descriptions of laser field and injection beam. Generally, the model can be used for design and optimization of a laser-assisted injection cell within an accelerator lattice. Example calculations of laser-assisted injection for an intermediate experiment at SNS in Oak Ridge and for the PS2 accelerator at CERN are presented. Two different schemes, distinctively characterized by various magnetic fields at the excitation point, are discussed. It was shown that the emittance growth of an injected beam can be drastically decreased by moving the excitation point into a strong magnetic field.

  10. Charge exchange in fluid description of partially ionized plasmas

    CERN Document Server

    Vranjes, J; Luna, M

    2015-01-01

    The effects of charge exchange on waves propagating in weakly ionized plasmas are discussed. It is shown that for low-frequency processes, ions and neutrals should be treated as a single fluid with some effective charge on all of them. We have derived a new momentum equation which should be used in such an environment. As a result, the low-frequency magnetic waves can propagate even if particles are not magnetized, which is entirely due to the charge exchange and the fact that it is not possible to separate particles into two different populations as charged and neutral species. So there can be no friction force between ions and neutrals in the usual sense. The mean force per particle is proportional to the ionization ratio $n_i/(n_i+ n_n)$. Regarding the application of the theory to the Alfven wave propagation in the lower solar atmosphere, the results predict that the plane of displacement of the fluid must change by 90 degrees when an Alfven wave propagates from the area where particles are un-magnetized (...

  11. Relation of isospin-symmetry breaking correction for superallowed beta decay to energy of charge-exchange giant monopole resonance

    CERN Document Server

    Rodin, Vadim

    2012-01-01

    Having applied an analytical transformation, a new exact representation for the nuclear isospin-symmetry breaking correction $\\delta_C$ to superallowed beta decay is obtained. The correction is shown to be essentially reciprocal to the square of an energy parameter $\\Omega_M$ which characterizes charge-exchange monopole strength distribution. The proportionality coefficient in this relation is determined by basic properties of the ground state of the even-even mother nucleus, and should be reliably calculated in any realistic nuclear model. Therefore, the single parameter $\\Omega_M$ contains all the information about the properties of excited $0^+$ states needed to describe $\\delta_C$. This parameter can possibly be determined experimentally by charge-exchange reactions. Basic quantities of interest are calculated within the isospin-consistent continuum random phase approximation, and the values of $\\delta_C$ are compared with the corresponding results by other approaches.

  12. Charge-Exchange Excitation of the Isobaric Analog State and Implication for the Nuclear Symmetry Energy and Neutron Skin

    Science.gov (United States)

    Khoa, Dao T.; Loc, Bui Minh; Zegers, R. G. T.

    The charge-exchange (p, n) or (3He,t) reaction can be considered as elastic scattering of proton or 3He by the isovector term of the optical potential that flips the projectile isospin. Therefore, the accurately measured charge-exchange scattering cross section for the isobaric analog states can be a good probe of the isospin dependence of the optical potential, which is determined exclusively within the folding model by the difference between the neutron and proton densities and isospin dependence of the nucleon-nucleon interaction. On the other hand, the same isospin- and density-dependent nucleon-nucleon interaction can also be used in a Hartree-Fock calculation of asymmetric nuclear matter, to estimate the nuclear matter energy and its asymmetry part. As a result, the fine-tuning of the isospin dependence of the effective nucleon-nucleon interaction against the measured (p, n) or (3He,t) cross sections should allow us to make some realistic prediction of the nuclear symmetry energy and its density dependence. Moreover, given the neutron skin of the target related directly to the neutron-proton difference of the ground-state density, it can be well probed in the analysis of the charge-exchange (3He,t) reactions at medium energies when the two-step processes can be neglected and the t-matrix interaction can be used in the folding calculation.

  13. Charge exchange measurements of ion behavior in the ISX tokamak

    International Nuclear Information System (INIS)

    Analysis of charge exchange neutrals is the standard method for measuring ion behavior in tokamak plasmas. Limitations of this technique, which arise in dense and neutral-beam-heated plasmas, are discussed. Two refinements that address these limitations are described: a neutral particle analyzer, which incorporates both mass and energy resolution to distinguish different ion components such as the fast and thermal ions in beam-heated plasmas, and an improved data analysis procedure, which accounts for the effects of profiles and neutral attenuation in dense plasmas. A simple two-dimensional Monte Carlo neutral transport code was developed and used to investigate the effects of toroidally asymmetric neutral density profiles. Applications of these methods to experiments in the Impurity Study Experiment (ISX) are discussed; they include energy confinement studies on ISX-A, natural beam heating and high beta studies on ISX-B, and pellet fueling studies on ISX-B

  14. Interdefect charge exchange in silicon particle detectors at cryogenic temperatures

    CERN Document Server

    MacEvoy, B; Hall, G; Moscatelli, F; Passeri, D; Santocchia, A

    2002-01-01

    Silicon particle detectors in the next generation of experiments at the CERN Large Hadron Collider will be exposed to a very challenging radiation environment. The principal obstacle to long-term operation arises from changes in detector doping concentration (N/sub eff/), which lead to an increase in the bias required to deplete the detector and hence achieve efficient charge collection. We have previously presented a model of interdefect charge exchange between closely spaced centers in the dense terminal clusters formed by hadron irradiation. This manifestly non-Shockley-Read-Hall (SRH) mechanism leads to a marked increase in carrier generation rate and negative space charge over the SRH prediction. There is currently much interest in the subject of cryogenic detector operation as a means of improving radiation hardness. Our motivation, however, is primarily to investigate our model further by testing its predictions over a range of temperatures. We present measurements of spectra from /sup 241/Am alpha par...

  15. Charge Exchange Losses and Stochastic Acceleration in the Solar Wind

    CERN Document Server

    Kenny, Ciaran

    2016-01-01

    Stochastic acceleration of particles under a pressure balance condition can accommodate the universal $p^{-5}$ spectra observed under many different conditions in the inner heliosphere. In this model, in order to avoid an infinite build up of particle pressure, a relationship between the momentum diffusion of particles and the adiabatic deceleration in the solar wind must exist. This constrains both the spatial and momentum diffusion coefficients and results in the $p^{-5}$ spectrum in the presence of adiabatic losses in the solar wind. However, this theory cannot explain the presence of such spectra beyond the termination shock, where adiabatic deceleration is negligible. To explain this apparent discrepancy, we include the effect of charge exchange losses, resulting in new forms of both the spatial and momentum diffusion coefficients that have not previously been considered. Assuming that the turbulence is of a large-scale compressible nature, we find that a balance between momentum diffusion and losses can...

  16. Charge exchange of a polar molecule at its cation

    International Nuclear Information System (INIS)

    The Landau-Herring method is used to derive an analytic expression for the one-electron exchange interaction of a polar molecule with its positively charged ion, induced by a σ-electron. Analogously to the classical Van der Pole method, the exchange interaction potential is averaged over the rotational states of colliding particles. The resonant charge-transfer cross section is calculated, and the effect of the dipole moments of the core on the cross section is analyzed. It is shown that allowance for the dependence of the exchange potential on the orientation of the dipole moments relative to the molecular axis may change the dependence of the cross section on the velocity of colliding particles, which is typical of the resonant charge exchange, from the resonance to the quasi-resonance dependence.

  17. Reactor monitoring using antineutrino detectors

    Science.gov (United States)

    Bowden, N. S.

    2011-08-01

    Nuclear reactors have served as the antineutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Measurements made with antineutrino detectors could therefore offer an alternative means for verifying the power history and fissile inventory of a reactor as part of International Atomic Energy Agency (IAEA) and/or other reactor safeguards regimes. Several efforts to develop this monitoring technique are underway worldwide.

  18. Charge Exchange Cross Sections Measured at Low Energies in Q-Machines

    DEFF Research Database (Denmark)

    Andersen, S. A.; Jensen, Vagn Orla; Michelsen, Poul

    1972-01-01

    A new technique for measurements of charge exchange cross sections at low energies is described. The measurements are performed in a single‐ended Q machine. The resonance charge exchange cross section for Cs at 2 eV was found to be 0.6×10−13 cm2±20%.......A new technique for measurements of charge exchange cross sections at low energies is described. The measurements are performed in a single‐ended Q machine. The resonance charge exchange cross section for Cs at 2 eV was found to be 0.6×10−13 cm2±20%....

  19. Observation of Large Enhancement of Charge Exchange Cross Sections with Neutron-Rich Carbon Isotopes

    CERN Document Server

    Tanihata, I; Kanungo, R; Ameil, F; Atkinson, J; Ayyad, Y; Cortina-Gil, D; Dillmann, I; Estradé, A; Evdokimov, A; Farinon, F; Geissel, H; Guastalla, G; Janik, R; Knoebel, R; Kurcewicz, J; Litvinov, Yu A; Marta, M; Mostazo, M; Mukha, I; Nociforo, C; Ong, H J; Pietri, S; Prochazka, A; Scheidenberger, C; Sitar, B; Strmen, P; Takechi, M; Tanaka, J; Toki, H; Vargas, J; Winfield, J S; Weick, H

    2015-01-01

    Production cross sections of nitrogen isotopes from high-energy carbon isotopes on hydrogen and carbon targets have been measured for the first time for a wide range of isotopes. The fragment separator FRS at GSI was used to deliver C isotope beams. The cross sections of the production of N isotopes were determined by charge measurements of forward going fragments. The cross sections show a rapid increase with the number of neutrons in the projectile. Since the production of nitrogen is mostly due to charge exchange reactions below the proton separation energies, the present data suggests a concentration of Gamow-Teller and Fermi transition strength at low excitation energies for neutron-rich isotopes. It was also observed that the cross sections were enhanced much more strongly for neutron rich isotopes in the C-target data.

  20. Charge-exchange scattering to the isobaric analog state at medium energies as a probe of the neutron skin

    CERN Document Server

    Loc, Bui Minh; Zegers, R G T

    2014-01-01

    The charge-exchange (3He,t) scattering to the isobaric analog state (IAS) of the target can be considered as "elastic" scattering of 3He by the isovector term of the optical potential (OP) that flips the projectile isospin. Therefore, the accurately measured charge-exchange scattering cross- section for the IAS can be a good probe of the isospin dependence of the OP, which is determined exclusively within the folding model by the difference between the neutron and proton densities and isospin dependence of the nucleon-nucleon interaction. Given the neutron skin of the target is related directly to the same density difference, it can be well probed in the analysis of the charge- exchange (3He,t) reactions at medium energies when the two-step processes can be neglected and the t-matrix interaction can be used in the folding calculation. For this purpose, the data of the (3He,t) scattering to the IAS of 90Zr and 208Pb targets at Elab = 420 MeV have been analyzed in the distorted wave Born approximation using the...

  1. Antineutrino oscillation study in the muon antineutrino → electron antineutrino channel at the Brookhaven accelerator

    International Nuclear Information System (INIS)

    This thesis is devoted to the E816 experiment which looked for (anti)neutrino oscillations. This experiment was performed in the neutrino beam of the Brookhaven AGS during spring 1986. Following a short recall of the theoretical and experimental status, the beam line and the apparatus are described. The analysis is exposed in details with a special emphasis on final states including at least one electromagnetic shower and one prong. Preliminary results have been obtained and show an excess of 23 ±8.7±14.6 events interpreted as charged current antineutrino electron interactions. In terms of a limit we obtain for the probability P(antineutrino muon → antineutrino electron): P<4.4% (95% C.L.)

  2. Long-Term Testing and Properties of Acrylic for the Daya Bay Antineutrino Detectors

    CERN Document Server

    Krohn, M; Heeger, K M

    2012-01-01

    The Daya Bay reactor antineutrino experiment has recently measured the neutrino mixing parameter sin22{\\theta}13 by observing electron antineutrino disappearance over kilometer-scale baselines using six antineutrino detectors at near and far distances from reactor cores at the Daya Bay nuclear power complex. Liquid scintillator contained in transparent target vessels is used to detect electron antineutrinos via the inverse beta-decay reaction. The Daya Bay experiment will operate for about five years yielding a precision measurement of sin22{\\theta}13. We report on long-term studies of poly(methyl methacrylate) known as acrylic, which is the primary material used in the fabrication of the target vessels for the experiment's antineutrino detectors. In these studies, acrylic samples are subjected to gaseous and liquid environmental conditions similar to those experienced during construction, transport, and operation of the Daya Bay acrylic target vessels and detectors. Mechanical and optical stability of the ac...

  3. Charge Exchange, from the Laboratory to Galaxy Clusters

    Science.gov (United States)

    Betancourt-Martinez, Gabriele; Beiersdorfer, Peter; Brown, Gregory; Hell, Natalie; Leutenegger, Maurice A.; Porter, Frederick S.; Reynolds, Christopher S.

    2016-04-01

    X-ray emission due to charge exchange (CX) between solar wind ions and neutrals in comets and planetary atmospheres is ubiquitous in the solar system, and is also a significant foreground in all observations from low-Earth orbit. It is also possible that CX is common astrophysically, in any environment where hot plasma and cold gas interact. A current challenge is that theoretical models of CX spectra do not always accurately describe observations, and require further experimental verification. This is especially important to focus on now, as the recent launch of Astro-H is providing us with the first high-resolution spectra of extended x-ray sources. In order to improve our understanding and modeling of CX spectra, we take advantage of the laboratory astrophysics program at the Lawrence Livermore National Laboratory and use an Electron Beam Ion Trap (EBIT) to perform CX experiments, using the EBIT Calorimeter Spectrometer. We present experimental benchmarks that can be used to develop a more comprehensive and accurate CX theory. On the observational side, we also investigate the possibility of CX occurring in the filaments around the central galaxy of the Perseus cluster, NGC 1275. We use Chandra ACIS data, combined with what we know about laboratory CX spectra, to investigate the possibility of CX being a significant contributor to the x-ray emission.

  4. Charge exchange recombination spectroscopy on the T-10 tokamak.

    Science.gov (United States)

    Klyuchnikov, L A; Krupin, V A; Nurgaliev, M R; Korobov, K V; Nemets, A R; Dnestrovskij, A Yu; Tugarinov, S N; Serov, S V; Naumenko, N N

    2016-05-01

    The charge exchange recombination spectroscopy (CXRS) diagnostics on the T-10 tokamak is described. The system is based on a diagnostic neutral beam and includes three high etendue spectrometers designed for the ITER edge CXRS system. A combined two-channel spectrometer is developed for simultaneous measurements of two beam-induced spectral lines using the same lines of sight. A basic element of the combined spectrometer is a transmitting holographic grating designed for the narrow spectral region 5291 ± 100 Å. The whole CXRS system provides simultaneous measurements of two CXRS impurity spectra and Hα beam line. Ion temperature measurements are routinely provided using the C(6+) CXRS spectral line 5291 Å. Simultaneous measurements of carbon densities and one more impurity (oxygen, helium, lithium etc.) are carried out. Two light collecting systems with 9 lines of sight in each system are used in the diagnostics. Spatial resolution is up to 2.5 cm and temporal resolution of 1 ms is defined by the diagnostic neutral beam diameter and pulse duration, respectively. Experimental results are shown to demonstrate a wide range of the CXRS diagnostic capabilities on T-10 for investigation of impurity transport processes in tokamak plasma. Developed diagnostics provides necessary experimental data for studying of plasma electric fields, heat and particle transport processes, and for investigation of geodesic acoustic modes. PMID:27250422

  5. The Solar Wind Charge-Exchange Production Factor for Hydrogen

    CERN Document Server

    Kuntz, K D; Collier, M R; Connor, H K; Cravens, T E; Koutroumpa, D; Porter, F S; Robertson, I P; Sibeck, D G; Snowden, S L; Thomas, N E; Wash, B M

    2015-01-01

    The production factor, or broad band averaged cross-section, for solar wind charge-exchange with hydrogen producing emission in the ROSAT 1/4 keV (R12) band is $3.8\\pm0.2\\times10^{-20}$ count degree$^{-2}$ cm$^4$. This value is derived from a comparison of the Long-Term (background) Enhancements in the ROSAT All-Sky Survey with magnetohysdrodynamic simulations of the magnetosheath. This value is 1.8 to 4.5 times higher than values derived from limited atomic data, suggesting that those values may be missing a large number of faint lines. This production factor is important for deriving the exact amount of 1/4 keV band flux that is due to the Local Hot Bubble, for planning future observations in the 1/4 keV band, and for evaluating proposals for remote sensing of the magnetosheath. The same method cannot be applied to the 3/4 keV band as that band, being composed primarily of the oxygen lines, is far more sensitive to the detailed abundances and ionization balance in the solar wind. We also show, incidentally,...

  6. Charge exchange spectroscopy as a fast ion diagnostic on TEXTORa)

    Science.gov (United States)

    Delabie, E.; Jaspers, R. J. E.; von Hellermann, M. G.; Nielsen, S. K.; Marchuk, O.

    2008-10-01

    An upgraded charge exchange spectroscopy diagnostic has been taken into operation at the TEXTOR tokamak. The angles of the viewing lines with the toroidal magnetic field are close to the pitch angles at birth of fast ions injected by one of the neutral beam injectors. Using another neutral beam for active spectroscopy, injected counter the direction in which fast ions injected by the first beam are circulating, we can simultaneously measure a fast ion tail on the blue wing of the Dα spectrum while the beam emission spectrum is Doppler shifted to the red wing. An analysis combining the two parts of the spectrum offers possibilities to improve the accuracy of the absolute (fast) ion density profiles. Fast beam modulation or passive viewing lines cannot be used for background subtraction on this diagnostic setup and therefore the background has to be modeled and fitted to the data together with a spectral model for the slowing down feature. The analysis of the fast ion Dα spectrum obtained with the new diagnostic is discussed.

  7. Plasma code for astrophysical charge exchange emission at X-ray wavelengths

    CERN Document Server

    Gu, Liyi; Raassen, A J J

    2016-01-01

    Charge exchange X-ray emission provides unique insights into the interactions between cold and hot astrophysical plasmas. Besides its own profound science, this emission is also technically crucial to all observations in the X-ray band, since charge exchange with the solar wind often contributes a significant foreground component that contaminates the signal of interest. By approximating the cross sections resolved to $n$ and $l$ atomic subshells, and carrying out complete radiative cascade calculation, we create a new spectral code to evaluate the charge exchange emission in the X-ray band. Comparing to collisional thermal emission, charge exchange radiation exhibits enhanced lines from large-$n$ shells to the ground, as well as large forbidden-to-resonance ratios of triplet transitions. Our new model successfully reproduces an observed high-quality spectrum of comet C/2000 WM1 (LINEAR), which emits purely by charge exchange between solar wind ions and cometary neutrals. It demonstrates that a proper charge ...

  8. Plasma code for astrophysical charge exchange emission at X-ray wavelengths

    Science.gov (United States)

    Gu, Liyi; Kaastra, Jelle; Raassen, A. J. J.

    2016-04-01

    Charge exchange X-ray emission provides unique insight into the interactions between cold and hot astrophysical plasmas. Besides its own profound science, this emission is also technically crucial to all observations in the X-ray band, since charge exchange with the solar wind often contributes a significant foreground component that contaminates the signal of interest. By approximating the cross sections resolved to n and l atomic subshells and carrying out complete radiative cascade calculation, we have created a new spectral code to evaluate the charge exchange emission in the X-ray band. Compared to collisional thermal emission, charge exchange radiation exhibits enhanced lines from large-n shells to the ground, as well as large forbidden-to-resonance ratios of triplet transitions. Our new model successfully reproduces an observed high-quality spectrum of comet C/2000 WM1 (LINEAR), which emits purely by charge exchange between solar wind ions and cometary neutrals. It demonstrates that a proper charge exchange model will allow us to probe the ion properties remotely, including charge state, dynamics, and composition, at the interface between the cold and hot plasmas.

  9. AGM2015: Antineutrino Global Map 2015

    CERN Document Server

    Usman, Shawn M; Dye, Stephen T; McDonough, William F; Learned, John G

    2015-01-01

    Every second greater than $10^{25}$ antineutrinos radiate to space from Earth, shining like a faint antineutrino star. Underground antineutrino detectors have revealed the rapidly decaying fission products inside nuclear reactors, verified the long-lived radioactivity inside our planet, and informed sensitive experiments for probing fundamental physics. Mapping the anisotropic antineutrino flux and energy spectrum advance geoscience by defining the amount and distribution of radioactive power within Earth while critically evaluating competing compositional models of the planet. We present the Antineutrino Global Map 2015 (AGM2015), an experimentally informed model of Earth's surface antineutrino flux over the 0 to 11 MeV energy spectrum, along with an assessment of systematic errors. The open source AGM2015 provides fundamental predictions for experiments, assists in strategic detector placement to determine neutrino mass hierarchy, and aids in identifying undeclared nuclear reactors. We use cosmochemically a...

  10. KamLAND and Solar Antineutrino Spectrum

    CERN Document Server

    Chauhan, B C; Torrente-Lujan, E; Chauhan, Bhag C.; Pulido, Joao

    2004-01-01

    We use the recent KamLAND observations to predict the solar antineutrino spectrum at some confidence limits. We find that a scaling of the antineutrino probability with respect to the magnetic field profile --in the sense that the same probability function can be reproduced by any profile with a suitable peak field value-- can be utilised to obtain a general shape of the solar antineutrino spectrum. This scaling and the upper bound on the solar antineutrino event rate, that can be derived from the data, lead to: 1) an upper bound on the solar antineutrino flux, 2) the prediction of their energy spectrum, as the normalisation of the spectrum can be obtained from the total number of antineutrino events recorded in the experiment. We get $\\phi_{\\bar\

  11. The Daya Bay Antineutrino Detector Filling System and Liquid Mass Measurement

    CERN Document Server

    Band, H R; Draeger, E; Heeger, K M; Hinrichs, P; Lewis, C A; Mattison, H; McFarlane, M C; Webber, D M; Wenman, D; Wang, W; Wise, T; Xiao, Q

    2013-01-01

    The Daya Bay Reactor Neutrino Experiment has measured the neutrino mixing angle \\theta_{13} to world-leading precision. The experiment uses eight antineutrino detectors filled with 20-tons of gadolinium-doped liquid scintillator to detect antineutrinos emitted from the Daya Bay nuclear power plant through the inverse beta decay reaction. The precision measurement of sin^{2}2\\theta_{13} relies on the relative antineutrino interaction rates between detectors at near (400 m) and far (roughly 1.8 km) distances from the nuclear reactors. The measured interaction rate in each detector is directly proportional to the number of protons in the liquid scintillator target. A precision detector filling system was developed to simultaneously fill the three liquid zones of the antineutrino detectors and measure the relative target mass between detectors to <0.02%. This paper describes the design, operation, and performance of the system and the resulting precision measurement of the detectors' target liquid masses.

  12. Measurement of the $\\bar{p}p \\rightarrow \\bar{n}n$ Charge-Exchange Differential Cross-Section

    CERN Multimedia

    2002-01-01

    The aim of this proposal is a measurement of the differential cross-section of the $\\bar{p}$p $\\rightarrow$ $\\bar{n}$n charge-exchange reaction with a point-to-point precision of 1\\% in the forward direction, and an absolute normalization error of 3\\%. The high precision of the data should allow, inter alia, a determination of the $\\pi$NN coupling constant to better than 2\\%.\\\\ \\\\ The measurement will be done using the existing neutron and antineutron detectors built for experiment PS199 and liquid hydrogen target. In one week of running time, with a $\\bar{p}$ beam intensity of 3 $ 10 ^{5} $ $\\bar{p}$/sec, the reaction will be measured at a few $\\bar{p}$ momenta, in the range 500 to 900~MeV/c.

  13. Location of DNA damage by charge exchanging repair enzymes: effects of cooperativity on location time

    Directory of Open Access Journals (Sweden)

    Eriksen Kasper

    2005-04-01

    Full Text Available Abstract Background How DNA repair enzymes find the relatively rare sites of damage is not known in great detail. Recent experiments and molecular data suggest that individual repair enzymes do not work independently of each other, but interact with each other through charges exchanged along the DNA. A damaged site in the DNA hinders this exchange. The hypothesis is that the charge exchange quickly liberates the repair enzymes from error-free stretches of DNA. In this way, the sites of damage are located more quickly; but how much more quickly is not known, nor is it known whether the charge exchange mechanism has other observable consequences. Results Here the size of the speed-up gained from this charge exchange mechanism is calculated and the characteristic length and time scales are identified. In particular, for Escherichia coli, I estimate the speed-up is 50000/N, where N is the number of repair enzymes participating in the charge exchange mechanism. Even though N is not exactly known, a speed-up of order 10 is not entirely unreasonable. Furthermore, upon over expression of all the repair enzymes, the location time only varies as N-1/2 and not as 1/N. Conclusion The revolutionary hypothesis that DNA repair enzymes use charge exchange along DNA to locate damaged sites more efficiently is actually sound from a purely theoretical point of view. Furthermore, the predicted collective behavior of the location time is important in assessing the impact of stress-ful and radioactive environments on individual cell mutation rates.

  14. Charge exchange momentum transfer due to ion beam injection in partially ionized plasmas

    International Nuclear Information System (INIS)

    Time responses of a helium plasma to helium gas puffing without and with helium beam injection in a linear plasma device are experimentally investigated. Increase in the neutral density due to gas puffing is suppressed by ion beam injection. The experimental results show that a momentum transport from the ion beam to the puffed neutral particles occurs due to the charge exchange interaction, suggesting that charge exchange momentum transport is one of the processes responsible for the spatial redistribution of neutral atoms in partially ionized plasmas. (author)

  15. AGM2015: Antineutrino Global Map 2015.

    Science.gov (United States)

    Usman, S M; Jocher, G R; Dye, S T; McDonough, W F; Learned, J G

    2015-09-01

    Every second greater than 10(25) antineutrinos radiate to space from Earth, shining like a faint antineutrino star. Underground antineutrino detectors have revealed the rapidly decaying fission products inside nuclear reactors, verified the long-lived radioactivity inside our planet, and informed sensitive experiments for probing fundamental physics. Mapping the anisotropic antineutrino flux and energy spectrum advance geoscience by defining the amount and distribution of radioactive power within Earth while critically evaluating competing compositional models of the planet. We present the Antineutrino Global Map 2015 (AGM2015), an experimentally informed model of Earth's surface antineutrino flux over the 0 to 11 MeV energy spectrum, along with an assessment of systematic errors. The open source AGM2015 provides fundamental predictions for experiments, assists in strategic detector placement to determine neutrino mass hierarchy, and aids in identifying undeclared nuclear reactors. We use cosmochemically and seismologically informed models of the radiogenic lithosphere/mantle combined with the estimated antineutrino flux, as measured by KamLAND and Borexino, to determine the Earth's total antineutrino luminosity at . We find a dominant flux of geo-neutrinos, predict sub-equal crust and mantle contributions, with ~1% of the total flux from man-made nuclear reactors.

  16. Reactor Antineutrinos Signal all over the world

    CERN Document Server

    Ricci, B; Baldoncini, M; Esposito, J; Ludhova, L; Zavatarelli, S

    2014-01-01

    We present an updated estimate of reactor antineutrino signal all over the world, with particular attention to the sites proposed for existing and future geo-neutrino experiment. In our calculation we take into account the most updated data on Thermal Power for each nuclear plant, on reactor antineutrino spectra and on three neutrino oscillation mechanism.

  17. Antineutrino Oscillations in the Atmospheric Sector

    Energy Technology Data Exchange (ETDEWEB)

    Himmel, Alexander I.; /Caltech

    2011-05-01

    This thesis presents measurements of the oscillations of muon antineutrinos in the atmospheric sector, where world knowledge of antineutrino oscillations lags well behind the knowledge of neutrinos, as well as a search for {nu}{sub {mu}} {yields} {bar {nu}}{sub {mu}} transitions. Differences between neutrino and antineutrino oscillations could be a sign of physics beyond the Standard Model, including non-standard matter interactions or the violation of CPT symmetry. These measurements leverage the sign-selecting capabilities of the magnetized steel-scintillator MINOS detectors to analyze antineutrinos from the NuMI beam, both when it is in neutrino-mode and when it is in antineutrino-mode. Antineutrino oscillations are observed at |{Delta}{bar m}{sub atm}{sup 2}| = (3.36{sub -0.40}{sup +0.46}(stat) {+-} 0.06(syst)) x 10{sup -3} eV{sup 2} and sin{sup 2}(2{bar {theta}}{sub 23}) = 0.860{sub -0.12}{sup +0.11}(stat) {+-} 0.01(syst). The oscillation parameters measured for antineutrinos and those measured by MINOS for neutrinos differ by a large enough margin that the chance of obtaining two values as discrepant as those observed is only 2%, assuming the two measurements arise from the same underlying mechanism, with the same parameter values. No evidence is seen for neutrino-to-antineutrino transitions.

  18. Antineutrino Oscillations in the Atmospheric Sector

    Energy Technology Data Exchange (ETDEWEB)

    Himmel, Alexander I. [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2011-05-01

    This thesis presents measurements of the oscillations of muon antineutrinos in the atmospheric sector, where world knowledge of antineutrino oscillations lags well behind the knowledge of neutrinos, as well as a search for vμ → $\\bar{v}$μ transitions. Differences between neutrino and antineutrino oscillations could be a sign of physics beyond the Standard Model, including non-standard matter interactions or the violation of CPT symmetry. These measurements leverage the sign-selecting capabilities of the magnetized steel-scintillator MINOS detectors to analyze antineutrinos from the NuMI beam, both when it is in neutrino-mode and when it is in antineutrino-mode. Antineutrino oscillations are observed at |Δ$\\bar{m}$atm 2| = (3.36-0.40+0.46(stat) ± 0.06(syst)) x 10-3 eV2 and sin2(2$\\bar{θ}$23) = 0.860-0.12+0.11(stat) ± 0.01(syst). The oscillation parameters measured for antineutrinos and those measured by MINOS for neutrinos differ by a large enough margin that the chance of obtaining two values as discrepant as those observed is only 2%, assuming the two measurements arise from the same underlying mechanism, with the same parameter values. No evidence is seen for neutrino-to-antineutrino transitions.

  19. Development of the charge exchange type beam scraper system at the J-PARC

    Science.gov (United States)

    Okabe, K.; Yamamoto, K.; Kinsho, M.

    2016-03-01

    Improvement in injection beam quality at the Japan Proton Accelerator Research Complex 3-GeV rapid cycle synchrotron is to mitigate beam loss at the injection section. We developed a charge-exchange type scraper system with a thin carbon foil to collimate the beam halo in the injection beam line of the synchrotron. The key issue to realize the scraper is a reduction of the beam loss induced by the multiple-scattering effect of charge-exchange foil placed at the scraper head. In order to determine the adequate foil thickness, a charge-exchange efficiency of a carbon foil and particle-tracking simulation study of the collimated beam have been performed assuming a realistic halo at the scraper section. Using the results of this study, we chose the thickness of a 520 μg /cm2 as the scraper foils to mitigate radiation dose around the L3BT scraper section. A charge-exchange scraper system that prevents the emission of radioactive fragments of the carbon foil was build. The system was put into operation to prove its effectiveness in eliminating the beam halo. From the result of a preliminary beam experiments, we confirmed that the installed scrapers eliminate a transverse beam tail or halo. After two days of operation with beam collimation, the radiation dose level around the scraper section was a tolerable one for the hands-on maintenance.

  20. Conceptual design of the ITER upper port plug for charge exchange diagnostic

    NARCIS (Netherlands)

    Sadakov, S.; Baross, T.; Biel, W.; Borsuk, V.; Hawkes, N.; von Hellermann, M.; Gille, P.; Kiss, G.; Koning, J.; Knaup, M.; Klinkhamer, F.; Krasikov, Y.; Litnovsky, A.; Neubauer, O.; Panin, A.

    2009-01-01

    A plug for the ITER core charge exchange recombination spectroscopy (core CXRS) is located in the upper port 3. It transfers the light emitted by interaction of plasma ions with the diagnostic neutral beam (DNB). The plug consists of a main shell, a shielding cassette and a retractable tube. The tub

  1. Total cross sections for pion charge exchange on the proton

    Energy Technology Data Exchange (ETDEWEB)

    Breitschopf, J.

    2006-04-28

    This work describes the measurement of total SCX cross sections employing a new 4{pi} scintillation counter to perform transmission measurements in the incident pion energy range from about 38 to 250 MeV. A small 4{pi} detector box consisting of thin plastic scintillators has been constructed. The transmission technique, which was used, relates the number of transmitted charged pions to that of incident beam pions and this way effectively counts events with neutral products. The incoming negative pions were counted by three beam defining counters before they hit a target of very well known size and chemical composition. The target was placed in the box detector which was not sensitive to the neutral particles resulting from the SCX. The total cross section for emerging neutral particles was derived from the comparison of the numbers of the incoming and transmitted charged particles. The total SCX cross section on hydrogen was derived from the transmissions of a CH{sub 2} target, a carbon target and an empty target. For a detailed offline analysis all TDC, QDC and FADC information was recorded in an event by event mode for each triggered beam event. Various corrections had to be applied to the data, such as random correction, the detection of neutrals in the detector, Dalitz decay, pion decay and the radiative pion capture. This measurement covers, as the only experiment, the whole {delta}-resonance and the sp-interference region in one single experimental setup and improves the available data base for the SCX reaction. It is shown that the description of the SCX cross sections is improved if the s-wave amplitudes, that have been fixed essentially by elastic pion-nucleon scattering data, is reduced by (4{+-}1.5)%. The exact value depends on the SCX literature data included and on the parameters of the {delta}{sup 0} Breit-Wigner resonance describing the p{sub 33}-waves. This shows that p-wave as well as s-wave effects should be considered in studies of isospin

  2. Charged current neutrino and antineutrino interactions in hydrogen and deuterium

    International Nuclear Information System (INIS)

    In this dissertation results are presented of two different (anti-)neutrino experiments with the Big European Bubble Chamber (BEBC) filled with hydrogen and deuterium successively and exposed to the wide band (anti-)neutrino beam at the SPS at CERN. Chapter 1 contains the description of the experimental set-up and in chapter 2 results of the experiment with BEBC filled with deuterium and exposed to the antineutrino beam are presented. The multiplicity distributions of the charged hadron shower produced in (anti-)neutrino interactions with protons and neutrons are studied and compared with the results from hadron-hadron experiments. In chapter 3 a study of the exclusive reaction γp→μ-pπ+ is presented, data being obtained from an exposure of BEBC filled with hydrogen to the wide band neutrino beam. The absolute cross-section of the dominant subchannel γp→μ-Δ++(1232) averaged over an energy range of Esub(γ) = 20-200 GeV is measured to be sigma = (0.59 +- 0.06) . 10-38 cm2. This value is in good agreement with the results of other experiments. The differential cross-section dsigma/dQ2, the Δ++ decay angular distributions and the density matrix elements are determined. The value of the axial mass determined using the Schreiner-Von Hippel parametrization of the Adler model by fitting the total cross-section is Msub(A) = 0.85 +- 0.10 GeV/c2. (Auth.)

  3. Reactor monitoring and safeguards using antineutrino detectors

    CERN Document Server

    Bowden, N S

    2008-01-01

    Nuclear reactors have served as the antineutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these very weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Measurements made with antineutrino detectors could therefore offer an alternative means for verifying the power history and fissile inventory of a reactors, as part of International Atomic Energy Agency (IAEA) and other reactor safeguards regimes. Several efforts to develop this monitoring technique are underway across the globe.

  4. Daya Bay Antineutrino Detector Gas System

    CERN Document Server

    Band, H R; Chu, M-C; Heeger, K M; Kwok, M W; Shih, K; Wise, T; Xiao, Q

    2012-01-01

    The Daya Bay Antineutrino Detector gas system is designed to protect the liquid scintillator targets of the antineutrino detectors against degradation and contamination from exposure to ambient laboratory air. The gas system is also used to monitor the leak tightness of the antineutrino detector assembly. The cover gas system constantly flushes the gas volumes above the liquid scintillator with dry nitrogen to minimize oxidation of the scintillator over the five year lifetime of the experiment. This constant flush also prevents the infiltration of radon or other contaminants into these detecting liquids keeping the internal backgrounds low. Since the Daya Bay antineutrino detectors are immersed in the large water pools of the muon veto system, other gas volumes are needed to protect vital detector cables or gas lines. These volumes are also purged with dry gas. Return gas is monitored for oxygen content and humidity to provide early warning of potentially damaging leaks. The design and performance of the Daya...

  5. Web Application for Modeling Global Antineutrinos

    CERN Document Server

    Barna, Andrew

    2015-01-01

    Electron antineutrinos stream freely from rapidly decaying fission products within nuclear reactors and from long-lived radioactivity within Earth. Those with energy greater than 1.8 MeV are regularly observed by several kiloton-scale underground detectors. These observations estimate the amount of terrestrial radiogenic heating, monitor the operation of nuclear reactors, and measure the fundamental properties of neutrinos. The analysis of antineutrino observations at operating detectors or the planning of projects with new detectors requires information on the expected signal and background rates. We present a web application for modeling global antineutrino energy spectra and detection rates for any surface location. Antineutrino sources include all registered nuclear reactors as well as the crust and mantle of Earth. Visitors to the website may model the location and power of a hypothetical nuclear reactor, copy energy spectra, and analyze the significance of a selected signal relative to background.

  6. Antineutrino monitoring of spent nuclear fuel

    OpenAIRE

    Brdar, Vedran; Huber, Patrick; Kopp, Joachim

    2016-01-01

    Military and civilian applications of nuclear energy have left a significant amount of spent nuclear fuel over the past 70 years. Currently, in many countries world wide, the use of nuclear energy is on the rise. Therefore, the management of highly radioactive nuclear waste is a pressing issue. In this letter, we explore antineutrino detectors as a tool for monitoring and safeguarding nuclear waste material. We compute the flux and spectrum of antineutrinos emitted by spent nuclear fuel eleme...

  7. Neutrino Data and Neutrino-Antineutrino Transition

    CERN Document Server

    Alexeyev, E N

    2005-01-01

    A problem, whether a neutrino-antineutrino transition could be responsible for the muon neutrino deficit found in underground experiments (Super-Kamiokande, MACRO, Soudan 2) and in the accelerator long-baseline K2K experiment, is discussed in this paper. The intention of the work is not consideration of concrete models for muon neutrino-antineutrino transition but a desire to attract an attention to another possibility of understanding the nature of the measured muon neutrino deficit in neutrino experiments.

  8. Antineutrino Geophysics with Liquid Scintillator Detectors

    OpenAIRE

    Rothschild, Casey G.; Chen, Mark C.; Calaprice, Frank P.

    1997-01-01

    Detecting the antineutrinos emitted by the decay of radioactive elements in the mantle and crust could provide a direct measurement of the total abundance of uranium and thorium in the Earth. In calculating the antineutrino flux at specific sites, the local geology of the crust and the background from the world's nuclear power reactors are important considerations. Employing a global crustal map, with type and thickness data, and using recent estimates of the uranium and thorium distribution ...

  9. Antineutrino monitoring of spent nuclear fuel

    CERN Document Server

    Brdar, Vedran; Kopp, Joachim

    2016-01-01

    Military and civilian applications of nuclear energy have left a significant amount of spent nuclear fuel over the past 70 years. Currently, in many countries world wide, the use of nuclear energy is on the rise. Therefore, the management of highly radioactive nuclear waste is a pressing issue. In this letter, we explore antineutrino detectors as a tool for monitoring and safeguarding nuclear waste material. We compute the flux and spectrum of antineutrinos emitted by spent nuclear fuel elements as a function of time, and we illustrate the usefulness of antineutrino detectors in several benchmark scenarios. In particular, we demonstrate how a measurement of the antineutrino flux can help to re-verify the contents of a dry storage cask in case the monitoring chain by conventional means gets disrupted. We then comment on the usefulness of antineutrino detectors at long-term storage facilities such as Yucca mountain. Finally, we put forward antineutrino detection as a tool in locating underground "hot spots" in ...

  10. Low-energy pion double charge exchange and nucleon-nucleon correlations in nuclei

    International Nuclear Information System (INIS)

    Recent measurements of pion double-charge exchange (DCX) at energies 20 to 70 MeV are providing a new means for studying nucleon-nucleon correlations in nuclei. At these energies the nucleus is relatively transparent, allowing simpler theoretical models to be used in interpreting the data and leading to a clearer picture. Also the contribution to DCX of sequential charge-exchange scattering through the intermediate analog state is suppressed near 50 MeV and transitions through non-analog intermediate states become very important. Recent theoretical studies by several groups have shown that while transitions through the analog route involve relatively long nucleon-nucleon distances, those through non-analog intermediate states obtain nearly half their strength from nucleon pairs with less than 1 fermi separation. Thus DCX near 50 MeV is an excellent way to study short-range nucleon-nucleon correlations. 31 refs., 29 figs., 4 tabs

  11. ROSAT Observations of Solar Wind Charge Exchange with the Lunar Exosphere

    Science.gov (United States)

    Collier, Michael R.; Snowden, S. L.; Benna, M.; Carter, J. A.; Cravens, T. E.; Hills, H. Kent; Hodges, R. R.; Kuntz, K. D.; Porter, F. Scott; Read, A.; Robertson, I. P.; Sembay, S. F.; Sibeck, D. G.; Stubbs, Timothy J.; Travnicek, P.

    2012-01-01

    We analyze the ROSAT PSPC soft X-ray image of the Moon taken on 29 June 1990 by examining the radial profile of the count rate in three wedges, two wedges (one north and one south) 13-32 degrees off (19 degrees wide) the terminator towards the dark side and one wedge 38 degrees wide centered on the anti-solar direction. The radial profiles of both the north and the south wedges show substantial limb brightening that is absent in the 38 degree wide antisolar wedge. An analysis of the count rate increase associated with the limb brightening shows that its magnitude is consistent with that expected due to solar wind charge exchange (SWCX) with the tenuous lunar atmosphere. Along with Mars, Venus, and Earth, the Moon represents another solar system body at which solar wind charge exchange has been observed. This technique can be used to explore the solar wind-lunar interaction.

  12. Charge-Exchange Neutral Particle Analyzer Diagnostic of TJ-II

    Energy Technology Data Exchange (ETDEWEB)

    Fontdecaba, J. M.; Balbin, R.; Petrov, S.; TJ-II team

    2003-07-01

    A description of the Charge Exchange Neutral Particle Analyzers in operation in the heliac flexible TJ-II is reported. A description of the detectors, as well as the operation characteristics, hardware and software used in the control and analysis of the data obtained with the diagnostic is detailed. Two NPAs are in operation in TJ-II. One of them is a 5-channel analyzer and another one is an Acord-12. The 5-channel analyzer provides measurements of charge exchange neutral fluxes at five energy channels, whereas the Acord-12 can measure simultaneously two different hydrogen isotopes (H and D) at six energy channels. Their lines of sight can be varied poloidally in order to observe the different sections of the plasma. (Author) 10 refs.

  13. Charge exchange and energy loss of slowed down heavy ions channeled in silicon crystals

    International Nuclear Information System (INIS)

    This work is devoted to the study of charge exchange processes and of the energy loss of highly charged heavy ions channeled in thin silicon crystals. The two first chapters present the techniques of heavy ion channeling in a crystal, the ion-electron processes and the principle of our simulations (charge exchange and trajectory of channeled ions). The next chapters describe the two experiments performed at the GSI facility in Darmstadt, the main results of which follow: the probability per target atom of the mechanical capture (MEC) of 20 MeV/u U91+ ions as a function of the impact parameter (with the help of our simulations), the observation of the strong polarization of the target electron gas by the study of the radiative capture and the slowing down of Pb81+ ions from 13 to 8,5 MeV/u in channeling conditions for which electron capture is strongly reduced. (author)

  14. Charge exchange processes in He+/Cu scattering at low energy

    Science.gov (United States)

    Khalal-Kouache, K.; Bruckner, B.; Roth, D.; Goebl, D.; Bauer, P.

    2016-09-01

    In this paper we present results on charge exchange of He+ ions at a polycrystalline Cu surface. Monte Carlo simulations were used to calculate the trajectories of projectiles scattered by an angle Θ = 136 ° . By including Auger neutralization and charge exchange in close collisions, energy spectra of the scattered ions as well as ion fraction values were calculated for primary energies in the range 0.5-5 keV and compared to experimental results. In the simulations, the Auger neutralization rate Γ and the probabilities of resonant neutralization (PRN) and reionization (PRI) are treated as free parameters. Using well accepted values from literature for these quantities very good agreement between simulations and experimental data was achieved.

  15. Ion slowing down and charge exchange at small impact parameters selected by channeling: superdensity effects

    OpenAIRE

    L'Hoir, A.; Adoui, A.; Barrué, F.; Billebaud, A.; Bosch, F.; Bräuning-Demian, A.; Bräuning, H.; Cassimi, A.; Chevallier, M.; C. Cohen; Dauvergne, D; Demonchy, C.E.; Giot, L.; Kirsch, R.; Gumberidze, A

    2005-01-01

    In two experiments performed with 20-30 MeV/u highly charged heavy ions (Pb56+, U91+) channeled through thin silicon crystals, we observed the original features of superdensity, associated to the glancing collisions with atomic rows undergone by part of the incident projectiles. In particular the very high collision rate yields a quite specific charge exchange regime, that leads to a higher ionization probability than in random conditions. X-ray measurements show that electrons captured in ou...

  16. Nuclear charge-exchange excitations in localized covariant density functional theory

    CERN Document Server

    Liang, H Z; Nakatsukasa, T; Niu, Z M; Ring, P; Roca-Maza, X; Van Giai, N; Zhao, P W

    2014-01-01

    The recent progress in the studies of nuclear charge-exchange excitations with localized covariant density functional theory is briefly presented, by taking the fine structure of spin-dipole excitations in 16O as an example. It is shown that the constraints introduced by the Fock terms of the relativistic Hartree-Fock scheme into the particle-hole residual interactions are straightforward and robust.

  17. Achievement of the charge exchange work diminishing of an internal combustion engine in part load

    Directory of Open Access Journals (Sweden)

    Stefan POSTRZEDNIK

    2012-01-01

    Full Text Available Internal combustion engines, used for driving of different cars, occurs not only at full load, but mostly at the part load. The relative load exchange work at the full (nominal engine load is significantly low. At the part load of the IC engine its energy efficiency ηe is significantly lower than in the optimal (nominal field range of the performance parameters. One of the numerous reasons of this effect is regular growing of the relative load exchange work of the IC engine. It is directly connected with the quantitative regulation method commonly used in the IC engines. From the thermodynamic point of view - the main reason of this effect is the throttling process (causing exergy losses occurring in the inlet and outlet channels. The known proposals for solving of this problem are based on applying of the fully electronic control of the motion of inlet, outlet valves and new reference cycles.The idea presented in the paper leads to diminishing the charge exchange work of the IC engines. The problem can be solved using presented in the paper a new concept of the reference cycle (called as eco-cycle of IC engine. The work of the engine basing on the eco-cycle occurs in two 3-stroke stages; the fresh air is delivered only once for both stages, but in range of each stage a new portion of fuel is burned. Normally the charge exchange occurs once during each engine cycle realized. Elaborated proposition bases on the elimination of chosen charge exchange processes and through this the dropping of the charge exchange work can be achieved.

  18. Using Kappa Functions to Characterize Outer Heliosphere Proton Distributions in the Presence of Charge-exchange

    Science.gov (United States)

    Zirnstein, E. J.; McComas, D. J.

    2015-12-01

    Kappa functions have long been used in the analysis and modeling of suprathermal particles in various space plasmas. In situ observations of the supersonic solar wind show its distribution contains a cold ion core and power-law tail, which is well-represented by a kappa function. In situ plasma observations by Voyager, as well as observations of energetic neutral atom (ENA) spectra by the Interstellar Boundary Explorer (IBEX), showed that the compressed and heated inner heliosheath (IHS) plasma beyond the termination shock can also be represented by a kappa function. IBEX exposes the IHS plasma properties through the detection of ENAs generated by charge-exchange in the IHS. However, charge-exchange modifies the plasma as it flows through the IHS, and makes it difficult to ascertain the parent proton distribution. In this paper we investigate the evolution of proton distributions, initially represented by a kappa function, that experience losses due to charge-exchange in the IHS. In the absence of other processes, it is no longer representable by a single kappa function due to the energy-dependent, charge-exchange process. While one can still fit a kappa function to the evolving proton distribution over limited energy ranges, this yields fitting parameters (pseudo-density, pseudo-temperature, pseudo-kappa index) that depend on the energy range of the fit. We discuss the effects of fitting a kappa function to the IHS proton distribution over limited energy ranges, its dependence on the initial proton distribution properties at the termination shock, and implications for understanding the observations.

  19. Study of proton polarization in charge exchange process on optically oriented sodium atoms

    International Nuclear Information System (INIS)

    Using high-power adjustable dye lasers for electron spin orientation in a charge-exchange target enables to significantly increase the proton polarization efficiency. A device is described that permits to avoid growth of the polarized proton beam emittance in a charge-exchange process in a strong magnetic field. The devise main feature is the use of an intensive source of neutral hydrogen atoms and the presence of a helium additional charge-exchange target which actualy is a proton ''source''. The helium charge-exchange cell is placed in the same magnetic field of a solenoid where a cell with oriented sodium is placed, a polarized electron being captured by a proton in the latter cell. In this case the beam at the solenoid inlet and outlet is in a neutral state; emittance growth related to the effect of end magnetic fields is not observed. The device after all prouduces polarized protons, their polarization degree is measured and the effect of various factors on polarization degree is studied. The description of the laser source and laser system is given. Measurement results have shown the beam intensity of neutral 7 keV atoms which passed through a polarizer to be 2 mA. The proton current doesn't depend. On the beeld fin the region of chrge exchange for the 8 kGs magnetic field. The degree of sodium polarization was 80% and polarized proton current approximately 70 μA at a temperature of the polarized sodium cell corresponding to the density of sodium vapar approximately 3x1013 at/cm2

  20. Solar wind charge exchange X-ray emission from Mars Model and data comparison

    OpenAIRE

    Koutroumpa, Dimitra; Modolo, Ronan; Chanteur, Gerard; Chaufray, Jean-Yves; Kharchenko, Vasili; Lallement, Rosine

    2012-01-01

    Aims. We study the soft X-ray emission induced by charge exchange (CX) collisions between solar-wind, highly charged ions and neutral atoms of the Martian exosphere. Methods. A 3D multi species hybrid simulation model with improved spatial resolution (130 km) is used to describe the interaction between the solar wind and the Martian neutrals. We calculated velocity and density distributions of the solar wind plasma in the Martian environment with realistic planetary ions description, using sp...

  1. N(+)-N long-range interaction energies and resonance charge exchange

    Science.gov (United States)

    Stallcop, J. R.; Partridge, H.

    1985-01-01

    The aerothermodynamic studies of proposed space missions require atmospheric charge-transfer data. N2(+) eigenstate energies are calculated with use of the complete-active-space self-consistent-field method with an extended Gaussian basis set. The N(+)-N charge-exchange cross section, determined from these energies, agrees with merged-beam measurements. This contradicts the previous theoretical conclusion. A simple physical description of the long-range interaction is presented and should expedite future charge-transfer studies.

  2. Charge-exchange excitations with finite range interactions including tensor terms

    CERN Document Server

    De Donno, V; Anguiano, M; Lallena, A M

    2014-01-01

    We study charge-exchange excitations in doubly magic-nuclei by using a self-consistent Hartree-Fock plus Random Phase Approximation model. We use four Gogny-like finite-range interactions, two of them containing tensor forces. We investigate the effects of the various parts of the tensor forces in the two computational steps of our model, and we find that their presence is not negligible and improves the agreement with the experimental data.

  3. Nuclear charge-exchange excitations in localized covariant density functional theory

    International Nuclear Information System (INIS)

    The recent progress in the studies of nuclear charge-exchange excitations with localized covariant density functional theory is briefly presented, by taking the fine structure of spin-dipole excitations in 16O as an example. It is shown that the constraints introduced by the Fock terms of the relativistic Hartree-Fock scheme into the particle-hole residual interactions are straightforward and robust. (authors)

  4. Charge-exchange scattering in K- p interactions below 300 MeV/c

    International Nuclear Information System (INIS)

    Cross sections for K-p charge exchange, based on new data equal in statistics to the sum of those of all previous determinations below 300 MeV/c, are presented. The results confirm an earlier observation by this collaboration that the previous measurements of these cross sections at low momentum were significantly underestimated. Evidence for the presence of P wave scattering is presented. (author)

  5. Coherent control of charge exchange in strong-field dissociation of LiF

    Science.gov (United States)

    Armstrong, Greg; Esry, Brett

    2016-05-01

    The alkali-metal-halides family of molecules are useful prototypes in the study of laser-assisted charge exchange. Typically these molecules possess a field-free crossing between the ionic and covalent diabatic Born-Oppenheimer potential curves, leading to Li+ + F- and Li + F in LiF. These channels are energetically well-separated from higher-lying potentials, and may be easily distinguished experimentally. Moreover, charge exchange involves non-adiabatic transitions between the ionic and covalent channels, thereby allowing the investigation of physics beyond the Born-Oppenheimer approximation. The focus of this work is to control the preference between ionic and covalent dissociative products. We solve the time-dependent Schrödinger equation for the nuclear motion in full dimensionality, and investigate a pump-probe scheme for charge-exchange control. The degree of control is investigated by calculating the kinetic-energy release spectrum as a function of pump-probe delay for the ionic and covalent fragments. This work is supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy.

  6. Modeling the Hydrogen-Proton Charge-Exchange Process in Global Heliospheric Simulations

    Science.gov (United States)

    DeStefano, A.; Heerikhuisen, J.

    2015-12-01

    The environment surrounding our Solar System has a vast and dynamic structure. As the Sun rounds the Milky Way galaxy, interstellar dust and gas interact with the Sun's outflow of solar wind. A bubble of hot plasma forms around the Sun due to this interaction, called the heliosphere. In order to understand the structure of the heliosphere, observations and simulations must work in tandem. Within the past decade or so, 3D models of the heliosphere have been developed exhibiting non- symmmetric as well as predicting structures such as the hydrogen wall and the IBEX ribbon. In this poster we explore new ways to compute charge-exchange source terms. The charge-exchange process is the coupling mechanism between the MHD and kinetic theories. The understanding of this process is crucial in order to make valuable predictions. Energy dependant cross section terms will aid in settling non-linear affects coupling the intestellar and solar particles. Through these new ways of computing source terms, resolving fine structures in the plasma in the heliopause may be possible. In addition, other non-trivial situations, such as charge-exchange mediated shocks, may be addressed.

  7. Wavelength calibration of the charge exchange recombination spectroscopy system on the DIII-D tokamak

    International Nuclear Information System (INIS)

    A wavelength calibration of all the detectors on the charge exchange recombination spectroscopy (CER) system is performed after every plasma discharge on the DIII-D tokamak. This is done to insure that the rest wavelength position of the C VI 5290.5 angstrom charge exchange line on the detector is accurately known so that the Doppler shift of the spectral line emitted during the discharge can be used for measurements of plasma rotation. In addition, this calibration provides a check on the spectral dispersion needed to determine the ion temperature. The reference spectra for the calibration are Ne I lines created by neon capillary discharge lamps contained within specially designed, diffuse reflectors. The Ne I lines at 3520.4720 angstrom, 5274.0393 angstrom, 5280.0853 angstrom, 5298.1891 angstrom, and 5304.7580 angstrom are used in this work. The location of these lines on the linear detectors can be determined to an accuracy of 0.1 pixel, which corresponds to a plasma rotation accuracy of 1.2 km/s and 0.7 km/s for the central and edge rotation measurements, respectively. Use of oppositely directed views of the plasma at the same major radius have been used to verify that the nominal 5290.5 angstrom wavelength of the C VI (n = 8 → 7) multiplet is the correct wavelength for the line emitted owing to charge exchange excitation

  8. Unresolved puzzles in the x-ray emission produced by charge exchange measured on electron beam ion traps

    International Nuclear Information System (INIS)

    Charge exchange recombination, the transfer of one or more electrons from an atomic or molecular system to a positive ion, is a common phenomenon affecting laboratory and astrophysical plasmas. Controlled studies of this process in electron beam ion traps during the past one and a half decades have produced multiple observations that are difficult to explain with available spectral models. Some of the most recent observations are so puzzling that they bring in doubt the existence of a coherent predictive capability for line formation by charge exchange, making investigations of charge exchange a fertile ground for continued measurements and theoretical development.

  9. Unresolved puzzles in the x-ray emission produced by charge exchange measured on electron beam ion traps

    Energy Technology Data Exchange (ETDEWEB)

    Beiersdorfer, P.; Brown, G. V.; Clementson, J. [Physics Division, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, California 94550 (United States); Kilbourne, C. A.; Kelley, R. L.; Leutenegger, M. A.; Porter, F. S. [NASA Goddard Space Flight Center, Greenbelt, Maryland 20771 (United States); Schweikhard, L. [Institute of Physics, Ernst-Moritz-Arndt University, D-17487 Greifswald (Germany)

    2013-04-19

    Charge exchange recombination, the transfer of one or more electrons from an atomic or molecular system to a positive ion, is a common phenomenon affecting laboratory and astrophysical plasmas. Controlled studies of this process in electron beam ion traps during the past one and a half decades have produced multiple observations that are difficult to explain with available spectral models. Some of the most recent observations are so puzzling that they bring in doubt the existence of a coherent predictive capability for line formation by charge exchange, making investigations of charge exchange a fertile ground for continued measurements and theoretical development.

  10. Folding model study of the charge-exchange scattering to the isobaric analog state and implication for the nuclear symmetry energy

    Energy Technology Data Exchange (ETDEWEB)

    Khoa, Dao T.; Thang, Dang Ngoc [VINATOM, Institute for Nuclear Science and Technique, Hanoi (Viet Nam); Loc, Bui Minh [VINATOM, Institute for Nuclear Science and Technique, Hanoi (Viet Nam); University of Pedagogy, Ho Chi Minh City (Viet Nam)

    2014-02-15

    The Fermi transition (ΔL = ΔS = 0 and ΔT = 1) between the nuclear isobaric analog states (IAS), induced by the charge-exchange (p, n) or ({sup 3}He, t) reaction, can be considered as ''elastic'' scattering of proton or {sup 3}He by the isovector term of the optical potential (OP) that flips the projectile isospin. The accurately measured (p, n) or ({sup 3}He, t) scattering cross section to the IAS can be used, therefore, to probe the isospin dependence of the proton or {sup 3}He optical potential. Within the folding model, the isovector part of the OP is determined exclusively by the neutron-proton difference in the nuclear densities and the isospin dependence of the effective nucleon-nucleon (NN) interaction. Because the isovector coupling explicitly links the isovector part of the proton or {sup 3}He optical potential to the cross section of the charge-exchange (p, n) or ({sup 3}He, t) scattering to the IAS, the isospin dependence of the effective (in-medium) NN interaction can be well tested in the folding model analysis of these charge-exchange reactions. On the other hand, the same isospin- and density-dependent NN interaction can also be used in a Hartree-Fock calculation of asymmetric nuclear matter, to estimate the nuclear matter energy and its asymmetry part (the nuclear symmetry energy). As a result, the fine-tuning of the isospin dependence of the effective NN interaction against the measured (p, n) or ({sup 3}He, t) cross sections should allow us to make some realistic prediction of the nuclear symmetry energy and its density dependence. (orig.)

  11. Observed Limits on Charge Exchange Contributions to the Diffuse X-Ray Background

    Science.gov (United States)

    Crowder, S. G.; Barger, K. A.; Brandl, D. E.; Eckart, M. E.; Galeazzi, M.; Kelley, R. L.; Kilbourne, C. A.; McCammon, D.; Pfendner, C. G.; Porter, F. S.; Rocks, L.; Szymkowiak, A. E.; Teplin, I. M.

    2012-01-01

    We present a high-resolution spectrum of the diffuse X-ray background from 0.1 to 1 keV for an approximately 1 sr region of the sky centered at l = 90 degrees b = +60 degrees using a 36 pixel array of microcalorimeters flown on a sounding rocket. With an energy resolution of 11 eV FWHM below 1 keV, the spectrum s observed line ratios help separate charge exchange contributions originating within the heliosphere from thermal emission of hot gas in the interstellar medium. The X-ray sensitivity below 1 keV was reduced by about a factor of four from contamination that occurred early in the flight, limiting the significance of the results. The observed centroid of helium-like O VII is 568 (sup +2 (sub -3) eV at 90% confidence. Since the centroid expected for thermal emission is 568.4 eV and for charge exchange is 564.2 eV, thermal emission appears to dominate for this line complex. The dominance of thermal emission is consistent with much of the high-latitude O VII emission originating in 2-3 x 10(exp 6) K gas in the Galactic halo. On the other hand, the observed ratio of C VI Lygamma to Lyalpha is 0.3 plus or minus 0.2. The expected ratios are 0.04 for thermal emission and 0.24 for charge exchange, indicating that charge exchange must contribute strongly to this line and therefore potentially to the rest of the ROSAT R12 band usually associated with 10(sup 6) K emission from the Local Hot Bubble. The limited statistics of this experiment and systematic uncertainties due to the contamination require only greater than 32% thermal emission for O VII and greater than 20% from charge exchange for C VI at the 90% confidence level. An experimental gold coating on the silicon substrate of the array greatly reduced extraneous signals induced on nearby pixels from cosmic rays passing through the substrate, reducing the triggered event rate by a factor of 15 from a previous flight of the instrument.

  12. Workshop applied antineutrino physics 2007

    International Nuclear Information System (INIS)

    The 'Applied Antineutrino Physics 2007' workshop is the fourth international meeting devoted to the opening of the neutrino physics to more applied fields, such as geophysics and geochemistry, nuclear industry, as well as the nonproliferation. This meeting highlights the world efforts already engaged to exploit the single characteristics of the neutrinos for the control of the production of plutonium in the civil nuclear power reactor. The potential industrial application of the measurement of the thermal power of the nuclear plants by the neutrinos is also approached. earth neutrinos were for the first time highlighted in 2002 by the KamLAND experiment. Several international efforts are currently underway to use earth neutrinos to reveal the interior of the Earth. This meeting is an opportunity to adapt the efforts of detection to the real needs of geophysicists and geochemists (sources of radiogenic heat, potassium in the court, feathers.) Finally more futuristic topics such as the detection of nuclear explosions, of low powers, are also discussed. This document gathers only the slides of the presentations

  13. Workshop applied antineutrino physics 2007

    Energy Technology Data Exchange (ETDEWEB)

    Akiri, T.; Andrieu, B.; Anjos, J.; Argyriades, J.; Barouch, G.; Bernstein, A.; Bersillon, O.; Besida, O.; Bowden, N.; Cabrera, A.; Calmet, D.; Collar, J.; Cribier, M.; Kerret, H. de; Meijer, R. de; Dudziak, F.; Enomoto, S.; Fallot, M.; Fioni, G.; Fiorentini, G.; Gale, Ph.; Georgadze, A.; Giot, L.; Gonin, M.; Guillon, B.; Henson, C.; Jonkmans, G.; Kanamaru, S.; Kawasaki, T.; Kornoukhov, V.; Lasserre, Th.; Learned, J.G.; Lefebvre, J.; Letourneau, A.; Lhillier, D.; Lindner, M.; Lund, J.; Mantovani, F.; Mcdonough, B.; Mention, G.; Monteith, A.; Motta, D.; Mueller, Th.; Oberauer, L.; Obolensky, M.; Odrzywolek, A.; Petcov, S.; Porta, A.; Queval, R.; Reinhold, B.; Reyna, D.; Ridikas, D.; Sadler, L.; Schoenert, St.; Sida, J.L.; Sinev, V.; Suekane, F.; Suvorov, Y.; Svoboda, R.; Tang, A.; Tolich, N.; Tolich, K.; Vanka, S.; Vignaud, D.; Volpe, Ch.; Wong, H

    2007-07-01

    The 'Applied Antineutrino Physics 2007' workshop is the fourth international meeting devoted to the opening of the neutrino physics to more applied fields, such as geophysics and geochemistry, nuclear industry, as well as the nonproliferation. This meeting highlights the world efforts already engaged to exploit the single characteristics of the neutrinos for the control of the production of plutonium in the civil nuclear power reactor. The potential industrial application of the measurement of the thermal power of the nuclear plants by the neutrinos is also approached. earth neutrinos were for the first time highlighted in 2002 by the KamLAND experiment. Several international efforts are currently underway to use earth neutrinos to reveal the interior of the Earth. This meeting is an opportunity to adapt the efforts of detection to the real needs of geophysicists and geochemists (sources of radiogenic heat, potassium in the court, feathers.) Finally more futuristic topics such as the detection of nuclear explosions, of low powers, are also discussed. This document gathers only the slides of the presentations.

  14. Charge exchange and knockout reactions induced by Sn isotopes at relativistic energies

    OpenAIRE

    Vargas Cruz, Jossitt Williams

    2014-01-01

    El objetivo de este trabajo de tesis doctoral es estudiar excitaciones nucleares y subnucleares utilizando reacciones periféricas de núcleos pesados inducidas por proyectiles relativistas de núcleos estables e inestables. En particular se propone estudiar estas excitaciones usando reacciones de intercambio de carga isóbaras y de arranque de nucleones. Las reacciones de intercambio de carga corresponden a excitaciones espínisoesp ín que pueden proporcionar informaci´on sobre ...

  15. Charge exchange cross sections for the reaction Xe+8 + Xe+8 → Xe+9 + Xe+7

    International Nuclear Information System (INIS)

    The charge changing cross sections for self collisions of Xe+8 ions with 0 to 150 keV relative translational kinetic energy are estimated on the basis of the Fano-Lichten electron promotion model. It is concluded that for Xe+8 + Xe+8, charge changing collisions occur only infrequently compared to excitation and with cross sections much smaller than 10-18 cm2

  16. Possible Charge-Exchange X-Ray Emission in the Cygnus Loop Detected with Suzaku

    Science.gov (United States)

    Katsuda, Satoru; Tsunemi, Hiroshi; Mori, Koji; Uchida, Hiroyuki; Kosugi, Hiroko; Kimura, Masashi; Nakajima, Hiroshi; Takakura, Satoru; Petre, Robert; Hewitt. John W.; Yamaguchi, Hiroya

    2011-01-01

    X-ray spectroscopic measurements of the Cygnus Loop supernova remnant indicate that metal abundances throughout most of the remnant s rim are depleted to approx.0.2 times the solar value. However, recent X-ray studies have revealed in some narrow regions along the outermost rim anomalously "enhanced" abundances (up to approx. 1 solar). The reason for these anomalous abundances is not understood. Here, we examine X-ray spectra in annular sectors covering nearly the entire rim of the Cygnus Loop using Suzaku (21 pointings) and XMM-Newton (1 pointing). We find that spectra in the "enhanced" abundance regions commonly show a strong emission feature at approx.0.7 keV. This feature is likely a complex of He-like O K(gamma + delta + epsilon), although other possibilities cannot be fully excluded. The intensity of this emission relative to He-like O K(alpha) appears to be too high to be explained as thermal emission. This fact, as well as the spatial concentration of the anomalous abundances in the outermost rim, leads us to propose an origin from charge-exchange processes between neutrals and H-like O. We show that the presence of charge-exchange emission could lead to the inference of apparently "enhanced" metal abundances using pure thermal emission models. Accounting for charge-exchange emission, the actual abundances could be uniformly low throughout the rim. The overall abundance depletion remains an open question. Subject headings: ISM: abundances ISM: individual objects (Cygnus Loop) ISM: supernova remnants X-rays: ISM atomic processes

  17. Detection of Antineutrinos for Non-Proliferation

    CERN Document Server

    Nieto, M M; Teeter, C M; Wilson, W B; Stanbro, W D; Nieto, Michael Martin; Teeter, Corinne M.; Wilson, William B.; Stanbro, William D.

    2003-01-01

    We discuss the feasibility of using the detection of electron antineutrinos produced in fission to monitor the time dependence of the Plutonium content of nuclear power reactors and large (> 1 MWatt) research reactors. If practical such a scheme would allow world-wide, automated monitoring of reactors and, thereby, the detection of proliferation attempts. Although this idea shows some promise, we find that a practical scheme is difficult to envision. We also consider using fission antineutrino spectra to determine and attribute the fuel in an unexploded nuclear device. We find it would not be possible to determine the isotopic content of such a device in this manner. Finally, we examine the possibility of antineutrino detection of an unannounced low-yield (~ 1kton) nuclear explosion. We argue this can be ruled out completely.

  18. Antineutrino induced antikaon production off the nucleon

    CERN Document Server

    Alam, M Rafi; Athar, M Sajjad; Vacas, M J Vicente

    2011-01-01

    The charged current antikaon production off nucleons induced by antineutrinos is studied at low and intermediate energies. We extend here our previous calculation on kaon production induced by neutrinos. We have developed a microscopic model that starts from the SU(3) chiral Lagrangians and includes background terms and the resonant mechanisms associated to the lowest lying resonance in the channel, namely, the Sigma*(1385). Our results could be of interest for the background estimation of various neutrino oscillation experiments like MiniBooNE and SuperK. They can also be helpful for the planned antineutrino experiments like MINERvA, NOvA and T2K phase II and for beta-beam experiments with antineutrino energies around 1 GeV.

  19. Applied Anti-neutrino Physics 2013

    CERN Document Server

    2013-01-01

    This year, the 9th annual Applied Antineutrino Physics Workshop will be hosted by Sejong University, at the COEX conference center in Seoul South Korea. The workshop will be held on November 1(Friday) - 2(Saturday), 2013. Conveniently for many travelers, it takes place directly after and at the same venue as the 2013 IEEE Nuclear Science Symposium (http://www.nss-mic.org/2013/NSSMain.asp) Applied Antineutrino Physics describes an ensemble of experimental and theoretical efforts which aim to use the antineutrino signal from nuclear reactors, and from the Earth itself, in order to address practical problems in nonproliferation and geology respectively. Since the 2004 inception of these workshops, groups worldwide have made considerable advances in defining and expanding the field, garnering interest from the International Atomic Energy Agency (IAEA), which administers the worlds most important nonproliferation regime, and from the geology/geophysics community. This meeting will focus on the current activi...

  20. Charge-exchange-driven X-ray emission from highly ionized plasma jets

    Energy Technology Data Exchange (ETDEWEB)

    Rosmej, F.B. [Universite de Provence et CNRS UMR 6633, Centre de St Jerome, 13 - Marseille (France); Lisitsa, V.S. [Russian Research Center Kurchatov, Moscow (Russian Federation); Schott, R.; Dalimier, E. [Paris-6 Univ., 75 - Paris (France); Schott, R.; Dalimier, E. [Ecole Polytechnique, LULI, 91 - Palaiseau (France); Riley, D.; Delserieys, A. [Queens Univ., Belfast (United Kingdom); Renner, O.; Krousky, E. [Institute of Physics, Prague (Czech Republic)

    2006-12-15

    The interaction of highly ionized laser-produced plasma jets with gases has been studied with X-ray microscopic methods. Simultaneous high spectral and 2-dimensional spatial resolution provided a detailed topological structure of the counter-propagating plasma and discovered a gas pressure-dependent X-ray emission structure inside the jets of H-like and He-like aluminum ions. At larger distances from the target, anomalous high (3 orders of magnitude) intensities of Li-like intercombination transitions from double excited states have been identified. Charge-exchange-driven cascading in autoionizing states is proposed to explain the experimental findings. (authors)

  1. Spatially resolved charge exchange flux calculations on the Toroidal Pumped Limiter of Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Marandet, Y., E-mail: yannick.marandet@piim.up.univ-mrs.f [PIIM, CNRS/Universite de Provence, Marseille (France); Tsitrone, E. [Association Euratom-CEA, CEA/DSM/DRFC CEA Cadarache (France); Boerner, P.; Reiter, D. [IEF-4 Plasmaphysik, Forschungszentrum Juelich GmbH, Association EURATOM-FZJ, TEC (Germany); Beaute, A.; Delchambre, E. [Association Euratom-CEA, CEA/DSM/DRFC CEA Cadarache (France); Escarguel, A. [PIIM, CNRS/Universite de Provence, Marseille (France); Brezinsek, S. [IEF-4 Plasmaphysik, Forschungszentrum Juelich GmbH, Association EURATOM-FZJ, TEC (Germany); Genesio, P. [PIIM, CNRS/Universite de Provence, Marseille (France); Gunn, J.; Monier-Garbet, P.; Mitteau, R.; Pegourie, B. [Association Euratom-CEA, CEA/DSM/DRFC CEA Cadarache (France)

    2009-06-15

    A spatially resolved calculation of the charge exchange particle and energy fluxes on the Toroidal Pumped Limiter (TPL) of Tore Supra is presented, as a first step towards a better understanding and modelling of carbon erosion, migration, as well as deuterium codeposition and bulk diffusion of deuterium in Tore Supra. The results are obtained with the EIRENE code run in a 3D geometry. Physical and chemical erosion maps on the TPL are calculated, and the contribution of neutrals to erosion, especially in the self-shadowed area, is calculated.

  2. High resolution probe of coherence in low-energy charge exchange collisions with oriented targets

    OpenAIRE

    Leredde, A.; Fléchard, X.; Cassimi, A.; Hennecart, D.; Pons, B.

    2013-01-01

    The trapping lasers of a magneto-optical trap (MOT) are used to bring Rb atoms into well defined oriented states. Coupled to recoil-ion momentum spectroscopy (RIMS), this yields a unique MOTRIMS setup which is able to probe scattering dynamics, including their coherence features, with unprecedented resolution. This technique is applied to the low-energy charge exchange processes Na$^+$+Rb($5p_{\\pm 1}$) $\\rightarrow$ Na($3p,4s$)+Rb$^+$. The measurements reveal detailed features of the collisio...

  3. High resolution probe of coherence in low-energy charge exchange collisions with oriented targets

    CERN Document Server

    Leredde, A; Cassimi, A; Hennecart, D; Pons, B

    2013-01-01

    The trapping lasers of a magneto-optical trap (MOT) are used to bring Rb atoms into well defined oriented states. Coupled to recoil-ion momentum spectroscopy (RIMS), this yields a unique MOTRIMS setup which is able to probe scattering dynamics, including their coherence features, with unprecedented resolution. This technique is applied to the low-energy charge exchange processes Na$^+$+Rb($5p_{\\pm 1}$) $\\rightarrow$ Na($3p,4s$)+Rb$^+$. The measurements reveal detailed features of the collisional interaction which are employed to improve the theoretical description. All of this enables to gauge the reliability of intuitive pictures predicting the most likely capture transitions.

  4. A photodiode-based neutral particle bolometer for characterizing charge-exchanged fast-ion behavior

    Energy Technology Data Exchange (ETDEWEB)

    Clary, R.; Smirnov, A.; Dettrick, S.; Knapp, K.; Korepanov, S.; Ruskov, E. [Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688 (United States); Heidbrink, W. W.; Zhu, Y. [University of California-Irvine, Irvine, California 92697 (United States)

    2012-10-15

    A neutral particle bolometer (NPB) has been designed and implemented on Tri Alpha Energy's C-2 device in order to spatially and temporally resolve the charge-exchange losses of fast-ion populations originating from neutral beam injection into field-reversed configuration plasmas. This instrument employs a silicon photodiode as the detection device with an integrated tungsten filter coating to reduce sensitivity to light radiation. Here we discuss the technical aspects and calibration of the NPB, and report typical NPB measurement results of wall recycling effects on fast-ion losses.

  5. A photodiode-based neutral particle bolometer for characterizing charge-exchanged fast-ion behavior.

    Science.gov (United States)

    Clary, R; Smirnov, A; Dettrick, S; Knapp, K; Korepanov, S; Ruskov, E; Heidbrink, W W; Zhu, Y

    2012-10-01

    A neutral particle bolometer (NPB) has been designed and implemented on Tri Alpha Energy's C-2 device in order to spatially and temporally resolve the charge-exchange losses of fast-ion populations originating from neutral beam injection into field-reversed configuration plasmas. This instrument employs a silicon photodiode as the detection device with an integrated tungsten filter coating to reduce sensitivity to light radiation. Here we discuss the technical aspects and calibration of the NPB, and report typical NPB measurement results of wall recycling effects on fast-ion losses. PMID:23126887

  6. Simulations of Ion Velocity Distribution Functions Taken into Account Both Elastic and Charge Exchange Collisions

    CERN Document Server

    Wang, Huihui; Kaganovich, Igor D; Mustafaev, Alexander S

    2016-01-01

    Based on accurate representation of the He+-He differential angular scattering cross sections consisting of both elastic and charge exchange collisions, we performed detailed numerical simulations of the ion velocity distribution functions (IVDF) by Monte Carlo collision method (MCC). The results of simulations are validated by comparison with the experimental data of the mobility and the transverse diffusion. The IVDF simulation study shows that due to significant effect of scattering in elastic collisions IVDF cannot be separated into product of two independent IVDFs in the transverse and parallel to the electric field directions.

  7. The first test experiment of H- charge-exchange injection in the KEK booster

    International Nuclear Information System (INIS)

    The H- charge-exchange injection method was applied to the 500 MeV booster of the 12 GeV proton synchrotron at KEK, as an alternative to the multi-turn injection method using direct injection of protons. The first test experiment of such injection was carried out during three weeks beginning in late September 1983. Experimental results showed that, in spite of the low injection energy used for our booster, such an injection method is promising for increasing the beam intensity of the booster. And also, some further improvements are proposed. (author)

  8. The observation of charge exchange of pions captured in several nuclei

    Science.gov (United States)

    Bassalleck, B.; Corriveau, F.; Hasinoff, M. D.; Marks, T.; Measday, D. F.; Poutissou, J.-M.; Salomon, M.

    1981-06-01

    We have measured for the first time the branching ratios of the charge exchange of stopped negative pions in targets of 6Li, Al, Ti, Cu, Nb and Pb. These branching ratios are of the order of 10 -6, about an order of magnitude smaller than the upper limit previously established. Using the branching ratio for radiative pion capture in 6Li to the ground state of 6He we obtain the Panofsky ratio in 6Li, P6 = (8.7 ± 2.3) × 10 -4.

  9. Low-energy Antineutrinos from the Sun

    CERN Document Server

    Pastor, S; Valle, José W F; Pastor, Sergio; Semikoz, Viktor B.; Valle, Jose W.F.

    1998-01-01

    We consider the sensitivity of future neutrino experiments in the low energy region, such as BOREXINO or HELLAZ, to a solar electron antineutrino signal. We show that, if neutrino conversions within the Sun result in partial polarization of initial solar neutrino fluxes, then a new opportunity arises to observe the electron antineutrinos and thus to probe the Majorana nature of the neutrinos. This is achieved by comparing the slopes of the energy dependence of the differential neutrino electron scattering cross section for different neutrino conversion scenarios. We also show how the \

  10. Observed Limits on Charge Exchange Contributions to the Diffuse X-ray Background

    CERN Document Server

    Crowder, S G; Brandl, D E; Eckart, M E; Galeazzi, M; Kelley, R L; Kilbourne, C A; McCammon, D; Pfendner, C G; Porter, F S; Rocks, L; Szymkowiak, A E; Teplin, I M

    2012-01-01

    We present a high resolution spectrum of the diffuse X-ray background from 0.1 to 1 keV for a ~1 region of the sky centered at l=90, b=+60 using a 36-pixel array of microcalorimeters flown on a sounding rocket. With an energy resolution of 11 eV FWHM below 1 keV, the spectrum's observed line ratios help separate charge exchange contributions originating within the heliosphere from thermal emission of hot gas in the interstellar medium. The X-ray sensitivity below 1 keV was reduced by about a factor of four from contamination that occurred early in the flight, limiting the significance of the results. The observed centroid of helium-like O VII is 568+2-3 eV at 90% confidence. Since the centroid expected for thermal emission is 568.4 eV while for charge exchange is 564.2 eV, thermal emission appears to dominate for this line complex, consistent with much of the high-latitude O VII emission originating in 2-3 x 10^6 K gas in the Galactic halo. On the other hand, the observed ratio of C VI Ly gamma to Ly alpha is...

  11. Observations of solar wind ion charge exchange in the Comet Halley coma

    Science.gov (United States)

    Fuselier, S. A.; Shelley, E. G.; Goldstein, B. E.; Goldstein, R.; Neugebauer, M.; Ip, W.-H.; Balsiger, H.; Reme, H.

    1991-01-01

    Giotto Ion Mass Spectrometer/High Energy Range Spectrometer (IMS/HERS) observations of solar wind ions show charge exchange effects and solar wind compositional changes in the coma of Comet Halley. As the comet was approached, the He(2+) to proton density ratio increased from 2.5 percent in the solar wind to about 4 percent about 1 hr before closest approach after which time it decreased to about 1 percent. Abrupt increases in this ratio from 2.5 to 4.5 percent were also observed in the beginning and near the end of the so-called Mystery Region. These abrupt increases in the density ratio were well correlated with enhanced fluxes of keV electrons as measured by the Giotto plasma electron spectrometer. The general increase and then decrease of the He(2+) to proton density ratio is quantitatively consistent with a combination of the addition of protons of Cometary origin to the plasma and loss of plasma through charge exchange of protons and He(2+).

  12. First measurement of the edge charge exchange recombination spectroscopy on EAST tokamak

    Science.gov (United States)

    Li, Y. Y.; Yin, X. H.; Fu, J.; Jiang, D.; Feng, S. Y.; Lyu, B.; Shi, Y. J.; Yi, Y.; Zhou, X. J.; Hu, C. D.; Ye, M. Y.; Wan, B. N.

    2016-11-01

    An edge toroidal charge exchange recombination spectroscopy (eCXRS) diagnostic, based on a heating neutral beam injection (NBI), has been deployed recently on the Experimental Advanced Superconducting Tokamak (EAST). The eCXRS, which aims to measure the plasma ion temperature and toroidal rotation velocity in the edge region simultaneously, is a complement to the exiting core CXRS (cCXRS). Two rows with 32 fiber channels each cover a radial range from ˜2.15 m to ˜2.32 m with a high spatial resolution of ˜5-7 mm. Charge exchange emission of Carbon VI CVI at 529.059 nm induced by the NBI is routinely observed, but can be tuned to any interested wavelength in the spectral range from 400 to 700 nm. Double-slit fiber bundles increase the number of channels, the fibers viewing the same radial position are binned on the CCD detector to improve the signal-to-noise ratio, enabling shorter exposure time down to 5 ms. One channel is connected to a neon lamp, which provides the real-time wavelength calibration on a shot-to-shot basis. In this paper, an overview of the eCXRS diagnostic on EAST is presented and the first results from the 2015 experimental campaign will be shown. Good agreements in ion temperature and toroidal rotation are obtained between the eCXRS and cCXRS systems.

  13. Ne X X-ray Emission due to Charge Exchange in M82

    CERN Document Server

    Cumbee, R S; Lyons, D; Schultz, D R; Stancil, P C; Wang, J G; Ali, R

    2016-01-01

    Recent X-ray observations of star-forming galaxies such as M82 have shown the Ly beta/Ly alpha line ratio of Ne X to be in excess of predictions for thermal electron impact excitation. Here we demonstrate that the observed line ratio may be due to charge exchange and can be used to constrain the ion kinetic energy to be <500 eV/u. This is accomplished by computing spectra and line ratios via a range of theoretical methods and comparing these to experiments with He over astrophysically relevant collision energies. The charge exchange emission spectra calculations were performed for Ne[10+] +H and Ne[10+] +He using widely applied approaches including the atomic orbital close coupling, classical trajectory Monte Carlo, and multichannel Landau- Zener (MCLZ) methods. A comparison of the results from these methods indicates that for the considered energy range and neutrals (H, He) the so-called "low-energy l-distribution" MCLZ method provides the most likely reliable predictions.

  14. High spatial and temporal resolution charge exchange recombination spectroscopy on the HL-2A tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Y. L.; Yu, D. L., E-mail: yudl@swip.ac.cn; Liu, L.; Cao, J. Y.; Sun, A. P.; Ma, Q.; Chen, W. J.; Liu, Yi; Yan, L. W.; Yang, Q. W.; Duan, X. R.; Liu, Yong [Southwestern Institute of Physics, Chengdu 610041 (China); Ida, K. [National Institute for Fusion Science, Toki 509-5292 (Japan); Hellermann, M. von [ITER Diagnostic Team, IO, Route de Vinon sur Verdon, 13115 St Paul lez Durance (France); FOM-Institute for Plasma physics “Rijnhuizen,” Association EURATOM, Trilateral Euregio Cluster, 3430 BE Nieuwegein (Netherlands)

    2014-10-01

    A 32/64-channel charge exchange recombination spectroscopy (CXRS) diagnostic system is developed on the HL-2A tokamak (R = 1.65 m, a = 0.4 m), monitoring plasma ion temperature and toroidal rotation velocity simultaneously. A high throughput spectrometer (F/2.8) and a pitch-controlled fiber bundle enable the temporal resolution of the system up to 400 Hz. The observation geometry and an optimized optic system enable the highest radial resolution up to ~1 cm at the plasma edge. The CXRS system monitors the carbon line emission (C VI, n = 8–7, 529.06 nm) whose Doppler broadening and Doppler shift provide ion temperature and plasma rotation velocity during the neutral beam injection. The composite CX spectral data are analyzed by the atomic data and analysis structure charge exchange spectroscopy fitting (ADAS CXSFIT) code. First experimental results are shown for the case of HL-2A plasmas with sawtooth oscillations, electron cyclotron resonance heating, and edge transport barrier during the high-confinement mode (H-mode)

  15. The Production of Negative Lithium Beams by Charge Exchange in Cesium Vapours

    CERN Document Server

    Re, Maurizio; Chines, Francesco; Cuttone, Giacomo; Menna, Mariano; Messina, Esteban; Stracener, Dan

    2005-01-01

    These measurements were carried out at the Holifield Radioactive Ion Beam Facility of the Oak Ridge National Laboratory (ORNL-HRIBF) by researchers from the Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS), Catania, Italy and local staff. The Charge Exchange Cell (CEC) consisted of a vacuum chamber containing cesium vapours at a variable temperature, T, in which positive ions accelerated from an ion source were transformed into negative ones by collisions with the Cs atoms. The main goal of this test was to measure the production efficiency for 7Li- ions at different operating conditions, such as 7Li+ beam energy (5 to 55 keV) and Cs temperature (190 to 300 °C). Moreover, the efficiency measurements performed with a 6Li+ projectile beam gave clear indications about the isotopic shift effect. These results are useful to estimate the charge exchange efficiency for 8, 9Li, which will be the first radioactive beams to be produced at the EXCYT facility (EXotics with CYclotro...

  16. Excitation of the Delta(1232) isobar in deuteron charge exchange on hydrogen at 1.6, 1.8, and 2.3 GeV

    CERN Document Server

    Mchedlishvili, D; Carbonell, J; Chiladze, D; Dymov, S; Dzyuba, A; Engels, R; Gebel, R; Glagolev, V; Grigoryev, K; Goslawski, P; Hartmann, M; Imambekov, O; Kacharava, A; Kamerdzhiev, V; Keshelashvili, I; Khoukaz, A; Komarov, V; Kulessa, P; Kulikov, A; Lehrach, A; Lomidze, N; Lorentz, B; Macharashvili, G; Maier, R; Merzliakov, S; Mielke, M; Mikirtychyants, M; Mikirtychyants, S; Nioradze, M; Ohm, H; Papenbrock, M; Prasuhn, D; Rathmann, F; Serdyuk, V; Seyfarth, H; Stein, H J; Steffens, E; Stockhorst, H; Ströher, H; Tabidze, M; Trusov, S; Uzikov, Yu; Valdau, Yu; Wilkin, C

    2013-01-01

    The charge-exchange break-up of polarised deuterons pol{d}p -> {pp}n, where the final {pp} diproton system has a very low excitation energy and hence is mainly in the 1S0 state, is a powerful tool to probe the spin-flip terms in the proton-neutron charge-exchange scattering. Recent measurements with the ANKE spectrometer at the COSY storage ring at 1.6, 1.8, and 2.27 GeV have extended these studies into the pion-production regime in order to investigate the mechanism for the excitation of the Delta(1232) isobar in the pol{d}p -> {pp}X reaction. Values of the differential cross section and two deuteron tensor analysing powers, A_{xx} and A_{yy}, have been extracted in terms of the momentum transfer to the diproton or the invariant mass Mx of the unobserved system X. The unpolarised cross section in the high Mx region is well described in a model that includes only direct excitation of the Delta isobar through undistorted one pion exchange. However, the cross section is grossly underestimated for low Mx, even w...

  17. Folding model study of the charge-exchange scattering to the isobaric analog state and implication for the nuclear symmetry energy

    CERN Document Server

    Khoa, Dao T; Thang, Dang Ngoc

    2013-01-01

    The Fermi transition (\\Delta L=\\Delta S=0 and \\Delta T=1) between the nuclear isobaric analog states (IAS), induced by the charge-exchange (p,n) or (3He,t) reaction, can be considered as "elastic" scattering of proton or 3He by the isovector term of the optical potential (OP) that flips the projectile isospin. The accurately measured (p,n) or (3He,t) scattering cross-section to the IAS can be used, therefore, to probe the isospin dependence of the proton or 3He optical potential. Within the folding model, the isovector part of the OP is determined exclusively by the neutron-proton difference in the nuclear densities and the isospin dependence of the effective nucleon-nucleon (NN) interaction. Because the isovector coupling explicitly links the isovector part of the proton or 3He optical potential to the cross section of the charge-exchange (p,n) or (3He,t) scattering to the IAS, the isospin dependence of the effective (in-medium) NN interaction can be well tested in the folding model analysis of these charge-...

  18. Reactor antineutrino fluxes - status and challenges

    CERN Document Server

    Huber, Patrick

    2016-01-01

    In this contribution we describe the current understanding of reactor antineutrino fluxes and point out some recent developments. This is not intended to be a complete review of this vast topic but merely a selection of observations and remarks, which despite their incompleteness, will highlight the status and the challenges of this field.

  19. Estimation of Charge Exchange Recombination Emission Based on Diagnostic Neutral Beam on the Experimental Advanced Superconducting Tokamak

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xian-Mei; WAN Bao-Nian; WU Zhen-Wei

    2007-01-01

    Diagnostic neutral beam (DNB) attenuation and charge exchange recombination emission are estimated on EAST tokamak. Approximately 40% of the beam with the energy of 50 keV can reach the plasma centre (r = 0) for the typical parameters of the Experimental Advanced Superconducting Tokamak (EAST) plasma. Emissivities of CVI (n = 8 → 7, 529.0nm) and OVⅢ (n = 10 → 9, 607.0 nm) visible charge exchange recombination emissions based on the DNB are estimated. The emissivities of the visible bremsstrahlung emission near this wavelength are also calculated for comparison. The results show that the charge exchange recombination emission is about two orders of magnitude greater than the bremsstrahlung emission. It is theoretically indicated that the ratio of signal of charge exchange recombination spectroscopy to the noise from background bremsstrahlung emission,S/N, is large enough in the EAST tokamak with the typical designed parameters. The present results are helpful for experiment design of charge-exchange recombination spectroscopy based on the DNB in the EAST tokamak.

  20. Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay.

    Science.gov (United States)

    An, F P; Balantekin, A B; Band, H R; Bishai, M; Blyth, S; Butorov, I; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J H; Cheng, J; Cheng, Y P; Cherwinka, J J; Chu, M C; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dove, J; Draeger, E; Dwyer, D A; Edwards, W R; Ely, S R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, X H; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, L M; Hu, L J; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lei, R T; Leitner, R; Leung, K Y; Leung, J K C; Lewis, C A; Li, D J; Li, F; Li, G S; Li, Q J; Li, S C; Li, W D; Li, X N; Li, X Q; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, P Y; Lin, S K; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, H; Liu, J L; Liu, J C; Liu, S S; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Martinez Caicedo, D A; McDonald, K T; McKeown, R D; Meng, Y; Mitchell, I; Monari Kebwaro, J; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Pan, H-R; Park, J; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, B; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Shao, B B; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Tsang, K V; Tull, C E; Tung, Y C; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, Q; Xia, D M; Xia, J K; Xia, X; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C G; Yang, L; Yang, M S; Yang, M T; Ye, M; Yeh, M; Young, B L; Yu, G Y; Yu, Z Y; Zang, S L; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, Y M; Zhang, Y X; Zhang, Y M; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y F; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-02-12

    This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9 GWth nuclear reactors with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296 721 and 41 589 inverse β decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55±0.04) ×10(-18)  cm(2) GW(-1) day(-1) or (5.92±0.14) ×10(-43)  cm(2) fission(-1). This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946±0.022 (0.991±0.023) relative to the flux predicted with the Huber-Mueller (ILL-Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2σ over the full energy range with a local significance of up to ∼4σ between 4-6 MeV. A reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions.

  1. High resolution main-ion charge exchange spectroscopy in the DIII-D H-mode pedestal

    Science.gov (United States)

    Grierson, B. A.; Burrell, K. H.; Chrystal, C.; Groebner, R. J.; Haskey, S. R.; Kaplan, D. H.

    2016-11-01

    A new high spatial resolution main-ion (deuterium) charge-exchange spectroscopy system covering the tokamak boundary region has been installed on the DIII-D tokamak. Sixteen new edge main-ion charge-exchange recombination sightlines have been combined with nineteen impurity sightlines in a tangentially viewing geometry on the DIII-D midplane with an interleaving design that achieves 8 mm inter-channel radial resolution for detailed profiles of main-ion temperature, velocity, charge-exchange emission, and neutral beam emission. At the plasma boundary, we find a strong enhancement of the main-ion toroidal velocity that exceeds the impurity velocity by a factor of two. The unique combination of experimentally measured main-ion and impurity profiles provides a powerful quasi-neutrality constraint for reconstruction of tokamak H-mode pedestals.

  2. Charge-exchange, ionization and excitation in low-energy Li$^{+}-$ Ar, K$^{+}-$ Ar, and Na$^{+}-$He collisions

    CERN Document Server

    Lomsadze, Ramaz A; Kezerashvili, RomanYa; Schulz, Michael

    2016-01-01

    Absolute cross sections are measured for charge-exchange, ionization, and excitation within the same experimental setup for the Li$^{+}-$Ar, K$^{+}-$ Ar, and Na$^{+}-$ He collisions in the ion energy range $0.5-10$ keV. Results of our measurements along with existing experimental data and the schematic correlation diagrams are used to analyze and determine the mechanisms for these processes. The experimental results show that the charge-exchange processes are realized with high probabilities and electrons are predominately captured in ground states. The cross section ratio for charge exchange, ionization and excitation processes roughly attains the value $10:2:1$, respectively. The contributions of various partial inelastic channels to the total ionization cross sections are estimated and a primary mechanism for the process is defined. The energy-loss spectrum, in addition, is applied to estimate the relative contribution of different inelastic channels and to determine the mechanisms for the ionization and f...

  3. Atmospheric Lithosphere-Ionosphere Charge Exchange (ALICE) for coupling between earthquake regions, clouds and the ionosphere

    Science.gov (United States)

    Harrison, Giles; Aplin, Karen; Rycroft, Michael

    2014-05-01

    Atmospheric Lithosphere-Ionosphere Charge Exchange (ALICE) has been proposed as a mechanism to link seismic activity and ionospheric changes detected overhead, which has been observed in data obtained by the DEMETER spacecraft. The ALICE mechanism can explain changes in the natural extremely low frequency (ELF) radio noise observed by DEMETER nocturnally before major earthquakes. ALICE operates through the vertical fair weather current density of global atmospheric electricity, through the modification of surface layer ionisation rates and the associated current flow to the ionosphere. These ideas are extended here to include possible effects on layer clouds through which the current density passes. Specifically, we estimate possible layer cloud changes for changes in surface layer ionisation known in some earthquakes.

  4. Collectivity Embedded in Complex Spectra Example of Nuclear Double-Charge Exchange Modes

    CERN Document Server

    Drozdz, S; Speth, J; Wójcik, M

    1997-01-01

    The mechanism of collectivity coexisting with chaos is investigated on the quantum level. The complex spectra are represented in the basis of two-particle two-hole states describing the nuclear double-charge exchange modes in $^{48}$Ca. An example of $J^{\\pi}=0^-$ excitations shows that the residual interaction, which generically implies chaotic behavior, under certain specific and well identified conditions may create transitions stronger than those corresponding to the pure mean-field picture. Therefore, for this type of excitations such an effect is not generic and in most cases the strength of transitions is likely to take much lower values, even close to the Porter-Thomas distributed.

  5. Localized description of surface energy gap effects in the resonant charge exchange between atoms and surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias-Garcia, A; Garcia, Evelina A; Goldberg, E C, E-mail: aiglesiasg@santafe-conicet.gov.ar [Instituto de Desarrollo Tecnologico para la Industria Quimica (INTEC-CONICET-UNL), Gueemes 3450, CC91, (S3000GLN) Santa Fe (Argentina)

    2011-02-02

    The resonant charge exchange between atoms and surfaces is described by considering a localized atomistic view of the solid within the Anderson model. The presence of a surface energy gap is treated within a simplified tight-binding model of the solid, and a proper calculation of the Hamiltonian terms based on a LCAO expansion of the solid eigenstates is performed. It is found that interference terms jointly with a surface projected gap maximum at the {Gamma} point and the Fermi level inside it, lead to hybridization widths negligible around the Fermi level. This result can explain experimental observations related to long-lived adsorbate states and anomalous neutral fractions of low energy ions in alkali/Cu(111) systems.

  6. Models of Heliospheric solar wind charge exchange X-ray emission

    Science.gov (United States)

    Koutroumpa, Dimitra

    2016-04-01

    The first models of the solar wind charge exchange (SWCX) X-ray production in the heliosphere were developed shortly after the discovery of SWCX emission at the end of 1990s. Since then, continuous monitoring of the global solar wind evolution through the solar cycle has allowed better constraints on its interaction with the interstellar neutrals. We have a fairly accurate description of the interstellar neutral density distributions in interplanetary space. However, the solar wind heavy ion fluxes, and especially their short term variability and propagation through interplanetary space, have remained relatively elusive due to the sparseness or lack of in situ data, especially towards high ecliptic latitudes. In this talk, I will present a summary the heliospheric SWCX modeling efforts, and an overview of the global solar cycle variability of heliospheric SWCX emission, while commenting on the difficulties of modeling the real-time variability of the heliospheric X-ray signal.

  7. Correlation of Resonance Charge Exchange Cross-Section Data in the Low-Energy Range

    Science.gov (United States)

    Sheldon, John W.

    1962-01-01

    During the course of a literature survey concerning resonance charge exchange, an unusual degree of agreement was noted between an extrapolation of the data reported by Kushnir, Palyukh, and Sena and the data reported by Ziegler. The data of Kushnir et al. are for ion-atom relative energies from 10 to 1000 ev, while the data of Ziegler are for a relative energy of about 1 ev. Extrapolation of the data of Kushnir et al. was made in accordance with Holstein's theory, 3 which is a combination of time-dependent perturbation methods and classical orbit theory. The results of this theory may be discussed in terms of a critical impact parameter b(sub c).

  8. A kinetic control of the heliospheric interface hydrodynamics of charge-exchanging fluids

    CERN Document Server

    Fahr, H J

    2004-01-01

    It is well known that the Solar System is presently moving through a partially ionized local interstellar medium. This gives rise to a counter-flow situation requiring a consistent description of behaviour of the two fluids -- ions and neutral atoms -- which are dynamically coupled by mutual charge exchange processes. Solutions to this problem have been offered in the literature, all relying on the assumption that the proton fluid, even under evidently nonequilibrium conditions, can be expected to stay in a highly-relaxated distribution function given by mono-Maxwellians shifted by the local proton bulk velocity. Here we check the validity of this assumption, calculating on the basis of a Boltzmann-kinetic approach the actually occurring deviations. As we show, especially for low degrees of ionization, $\\xi \\le 0.3$, both the H-atoms and protons involved do generate in the heliospheric interface clearly pronounced deviations from shifted Maxwellians with asymmetrically shaped distribution functions giving ris...

  9. Charge-exchange-induced perturbations of ion and atom distribution functions in the heliospheric interface

    CERN Document Server

    Fahr, H J

    2004-01-01

    Various hydrodynamic models of the heliospheric interface have been presented meanwhile, numerically simulating the interaction of the solar wind plasma bubble with the counterstreaming partially ionized interstellar medium. In these model approaches the resulting interface flows are found by the use of hydrodynamic simulation codes trying to consistently describe the dynamic and thermodynamic coupling of the different interacting fluids of protons, H-atoms and pick-up ions. Within such approaches, the fluids are generally expected to be correctly described by the three lowest velocity moments, i.e., by shifted Maxwellians. We shall show that in these approaches the charge-exchange-induced momentum coupling is treated in an unsatisfactory representation valid only at supersonic differential flow speeds. Though this flaw can be removed by an improved coupling term, we shall further demonstrate that the assumption of shifted Maxwellians in some regions of the interface is insufficiently well fulfilled both for ...

  10. Recent Advances in Computational Studies of Charge Exchange X-ray Emission

    Science.gov (United States)

    Cumbee, Renata

    2016-06-01

    Interest in astrophysical sources of charge exchange (CX) has grown since X-ray emission from comet Hyakutake was first observed, the origin of which is primarily due to CX processes between neutral species in the comet’s atmosphere and highly charged ions from the solar wind. More recent observations have shown that CX may have a significant contribution to the X-ray emission spectra of a wide variety of environments within our solar system including solar wind charge exchange (SWCX) with neutral gases in the heliosphere and in planetary atmospheres, as well as beyond the solar system in galaxy clusters, supernova remnants, and star forming galaxies.While the basic process of CX has been studied for many decades, the reliability of the existing data is not uniform, and the coverage of the astrophysically important projectile and target combinations and collisional velocities is insufficient. The need for reliable and robust CX X-ray emission models will only be amplified with the with the high resolution X-ray spectra expected from the soft X-ray imaging calorimeter spectrometer (SXS) onboard the Hitomi X-ray observatory. In this talk, I will discuss recent advances in theoretical CX cross sections and X-ray modeling with a focus on CX diagnostics. The need for experimental X-ray spectra and cross sections for benchmarking current theory will also be highlighted. This work was performed in collaboration with David Lyons, Patrick Mullen, David Schultz, Phillip Stancil, and Robin Shelton. Work at UGA was partially supported by NASA grant NNX09AC46G.

  11. Kinetic theory and atomic physics corrections for determination of ion velocities from charge-exchange spectroscopy

    Science.gov (United States)

    Muñoz Burgos, J. M.; Burrell, K. H.; Solomon, W. M.; Grierson, B. A.; Loch, S. D.; Ballance, C. P.; Chrystal, C.

    2013-09-01

    Charge-exchange spectroscopy is a powerful diagnostic tool for determining ion temperatures, densities and rotational velocities in tokamak plasmas. This technique depends on detailed understanding of the atomic physics processes that affect the measured apparent velocities with respect to the true ion rotational velocities. These atomic effects are mainly due to energy dependence of the charge-exchange cross-sections, and in the case of poloidal velocities, due to gyro-motion of the ion during the finite lifetime of the excited states. Accurate lifetimes are necessary for correct interpretation of measured poloidal velocities, specially for high density plasma regimes on machines such as ITER, where l-mixing effects must be taken into account. In this work, a full nl-resolved atomic collisional radiative model coupled with a full kinetic calculation that includes the effects of electric and magnetic fields on the ion gyro-motion is presented for the first time. The model directly calculates from atomic physics first principles the excited state lifetimes that are necessary to evaluate the gyro-orbit effects. It is shown that even for low density plasmas where l-mixing effects are unimportant and coronal conditions can be assumed, the nl-resolved model is necessary for an accurate description of the gyro-motion effects to determine poloidal velocities. This solution shows good agreement when compared to three QH-mode shots on DIII-D, which contain a wide range of toroidal velocities and high ion temperatures where greater atomic corrections are needed. The velocities obtained from the model are compared to experimental velocities determined from co- and counter-injection of neutral beams on DIII-D.

  12. Solar wind charge exchange emission in the Chandra deep field north

    International Nuclear Information System (INIS)

    The diffuse soft X-ray background comes from distant galaxies, from hot Galactic gas, and from within the solar system. The latter emission arises from charge exchange between highly charged solar wind ions and neutral gas. This so-called solar wind charge exchange (SWCX) emission is spatially and temporally variable and interferes with our measurements of more distant cosmic emission while also providing important information on the nature of the solar wind-interstellar medium interaction. We present the results of our analysis of eight Chandra observations of the Chandra Deep Field North (CDFN) with the goal of measuring the cosmic and SWCX contributions to the X-ray background. Our modeling of both geocoronal and heliospheric SWCX emission is the most detailed for any observation to date. After allowing for ∼30% uncertainty in the SWCX emission and subtracting it from the observational data, we estimate that the flux of cosmic background for the CDFN in the O VII Kα, Kβ, and O VIII Lyα lines totals 5.8 ± 1.1 photons s–1 cm–2 sr–1 (or LU). Heliospheric SWCX emission varied for each observation due to differences in solar wind conditions and the line of sight through the solar system, but was typically about half as strong as the cosmic background (i.e., one-third of the total) in those lines. The modeled geocoronal emission was 0.82 LU in one observation but averaged only 0.15 LU in the others. Our measurement of the cosmic background is lower than but marginally consistent with previous estimates based on XMM-Newton data.

  13. The charge-exchange induced coupling between plasma-gas counterflows in the heliosheath

    Directory of Open Access Journals (Sweden)

    H. J. Fahr

    Full Text Available Many hydrodynamic models have been presented which give similar views of the interaction of the solar wind plasma bubble with the counterstreaming partially ionized interstellar medium. In the more recent of these models it is taken into account that the solar and interstellar hydrodynamic flows of neutral atoms and protons are coupled by mass-, momentum-, and energy-exchange terms due to charge exchange processes. We shall reinvestigate the theoretical basis of this coupling here by use of a simplified description of the heliospheric interface and describe the main physics of the H-atom penetration through the more or less standing well-known plasma wall ahead of the heliopause. Thereby we can show that the type of charge exchange coupling terms used in up-to-now hydrodynamic treatments unavoidably leads to an O-type critical point at the sonic point of the H-atom flow, thus not allowing for a continuation of the integration of the hydrodynamic set of differential equations. The remedy for this problem is given by a more accurate formulation of the momentum exchange term for quasi-and sub-sonic H-atom flows. With a refined momentum exchange term derived from basic kinetic Boltzmann principles, we instead arrive at a characteristic equation with an X-type critical point, allowing for a continuous solution from supersonic to subsonic flow conditions. This necessitates that the often treated problem of the propagation of inter-stellar H-atoms through the heliosheath has to be solved using these newly derived, differently effective plasma – gas friction forces. Substantially different results are to be expected from this context for the filtration efficiency of the heliospheric interface.

    Key words. Interplanetary physics (heliopause and solar wind termination; interstellar gas – Ionosphere (plasma temperature and density

  14. Wall reflection modeling for charge exchange recombination spectroscopy (CXRS) measurements on Textor and ITER

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Santanu; Vasu, P [Institute for Plasma Research, Bhat, Gandhinagar 382 428, Gujarat (India); Von Hellermann, M [FOM Institute for Plasma Physics, Rijnhuizen (Netherlands); Jaspers, R J E, E-mail: sbanerje@ipr.res.i [Applied Physics Department, Eindhoven University of Technology, Eindhoven (Netherlands)

    2010-12-15

    Contamination of optical signals by reflections from the tokamak vessel wall is a matter of great concern. For machines such as ITER and future reactors, where the vessel wall will be predominantly metallic, this is potentially a risk factor for quantitative optical emission spectroscopy. This is, in particular, the case when bremsstrahlung continuum radiation from the bulk plasma is used as a common reference light source for the cross-calibration of visible spectroscopy. In this paper the reflected contribution to the continuum level in Textor and ITER has been estimated for the detection channels meant for charge exchange recombination spectroscopy (CXRS). A model assuming diffuse reflection has been developed for the bremsstrahlung which is a much extended source. Based on this model, it is shown that in the case of ITER upper port 3, a wall with a moderate reflectivity of 20% leads to the wall reflected fraction being as high as 55-60% of the weak signals in the edge channels. In contrast, a complete bidirectional reflectance distribution function (BRDF) based model has been developed in order to estimate the reflections from more localized sources like the charge exchange (CX) emission from a neutral beam in tokamaks. The largest signal contamination of {approx}15% is seen in the core CX channels, where the true CX signal level is much lower than that in the edge channels. Similar values are obtained for Textor also. These results indicate that the contributions from wall reflections may be large enough to significantly distort the overall spectral features of CX data, warranting an analysis at different wavelengths.

  15. Wall reflection modeling for charge exchange recombination spectroscopy (CXRS) measurements on Textor and ITER

    Science.gov (United States)

    Banerjee, Santanu; Vasu, P.; von Hellermann, M.; Jaspers, R. J. E.

    2010-12-01

    Contamination of optical signals by reflections from the tokamak vessel wall is a matter of great concern. For machines such as ITER and future reactors, where the vessel wall will be predominantly metallic, this is potentially a risk factor for quantitative optical emission spectroscopy. This is, in particular, the case when bremsstrahlung continuum radiation from the bulk plasma is used as a common reference light source for the cross-calibration of visible spectroscopy. In this paper the reflected contribution to the continuum level in Textor and ITER has been estimated for the detection channels meant for charge exchange recombination spectroscopy (CXRS). A model assuming diffuse reflection has been developed for the bremsstrahlung which is a much extended source. Based on this model, it is shown that in the case of ITER upper port 3, a wall with a moderate reflectivity of 20% leads to the wall reflected fraction being as high as 55-60% of the weak signals in the edge channels. In contrast, a complete bidirectional reflectance distribution function (BRDF) based model has been developed in order to estimate the reflections from more localized sources like the charge exchange (CX) emission from a neutral beam in tokamaks. The largest signal contamination of ~15% is seen in the core CX channels, where the true CX signal level is much lower than that in the edge channels. Similar values are obtained for Textor also. These results indicate that the contributions from wall reflections may be large enough to significantly distort the overall spectral features of CX data, warranting an analysis at different wavelengths.

  16. Precisely determined the spent nuclear fuel antineutrino flux and spectrum for Daya Bay antineutrino experiment

    CERN Document Server

    Ma, X B; Chen, Y X; Zhong, W L; An, F P

    2015-01-01

    Spent nuclear fuel (SNF) antineutrino flux is an important source of uncertainties for a reactor neutrino flux prediction. However, if one want to determine the contribution of spent fuel, many data are needed, such as the amount of spent fuel in the pool, the time after discharged from the reactor core, the burnup of each assembly, and the antineutrino spectrum of the isotopes in the spend fuel. A method to calculate the contribution of SNF is proposed in this study. In this method, reactor simulation code verified by experiment have been used to simulate the fuel depletion by taking into account more than 2000 isotopes and fission products, the quantity of SNF in each six spend fuel pool, and the antineutrino spectrum of SNF varying with time after SNF discharged from core. Results show that the contribution of SNF to the total antineutrino flux is about 0.26%~0.34%, and the shutdown impact is about 20%. The SNF spectrum would distort the softer part of antineutrino spectra, and the maximum contribution fro...

  17. NUMEN Project @ LNS : Heavy Ions Double Charge Exchange as a tool towards the 0νββ Nuclear Matrix Element

    Science.gov (United States)

    Agodi, C.; Cappuzzello, F.; Bonanno, D. L.; Bongiovanni, D. G.; Branchina, V.; Calabrese, S.; Calabretta, L.; Calanna, A.; Carbone, D.; Cavallaro, M.; Colonna, M.; Foti, A.; Finocchiaro, P.; Greco, V.; Lanzalone, G.; Lo Presti, D.; Longhitano, F.; Muoio, A.; Pandola, L.; Rifuggiato, D.; Tudisco, S.

    2016-06-01

    The NUMEN Project, proposed at INFN Laboratori Nazionali del Sud (LNS) in Catania, has the aim to access the nuclear matrix elements, entering the expression of the life time of double beta decay, by relevant cross sections of double charge exchange reactions. The basic point, on which it is based this innovative technique, is the coincidence of the initial and final state wave-functions in the two classes of processes and the similarity of the transition operators. A key aspect of the Project is the use of MAGNEX large acceptance magnetic spectrometer, for the detection of the ejectiles, and of the INFN LNS K800 Superconducting Cyclotron (CS), for the acceleration of the required high resolution and low emittance heavy-ion beams.

  18. Precision spectroscopy with reactor anti-neutrinos

    CERN Document Server

    Huber, P; Huber, Patrick; Schwetz, Thomas

    2004-01-01

    In this work we present an accurate parameterization of the anti-neutrino flux produced by the isotopes 235U, 239Pu and 241Pu in nuclear reactors. We determine the coefficients of this parameterization, as well as their covariance matrix, by performing a fit to spectra inferred from experimentally measured beta spectra. Subsequently we show that flux shape uncertainties play only a minor role in the KamLAND experiment, however, we find that future reactor neutrino experiments to measure the mixing angle $\\theta_{13}$ are sensitive to the fine details of the reactor neutrino spectra. Finally, we investigate the possibility to determine the isotopic composition in nuclear reactors through an anti-neutrino measurement. We find that with a 3 month exposure of a one ton detector the isotope fractions and the thermal reactor power can be determined at a few percent accuracy, which may open the possibility of an application for safeguard or non-proliferation objectives.

  19. Hanohano:A Deep Ocean Antineutrino Observatory

    CERN Document Server

    Batygov, M; Learned, J G; Matsuno, S; Pakvasa, S; Varner, G

    2008-01-01

    This paper presents the science potential of a deep ocean antineutrino observatory being developed at Hawaii and elsewhere. The observatory design allows for relocation from one site to another. Positioning the observaory some 60 km distant from a nuclear reactor complex enables preecision measurement of neutrino mixing parameters, leading to a determination of neutrino mass hierarchy and theta_13. At a mid-Pacific location, the observatory measures the flux of uranium and thorium decay series antineutrinos from earth's mantle and performs a sensitive search for a hypothetical natural fission reactor in earth's core. A subequent deployment at another mid-ocean location would test lateral homogeneity of uranium and thorium in earth's mantle. These measurements have significance for earth energy studies.

  20. The antineutrino energy structure in reactor experiments

    CERN Document Server

    Novella, P

    2015-01-01

    The recent observation of an energy structure in the reactor antineutrino spectrum is reviewed. The reactor experiments Daya Bay, Double Chooz and RENO have reported a consistent excess of antineutrinos deviating from the flux predictions, with a local significance of about 4$\\sigma$ between 4 and 6 MeV of the positron energy spectrum. The possible causes of the structure are analyzed in this work, along with the different experimental approaches developed to identify its origin. Considering the available data and results from the three experiments, the most likely explanation concerns the reactor flux predictions and the associated uncertainties. Therefore, the different current models are described and compared. The possible sources of incompleteness or inaccuracy of such models are discussed, as well as the experimental data required to improve their precision.

  1. KamLAND, solar antineutrinos and the solar magnetic field

    CERN Document Server

    Chauhan, B C; Torrente-Lujan, E; Chauhan, Bhag C.; Pulido, Joao

    2003-01-01

    In this work the possibility of detecting solar electron antineutrinos produced by a solar core magnetic field from the KamLAND recent observations is investigated. We find a scaling of the antineutrino probability with respect to the magnetic field profile in the sense that the same probability function can be reproduced by any profile with a suitable peak field value. In this way the solar electron antineutrino spectrum can be unambiguosly predicted. We use this scaling and the negative results indicated by the KamLAND experiment to obtain upper bounds on the solar electron antineutrino flux. We get $\\phi_{\\bar\

  2. Theory of Antineutrino Monitoring of Burning MOX Plutonium Fuels

    CERN Document Server

    Hayes, A C; Nieto, Michael Martin; WIlson, W B

    2011-01-01

    This letter presents the physics and feasibility of reactor antineutrino monitoring to verify the burnup of plutonium loaded in the reactor as a Mixed Oxide (MOX) fuel. It examines the magnitude and temporal variation in the antineutrino signals expected for different MOX fuels, for the purposes of nuclear accountability and safeguards. The antineutrino signals from reactor-grade and weapons-grade MOX are shown to be distinct from those from burning low enriched uranium. Thus, antineutrino monitoring could be used to verify the destruction of plutonium in reactors, though verifying the grade of the plutonium being burned is found to be more challenging.

  3. Hanohano:A Deep Ocean Antineutrino Observatory

    OpenAIRE

    Batygov, M.; Dye, S. T.; Learned, J. G.; Matsuno, S; Pakvasa, S.; Varner, G.

    2008-01-01

    This paper presents the science potential of a deep ocean antineutrino observatory being developed at Hawaii and elsewhere. The observatory design allows for relocation from one site to another. Positioning the observaory some 60 km distant from a nuclear reactor complex enables preecision measurement of neutrino mixing parameters, leading to a determination of neutrino mass hierarchy and theta_13. At a mid-Pacific location, the observatory measures the flux of uranium and thorium decay serie...

  4. Cooperative Monitoring of Reactors with Antineutrino Detectors

    Science.gov (United States)

    Keefer, Gregory

    2011-04-01

    LLNL and SNL have been exploiting the unique characteristics of reactor antineutrinos for nearly a decade in an effort to develop an independent means of monitoring fissile material diversion for reactor safeguard programs. The current capabilities of antineutrino detectors used in a non-proliferation regime are such that the operational status, power levels and fissile content of the nuclear reactor can be determined in real-time. These experiments were performed at stand-off distances of a few tens of meters. In the last few years, the International Atomic Energy Agency has begun to consider the potential of this technology for its reactor safeguards regime. In this talk, I describe the state of the art for this application, and emphasize the natural overlap with ongoing efforts in fundamental physics to measure the oscillations of antineutrinos using nuclear reactors as sources. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  5. Charge Exchange Induced X-ray Emission of Fe XXV and Fe XXVI via a Streamlined Model

    CERN Document Server

    Mullen, P D; Lyons, D; Stancil, P C

    2016-01-01

    Charge exchange is an important process for the modeling of X-ray spectra obtained by the Chandra, XMM-Newton, and Suzaku X-ray observatories, as well as the anticipated Astro-H mission. The understanding of the observed X-ray spectra produced by many astrophysical environments is hindered by the current incompleteness of available atomic and molecular data -- especially for charge exchange. Here, we implement a streamlined program set that applies quantum defect methods and the Landau-Zener theory to generate total, n-resolved, and nlS-resolved cross sections for any given projectile ion/ target charge exchange collision. Using this data in a cascade model for X-ray emission, theoretical spectra for such systems can be predicted. With these techniques, Fe25+ and Fe26+ charge exchange collisions with H, He, H2, N2, H2O, and CO are studied for single electron capture. These systems have been selected as they illustrate computational difficulties for high projectile charges. Further, Fe XXV and Fe XXVI emission...

  6. Charge-exchange measurements of fully-stripped oxygen and carbon ion radial density profiles in TFR

    International Nuclear Information System (INIS)

    Fully-ionized oxygen and carbon ions have been detected in TFR via charge-exchange recombination spectroscopy using a modulated auxiliary neutral beam, thus allowing their radial density profiles to be obtained. An impurity transport numerical code is then used to deduce the impurity transport parameters

  7. Suzaku and XMM-Newton Observations of the North Polar Spur: Charge Exchange or ISM Absorption?

    CERN Document Server

    Gu, Liyi; Costantini, Elisa; Kaastra, Jelle

    2016-01-01

    By revisiting the Suzaku and XMM-Newton data of the North Polar Spur, we discovered that the spectra are inconsistent with the traditional model consisting of pure thermal emission and neutral absorption. The most prominent discrepancies are the enhanced O VII and Ne IX forbidden-to-resonance ratios, and a high O VIII Ly$\\beta$ line relative to other Lyman series. A collisionally ionized absorption model can naturally explain both features, while a charge exchange component can only account for the former. By including the additional ionized absorption, the plasma in the North Polar Spur can be described by a single-phase CIE component with temperature of 0.25 keV, and nitrogen, oxygen, neon, magnesium, and iron abundances of $0.4-0.8$ solar. The abundance pattern of the North Polar Spur is well in line with those of the Galactic halo stars. The high nitrogen-to-oxygen ratio reported in previous studies can be migrated to the large transmission of the O VIII Ly$\\alpha$ line. The ionized absorber is characteri...

  8. Solar wind charge exchange X-ray emission from Mars Model and data comparison

    CERN Document Server

    Koutroumpa, Dimitra; Chanteur, Gerard; Chaufray, Jean-Yves; Kharchenko, Vasili; Lallement, Rosine

    2012-01-01

    Aims. We study the soft X-ray emission induced by charge exchange (CX) collisions between solar-wind, highly charged ions and neutral atoms of the Martian exosphere. Methods. A 3D multi species hybrid simulation model with improved spatial resolution (130 km) is used to describe the interaction between the solar wind and the Martian neutrals. We calculated velocity and density distributions of the solar wind plasma in the Martian environment with realistic planetary ions description, using spherically symmetric exospheric H and O profiles. Following that, a 3D test-particle model was developed to compute the X-ray emission produced by CX collisions between neutrals and solar wind minor ions. The model results are compared to XMM-Newton observations of Mars. Results. We calculate projected X-ray emission maps for the XMM-Newton observing conditions and demonstrate how the X-ray emission reflects the Martian electromagnetic structure in accordance with the observed X-ray images. Our maps confirm that X-ray imag...

  9. Modification to poloidal charge exchange recombination spectroscopy measurement in JT-60U tokamak

    Institute of Scientific and Technical Information of China (English)

    Ding Bo-Jiang; Sakamoto Yoshiteru; Miura Yukitoshi

    2007-01-01

    With consideration of the effects of the atomic process and the sight line direction on the charge exchange recombination spectroscopy (CXRS), a code used to modify the poloidal CXRS measurement on Tokamak-60 Upgrade (JT-60U) in Japan Atomic Energy Research Institute is developed, offering an effective tool to modify the measurement and analyse experimental results further. The results show that the poloidal velocity of ion is overestimated but the ion temperature is underestimated by the poloidal CXRS measurement, and they also indicate that the effect of observation angle on rotation velocity is a dominant one in a core region (r/a< 0.65), whereas in an edge region where the sight line is nearly normal to the neutral beam, the observation angle effect is very small. The difference between the modified velocity and the neoclassical velocity is not larger than the error in measurement. The difference inside the internal transport barrier (ITB) region is 2-3 times larger than that outside the ITB region, and it increases when the effect of excited components in neutral beam is taken into account. The radial electric field profile is affected greatly by the poloidal rotation term, which possibly indicates the correlation between the poloidal rotation and the transport barrier formation.

  10. Fragmentation of CO2 molecules in slow charge exchange collisions with Ar8+

    International Nuclear Information System (INIS)

    Charge exchange collisions between multiply charged ions and CO2 have been studied at low collision velocities (E=400 eV/amu). The stability of the ion, produced in different charge states, is analyzed by means of a time-of-flight spectrometer. Recoil ions and fragments are measured in coincidence with projectile ions, which are selected with respect to their charge state and the scattering angle. For large impact parameters the production of singly and doubly charged CO2 ions turns out to be the major process. The opening of one out of two molecular bindings is found to be more likely than the total fragmentation of the molecule. The formation of O+ and CO+ fragments with very small kinetic energies is explained by single electron capture forming CO2+ in the excited (C 2Σg+) state. Collisions with smaller impact parameters and multi-electron capture processes always lead to a total fragmentation of the molecule characterized by a symmetric Coulomb explosion

  11. Charge-exchange Induced Modulation of the Heliosheath Ion Distribution Downstream of the Termination Shock

    Science.gov (United States)

    Fahr, H. J.; Fichtner, H.; Scherer, K.

    2015-12-01

    We consider the evolution of the solar wind ion distribution function alongthe plasma flow downstream from the termination shock induced by chargeexchange processes with cold interstellar H-atoms. We start from a kineticphase space transport equation valid in the bulk frame of the plasma flowthat takes into account convective changes, cooling processes, energydiffusion and ion injection, and describes solar wind and pick-up ionsas a co-moving, isotropic, joint ion population. From this kinetic transportequation one can ascend to an equation for the pressure moment of the iondistribution function, a so-called pressure transport equation, describingthe evolution of the ion pressure in the comoving rest frame. Assuming thatthe local ion distribution can be represented by an adequate kappa functionwith a kappa parameter that varies with the streamline coordinate, weobtain an ordinary differential equation for kappa as function of thestreamline coordinate s. With this result then we gain the heliosheath iondistribution function downstream of the termination shock. The latter thencan be used to predict the Voyager-2 measured moments of the distributionfunction like ion density and ion temperature, and it can also be used topredict spectral fluxes of ENA`s originating from these ions and registeredby IBEX-Hi and IBEX-Lo.We especially analyse the solar wind ion temperature decreasemeasured by Voyager-2 between the years 2008 to 2011 and try to explain itas a charge-exchange induced cooling of the ion distribution function duringthe associated ion convection period.

  12. Chandra Observations and Modeling of Geocoronal Charge Exchange X-Ray Emission During Solar Wind Gusts

    Science.gov (United States)

    Kornbleuth, Marc; Wargelin, Bradford J.; Juda, Michael

    2014-06-01

    Solar wind charge exchange (SWCX) X-rays are emitted when highly charged solar wind ions such as O7+ collide with neutral gas. The best known examples of this occur around comets, but SWCX emission also arises in the Earth's tenuous outer atmosphere and throughout the heliosphere as neutral H and He from the interstellar medium flows into the solar system. This geocoronal and heliospheric emission comprises much of the soft X-ray background and is seen in every X-ray observation. Geocoronal emission, although usually weaker than heliospheric emission, arises within a few tens of Earth radii and therefore responds much more quickly (on time scales of less than an hour) to changes in solar wind intensity than the widely distributed heliospheric emission.We have studied a dozen Chandra observations when the flux of solar wind protons and O7+ ions was at its highest. These gusts of wind cause correspondingly abrupt changes in geocoronal SWCX X-ray emission,which may or may not be apparent in Chandra data depending on a given observation's line of sight through the magnetosphere. We compare observed changes in the X-ray background with predictions from a fully 3D analysis of SWCX emission based on magnetospheric simulations using the BATS-R-US model.

  13. Analysis of the low-energy $\\pi^- p$ charge-exchange data

    CERN Document Server

    Matsinos, Evangelos

    2012-01-01

    We analyse the charge-exchange (CX) measurements $\\pi^- p\\rightarrow \\pi^0 n$ below pion laboratory kinetic energy of 100 MeV. After the removal of five degrees of freedom from the initial database, we combined it with the truncated $\\pi^+ p$ database of our recent PSA and fitted to the data using the ETH model. The set of model-parameter values, as well as the predictions (which are derived on their basis) for the phase shifts and for the low-energy $\\pi N$ constants, are significantly different from the results we obtained in the analysis of the truncated $\\pi^\\pm p$ elastic-scattering databases. Concerning the phase shifts, the main difference occurs in $\\tilde{\\delta}_{0+}^{1/2}$; smaller differences have been found in two p-wave phase shifts. We discuss the implications of these findings in terms of the violation of the isospin invariance in the hadronic part of the $\\pi N$ interaction. The effect observed is at the level of $7-8%$ in the CX scattering amplitude below about 70 MeV. The results and conclu...

  14. Suzaku and XMM-Newton observations of the North Polar Spur: Charge exchange or ISM absorption?

    Science.gov (United States)

    Gu, Liyi; Mao, Junjie; Costantini, Elisa; Kaastra, Jelle

    2016-10-01

    By revisiting the Suzaku and XMM-Newton data of the North Polar Spur, we discovered that the spectra are inconsistent with the traditional model consisting of pure thermal emission and neutral absorption. The most prominent discrepancies are the enhanced O vii and Ne ix forbidden-to-resonance ratios, and a high O viii Lyβ line relative to other Lyman series. A collisionally ionized absorption model can naturally explain both features, while a charge exchange component can only account for the former. By including the additional ionized absorption, the plasma in the North Polar Spur can be described by a single-phase collisional ionization equilibrium (CIE) component with a temperature of 0.25 keV, and nitrogen, oxygen, neon, magnesium, and iron abundances of 0.4-0.8 solar. The abundance pattern of the North Polar Spur is well in line with those of the Galactic halo stars. The high nitrogen-to-oxygen ratio reported in previous studies can be migrated to the large transmission of the O viii Lyα line. The ionized absorber is characterized by a balance temperature of 0.17-0.20 keV and a column density of 3-5 × 1019 cm-2. Based on the derived abundances and absorption, we speculate that the North Polar Spur is a structure in the Galactic halo, so that the emission is mostly absorbed by the Galactic interstellar medium in the line of sight.

  15. Solar Wind Charge Exchange Studies Of Highly Charged Ions On Atomic Hydrogen

    International Nuclear Information System (INIS)

    Accurate studies of low-energy charge exchange (CX) are critical to understanding underlying soft X-ray radiation processes in the interaction of highly charged ions from the solar wind with the neutral atoms and molecules in the heliosphere, cometary comas, planetary atmospheres, interstellar winds, etc.. Particularly important are the CX cross sections for bare, H-like, and He-like ions of C, N, O and Ne, which are the dominant charge states for these heavier elements in the solar wind. Absolute total cross sections for single electron capture by H-like ions of C, N, O and fully-stripped O ions from atomic hydrogen have been measured in an expanded range of relative collision energies (5 eV/u-20 keV/u) and compared to previous H-oven measurements. The present measurements are performed using a merged-beams technique with intense highly charged ion beams extracted from a 14.5 GHz ECR ion source installed on a high voltage platform at the Oak Ridge National Laboratory. For the collision energy range of 0.3 keV/u-3.3 keV/u, which corresponds to typical ion velocities in the solar wind, the new measurements are in good agreement with previous H-oven measurements. The experimental results are discussed in detail and compared with theoretical calculations where available.

  16. Spectral Modeling of the Charge-Exchange X-ray Emission from M82

    CERN Document Server

    Zhang, Shuinai; Ji, Li; Smith, Randall K; Foster, Adam R; Zhou, Xin

    2014-01-01

    It has been proposed that the charge exchange (CX) process at the interface between hot and cool interstellar gases could contribute significantly to the observed soft X-ray emission in star forming galaxies. We analyze the XMM-Newton/RGS spectrum of M82, using a newly developed CX model combined with a single-temperature thermal plasma to characterize the volume-filling hot gas. The CX process is largely responsible for not only the strongly enhanced forbidden lines of the K$\\alpha$ triplets of various He-like ions, but also good fractions of the Ly$\\alpha$ transitions of C VI (~87%), O VIII and N VII ($\\gtrsim$50%) as well. In total about a quarter of the X-ray flux in the RGS 6-30 \\AA\\ band originates in the CX. We infer an ion incident rate of $3\\times10^{51}\\,\\rm{s^{-1}}$ undergoing CX at the hot and cool gas interface, and an effective area of the interface as $\\sim2\\times10^{45}\\,{\\rm cm^2}$ that is one order of magnitude larger than the cross section of the global biconic outflow. With the CX contribu...

  17. Performance of the CERN PSB at 160 MeV with $H^{-}$ charge exchange injection

    CERN Document Server

    AUTHOR|(CDS)2084247; Santoni, Claudio

    As part of the LHC Injectors Upgrade Project, the CERN PS Booster (PSB) will be upgraded with a H- charge exchange injection system and its injection energy will be raised from 50 MeV to 160 MeV to obtain the beam brightness required for the LHC High-Luminosity Upgrade. Space charge effects like beam losses and transverse emittance blow-up at injection are expected to be the main limitations towards the achievement of the required high brightness. Studies of beam dynamics in presence of space charge in order to evaluate the performances of the PSB after the Upgrade have been performed. The first part of the work consists of measurements in the present machine, to study the effects of space charge and its interplay with resonances and to have a good set of data for code benchmarking. The code chosen for the beam tracking in presence of space charge is PTC-Orbit (and PyOrbit). Necessary numerical convergence studies are presented together with a benchmark with the PSB measurements. Once assessed the code and it...

  18. Status of Charge Exchange Cross Section Measurements for Highly Charged Ions on Atomic Hydrogen

    Science.gov (United States)

    Draganic, I. N.; Havener, C. C.; Schultz, D. R.; Seely, D. G.; Schultz, P. C.

    2011-05-01

    Total cross sections of charge exchange (CX) for C5+, N6+, and O7+ ions on ground state atomic hydrogen are measured in an extended collision energy range of 1 - 20,000 eV/u. Absolute CX measurements are performed using an improved merged-beams technique with intense highly charged ion beams extracted from a 14.5 GHz ECR ion source mounted on a high voltage platform. In order to improve the problematic H+ signal collection for these exoergic CX collisions at low relative energies, a new double focusing electrostatic analyzer was installed. Experimental CX data are in good agreement with all previous H-oven relative measurements at higher collision energies. We compare our results with the most recent molecular orbital close-coupling (MOCC) and atomic orbital close-coupling (AOCC) theoretical calculations. Work supported by the NASA Solar & Heliospheric Physics Program NNH07ZDA001N, the Office of Fusion Energy Sciences and the Division of Chemical Sciences, Geosciences, and Biosciences, and the Office of Basic Energy Sciences of the U.S. DoE.

  19. Solar Wind Charge Exchange Studies Of Highly Charged Ions On Atomic Hydrogen

    Science.gov (United States)

    Draganić, I. N.; Seely, D. G.; McCammon, D.; Havener, C. C.

    2011-06-01

    Accurate studies of low-energy charge exchange (CX) are critical to understanding underlying soft X-ray radiation processes in the interaction of highly charged ions from the solar wind with the neutral atoms and molecules in the heliosphere, cometary comas, planetary atmospheres, interstellar winds, etc.. Particularly important are the CX cross sections for bare, H-like, and He-like ions of C, N, O and Ne, which are the dominant charge states for these heavier elements in the solar wind. Absolute total cross sections for single electron capture by H-like ions of C, N, O and fully-stripped O ions from atomic hydrogen have been measured in an expanded range of relative collision energies (5 eV/u-20 keV/u) and compared to previous H-oven measurements. The present measurements are performed using a merged-beams technique with intense highly charged ion beams extracted from a 14.5 GHz ECR ion source installed on a high voltage platform at the Oak Ridge National Laboratory. For the collision energy range of 0.3 keV/u-3.3 keV/u, which corresponds to typical ion velocities in the solar wind, the new measurements are in good agreement with previous H-oven measurements. The experimental results are discussed in detail and compared with theoretical calculations where available.

  20. Feasibility of non-thermal helium measurements with charge exchange spectroscopy on ITER

    Science.gov (United States)

    Kappatou, A.; Delabie, E.; Jaspers, R. J. E.; von Hellermann, M. G.

    2012-04-01

    The use of active charge exchange recombination spectroscopy (CXRS) as a diagnostic for fusion-produced alpha particles on ITER is constrained by the signal-to-noise ratio, which is determined by the intensity of the line of interest, the optical throughput of the diagnostic, the neutral beam penetration, and the intensity of bremsstrahlung radiation. The CX spectral line for fast ions has been modelled together with the expected background emission and we present the signal-to-noise ratios calculated as a function of the diagnostic design parameters. Combining the CXRS data from both the heating and the diagnostic neutral beams on ITER, information on fast ions with energies up to 1 MeV can be obtained for the parameters of the ITER core CXRS diagnostic design. To achieve this, energy binning of the signal is used (100 keV bins or larger), in order to improve the signal-to-noise ratio, with a time resolution of 2 s. The time resolution of the measurement can be improved using a higher throughput spectrometer, but this is ultimately limited by the amount of light from the neutral beam that can be collected. Despite the challenges and the fact that the results are not as optimistic as previously assumed, it is concluded that useful information on fast helium density profiles can be obtained using CXRS on ITER.

  1. Target Mass Monitoring and Instrumentation in the Daya Bay Antineutrino Detectors

    CERN Document Server

    Band, Henry R; Greenler, Lee S; Heeger, Karsten M; Hinrichs, Paul; Kang, Li; Lewis, Christine; Li, Shanfeng; Lin, Shengxin; McFarlane, Michael C; Wang, Wei; Webber, David M; Wei, Yadong; Wise, Thomas; Xiao, Qiang; Yang, Li; Zhang, Zhijian

    2012-01-01

    The Daya Bay experiment measures sin^2 2{\\theta}_13 using functionally identical antineutrino detectors located at distances of 300 to 2000 meters from the Daya Bay nuclear power complex. Each detector consists of three nested fluid volumes surrounded by photomultiplier tubes. These volumes are coupled to overflow tanks on top of the detector to allow for thermal expansion of the liquid. Antineutrinos are detected through the inverse beta decay reaction on the proton-rich scintillator target. A precise and continuous measurement of the detector's central target mass is achieved by monitoring the the fluid level in the overflow tanks with cameras and ultrasonic and capacitive sensors. In addition, the monitoring system records detector temperature and levelness at multiple positions. This monitoring information allows the precise determination of the detectors' effective number of target protons during data taking. We present the design, calibration, installation and in-situ tests of the Daya Bay real-time ant...

  2. Intermediate ionization continua for double charge exchange at high impact energies

    Science.gov (United States)

    Belkić, D.ževad

    1993-05-01

    We investigate the problem of two-electron capture from heliumlike atomic systems by bare nuclei ZP+(ZTe1,e2)i-->(ZPe1,e2)f+ZT at high incident energies, using the four-body formalism of the first- and second-order theories. Our goal is to establish the relative importance of the intermediate ionization continua of the two electrons in comparison with the usual direct path of the double electron transfer. For this purpose we presently introduce the boundary-corrected continuum-intermediate-state (BCIS) approximation, which preserves all the features of two-electron capture as a genuine four-body problem. The proposed second-order theory provides a fully adequate description of the fact that, in an intermediate stage of collision, both electrons move in the field of the two Coulomb centers. The previously devised boundary-corrected first Born (CB1) approximation can be obtained as a further simplification of the BCIS model if the invoked two-electron Coulomb waves are replaced by their long-range logarithmic phase factors defined in terms of the corresponding interaggregate separation R. The BCIS method is implemented on the symmetric resonant double charge exchange in collisions between α particles and He(1s2) at impact energies E>=900 keV. The obtained results for the differential and total cross sections are compared with the available experimental data and satisfactory agreement is recorded. As the incident energy increases, a dramatic improvement is obtained in going from the CB1 to the BCIS approximation, since the latter closely follows the measurement, whereas the former overestimates the observed total cross sections by two orders of magnitude.

  3. Quasi-particle random phase approximation to the charge exchange resonances

    Energy Technology Data Exchange (ETDEWEB)

    Conti, Claudio de [Universidade Estadual Paulista (UNESP), Itapeva, SP (Brazil). Campus Experimental de Itapeva; Carlson, Brett Vern [Centro Tecnico Aeroespacial (CTA/ITA), Sao Jose dos Campos, SP (Brazil). Inst. Tecnologico de Aeronautica. Dept. de Fisica

    2009-07-01

    Full text: The Random Phase Approximation (RPA) is the simplest theory of excited states of a nucleus which admits the possibility that the ground state is not of a purely independent particle character but may contain correlations. It successfully describes many of the low-energy collective excitations of the nucleus. When it is based on the Hartree-Fock-Bogoliubov Approximation or BCS Approximation to the single-particle motion, rather than the Hartree-Fock or BCS one, the RPA becomes the Quasi-Particle RPA (QRPA). Here we have derived and solved the QRPA equations to obtain the Charge-Exchange Resonances, namely, Isobaric Analog State and Gamow-Teller Resonance, to the target nuclei, {sup 48}Ca, {sup 90}Zr, {sup 108}Sn, {sup 110}Sn, {sup 1}'1'2Sn, {sup 1}'1'4Sn, {sup 11}'6Sn, {sup 1}'1'8Sn, {sup 120}Sn, {sup 122}Sn, {sup 124}Sn, {sup 1}'2'6Sn, {sup 1}'2'8Sn, {sup 130}Sn, {sup 130}Sn and {sup 208}Pb. We use the motion equation techniques to develop the QRPA, based on the relativistic BCS approximation to the single-particle motion. When solving the equations of the relativistic QRPA we completely eliminate the negative energy states and the continuous states. As here we are interested in the J{sup {pi}} = 0{sup +} and 1{sup +} excitations, this point was not crucial. However, if we desired a treatment more rigorous of the sum rules would be better to include such contributions, much even so, in the calculations that we made the sum rules had been satisfied above of 90% to both IAS and GTR. We show that IAS and GTR for {sup 48}Ca, {sup 90}Zr, {sup 1}'0{sup 8-130}Sn and {sup 20}'8Pb is well reproduced in the calculations that we carry through. (author)

  4. Spectral modeling of the charge-exchange X-ray emission from M82

    International Nuclear Information System (INIS)

    It has been proposed that the charge-exchange (CX) process at the interface between hot and cool interstellar gases could contribute significantly to the observed soft X-ray emission in star-forming galaxies. We analyze the XMM-Newton/reflection grating spectrometer (RGS) spectrum of M82 using a newly developed CX model combined with a single-temperature thermal plasma to characterize the volume-filling hot gas. The CX process is largely responsible for not only the strongly enhanced forbidden lines of the Kα triplets of various He-like ions but also good fractions of the Lyα transitions of C VI (∼87%), O VIII, and N VII (≳50%) as well. In total about a quarter of the X-ray flux in the RGS 6-30 Å band originates in the CX. We infer an ion incident rate of 3 × 1051 s–1 undergoing CX at the hot and cool gas interface and an effective area of the interface of ∼2 × 1045 cm2 that is one order of magnitude larger than the cross section of the global biconic outflow. With the CX contribution accounted for, the best-fit temperature of the hot gas is 0.6 keV, and the metal abundances are approximately solar. We further show that the same CX/thermal plasma model also gives an excellent description of the EPIC-pn spectrum of the outflow Cap, projected at 11.6 kpc away from the galactic disk of M82. This analysis demonstrates that the CX is potentially an important contributor to the X-ray emission from starburst galaxies and also an invaluable tool to probe the interface astrophysics.

  5. The TFTR E Parallel B Spectrometer for Mass and Energy Resolved Multi-Ion Charge Exchange Diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    A.L. Roquemore; S.S. Medley

    1998-01-01

    The Charge Exchange Neutral Analyzer diagnostic for the Tokamak Fusion Test Reactor was designed to measure the energy distributions of both the thermal ions and the supra thermal populations arising from neutral-beam injection and ion cyclotron radio-frequency heating. These measurements yield the plasma ion temperature, as well as several other plasma parameters necessary to provide an understanding of the plasma condition and the performance of the auxiliary heating methods. For this application, a novel charge-exchange spectrometer using a dee-shaped region of parallel electric and magnetic fields was developed at the Princeton Plasma Physics Laboratory. The design and performance of this spectrometer is described in detail, including the effects of exposure of the microchannel plate detector to magnetic fields, neutrons, and tritium.

  6. Method to obtain absolute impurity density profiles combining charge exchange and beam emission spectroscopy without absolute intensity calibrationa)

    Science.gov (United States)

    Kappatou, A.; Jaspers, R. J. E.; Delabie, E.; Marchuk, O.; Biel, W.; Jakobs, M. A.

    2012-10-01

    Investigation of impurity transport properties in tokamak plasmas is essential and a diagnostic that can provide information on the impurity content is required. Combining charge exchange recombination spectroscopy (CXRS) and beam emission spectroscopy (BES), absolute radial profiles of impurity densities can be obtained from the CXRS and BES intensities, electron density and CXRS and BES emission rates, without requiring any absolute calibration of the spectra. The technique is demonstrated here with absolute impurity density radial profiles obtained in TEXTOR plasmas, using a high efficiency charge exchange spectrometer with high etendue, that measures the CXRS and BES spectra along the same lines-of-sight, offering an additional advantage for the determination of absolute impurity densities.

  7. Method to obtain absolute impurity density profiles combining charge exchange and beam emission spectroscopy without absolute intensity calibration

    Energy Technology Data Exchange (ETDEWEB)

    Kappatou, A.; Delabie, E. [FOM Institute DIFFER - Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, 3430 BE Nieuwegein (Netherlands); Jaspers, R. J. E.; Jakobs, M. A. [Science and Technology of Nuclear Fusion, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Marchuk, O.; Biel, W. [Institute for Energy and Climate Research, Forschungszentrum Julich GmbH, Trilateral Euregio Cluster, 52425 Julich (Germany)

    2012-10-15

    Investigation of impurity transport properties in tokamak plasmas is essential and a diagnostic that can provide information on the impurity content is required. Combining charge exchange recombination spectroscopy (CXRS) and beam emission spectroscopy (BES), absolute radial profiles of impurity densities can be obtained from the CXRS and BES intensities, electron density and CXRS and BES emission rates, without requiring any absolute calibration of the spectra. The technique is demonstrated here with absolute impurity density radial profiles obtained in TEXTOR plasmas, using a high efficiency charge exchange spectrometer with high etendue, that measures the CXRS and BES spectra along the same lines-of-sight, offering an additional advantage for the determination of absolute impurity densities.

  8. Inclusive pion double charge exchange on {sup 16}O at 0.6-1.1 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Abramov, B.M.; Borodin, Yu.A.; Bulychjov, S.A.; Dukhovskoy, I.A.; Kaidalov, A.B.; Krutenkova, A.P.; Kulikov, V.V.; Matsyuk, M.A.; Radkevich, I.A.; Turdakina, E.N.; Alvarez-Ruso, L. E-mail: luis.alvarez-ruso@theo.physik.uni-giessen.de; Vicente Vacas, M.J

    2003-08-11

    The inclusive pion double charge exchange (DCX) on oxygen nuclei has been measured in the region where additional pion production is kinematically forbidden. The experiment was performed at the ITEP PS at incident {pi}{sup -} kinetic energies T{sub 0}=0.59, 0.75 and 1.1 GeV. The integrated forward differential cross section was found to decrease with energy slowly. At 1.1 GeV it exceeds the theoretical prediction within the conventional sequential single charge exchange mechanism with a neutral pion in the intermediate state (Glauber elastic rescattering) by about a factor of five. The sequential mechanism with two pions in the intermediate state (Glauber inelastic rescatterings), which was proposed recently, seems to be able to explain the observed energy dependence and allows to predict the DCX cross section at higher energies.

  9. Inclusive pion double charge exchange on Oxygen(16) at 0.6-1.1 GeV

    CERN Document Server

    Abramov, B M; Bulychjov, S A; Dukhovskoy, I A; Kaidalov, A B; Krutenkova, A P; Kulikov, V V; Matsyuk, M A; Radkevich, I A; Turdakina, E N; Alvarez-Ruso, L; Vacas, M J V; Borodin, Yu.A.

    2003-01-01

    The inclusive pion double charge exchange (DCX) on oxygen nuclei has been measured in the region where additional pion production is kinematically forbidden. The experiment was performed at ITEP PS at incident pi- kinetic energies T_0= 0.59, 0.75 and 1.1 GeV. The integrated forward differential cross section was found to decrease with energy slowly. At 1.1 GeV it exceeds the theoretical prediction within the conventional sequential single charge exchange mechanism with a neutral pion in the intermediate state (Glauber elastic rescattering) by about half an order of magnitude. The sequential mechanism with two pions in the intermediate state (Glauber inelastic rescatterings), which was proposed recently, seems to be able to explain the observed slow energy dependence and allows to predict the DCX cross section for higher energies.

  10. Light-assisted ion-neutral reactive processes in the cold regime: radiative molecule formation vs. charge exchange

    OpenAIRE

    Hall, Felix H. J.; Aymar, Mireille; Bouloufa-Maafa, Nadia; Dulieu, Olivier; Willitsch, Stefan

    2011-01-01

    We present a combined experimental and theoretical study of cold reactive collisions between laser-cooled Ca+ ions and Rb atoms in an ion-atom hybrid trap. We observe rich chemical dynamics which are interpreted in terms of non-adiabatic and radiative charge exchange as well as radiative molecule formation using high-level electronic structure calculations. We study the role of light-assisted processes and show that the efficiency of the dominant chemical pathways is considerably enhanced in ...

  11. Charge-exchange Coupling between Pickup Ions across the Heliopause and its Effect on Energetic Neutral Hydrogen Flux

    Science.gov (United States)

    Zirnstein, E. J.; Heerikhuisen, J.; Zank, G. P.; Pogorelov, N. V.; McComas, D. J.; Desai, M. I.

    2014-03-01

    Pickup ions (PUIs) appear to play an integral role in the multi-component nature of the plasma in the interaction between the solar wind (SW) and local interstellar medium (LISM). Three-dimensional (3D) MHD simulations with a kinetic treatment for neutrals and PUIs are currently still not viable. In light of recent energetic neutral atom (ENA) observations by the Interstellar Boundary EXplorer, the purpose of this paper is to illustrate the complex coupling between PUIs across the heliopause (HP) as facilitated by ENAs using estimates of PUI properties extracted from a 3D MHD simulation of the SW-LISM interaction with kinetic neutrals. First, we improve upon the multi-component treatment of the inner heliosheath (IHS) plasma from Zank et al. by including the extinction of PUIs through charge-exchange. We find a significant amount of energy is transferred away from hot, termination shock-processed PUIs into a colder, "freshly injected" PUI population. Second, we extend the multi-component approach to estimate ENA flux from the outer heliosheath (OHS), formed from charge-exchange between interstellar hydrogen atoms and energetic PUIs. These PUIs are formed from ENAs in the IHS that crossed the HP and experienced charge-exchange. Our estimates, based on plasma-neutral simulations of the SW-LISM interaction and a post-processing analysis of ENAs and PUIs, suggest the majority of flux visible at 1 AU from the front of the heliosphere, between ~0.02 and 10 keV, originates from OHS PUIs, indicating strong coupling between the IHS and OHS plasmas through charge-exchange.

  12. Detection of Breeding Blankets Using Antineutrinos

    Science.gov (United States)

    Cogswell, Bernadette; Huber, Patrick

    2016-03-01

    The Plutonium Management and Disposition Agreement between the United States and Russia makes arrangements for the disposal of 34 metric tons of excess weapon-grade plutonium. Under this agreement Russia plans to dispose of its excess stocks by processing the plutonium into fuel for fast breeder reactors. To meet the disposition requirements this fuel would be burned while the fast reactors are run as burners, i.e., without a natural uranium blanket that can be used to breed plutonium surrounding the core. This talk discusses the potential application of antineutrino monitoring to the verification of the presence or absence of a breeding blanket. It is found that a 36 kg antineutrino detector, exploiting coherent elastic neutrino-nucleus scattering and made of silicon, could determine the presence of a breeding blanket at a liquid sodium cooled fast reactor at the 95% confidence level within 90 days. Such a detector would be a novel non-intrusive verification tool and could present a first application of coherent elastic neutrino-nucleus scattering to a real-world challenge.

  13. Antineutrino reactor safeguards - a case study

    CERN Document Server

    Christensen, Eric; Jaffke, Patrick

    2013-01-01

    Antineutrinos have been proposed as a means of reactor safeguards for more than 30 years and there has been impressive experimental progress in neutrino detection. In this paper we conduct, for the first time, a case study of the application of antineutrino safeguards to a real-world scenario - the North Korean nuclear crisis in 1994. We derive detection limits to a partial or full core discharge in 1989 based on actual IAEA safeguards access and find that two independent methods would have yielded positive evidence for a second core with very high confidence. To generalize our results, we provide detailed estimates for the sensitivity to the plutonium content of various types of reactors, including most types of plutonium production reactors, based on detailed reactor simulations. A key finding of this study is that a wide class of reactors with a thermal power of less than 0.1-1 GWth can be safeguarded achieving IAEA goals for quantitative sensitivity and timeliness with detectors right outside the reactor ...

  14. Charge exchange produced K-shell x-ray emission from Ar16+ in a tokamak plasma with neutral beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Beiersdorfer, P; Bitter, M; Marion, M; Olson, R E

    2004-12-27

    High-resolution spectroscopy of hot tokamak plasma seeded with argon ions and interacting with an energetic, short-pulse neutral hydrogen beam was used to obtain the first high-resolution K-shell x-ray spectrum formed solely by charge exchange. The observed K-shell emission of Ar{sup 16+} is dominated by the intercombination and forbidden lines, providing clear signatures of charge exchange. Results from an ab initio atomic cascade model provide excellent agreement, validating a semiclassical approach for calculating charge exchange cross sections.

  15. Testing Geological Models with Terrestrial Antineutrino Flux Measurements

    CERN Document Server

    Dye, Steve

    2009-01-01

    Uranium and thorium are the main heat producing elements in the earth. Their quantities and distributions, which specify the flux of detectable antineutrinos generated by the beta decay of their daughter isotopes, remain unmeasured. Geological models of the continental crust and the mantle predict different quantities and distributions of uranium and thorium. Many of these differences are resolvable with precision measurements of the terrestrial antineutrino flux. This precision depends on both statistical and systematic uncertainties. An unavoidable background of antineutrinos from nuclear reactors typically dominates the systematic uncertainty. This report explores in detail the capability of various operating and proposed geo-neutrino detectors for testing geological models.

  16. Vector and tensor analysing powers in deuteron-proton breakup reactions at intermediate energies

    CERN Document Server

    Chiladze, D; Dymov, S; Glagolev, V; Hartmann, M; Hejny, V; Kacharava, A K; Keshelashvili, I; Khoukaz, A; Koch, H R; Komarov, V; Kulessa, P; Kulikov, A; Macharashvili, G; Maeda, Y; Mersmann, T; Merzliakov, S; Mikirtytchiants, S; Mussgiller, A; Nioradze, M; Ohm, H; Rathmann, F; Schleichert, R; Stein, H J; Ströher, H; Uzikov, Y; Wilkin, C; Yaschenko, S; Uzikov, Yu.

    2006-01-01

    Vector and tensor analysing powers of the d(pol)p->(pp)n (charge-exchange) and d(pol)p->(pn)p (non-charge-exchange) breakup reactions have been measured with the ANKE spectrometer at the COSY ring at a deuteron beam energy of 1170 MeV for small momentum transfers to the low excitation energy (pp) or (pn) systems. A quantitative understanding of the values of A_xx and A_yy for the charge-exchange reaction is provided by impulse approximation calculations. The data suggest that spin-flip isospin-flip transitions, which dominate the charge-exchange breakup of the deuteron, are also important in the non-charge-exchange reaction.

  17. An improved measurement of muon antineutrino disappearance in MINOS

    CERN Document Server

    Adamson, P; Backhouse, C; Barr, G; Bishai, M; Blake, A; Bock, G J; Boehnlein, D J; Bogert, D; Cao, S V; Childress, S; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; Danko, I Z; de Jong, J K; Devenish, N E; Diwan, M V; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Frohne, M V; Gallagher, H R; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grzelak, K; Habig, A; Hartnell, J; Hatcher, R; Himmel, A; Holin, A; Huang, X; Hylen, J; Irwin, G M; Isvan, Z; Jaffe, D E; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kopp, S; Kordosky, M; Kreymer, A; Lang, K; Ling, J; Litchfield, P J; Loiacono, L; Lucas, P; Mann, W A; Marshak, M L; Mathis, M; Mayer, N; Mehdiyev, R; Meier, J R; Messier, M D; Michael, D G; Miller, W H; Mishra, S R; Mitchell, J; Moore, C D; Mualem, L; Mufson, S; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; Oliver, W P; Orchanian, M; Pahlka, R B; Paley, J; Patterson, R B; Pawloski, G; Phan-Budd, S; Plunkett, R K; Qiu, X; Radovic, A; Ratchford, J; Rebel, B; Rosenfeld, C; Rubin, H A; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Strait, M; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Tinti, G; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Walding, J J; Weber, A; Webb, R C; White, C; Whitehead, L; Wojcicki, S G; Zwaska, R

    2012-01-01

    We report an improved measurement of muon anti-neutrino disappearance over a distance of 735km using the MINOS detectors and the Fermilab Main Injector neutrino beam in a muon anti-neutrino enhanced configuration. From a total exposure of 2.95e20 protons on target, of which 42% have not been previously analyzed, we make the most precise measurement of the anti-neutrino "atmospheric" delta-m squared = 2.62 +0.31/-0.28 (stat.) +/- 0.09 (syst.) and constrain the anti-neutrino atmospheric mixing angle >0.75 (90%CL). These values are in agreement with those measured for muon neutrinos, removing the tension reported previously.

  18. Improved Scintillator Materials For Compact Electron Antineutrino Detectors

    NARCIS (Netherlands)

    Dijkstra, Peter; Wortche, Heinrich J.; Browne, Wesley R.

    2012-01-01

    Recent developments provide new components holding the potential to improve the performance of liquid scintillation electron antineutrino detectors used as nuclear reactors monitors. Current systems raise issues regarding size, quantum efficiency, stability, and spatial resolution of the vertex dete

  19. Estimating terrestrial uranium and thorium by antineutrino flux measurements.

    Science.gov (United States)

    Dye, Stephen T; Guillian, Eugene H

    2008-01-01

    Uranium and thorium within the Earth produce a major portion of terrestrial heat along with a measurable flux of electron antineutrinos. These elements are key components in geophysical and geochemical models. Their quantity and distribution drive the dynamics, define the thermal history, and are a consequence of the differentiation of the Earth. Knowledge of uranium and thorium concentrations in geological reservoirs relies largely on geochemical model calculations. This article describes the methods and criteria to experimentally determine average concentrations of uranium and thorium in the continental crust and in the mantle by using site-specific measurements of the terrestrial antineutrino flux. Optimal, model-independent determinations involve significant exposures of antineutrino detectors remote from nuclear reactors at both a midcontinental and a midoceanic site. This would require major, new antineutrino detection projects. The results of such projects could yield a greatly improved understanding of the deep interior of the Earth.

  20. Estimating terrestrial uranium and thorium by antineutrino flux measurements

    CERN Document Server

    Dye, Stephen T

    2008-01-01

    Uranium and thorium within the Earth produce a major portion of terrestrial heat along with a measurable flux of electron antineutrinos. These elements are key components in geophysical and geochemical models. Their quantity and distribution drive the dynamics, define the thermal history, and are a consequence of the differentiation of the Earth. Knowledge of uranium and thorium concentrations in geological reservoirs relies largely on geochemical model calculations. This research report describes the methods and criteria to experimentally determine average concentrations of uranium and thorium in the continental crust and in the mantle using site-specific measurements of the terrestrial antineutrino flux. Optimal, model-independent determinations involve significant exposures of antineutrino detectors remote from nuclear reactors at both a mid-continental and a mid-oceanic site. This would require major, new antineutrino detection projects. The results of such projects could yield a greatly improved understa...

  1. Geoneutrinos and reactor antineutrinos at SNO+

    CERN Document Server

    Baldoncini, M; Wipperfurth, S A; Fiorentini, G; Mantovani, F; McDonough, W F; Ricci, B

    2016-01-01

    In the heart of the Creighton Mine near Sudbury (Canada), the SNO+ detector is foreseen to observe almost in equal proportion electron antineutrinos produced by U and Th in the Earth and by nuclear reactors. SNO+ will be the first long baseline experiment to measure a reactor signal dominated by CANDU cores ($\\sim$55\\% of the total reactor signal), which generally burn natural uranium. Approximately 18\\% of the total geoneutrino signal is generated by the U and Th present in the rocks of the Huronian Supergroup-Sudbury Basin: the 60\\% uncertainty on the signal produced by this lithologic unit plays a crucial role on the discrimination power on the mantle signal as well as on the geoneutrino spectral shape reconstruction, which can in principle provide a direct measurement of the Th/U ratio in the Earth.

  2. Simulation of the SONGS Reactor Antineutrino Flux Using DRAGON

    CERN Document Server

    Jones, C L

    2011-01-01

    For reactor antineutrino experiments, a thorough understanding of the fuel composition and isotopic evolution is of paramount importance for the extraction of $\\theta_{13}$. To accomplish these goals, we employ the deterministic lattice code DRAGON, and analyze the instantaneous antineutrino rate from the San Onofre Nuclear Generating Station (SONGS) Unit 2 reactor in California. DRAGON's ability to predict the rate for two consecutive fuel cycles is examined.

  3. Testing Geological Models with Terrestrial Antineutrino Flux Measurements

    OpenAIRE

    Dye, Steve

    2009-01-01

    Uranium and thorium are the main heat producing elements in the earth. Their quantities and distributions, which specify the flux of detectable antineutrinos generated by the beta decay of their daughter isotopes, remain unmeasured. Geological models of the continental crust and the mantle predict different quantities and distributions of uranium and thorium. Many of these differences are resolvable with precision measurements of the terrestrial antineutrino flux. This precision depends on bo...

  4. Measurement of the left-right asymmetry in pion-proton radiative exchange and charge exchange scattering from 301 to 625 MeV/c on a transversely polarized target

    International Nuclear Information System (INIS)

    The left-right asymmetry A/sub N/ in π/sup /minus//p → γn has been measured at p/sub π = 301, 316, 427, 471, 547, 586, and 625 MeV/c using a transversely polarized target. The final-state neutron and gamma were detected in coincidence by two states of matching neutron and gamma detectors at gamma angles centered around 90/degree and 110/degree/ c.m. A gamma detector consisted of an array of 15 counters, each was 15/times/15/times/25 cm3 block of lead-glass. A neutron detector consisted of 15 counters also, each one was a cylindrical plastic scintillator 7.6 cm in diameter and 45.7 cm long. The A/sub N/ results are compared with the predictions from the most recent single-pion photoproduction partial-wave analysis by Arai and Fujii. The agreement is poor, casting doubt on the correctness of the value for the radiative-decay amplitude of the neutral Roper resonance now in use. A comparison is made with the 90/degree/recoil proton polarization data of the inverse reaction derived from γd scattering, there are substantial discrepencies. Charge exchange (π/sup /minus/p/ → γ/degree/n) events were the major yield in this experiment. Very precise values of the charge exchange analyzing power were obtained with an error of typically 3%. The charge exchange results are compared with the predictions from recent γn partial wave analyses. At the lower incident energies little difference is seen between the VPI, Karlsruhe-Helsinki, and CMU-LBL analyses, and there is excellent agreement with our experiment. From the onset of the Roper resonance the VPI solution is strongly favored

  5. Local vs. non-local energy loss of low energy ions: Influence of charge exchange processes in close collisions

    Energy Technology Data Exchange (ETDEWEB)

    Primetzhofer, D., E-mail: daniel.primetzhofer@physics.uu.se [Ion Physics, Department of Physics and Astronomy, Ångström Laboratory, Uppsala University, Box 516, S-751 20 Uppsala (Sweden); Goebl, D.; Bauer, P. [Institut für Experimentalphysik, Johannes Kepler Universität Linz, A-4040 Linz (Austria)

    2013-12-15

    We investigate the contribution of charge exchange processes in close collisions between projectile and target atoms to the electronic energy loss of low energy ions. We measure the energy loss of slow hydrogen and He ions in ultrathin Al films through which the ions are transmitted before and after backscattering by the atoms of a Ta substrate. The individual contributions to the energy loss are analyzed. The roles of thresholds for reionization and of scattering kinematics as key parameters for the coupling between elastic and inelastic losses are discussed. The implications of the obtained results for different experimental approaches to deduce stopping cross sections are outlined.

  6. Fast charge exchange spectroscopy using a Fabry-Perot spectrometer in the JIPP TII-U tokamak

    International Nuclear Information System (INIS)

    A new charge exchange spectroscopic technique using a Fabry-Perot spectrometer has been developed to increase the photon flux at the detector and improve the time resolution of ion temperature and plasma rotation velocity measurements. The spectral resolution is obtained by arranging two dimensional fiber optics and a two dimensional detector at the focal plane of a coupled lens located on both sides of a Fabry-Perot spectrometer. The effective finesse of the Fabry-Perot interferometer in this system is 14. The time evolution of the ion temperature is obtained with a time resolution of 125 μs and with the spatial resolution of 3 cm (8 channels). (author)

  7. Charge exchange processes of foil dissociation fragments of fast H+2 ions and H+n clusters

    International Nuclear Information System (INIS)

    We have measured angular and charge state distributions of atomic fragments resulting from the foil dissociation of 30-120 KeV/p H+n clusters. The fragment neutralization probability has been investigated for beam velocities above and around the Bohr velocity. At a given velocity the width of the angular distribution of neutral atoms and their yield are observed to increase with n up to n > 5 and n > 7, respectively. Moreover we have used the simpler H+2 case to propose new ideas to explain the vicinity effects observed on the charge exchange processes

  8. Prospects of real-time ion temperature and rotation profiles based on neural-network charge exchange analysis

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, R.W.T.; Von Hellermann, M. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Svensson, J. [Royal Inst. of Tech., Stockholm (Sweden)

    1994-07-01

    A back-propagation neural network technique is used at JET to extract plasma parameters like ion temperature, rotation velocities or spectral line intensities from charge exchange (CX) spectra. It is shown that in the case of the C VI CX spectra, neural networks can give a good estimation (better than +-20% accuracy) for the main plasma parameters (Ti, V{sub rot}). Since the neural network approach involves no iterations or initial guesses the speed with which a spectrum is processed is so high (0.2 ms/spectrum) that real time analysis will be achieved in the near future. 4 refs., 8 figs.

  9. Cometary Solar Wind Charge Exchange Line Ratios: Source of X-rays in Comet C/2000 WM1 (linear)

    Science.gov (United States)

    Mullen, Patrick Dean; Cumbee, Renata; Lyons, David; Gu, Liyi; Kaastra, Jelle S.; Shelton, Robin L.; Stancil, Phillip C.

    2016-06-01

    Cometary solar wind charge exchange (C-SWCX) occurs when highly charged projectile ions present in solar wind capture an electron from a target neutral species present in the cometary atmosphere. The availability of atomic and molecular data necessary for the X-ray emission modeling due to C-SWCX is limited; therefore, we apply multi-channel Landau-Zener (MCLZ) theory (Mullen et al. 2016) to generate cross section data and theoretical X-ray line ratios for a variety of bare and non-bare ion single electron capture (SEC) collisions. Namely, we consider collisions between the solar wind constituent H-like and He-like ions of C, N, O, Ne, Na, Al, and Si and the cometary neutrals H, H2O, CO, CO2, OH, and O. To exemplify the application of this data, we model the X-ray emission of comet C/2000 WM1 (linear) using the charge exchange package in SPEX (Gu et al. 2015) and find excellent agreement with observations made with the XMM-RGS detector. Our analyses show that the X-ray intensity is dominated by C-SWCX with H.Work at UGA was partially funded by NASA grant NNX13AF31G.References:Gu et al. 2016, A&A, accepted 22 January 2016Mullen et al. 2016, ApJS, in press

  10. STRUCTURE OF THE INTERSTELLAR BOUNDARY EXPLORER RIBBON FROM SECONDARY CHARGE-EXCHANGE AT THE SOLAR–INTERSTELLAR INTERFACE

    Energy Technology Data Exchange (ETDEWEB)

    Zirnstein, E. J.; McComas, D. J. [Southwest Research Institute, San Antonio, TX 78228 (United States); Heerikhuisen, J., E-mail: ezirnstein@swri.edu, E-mail: dmccomas@swri.edu, E-mail: jacob.heerikhuisen@uah.edu [Department of Space Science and Center for Space Plasma and Aeronomic Research, University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

    2015-05-01

    In 2009, the Interstellar Boundary Explorer discovered a bright “ribbon” of energetic neutral atom (ENA) flux in the energy range ≤0.4–6 keV, encircling a large portion of the sky. This observation was not previously predicted by any models or theories, and since its discovery, it has been the subject of numerous studies of its origin and properties. One of the most studied mechanisms for its creation is the “secondary ENA” process. Here, solar wind ions, neutralized by charge-exchange with interstellar atoms, propagate outside the heliopause; experience two charge-exchange events in the dense outer heliosheath; and then propagate back inside the heliosphere, preferentially in the direction perpendicular to the local interstellar magnetic field. This process has been extensively analyzed using state-of-the-art modeling and simulation techniques, but it has been difficult to visualize. In this Letter, we show the three-dimensional structure of the source of the ribbon, providing a physical picture of the spatial and energy scales over which the secondary ENA process occurs. These results help us understand how the ribbon is generated and further supports a secondary ENA process as the leading ribbon source mechanism.

  11. Development of the gas puff charge exchange recombination spectroscopy (GP-CXRS) technique for ion measurements in the plasma edge

    International Nuclear Information System (INIS)

    A novel charge-exchange recombination spectroscopy (CXRS) diagnostic method is presented, which uses a simple thermal gas puff for its donor neutral source, instead of the typical high-energy neutral beam. This diagnostic, named gas puff CXRS (GP-CXRS), is used to measure ion density, velocity, and temperature in the tokamak edge/pedestal region with excellent signal-background ratios, and has a number of advantages to conventional beam-based CXRS systems. Here we develop the physics basis for GP-CXRS, including the neutral transport, the charge-exchange process at low energies, and effects of energy-dependent rate coefficients on the measurements. The GP-CXRS hardware setup is described on two separate tokamaks, Alcator C-Mod and ASDEX Upgrade. Measured spectra and profiles are also presented. Profile comparisons of GP-CXRS and a beam based CXRS system show good agreement. Emphasis is given throughout to describing guiding principles for users interested in applying the GP-CXRS diagnostic technique

  12. Charge exchange and X-ray emission in 70 MeV/u Bi-Au collisions

    Energy Technology Data Exchange (ETDEWEB)

    Verma, P. [GSI, D-64291 Darmstadt (Germany) and Vaish College, Rohtak 124 001 (India) and J. Liebig University, D-35392 Giessen (Germany)]. E-mail: P.Verma@gsi.de; Mokler, P.H. [GSI, D-64291 Darmstadt (Germany); JMI University, New Delhi 110 025 (India); Braeuning-Demian, A. [GSI, D-64291 Darmstadt (Germany); Braeuning, H. [JMI University, New Delhi 110 025 (India); Berdermann, E. [GSI, D-64291 Darmstadt (Germany); Chatterjee, S. [GSI, D-64291 Darmstadt (Germany); Gumberidze, A. [GSI, D-64291 Darmstadt (Germany); Hagmann, S. [J.W. Goethe University, D-60486 Frankfurt (Germany); Kozhuharov, C. [GSI, D-64291 Darmstadt (Germany); Orsic-Muthig, A. [GSI, D-64291 Darmstadt (Germany); Reuschl, R. [J.W. Goethe University, D-60486 Frankfurt (Germany); Schoeffler, M. [J.W. Goethe University, D-60486 Frankfurt (Germany); Spillmann, U. [GSI, D-64291 Darmstadt (Germany); Stoehlker, Th. [GSI, D-64291 Darmstadt (Germany); Stachura, Z. [Institute for Nuclear Physics, PL-31-342 Cracow (Poland); Tashenov, S. [GSI, D-64291 Darmstadt (Germany); Wahab, M.A. [Vaish College, Rohtak 124 001 (India)

    2005-07-01

    Charge exchange and X-ray emission for 70 MeV/u highly charged ions of Bi {sup q+} [77 q 82] colliding with thin Au targets [21 t in {mu}g/cm{sup 2} 225] were measured at the heavy ion synchrotron SIS at GSI. For the innermost shells this beam energy implies a quasiadiabatic collision regime. The charge state distribution of the emerging ions was measured by a position sensitive CVD-diamond detector after being analyzed by a magnet spectrometer. Charge exchange cross sections have been deduced from the target thickness dependence of the charge state distribution. Electron capture at distant collision dominates completely over ionization at close collision. The X-ray emission from the collision partners were measured by solid state detectors, Ge(i). The K X-ray emission for closed and open incoming projectile K vacancies gives access to vacancy transfer in the superheavy quasi-molecule transiently formed during collision for the innermost shells.

  13. Development of the gas puff charge exchange recombination spectroscopy (GP-CXRS) technique for ion measurements in the plasma edge

    Energy Technology Data Exchange (ETDEWEB)

    Churchill, R. M.; Theiler, C.; Lipschultz, B. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Dux, R.; Pütterich, T.; Viezzer, E. [Max-Planck-Institut für Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, D-85748 Garching (Germany); Collaboration: Alcator C-Mod Team; ASDEX Upgrade Team

    2013-09-15

    A novel charge-exchange recombination spectroscopy (CXRS) diagnostic method is presented, which uses a simple thermal gas puff for its donor neutral source, instead of the typical high-energy neutral beam. This diagnostic, named gas puff CXRS (GP-CXRS), is used to measure ion density, velocity, and temperature in the tokamak edge/pedestal region with excellent signal-background ratios, and has a number of advantages to conventional beam-based CXRS systems. Here we develop the physics basis for GP-CXRS, including the neutral transport, the charge-exchange process at low energies, and effects of energy-dependent rate coefficients on the measurements. The GP-CXRS hardware setup is described on two separate tokamaks, Alcator C-Mod and ASDEX Upgrade. Measured spectra and profiles are also presented. Profile comparisons of GP-CXRS and a beam based CXRS system show good agreement. Emphasis is given throughout to describing guiding principles for users interested in applying the GP-CXRS diagnostic technique.

  14. Experimental determination of the antineutrino spectrum of the fission products of {sup 238}U

    Energy Technology Data Exchange (ETDEWEB)

    Haag, Nils-Holger

    2013-10-09

    Fission of {sup 238}U contributes about 10 % to the antineutrino emission of a pressurized water reactor. In the present thesis, the beta spectrum of the fission products of {sup 238}U was determined in an experiment at the neutron source FRM II. This beta spectrum was subsequently converted into an antineutrino spectrum. This first measurement of the antineutrino spectrum supports all current and future reactor antineutrino experiments.

  15. Yale High Energy Physics Research: Precision Studies of Reactor Antineutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Heeger, Karsten M. [Yale Univ., New Haven, CT (United States)

    2014-09-13

    This report presents experimental research at the intensity frontier of particle physics with particular focus on the study of reactor antineutrinos and the precision measurement of neutrino oscillations. The experimental neutrino physics group of Professor Heeger and Senior Scientist Band at Yale University has had leading responsibilities in the construction and operation of the Daya Bay Reactor Antineutrino Experiment and made critical contributions to the discovery of non-zero$\\theta_{13}$. Heeger and Band led the Daya Bay detector management team and are now overseeing the operations of the antineutrino detectors. Postdoctoral researchers and students in this group have made leading contributions to the Daya Bay analysis including the prediction of the reactor antineutrino flux and spectrum, the analysis of the oscillation signal, and the precision determination of the target mass yielding unprecedented precision in the relative detector uncertainty. Heeger's group is now leading an R\\&D effort towards a short-baseline oscillation experiment, called PROSPECT, at a US research reactor and the development of antineutrino detectors with advanced background discrimination.

  16. Progress Towards Deployable Antineutrino Detectors for Reactor Safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Bowden, N; Bernstein, A; Dazeley, S; Keefer, G; Reyna, D; Cabrera-Palmer, B; Kiff, S

    2010-04-05

    Fission reactors emit large numbers of antineutrinos and this flux may be useful for the measurement of two quantities of interest for reactor safeguards: the reactor's power and plutonium inventory throughout its cycle. The high antineutrino flux and relatively low background rates means that simple cubic meter scale detectors at tens of meters standoff can record hundreds or thousands of antineutrino events per day. Such antineutrino detectors would add online, quasi-real-time bulk material accountancy to the set of reactor monitoring tools available to the IAEA and other safeguards agencies with minimal impact on reactor operations. Between 2003 and 2008, our LLNL/SNL collaboration successfully deployed several prototype safeguards detectors at a commercial reactor in order to test both the method and the practicality of its implementation in the field. Partially on the strength of the results obtained from these deployments, an Experts Meeting was convened by the IAEA Novel Technologies Group in 2008 to assess current antineutrino detection technology and examine how it might be incorporated into the safeguards regime. Here we present a summary of our previous deployments and discuss current work that seeks to provide expanded capabilities suggested by the Experts Panel, in particular aboveground detector operation.

  17. KamLAND, solar antineutrinos and their magnetic moment

    CERN Document Server

    Aliani, P; Picariello, M; Torrente-Lujan, E

    2003-01-01

    We investigate the possibility of detecting solar antineutrinos with the KamLAND experiment. These antineutrinos are predicted by spin-flavor oscillations at a significant rate even if this mechanism is not the leading solution to the SNP. The recent evidence from SNO shows that a) the neutrino oscillates, only around 34% of the initial solar neutrinos arrive at the Earth as electron neutrinos and b) the conversion is mainly into active neutrinos, however a non e, mu, tau component is allowed: the fraction of oscillation into non-mu-tau neutrinos is found to be cos^2(alpha) = 0.08^{+0.20}_{-0.40}. This residual flux could include sterile neutrinos and/or the antineutrinos of the active flavors. KamLAND is potentially sensitive to antineutrinos derived from solar ^8 B neutrinos. In case of negative results, we find that KamLAND could put strict limits on the flux of solar antineutrinos, Phi(^8 B) < 1.0 times 10^4 cm^{-2} s^{-1}, more than one order of magnitude smaller than existing limits, and on their app...

  18. Anti-neutrino oscillations with T2K

    CERN Document Server

    Salzgeber, M Ravonel

    2015-01-01

    T2K is a long-baseline neutrino oscillation experiment, in which a muon neutrino beam is produced at J-PARC and detected 295 km away at the Super-Kamiokande detector. The T2K experiment observed electron-neutrino appearance in 2012. This observation enables T2K to explore CP violation in the lepton sector by comparing electron-neutrino appearance and electron-antineutrino appearance. Indeed, the number of observed electron neutrino events up to 2012 is, though within statistical fluctuation, larger than the expectation, which suggests maximal CP violation. Since 2013, T2K has been accumulating data with a muon antineutrino beam. If the suggested maximal CP violation is true, electron-antineutrino appearance would be suppressed. The signal is further suppressed by the smaller cross section for antineutrinos compared to neutrinos. Hence the observation of electron-antineutrino appearance is an important next step. Furthermore, the CPT theorem imposes that the muon disappearance rate must be the same for muon ne...

  19. Integrated readout of organic scintillator and ZnS:Ag/6LiF for segmented antineutrino detectors.

    Energy Technology Data Exchange (ETDEWEB)

    Kiff, Scott D.; Reyna, David; Monahan, James; Bowden, Nathaniel S.

    2010-11-01

    Antineutrino detection using inverse beta decay conversion has demonstrated the capability to measure nuclear reactor power and fissile material content for nuclear safeguards. Current efforts focus on aboveground deployment scenarios, for which highly efficient capture and identification of neutrons is needed to measure the anticipated antineutrino event rates in an elevated background environment. In this submission, we report on initial characterization of a new scintillation-based segmented design that uses layers of ZnS:Ag/{sup 6}LiF and an integrated readout technique to capture and identify neutrons created in the inverse beta decay reaction. Laboratory studies with multiple organic scintillator and ZnS:Ag/{sup 6}LiF configurations reliably identify {sup 6}Li neutron captures in 60 cm-long segments using pulse shape discrimination.

  20. Integrated readout of organic scintillator and ZnS:Ag/6LiF for segmented antineutrino detectors.

    Energy Technology Data Exchange (ETDEWEB)

    Kiff, Scott D.; Reyna, David; Monahan, James (Drexel University, Philadelphia, PA); Bowden, Nathaniel S. (Lawrence Livermore National Laboratory, Livermore, CA)

    2010-10-01

    Antineutrino detection using inverse beta decay conversion has demonstrated the capability to measure nuclear reactor power and fissile material content for nuclear safeguards. Current efforts focus on aboveground deployment scenarios, for which highly efficient capture and identification of neutrons is needed to measure the anticipated antineutrino event rates in an elevated background environment. In this submission, we report on initial characterization of a new scintillation-based segmented design that uses layers of ZnS:Ag/{sup 6}LiF and an integrated readout technique to capture and identify neutrons created in the inverse beta decay reaction. Laboratory studies with multiple organic scintillator and ZnS:Ag/{sup 6}LiF configurations reliably identify {sup 6}Li neutron captures in 60 cm-long segments using pulse shape discrimination.

  1. Neutron detection and identification using ZnS:Ag/{sup 6}LiF in segmented antineutrino detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kiff, Scott D., E-mail: skiff@sandia.gov [Sandia National Laboratories, 7011 East Avenue, Livermore, CA 94550 (United States); Bowden, Nathaniel [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Lund, Jim; Reyna, David [Sandia National Laboratories, 7011 East Avenue, Livermore, CA 94550 (United States)

    2011-10-01

    Antineutrino detection using inverse beta-decay conversion has demonstrated capability to measure nuclear reactor power and fissile material content for nuclear safeguards. Current efforts focus on aboveground deployment scenarios, for which a successful background rejection strategy will be needed to measure the anticipated antineutrino event rates. In this paper, we report on initial studies to quantify the intrinsic capture efficiency and particle identification capabilities of a new scintillation-based segmented design that uses layers of ZnS:Ag/{sup 6}LiF to capture and identify neutrons created in the inverse beta-decay reaction. Laboratory efficiency measurements are consistent with MCNP5 calculations, estimating {sup 6}Li neutron conversion efficiency above 50% for practical full-scale detector configurations.

  2. Simulation of Reactors for Antineutrino Experiments Using DRAGON

    CERN Document Server

    Winslow, L

    2011-01-01

    From the discovery of the neutrino to the precision neutrino oscillation measurements in KamLAND, nuclear reactors have proven to be an important source of antineutrinos. As their power and our knowledge of neutrino physics has increased, more sensitive measurements have become possible. The next generation of reactor antineutrino experiments require more detailed simulations of the reactor core. Many of the reactor simulation codes are proprietary which makes detailed studies difficult. Here we present the results of the open source DRAGON code and compare it to other industry standards for reactor modeling. We use published data from the Takahama reactor to determine the quality of the simulations. The propagation of the uncertainty to the antineutrino flux is also discussed.

  3. A reference worldwide model for antineutrinos from reactors

    CERN Document Server

    Baldoncini, Marica; Fiorentini, Giovanni; Mantovani, Fabio; Ricci, Barbara; Strati, Virginia; Xhixha, Gerti

    2014-01-01

    Antineutrinos produced at nuclear reactors constitute a severe source of background for the detection of geoneutrinos, which bring to the Earth's surface information about natural radioactivity in the whole planet. In this framework we provide a reference worldwide model for antineutrinos from reactors, in view of reactors operational records yearly published by the International Atomic Energy Agency (IAEA). We evaluate the expected signal from commercial reactors for ongoing (KamLAND and Borexino), planned (SNO+) and proposed (Juno, RENO-50, LENA and Hanohano) experimental sites. Uncertainties related to reactor antineutrino production, propagation and detection processes are estimated using a Monte Carlo based approach, which provides an overall site dependent uncertainty on the signal in the geoneutrino energy window on the order of 3%. We also implement the off-equilibrium correction to the reference reactor spectra associated with the long-lived isotopes and we estimate a 2.4% increase of the unoscillate...

  4. Antineutrino monitoring for the Iranian heavy water reactor

    CERN Document Server

    Christensen, Eric; Jaffke, Patrick; Shea, Thomas

    2014-01-01

    In this note we discuss the potential application of antineutrino monitoring to the Iranian heavy water reactor at Arak, the IR-40, as a non-proliferation measure. We demonstrate that an above ground detector positioned right outside the IR-40 reactor building could meet and in some cases significantly exceed the verification goals identified by IAEA for plutonium production or diversion from declared inventories. In addition to monitoring the reactor during operation, observing antineutrino emissions from long-lived fission products could also allow monitoring the reactor when it is shutdown. Antineutrino monitoring could also be used to distinguish different levels of fuel enrichment. Most importantly, these capabilities would not require a complete reactor operational history and could provide a means to re-establish continuity of knowledge in safeguards conclusions should this become necessary.

  5. Towards hot electron mediated charge exchange in hyperthermal energy ion-surface interactions

    DEFF Research Database (Denmark)

    Ray, M. P.; Lake, R. E.; Thomsen, Lasse Bjørchmar;

    2010-01-01

    electrons useful for driving chemical reactions at surfaces. Using the binary collision approximation and a nonadiabatic model that takes into account the time-varying nature of the ion–surface interaction, the energy loss of the ions is reproduced. The energy loss for Na + ions incident on the devices...

  6. Charge exchange and ionisation in N$^{7+}$, N$^{6+}$, C$^{6+}$ - H($n=1, 2$) collisions studied systematically by theoretical approaches

    CERN Document Server

    Igenbergs, Katharin; Veiter, Alexander; Perneczky, Lukas; Frühwirth, Edwin; Wallerberger, Markus; Olson, Ronald E; Aumayr, Friedrich

    2011-01-01

    The introduction of gases like nitrogen or neon for cooling the edge region of magnetically confined fusion plasmas has triggered a renewed interest in state selective cross sections necessary for plasma diagnostics by means of charge exchange recombination spectroscopy. To improve the quality of spectroscopic data analysis, charge exchange and ionisation cross sections for N$^{7+}$ + H($n=1,2$) have been calculated using two different theoretical approaches, namely the atomic-orbital close-coupling method and the classical trajectory Monte Carlo method. Total and state resolved charge exchange cross sections are analysed in detail. In the second part, we compare two collision systems involving equally charged ions, C$^{6+}$ and N$^{6+}$ on atomic hydrogen. The analysis of the data lead to the conclusion that deviations between these two impurity ions are practically negligible. This finding is very helpful when calculating cross sections for collision systems with heavier not completely stripped impurity ion...

  7. A novel scenario for the possible X-ray line feature at ~3.5 keV: Charge exchange with bare sulfur ions

    CERN Document Server

    Gu, L; Raassen, A J J; Mullen, P D; Cumbee, R S; Lyons, D; Stancil, P C

    2015-01-01

    Motivated by recent claims of a compelling ~3.5 keV emission line from nearby galaxies and galaxy clusters, we investigate a novel plasma model incorporating a charge exchange component obtained from theoretical scattering calculations. Fitting this kind of component with a standard thermal model yields positive residuals around 3.5 keV, produced mostly by S XVI transitions from principal quantum numbers n > 8 to the ground. Such high-n states can only be populated by the charge exchange process. In this scenario, the observed 3.5 keV line flux in clusters can be naturally explained by an interaction in an effective volume of ~1 kpc^3 between a ~3 keV temperature plasma and cold dense clouds moving at a few hundred km/s. The S XVI lines at ~3.5 keV also provide a unique diagnostic of the charge exchange phenomenon in hot cosmic plasmas.

  8. Charge exchange in H{sup +} grazing scattering off clean and AlF{sub 3} covered Al(111) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lugo, J.O.; Sanchez, E.A.; Grizzi, O. [Centro Atomico Bariloche - CNEA, CONICET, Instituto Balseiro - UNC, 8400 S.C. de Bariloche, Rio Negro (Argentina); Goldberg, E.C. [INTEC (CONICET-UNL), Gueemes 3450, cc 912, 3000 Santa Fe (Argentina); Facultad de Ingenieria Quimica, Univ. Nacional del Litoral, Santiago del Estero 2829, 3000 Santa Fe (Argentina)

    2004-08-01

    Ion Scattering Spectroscopy with Time-of-Flight analysis is used to characterize the deposition of thin insulating films (AlF{sub 3}) on Al(111) samples, and to measure the ion fractions for 20 keV H{sup +} projectiles scattered off clean and AlF{sub 3} covered Al(111) surfaces. The ion fraction measured for the clean surface is {proportional_to}12%, composed mainly of negative ions. For {proportional_to}2 ML of AlF{sub 3}, the ion fraction increases, being in this case mainly composed of positive ions ({gamma}{sup +}= 33%, {gamma}{sup -}= 3%). A calculation of the dynamical evolution of the collision and the resonant charge exchange processes describes the experimental trends. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Localization of the large-angle foil-scattering beam loss caused by the multiturn charge-exchange injection

    Science.gov (United States)

    Kato, Shinichi; Yamamoto, Kazami; Yoshimoto, Masahiro; Harada, Hiroyuki; Kinsho, Michikazu

    2013-07-01

    In the 3 GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex, significant losses were observed at the branching of the H0 dump line and the beam position monitor that was inserted downstream of the H0 dump branch duct. These losses were caused by the large-angle scattering of the injection and circulating beams at the charge-exchange foil. To realize high-power operation, these losses must be mitigated. Therefore, a new collimation system was developed and installed in October 2011. To efficiently optimize this system, the behavior of particles scattered by the foil and produced by the absorber were simulated, and the optimal position and angle of the absorber were investigated. During this process, an angle regulation method for the absorber was devised. An outline of this system, the angle regulation method for the absorber, and the performance of this new collimation system are described.

  10. Self-consistent continuum random-phase approximation with finite-range interactions for charge-exchange excitations

    CERN Document Server

    De Donno, V; Anguiano, M; Lallena, A M

    2016-01-01

    The formalism of the continuum random-phase approximation theory which treats, without ap- proximations, the continuum part of the single-particle spectrum, is extended to describe charge- exchange excitations. Our approach is self-consistent, meaning that we use a unique, finite-range, interaction in the Hartree-Fock calculations which generate the single-particle basis and in the con- tinuum random-phase approximation which describes the excitation. We study excitations induced by the Fermi, Gamow-Teller and spin-dipole operators in doubly magic nuclei by using four Gogny- like finite-range interactions, two of them containing tensor forces. We focus our attention on the importance of the correct treatment of the continuum configuration space and on the effects of the tensor terms of the force.1

  11. Charge Exchange in Low-Energy H, D + C4+ Collisions with Full Account of Electron Translation

    Directory of Open Access Journals (Sweden)

    N. Vaeck

    2002-03-01

    Full Text Available We report the application of the quantum approach, which takes full account of electron translation at low collisional energies, to the charge exchange process H, D + C4+ → H+, D+ + C3+(3s; 3p; 3d. The partial and the total integral cross sections of the process are calculated in the energy range from 1 till 60 eV/amu. It is shown that the present results are independent from the upper integration limit for numerical solution of the coupled channel equations although nonadiabatic couplings remain nonzero up to infinity. The calculated partial and total cross sections are in agreement with the previous low-energy calculations and the available experimental data. It is shown that for low collisional energies the isotopic effect takes place. The observed effect is explained in terms of the nonadiabatic dynamics.

  12. The role of multiple electron capture in the x-ray emission process following charge exchange collisions with neutral targets

    International Nuclear Information System (INIS)

    In this work we theoretically study photonic spectra that follow charge exchange processes between highly charged ions and neutral argon and CO targets. The range of collision energies studied is 5 eV/amu-10 keV/amu, covering typical EBIT-traps and Solar Wind energies. Our studies are based on multiple electrons schemes within the classical trajectory Monte Carlo method. Electrons are sorted with the sequential binding energies for the target under consideration. The role played by the multiple electron capture process for the different collision systems under consideration is explicitly analyzed and its contribution separated as arising from double radiative decay and autoionizing multiple capture. Present studies are stimulated by the upcoming launch of the Astro-H mission in 2015, which will provide high resolution spectra in the 0.3 keV-12keV band

  13. Charge exchange between H(1s) and fully stripped heavy ions at low-keV impact energies

    International Nuclear Information System (INIS)

    Approximate cross sections for charge transfer between ground-state atomic hydrogen and completely stripped ions of C, N, O, Ne, Si, and Ar have been obtained in the velocity range 6 x 106--7 x 107 cm/sec. In these collisions, electron capture occurs predominantly into high-lying orbitals of the product heavy ion. The calculations are made using the Landau-Zener theory modified for application to a multistate system. The peak cross sections are found to increase by about a factor of 5 in going from C+6 ( approx. = 21 A2) to Ar+18 ( approx. = 110 A2) and the cross-section curves tend to ''flatten out'' for the heavier ions where three or four crossings contribute to the charge exchange. At the higher energies, the cross sections become roughly equal to 1.4 x 10-16Z3/2 cm2

  14. A microscopic approach based on particle-vibration coupling: application to charge-exchange transitions and multiplets in odd nuclei

    Directory of Open Access Journals (Sweden)

    Colò Gianluca

    2016-01-01

    Full Text Available In this contribution, we shall describe a formalism that goes beyond the simple time-dependent mean field and is based on particle-vibration coupling (PVC. Such a formalism has been developed with the idea of being self-consistent. It makes use of Skyrme effective forces, and has been used for several applications. We will focus on charge-exchange transitions, namely we will show that our model describes well both the Gamow-Teller giant resonance width, and the low-lying transitions associated with β-decay. In this latter case, including PVC produces a significant improvement of the half-lives obtained at mean-field level, and leads to a good agreement with experimental data. We will end by discussing particle-phonon multiplets in odd nuclei.

  15. Antineutrino flux from the Laguna Verde Nuclear Power Plant

    CERN Document Server

    Chavez-Estrada, Marisol

    2015-01-01

    We present a a calculation of the antineutrino flux produced by the reactors at the Laguna Verde Nuclear Power Plant in M\\'exico, based on the antineutrino spectra produced in the decay chains of the fission fragments of the main isotopes in the reactor core, and their fission rates, that have been calculated using the DRAGON simulation code. We also present an estimate of the number of expected events in a detector made of plastic scintillator with a mass of 1 ton, at 100 m from the reactor cores.

  16. Antineutrino Flux from the Laguna Verde Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    Marisol Chavez-Estrada

    2015-01-01

    Full Text Available We present a calculation of the antineutrino flux produced by the reactors at the Laguna Verde Nuclear Power Plant in México, based on the antineutrino spectra produced in the decay chains of the fission fragments of the main isotopes in the reactor core, and their fission rates, which have been calculated using the DRAGON simulation code. We also present an estimate of the number of expected events in a detector made of plastic scintillator with a mass of 1 ton, at 100 m from the reactor cores.

  17. Spectral structure of electron antineutrinos from nuclear reactors.

    Science.gov (United States)

    Dwyer, D A; Langford, T J

    2015-01-01

    Recent measurements of the positron energy spectrum obtained from inverse beta decay interactions of reactor electron antineutrinos show an excess in the 4 to 6 MeV region relative to current predictions. First-principles calculations of fission and beta decay processes within a typical pressurized water reactor core identify prominent fission daughter isotopes as a possible origin for this excess. These calculations also predict percent-level substructures in the antineutrino spectrum due to Coulomb effects in beta decay. Precise measurement of these substructures can elucidate the nuclear processes occurring within reactors. These substructures can be a systematic issue for measurements utilizing the detailed spectral shape.

  18. Spectral Structure of Electron Antineutrinos from Nuclear Reactors

    CERN Document Server

    Dwyer, D A

    2014-01-01

    Recent measurements of the positron energy spectrum obtained from inverse beta decay interactions of reactor electron antineutrinos show an excess in the 4 to 6 MeV region relative to current predictions. First-principle calculations of fission and beta decay processes within a typical pressurized water reactor core identify prominent fission daughter isotopes as a possible origin for this excess. These calculations also predict percent-level substructure in the antineutrino spectrum due to Coulomb effects in beta decay. Precise measurement of this substructure can constrain nuclear reactor physics. The substructure can be a systematic uncertainty for measurements utilizing the detailed spectral shape.

  19. Geophysics with Hawaiian Anti-neutrino Observatory (Hanohano)

    Energy Technology Data Exchange (ETDEWEB)

    Maricic, J., E-mail: jelena.maricic@physics.drexel.edu [Drexel University, Philadelphia, PA, 19104, University of Hawaii, Honolulu, HI, 96822 (United States)

    2011-12-15

    The design studies are under way for the deep ocean anti-neutrino observatory located in the vicinity of the Big Island (Hawaii) with the main goal of measuring geo-neutrino flux from the mantle and core which can exclusively be done in a location far from the continental plates such is Hawaiian Islands chain. Hanohano will also accomplish the definitive measurement of the electron anti-neutrino signal from the core to observe or eliminate a hypothetical natural reactor in the Earth's core.

  20. Geophysics with Hawaiian Anti-neutrino Observatory (Hanohano)

    Science.gov (United States)

    Maricic, J.; Hanohano Collaboration

    2011-12-01

    The design studies are under way for the deep ocean anti-neutrino observatory located in the vicinity of the Big Island (Hawaii) with the main goal of measuring geo-neutrino flux from the mantle and core which can exclusively be done in a location far from the continental plates such is Hawaiian Islands chain. Hanohano will also accomplish the definitive measurement of the electron anti-neutrino signal from the core to observe or eliminate a hypothetical natural reactor in the Earth's core.

  1. Reactor Simulation for Antineutrino Experiments using DRAGON and MURE

    CERN Document Server

    Jones, C L; Conrad, J M; Djurcic, Z; Fallot, M; Giot, L; Keefer, G; Onillon, A; Winslow, L

    2011-01-01

    Rising interest in nuclear reactors as a source of antineutrinos for experiments motivates validated, fast, and accessible simulations to predict reactor fission rates. Here we present results from the DRAGON and MURE simulation codes and compare them to other industry standards for reactor core modeling. We use published data from the Takahama-3 reactor to evaluate the quality of these simulations against the independently measured fuel isotopic composition. The propagation of the uncertainty in the reactor operating parameters to the resulting antineutrino flux predictions is also discussed.

  2. Is there a high-y anomaly in antineutrino interactions

    International Nuclear Information System (INIS)

    We have analyzed data taken in the CERN narrow-band neutrino and antineutrino beams with regard to the ''high-y anomaly'' observed by previous experiments at Fermilab. At neutrino energies between 30 and 200 GeV, the anti ν and ν charged-current cross-section ratios and muon-inelasticity distributions disagree with the earlier results. In particular, there is no evidence for energy-dependent effects in the antineutrino data which constitute an important aspect of the alleged anomaly

  3. Antineutrino Flux from the Laguna Verde Nuclear Power Plant

    OpenAIRE

    Marisol Chavez-Estrada; Aguilar-Arevalo, Alexis A.

    2015-01-01

    We present a calculation of the antineutrino flux produced by the reactors at the Laguna Verde Nuclear Power Plant in M\\'exico, based on the antineutrino spectra produced in the decay chains of the fission fragments of the main isotopes in the reactor core, and their fission rates, that have been calculated using the DRAGON simulation code. We also present an estimate of the number of expected events in a detector made of plastic scintillator with a mass of 1 ton, at 100 m from the reactor co...

  4. Investigation of Large LGB Detectors for Antineutrino Detection

    CERN Document Server

    Nelson, P

    2011-01-01

    A detector material or configuration that can provide an unambiguous indication of neutron capture can substantially reduce random coincidence backgrounds in antineutrino detection and capture-gated neutron spectrometry applications. Here we investigate the performance of such a material, a composite of plastic scintillator and $^6$Li$_6^{nat}$Gd$(^{10}$BO$_{3})_{3}$:Ce (LGB) crystal shards of ~1 mm dimension and comprising 1% of the detector by mass. While it is found that the optical propagation properties of this material as currently fabricated are only marginally acceptable for antineutrino detection, its neutron capture identification ability is encouraging.

  5. Investigation of large LGB detectors for antineutrino detection

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, P. [Department of Physics, Naval Postgraduate School, Monterey, CA 93943 (United States); Bowden, N.S., E-mail: nbowden@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2011-12-21

    A detector material or configuration that can provide an unambiguous indication of neutron capture can substantially reduce random coincidence backgrounds in antineutrino detection and capture-gated neutron spectrometry applications. Here we investigate the performance of such a material, a composite of plastic scintillator and {sup 6}Li{sub 6}{sup nat}Gd({sup 10}BO{sub 3}){sub 3}:Ce (LGB) crystal shards of Almost-Equal-To 1 mm dimension and comprising 1% of the detector by mass. While it is found that the optical propagation properties of this material as currently fabricated are only marginally acceptable for antineutrino detection, its neutron capture identification ability is encouraging.

  6. Optimization and application of cooled avalanche photodiodes for spectroscopic fluctuation measurements with ultra-fast charge exchange recombination spectroscopy

    Science.gov (United States)

    Truong, D. D.; Fonck, R. J.; McKee, G. R.

    2016-11-01

    The Ultra-Fast Charge Exchange Recombination Spectroscopy (UF-CHERS) diagnostic is a highly specialized spectroscopic instrument with 2 spatial channels consisting of 8 spectral channels each and a resolution of ˜0.25 nm deployed at DIII-D to measure turbulent ion temperature fluctuations. Charge exchange emissions are obtained between 528 and 530 nm with 1 μs time resolution to study plasma instabilities. A primary challenge of extracting fluctuation measurements from raw UF-CHERS signals is photon and electronic noise. In order to reduce dark current, the Avalanche Photodiode (APD) detectors are thermo-electrically cooled. State-of-the-art components are used for the signal amplifiers and conditioners to minimize electronic noise. Due to the low incident photon power (≤1 nW), APDs with a gain of up to 300 are used to optimize the signal to noise ratio. Maximizing the APDs' gain while minimizing the excess noise factor (ENF) is essential since the total noise of the diagnostic sets a floor for the minimum level of detectable broadband fluctuations. The APDs' gain should be high enough that photon noise dominates electronic noise, but not excessive so that the ENF overwhelms plasma fluctuations. A new generation of cooled APDs and optimized preamplifiers exhibits significantly enhanced signal-to-noise compared to a previous generation. Experiments at DIII-D have allowed for characterization and optimization of the ENF vs. gain. A gain of ˜100 at 1700 V is found to be near optimal for most plasma conditions. Ion temperature and toroidal velocity fluctuations due to the edge harmonic oscillation in quiescent H-mode plasmas are presented to demonstrate UF-CHERS' capabilities.

  7. A study of quasi-elastic muon neutrino and antineutrino scattering in the NOMAD experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lyubushkin, V.; Bunyatov, S.; Chukanov, A.; Klimov, O.; Kustov, D.; Nefedov, Yu.; Samoylov, O.; Tereshchenko, V. [JINR, Dubna (Russian Federation); Popov, B. [JINR, Dubna (Russian Federation); LPNHE, Univ. of Paris VI and VII, Paris (France); Kim, J.J.; Godley, A.; Ling, J.; Mishra, S.R.; Petti, R.; Seaton, M.; Wu, Q. [Univ. of South Carolina, Columbia, SC (United States); Camilleri, L.; Autiero, D.; Di Lella, L.; Couto e Silva, E. do; Ferrere, D.; Grant, A.; Kokkonen, J.; Linssen, L.; Placci, A.; Stiegler, U.; Tsesmelis, E.; Vidal-Sitjes, G.; Wilson, F.F. [CERN, Geneva (Switzerland); Levy, J.M.; Astier, P.; Banner, M.; Dumarchez, J.; Lachaud, C.; Letessier-Selvon, A.; Schahmaneche, K.; Touchard, A.M.; Vannucci, F. [LPNHE, Univ. of Paris VI and VII, Paris (France); Mezzetto, M.; Baldo-Ceolin, M.; Bobisut, F.; Collazuol, G.; Contalbrigo, M.; Gibin, D.; Guglielmi, A.; Lacaprara, S.; Laveder, M.; Rebuffi, L.; Sconza, A.; Zuccon, P. [Univ. of Padova (Italy); INFN, Padova (Italy); Naumov, D. [JINR, Dubna (Russian Federation); Univ. of Florence (Italy); INFN, Florence (Italy); Alekhin, S. [Inst. for High Energy Physics, Protvino, Moscow Region (Russian Federation); Baldisseri, A.; Besson, N.; Bouchez, J.; Gosset, J.; Hagner, C.; Mechain, X.; Meyer, J.P.; Stolarczyk, T.; Zaccone, H. [DAPNIA, Saclay (France); Bassompierre, G.; Gaillard, J.M.; Gouanere, M.; Mendiburu, J.P.; Nedelec, P.; Pessard, H.; Sillou, D. [LAPP, Annecy (France); Benslama, K.; Degaudenzi, H.; Joseph, C.; Juget, F.; Nguyen-Mau, C.; Sozzi, G.; Tareb-Reyes, M.; Tran, M.T.; Vacavant, L.; Vieira, J.M. [Univ. of Lausanne, Lausanne (Switzerland); Bird, I. [CERN, Geneva (Switzerland); Univ. of Lausanne (Switzerland); Blumenfeld, B.; Long, J. [Johns Hopkins Univ., Baltimore, MD (United States); Boyd, S.; Ellis, M.; Peak, L.S.; Ulrichs, J.; Varvell, K.E.; Yabsley, B.D. [Univ. of Sydney (Australia); Bueno, A. [Harvard Univ., Cambridge, MA (United States); ETH Zurich (Switzerland)] [and others

    2009-10-15

    We have studied the muon neutrino and antineutrino quasi-elastic (QEL) scattering reactions ({nu}{sub {mu}}n {yields}{mu}{sup -}p and anti {nu}{sub {mu}}p{yields}{mu}{sup +}n) using a set of experimental data collected by the NOMAD Collaboration. We have performed measurements of the cross-section of these processes on a nuclear target (mainly carbon) normalizing it to the total {nu}{sub {mu}}(anti {nu}{sub {mu}}) charged-current cross section. The results for the flux-averaged QEL cross sections in the (anti)neutrino energy interval 3-100 GeV are left angle {sigma}{sub qel} right angle {sub {nu}}{sub {mu}}=(0.92{+-}0.02(stat){+-}0.06(syst)) x 10{sup -38} cm{sup 2} and left angle {sigma}{sub qel} right angle {sub anti} {sub {nu}{sub {mu}}}{sub =}(0.81{+-}0.05(stat){+-}0.09(syst)) x 10{sup -38} cm{sup 2} for neutrino and antineutrino, respectively. The axial mass parameter M{sub A} was extracted from the measured quasi-elastic neutrino cross section. The corresponding result is M{sub A}=1.05{+-}0.02(stat){+-}0.06(syst) GeV. It is consistent with the axial mass values recalculated from the antineutrino cross section and extracted from the pure Q{sup 2} shape analysis of the high purity sample of {nu}{sub {mu}} quasi-elastic 2-track events, but has smaller systematic error and should be quoted as the main result of this work. Our measured M{sub A} is found to be in good agreement with the world average value obtained in previous deuterium filled bubble chamber experiments. The NOMAD measurement of M{sub A} is lower than those recently published by K2K and MiniBooNE Collaborations. However, within the large errors quoted by these experiments on M{sub A}, these results are compatible with the more precise NOMAD value. (orig.)

  8. On the polarization effects in (p,n) reactions between the A=48 isobarical states

    OpenAIRE

    Isakov, V. I.

    2002-01-01

    Isotopical dependence of spin-orbit splitting discovered by us in spectra of heavy nuclei close to doubly magic ones is checked in polarization effects arising in charge exchange (p,n) reaction between the A=48 isobarical states.

  9. Neutron Capture and the Antineutrino Yield from Nuclear Reactors.

    Science.gov (United States)

    Huber, Patrick; Jaffke, Patrick

    2016-03-25

    We identify a new, flux-dependent correction to the antineutrino spectrum as produced in nuclear reactors. The abundance of certain nuclides, whose decay chains produce antineutrinos above the threshold for inverse beta decay, has a nonlinear dependence on the neutron flux, unlike the vast majority of antineutrino producing nuclides, whose decay rate is directly related to the fission rate. We have identified four of these so-called nonlinear nuclides and determined that they result in an antineutrino excess at low energies below 3.2 MeV, dependent on the reactor thermal neutron flux. We develop an analytic model for the size of the correction and compare it to the results of detailed reactor simulations for various real existing reactors, spanning 3 orders of magnitude in neutron flux. In a typical pressurized water reactor the resulting correction can reach ∼0.9% of the low energy flux which is comparable in size to other, known low-energy corrections from spent nuclear fuel and the nonequilibrium correction. For naval reactors the nonlinear correction may reach the 5% level by the end of cycle.

  10. Electron Neutrino and Antineutrino Appearance in the MINOS Detector

    Energy Technology Data Exchange (ETDEWEB)

    Schreckenberger, Adam Paul [Univ. of Minnesota, Minneapolis, MN (United States)

    2013-04-01

    The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline neutrino experiment that utilizes a particle beam and two steel-scintillator calorimeters designed to determine the parameters associated with muon neutrino disappearance. Analysis methods developed by the MINOS νe group have facilitated the placement of limits upon the mixing angle associated with νμ → νe oscillations. Since the polarity of the focusing horns can be switched, we can perform a similar analysis with an antineutrino-enriched beam to select electron antineutrino appearance candidates. Using 3.34e20 POT (protons on target) in the antineutrino mode, we exclude θ13 = 0 at the 80% C.L. A joint fit of the 3.34e20 POT antineutrino and 10.6e20 POT neutrino samples excluded θ13 = 0 at the 96% C.L. In addition, the combined data were used to produce exclusions regarding the CP-violating phase.

  11. Neutron capture and the antineutrino yield from nuclear reactors

    CERN Document Server

    Huber, Patrick

    2015-01-01

    We identify a new, flux-dependent correction to the antineutrino spectrum as produced in nuclear reactors. The abundance of certain nuclides, whose decay chains produce antineutrinos above the threshold for inverse beta decay, has a nonlinear dependence on the neutron flux, unlike the vast majority of antineutrino producing nuclides, whose decay rate is directly related to the fission rate. We have identified four of these so-called nonlinear nuclides and determined that they result in an antineutrino excess at low-energies below 3.2MeV, dependent on the reactor thermal neutron flux. We develop an analytic model for the size of the correction and compare it to the results of detailed reactor simulations for various real existing reactors, spanning 3 orders of magnitude in neutron flux. In a typical pressurized water reactor the resulting correction can reach 0.9% of the low energy flux which is comparable in size to other, known low-energy corrections from spent nuclear fuel and the non-equilibrium correction...

  12. Neutron Capture and the Antineutrino Yield from Nuclear Reactors

    Science.gov (United States)

    Huber, Patrick; Jaffke, Patrick

    2016-03-01

    We identify a new, flux-dependent correction to the antineutrino spectrum as produced in nuclear reactors. The abundance of certain nuclides, whose decay chains produce antineutrinos above the threshold for inverse beta decay, has a nonlinear dependence on the neutron flux, unlike the vast majority of antineutrino producing nuclides, whose decay rate is directly related to the fission rate. We have identified four of these so-called nonlinear nuclides and determined that they result in an antineutrino excess at low energies below 3.2 MeV, dependent on the reactor thermal neutron flux. We develop an analytic model for the size of the correction and compare it to the results of detailed reactor simulations for various real existing reactors, spanning 3 orders of magnitude in neutron flux. In a typical pressurized water reactor the resulting correction can reach ˜0.9 % of the low energy flux which is comparable in size to other, known low-energy corrections from spent nuclear fuel and the nonequilibrium correction. For naval reactors the nonlinear correction may reach the 5% level by the end of cycle.

  13. Monitoring Akkuyu Nuclear Reactor Using Anti-Neutrino Flux Measurement

    CERN Document Server

    Ozturk, Sertac; Ozcan, V Erkcan; Unel, Gokhan

    2016-01-01

    We present a simulation based study for monitoring Akkuyu Nuclear Power Plant's activity using anti-neutrino flux originating from the reactor core. A water Cherenkov detector has been designed and optimization studies have been performed using Geant4 simulation toolkit. A first study for the design of a monitoring detector facility for Akkuyu Nuclear Power Plant has been discussed in this paper.

  14. Charge exchange transition probability for collisions between unlike ions and atoms within the adiabatic approximation

    Science.gov (United States)

    Xu, Y. J.; Khandelwal, G. S.; Wilson, John W.

    1989-01-01

    A simple formula for the transition probability for electron exchange between unlike ions and atoms is established within the adiabatic approximation by employing the Linear Combination of Atomic Orbitals (LCAO) method. The formula also involves an adiabatic parameter, introduced by Massey, and thus the difficulties arising from the internal energy defect and the adiabatic approximation are avoided. Specific reactions Li(+++) + H to Li(++) + H(+) and Be(4+) + H to Be(3+) + H(+) are considered as examples. The calculated capture cross section results of the present work are compared with the experimental data and with the calculation of other authors over the velocity range of 10(7) cm/sec to 10(8) cm/sec.

  15. Measuring Antineutrino Oscillations with the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Justin John [Univ. of Oxford (United Kingdom)

    2008-09-01

    MINOS is a long baseline neutrino oscillation experiment. A manmade beam of predominantly muon neutrinos is detected both 1 km and 735 km from the production point by two functionally identical detectors. A comparison of the energy spectra measured by the two detectors shows the energy-dependent disappearance of muon neutrinos characteristic of oscillations and allows a measurement of the parameters governing the oscillations. This thesis presents work leading to measurements of disappearance in the 6% $\\bar{v}$μ background in that beam. A calibration is developed to correct for time-dependent changes in the responses of both detectors, reducing the corresponding uncertainty on hadronic energy measurements from 1.8% to 0.4% in the near detector and from 0.8% to 0.4% in the far detector. A method of selecting charged current $\\bar{v}$μ events is developed, with purities (efficiencies) of 96.5% (74.4%) at the near detector, and 98.8% (70.9%) at the far detector in the region below 10 GeV reconstructed antineutrino energy. A method of using the measured near detector neutrino energy spectrum to predict that expected at the far detector is discussed, and developed for use in the $\\bar{v}$μ analysis. Sources of systematic uncertainty contributing to the oscillation measurements are discussed. In the far detector, 32 charged current $\\bar{v}$μ events are observed below a reconstructed energy of 30 GeV, compared to an expectation of 47.8 for Δ$\\bar{m}$atm2 = Δ$\\bar{m}$atm2, sin2(2$\\bar{θ}$23) = sin2(2θ23). This deficit, in such a low-statistics sample, makes the result difficult to interpret in the context of an oscillation parameter measurement. Possible sources for the discrepancy are discussed, concluding that considerably more data are required for a definitive solution. Running MINOS with a dedicated $\\bar

  16. Chandra observations of comet 2P/Encke 2003 : First detection of a collisionally thin, fast solar wind charge exchange system

    NARCIS (Netherlands)

    Lisse, CM; Christian, DJ; Dennerl, K; Wolk, SJ; Bodewits, D; Hoekstra, R; Combi, MR; Makinen, T; Dryer, M; Fry, CD; Weaver, H

    2005-01-01

    We report the results of 15 hr of Chandra observations of comet 2P/Encke 2003 on November 24. X-ray emission from comet Encke was resolved on scales of 500-40,000 km, with unusual morphology due to the presence of a low-density, collisionally thin (to charge exchange) coma. A light curve with peak-t

  17. Four-body corrected first Born approximation for single charge exchange at high impact energies

    Science.gov (United States)

    Mančev, Ivan

    1995-06-01

    Single electron capture is investigated by means of the four-body boundary corrected first Born approximation (CB1-4B). The "post" form of the transition amplitude for a general heteronuclear case (Zp; e1) + (ZT; e2) → (Zp; e1, e2) + ZT is derived in the form of readily obtainable two-dimensional real integrals. We investigate the sensitivity of the total cross sections to the choice of ground state wave function for helium-like atoms. Also, the influence of non-captured electron on the final results is studied. As an illustration, the CB1-4B method is used to compute the total cross sections for reactions: H(1s) + H(1s) → H-(1s2) + H+, He+(1s) + H(1s) → He(1s2) + H+ and He+(1s) + He+(1s) → He(1s2) + α. The theoretical cross sections are found to be in good agreement with the available experimental data.

  18. Measurement of charge exchange cross sections for highly charged xenon and thorium ions with molecular hydrogen in a Penning Ion Trap

    Energy Technology Data Exchange (ETDEWEB)

    Weinberg, G.M.

    1995-12-01

    Highly charged xenon (35+ to 46+) and thorium (72+ to 79+) ions were produced in an Electron Beam Ion Trap (EBIT). The ions were extracted from EBIT in a short pulse. Ions of one charge state were selected using an electromagnet. The ions were recaptured at low energy in a cryogenic Penning trap (RETRAP). As the ions captured electrons from molecular hydrogen, populations of the various charge states were obtained by measuring the image currents induced by the ions on the electrodes of the trap. Data on the number of ions in each charge state vs. time were compared to theoretical rate equations in order to determine the average charge exchange rates. These rates were compared to charge exchange rates of an ion with a known charge exchange cross section (Ar{sup 11+}) measured in a similar manner in order to determine the average charge exchange cross sections for the highly charged ions. The energy of interaction between the highly charged ions and hydrogen was estimated to be 4 eV in the center of mass frame. The mean charge exchange cross sections were 9 {times} 10{sup {minus}14} cm{sup 2} for Xe{sup 43+} to Xe{sup 46+} and 2 {times} 10{sup {minus}13} cm{sup 2} for Th{sup 73+} to Th{sup 79+}. Double capture was approximately 20--25% of the total for both xenon and thorium. A fit indicated that the cross sections were approximately proportional to q. This is consistent with a linear dependence of cross section on q within the measurement uncertainties.

  19. I. Charge exchange collisions of highly stripped ions with atomic hydrogen. II. Development of a three-stage double tandem accelerator-decelerator system for low energy, highly stripped ions. Final report, March 1, 1977-May 30, 1981

    International Nuclear Information System (INIS)

    The first measurements of charge exchange (electron transfer) in kiloelectron-volt-energy highly stripped boron, carbon, nitrogen and oxygen ion collisions with atoms have been extended to additional collision energies and charge values for the ions. A first accelerator-decelerator source of very highly stripped ions has been developed, and its usefulness in charge exchange studies established

  20. Modeling the magnetospheric X-ray emission from solar wind charge exchange with verification from XMM-Newton observations

    Science.gov (United States)

    Whittaker, Ian C.; Sembay, Steve; Carter, Jennifer A.; Read, Andrew M.; Milan, Steve E.; Palmroth, Minna

    2016-05-01

    An MHD-based model of terrestrial solar wind charge exchange (SWCX) is created and compared to 19 case study observations in the 0.5-0.7 keV emission band taken from the European Photon Imaging Cameras on board XMM-Newton. This model incorporates the Global Unified Magnetosphere-Ionosphere Coupling Simulation-4 MHD code and produces an X-ray emission datacube from O7+ and O8+ emission lines around the Earth using in situ solar wind parameters as the model input. This study details the modeling process and shows that fixing the oxygen abundances to a constant value reduces the variance when comparing to the observations, at the cost of a small accuracy decrease in some cases. Using the ACE oxygen data returns a wide ranging accuracy, providing excellent correlation in a few cases and poor/anticorrelation in others. The sources of error for any user wishing to simulate terrestrial SWCX using an MHD model are described here and include mask position, hydrogen to oxygen ratio in the solar wind, and charge state abundances. A dawn-dusk asymmetry is also found, similar to the results of empirical modeling. Using constant oxygen parameters, magnitudes approximately double that of the observed count rates are returned. A high accuracy is determined between the model and observations when comparing the count rate difference between enhanced SWCX and quiescent periods.

  1. A combined desorption ionization by charge exchange (DICE) and desorption electrospray ionization (DESI) source for mass spectrometry.

    Science.gov (United States)

    Chan, Chang-Ching; Bolgar, Mark S; Miller, Scott A; Attygalle, Athula B

    2011-01-01

    A source that couples the desorption ionization by charge exchange (DICE) and desorption electrospray ionization (DESI) techniques together was demonstrated to broaden the range of compounds that can be analyzed in a single mass spectrometric experiment under ambient conditions. A tee union was used to mix the spray reagents into a partially immiscible blend before this mixture was passed through a conventional electrospray (ES) probe capillary. Using this technique, compounds that are ionized more efficiently by the DICE method and those that are ionized better with the DESI procedure could be analyzed simultaneously. For example, hydroquinone, which is not detected when subjected to DESI-MS in the positive-ion generation mode, or the sodium adduct of guaifenesin, which is not detected when examined by DICE-MS, could both be detected in one experiment when the two techniques were combined. The combined technique was able to generate the molecular ion, proton and metal adduct from the same compound. When coupled to a tandem mass spectrometer, the combined source enabled the generation of product ion spectra from the molecular ion and the [M + H](+) or [M + metal](+) ions of the same compound without the need to physically change the source from DICE to DESI. The ability to record CID spectra of both the molecular ion and adduct ions in a single mass spectrometric experiment adds a new dimension to the array of mass spectrometric methods available for structural studies. PMID:21472555

  2. A Combined Desorption Ionization by Charge Exchange (DICE) and Desorption Electrospray Ionization (DESI) Source for Mass Spectrometry

    Science.gov (United States)

    Chan, Chang-Ching; Bolgar, Mark S.; Miller, Scott A.; Attygalle, Athula B.

    2011-01-01

    A source that couples the desorption ionization by charge exchange (DICE) and desorption electrospray ionization (DESI) techniques together was demonstrated to broaden the range of compounds that can be analyzed in a single mass spectrometric experiment under ambient conditions. A tee union was used to mix the spray reagents into a partially immiscible blend before this mixture was passed through a conventional electrospray (ES) probe capillary. Using this technique, compounds that are ionized more efficiently by the DICE method and those that are ionized better with the DESI procedure could be analyzed simultaneously. For example, hydroquinone, which is not detected when subjected to DESI-MS in the positive-ion generation mode, or the sodium adduct of guaifenesin, which is not detected when examined by DICE-MS, could both be detected in one experiment when the two techniques were combined. The combined technique was able to generate the molecular ion, proton and metal adduct from the same compound. When coupled to a tandem mass spectrometer, the combined source enabled the generation of product ion spectra from the molecular ion and the [M + H]+ or [M + metal]+ ions of the same compound without the need to physically change the source from DICE to DESI. The ability to record CID spectra of both the molecular ion and adduct ions in a single mass spectrometric experiment adds a new dimension to the array of mass spectrometric methods available for structural studies.

  3. Charge state distributions and charge exchange cross sections of carbon in helium at 30-258 keV

    Science.gov (United States)

    Maxeiner, Sascha; Seiler, Martin; Suter, Martin; Synal, Hans-Arno

    2015-10-01

    With the introduction of helium stripping in radiocarbon (14C) accelerator mass spectrometry (AMS), higher +1 charge state yields in the 200 keV region and fewer beam losses are observed compared to nitrogen or argon stripping. To investigate the feasibility of even lower beam energies for 14C analyses the stripping characteristics of carbon in helium need to be further studied. Using two different AMS systems at ETH Zurich (myCADAS and MICADAS), ion beam transmissions of carbon ions for the charge states -1, +1, +2 and +3 were measured in the range of 258 keV down to 30 keV. The correction for beam losses and the extraction of charge state yields and charge exchange cross sections will be presented. An increase in population of the +1 charge state towards the lowest measured energies up to 75% was found as well as agreement with previous data from literature. The findings suggest that more compact radiocarbon AMS systems are possible and could provide even higher efficiency than current systems operating in the 200 keV range.

  4. Overview on R and D and design activities for the ITER core charge exchange spectroscopy diagnostic system

    Energy Technology Data Exchange (ETDEWEB)

    Biel, W., E-mail: w.biel@fz-juelich.de [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Baross, T. [KFKI RMKI, EURATOM Association, PO Box 49, H-1521 Budapest (Hungary); Bourauel, P. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Dunai, D. [KFKI RMKI, EURATOM Association, PO Box 49, H-1521 Budapest (Hungary); Durkut, M. [TNO Science and Industry, Partner in ITER-NL, P.O. Box 155, 2600 AD Delft (Netherlands); Erdei, G. [BME, EURATOM Association, PO Box 91, H-1521 Budapest (Hungary); Hawkes, N. [Association EURATOM/CCFE, OX14 3DB Abingdon (United Kingdom); Hellermann, M. von [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, partner in the Trilateral Euregio Cluster and ITER-NL, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Hogenbirk, A. [Nuclear Research and Consultancy Group V.o.F., Petten (Netherlands); Jaspers, R. [Department of Applied Physics, Eindhoven University of Technology (Netherlands); Kiss, G. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Klinkhamer, F. [TNO Science and Industry, Partner in ITER-NL, P.O. Box 155, 2600 AD Delft (Netherlands); Koning, J.F. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, partner in the Trilateral Euregio Cluster and ITER-NL, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Kotov, V.; Krasikov, Y.; Krimmer, A. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany)

    2011-10-15

    The ITER core charge exchange recombination spectroscopy (core CXRS) diagnostic system is designed to provide experimental access to various measurement quantities in the ITER core plasma such as ion densities, temperatures and velocities. The implementation of the approved CXRS diagnostic principle on ITER faces significant challenges: First, a comparatively low CXRS signal intensity is expected, together with a high noise level due to bremsstrahlung, while the requested measurement accuracy and stability for the core CXRS system go far beyond the level commonly achieved in present-day fusion experiments. Second, the lifetime of the first mirror surface is limited due to either erosion by fast particle bombardment or deposition of impurities. Finally, the hostile technical environment on ITER imposes challenging boundary conditions for the diagnostic integration and operation, including high neutron loads, electro-magnetic loads, seismic events and a limited access for maintenance. A brief overview on the R and D and design activities for the core CXRS system is presented here, while the details are described in parallel papers.

  5. Measuring of fissile isotopes partial antineutrino spectra in direct experiment at nuclear reactor

    CERN Document Server

    Sinev, V V

    2009-01-01

    The direct measuring method is considered to get nuclear reactor antineutrino spectrum. We suppose to isolate partial spectra of the fissile isotopes by using the method of antineutrino spectrum extraction from the inverse beta decay positron spectrum applied at Rovno experiment. This admits to increase the accuracy of partial antineutrino spectra forming the total nuclear reactor spectrum. It is important for the analysis of the reactor core fuel composition and could be applied for non-proliferation purposes.

  6. A new anti-neutrino detection technique based on positronium tagging with plastic scintillators

    CERN Document Server

    Consolati, G; Jollet, C; Meregaglia, A; Minotti, A; Perasso, S; Tonazzo, A

    2015-01-01

    The main signature for anti-neutrino detection in reactor and geo-neutrino experiments based on scintillators is provided by the space-time coincidence of positron and neutron produced in the Inverse Beta Decay reaction. Such a signature strongly suppresses backgrounds and allows for measurements performed underground with a relatively high signal-to-background ratio. In an aboveground environment, however, the twofold coincidence technique is not sufficient to efficiently reject the high background rate induced by cosmogenic events. Enhancing the positron-neutron twofold coincidence efficiency has the potential to pave the way future aboveground detectors for reactor monitoring. We propose a new detection scheme based on a threefold coincidence, between the positron ionization, the ortho-positronium (o-Ps) decay, and the neutron capture, in a sandwich detector with alternated layers of plastic scintillator and aerogel powder. We present the results of a set of dedicated measurements on the achievable light y...

  7. Development of an advanced antineutrino detector for reactor monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Classen, T., E-mail: classen2@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Bernstein, A.; Bowden, N.S. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Cabrera-Palmer, B. [Sandia Livermore National Laboratories, Livermore, CA 94550 (United States); Ho, A.; Jonkmans, G. [Atomic Energy of Canada, Limited, Chalk River Laboratories, Chalk River, ON (Canada); Kogler, L.; Reyna, D. [Sandia Livermore National Laboratories, Livermore, CA 94550 (United States); Sur, B. [Atomic Energy of Canada, Limited, Chalk River Laboratories, Chalk River, ON (Canada)

    2015-01-21

    Here we present the development of a compact antineutrino detector for the purpose of nuclear reactor monitoring, improving upon a previously successful design. This paper will describe the design improvements of the detector which increases the antineutrino detection efficiency threefold over the previous effort. There are two main design improvements over previous generations of detectors for nuclear reactor monitoring: dual-ended optical readout and single volume detection mass. The dual-ended optical readout eliminates the need for fiducialization and increases the uniformity of the detector's optical response. The containment of the detection mass in a single active volume provides more target mass per detector footprint, a key design criteria for operating within a nuclear power plant. This technology could allow for real-time monitoring of the evolution of a nuclear reactor core, independent of reactor operator declarations of fuel inventories, and may be of interest to the safeguards community.

  8. Neutrino mass hierarchy determination at reactor antineutrino experiments

    CERN Document Server

    Yang, Guang

    2015-01-01

    After the neutrino mixing angle $\\theta_{13}$ has been precisely measured by the reactor antineutrino experiments, one of the most important open questions left in neutrino physics is the neutrino mass hierarchy. Jiangmen Underground Neutrino Observatory (JUNO) is designed to determine the neutrino mass hierarchy (MH) without exploring the matter effect. The JUNO site location is optimized to have the best sensitivity for the mass hierarchy determination. JUNO will employ a 20 kton liquid scintillator detector located in a laboratory 700 meters underground. The excellent energy resolution and PMT coverage will give us an unprecedented opportunity to reach a 3-4 $\\sigma$ precision. In this paper, the JUNO detector design and simulation work will be presented. Also, RENO-50, another medium distance reactor antineutrino experiment, will do a similar measurement. With the efforts of these experiments, it is very likely that the neutrino mass hierarchy will be determined in the next 10 years.

  9. Development of PROSPECT detectors for precision antineutrino studies

    CERN Document Server

    Norcini, Danielle

    2015-01-01

    PROSPECT, the Precision Reactor Oscillation and Spectrum Experiment, will use two segmented detectors positioned 7-20 m from the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory to measure the U-235 antineutrino spectrum and perform a search for short-baseline oscillations as a signature of eV-scale sterile neutrinos. PROSPECT has developed Li-6 loaded liquid scintillator detectors for efficient identification of reactor antineutrinos and has measured reactor and cosmogenic backgrounds in the HFIR reactor building. Multiple test detectors have been built, operated, and characterized at HFIR and elsewhere to understand the optical performance of the scintillator and pulse-shape discrimination capabilities for enhanced background rejection. The results from this R&D effort are discussed, in the context of the design and physics potential of PROSPECT.

  10. Reactor electron antineutrino disappearance in the Double Chooz experiment

    CERN Document Server

    Abe, Y; Anjos, J C dos; Barriere, J C; Bergevin, M; Bernstein, A; Bezerra, T J C; Bezrukhov, L; Blucher, E; Bowden, N S; Buck, C; Busenitz, J; Cabrera, A; Caden, E; Camilleri, L; Carr, R; Cerrada, M; Chang, P -J; Chimenti, P; Classen, T; Collin, A P; Conover, E; Conrad, J M; Crespo-Anadón, J I; Crum, K; Cucoanes, A; D'Agostino, M V; Damon, E; Dawson, J V; Dazeley, S; Dietrich, D; Djurcic, Z; Dracos, M; Durand, V; Ebert, J; Efremenko, Y; Elnimr, M; Etenko, A; Fallot, M; Fechner, M; von Feilitzsch, F; Felde, J; Franco, D; Franke, A J; Franke, M; Furuta, H; Gama, R; Gil-Botella, I; Giot, L; Goger-Neff, M; Gonzalez, L F G; Goodman, M C; Goon, J TM; Greiner, D; Haag, N; Hagner, C; Hara, T; Hartmann, F X; Haser, J; Hatzikoutelis, A; Hayakawa, T; Hofmann, M; Horton-Smith, G A; Hourlier, A; Ishitsuka, M; Jochum, J; Jollet, C; Jones, C L; Kaether, F; Kalousis, L N; Kamyshkov, Y; Kaplan, D M; Kawasaki, T; Keefer, G; Kemp, E; de Kerret, H; Kibe, Y; Konno, T; Kryn, D; Kuze, M; Lachenmaier, T; Lane, C E; Langbrandtner, C; Lasserre, T; Letourneau, A; Lhuillier, D; Lima, H P; Lindner, M; López-Castanõ, J M; LoSecco, J M; Lubsandorzhiev, B K; Lucht, S; McKee, D; Maeda, J; Maesano, C N; Mariani, C; Maricic, J; Martino, J; Matsubara, T; Mention, G; Meregaglia, A; Miletic, T; Milincic, R; Miyata, H; Mueller, Th A; Nagasaka, Y; Nakajima, K; Novella, P; Obolensky, M; Oberauer, L; Onillon, A; Osborn, A; Ostrovskiy, I; Palomares, C; Pepe, I M; Perasso, S; Perrin, P; Pfahler, P; Porta, A; Potzel, W; Reichenbacher, J; Reinhold, B; Remoto, A; Rohling, M; Roncin, R; Roth, S; Sakamoto, Y; Santorelli, R; Sato, F; Schonert, S; Schoppmann, S; Schwetz, T; Shaevitz, M H; Shimojima, S; Shrestha, D; Sida, J-L; Sinev, V; Skorokhvatov, M; Smith, E; Spitz, J; Stahl, A; Stancu, I; Stokes, L F F; Strait, M; Stuken, A; Suekane, F; Sukhotin, S; Sumiyoshi, T; Sun, Y; Svoboda, R; Terao, K; Tonazzo, A; Toups, M; Thi, H H Trinh; Valdiviesso, G; Veyssiere, C; Wagner, S; Watanabe, H; White, B; Wiebusch, C; Winslow, L; Worcester, M; Wurm, M; Yermia, F; Zimmer, V

    2012-01-01

    The Double Chooz experiment has observed 8,249 candidate electron antineutrino events in 227.93 live days with 33.71 GW-ton-years (reactor power x detector mass x livetime) exposure using a 10.3 cubic meter fiducial volume detector located at 1050 m from the reactor cores of the Chooz nuclear power plant in France. The expectation in case of theta13 = 0 is 8,937 events. The deficit is interpreted as evidence of electron antineutrino disappearance. From a rate plus spectral shape analysis we find sin^2 2{\\theta}13 = 0.109 \\pm 0.030(stat) \\pm 0.025(syst). The data exclude the no-oscillation hypothesis at 99.9% CL (3.1{\\sigma}).

  11. Which reactor antineutrino flux may be responsible for the anomaly?

    CERN Document Server

    Giunti, Carlo

    2016-01-01

    We investigate which among the reactor antineutrino fluxes from the decays of the fission products of $^{235}\\text{U}$, $^{238}\\text{U}$, $^{239}\\text{Pu}$, and $^{241}\\text{Pu}$ may be responsible for the reactor antineutrino anomaly. We find that it is the $^{235}\\text{U}$ flux, which contributes to the rates of all reactor neutrino experiments. From the fit of the data we obtain the precise determination $ \\sigma_{^{235}\\text{U}} = ( 6.34 \\pm 0.10 ) \\times 10^{-43} \\, \\text{cm}^2 / \\text{fission} $ of the $^{235}\\text{U}$ cross section per fission, which is more precise than the calculated value and differs from it by $2.0\\sigma$.

  12. Towards Earth AntineutRino TomograpHy (EARTH)

    OpenAIRE

    de Meijer, R. J.; Smit, F. D.; Brooks, F. D.; Fearick, R. W.; Woertche, H. J.; Mantovani, F

    2006-01-01

    The programme Earth AntineutRino TomograpHy (EARTH) proposes to build ten underground facilities each hosting a telescope. Each telescope consists of many detector modules, to map the radiogenic heat sources deep in the interior of the Earth by utilising direction sensitive geoneutrino detection. Recent hypotheses target the core-mantle boundary (CMB) as a major source of natural radionuclides and therefore of radiogenic heat. A typical scale of the processes that take place at the CMB is abo...

  13. Uncertainties in the Anti-neutrino Production at Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Djurcic, Zelimir; Detwiler, Jason A.; Piepke, Andreas; Foster Jr., Vince R.; Miller, Lester; Gratta, Giorgio

    2008-08-06

    Anti-neutrino emission rates from nuclear reactors are determined from thermal power measurements and fission rate calculations. The uncertainties in these quantities for commercial power plants and their impact on the calculated interaction rates in {bar {nu}}{sub e} detectors is examined. We discuss reactor-to-reactor correlations between the leading uncertainties, and their relevance to reactor {bar {nu}}{sub e} experiments.

  14. Estimating terrestrial uranium and thorium by antineutrino flux measurements

    OpenAIRE

    Dye, Stephen T.; Guillian, Eugene H.

    2008-01-01

    Uranium and thorium within the Earth produce a major portion of terrestrial heat along with a measurable flux of electron antineutrinos. These elements are key components in geophysical and geochemical models. Their quantity and distribution drive the dynamics, define the thermal history, and are a consequence of the differentiation of the Earth. Knowledge of uranium and thorium concentrations in geological reservoirs relies largely on geochemical model calculations. This research report desc...

  15. Science Potential of a Deep Ocean Antineutrino Observatory

    OpenAIRE

    Dye, Steve

    2006-01-01

    This paper presents science potential of a deep ocean antineutrino observatory under development at Hawaii. The observatory design allows for relocation from one site to another. Positioning the observatory some 60 km distant from a nuclear reactor complex enables precision measurement of neutrino mixing parameters, leading to a determination of neutrino mass hierarchy. At a mid-Pacific location the observatory measures the flux and ratio of uranium and thorium decay neutrinos from earth's ma...

  16. Investigation of Large LGB Detectors for Antineutrino Detection

    OpenAIRE

    Nelson, P; Bowden, N. S.

    2011-01-01

    A detector material or configuration that can provide an unambiguous indication of neutron capture can substantially reduce random coincidence backgrounds in antineutrino detection and capture-gated neutron spectrometry applications. Here we investigate the performance of such a material, a composite of plastic scintillator and $^6$Li$_6^{nat}$Gd$(^{10}$BO$_{3})_{3}$:Ce (LGB) crystal shards of ~1 mm dimension and comprising 1% of the detector by mass. While it is found that the optical propag...

  17. Neutrino Geophysics at Baksan I: Possible Detection of Georeactor Antineutrinos

    CERN Document Server

    Domogatski, G; Mikaelyan, L A; Sinev, V

    2004-01-01

    J.M. Herndon in 90-s proposed a natural nuclear fission georeactor at the center of the Earth with a power output of 3-10 TW as an energy source to sustain the Earth magnetic field. R.S. Raghavan in 2002 y. pointed out that under certain condition antineutrinos generated in georeactor can be detected using massive scintillation detectors. We consider the underground Baksan Neutrino Observatory (4800 m.w.e.) as a possible site for developments in Geoneutrino physics. Here the intrinsic background level of less than one event/year in a liquid scintillation ~1000 target ton detector can be achieved and the main source of background is the antineutrino flux from power reactors. We find that this flux is ~10 times lower than at KamLAND detector site and two times lower than at Gran Sasso laboratory and thus at Baksan the georeactor hypothesis can be conclusively tested. We also discuss possible search for composition of georector burning nuclear fuel by analysis of the antineutrino energy spectrum.

  18. The double chooz experiment: simulation of reactor antineutrino spectra

    International Nuclear Information System (INIS)

    The Double Chooz experiment aims to study the oscillations of electron antineutrinos produced by the Chooz nuclear power station, located in France, in the Ardennes region. It will lead to an unprecedented accuracy on the value of the mixing angle θ13. Improving the current knowledge on this parameter, given by the Chooz experiment, requires a reduction of both statistical and systematic errors, that is to say not only observing a large data sample, but also controlling the experimental uncertainties involved in the production and detection of electron antineutrinos. The use of two identical detectors will cancel most of the experimental systematic uncertainties limiting the sensitivity to the value of the mixing angle. We present in this thesis, simulations of reactor antineutrino spectra that were carried out in order to control the sources of systematic uncertainty related to the production of these particles by the plant. We also discuss our work on controlling the normalization error of the experiment through the precise determination of the number of target protons by a weighing measurement and through the study of the fiducial volume of the detectors which requires an accurate modeling of neutron physics. After three years of data taking with two detectors, Double Chooz will be able to disentangle an oscillation signal for sin22θ13 ≥ 0.05 (at 3σ) or, if no oscillations are observed, to put a limit of sin22θ13 ≤ 0.03 at 90% C.L. (author)

  19. Extension of a Kinetic-Theory Approach for Computing Chemical-Reaction Rates to Reactions with Charged Particles

    Science.gov (United States)

    Liechty, Derek S.; Lewis, Mark J.

    2010-01-01

    Recently introduced molecular-level chemistry models that predict equilibrium and nonequilibrium reaction rates using only kinetic theory and fundamental molecular properties (i.e., no macroscopic reaction rate information) are extended to include reactions involving charged particles and electronic energy levels. The proposed extensions include ionization reactions, exothermic associative ionization reactions, endothermic and exothermic charge exchange reactions, and other exchange reactions involving ionized species. The extensions are shown to agree favorably with the measured Arrhenius rates for near-equilibrium conditions.

  20. Charge Exchange-induced X-Ray Emission of Fe xxv and Fe xxvI via a Streamlined Model

    Science.gov (United States)

    Mullen, P. D.; Cumbee, R. S.; Lyons, D.; Stancil, P. C.

    2016-06-01

    Charge exchange (CX) is an important process for the modeling of X-ray spectra obtained by the Chandra, XMM-Newton, and Suzaku X-ray observatories, as well as the anticipated Astro-H mission. The understanding of the observed X-ray spectra produced by many astrophysical environments is hindered by the current incompleteness of available atomic and molecular data—especially for CX. Here, we implement a streamlined program set that applies quantum defect methods and the Landau–Zener theory to generate total, n-resolved, and n{\\ell }S-resolved cross sections for any given projectile ion/target CX collision. By using these data in a cascade model for X-ray emission, theoretical spectra for such systems can be predicted. With these techniques, Fe25+ and Fe26+ CX collisions with H, He, H2, N2, H2O, and CO are studied for single-electron capture (SEC). These systems have been selected because they illustrate computational difficulties for high projectile charges. Furthermore, Fe xxv and Fe xxvi emission lines have been detected in the Galactic center and Galactic ridge. Theoretical X-ray spectra for these collision systems are compared to experimental data generated by an electron-beam ion trap study. Several ℓ-distribution models have been tested for Fe25+ and Fe26+ SEC. Such analyses suggests that commonly used ℓ-distribution models struggle to accurately reflect the true distribution of electron capture as understood by more advanced theoretical methods.

  1. Strong sensitivity of x-ray emission lines following charge exchange between highly charged ions and H (1 s ) in weakly screened media

    Science.gov (United States)

    Cariatore, N. D.; Otranto, S.

    2015-11-01

    We use the classical trajectory Monte Carlo method to analyze charge exchange processes between fully stripped projectiles with H (1 s ) in a screened environment at impact energies in the range 18 eV/amu to 10 keV/amu. For Fe+26 projectiles, (n ,l )-state selective charge exchange and line emission cross sections are presented for Debye screening lengths from 15 a.u. up to the unscreened case limit. At low-impact energies, a strong dependence of the hardness ratio on the Debye screening length is found. We show that such strong dependence also evidences itself for Ne+10,P+15,Ar+18, and Kr+36 projectiles. Clear indications of this dependence are noticeable in the photonic spectra even for large screening lengths (˜100 a.u.).

  2. Antineutrino Neutral Current Interactions in MiniBooNE

    Energy Technology Data Exchange (ETDEWEB)

    Dharmapalan, Ranjan [Univ. of Alabama, Tuscaloosa, AL (United States)

    2012-01-01

    This dissertation reports the antineutrino-nucleus neutral current elastic scattering cross section on CH2 measured by the MiniBooNE experiment located in Batavia, IL. The data set consists of 60,605 events passing the selection cuts corresponding to 10.1×1020 POT, which represents the world’s largest sample of antineutrino neutral current elastic scattering events. The final sample is more than one order of magnitude lager that the previous antineutrino NCE scattering cross section measurement reported by the BNL E734 experiment. The measurement presented in this dissertation also spans a wider range in Q2, including the low-Q2 regime where the cross section rollover is clearly visible. A X2-based minimization was performed to determine the best value of the axial mass, MA and the Pauli blocking scaling function, that matches the antineutrino NCE scattering data. However, the best fit values of MA=1.29 GeV and K=1.026 still give a relatively poor X2, which suggests that the underlying nuclear model (based largely on the relativistic Fermi gas model) may not be an accurate representation for this particular interaction. Additionally, we present a measurement of the antineutrino/neutrino-nucleus NCE scattering cross section ratio. The neutrino mode NCE sample used in this study, corresponding to 6.4 × 1020 POT, is also the world’s largest sample (also by an order of magnitude). We have demonstrated that the ratio measurement is robust, as most of the correlated errors cancel, as expected. Furthermore, this ratio also proves to be rather insensitive to variations in the axial mass and the Pauli blocking parameter. This is the first time that this ratio has been experimentally reported. We believe this measurement will aid the theoretical physics community to test various model predictions of neutrino-nucleon/nucleus interactions.

  3. Use of Antineutrino Detectors for Nuclear Reactor Safeguards Effectiveness Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, A; Lambert, H E; Elayat, H A; O' Connell, W J; Rexroth, P; Baldwin, G; Bowden, N; Huelskamp, R

    2006-06-05

    As described in an earlier article [1], important information regarding reactor power and the amount and type of fissile material in reactor cores can be determined by measuring the antineutrino rate and energy spectrum, using a cubic meter scale antineutrino detector at tens of meters standoff from the core. Current International Atomic Energy Agency (IAEA) safeguards techniques do not provide such real-time quantitative information regarding core power levels and isotopic composition. The possible benefits of this approach are several and have been discussed in the earlier article. One key advantage is that the method gives the inspecting agency completely independent access to real-time information on the operational status and fissile content of the core. Furthermore, the unattended and non-intrusive nature of the technology may reduce the monitoring burden on the plant operator, even though more information is being provided than is available within the current IAEA safeguards regime. Here we present a detailed analytical framework for measuring the impact that such a detector might have on IAEA safeguards, if implemented. To perform the analysis, we will use initial data from our operating detector and a standard analysis technique for safeguards regimes, developed at Lawrence Livermore National Laboratory. Because characterization of the prototype detector is still underway, and because improvements in the prototype could have important impact on safeguards performance, the results presented here should be understood to be preliminary, and not reflective of the ultimate performance of the system. The structure of this paper is as follows. Reactor safeguards and the relevant properties of antineutrino detectors are briefly reviewed. A set of hypothetical diversion scenarios are then described, and one of these is analyzed using the Lawrence Livermore National Laboratory Integrated Safeguards System Analysis Tool (LISSAT) The probability of successful

  4. Antineutrino Oscillations and a Search for Non-standard Interactions with the MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Isvan, Zeynep [Univ. of Pittsburgh, PA (United States)

    2012-01-01

    MINOS searches for neutrino oscillations using the disappearance of muon neutrinos from the NuMI beam at Fermilab between two detectors. The Near Detector, located near the source, measures the beam composition before flavor change occurs. The energy spectrum is measured again at the Far Detector after neutrinos travel a distance. The mixing angle and mass splitting between the second and third mass states are extracted from the energy dependent difference between the spectra at the two detectors. NuMI is able to produce an antineutrino-enhanced beam as well as a neutrino-enhanced beam. Collecting data in antineutrino-mode allows the direct measurement of antineutrino oscillation parameters. From the analysis of the antineutrino mode data we measure $|\\Delta\\bar{m}^{2}_{\\text{atm}}| = 2.62^{+0.31}_{-0.28}\\times10^{-3}\\text{eV}^{2}$ and $\\sin^{2}(2\\bar{\\theta})_{23} = 0.95^{+0.10}_{-0.11}$, which is the most precise measurement of antineutrino oscillation parameters to date. A difference between neutrino and antineutrino oscillation parameters may indicate new physics involving interactions that are not part of the Standard Model, called non-standard interactions, that alter the apparent disappearance probability. Collecting data in neutrino and antineutrino mode independently allows a direct search for non-standard interactions. In this dissertation non-standard interactions are constrained by a combined analysis of neutrino and antineutrino datasets and no evidence of such interactions is found.

  5. Nuclear security applications of antineutrino detectors : current capabilities and future prospects.

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, A.; Goodman, M.; Baldwin, G.; Learned, J.; Lund, J.; Reyna, D.; Svaboda, R. (High Energy Physics); (LLNL); (SNL); (LANL); (Univ. of Hawaii); (Univ. of California)

    2010-12-10

    Antineutrinos are electrically neutral, nearly massless fundamental particles produced in large numbers in the cores of nuclear reactors and in nuclear explosions. In the half century since their discovery, major advances in the understanding of their properties, and in detector technology, have opened the door to a new discipline - Applied Antineutrino Physics. Because antineutrinos are inextricably linked to the process of nuclear fission, there are many applications of interest in nuclear nonproliferation. This paper presents a comprehensive survey of applied antineutrino physics relevant for nonproliferation, summarizes recent advances in the field, describes the overlap of this nascent discipline with other ongoing fundamental and applied antineutrino research, and charts a course for research and development for future applications. It is intended as a resource for policymakers, researchers, and the wider nuclear nonproliferation community.

  6. A study of antineutrino spectra from spent nuclear fuel at Daya Bay

    Institute of Scientific and Technical Information of China (English)

    ZHOU Bin; RUAN Xi-Chao; NIE Yang-Bo; ZHOU Zu-Ying; AN Feng-Peng; CAO Jun

    2012-01-01

    The Daya Bay Reactor Antineutrino Experiment is designed to determine the as yet unknown neutrino mixing angle,θ13,by measuring the disappearance of electron antineutrinos from several nuclear reactor cores.The projected sensitivity in sin2(2θ13) of better than 0.01 at a 90% CL should be achieved after three years of data-taking.Antineutrinos emitted from spent nuclear fuel (SNF) distort the soft part of the energy spectrum.In this article,a calculation of the antineutrino spectra from the long-life isotopes in SNF is performed.A non-equilibrium generation of long half-life isotopes during the running time of the reactor is also analyzed.Finally,we show that the antineutrino event rate contribution from SNF,which has been stored in the SNF pool for several years,may be non-negligible.

  7. Neutrino Geophysics at Baksan I: Possible Detection of Georeactor Antineutrinos

    OpenAIRE

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

    2004-01-01

    J.M. Herndon in 90-s proposed a natural nuclear fission georeactor at the center of the Earth with a power output of 3-10 TW as an energy source to sustain the Earth magnetic field. R.S. Raghavan in 2002 y. pointed out that under certain condition antineutrinos generated in georeactor can be detected using massive scintillation detectors. We consider the underground Baksan Neutrino Observatory (4800 m.w.e.) as a possible site for developments in Geoneutrino physics. Here the intrinsic backgro...

  8. Science Potential of a Deep Ocean Antineutrino Observatory

    CERN Document Server

    Dye, S

    2007-01-01

    This paper presents science potential of a deep ocean antineutrino observatory under development at Hawaii. The observatory design allows for relocation from one site to another. Positioning the observatory some 60 km distant from a nuclear reactor complex enables precision measurement of neutrino mixing parameters, leading to a determination of neutrino mass hierarchy. At a mid-Pacific location the observatory measures the flux and ratio of uranium and thorium decay neutrinos from earth's mantle and performs a sensitive search for a hypothetical natural fission reactor in earth's core. A subsequent deployment at another mid-ocean location would test lateral heterogeneity of uranium and thorium in earth's mantle.

  9. Experimental Study Of Terrestrial Electron Anti-neutrinos With Kamland

    CERN Document Server

    Tolich, N R

    2005-01-01

    The analysis presented here uses Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) to measure the rate of electron anti-neutrinos, ne&d1;' s , produced from terrestrial 238U and 212Th. 238U and 212Th are thought to be the main heat source driving mantle convection in the Earth, which in turn is responsible for plate tectonics. The total terrestrial 238U and 212Th content has been estimated from Earth models and rock samples from a very small fraction of the Earth. Until now there have been no direct measurements. Since ne&d1;' s have an exceedingly small cross section, they propagate undisturbed in the Earth interior, and their measurement near the Earth surface can be used to gain information on their sources. Based on a total of (2.63 ± 0.19) × 1031 target proton-years (0.506 kton- years), the 90% confidence interval for the total number of terrestrial 238U and 212Th ne&d1;' s detected is 4 to 40. This is consistent with the best models of terrestrial 23...

  10. Contribution of recently measured nuclear data to reactor antineutrino energy spectra predictions

    Directory of Open Access Journals (Sweden)

    Fallot M.

    2013-12-01

    Full Text Available This paper attempts to summarize the actual problematic of reactor antineutrino energy spectra in the frame of fundamental and applied neutrino physics. Nuclear physics is an important ingredient of reactor antineutrino experiments. These experiments are motivated by neutrino oscillations, i.e. the measure of the θ13 mixing angle. In 2011, after a new computation of the reactor antineutrino energy spectra, based on the conversion of integral data of the beta spectra from 235U, and 239;241Pu, a deficit of reactor antineutrinos measured by short baseline experiments was pointed out. This is called the “reactor anomaly”, a new puzzle in the neutrino physics area. Since then, numerous new experimental neutrino projects have emerged. In parallel, computations of the antineutrino spectra independant from the ILL data would be desirable. One possibility is the use of the summation method, summing all the contributions of the fission product beta decay branches that can be found in nuclear databases. Studies have shown that in order to obtain reliable summation antineutrino energy spectra, new nuclear physics measurements of selected fission product beta decay properties are required. In these proceedings, we will present the computation methods of reactor antineutrino energy spectra and the impact of recent beta decay measurements on summation method spectra. The link of these nuclear physics studies with short baseline line oscillation search will be drawn and new neutrino physics projects at research reactors will be briefly presented.

  11. Comment on "Classical description of H (1 s ) and H*(n =2 ) for cross-section calculations relevant to charge-exchange diagnostics"

    Science.gov (United States)

    Jorge, A.; Errea, L. F.; Illescas, Clara; Méndez, L.

    2016-06-01

    Cariatore et al. [Phys. Rev. A 91, 042709 (2015), 10.1103/PhysRevA.91.042709] have introduced a modification of the classical trajectory Monte Carlo (CTMC) method, specially conceived to provide an accurate representation of charge-exchange processes between highly charged ions and H (1 s ) , H*(n =2 ) . We point out that this new CTMC treatment is based on nonstable initial distributions for H*(n =2 ) targets and an improper description of the H (1 s ) target.

  12. Solar Wind Charge Exchange X-ray emission from Mercury’s exosphere: Detectability with Bepi Colombo’s MIXS spectrometer

    Science.gov (United States)

    Koutroumpa, Dimitra; Dennerl, Konrad; Leblanc, François; Modolo, Ronan

    2015-11-01

    We have conducted preliminary hybrid simulations to calculate the Solar Wind Charge Exchange (SWCX) X-ray emission in Mercury’s exosphere. Our results imply that the OVII triplet emission intensity for standard slow solar wind conditions is of the same order as the one predicted by simulations for Mars and measured by Chandra in past observations of Mars. Using an oversimplified detector and observation geometry we explore the detectability of Mercury's SWCX emission by the MIXS spectrometer on board Bepi Colombo’s planetary orbiter (MPO).

  13. DXL: A Sounding Rocket Mission for the Study of Solar Wind Charge Exchange and Local Hot Bubble X-Ray Emission

    Science.gov (United States)

    Galeazzi, M.; Prasai, K.; Uprety, Y.; Chiao, M.; Collier, M. R.; Koutroumpa, D.; Porter, F. S.; Snowden, S.; Cravens, T.; Robertson, I.; Kuntz, K. D.; Lepri, S.; McCammon, D.

    2011-01-01

    The Diffuse X-rays from the Local galaxy (DXL) mission is an approved sounding rocket project with a first launch scheduled around December 2012. Its goal is to identify and separate the X-ray emission generated by solar wind charge exchange from that of the local hot bubble to improve our understanding of both. With 1,000 square centimeters proportional counters and grasp of about 10 square centimeters sr both in the 1/4 and 3/4 keV bands, DXL will achieve in a 5-minute flight what cannot be achieved by current and future X-ray satellites.

  14. Measurement of Anomalously Strong Emission from the 1s-9p Transition in the Spectrum of H-like Phosphorus Following Charge Exchange with Molecular Hydrogen

    Science.gov (United States)

    Leutenegger, M. A.; Beiersdorfer, P.; Brown, G. V.; Kelley, R. L.; Porter, F. S.

    2010-01-01

    We have measured K-shell x-ray spectra of highly ionized argon and phosphorus following charge exchange with molecular hydrogen at low collision energy in an electron beam ion trap using an x-ray calorimeter array with approx.6 eV resolution. We find that the emission at the high-end of the Lyman series is greater by a factor of two for phosphorus than for argon, even though the measurement was performed concurrently and the atomic numbers are similar. This does not agree with current theoretical models and deviates from the trend observed in previous measurements.

  15. DXL: a sounding rocket mission for the study of solar wind charge exchange and local hot bubble X-ray emission

    CERN Document Server

    Galeazzi, M; Collier, M R; Cravens, T; Koutroumpa, D; Kuntz, K D; Lepri, S; McCammon, D; Porter, F S; Prasai, K; Robertson, I; Snowden, S; Uprety, Y

    2011-01-01

    The Diffuse X-rays from the Local galaxy (DXL) mission is an approved sounding rocket project with a first launch scheduled around December 2012. Its goal is to identify and separate the X-ray emission generated by solar wind charge exchange from that of the local hot bubble to improve our understanding of both. With 1,000 cm2 proportional counters and grasp of about 10 cm2 sr both in the 1/4 and 3/4 keV bands, DXL will achieve in a 5-minute flight what cannot be achieved by current and future X-ray satellites.

  16. Laboratory measurements compellingly support charge-exchange mechanism for the 'dark matter' $\\sim$3.5 keV X-ray line

    OpenAIRE

    Shah, Chintan; Dobrodey, Stepan; Bernitt, Sven; Steinbrügge, René; López-Urrutia, José R. Crespo; Gu, Liyi; Kaastra, Jelle

    2016-01-01

    The reported observations of an unidentified X-ray line feature at $\\sim$3.5 keV have driven a lively discussion about its possible dark matter origin. Motivated by this, we have measured the \\emph{K}-shell X-ray spectra of highly ionized bare sulfur ions following charge exchange with gaseous molecules in an electron beam ion trap, as a source of or a contributor to this X-ray line. We produce $\\mathrm{S}^{16+}$ and $\\mathrm{S}^{15+}$ ions and let them capture electrons in collision with tho...

  17. Measuring one-dimensional and two-dimensional impurity density profiles on TEXTOR using combined charge exchange-beam emission spectroscopy and ultrasoft x-ray tomography

    Science.gov (United States)

    De Bock, M.; Jakubowska, K.; Hellermann, M. von; Jaspers, R.; Donné, A. J. H.; Shmaenok, L.

    2004-10-01

    Two techniques are presented that allow us to measure impurity density profiles in the TEXTOR tokamak plasma. The one-dimensional profiles are gathered by charge exchange recombination spectroscopy (CXRS) in combination with beam emission spectroscopy (BES). Combining CXRS and BES eliminate the need for absolute calibration. For two-dimensional profiles an ultrasoft x-ray tomography system has been developed. The system is spectrally resolved and produces local emissivity profiles of several ionization stages of impurities. Both systems are presently being commissioned. They are complementary and give an insight into the impurity distribution and transport in plasmas.

  18. Neutrino and antineutrino inclusive charged-current cross section measurements with the MINOS near detector

    OpenAIRE

    Adamson, P.; Andreopoulos, C.; Arms, K. E.; Armstrong, R.; Auty, D. J.; Ayres, D. S.; Backhouse, C.; Barnes, JR; Barr, G.; Barrett, W. L.; Devenish, N. E.; Falk, E.; Harris, P.G.; Hartnell, J.; et al, ...

    2010-01-01

    The energy dependence of the neutrino-iron and antineutrino-iron inclusive charged-current cross sections and their ratio have been measured using a high-statistics sample with the MINOS Near Detector exposed to the NuMI beam from the Main Injector at Fermilab. Neutrino and antineutrino fluxes were determined using a low hadronic energy subsample of charged-current events. We report measurements of neutrino-Fe (antineutrinoFe) cross section in the energy range 3-50 GeV (5-50 GeV) with precisi...

  19. Can Radiogenic Heat Sources Inside the Earth be located by their Antineutrino incoming Directions?

    CERN Document Server

    Domogatsky, G; Mikaelyan, L; Sinev, V

    2004-01-01

    Antineutrinos born in the U and Th decay chains inside the Earth (``Geoneutrinos'') carry out information on the amount and distribution of radiogenic heat sources, which is of fundamental importance for geophysics. Models of the Earth distribute U and Th masses mainly between the continental crust and the lower mantle. It has been much discussed recently that a number of detectors stationed at appropriate geographical sites can separate the crust and mantle contributions. In present work we analyze directional separation of antineutrino signals arriving from the crust and the lower mantle with only one detector. We find that with a ~30-kton liquid scintillation antineutrino spectrometer using $\\bar{{\

  20. Decay heat and anti-neutrino energy spectra in fission fragments from total absorption spectroscopy

    Science.gov (United States)

    Rykaczewski, Krzysztof

    2015-10-01

    Decay studies of over forty 238U fission products have been studied using ORNL's Modular Total Absorption Spectrometer. The results are showing increased decay heat values, by 10% to 50%, and the energy spectra of anti-neutrinos shifted towards lower energies. The latter effect is resulting in a reduced number of anti-neutrinos interacting with matter, often by tens of percent per fission product. The results for several studied nuclei will be presented and their impact on decay heat pattern in power reactors and reactor anti-neutrino physics will be discussed.

  1. Search for differences in oscillation parameters for atmospheric neutrinos and antineutrinos at Super-Kamiokande.

    Science.gov (United States)

    Abe, K; Hayato, Y; Iida, T; Ikeda, M; Iyogi, K; Kameda, J; Koshio, Y; Kozuma, Y; Miura, M; Moriyama, S; Nakahata, M; Nakayama, S; Obayashi, Y; Sekiya, H; Shiozawa, M; Suzuki, Y; Takeda, A; Takenaga, Y; Takeuchi, Y; Ueno, K; Ueshima, K; Watanabe, H; Yamada, S; Yokozawa, T; Ishihara, C; Kaji, H; Lee, K P; Kajita, T; Kaneyuki, K; McLachlan, T; Okumura, K; Shimizu, Y; Tanimoto, N; Martens, K; Vagins, M R; Labarga, L; Magro, L M; Dufour, F; Kearns, E; Litos, M; Raaf, J L; Stone, J L; Sulak, L R; Goldhaber, M; Bays, K; Kropp, W R; Mine, S; Regis, C; Smy, M B; Sobel, H W; Ganezer, K S; Hill, J; Keig, W E; Jang, J S; Kim, J Y; Lim, I T; Albert, J B; Scholberg, K; Walter, C W; Wendell, R; Wongjirad, T M; Tasaka, S; Learned, J G; Matsuno, S; Hasegawa, T; Ishida, T; Ishii, T; Kobayashi, T; Nakadaira, T; Nakamura, K; Nishikawa, K; Nishino, H; Oyama, Y; Sakashita, K; Sekiguchi, T; Tsukamoto, T; Suzuki, A T; Minamino, A; Nakaya, T; Fukuda, Y; Itow, Y; Mitsuka, G; Tanaka, T; Jung, C K; Taylor, I; Yanagisawa, C; Ishino, H; Kibayashi, A; Mino, S; Mori, T; Sakuda, M; Toyota, H; Kuno, Y; Kim, S B; Yang, B S; Ishizuka, T; Okazawa, H; Choi, Y; Nishijima, K; Koshiba, M; Yokoyama, M; Totsuka, Y; Chen, S; Heng, Y; Yang, Z; Zhang, H; Kielczewska, D; Mijakowski, P; Connolly, K; Dziomba, M; Wilkes, R J

    2011-12-01

    We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3)  eV2, 1.0) and is consistent with the overall Super-K measurement. PMID:22242990

  2. Search for Differences in Oscillation Parameters for Atmospheric Neutrinos and Antineutrinos at Super-Kamiokande

    CERN Document Server

    Abe, K; Iida, T; Ikeda, M; Iyogi, K; Kameda, J; Koshio, Y; Kozuma, Y; Miura, M; Moriyama, S; Nakahata, M; Nakayama, S; Obayashi, Y; Sekiya, H; Shiozawa, M; Suzuki, Y; Takeda, A; Takenaga, Y; Takeuchi, Y; Ueno, K; Ueshima, K; Watanabe, H; Yamada, S; Yokozawa, T; Ishihara, C; Kaji, H; Lee, K P; Kajita, T; Kaneyuki, K; McLachlan, T; Okumura, K; Shimizu, Y; Tanimoto, N; Martens, K; Vagins, M R; Labarga, L; Magro, L M; Dufour, F; Kearns, E; Litos, M; Raaf, J L; Stone, J L; Sulak, L R; Goldhaber, M; Bays, K; Kropp, W R; Mine, S; Regis, C; Smy, M B; Sobel, H W; Ganezer, K S; Hill, J; Keig, W E; Jang, J S; Kim, J Y; Lim, I T; Albert, J B; Scholberg, K; Walter, C W; Wendell, R; Wongjirad, T M; Tasaka, S; Learned, J G; Matsuno, S; Hasegawa, T; Ishida, T; Ishii, T; Kobayashi, T; Nakadaira, T; Nakamura, K; Nishikawa, K; Nishino, H; Oyama, Y; Sakashita, K; Sekiguchi, T; Tsukamoto, T; Suzuki, A T; Minamino, A; Nakaya, T; Fukuda, Y; Itow, Y; Mitsuka, G; Tanaka, T; Jung, C K; Taylor, I; Yanagisawa, C; Ishino, H; Kibayashi, A; Mino, S; Mori, T; Sakuda, M; Toyota, H; Kuno, Y; Kim, S B; Yang, B S; Ishizuka, T; Okazawa, H; Choi, Y; Nishijima, K; Koshiba, M; Yokoyama, M; Totsuka, Y; Chen, S; Heng, Y; Yang, Z; Zhang, H; Kielczewska, D; Mijakowski, P; Connolly, K; Dziomba, M; Wilkes, R J

    2011-01-01

    We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande -I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best fit antineutrino mixing is found to be at (dm2bar, sin2 2 thetabar) = (2.0x10^-3 eV^2, 1.0) and is consistent with the overall Super-K measurement.

  3. The origin of the 'local' 1/4 keV X-ray flux in both charge exchange and a hot bubble

    CERN Document Server

    Galeazzi, M; Collier, M R; Cravens, T; Koutroumpa, D; Kuntz, K D; Lallement, R; Lepri, S T; McCammon, D; Morgan, K; Porter, F S; Robertson, I P; Snowden, S L; Thomas, N E; Uprety, Y; Ursino, E; Walsh, B M

    2014-01-01

    The Solar neighborhood is the closest and most easily studied sample of the Galactic interstellar medium, an understanding of which is essential for models of star formation and galaxy evolution. Observations of an unexpectedly intense diffuse flux of easily-absorbed 1/4 keV X rays, coupled with the discovery that interstellar space within ~100 pc of the Sun is almost completely devoid of cool absorbing gas led to a picture of a "local cavity" filled with X-ray emitting hot gas dubbed the local hot bubble. This model was recently upset by suggestions that the emission could instead be produced readily within the solar system by heavy solar wind ions charge exchanging with neutral H and He in interplanetary space, potentially removing the major piece of evidence for the existence of million-degree gas within the Galactic disk. Here we report results showing that the total solar wind charge exchange contribution is 40% +/- 5% (stat) +/- 5% (sys) of the 1/4 keV flux in the Galactic plane. The fact that the measu...

  4. Laboratory measurements compellingly support charge-exchange mechanism for the 'dark matter' $\\sim$3.5 keV X-ray line

    CERN Document Server

    Shah, Chintan; Bernitt, Sven; Steinbrügge, René; López-Urrutia, José R Crespo; Gu, Liyi; Kaastra, Jelle

    2016-01-01

    The reported observations of an unidentified X-ray line feature at $\\sim$3.5 keV have driven a lively discussion about its possible dark matter origin. Motivated by this, we have measured the \\emph{K}-shell X-ray spectra of highly ionized bare sulfur ions following charge exchange with gaseous molecules in an electron beam ion trap, as a source of or a contributor to this X-ray line. We produce $\\mathrm{S}^{16+}$ and $\\mathrm{S}^{15+}$ ions and let them capture electrons in collision with those molecules with the electron beam turned off while recording X-ray spectra. We observed a charge-exchanged-induced X-ray feature at the Lyman series limit (3.47 $\\pm$ 0.06 keV). The inferred X-ray energy is in full agreement with the reported astrophysical observations and supports the novel scenario proposed by Gu and Kaastra (A \\& A \\textbf{584}, {L11} (2015)).

  5. Uncertainties analysis of fission fraction for reactor antineutrino experiments using DRAGON

    CERN Document Server

    Ma, X B; Chen, Y X; Zhong, W L; An, F P

    2014-01-01

    Rising interest in nuclear reactors as a source of antineutrinos for experiments motivates validated, fast, and accessible simulation to predict reactor rates. First, DRAGON was developed to calculate the fission rates of the four most important isotopes in fissions,235U,238U,239Pu and141Pu, and it was validated for PWRs using the Takahama benchmark. The fission fraction calculation function was validated through comparing our calculation results with MIT's results. we calculate the fission fraction of the Daya Bay reactor core, and compare its with those calculated by the commercial reactor simulation program SCIENCE, which is used by the Daya Bay nuclear power plant, and the results was consist with each other. The uncertainty of the antineutrino flux by the fission fraction was studied, and the uncertainty of the antineutrino flux by the fission fraction simulation is 0.6% per core for Daya Bay antineutrino experiment.

  6. A new approach to anti-neutrino running in long baseline neutrino oscillation experiments

    CERN Document Server

    Agarwalla, Sanjib K; Link, Jonathan M; Mohapatra, Debabrata

    2010-01-01

    We study the possibility to replace the anti-neutrino run of a long baseline neutrino oscillation experiment, with anti-neutrinos from muon decay at rest. The low energy of these neutrinos allows the use of inverse beta decay for detection in a Gadolinium-doped water Cerenkov detector. We show that this approach yields a factor of five times larger anti-neutrino event sample. The resulting discovery reaches in theta_13, the mass hierarchy and leptonic CP violation are compared with those from a conventional superbeam experiment with combined neutrino and anti-neutrino running. We find that this approach yields a greatly improved reach for CP violation and theta_13 while leaving the ability to measure the mass hierarchy intact.

  7. An Improved Measurement of Electron Antineutrino Disappearance at Daya Bay

    CERN Document Server

    Webber, David M

    2012-01-01

    The theory of neutrino oscillations explains changes in neutrino flavor, count rates, and spectra from solar, atmospheric, accelerator, and reactor neutrinos. These oscillations are characterized by three mixing angles and two mass-squared differences. The solar mixing angle, {\\theta}_12, and the atmospheric mixing angle, {\\theta}_23, have been well measured, but until recently the neutrino mixing angle {\\theta}_13 was not well known. The Daya Bay experiment, located northeast of Hong Kong at the Guangdong Nuclear Power Complex in China, has made a precise measurement of electron antineutrino disappearance using six functionally-identical gadolinium-doped liquid scintillator-based detectors at three sites with distances between 364 and 1900 meters from six reactor cores. This proceeding describes the Daya Bay updated result, using 127 days of good run time collected between December 24, 2011 and May 11, 2012. For the far site, the ratio of the observed number of events to the expected number of events assumin...

  8. Detection of reactor antineutrino coherent scattering off nuclei with a two-phase noble gas detector

    OpenAIRE

    Akimov, Dmitri; Bondar, Alexander; Burenkov, Alexander; Buzulutskov, Alexei

    2009-01-01

    Estimation of the signal amplitudes and counting rates for coherent scattering of reactor antineutrino off atomic nuclei in two-phase xenon and argon detectors has been done. A conceptual design of detector based on the existing technologies and experience has been proposed. It is shown that a condensed xenon/argon two-phase detector possesses the necessary sensitivity for the use in experiment on detection of coherent scattering of the reactor antineutrino off nuclei. It is shown that a two-...

  9. Recoilless Resonance Absorption of Tritium Antineutrinos and Time-Energy Uncertainty Relation

    OpenAIRE

    Bilenky, S. M.

    2007-01-01

    We discuss neutrino oscillations in an experiment with M\\"ossbauer recoilless resonance absorbtion of tritium antineutrinos, proposed recently by Raghavan. We demonstrate that small energy uncertainty of antineutrinos which ensures a large resonance absorption cross section is in a conflict with the energy uncertainty which, according to the time-energy uncertainty relation, is necessary for neutrino oscillations to happen. The search for neutrino oscillations in the M\\"ossbauer neutrino expe...

  10. Remote safeguards and monitoring of reactors with antineutrinos.

    Energy Technology Data Exchange (ETDEWEB)

    Reyna, David

    2010-10-01

    The current state-of-the-art in antineutrino detection is such that it is now possible to remotely monitor the operational status, power levels and fissile content of nuclear reactors in real-time. This non-invasive and incorruptible technique has been demonstrated at civilian power reactors in both Russia and the United States and has been of interest to the IAEA Novel Technologies Unit for several years. Expert's meetings were convened at IAEA headquarters in 2003 and again in 2008. The latter produced a report in which antineutrino detection was called a 'highly promising technology for safeguards applications' at nuclear reactors and several near-term goals and suggested developments were identified to facilitate wider applicability. Over the last few years, we have been working to achieve some of these goals and improvements. Specifically, we have already demonstrated the successful operation of non-toxic detectors and most recently, we are testing a transportable, above-ground detector system, which is fully contained within a standard 6 meter ISO container. If successful, such a system could allow easy deployment at any reactor facility around the world. As well, our previously demonstrated ability to remotely monitor the data and respond in real-time to reactor operational changes could allow the verification of operator declarations without the need for costly site-visits. As the global nuclear power industry expands around the world, the burden on maintaining operational histories and safeguarding inventories will increase greatly. Such a system for providing remote data to verify operator's declarations could greatly reduce the need for frequent site inspections while still providing a robust warning of anomalies requiring further investigation.

  11. Remote safeguards and monitoring of reactors with antineutrinos.

    Energy Technology Data Exchange (ETDEWEB)

    Kiff, Scott D.; Dazeley, Steven (Lawrence Livermore National Laboratory, Livermore, CA); Reyna, David; Cabrera-Palmer, Belkis; Bernstein, Adam (Lawrence Livermore National Laboratory, Livermore, CA); Keefer, Greg (Lawrence Livermore National Laboratory, Livermore, CA); Bowden, Nathaniel S. (Lawrence Livermore National Laboratory, Livermore, CA)

    2010-09-01

    The current state-of-the-art in antineutrino detection is such that it is now possible to remotely monitor the operational status, power levels and fissile content of nuclear reactors in real-time. This non-invasive and incorruptible technique has been demonstrated at civilian power reactors in both Russia and the United States and has been of interest to the IAEA Novel Technologies Unit for several years. Expert's meetings were convened at IAEA headquarters in 2003 and again in 2008. The latter produced a report in which antineutrino detection was called a 'highly promising technology for safeguards applications' at nuclear reactors and several near-term goals and suggested developments were identified to facilitate wider applicability. Over the last few years, we have been working to achieve some of these goals and improvements. Specifically, we have already demonstrated the successful operation of non-toxic detectors and most recently, we are testing a transportable, above-ground detector system, which is fully contained within a standard 6 meter ISO container. If successful, such a system could allow easy deployment at any reactor facility around the world. As well, our previously demonstrated ability to remotely monitor the data and respond in real-time to reactor operational changes could allow the verification of operator declarations without the need for costly site-visits. As the global nuclear power industry expands around the world, the burden on maintaining operational histories and safeguarding inventories will increase greatly. Such a system for providing remote data to verify operator's declarations could greatly reduce the need for frequent site inspections while still providing a robust warning of anomalies requiring further investigation.

  12. Above-ground antineutrino detection for nuclear reactor monitoring

    International Nuclear Information System (INIS)

    Antineutrino monitoring of nuclear reactors has been demonstrated many times (Klimov et al., 1994 [1]; Bowden et al., 2009 [2]; Oguri et al., 2014 [3]), however the technique has not as of yet been developed into a useful capability for treaty verification purposes. The most notable drawback is the current requirement that detectors be deployed underground, with at least several meters-water-equivalent of shielding from cosmic radiation. In addition, the deployment of liquid-based detection media presents a challenge in reactor facilities. We are currently developing a detector system that has the potential to operate above ground and circumvent deployment problems associated with a liquid detection media: the system is composed of segments of plastic scintillator surrounded by 6LiF/ZnS:Ag. ZnS:Ag is a radio-luminescent phosphor used to detect the neutron capture products of 6Li. Because of its long decay time compared to standard plastic scintillators, pulse-shape discrimination can be used to distinguish positron and neutron interactions resulting from the inverse beta decay (IBD) of antineutrinos within the detector volume, reducing both accidental and correlated backgrounds. Segmentation further reduces backgrounds by identifying the positron's annihilation gammas, a signature that is absent for most correlated and uncorrelated backgrounds. This work explores different configurations in order to maximize the size of the detector segments without reducing the intrinsic neutron detection efficiency. We believe that this technology will ultimately be applicable to potential safeguards scenarios such as those recently described by Huber et al. (2014) [4,5

  13. Above-ground antineutrino detection for nuclear reactor monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Sweany, M.; Brennan, J.; Cabrera-Palmer, B.; Kiff, S.; Reyna, D.; Throckmorton, D.

    2015-01-01

    Antineutrino monitoring of nuclear reactors has been demonstrated many times (Klimov et al., 1994 [1]; Bowden et al., 2009 [2]; Oguri et al., 2014 [3]), however the technique has not as of yet been developed into a useful capability for treaty verification purposes. The most notable drawback is the current requirement that detectors be deployed underground, with at least several meters-water-equivalent of shielding from cosmic radiation. In addition, the deployment of liquid-based detection media presents a challenge in reactor facilities. We are currently developing a detector system that has the potential to operate above ground and circumvent deployment problems associated with a liquid detection media: the system is composed of segments of plastic scintillator surrounded by {sup 6}LiF/ZnS:Ag. ZnS:Ag is a radio-luminescent phosphor used to detect the neutron capture products of {sup 6}Li. Because of its long decay time compared to standard plastic scintillators, pulse-shape discrimination can be used to distinguish positron and neutron interactions resulting from the inverse beta decay (IBD) of antineutrinos within the detector volume, reducing both accidental and correlated backgrounds. Segmentation further reduces backgrounds by identifying the positron's annihilation gammas, a signature that is absent for most correlated and uncorrelated backgrounds. This work explores different configurations in order to maximize the size of the detector segments without reducing the intrinsic neutron detection efficiency. We believe that this technology will ultimately be applicable to potential safeguards scenarios such as those recently described by Huber et al. (2014) [4,5].

  14. Present status of sensitive detector of reactor’s antineutrinos using scintillating detectors

    Energy Technology Data Exchange (ETDEWEB)

    Fajt, L.; Mamedov, F.; Přidal, P.; Špavorová, M.; Štekl, I. [Institute of Experimental and Applied Physics, CTU in Prague (Czech Republic); Belov, V.; Egorov, V. G.; Fomina, M.; Kuznetsov, A.; Ponomarev, D.; Rozova, I.; Zhitnikov, I. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Burešová, H. [ENVINET a.s., Nuvia Group, Tǐebíč (Czech Republic)

    2015-08-17

    In 2011, the reanalysis of the reactor antineutrinos spectra led to the formulation of the Reactor Antineutrino Anomaly (RAA) [1], which indicates the discrepancy between measured and expected antineutrino fluxes on short baselines. This discrepancy appears to favor the existence of the fourth “sterile” neutrino with |Δm{sup 2}|>1 eV{sup 2}. To confirm or reject this hypothesis a high sensitive antineutrino detector located close to the reactor is required. In addition to that such a detector could be used to online monitor the isotopic composition of the reactor core and to prevent illegal production and removal of{sup 239}Pu, which is the essential part of nuclear weapons. Detector DANSSino [2] already proved that even a compact antineutrino detector (∼ 1 m{sup 3}) based on polystyrene is capable of antineutrino detection in the close vicinity of a reactor core (∼ 10 m) with signal to background ratio about one. As a common activity between JINR Dubna and IEAP CTU a new prototype of detector (called S{sup 3}) has been proposed and is under construction. The construction design, selected results of Monte Carlo simulations and results of benchmark tests are presented.

  15. KamLAND Bounds on Solar Antineutrinos and neutrino transition magnetic moments

    CERN Document Server

    Torrente-Lujan, E

    2003-01-01

    We investigate the possibility of detecting solar antineutrinos with the KamLAND experiment. These antineutrinos are predicted by spin-flavor oscillations at a significant rate even if this mechanism is not the leading solution to the SNP. The recent evidence from SNO shows that the solar flux could contain a residual component including sterile neutrinos and/or the antineutrinos of the active flavors. KamLAND is sensitive to antineutrinos originated from solar ${}^8$B neutrinos. From KamLAND negative results after 145 days of data taking, we obtain model independent limits on the total flux of solar antineutrinos $\\Phi({}^8 B)< 1.1-3.5\\times 10^4 cm^{-2} s^{-1}$, more than one order of magnitude smaller than existing limits,and on their appearance probability $P<0.15%$ (95% CL). Assuming a concrete model for antineutrino production by spin-flavor precession, this upper bound implies an upper limit on the product of the intrinsic neutrino magnetic moment and the value of the solar magnetic field $\\mu B&...

  16. Search for electron antineutrinos associated with gravitational wave events GW150914 and GW151226 using KamLAND

    CERN Document Server

    Gando, A; Hachiya, T; Hayashi, A; Hayashida, S; Ikeda, H; Inoue, K; Ishidoshiro, K; Karino, Y; Koga, M; Matsuda, S; Mitsui, T; Nakamura, K; Obara, S; Oura, T; Ozaki, H; Shimizu, I; Shirahata, Y; Shirai, J; Suzuki, A; Takai, T; Tamae, K; Teraoka, Y; Ueshima, K; Watanabe, H; Kozolov, A; Takemoto, Y; Yoshida, S; Fushimi, K; Piepke, A; Banks, T I; Berger, B E; Fujikawa, B K; O'Donnell, T; Learned, J G; Maricic, J; Sakai, M; Winslow, L A; Krupczak, E; Ouellet, J; Efremenko, Y; Karwowski, H J; Markoff, D M; Tornow, W; Detwiler, J A; Enomoto, S; Decowski, M P

    2016-01-01

    We present a search for low energy antineutrino events coincident with the gravitational wave events GW150914 and GW151226, and the candidate event LVT151012 using KamLAND, a kiloton-scale antineutrino detector. We find no inverse beta-decay neutrino events within $\\pm 500$ seconds of either gravitational wave signal. This non-detection is used to constrain the electron antineutrino fluence and the luminosity of the astrophysical sources.

  17. A new anti-neutrino detection technique based on positronium tagging with plastic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Consolati, G. [Department of Aerospace Science and Technology, Politecnico di Milano, via La Masa 34, 20156 Milano (Italy); Franco, D., E-mail: dfranco@in2p3.fr [APC, Univ. Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs. de Paris, Sorbonne Paris Cité, 75205 Paris (France); Jollet, C. [IPHC, Université de Strasbourg, CNRS/IN2P3, 67037 Strasbourg (France); Meregaglia, A., E-mail: amerega@in2p3.fr [IPHC, Université de Strasbourg, CNRS/IN2P3, 67037 Strasbourg (France); Minotti, A. [IPHC, Université de Strasbourg, CNRS/IN2P3, 67037 Strasbourg (France); Perasso, S.; Tonazzo, A. [APC, Univ. Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs. de Paris, Sorbonne Paris Cité, 75205 Paris (France)

    2015-09-21

    The main signature for anti-neutrino detection in reactor and geo-neutrino experiments based on scintillators is provided by the space–time coincidence of positron and neutron produced in the Inverse Beta Decay reaction. Such a signature strongly suppresses backgrounds and allows for measurements performed underground with a relatively high signal-to-background ratio. In an aboveground environment, however, the twofold coincidence technique is not sufficient to efficiently reject the high background rate induced by cosmogenic events. Enhancing the positron–neutron twofold coincidence efficiency may pave the way to future aboveground detectors for reactor monitoring. We propose a new detection scheme based on a threefold coincidence, among the positron ionization, the ortho-positronium (o-Ps) decay, and the neutron capture, in a sandwich detector with alternated layers of plastic scintillator and aerogel powder. We present the results of a set of dedicated measurements on the achievable light yield and on the o-Ps formation and lifetime. The efficiencies for signal detection and background rejection of a preliminary detector design are also discussed.

  18. Effects of Recent Reactor Anti-neutrino Spectra on Neutrino Oscillations

    Science.gov (United States)

    Sterbenz, Ciara

    2015-10-01

    The β-decay of nuclear fission fragments produces a very large ve flux from nuclear reactions. The shape of the expected flux has previously been predicted by converting the measured β-electron spectrum to an ve spectrum. Recent reactor neutrino experiments, however, find a large shoulder in the observed ve spectrum relative to this prediction in the energy region 5 - 7 MeV. Accurate knowledge of the expected ve flux from reactors is important for oscillation experiments that only involve one neutrino detector. In this project, I examine the implications of these spectral changes on the ν oscillation result found by the KamLAND experiment. At the time of their finding, the spectral anomaly from 5 - 7 MeV had not be observed. I have re-derived the oscillation parameters Δm2 and sin2 (2 θ) using the anti-neutrino flux from Daya Bay and from nuclear database predictions. With these new expected fluxes, these oscillation parameters shifted and their uncertainties increased. I compare the new oscillation parameters with those derived from solar neutrino oscillation data.

  19. Gamow-Teller strength in deformed nuclei within the self-consistent charge-exchange quasi-particle random-phase approximation with the Gogny force

    CERN Document Server

    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.

  20. A comparison of empirical and experimental O7+, O8+, and O/H values, with applications to terrestrial solar wind charge exchange

    Science.gov (United States)

    Whittaker, Ian C.; Sembay, Steve

    2016-07-01

    Solar wind charge exchange occurs at Earth between the neutral planetary exosphere and highly charged ions of the solar wind. The main challenge in predicting the resultant photon flux in the X-ray energy bands is due to the interaction efficiency, known as the α value. This study produces experimental α values at the Earth, for oxygen emission in the range of 0.5-0.7 keV. Thirteen years of data from the Advanced Composition Explorer are examined, comparing O7+ and O8+ abundances, as well as O/H to other solar wind parameters allowing all parameters in the αO7,8+ calculation to be estimated based on solar wind velocity. Finally, a table is produced for a range of solar wind speeds giving average O7+ and O8+ abundances, O/H, and αO7,8+ values.

  1. Profile Measurement of Ion Temperature and Toroidal Rotation Velocity with Charge Exchange Recombination Spectroscopy Diagnostics in the HL-2A Tokamak

    Institute of Scientific and Technical Information of China (English)

    吴静; 姚列明; 朱建华; 韩晓玉; 李文柱

    2012-01-01

    This paper deals with the profile measurement of impurity ion temperature and toroidal rotation velocity that can be achieved by using the charge exchange recombination spectrum (CXRS) diagnostics tool built on the HL-2A toknmak. By using CXRS, an accurate impurity ion temperature and toroidal plasma rotation velocity profile can be achieved under the condition of neutrM beam injection (NBI) heating. Considering the edge effect of the line of CVI 529.06 nm (n= 8-7), which contains three lines (active exciting spectral line (ACX), passivity exciting spectral line (PCX) and electron exciting spectral line (ICE)), and using three Gaussian fitted curves, we obtain the following experimental results: the core ion temperature of HL-2A device is nearly thousands of eV, and the plasma rotation velocity reaches about 104 m· s^-1. At the end of paper, some explanations are presented for the relationship between the curves and the inner physical mechanism.

  2. Profile Measurement of Ion Temperature and Toroidal Rotation Velocity with Charge Exchange Recombination Spectroscopy Diagnostics in the HL-2A Tokamak

    Science.gov (United States)

    Wu, Jing; Yao, Lieming; Zhu, Jianhua; Han, Xiaoyu; Li, Wenzhu

    2012-11-01

    This paper deals with the profile measurement of impurity ion temperature and toroidal rotation velocity that can be achieved by using the charge exchange recombination spectrum (CXRS) diagnostics tool built on the HL-2A tokamak. By using CXRS, an accurate impurity ion temperature and toroidal plasma rotation velocity profile can be achieved under the condition of neutral beam injection (NBI) heating. Considering the edge effect of the line of CVI 529.06 nm (n = 8~7), which contains three lines (active exciting spectral line (ACX), passivity exciting spectral line (PCX) and electron exciting spectral line (ICE)), and using three Gaussian fitted curves, we obtain the following experimental results: the core ion temperature of HL-2A device is nearly thousands of eV, and the plasma rotation velocity reaches about 104 m · s-1. At the end of paper, some explanations are presented for the relationship between the curves and the inner physical mechanism.

  3. Measurement of deuterium density profiles in the H-mode steep gradient region using charge exchange recombination spectroscopy on DIII-D

    Science.gov (United States)

    Haskey, S. R.; Grierson, B. A.; Burrell, K. H.; Chrystal, C.; Groebner, R. J.; Kaplan, D. H.; Pablant, N. A.; Stagner, L.

    2016-11-01

    Recent completion of a thirty two channel main-ion (deuterium) charge exchange recombination spectroscopy (CER) diagnostic on the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] enables detailed comparisons between impurity and main-ion temperature, density, and toroidal rotation. In a H-mode DIII-D discharge, these new measurement capabilities are used to provide the deuterium density profile, demonstrate the importance of profile alignment between Thomson scattering and CER diagnostics, and aid in determining the electron temperature at the separatrix. Sixteen sightlines cover the core of the plasma and another sixteen are densely packed towards the plasma edge, providing high resolution measurements across the pedestal and steep gradient region in H-mode plasmas. Extracting useful physical quantities such as deuterium density is challenging due to multiple photoemission processes. These challenges are overcome using a detailed fitting model and by forward modeling the photoemission using the FIDASIM code, which implements a comprehensive collisional radiative model.

  4. The charge exchange process between C6+ and He+ ions: computation of cross sections and comparison with some data from fusion plasmas

    International Nuclear Information System (INIS)

    The total and partial cross sections for the capture process C6++He+→C5++He2+ are computed at impact energy in the range 0.1-40 keV amu-1 using the classical trajectory Monte Carlo (CTMC) method. Rate coefficients, which are used in practical applications, are estimated by assuming Maxwellian energy distributions for both incident and target ions, and are used to compute the intensity of the hydrogen-like carbon Lyman series lines in a fusion plasma. A comparison with the line ratios measured in a reversed field pinch device is made. It is shown that this charge exchange process is not likely to sensitively alter line ratios in helium fusion plasmas. (author)

  5. Coherent pion production in the 12C and 40Ca by the (3 He,tπ+) charge exchange reaction at 2 GeV

    International Nuclear Information System (INIS)

    The coherent pion production process on nuclei is defined as the excitation of the first excited state of the nucleon, the delta(1232) resonance, creating a delta-hole state. This state propagates through the nuclear medium and then decays in a single pion, living the target nuclei in its ground state. In the nuclei, the attractive interaction between delta-hole states in the spin-longitudinal channel shifts down the effective mass of the delta and induces a collective state of excitation. The nuclear response in the longitudinal channel of interaction can be studied experimentally through the resonance decay coherent process triggered by a probe coupling longitudinally with the delta and selected by the target form factor. The (3He, t) probe at 2 GeV on nuclei and the experimental set-up SPES IV-Pi have been used to study this decay process. A simulation program using GEANT and including theoretical consideration, knowledge of previous experimental results and the experimental properties of the set-up, have demonstrated the capability of the experiment for this study. The setting of the PCOS-IV acquisition system of multiwire proportional chambers and of the development and use of programs for treatment and analysis of experimental data have been necessary steps to make the experiment at Laboratoire National SATURNE as well as to obtain physical parameters in order to exhibit the coherent process. Nevertheless, the angular distribution of coherent pions differ from the theoretical predictions. Several hypotheses involving the experimental set-up and physical processes have been investigated in order to account for such distributions. (author)

  6. Measurement of charm production in antineutrino charged-current interactions

    CERN Document Server

    Onengüt, G; De Jong, M; Konijn, J; Melzer, O; Oldeman, R G C; Pesen, E; Van der Poel, C A F J; Visschers, J L; Güler, M; Köse, U; Serin-Zeyrek, M; Kama, S; Sever, R; Tolun, P; Zeyrek, M T; Catanesi, M G; De Serio, M; Ieva, M; Muciaccia, M T; Radicioni, E; Simone, S; Bülte, A; Winter, Klaus; Van de Vyver, B; Vilain, P; Wilquet, G; Saitta, B; Di Capua, E; Ogawa, S; Shibuya, H; Artamonov, A V; Brunner, J; Chizhov, M; Cussans, D G; Doucet, M; Fabre, Jean-Paul; Hristova, I R; Kawamura, T; Kolev, D; Litmaath, M; Meinhard, H; Panman, J; Papadopoulos, I M; Ricciardi, S; Rozanov, A; Saltzberg, D; Tsenov, R V; Uiterwijk, J W E; Zucchelli, P; Goldberg, J; Chikawa, M; Arik, E; Song, J S; Yoon, C S; Kodama, K; Ushida, N; Aoki, S; Hara, T; Delbar, T; Favart, D; Grégoire, G; Kalinin, S; Makhlyoueva, I V; Gorbunov, P; Khovanskii, V D; Shamanov, V V; Tsukerman, I; Bruski, N; Frekers, D; Rondeshagen, D; Wolff, T; Hoshino, K; Kawada, J; Komatsu, M; Miyanishi, M; Nakamura, M; Nakano, T; Narita, K; Niu, K; Niwa, K; Nonaka, N; Sato, O; Toshito, T; Buontempo, S; Cocco, A G; D'Ambrosio, N; De Lellis, G; De Rosa, G; Di Capua, F; Ereditato, A; Fiorillo, G; Marotta, A; Messina, M; Migliozzi, P; Pistillo, C; Santorelli, R; Scotto-Lavina, L; Strolin, P; Tioukov, V; Nakamura, K; Okusawa, T; Dore, U; FLoverre, P; Ludovici, L; Maslennikov, A L; Righini, P; Rosa, G; Santacesaria, R; Satta, A; Spada, F R; Barbuto, E; Bozza, C; Grella, G; Romano, G; Sirignano, C; Sorrentino, S; Sato, Y; Tezuka, I

    2004-01-01

    During the years 1994-97, the emulsion target of the CHORUS detector was exposed to the wideband neutrino beam of the CERN SPS collecting about 10^6 neutrino interactions. A measurement of nubar_mu-induced charm production is performed by usingthe presence of a 5% nubarmu component in the nu_mu beam. The measurement takes advantage of the capability to observe the decay topology in the emulsion. The analysis is based on a sample of charged-current interactions with at least one identified muon. About 100 000 vere located in the emulsion target and fully reconstructed. By requiring a positive muon charge as determined by the CHORUS spectrometer, 32-nubar_mu induced charm events were observed with an estimated background of 3.2 events. At an average antineutrino energy in the neutrino beam of 18GeV, the charm production rate induced by anitneutrinos is measured to be sigma(nubar_muN -> mu+cbarX)/sigma(nubar_muN -> mu+X) = (5.0^+1.4_-0.9(stat) +- 0.7(syst))%. The ratio between neutral and charged charm productio...

  7. Towards Earth AntineutRino TomograpHy (EARTH)

    CERN Document Server

    De Meijer, R J; Fearick, R W; Mantovani, F; Smit, F D; Wörtche, H J

    2006-01-01

    The programme Earth AntineutRino TomograpHy (EARTH) proposes to build ten underground facilities each hosting a telescope. Each telescope consists of many detector modules, to map the radiogenic heat sources deep in the interior of the Earth by utilising direction sensitive geoneutrino detection. Recent hypotheses target the core-mantle boundary (CMB) as a major source of natural radionuclides and therefore of radiogenic heat. A typical scale of the processes that take place at the CMB is about 200km. To observe these processes from the surface requires an angular resolution of about 3 degrees. EARTH aims at creating a high-resolution 3D-map of the radiogenic heat sources in the interior of the Earth. It will thereby contribute to a better understanding of a number of geophysical phenomena observed at the surface of the Earth. This condition requires a completely different approach from the monolithic detector systems as e.g. KamLAND. This paper presents, for such telescopes, the boundary conditions set by ph...

  8. Improved Measurement of Electron Antineutrino Disappearance at Daya Bay (Proceeding to NuFact12)

    CERN Document Server

    Qian, Xin

    2012-01-01

    The Daya Bay experiment was designed to be the largest and the deepest underground among the many current-generation reactor antineutrino experiments. With functionally identical detectors deployed at multiple baselines, the experiment aims to achieve the most precise measurement of $\\sin^2 2\\theta_{13}$. The antineutrino rates measured in the two near experimental halls are used to predict the rate at the far experimental hall (average distance of 1648 m from the reactors), assuming there is no neutrino oscillation. The ratio of the measured over the predicted far-hall antineutrino rate is then used to constrain the $\\sin^2 2\\theta_{13}$. The relative systematic uncertainty on this ratio is expected to be 0.2$\\sim$0.4%. In this talk, we present an improved measurement of the electron antineutrino disappearance at Daya Bay. With data of 139 days, the deficit of the antineutrino rate in the far experimental hall was measured to be 0.056 $\\pm$ 0.007 (stat.) $\\pm$ 0.003 (sys.). In the standard three-neutrino fra...

  9. Experimental determination of the antineutrino spectrum of the fission products of U238

    International Nuclear Information System (INIS)

    Accurate predictions of the antineutrino spectrum emitted by a nuclear reactor are of paramount importance for current and future reactor neutrino experiments. The antineutrinos are produced in the β - decays of the fission daughters of the four main fuel isotopes 235U, 238U, 239Pu, and 241Pu. One way to calculate the total anti νe - spectrum emitted by a fuel assembly is to experimentally determine the cumulative β-spectra emitted after fission of these four main fuel isotopes and to convert these into the corresponding anti νe-spectra. Three of the four spectra could already be determined in the 1980's, but only recently an experiment at the scientific neutron source FRM II in Garching could be performed to measure the anti νe-spectrum of 238U which contributes 10 % to the total antineutrino output of a standard PWR. With this spectrum, it is now possible to predict the antineutrino output of a reactor without the use of theoretical calculations for the contributing spectra. This talk describes the results of the experiment and discusses the impact on the current analysis of reactor neutrino experiments and the reactor antineutrino anomaly, which may give a hint on the possible existence of light sterile neutrinos.

  10. A search for low-energy neutrino and antineutrino signals correlated with gamma-ray bursts with Borexino

    CERN Document Server

    Agostini, M; Appel, S; Atroshchenko, V; Bellini, G; Benziger, J; Bick, D; Bonfini, G; Bravo, D; Caccianiga, B; Calaprice, F; Caminata, A; Carlini, M; Cavalcante, P; Chepurnov, A; Choi, K; D'Angelo, D; Davini, S; de Kerret, H; Derbin, A; Di Noto, L; Drachnev, I; Etenko, A; Fomenko, K; Franco, D; Gabriele, F; Galbiati, C; Ghiano, C; Giammarchi, M; Goeger-Neff, M; Goretti, A; Gromov, M; Hagner, C; Hungerford, E; Ianni, Aldo; Ianni, Andrea; Jany, A; Jedrzejczak, K; Jeschke, D; Kobychev, V; Korablev, D; Korga, G; Kryn, D; Laubenstein, M; Lehnert, B; Litvinovich, E; Lombardi, F; Lombardi, P; Ludhova, L; Lukyanchenko, G; Machulin, I; Manecki, S; Maneschg, W; Manuzio, G; Marcocci, S; Meroni, E; Meyer, M; Miramonti, L; Misiaszek, M; Montuschi, M; Mosteiro, P; Muratova, V; Neumair, B; Oberauer, L; Obolensky, M; Ortica, F; Pallavicini, M; Papp, L; Pocar, A; Ranucci, G; Razeto, A; Re, A; Romani, A; Roncin, R; Rossi, N; Scheonert, S; Semenov, D; Skorokhvatov, M; Smirnov, O; Sotnikov, A; Sukhotin, S; Suvorov, Y; Tartaglia, R; Testera, G; Thurn, J; Toropova, M; Unzhakov, E; Vishneva, A; Vogelaar, R B; von Feilitzsch, F; Wang, H; Weinz, S; Winter, J; Wojcik, M; Wurm, M; Yokley, Z; Zaimidoroga, O; Zavatarelli, S; Zuber, K; Zuzel, G

    2016-01-01

    A search for neutrino and antineutrino events correlated with 2,350 gamma-ray bursts (GRBs) is performed with Borexino data collected between December 2007 and November 2015. No statistically significant excess over background is observed. We look for electron antineutrinos ($\\bar{\

  11. Neutrino Geophysics at Baksan (Part II): Possible Studies of Antineutrino- and Radiogenic Heat Sources in Earth Interior

    OpenAIRE

    Domogatsky, G.; Kopeikin, V.; Mikaelyan, L.; Sinev, V.

    2004-01-01

    Antineutrinos born inside the Earth (``geoneutrinos'') carry out information of fundamental importance for understanding of the origin and evolution of our planet. We show that Baksan Neutrino Observatory is one of the best sites for detection and analysis of geoneutrinos using large liquid scintillation spectrometer. Also we present a short story of concept of Earth as antineutrino source (1960 - 2004 yy)

  12. aCORN: A Measurement of the Beta-Antineutrino Correlation in Neutron Decay

    Science.gov (United States)

    Jones, Gordon

    2015-10-01

    The aCORN experiment has measured the electron-antineutrino angular correlation coefficient (the ``a'' coefficient) in free neutron decay. aCORN uses the dependence of the recoil proton momentum on the opening angle between the electron and the neutrino to form an asymmetry. The apparatus accepts decays where the antineutrino is restricted to two momentum groups having equal solid angle. In this geometry, proton time of flight distinguishes between decays with a large or small opening angle between the electron and the antineutrino. The correlation coefficient is determined from the asymmetry between two branches of the time of flight spectrum. The asymmetry was measured on the NG-6 neutron beam at the NIST Center for Neutron Research (NCNR), and a subsequent measurement has been started on the higher flux NG-C beam. An overview of the method and systematic effects will be presented, including results from the NG-6 dataset. National Science Foundation.

  13. Monitoring nuclear reactors with anti-neutrino detectors: the ANGRA project

    Energy Technology Data Exchange (ETDEWEB)

    Chimenti, Pietro; Leigui, Marcelo Augusto [UFABC - Universidade Federal do ABC. Rua Santa Adelia, 166. Bairro Bangu. Santo Andre - SP (Brazil); Anjos, Joao; Azzi, Gabriel; Rafael, Gama; Ademarlaudo, Barbosa; Lima, Herman; VAZ, Mario; Villar, Arthur [Centro Brasileiro de Pesquisas Fisicas - CBPF, Rua Dr. Xavier Sigaud, 150, Urca, Rio de Janeiro, RJ - 22290-180 (Brazil); Gonzales, Luis Fernando; Bezerra, Thiago; Kemp, Ernesto [Unicamp, State University of Campinas, Cidade Universitaria ' Zeferino Vaz' , Barao Geraldo - Campinas, Sao Paulo (Brazil); Nunokawa, Hiroshi [Department of Physics, Pontifical Catholic University - PUC, Rua Marques de Sao Vicente, 225, 22451-900 Gavea - Rio de Janeiro - RJ (Brazil); Guedes, Germano; Faria, Paulo Cesar [Universidade Estadual de Feira de Santana - UEFS, Avenida Transnordestina, Novo Horizonte (Brazil); Pepe, Iuri [Universidade Federal da Bahia - UFBA (Brazil)

    2010-07-01

    We describe the status of the ANGRA Project, aimed at developing an anti-neutrino detector for monitoring nuclear reactors. Indeed the detection of anti-neutrinos provides a unique handle for non-invasive measurements of the nuclear fuel. This kind of measurements are of deep interest for developing new safeguards tools which may help in nuclear non-proliferation programs. The ANGRA experiment, placed at about 30 m from the core of the 4 GW Brazilian nuclear power reactor ANGRA II, is based on a water Cherenkov detector with about one ton target mass. A few thousand antineutrino interactions per day are expected. The latest results from simulations and the status of the construction are presented. (authors)

  14. The Physics of antineutrinos in DUNE and resolution of octant degeneracy

    CERN Document Server

    Nath, Newton; Goswami, Srubabati

    2016-01-01

    We study the capability of the DUNE experiment, which will be the first beam based experiment with a wide band flux profile, to uncover the octant of the leptonic mixing angle $\\theta_{23}$ (i.e., $\\theta_{23}$ is $45^\\circ$). In this work, we find that for the DUNE baseline of 1300 km, due to enhanced matter effect, the neutrino and antineutrino probabilities are different which creates a tension in the case of combined runs because of which octant sensitivity also can come from disappearance channel. In view of this, we study the physics of antineutrinos in DUNE and explore the role of antineutrinos run that is required to resolve the octant degeneracy at a certain confidence levels.

  15. Search for the disappearance of muon antineutrinos in the NuMI neutrino beam

    CERN Document Server

    Adamson, P; Ayres, D S; Backhouse, C; Barr, G; Bishai, M; Blake, A; Bock, G J; Boehnlein, D J; Bogert, D; Cao, S V; Cavanaugh, S; Cherdack, D; Childress, S; Choudhary, B C; Coelho, J A B; Coleman, S J; Corwin, L; Cronin-Hennessy, D; Danko, I Z; de Jong, J K; Devenish, N E; Diwan, M V; Dorman, M; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Frohne, M V; Gallagher, H R; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grant, N; Grzelak, K; Habig, A; Hartnell, J; Hatcher, R; Himmel, A; Holin, A; Howcroft, C; Huang, X; Hylen, J; Irwin, G M; Isvan, Z; Jaffe, D E; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kopp, S; Kordosky, M; Kreymer, A; Lang, K; Lefeuvre, G; Ling, J; Litchfield, P J; Loiacono, L; Lucas, P; Mann, W A; Marshak, M L; Mathis, M; Mayer, N; Mehdiyev, R; Meier, J R; Messier, M D; Michael, D G; Miller, W H; Mishra, S R; Mitchell, J; Moore, C D; Mualem, L; Mufson, S; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; Ochoa-Ricoux, J P; Oliver, W P; Orchanian, M; Pahlka, R; Paley, J; Patterson, R B; Pawloski, G; Pearce, G F; Phan-Budd, S; Plunkett, R K; Qiu, X; Ratchford, J; Rebel, B; Rosenfeld, C; Rubin, H A; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Strait, M; Tagg, N; Talaga, R L; Tavera, M A; Thomas, J; Thomson, M A; Tinti, G; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Walding, J J; Weber, A; Webb, R C; White, C; Whitehead, L; Wojcicki, S G; Yang, T; Zwaska, R

    2011-01-01

    We report constraints on muon antineutrino oscillation parameters that were obtained by using the two MINOS detectors to measure the 7% antineutrino component of the NuMI neutrino beam. In the Far Detector, we select 130 events in the charged-current muon antineutrino sample, compared to a prediction of 136.4 +/- 11.7(stat) ^{+10.2}_{-8.9}(syst) events under the assumption |dm2bar|=2.32x10^-3 eV^2, snthetabar=1.0. A fit to the two-flavor oscillation approximation constrains |dm2bar|<3.37x10^-3 eV^2 at the 90% confidence level with snthetabar=1.0.

  16. Antineutrino emission and gamma background characteristics from a thermal research reactor

    CERN Document Server

    Bui, V M; Fallot, M; Communeau, V; Cormon, S; Estienne, M; Lenoir, M; Peuvrel, N; Shiba, T; Cucoanes, A S; Elnimr, M; Martino, J; Onillon, A; Porta, A; Pronost, G; Remoto, A; Thiolliere, N; Yermia, F; Zakari-Issoufou, A -A

    2016-01-01

    The detailed understanding of the antineutrino emission from research reactors is mandatory for any high sensitivity experiments either for fundamental or applied neutrino physics, as well as a good control of the gamma and neutron backgrounds induced by the reactor operation. In this article, the antineutrino emission associated to a thermal research reactor: the OSIRIS reactor located in Saclay, France, is computed in a first part. The calculation is performed with the summation method, which sums all the contributions of the beta decay branches of the fission products, coupled for the first time with a complete core model of the OSIRIS reactor core. The MCNP Utility for Reactor Evolution code was used, allowing to take into account the contributions of all beta decayers in-core. This calculation is representative of the isotopic contributions to the antineutrino flux which can be found at research reactors with a standard 19.75\\% enrichment in $^{235}$U. In addition, the required off-equilibrium correction...

  17. Reactor and Antineutrino Spectrum Calculations for the Double Chooz First Phase Results

    International Nuclear Information System (INIS)

    The Double Chooz reactor oscillation experiment is designed to search for a non-vanishing value of the mixing angle θ13. For the first phase of the experiment with only the far detector running, the reactor electron antineutrino flux is normalized via reactor simulation. For this first phase and from its last results, Double Chooz observed an evidence for a reactor electron antineutrino disappearance. In 227.93 days of far detector live time, we obtained sin22θ13=0.109±0.030(stat)±0.025(syst). This result excludes the no-oscillation hypothesis at 99.8% CL

  18. Precise measurement of neutrino and anti-neutrino differential cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Tzanov, M.; Naples, D.; Boyd, S.; McDonald, J.; Radescu, V.; Adams, T.; Alton, A.; Avvakumov, S.; deBarbaro, L.; deBarbaro, P.; Bernstein, R.H.; Bodek, A.; Bolton, T.; Brau, J.; Buchholz, D.; Budd, H.; Bugel, L.; Conrad, J.; Drucker, R.B.; Fleming, B.T.; Frey, R.; /Pittsburgh U. /Cincinnati U. /Columbia U. /Fermilab /Kansas State U. /Northwestern

    2005-09-01

    The NuTeV experiment at Fermilab has obtained a unique high statistics sample of neutrino and anti-neutrino interactions using its high-energy sign-selected beam. We present a measurement of the differential cross section for charged-current neutrino and anti-neutrino scattering from iron. Structure functions, F{sub 2}(x,Q{sup 2}) and xF{sub 3}(x,Q{sup 2}), are determined by fitting the inelasticity, y, dependence of the cross sections. This measurement has significantly improved systematic precision as a consequence of more precise understanding of hadron and muon energy scales.

  19. Antineutrino Background from Spent Fuel Storage in sensitive Searches for theta_13 at Reactors

    CERN Document Server

    Kopeikin, V; Sinev, V

    2004-01-01

    Sensitive searches for antineutrino oscillations in atmospheric mass parameter region much discussed in recent years are based on accurate comparison of the inverse beta decay positron spectra measured in two (or more) detectors, far and near, stationed e.g. at ~1000 m and ~100 m from the reactor(s). We show that antineutrinos emitted from the stored irradiated fuel can differently distort the soft part of positron spectra measured in the far and near detector and thus mimic (or hide) the oscillation signal

  20. Antineutrino Background from Spent Fuel Storage in sensitive Searches for theta_13 at Reactors

    OpenAIRE

    Kopeikin, V.; Mikaelyan, L.; Sinev, V.

    2004-01-01

    Sensitive searches for antineutrino oscillations in atmospheric mass parameter region much discussed in recent years are based on accurate comparison of the inverse beta decay positron spectra measured in two (or more) detectors, far and near, stationed e.g. at ~1000 m and ~100 m from the reactor(s). We show that antineutrinos emitted from the stored irradiated fuel can differently distort the soft part of positron spectra measured in the far and near detector and thus mimic (or hide) the osc...

  1. Two Particle-Hole Excitations in Charged Current Quasielastic Antineutrino--Nucleus Scattering

    CERN Document Server

    Nieves, J; Vacas, M J Vicente

    2013-01-01

    We evaluate the quasielastic and multinucleon contributions to the antineutrino nucleus scattering cross section and compare our results with the recent MiniBooNE data. We use a local Fermi gas model that includes RPA correlations and gets the multinucleon part from a systematic many body expansion of the $W$ boson selfenergy in the nuclear medium. The same model had been quite successful for the neutrino cross section and contains no new parameters. We have also analysed the relevance of 2p2h events for the antineutrino energy reconstruction.

  2. Two particle–hole excitations in charged current quasielastic antineutrino-nucleus scattering

    Energy Technology Data Exchange (ETDEWEB)

    Nieves, J., E-mail: jmnieves@ific.uv.es [Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia–CSIC, Institutos de Investigación de Paterna, E-46071 Valencia (Spain); Ruiz Simo, I. [Dipartimento di Fisica, Università di Trento, I-38123 Trento (Italy); Vicente Vacas, M.J. [Departamento de Física Teórica and IFIC, Centro Mixto Universidad de Valencia–CSIC, Institutos de Investigación de Paterna, E-46071 Valencia (Spain)

    2013-04-10

    We evaluate the quasielastic and multinucleon contributions to the antineutrino-nucleus scattering cross section and compare our results with the recent MiniBooNE data. We use a local Fermi gas model that includes RPA correlations and gets the multinucleon part from a systematic many body expansion of the W boson selfenergy in the nuclear medium. The same model had been quite successful for the neutrino cross section and contains no new parameters. We have also analyzed the relevance of 2p2h events for the antineutrino energy reconstruction.

  3. Nuclear effect study on nucleon structure functions, in comparison with antineutrino interactions on neon and deuterium

    International Nuclear Information System (INIS)

    We have studied the nuclear effects on high energy antineutrino charged current interactions by comparing the data which were taken in the Bubble Chamber BEBC filled with Neon and Deuterium. On the one hand, the study of nuclear reinteractions gave us the possibility to estimate the formation time of hadrons. On the other hand, the comparison of structure functions does not show any significant difference between Neon and Deuterium. Though this result does not contradict the effects observed with charged leptons by the EMC and SLAC experiments, it is strongly incompatible with certain theoretical interpretations which implied a stronger effect in antineutrino interactions

  4. Search for Lorentz invariance and CPT violation with muon antineutrinos in the MINOS Near Detector

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); et al.

    2012-02-01

    We have searched for sidereal variations in the rate of antineutrino interactions in the MINOS Near Detector. Using antineutrinos produced by the NuMI beam, we find no statistically significant sidereal modulation in the rate. When this result is placed in the context of the Standard Model Extension theory we are able to place upper limits on the coefficients defining the theory. These limits are used in combination with the results from an earlier analysis of MINOS neutrino data to further constrain the coefficients.

  5. Search for differences in oscillation parameters for atmospheric neutrinos and antineutrinos at Super-Kamiokande

    OpenAIRE

    Abe, K.; Labarga, L.; Magro, L. M.; Super-Kamiokande Collaboration, .

    2011-01-01

    Artículo escrito por muchos autores, sólo se referencian el primero, los autores que firman como Universidad Autónoma de Madrid y el grupo de colaboración en el caso de que aparezca en el artículo We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a differ...

  6. Final Report for Monitoring of Reactor Antineutrinos with Compact Germanium Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Orrell, John L.; Collar, J. I.

    2009-07-01

    This 2008 NCMR project has pursued measurement of the antineutrino-nucleus coherent scattering interaction using a low-energy threshold germanium gamma-ray spectrometer of roughly one-half kilogram total mass. These efforts support development of a compact system for monitoring the antineutrino emission from nuclear reactor cores. Such a monitoring system is relevant to nuclear safeguards and nuclear non-proliferation in general by adding a strong method for assuring quantitative material balance of special nuclear material in the nuclear fuel cycle used in electricity generation.

  7. Large scale Gd-beta-diketonate based organic liquid scintillator production for antineutrino detection

    CERN Document Server

    Aberle, C; Gramlich, B; Hartmann, F X; Lindner, M; Schönert, S; Schwan, U; Wagner, S; Watanabe, H

    2011-01-01

    Over the course of several decades organic liquid scintillators form the basis for successful neutrino detectors. For electron antineutrino detection at nuclear reactor plants, gadolinium loaded liquid scintillators provide efficient background suppression. In the Double Chooz reactor antineutrino experiment a newly developed gadolinium-loaded scintillator is utilized for the first time. Its large scale production and characterization as well as the creation of an additional metalfree scintillator are presented. Both organic liquids are used in the inner part of the Double Chooz detectors.

  8. First Test of Lorentz Violation with a Reactor-based Antineutrino Experiment

    CERN Document Server

    Abe, Y; Anjos, J C dos; Bergevin, M; Bernstein, A; Bezerra, T J C; Bezrukhov, L; Blucher, E; Bowden, N S; Buck, C; Busenitz, J; Cabrera, A; Caden, E; Camilleri, L; Carr, R; Cerrada, M; Chang, P -J; Chimenti, P; Classen, T; Collin, A P; Conover, E; Conrad, J M; Crespo-Anadón, J I; Crum, K; Cucoanes, A; D'Agostino, M V; Damon, E; Dawson, J V; Dazeley, S; Dietrich, D; Djurcic, Z; Dracos, M; Durand, V; Ebert, J; Efremenko, Y; Elnimr, M; Erickson, A; Fallot, M; Fechner, M; von Feilitzsch, F; Felde, J; Fischer, V; Franco, D; Franke, A J; Franke, M; Furuta, H; Gama, R; Gil-Botella, I; Giot, L; Göger-Neff, M; Gonzalez, L F G; Goodman, M C; Goon, J TM; Greiner, D; Haag, N; Habib, S; Hagner, C; Hara, T; Hartmann, F X; Haser, J; Hatzikoutelis, A; Hayakawa, T; Hofmann, M; Horton-Smith, G A; Ishitsuka, M; Jochum, J; Jollet, C; Jones, C L; Kaether, F; Kalousis, L N; Kamyshkov, Y; Kaplan, D M; Katori, T; Kawasaki, T; Keefer, G; Kemp, E; de Kerret, H; Konno, T; Kryn, D; Kuze, M; Lachenmaier, T; Lane, C E; Lasserre, T; Letourneau, A; Lhuillier, D; Lima, H P; Lindner, M; López-Castanõ, J M; LoSecco, J M; Lubsandorzhiev, B K; Lucht, S; McKee, D; Maeda, J; Maesano, C N; Mariani, C; Maricic, J; Martino, J; Matsubara, T; Mention, G; Meregaglia, A; Meyer, M; Miletic, T; Milincic, R; Miyata, H; Mueller, Th A; Nagasaka, Y; Nakajima, K; Novella, P; Obolensky, M; Oberauer, L; Onillon, A; Osborn, A; Ostrovskiy, I; Palomares, C; Pepe, I M; Perasso, S; Perrin, P; Pfahler, P; Porta, A; Potzel, W; Pronost, G; Reichenbacher, J; Reinhold, B; Remoto, A; Röhling, M; Roncin, R; Roth, S; Rybolt, B; Sakamoto, Y; Santorelli, R; Sato, F; Schönert, S; Schoppmann, S; Schwetz, T; Shaevitz, M H; Shrestha, D; Sida, J -L; Sinev, V; Skorokhvatov, M; Smith, E; Spitz, J; Stahl, A; Stancu, I; Stokes, L F F; Strait, M; Stüken, A; Suekane, F; Sukhotin, S; Sumiyoshi, T; Sun, Y; Terao, K; Tonazzo, A; Toups, M; Thi, H H Trinh; Valdiviesso, G; Veyssiere, C; Wagner, S; Watanabe, H; White, B; Wiebusch, C; Winslow, L; Worcester, M; Wurm, M; Yanovitch, E; Yermia, F; Zimmer, V

    2012-01-01

    We present a search for Lorentz violation with 8249 candidate electron antineutrino events taken by the Double Chooz experiment in 227.9 live days of running. This analysis, featuring a search for a sidereal time dependence of the events, is the first test of Lorentz invariance using a reactor-based antineutrino source. No sidereal variation is present in the data and the disappearance results are consistent with sidereal time independent oscillations. Under the Standard-Model Extension (SME), we set the first limits on fourteen Lorentz violating coefficients associated with transitions between electron and tau flavor, and set two competitive limits associated with transitions between electron and muon flavor.

  9. Precise Measurement of Neutrino and Anti-neutrino Differential Cross Sections

    CERN Document Server

    Tzanov, M; Boyd, S; McDonald, J; Radescu, V; Adams, T; Alton, A; Avvakumov, S; De Barbaro, L; De Barbaro, P; Bernstein, R H; Bodek, A; Bolton, T; Brau, J E; Buchholz, D; Budd, H; Bugel, L; Conrad, J; Drucker, R B; Fleming, B T; Frey, R; Formaggio, J A; Goldman, J; Goncharov, M; Harris, D A; Johnson, R A; Kim, J H; Koutsoliotas, S; Lamm, M J; Marsh, W; Mason, D; McFarland, K S; McNulty, C; Nienaber, P; Romosan, A; Sakumoto, W K; Schellman, H; Shaevitz, M H; Spentzouris, P; Stern, E G; Suwonjandee, N; Tobien, N; Vakili, M; Vaitaitis, A; Yang, U K; Yu, J; Zeller, G P; Zimmerman, E D

    2006-01-01

    The NuTeV experiment at Fermilab has obtained a unique high statistics sample of neutrino and anti-neutrino interactions using its high-energy sign-selected beam. We present a measurement of the differential cross section for charged-current neutrino and anti-neutrino scattering from iron. Structure functions, F_2(x,Q^2) and xF_3(x,Q^2), are determined by fitting the inelasticity, y, dependence of the cross sections. This measurement has significantly improved systematic precision as a consequence of more precise understanding of hadron and muon energy scales.

  10. Experimental Determination of the Antineutrino Spectrum of the Fission Products of $^{238}$U

    CERN Document Server

    Haag, N; Hofmann, M; Oberauer, L; Potzel, W; Schreckenbach, K; Wagner, F M

    2013-01-01

    An experiment was performed at the scientific neutron source FRM II in Garching to determine the cumulative antineutrino spectrum of the fission products of $^{238}$U. This was achieved by irradiating target foils of natural uranium with a thermal and a fast neutron beam and recording the emitted $\\beta$-spectra with a gamma-suppressing electron-telescope. The obtained $\\beta$-spectrum of the fission products of $^{235}$U was normalized to the data of the magnetic spectrometer BILL of $^{235}$U. This method strongly reduces systematic errors in the $^{238}$U measurement. The $\\beta$-spectrum of $^{238}$U was converted into the corresponding antineutrino spectrum. The final $\\bar\

  11. A Experiment to Determine the Mass of the Electron Antineutrino.

    Science.gov (United States)

    Sur, Bhaskar

    The fact that neutrinos may have mass has attracted considerable attention in recent years both on the theoretical and experimental forefronts. The advent of Grand Unified Theories, the candidacy of neutrinos as dark matter, the proposed neutrino oscillation (and MSW effect) solution to the Solar Neutrino Puzzle and the observance of neutrinos from Supernova 1987A have further stimulated experimental efforts to directly probe neutrino masses by looking for dynamical effects. The technique of examining the end -point spectrum of Tritium beta-decay has long been used in this vein. The recent report of a positive electron antineutrino mass of 30 +/- 2 ev by the ITEP group in Moscow and the subsequent results from Los Alamos, Zurich and Japan which are in conflict with this value have stirred some controversy in this field. The present experiment uses a technique which is different from the usual magnetic-electrostatic analysis of the beta-spectrum employed by most groups--that of sperical electrostatic retarding field analysis. This method yields an integrated spectrum of the source and because of this and the large solid angle of acceptance of the spectrometer, the experiment yields very good statistics. Also the proposed source in this case is frozen T_2 for which the various correction factors can be estimated very accurately. The design, construction and testing of the spectrometer is described in detail in this dissertation as is the procedure used for fitting the data and calculating the correction factors to be applied to it. Due to a series of unfortunate accidents, the experiment has not yet been completed, but having proved that the intrinsic (point source) resolution is only 5 to 10 ev, the total efficiency about 2% and the background count rate about 20 counts per second, the experiment is expected to yield a mass limit of the order of 20 ev when run with a source of strength of about 30 milliCurie for a few days in the very near future.

  12. On Lunar Exospheric Column Densities and Solar Wind Access Beyond the Terminator from ROSAT Soft X-Ray Observations of Solar Wind Charge Exchange

    Science.gov (United States)

    Collier, Michael R.; Snowden, S. L.; Sarantos, M.; Benna, M.; Carter, J. A.; Cravens, T. E.; Farrell, W. M.; Fatemi, S.; Hills, H. Kent; Hodges, R. R.; Holmstrom, M.; Kuntz, K. D.; Porter, F. Scott; Read, A.; Robertson, I. P.; Sembay, S. F.; Sibeck, D. G.; Stubbs, T. J.; Travnicek, P.; Walsh, B. M.

    2014-01-01

    We analyze the Rontgen satellite (ROSAT) position sensitive proportional counter soft X-ray image of the Moon taken on 29 June 1990 by examining the radial profile of the surface brightness in three wedges: two 19 deg wedges (one north and one south) 13-32 deg off the terminator toward the dark side and one wedge 38 deg wide centered on the antisolar direction. The radial profiles of both the north and the south wedges show significant limb brightening that is absent in the 38 deg wide antisolar wedge. An analysis of the soft X-ray intensity increase associated with the limb brightening shows that its magnitude is consistent with that expected due to solar wind charge exchange (SWCX) with the tenuous lunar atmosphere based on lunar exospheric models and hybrid simulation results of solar wind access beyond the terminator. Soft X-ray imaging thus can independently infer the total lunar limb column density including all species, a property that before now has not been measured, and provide a large-scale picture of the solar wind-lunar interaction. Because the SWCX signal appears to be dominated by exospheric species arising from solar wind implantation, this technique can also determine how the exosphere varies with solar wind conditions. Now, along with Mars, Venus, and Earth, the Moon represents another solar system body at which SWCX has been observed.

  13. Dissociation dynamics of highly excited molecules produced by charge exchange: Two-body dynamics of CH5 and three-body dynamics of sym-triazine

    International Nuclear Information System (INIS)

    Translational spectroscopy and coincidence detection of the neutral photofragments have been used to observe the dissociation dynamics of highly excited neutrals produced by charge exchange between keV cation beams with Cs, and the results from two novel systems are presented. CH5 is formed slightly above the 3s Rydberg level and dissociates into two possible fragmentation channels, H loss and H2 loss. The kinetic energy release distributions of the two products are presented and the branching ratio between the two is found to be 11.4 ± 1.5 : 1 with the H loss being the dominant channel. Production of the highly symmetric azabenzene sym-triazine in its 3s Rydberg state has been shown to induce dissociation to 3 HCN(Σ+). Examination of momentum correlation in the dissociation products shows that this dissociation occurs by two distinct mechanisms. Evidence from Monte Carlo simulations suggest a sequential mechanism occurs creating products accompanied by a kinetic energy release of ∼1.5-5 eV. A symmetric concerted mechanism is also observed and is associated with products receiving a 2-4 eV kinetic energy release.

  14. Neutrino nucleus reactions within the GiBUU model

    CERN Document Server

    Lalakulich, O; Mosel, U

    2011-01-01

    The GiBUU model, which implements all reaction channels relevant at medium neutrino energy, is used to investigate the neutrino and antineutrino scattering on iron. Results for integrated cross sections are compared with NOMAD and MINOS data. It is shown, that final state interaction can noticeably change the spectra of the outgoing hadrons. Predictions for the Miner$\

  15. Neutrino and antineutrino inclusive charged-current cross section measurement with the MINOS near detector

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Debdatta [Univ. of Pittsburgh, PA (United States)

    2009-01-01

    This thesis presents the measurement of energy dependence of the neutrino-nucleon inclusive charged current cross section on an isoscalar target in the range 3-50 GeV for neutrinos and 5-50 GeV energy range for antineutrinos. The data set was collected with the MINOS Near Detector using the wide band NuMI beam at Fermilab. The size of the charged current sample is 1.94 x 106 neutrino events and 1.60 x 105 antineutrino events. The flux has been extracted using a low hadronic energy sub-sample of the charged current events. The energy dependence of the cross section is obtained by dividing the charged current sample with the extracted flux. The neutrino and antineutrino cross section exhibits a linear dependence on energy at high energy but shows deviations from linear behavior at low energy. We also present a measurement of the ratio of antineutrino to neutrino inclusive cross section.

  16. Search for time-independent Lorentz violation using muon neutrino to muon antineutrino transitions in MINOS

    CERN Document Server

    Adamson, P; Aurisano, A; Barr, G; Bishai, M; Blake, A; Bock, G J; Bogert, D; Cao, S V; Carroll, T J; Castromonte, C M; Chen, R; Childress, S; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; de Jong, J K; de Rijck, S; Devan, A V; Devenish, N E; Diwan, M V; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Flanagan, W; Frohne, M V; Gabrielyan, M; Gallagher, H R; Germani, S; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grzelak, K; Habig, A; Hahn, S R; Hartnell, J; Hatcher, R; Holin, A; Huang, J; Hylen, J; Irwin, G M; Isvan, Z; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kordosky, M; Kreymer, A; Lang, K; Ling, J; Litchfield, P J; Lucas, P; Mann, W A; Marshak, M L; Mayer, N; McGivern, C; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Miller, W H; Mishra, S R; Sher, S Moed; Moore, C D; Mualem, L; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; O'Connor, J; Orchanian, M; Pahlka, R B; Paley, J; Patterson, R B; Pawloski, G; Perch, A; Pfützner, M M; Phan, D D; Phan-Budd, S; Plunkett, R K; Poonthottathil, N; Qiu, X; Radovic, A; Rebel, B; Rosenfeld, C; Rubin, H A; Sail, P; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Tian, X; Timmons, A; Todd, J; Tognini, S C; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Weber, A; Webb, R C; White, C; Whitehead, L; Whitehead, L H; Wojcicki, S G; Zwaska, R

    2016-01-01

    Data from the MINOS experiment has been used to search for mixing between muon neutrinos and muon antineutrinos using a time-independent Lorentz-violating formalism derived from the Standard-Model Extension (SME). MINOS is uniquely capable of searching for muon neutrino-antineutrino mixing given its long baseline and ability to distinguish between neutrinos and antineutrinos on an event-by-event basis. Neutrino and antineutrino interactions were observed in the MINOS Near and Far Detectors from an exposure of 10.56$\\times10^{20}$ protons-on-target from the NuMI neutrino-optimized beam. No evidence was found for such transitions and new, highly stringent limits were placed on the SME coefficients governing them. We place the first limits on the SME parameters $(c_{L})^{TT}_{\\mu\\mu} $ and $(c_{L})^{TT}_{\\tau\\tau}$ at $-8.4\\times10^{-23} < (c_{L})^{TT}_{\\mu\\mu} < 8.0\\times10^{-23}$ and $-8.0\\times10^{-23} < (c_{L})^{TT}_{\\tau\\tau} < 8.4\\times10^{-23}$, and the world's best limits on the $\\tilde{g}^{Z...

  17. Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Butorov, I; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J H; Cheng, J; Cheng, Y P; Cherwinka, J J; Chu, M C; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dove, J; Draeger, E; Dwyer, D A; Edwards, W R; Ely, S R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, X H; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, L M; Hu, L J; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lei, R T; Leitner, R; Leung, K Y; Leung, J K C; Lewis, C A; Li, D J; Li, F; Li, G S; Li, Q J; Li, S C; Li, W D; Li, X N; Li, X Q; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, P Y; Lin, S K; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, H; Liu, J L; Liu, J C; Liu, S S; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Meng, Y; Mitchell, I; Kebwaro, J Monari; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, B; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Shao, B B; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Tsang, K V; Tull, C E; Tung, Y C; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, Q; Xia, D M; Xia, J K; Xia, X; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C G; Yang, L; Yang, M S; Yang, M T; Ye, M; Yeh, M; Young, B L; Yu, G Y; Yu, Z Y; Zang, S L; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, Y M; Zhang, Y X; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y F; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2015-01-01

    This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9~GW$_{th}$ nuclear reactors with six detectors deployed in two near (effective baselines 512~m and 561~m) and one far (1,579~m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296,721 and 41,589 inverse beta decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55 $\\pm$ 0.04) $\\times$ 10$^{-18}$~cm$^2$/GW/day or (5.92 $\\pm$ 0.14) $\\times$ 10$^{-43}$~cm$^2$/fission. This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is $0.946\\pm0.022$ ($0.991\\pm0.023$) relative to the flux predicted with the Huber+Mueller (ILL+Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2$\\sigma$ over the full energy range with a local significance of up to $\\sim$4$\\sigma$ between 4-6 MeV. A reactor antineutrino spectrum...

  18. Measurement of electron antineutrino oscillation based on 1230 days of operation of the Daya Bay experiment

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J -H; Cheng, J; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Chu, M C; Chukanov, A; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, X H; Guo, Z; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Huo, W; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Jones, D; Joshi, J; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J L; Liu, J C; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Lv, Z; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Malyshkin, Y; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Mitchell, I; Mooney, M; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevskiy, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Treskov, K; Tsang, K V; Tull, C E; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J Y; Xu, J L; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Y M; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    A measurement of electron antineutrino oscillation by the Daya Bay Reactor Neutrino Experiment is described in detail. Six 2.9-GW$_{\\rm th}$ nuclear power reactors of the Daya Bay and Ling Ao nuclear power facilities served as intense sources of $\\overline{\

  19. Improved Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J -H; Cheng, J; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Chu, M C; Chukanov, A; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Huo, W; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Joshi, J; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J L; Liu, J C; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Lv, Z; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Malyshkin, Y; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Mitchell, I; Mooney, M; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevskiy, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Treskov, K; Tsang, K V; Tull, C E; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J Y; Xu, J L; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Y M; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    A new measurement of the reactor antineutrino flux and energy spectrum by the Daya Bay reactor neutrino experiment is reported. The antineutrinos were generated by six 2.9 GW$_{\\mathrm{th}}$ nuclear reactors and detected by eight antineutrino detectors deployed in two near (510~m and 560~m flux-weighted baselines) and one far (1580~m flux-weighted baseline) underground experimental halls. With 621 days of data, more than 1.2 million inverse beta decay (IBD) candidates were detected. The IBD yield in the eight detectors was measured, and the ratio of measured to predicted flux was found to be $0.946\\pm0.020$ ($0.992\\pm0.021$) for the Huber+Mueller (ILL+Vogel) model. A 2.9 $\\sigma$ deviation was found in the measured IBD positron energy spectrum compared to the predictions. In particular, an excess of events in the region of 4-6~MeV was found in the measured spectrum, with a local significance of 4.4 $\\sigma$. A reactor antineutrino spectrum weighted by the IBD cross section is extracted for model-independent p...

  20. New Decay Data Sub-library for Calculation of Nuclear Reactors Antineutrino Spectra

    Science.gov (United States)

    Sonzogni, Alejandro; McCutchan, Elizabeth; Johnson, Timothy

    2015-10-01

    The ENDF/B-VII.1 decay data sub-library contains up-to-date decay properties for all known nuclides and can be used in a wide variety of applications such as decay heat, delayed nu-bar and astrophysics. We have recently completed an upgrade to the ENDF/B-VII.1 decay data sub-library in order to better calculate antineutrino spectra from fission of actinide nuclides. This sub-library has been used to identify the main contributors to the antineutrino spectra as well as to derive a systematic behavior of the energy integrated spectra similar to that of the beta-delayed neutron multiplicities. The main improvements have been the use of the TAGS data from Algora et al and Greenwood et al, as well as some of the single beta spectrum data from Rudstam et al to obtain beta minus level feedings. Additionally, we have calculated the antineutrino spectra for neutron energies higher than thermal, needed for highly-enriched uranium cores, such as the HFIR in ORNL that will be used in the PROSPECT experiment. These calculations are relevant since the high precision beta spectra which are used in many antineutrino calculations were measured at thermal energies. The impact of the fission yield data on these calculations will be discussed. This work was sponsored by the Office of Nuclear Physics, Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886.

  1. Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra and Decay Heat Calculations

    Science.gov (United States)

    Porta, A.; Zakari-Issoufou, A.-A.; Fallot, M.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Bui, V. M.; Cormon, S.; Estienne, M.; Agramunt, J.; Äystö, J.; Bowry, M.; Briz, J. A.; Caballero-Folch, R.; Cano-Ott, D.; Cucouanes, A.; Elomaa, V.-V.; Eronen, T.; Estévez, E.; Farrelly, G. F.; Garcia, A. R.; Gelletly, W.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Jordan, M. D.; Kankainen, A.; Karvonen, P.; Kolhinen, V. S.; Kondev, F. G.; Martinez, T.; Mendoza, E.; Molina, F.; Moore, I.; Perez-Cerdán, A. B.; Podolyák, Zs.; Penttilä, H.; Regan, P. H.; Reponen, M.; Rissanen, J.; Rubio, B.; Shiba, T.; Sonzogni, A. A.; Weber, C.

    2016-03-01

    Beta decay of fission products is at the origin of decay heat and antineutrino emission in nuclear reactors. Decay heat represents about 7% of the reactor power during operation and strongly impacts reactor safety. Reactor antineutrino detection is used in several fundamental neutrino physics experiments and it can also be used for reactor monitoring and non-proliferation purposes. 92,93Rb are two fission products of importance in reactor antineutrino spectra and decay heat, but their β-decay properties are not well known. New measurements of 92,93Rb β-decay properties have been performed at the IGISOL facility (Jyväskylä, Finland) using Total Absorption Spectroscopy (TAS). TAS is complementary to techniques based on Germanium detectors. It implies the use of a calorimeter to measure the total gamma intensity de-exciting each level in the daughter nucleus providing a direct measurement of the beta feeding. In these proceedings we present preliminary results for 93Rb, our measured beta feedings for 92Rb and we show the impact of these results on reactor antineutrino spectra and decay heat calculations.

  2. Reconstructing the direction of reactor antineutrinos via electron scattering in Gd-doped water Cherenkov detector

    Energy Technology Data Exchange (ETDEWEB)

    Hellfeld, D. [Texas A & M Univ., College Station, TX (United States); Dazeley, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bernstein, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Marianno, C. [Texas A & M Univ., College Station, TX (United States)

    2015-11-25

    The potential of elastic antineutrino-electron scattering (ν¯e + e → ν¯e + e) in a Gd-doped water Cherenkov detector to determine the direction of a nuclear reactor antineutrino flux was investigated using the recently proposed WATCHMAN antineutrino experiment as a baseline model. The expected scattering rate was determined assuming a 13 km standoff from a 3.758 GWt light water nuclear reactor. Background was estimated via independent simulations and by appropriately scaling published measurements from similar detectors. Many potential backgrounds were considered, including solar neutrinos, misidentified reactor-based inverse beta decay interactions, cosmogenic radionuclide and water-borne radon decays, and gamma rays from the photomultiplier tubes, detector walls, and surrounding rock. The detector response was modeled using a GEANT4-based simulation package. The results indicate that with the use of low radioactivity PMTs and sufficient fiducialization, water-borne radon and cosmogenic radionuclides pose the largest threats to sensitivity. The directional sensitivity was then analyzed as a function of radon contamination, detector depth, and detector size. Lastly, the results provide a list of theoretical conditions that, if satisfied in practice, would enable nuclear reactor antineutrino directionality in a Gd-doped water Cherenkov detector approximately 10 km from a large power reactor.

  3. The relativistic Green's function model in charged-current quasielastic neutrino and antineutrino scattering at MINER$\

    OpenAIRE

    Meucci, Andrea; Giusti, Carlotta

    2014-01-01

    The analysis of charged-current quasielastic neutrino and antineutrino-nucleus scattering cross sections requires relativistic theoretical descriptions also accounting for the role of final-state interactions. We compare the results of the relativistic Green's function model with the data recently published by the MINER$\

  4. Neutrino and antineutrino inclusive charged-current cross section measurement with the MINOS near detector

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Debdatta; /Pittsburgh U.

    2009-03-01

    This thesis presents the measurement of energy dependence of the neutrino-nucleon inclusive charged current cross section on an isoscalar target in the range 3-50 GeV for neutrinos and 5-50 GeV energy range for antineutrinos. The data set was collected with the MINOS Near Detector using the wide band NuMI beam at Fermilab. The size of the charged current sample is 1.94 x 10{sup 6} neutrino events and 1.60 x 10{sup 5} antineutrino events. The flux has been extracted using a low hadronic energy sub-sample of the charged current events. The energy dependence of the cross section is obtained by dividing the charged current sample with the extracted flux. The neutrino and antineutrino cross section exhibits a linear dependence on energy at high energy but shows deviations from linear behavior at low energy. We also present a measurement of the ratio of antineutrino to neutrino inclusive cross section.

  5. Determination of the Sensitivity of the Antineutrino Probe for Reactor Core Monitoring

    Science.gov (United States)

    Cormon, S.; Fallot, M.; Bui, V.-M.; Cucoanes, A.; Estienne, M.; Lenoir, M.; Onillon, A.; Shiba, T.; Yermia, F.; Zakari-Issoufou, A.-A.

    2014-06-01

    This paper presents a feasibility study of the use of the detection of reactor-antineutrinos (νbare) for non proliferation purpose. To proceed, we have started to study different reactor designs with our simulation tools. We use a package called MCNP Utility for Reactor Evolution (MURE), initially developed by CNRS/IN2P3 labs to study Generation IV reactors. The MURE package has been coupled to fission product beta decay nuclear databases for studying reactor antineutrino emission. This method is the only one able to predict the antineutrino emission from future reactor cores, which don't use the thermal fission of 235U, 239Pu and 241Pu. It is also the only way to include off-equilibrium effects, due to neutron captures and time evolution of the fission product concentrations during a reactor cycle. We will present here the first predictions of antineutrino energy spectra from innovative reactor designs (Generation IV reactors). We will then discuss a summary of our results of non-proliferation scenarios involving the latter reactor designs, taking into account reactor physics constraints.

  6. A new measurement of antineutrino oscillation with the full detector configuration at Daya Bay

    CERN Document Server

    An, F.P.; Band, H.R.; Bishai, M.; Blyth, S.; Butorov, I.; Cao, G.F.; Cao, J.; Cen, W.R.; Chan, Y.L.; Chang, J.F.; Chang, L.C.; Chang, Y.; Chen, H.S.; Chen, Q.Y.; Chen, S.M.; Chen, Y.X.; Chen, Y.; Cheng, J.H.; Cheng, J.; Cheng, Y.P.; Cherwinka, J.J.; Chu, M.C.; Cummings, J.P.; de Arcos, J.; Deng, Z.Y.; Ding, X.F.; Ding, Y.Y.; Diwan, M.V.; Draeger, E.; Dwyer, D.A.; Edwards, W.R.; Ely, S.R.; Gill, R.; Gonchar, M.; Gong, G.H.; Gong, H.; Grassi, M.; Gu, W.Q.; Guan, M.Y.; Guo, L.; Guo, X.H.; Hackenburg, R.W.; Han, R.; Hans, S.; He, M.; Heeger, K.M.; Heng, Y.K.; Hor, Y.K.; Hsiung, Y.B.; Hu, B.Z.; Hu, L.M.; Hu, L.J.; Hu, T.; Hu, W.; Huang, E.C.; Huang, H.X.; Huang, X.T.; Huber, P.; Hussain, G.; Jaffe, D.E.; Jaffke, P.; Jen, K.L.; Jetter, S.; Ji, X.P.; Ji, X.L.; Jiao, J.B.; Johnson, R.A.; Kang, L.; Kettell, S.H.; Kramer, M.; Kwan, K.K.; Kwok, M.W.; Kwok, T.; Langford, T.J.; Lau, K.; Lebanowski, L.; Lee, J.; Lei, R.T.; Leitner, R.; Leung, A.; Leung, J.K.C.; Lewis, C.A.; Li, D.J.; Li, F.; Li, G.S.; Li, Q.J.; Li, S.C.; Li, W.D.; Li, X.N.; Li, X.Q.; Li, Y.F.; Li, Z.B.; Liang, H.; Lin, C.J.; Lin, G.L.; Lin, P.Y.; Lin, S.K.; Ling, J.J.; Link, J.M.; Littenberg, L.; Littlejohn, B.R.; Liu, D.W.; Liu, H.; Liu, J.L.; Liu, J.C.; Liu, S.S.; Lu, C.; Lu, H.Q.; Lu, J.S.; Luk, K.B.; Ma, Q.M.; Ma, X.Y.; Ma, X.B.; Ma, Y.Q.; McDonald, K.T.; McKeown, R.D.; Meng, Y.; Mitchell, I.; Kebwaro, J.Monari; Nakajima, Y.; Napolitano, J.; Naumov, D.; Naumova, E.; Ngai, H.Y.; Ning, Z.; Ochoa-Ricoux, J.P.; Olshevski, A.; Patton, S.; Pec, V.; Peng, J.C.; Piilonen, L.E.; Pinsky, L.; Pun, C.S.J.; Qi, F.Z.; Qi, M.; Qian, X.; Raper, N.; Ren, B.; Ren, J.; Rosero, R.; Roskovec, B.; Ruan, X.C.; Shao, B.B.; Steiner, H.; Sun, G.X.; Sun, J.L.; Tang, W.; Themann, H.; Tsang, K.V.; Tull, C.E.; Tung, Y.C.; Viaux, N.; Viren, B.; Vorobel, V.; Wang, C.H.; Wang, M.; Wang, N.Y.; Wang, R.G.; Wang, W.; Wang, W.W.; Wang, X.; Wang, Y.F.; Wang, Z.; Wang, Z.; Wang, Z.M.; Wei, H.Y.; Wen, L.J.; Whisnant, K.; White, C.G.; Whitehead, L.; Wise, T.; Wong, H.L.H.; Wong, S.C.F.; Worcester, E.; Wu, Q.; Xia, D.M.; Xia, J.K.; Xia, X.; Xing, Z.Z.; Xu, J.Y.; Xu, J.L.; Xu, J.; Xu, Y.; Xue, T.; Yan, J.; Yang, C.G.; Yang, L.; Yang, M.S.; Yang, M.T.; Ye, M.; Yeh, M.; Yeh, Y.S.; Young, B.L.; Yu, G.Y.; Yu, Z.Y.; Zang, S.L.; Zhan, L.; Zhang, C.; Zhang, H.H.; Zhang, J.W.; Zhang, Q.M.; Zhang, Y.M.; Zhang, Y.X.; Zhang, Y.M.; Zhang, Z.J.; Zhang, Z.Y.; Zhang, Z.P.; Zhao, J.; Zhao, Q.W.; Zhao, Y.F.; Zhao, Y.B.; Zheng, L.; Zhong, W.L.; Zhou, L.; Zhou, N.; Zhuang, H.L.; Zou, J.H.

    2015-01-01

    We report a new measurement of electron antineutrino disappearance using the fully-constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9$\\times$10$^5$ GW$_{\\rm th}$-ton-days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six $^{241}$Am-$^{13}$C radioactive calibration sources reduced the background by a factor of two for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of $\\sin^{2}2\\theta_{13}$ and $|\\Delta m^2_{ee}|$ were halved as a result of these improvements. Ana...

  7. Simulation results of liquid and plastic scintillator detectors for reactor antineutrino detection - A comparison

    International Nuclear Information System (INIS)

    A simulation study of two kinds of scintillation detectors has been done using GEANT4. We compare plastic scintillator and liquid scintillator based designs for detecting electron antineutrinos emitted from the core of reactors. The motivation for this study is to set up an experiment at the research reactor facility at BARC for very short baseline neutrino oscillation study and remote reactor monitoring

  8. Search for Time-Independent Lorentz Violation using Muon Neutrino to Muon Antineutrino Transitions in MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P.; et al.

    2016-05-10

    Data from the MINOS experiment has been used to search for mixing between muon neutrinos and muon antineutrinos using a time-independent Lorentz-violating formalism derived from the Standard-Model Extension (SME). MINOS is uniquely capable of searching for muon neutrino-antineutrino mixing given its long baseline and ability to distinguish between neutrinos and antineutrinos on an event-by-event basis. Neutrino and antineutrino interactions were observed in the MINOS Near and Far Detectors from an exposure of 10.56$\\times10^{20}$ protons-on-target from the NuMI neutrino-optimized beam. No evidence was found for such transitions and new, highly stringent limits were placed on the SME coefficients governing them. We place the first limits on the SME parameters $(c_{L})^{TT}_{\\mu\\mu} $ and $(c_{L})^{TT}_{\\tau\\tau}$ at $-8.4\\times10^{-23} < (c_{L})^{TT}_{\\mu\\mu} < 8.0\\times10^{-23}$ and $-8.0\\times10^{-23} < (c_{L})^{TT}_{\\tau\\tau} < 8.4\\times10^{-23}$, and the world's best limits on the $\\tilde{g}^{ZT}_{\\mu\\overline{\\mu}}$ and $\\tilde{g}^{ZT}_{\\tau\\overline{\\tau}}$ parameters at $|\\tilde{g}^{ZT}_{\\mu\\overline{\\mu}}| < 3.3\\times 10^{-23}$ and $|\\tilde{g}^{ZT}_{\\tau\\overline{\\tau}}| < 3.3\\times 10^{-23}$, all limits quoted at $3\\sigma$.

  9. Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra and Decay Heat Calculations

    Directory of Open Access Journals (Sweden)

    Porta A.

    2016-01-01

    Full Text Available Beta decay of fission products is at the origin of decay heat and antineutrino emission in nuclear reactors. Decay heat represents about 7% of the reactor power during operation and strongly impacts reactor safety. Reactor antineutrino detection is used in several fundamental neutrino physics experiments and it can also be used for reactor monitoring and non-proliferation purposes. 92,93Rb are two fission products of importance in reactor antineutrino spectra and decay heat, but their β-decay properties are not well known. New measurements of 92,93Rb β-decay properties have been performed at the IGISOL facility (Jyväskylä, Finland using Total Absorption Spectroscopy (TAS. TAS is complementary to techniques based on Germanium detectors. It implies the use of a calorimeter to measure the total gamma intensity de-exciting each level in the daughter nucleus providing a direct measurement of the beta feeding. In these proceedings we present preliminary results for 93Rb, our measured beta feedings for 92Rb and we show the impact of these results on reactor antineutrino spectra and decay heat calculations.

  10. Photon emission in (anti)neutrino neutral current interactions with nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Wang En; Alvarez-Ruso, Luis; Nieves, Juan [Instituto de Fisica Corpuscular, Centro Mixto CSIC-UV, Valencia (Spain)

    2013-06-10

    Photon emission induced by E{sub {nu}}{approx} 1 GeV (anti)neutrino neutral current (NC) interactions with nuclei is studied with a dynamical microscopic model. This process is a relevant background for {nu}{sub e} appearance oscillation experiments. We find a strong reduction of the cross section due to nuclear effects.

  11. First Measurement of the Muon Anti-Neutrino Charged Current Quasielastic Double-Differential Cross-Section

    Energy Technology Data Exchange (ETDEWEB)

    Grange, Joseph M. [Univ. of Florida, Gainesville, FL (United States)

    2013-01-01

    This dissertation presents the first measurement of the muon antineutrino charged current quasi-elastic double-differential cross section. These data significantly extend the knowledge of neutrino and antineutrino interactions in the GeV range, a region that has recently come under scrutiny due to a number of conflicting experimental results. To maximize the precision of this measurement, three novel techniques were employed to measure the neutrino background component of the data set. Representing the first measurements of the neutrino contribution to an accelerator-based antineutrino beam in the absence of a magnetic field, the successful execution of these techniques carry implications for current and future neutrino experiments.

  12. Charge exchange and energy loss of slowed down heavy ions channeled in silicon crystals; Echanges de charge et perte d'energie d'ions lourds ralentis, canalises dans des cristaux de silicium

    Energy Technology Data Exchange (ETDEWEB)

    Testa, E

    2005-10-15

    This work is devoted to the study of charge exchange processes and of the energy loss of highly charged heavy ions channeled in thin silicon crystals. The two first chapters present the techniques of heavy ion channeling in a crystal, the ion-electron processes and the principle of our simulations (charge exchange and trajectory of channeled ions). The next chapters describe the two experiments performed at the GSI facility in Darmstadt, the main results of which follow: the probability per target atom of the mechanical capture (MEC) of 20 MeV/u U{sup 91+} ions as a function of the impact parameter (with the help of our simulations), the observation of the strong polarization of the target electron gas by the study of the radiative capture and the slowing down of Pb{sup 81+} ions from 13 to 8,5 MeV/u in channeling conditions for which electron capture is strongly reduced. (author)

  13. Measurement and calculation of absolute single- and double-charge-exchange cross sections for O6 + ions at 1.17 and 2.33 keV/u impacting He and H2

    Science.gov (United States)

    Machacek, J. R.; Mahapatra, D. P.; Schultz, D. R.; Ralchenko, Yu.; Chutjian, A.; Simcic, J.; Mawhorter, R. J.

    2014-11-01

    Absolute single- and double-charge-exchange cross sections for the astrophysically prominent O6 + ion with the atomic and molecular targets He and H2 are reported. These collisions give rise to x-ray emissions in the interplanetary medium, planetary atmospheres, and comets as they approach the sun. Measurements have been carried out using the Caltech Jet Propulsion Laboratory electron cyclotron resonance ion source with O6 + at energies of 1.17 and 2.33 keV/u characteristic of the slow and fast components of the solar wind. Absolute charge-exchange (CE) data are derived from knowledge of the target gas pressure, target path length, incident ion current, and charge-exchanged ion currents. These data are compared with results obtained using the n -electron classical trajectory Monte Carlo method. The radiative and Auger evolution of ion populations following one- and two-electron transfers is calculated with the time-dependent collisional-radiative code nomad using atomic data from the flexible atomic code. Calculated CE emission spectra for 100 Å <λ <1400 Å are reported as well and compared with experimental sublevel spectra and cross sections.

  14. Monte Carlo simulation of inclusive pionic reaction around resonance and higher energy perspectives

    International Nuclear Information System (INIS)

    We describe all the inclusive pionic reactions in a variety of nuclei around the resonance region by means of a microscopic many-body calculation that evaluates reaction probabilities, followed by a Monte Carlo simulation which follows the evolution of the pions. We also make an intrusion into the higher energy domain by paying attention to the absorption mechanisms and their repercussions in exclusive single-charge exchange reactions. 27 refs., 11 figs

  15. Energy dependence of total cross sections for neutrino and antineutrino interactions are energies below 35 GeV

    International Nuclear Information System (INIS)

    Further analysis of experimental data obtained in neutrino IHEP-ITEP experiment in Serpukhov is presented. Energy dependences of total cross sections for neutrino-nucleon and antineutrino-nucleon charged-current interactions in the energy range 5-35 GeV have been obtained. There is a tendency for a slow decrease of neutrino cross section with energy increase and a slope constancy of antineutrino cross section. It agrees well with QCD predictions

  16. Neutrino and antineutrino CCQE scattering in the SuperScaling Approximation from MiniBooNE to NOMAD energies

    Energy Technology Data Exchange (ETDEWEB)

    Megias, G.D. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla, 41080 Sevilla (Spain); Amaro, J.E. [Departamento de Física Atómica, Molecular y Nuclear and Instituto Carlos I de Física Teorica y Computacional, Universidad de Granada, 18071 Granada (Spain); Barbaro, M.B., E-mail: barbaro@to.infn.it [Dipartimento di Fisica, Università di Torino and INFN, Sezione di Torino, Via P. Giuria 1, 10125 Torino (Italy); Caballero, J.A. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla, 41080 Sevilla (Spain); Donnelly, T.W. [Center for Theoretical Physics, Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2013-08-09

    We compare the predictions of the SuperScaling model for charged-current quasielastic muonic neutrino and antineutrino scattering from {sup 12}C with experimental data spanning an energy range up to 100 GeV. We discuss the sensitivity of the results to different parametrizations of the nucleon vector and axial-vector form factors. Finally, we show the differences between electron and muon (anti)neutrino cross sections relevant for the νSTORM facility.

  17. Neutrino and antineutrino CCQE scattering in the SuperScaling Approximation from MiniBooNE to NOMAD energies

    CERN Document Server

    Amaro, J E; Caballero, J A; Donnelly, T W; Megias, G D

    2013-01-01

    We compare the predictions of the SuperScaling model for charged current quasielastic muonic neutrino and antineutrino scattering from $^{12}$C with experimental data spanning an energy range up to 100 GeV. We discuss the sensitivity of the results to different parametrizations of the nucleon vector and axial-vector form factors. Finally, we show the differences between electron and muon (anti-)neutrino cross sections relevant for the $\

  18. [Measurements of observables of pion-nucleon reactions]. Progress report

    International Nuclear Information System (INIS)

    This document reports the progress of the research of pion reactions. These include (1) a study to measure observables in the pion-nucleon system in the momentum interval 400 to 700 MeV/c, (2) differential cross section measurements at low energy for pion-nucleon charge exchange, and (3) elastic and inelastic scattering of π+- on 3H and 3He. Individual experiments will be indexed separately

  19. Shifts of neutrino oscillation parameters in reactor antineutrino experiments with non-standard interactions

    CERN Document Server

    Li, Yu-Feng

    2014-01-01

    We discuss reactor antineutrino oscillations with non-standard interactions (NSIs) at the neutrino production and detection processes. The neutrino oscillation probability is calculated with a parametrization of the NSI parameters by splitting them into the averages and differences of the production and detection processes respectively. The average parts induce constant shifts of the neutrino mixing angles from their true values, and the difference parts can generate the energy (and baseline) dependent corrections to the initial mass-squared differences. We stress that only the shifts of mass-squared differences are measurable in reactor antineutrino experiments. Taking Jiangmen Underground Neutrino Observatory (JUNO) as an example, we analyze how NSIs influence the standard neutrino measurements and to what extent we can constrain the NSI parameters.

  20. Search for Perturbations of Nuclear Decay Rates Induced by Reactor Electron Antineutrinos

    CERN Document Server

    Barnes, V E; Bryan, C D; Cinko, N; Deichert, G G; Gruenwald, J T; Heim, J M; Kaplan, H B; LaZur, R; Neff, D; Nistor, J M; Sahelijo, N; Fischbach, E

    2016-01-01

    We report the results of an experiment conducted near the High Flux Isotope Reactor of Oak Ridge National Laboratory, designed to address the question of whether a flux of reactor-generated electron antineutrinos can alter the rates of weak nuclear interaction-induced decays for Mn-54, Na-22, and Co-60. This experiment, while quite sensitive, cannot exclude perturbations less than one or two parts in $10^4$ in $\\beta$ decay (or electron capture) processes, in the presence of an antineutrino flux of $3\\times 10^{12}$ cm$^{-2}$ s$^{-1}$. The present experimental methods are applicable to a wide range of isotopes. Improved sensitivity in future experiments may be possible if we can understand and reduce the dominant systematic uncertainties.

  1. Measurement of antineutrino oscillation with the full detector configuration at Daya Bay

    CERN Document Server

    Grassi, Marco

    2016-01-01

    In this poster, we present the latest measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. A total exposure of $6.9 \\times 10^5$ GW$_{\\mathrm{th}}$ ton days was achieved in November 2013 after 617 day of data taking. The most precise estimates to date of the neutrino mass and mixing parameters $|\\Delta \\mathrm{m}^2_{ee}|$ and $\\sin^2 2 \\theta_{13}$ were obtained with an analysis of the relative antineutrino rates and energy spectra between detectors. The value of the two parameters was found to be $\\sin^2 2 \\theta_{13} = 0.084 \\pm 0.005$ and $|\\Delta \\mathrm{m}^2_{ee}| = (2.42 \\pm 0.11) \\times 10^{-3}\\,\\mathrm{eV}^2$. This report focuses in particular on describing how improvements in the calibration and in the energy response model contributed to achieve this result.

  2. Determination of the fission coefficients in thermal nuclear reactors for antineutrino detection

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Lenilson M. [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Cabral, Ronaldo G., E-mail: rgcabral@ime.eb.b [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Anjos, Joao C.C. dos, E-mail: janjos@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Dept. GLN - G

    2011-07-01

    The nuclear reactors in operation periodically need to change their fuel. It is during this process that these reactors are more vulnerable to occurring of several situations of fuel diversion, thus the monitoring of the nuclear installations is indispensable to avoid events of this nature. Considering this fact, the most promissory technique to be used for the nuclear safeguard for the nonproliferation of nuclear weapons, it is based on the detection and spectroscopy of antineutrino from fissions that occur in the nuclear reactors. The detection and spectroscopy of antineutrino, they both depend on the single contribution for the total number of fission of each actinide in the core reactor, these contributions receive the name of fission coefficients. The goal of this research is to show the computational and mathematical modeling used to determinate these coefficients for PWR reactors. (author)

  3. Indication for the disappearance of reactor electron antineutrinos in the Double Chooz experiment

    CERN Document Server

    Abe, Y; Akiri, T; Anjos, J C dos; Ardellier, F; Barbosa, A F; Baxter, A; Bernstein, A; Bezerra, T J C; Bezrukhov, L; Blucher, E; Bongrand, M; Bowden, N S; Buck, C; Busenitz, J; Cabrera, A; Caden, E; Camilleri, L; Carr, R; Cerrada, M; Chang, P -J; Chimenti, P; Classen, T; Collin, A; Conover, E; Conrad, J M; Cormon, S; Crespo-Anadón, J I; Cribier, M; Crum, K; Cucoanes, A; D'Agostino, M V; Damon, E; Dawson, J V; Dazeley, S; Dierckxsens, M; Dietrich, D; Djurcic, Z; Dracos, M; Durand, V; Efremenko, Y; Endo, Y; Etenko, A; Falk, E; Fallot, M; Fechner, M; von Feilitzsch, F; Felde, J; Fernandes, S M; Franco, D; Franke, A; Franke, M; Furuta, H; Gama, R; Gil-Botella, I; Giot, L; Göger-Neff, M; Gonzalez, L F G; Goodman, M C; Goon, J TM; Greiner, D; Guillon, B; Haag, N; Hagner, C; Hara, T; Hartmann, F X; Hartnell, J; Haruna, T; Haser, J; Hatzikoutelis, A; Hayakawa, T; Hofmann, M; Horton-Smith, G; Ishitsuka, M; Jochum, J; Jollet, C; Jones, C L; Kaether, F; Kalousis, L; Kamyshkov, Y; Kaplan, D; Kawasaki, T; Keefer, G; Kemp, E; de Kerret, H; Kibe, Y; Konno, T; Kryn, D; Kuze, M; Lachenmaier, T; Lane, C E; Langbrandtner, C; Lasserre, T; Letourneau, A; Lhuillier, D; Lima, H P; Lindner, M; Liu, Y; López-Castanõ, J M; LoSecco, J M; Lubsandorzhiev, B K; Lucht, S; McKee, D; Maeda, J; Maesano, C N; Mariani, C; Maricic, J; Martino, J; Matsubara, T; Mention, G; Meregaglia, A; Miletic, T; Milincic, R; Milzstajn, A; Miyata, H; Motta, D; Mueller, Th A; Nagasaka, Y; Nakajima, K; Novella, P; Obolensky, M; Oberauer, L; Onillon, A; Osborn, A; Ostrovskiy, I; Palomares, C; Peeters, S J M; Pepe, I M; Perrin, P; Pfahler, P; Porta, A; Potzel, W; Queval, R; Reichenbacher, J; Reinhold, B; Remoto, A; Reyna, D; Röhling, M; Roth, S; Rubin, H A; Sakamoto, Y; Santorelli, R; Sato, F; Schönert, S; Schoppmann, S; Schwan, U; Schwetz, T; Shaevitz, M; Shrestha, D; Sida, J-L; Sinev, V; Skorokhvatov, M; Smith, E; Stahl, A; Stancu, I; Strait, M; Stüken, A; Suekane, F; Sukhotin, S; Sumiyoshi, T; Sun, Y; Sun, Z; Svoboda, R; Tabata, H; Tamura, N; Terao, K; Tonazzo, A; Toups, M; Thi, H H Trinh; Veyssiere, C; Vignaud, D; Wagner, S; Watanabe, H; White, B; Wiebusch, C; Winslow, L; Worcester, M; Wurm, M; Yanovitch, E; Yermia, F; Zbiri, K; Zimmer, V

    2011-01-01

    The Double Chooz Experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. A ratio of 0.944 $\\pm$ 0.016 (stat) $\\pm$ 0.040 (syst) observed to predicted events was obtained in 101 days of running at the Chooz Nuclear Power Plant in France, with two 4.25 GW$_{th}$ reactors. The results were obtained from a single 10 m$^3$ fiducial volume detector located 1050 m from the two reactor cores. The reactor antineutrino flux prediction used the Bugey4 measurement as an anchor point. The deficit can be interpreted as an indication of a non-zero value of the still unmeasured neutrino mixing parameter \\sang. Analyzing both the rate of the prompt positrons and their energy spectrum we find \\sang = 0.086 $\\pm$ 0.041 (stat) $\\pm$ 0.030 (syst), or, at 90% CL, 0.015 $<$ \\sang $\\ <$ 0.16.

  4. The Physics and Nuclear Nonproliferation Goals of WATCHMAN: A WAter CHerenkov Monitor for ANtineutrinos

    CERN Document Server

    Askins, M; Bernstein, A; Dazeley, S; Dye, S T; Handler, T; Hatzikoutelis, A; Hellfeld, D; Jaffke, P; Kamyshkov, Y; Land, B J; Learned, J G; Marleau, P; Mauger, C; Gann, G D Orebi; Roecker, C; Rountree, S D; Shokair, T M; Smy, M B; Svoboda, R; Sweany, M; Vagins, M R; van Bibber, K A; Vogelaar, R B; Wetstein, M J; Yeh, M

    2015-01-01

    This article describes the physics and nonproliferation goals of WATCHMAN, the WAter Cherenkov Monitor for ANtineutrinos. The baseline WATCHMAN design is a kiloton scale gadolinium-doped (Gd) light water Cherenkov detector, placed 13 kilometers from a civil nuclear reactor in the United States. In its first deployment phase, WATCHMAN will be used to remotely detect a change in the operational status of the reactor, providing a first- ever demonstration of the potential of large Gd-doped water detectors for remote reactor monitoring for future international nuclear nonproliferation applications. During its first phase, the detector will provide a critical large-scale test of the ability to tag neutrons and thus distinguish low energy electron neutrinos and antineutrinos. This would make WATCHMAN the only detector capable of providing both direction and flavor identification of supernova neutrinos. It would also be the third largest supernova detector, and the largest underground in the western hemisphere. In a...

  5. Quasielastic neutrino and antineutrino interaction at the Serpukhov accelerator (IHEP-ITEP collaboration)

    International Nuclear Information System (INIS)

    Preliminary results on the energy dependence of quasielastic differential and total cross-sections for neutrino and antineutrino scattering in the νsub(μ)n → μ-p and anti νsub(μ)p → μ+n interactions in the energy region 3 <= E <= 30 GeV obtined in the aluminium spark chamber detector are presented. The data are compared with the predictions of classical V-A theory with current vector conservation assumption. The best fit parameters for axial mass are Msub(A)=1.00+-0.07 and Msub(A)=1.04+-0.08 from the neutrino and antineutrino data respectively. It is shown that experimental data are in good agreement with the predictions of the standart V-A theory

  6. Advances toward a transportable antineutrino detector system for reactor monitoring and safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Reyna, D. [Sandia National Laboratories, Livermore, CA 94550 (United States); Bernstein, A. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Lund, J.; Kiff, S.; Cabrera-Palmer, B. [Sandia National Laboratories, Livermore, CA 94550 (United States); Bowden, N. S.; Dazeley, S.; Keefer, G. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2011-07-01

    Nuclear reactors have served as the neutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these very weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Our SNL/LLNL collaboration has demonstrated that such antineutrino based monitoring is feasible using a relatively small cubic meter scale liquid scintillator detector at tens of meters standoff from a commercial Pressurized Water Reactor (PWR). With little or no burden on the plant operator we have been able to remotely and automatically monitor the reactor operational status (on/off), power level, and fuel burnup. The initial detector was deployed in an underground gallery that lies directly under the containment dome of an operating PWR. The gallery is 25 meters from the reactor core center, is rarely accessed by plant personnel, and provides a muon-screening effect of some 20-30 meters of water equivalent earth and concrete overburden. Unfortunately, many reactor facilities do not contain an equivalent underground location. We have therefore attempted to construct a complete detector system which would be capable of operating in an aboveground location and could be transported to a reactor facility with relative ease. A standard 6-meter shipping container was used as our transportable laboratory - containing active and passive shielding components, the antineutrino detector and all electronics, as well as climate control systems. This aboveground system was deployed and tested at the San Onofre Nuclear Generating Station (SONGS) in southern California in 2010 and early 2011. We will first present an overview of the initial demonstrations of our below ground detector. Then we will describe the aboveground system and the technological developments of the two antineutrino

  7. Improved limit on the electron-antineutrino rest mass from tritium ß-decay

    OpenAIRE

    Weinheimer, Christian; Przyrembel, Michael; Backe, Hartmut; H. Barth; Bonn, Jochen; Degen, Beate; Edling, Thomas; Fischer, H.; Fleischmann, L.; Grooß, Jens-Uwe; Haid, R.; Hermanni, Antje; Kube, Gero; Leiderer, Paul; Loeken, Thomas

    1993-01-01

    The endpoint region of the β-spectrum of tritium was remeasured by an electrostatic spectrometer with magnetic guiding field. It enabled the search for a rest mass of the electron-antineutrino with improved precision. The result is m2v=−39±34stat±15syst(eV/c2)2, from which an upper limit of mv

  8. Upper limit on the cross section for reactor antineutrinos changing 22Na decay rates

    CERN Document Server

    de Meijer, R J

    2014-01-01

    In this paper we present results of a long-term observation of the decay of 22Na in the presence of a nuclear fission reactor. The measurements were made outside the containment wall of and underneath the Koeberg nuclear power plant near Cape Town, South Africa. Antineutrino fluxes ranged from ~5*10^11 to 1.6*10^13 cm^-2 s^-1 during this period. We show that the coincidence summing technique provides a sensitive tool to measure a change in the total decay constant as well as the branching ratio between EC and beta+ decay of 22Na to the first excited state in 22Ne. We observe a relative change in count rate between reactor-ON and reactor-OFF equal to (-0.51+/-0.11)*10^-4. After evaluating possible systematic uncertainties we conclude that the effect is either due to a hidden instrumental cause or due to an interaction between antineutrinos and the 22Na nucleus. An upper limit of ~0.03 barn has been deduced for observing any change in the decay rate of 22Na due to antineutrino interactions.

  9. Detection of anomalous reactor activity using antineutrino count evolution over the course of a reactor cycle

    Science.gov (United States)

    Bulaevskaya, Vera; Bernstein, Adam

    2011-06-01

    This paper analyzes the sensitivity of antineutrino count rate measurements to changes in the fissile content of civil power reactors. Such measurements may be useful in IAEA reactor safeguards applications. We introduce a hypothesis testing procedure to identify statistically significant differences between the antineutrino count rate evolution of a standard "baseline" fuel cycle and that of an anomalous cycle, in which plutonium is removed and replaced with an equivalent fissile worth of uranium. The test would allow an inspector to detect anomalous reactor activity, or to positively confirm that the reactor is operating in a manner consistent with its declared fuel inventory and power level. We show that with a reasonable choice of detector parameters, the test can detect replacement of 82 kg of plutonium in 90 days with 95% probability, while controlling the false positive rate at 5%. We show that some improvement on this level of sensitivity may be obtained by various means, including use of the method in conjunction with existing reactor safeguards methods. We also identify a necessary and sufficient minimum daily antineutrino count rate and a maximum tolerable background rate to achieve the quoted sensitivity, and list examples of detectors in which such rates have been attained.

  10. Lithium antineutrino source in the tandem scheme of the accelerator and neutron producting tungsten target

    CERN Document Server

    Lyashuk, V I

    2016-01-01

    The antineutrinos of the neutron rich 8Li isotope is characterized by hard and good defined spectrum - averaged energy is 6.5 MeV and maximal - up to 13 MeV. An intensive antineutrino source with such parameters can be unique instrument for neutrino investigations and especially for search of sterile neutrinos. The 8Li can be produced by (n,gamma)-activation of 7Li isotope. The proposed scheme of the antineutrino source is based on the lithium blanket around the accelerator neutron producting target. We propose to use heavy water solution of the lithium hydroxide instead of lithium in metallic state. Such solution for lithium blanket substance ensure the large perspectives in real steps for creation of this installation. An analyses of neutron fields in the blanket and distribution of 8Li creation allows to propose the next principal steps in the construction of the lithium blanket. We propose to enclose the blanket volume isolating it's central part with more high 8Li production. This solution allows to decr...

  11. How Unequal Fluxes of High Energy Astrophysical Neutrinos and Antineutrinos can Fake New Physics

    CERN Document Server

    Nunokawa, Hiroshi; Funchal, Renata Zukanovich

    2016-01-01

    Flavor ratios of very high energy astrophysical neutrinos, which can be studied at the Earth by a neutrino telescope such as IceCube, can serve to diagnose their production mechanism at the astrophysical source. The flavor ratios for neutrinos and antineutrinos can be quite different as we do not know how they are produced in the astrophysical environment. Due to this uncertainty the neutrino and antineutrino flavor ratios at the Earth also could be quite different. Nonetheless, it is generally assumed that flavor ratios for neutrinos and antineutrinos are the same at the Earth, in fitting the high energy astrophysical neutrino data. This is a reasonable assumption for the limited statistics for the data we currently have. However, in the future the fit must be performed allowing for a possible discrepancy in these two fractions in order to be able to disentangle different production mechanisms at the source from new physics in the neutrino sector. To reinforce this issue, in this work we show that a wrong as...

  12. Neutrino–antineutrino mass splitting in the Standard Model and baryogenesis

    Directory of Open Access Journals (Sweden)

    Kazuo Fujikawa

    2015-04-01

    Full Text Available On the basis of a previously proposed mechanism of neutrino–antineutrino mass splitting in the Standard Model, which is Lorentz and SU(2×U(1 invariant but non-local to evade the CPT theorem, we discuss the possible implications of neutrino–antineutrino mass splitting on neutrino physics and baryogenesis. It is shown that non-locality within a distance scale of the Planck length, that may not be fatal to unitarity in a generic effective theory, can generate the neutrino–antineutrino mass splitting of the order of the observed neutrino mass differences, which is tested in oscillation experiments, and a non-negligible baryon asymmetry depending on the estimate of sphaleron dynamics. The one-loop order induced electron–positron mass splitting in the Standard Model is shown to be finite and estimated at ∼10−20 eV, well below the experimental bound <10−2 eV. The induced CPT violation in the K-meson in the Standard Model is expected to be even smaller and well below the experimental bound |mK−mK¯|<0.44×10−18 GeV.

  13. Supernova Relic Electron Neutrinos and anti-Neutrinos in future Large-scale Observatories

    CERN Document Server

    Volpe, C

    2007-01-01

    We investigate the signal from supernova relic neutrinos in future large scale observatories, such as MEMPHYS (UNO, Hyper-K), LENA and GLACIER, at present under study. We discuss that complementary information might be gained from the observation of supernova relic electron anti-neutrinos and neutrinos using the scattering on protons on one hand, and on nuclei such as oxygen, carbon or argon on the other hand. When determining the relic neutrino fluxes we also include, for the first time, the coupling of the neutrino magnetic moment to magnetic fields within the core-collapse supernova. We present numerical results on both the relic electron neutrino and anti-neutrino fluxes and on the number of events for electron neutrinos on carbon, oxygen and argon, as well as electron anti-neutrinos on protons, for various oscillation scenarios. The observation of supernova relic neutrinos might provide us with unique information on core-collapse supernova explosions, on the star formation history and on neutrino propert...

  14. Experimental study of invariance violations in neutrino and antineutrino reactions at high energy

    International Nuclear Information System (INIS)

    This work is dedicated to the study of the structure functions in neutrino-nucleon interactions and to the interpretation of observed violations of scaling invariance. The first chapter describes the experimental setting, the Cargamelle cloud chamber has been used. The second chapter presents the data analysis, the event selection methodology, the muon identification and the energy correction that takes into account the non-detected particles. We also present the bi-dimensional x and q2 distribution of events that is necessary to the determination of the structure functions. In the third chapter we detail the theoretical basis of our analysis: we define relevant kinematic variables and we discuss the scale invariance in the light of the quark-parton model. The violations of the scale invariance are considered first in the formalism of quantum chromodynamics and then in the view of higher twist or mass corrections. The fourth chapter deals with the experimental determination of the structure functions and of the violations of the scaling invariance. (A.C.)

  15. Nuclear Reactor Simulations for Unveiling Diversion Scenarios: capabilities of the antineutrino probe

    Energy Technology Data Exchange (ETDEWEB)

    Bui, V.M.; Fallot, M.; Giot, L.; Guillon, B.; Martino, J.; Yermia, F. [SUBATECH - CNRS-IN2P3 - Univ. of Nantes - EMN, Nantes (France); Nuttin, A. [LPSC - CNRS-IN2P3/UJF/INPG, Grenoble (France)

    2009-06-15

    After many years of fundamental research, physicists have a good understanding of the neutrinos detection techniques. It is now possible to apply neutrino physics as a new tool to monitor nuclear power plants. We already know that modest size detectors are achievable to fulfill that task such as the SONGS 1 and the future Nucifer detectors. In parallel, sophisticated simulations of reactors and their associated antineutrino flux and energy spectrum have been developed to predict the neutrino signature of the fuel burnup and of a diversion. Taking advantage of the tremendous quantity of information available nowadays in nuclear databases, the total {beta} spectrum of a reactor is built by adding the contributions of all the {beta} branches involved in the decay of all fission products (FP). A package called MCNP Utility for Reactor Evolution (MURE) computes the fuel and FP inventories by simulating the neutronics and time evolution of a reactor core. MURE, initially developed by CNRS/IN2P3/LPSC Grenoble and IPN Orsay to study Generation IV reactors, is a precision code written in C++ which automates the preparation and computation of successive MCNP calculations either for precision burnup or thermal-hydraulics purpose. MURE will be soon available at NEA. The only user-defined inputs driving the time evolution of the isotopic composition of the core are the initial fuel composition, the refueling scheme, and the thermal power. The evolution of the antineutrino flux and energy spectrum with the fuel burnup, as well as the effect of neutron capture on various nuclei are taken into account. Nonproliferation scenarios and burnup monitoring with antineutrinos have been studied using these tools for PWR and Candu reactors. A full core simulation of an N4-PWR will be presented in a first part. Gross unveiling diversion scenarios using a PWR have been simulated in order to test the ability of the antineutrino probe. A channel of a Heavy Water Reactor (Candu 600) loaded with

  16. Neutrino nucleus reactions at high energies within the GiBUU model

    CERN Document Server

    Lalakulich, O; Leitner, T; Mosel, U

    2011-01-01

    The GiBUU model, which implements all reaction channels relevant at medium neutrino energy, is used to investigate the neutrino and antineutrino scattering on iron. Results for integrated cross sections are compared with NOMAD and MINOS data. It is shown, that final state interaction can noticeably change the spectra of the outgoing hadrons. Predictions for the Miner$\

  17. High resolution studies of low lying GT strength using the (d,He-2) reaction and its impact on electron-capture rates in stellar environments

    NARCIS (Netherlands)

    Wortche, HJ; van den Berg, AM; Hannen, VM; Harakeh, MN; de Huu, MA; De Frenne, D; Hagemann, M; Heyse, J; Jacobs, E; Baumer, C; Frekers, D; Schmidt, R

    2003-01-01

    Gamow-Teller transitions in fp-shell nuclei have been studied using the Ni-58(d, He-2) charge exchange reaction at an incident energy of 170 MeV and forward angles. The measurements have been performed at AGOR using the Big-Bite Spectrometer and the EuroSuperNova focal-plane detection system. The un

  18. Quasi-elastic interactions and one-pion production by neutrinos and anti-neutrinos on a deuterium target

    International Nuclear Information System (INIS)

    In this thesis, the weak charged current interactions of neutrinos and antineutrinos with nucleons are described, in which the neutrino scatters in a quasi-elastic way with the nucleon, leaving an excited nucleon state. The experiments have been performed in the bubble chamber BEBC, filled with deuterium and exposed to the CERN Wide Band (anti-)neutrino beams. This gave the opportunity to study both interactions on protons and on neutrons separately, whereas the measurement of the exclusive channels could be performed with a high precision. After a short introduction of the relevant theories (standard model; QCD; one-pion production models; FKR quark model), the experimental set-up at CERN is described as well as the bubble chamber picture facility in Amsterdam. Next, results of the neutrino and antineutrino experiments are given followed by a comparison with theory. (Auth.)

  19. Measurements of the Inclusive Neutrino and Antineutrino Charged Current Cross Sections in MINERvA Using the Low-$\

    CERN Document Server

    DeVan, J; Aliaga, L; Altinok, O; Bellantoni, L; Bercellie, A; Betancourt, M; Bodek, A; Budd, H; Cai, T; Carneiro, M F; da Motta, H; Devan, J; Dytman, S A; Díaz, G A; Eberly, B; Endress, E; Felix, J; Fields, L; Fine, R; Gago, A M; Galindo, R; Gallagher, H; Ghosh, A; Gran, R; Harris, D A; Higuera, A; Hurtado, K; Kleykamp, J; Kordosky, M; Le, T; Maher, E; Manly, S; Mann, W A; Marshall, C M; Caicedo, D A Martinez; McFarland, K S; McGivern, C L; McGowan, A M; Messerly, B; Miller, J; Mislivec, A; Morfín, J G; Mousseau, J; Naples, D; Nelson, J K; Norrick, A; Nuruzzaman,; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Ramirez, M A; Ransome, R D; Ray, H; Rimal, D; Rodrigues, P A; Ruterbories, D; Schellman, H; Salinas, C J Solano; Sultana, M; Falero, S Sánchez; Tice, B G; Valencia, E; Wolcott, J; Wospakrik, M; Zhang, D

    2016-01-01

    The total cross sections are important ingredients for the current and future neutrino oscillation experiments. We present measurements of the total charged-current neutrino and antineutrino cross sections on scintillator (CH) in the NuMI low-energy beamline using an {\\em in situ} prediction of the shape of the flux as a function of neutrino energy from 2--50 GeV. This flux prediction takes advantage of the fact that neutrino and antineutrino interactions with low nuclear recoil energy ($\

  20. Light collection and pulse-shape discrimination in elongated scintillator cells for the PROSPECT reactor antineutrino experiment

    Science.gov (United States)

    Ashenfelter, J.; Balantekin, B.; Band, H. R.; Barclay, G.; Bass, C. D.; Berish, D.; Bowden, N. S.; Bowes, A.; Brodsky, J. P.; Bryan, C. D.; Cherwinka, J. J.; Chu, R.; Classen, T.; Commeford, K.; Davee, D.; Dean, D.; Deichert, G.; Diwan, M. V.; Dolinski, M. J.; Dolph, J.; Dwyer, D. A.; Gaison, J. K.; Galindo-Uribarri, A.; Gilje, K.; Glenn, A.; Goddard, B. W.; Green, M.; Han, K.; Hans, S.; Heeger, K. M.; Heffron, B.; Jaffe, D. E.; Langford, T. J.; Littlejohn, B. R.; Martinez Caicedo, D. A.; McKeown, R. D.; Mendenhall, M. P.; Mueller, P.; Mumm, H. P.; Napolitano, J.; Neilson, R.; Norcini, D.; Pushin, D.; Qian, X.; Romero, E.; Rosero, R.; Saldana, L.; Seilhan, B. S.; Sharma, R.; Sheets, S.; Stemen, N. T.; Surukuchi, P. T.; Varner, R. L.; Viren, B.; Wang, W.; White, B.; White, C.; Wilhelmi, J.; Williams, C.; Wise, T.; Yao, H.; Yeh, M.; Yen, Y. R.; Zangakis, G.; Zhang, C.; Zhang, X.

    2015-11-01

    A meter-long, 23-liter EJ-309 liquid scintillator detector has been constructed to study the light collection and pulse-shape discrimination performance of elongated scintillator cells for the PROSPECT reactor antineutrino experiment. The magnitude and uniformity of light collection and neutron-gamma discrimination power in the energy range of antineutrino inverse beta decay products have been studied using gamma and spontaneous fission calibration sources deployed along the cell axis. We also study neutron-gamma discrimination and light collection abilities for differing PMT and reflector configurations. Key design features for optimizing MeV-scale response and background rejection capabilities are identified.

  1. Light Collection and Pulse-Shape Discrimination in Elongated Scintillator Cells for the PROSPECT Reactor Antineutrino Experiment

    CERN Document Server

    Ashenfelter, J; Band, H R; Barclay, G; Bass, C D; Berish, D; Bowden, N S; Bowes, A; Brodsky, J P; Bryan, C D; Cherwinka, J J; Chu, R; Classen, T; Commeford, K; Davee, D; Dean, D; Deichert, G; Diwan, M V; Dolinski, M J; Dolph, J; Dwyer, D A; Gaison, J K; Galindo-Uribarri, A; Gilje, K; Glenn, A; Goddard, B W; Green, M; Han, K; Hans, S; Heeger, K M; Heffron, B; Jaffe, D E; Langford, T J; Littlejohn, B R; Caicedo, D A Martinez; McKeown, R D; Mendenhall, M P; Mueller, P; Mumm, H P; Napolitano, J; Neilson, R; Norcini, D; Pushin, D; Qian, X; Romero, E; Rosero, R; Saldana, L; Seilhan, B S; Sharma, R; Sheets, S; Stemen, N T; Surukuchi, P T; Varner, R L; Viren, B; Wang, W; White, B; White, C; Wilhelmi, J; Williams, C; Wise, T; Yao, H; Yeh, M; Yen, Y -R; Zangakis, G; Zhang, C; Zhang, X

    2015-01-01

    A meter-long, 23-liter EJ-309 liquid scintillator detector has been constructed to study the light collection and pulse-shape discrimination performance of elongated scintillator cells for the PROSPECT reactor antineutrino experiment. The magnitude and uniformity of light collection and neutron/gamma discrimination power in the energy range of antineutrino inverse beta decay products have been studied using gamma and spontaneous fission calibration sources deployed along the cell long axis. We also study neutron-gamma discrimination and light collection abilities for differing PMT and reflector configurations. Key design features for optimizing MeV-scale response and background rejection capabilities are identified.

  2. Neutrino-antineutrino pair production by a photon in a dense matter

    CERN Document Server

    Lobanov, A E

    2006-01-01

    The possibility of radiative effects that are due to interaction of fermions with a dense matter is investigated. Neutrino-antineutrino photo-production is studied. The rate of this process is calculated in the Furry picture. It is demonstrated that this effect does not disappear even if the medium refractive index is assumed to be equal to unity. The rate obtained strongly depends on the polarization states of the particles involved. This leads to evident spatial asymmetries, which may have certain consequences observable in astrophysical and cosmological studies.

  3. Recent Results of the Relativistic Green's Function Model in Quasielastic Neutrino and Antineutrino-Nucleus Scattering

    CERN Document Server

    Giusti, Carlotta

    2014-01-01

    The analysis of quasielastic neutrino and antineutrino-nucleus scattering cross sections requires relativistic theoretical descriptions also accounting for the role of final-state interactions (FSI). In the relativistic Green's function (RGF) model FSI are described by a complex optical potential where the imaginary part recovers the contribution of final-state channels that are not included in other models based on the impulse approximation. The RGF results are compared with the data recently published by the MiniBooNE and MINER$\

  4. Measurement of the electron antineutrino mass from the beta spectrum of gaseous tritium

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, D.A.

    1986-12-01

    A measurement has been made of the mass of the electron antineutrino using the beta spectrum from a source of gaseous molecular tritium, and an upper limit of 36 eV/c/sup 2/ has been set on this mass. This measurement is the first upper limit on neutrino mass that does not rely on assumptions about the atomic configuration after the beta decay, and it has significantly smaller systematic errors associated with it than do previous measurements. 130 refs., 83 figs., 8 tabs.

  5. Charged kaon production by coherent scattering of neutrinos and antineutrinos on nuclei

    CERN Document Server

    Alvarez-Ruso, L; Simo, I Ruiz; Valverde, M; Vacas, M J Vicente

    2012-01-01

    With the aim of achieving a better and more complete understanding of neutrino interactions with nuclear targets, the coherent production of charged kaons induced by neutrinos and antineutrinos is investigated in the energy range of some of the current neutrino experiments. We follow a microscopic approach which, at the nucleon level, incorporates the most important mechanisms allowed by the chiral symmetry breaking pattern of QCD. The distortion of the outgoing (anti)kaon is taken into account by solving the Klein-Gordon equation with realistic optical potentials. Angular and momentum distributions are studied, as well as the energy and nuclear dependence of the total cross section.

  6. Radiative capture and charge exchange of negative pions on protons at 26.4 and 39.3 MeV

    International Nuclear Information System (INIS)

    The π-p->γn and π-p->π0n reactions were studied at laboratory pion kinetic energies of 27.4 and 39.3 MeV for 9 angles. The differential cross sections of the π-p->γn reaction are compared with previous data and with several calculations. The π-p->π0n differential cross sections were obtained by unfolding the energy spectra of the π0 γ-ray decays. Pion-nucleon phase shifts and scattering lengths are deduced and good agreement is obtained with the elastic channels, supporting isospin invariance. (orig.)

  7. Radiative capture and charge exchange of negative pions on protons at 27.4 and 39.3 MeV

    International Nuclear Information System (INIS)

    The π-p → γn and π-p → π0n reactions were studied at laboratory pion kinetic energies of 27.4 and 39.3 MeV for 9 angles. The differential cross-sections of the π-p → γn reaction are compared with previous data and with several calculations. The π-p → π0n differential cross-sections were obtained by unfolding the energy spectra of the π0 γ-ray decays. Pion-nucleon phase shifts and scattering lengths are deduced and good agreement is obtained with the elastic channels, supporting isospin invariance

  8. New antineutrino energy spectra predictions from the summation of beta decay branches of the fission products.

    Science.gov (United States)

    Fallot, M; Cormon, S; Estienne, M; Algora, A; Bui, V M; Cucoanes, A; Elnimr, M; Giot, L; Jordan, D; Martino, J; Onillon, A; Porta, A; Pronost, G; Remoto, A; Taín, J L; Yermia, F; Zakari-Issoufou, A-A

    2012-11-16

    In this Letter, we study the impact of the inclusion of the recently measured beta decay properties of the (102;104;105;106;107)Tc, (105)Mo, and (101)Nb nuclei in an updated calculation of the antineutrino energy spectra of the four fissible isotopes (235,238)U and (239,241)Pu. These actinides are the main contributors to the fission processes in pressurized water reactors. The beta feeding probabilities of the above-mentioned Tc, Mo, and Nb isotopes have been found to play a major role in the γ component of the decay heat of (239)Pu, solving a large part of the γ discrepancy in the 4-3000 s range. They have been measured by using the total absorption technique, insensitive to the pandemonium effect. The calculations are performed by using the information available nowadays in the nuclear databases, summing all the contributions of the beta decay branches of the fission products. Our results provide a new prediction of the antineutrino energy spectra of (235)U, (239,241)Pu, and, in particular, (238)U for which no measurement has been published yet. We conclude that new total absorption technique measurements are mandatory to improve the reliability of the predicted spectra.

  9. Model-independent determination of the axial mass parameter in quasielastic antineutrino-nucleon scattering

    CERN Document Server

    Bhattacharya, Bhubanjyoti; Tropiano, Anthony J

    2015-01-01

    Understanding the charged current quasielestic (CCQE) neutrino-nucleus interaction is important for precision studies of neutrino oscillations. The theoretical description of the interaction depends on the combination of a nuclear model with the knowledge of form factors. While the former has received considerable attention, the latter, in particular the axial form factor, is implemented using the historical dipole model. Instead, we use a model-independent approach, presented in a previous study, to analyze the muon antineutrino CCQE mineral oil data published by the MiniBooNE collaboration. We combine the cross section for scattering of antineutrinos off protons in carbon and hydrogen, using the same axial form factor for both. The extracted value of the axial mass parameter $m_A = 0.84^{+0.12}_{-0.04} \\pm {0.11} \\, {\\rm GeV}$ is in very good agreement with the model-independent value extracted from MiniBooNE's neutrino data. Going beyond a one-parameter description of the axial form factor, we extract valu...

  10. New antineutrino energy spectra predictions from the summation of beta decay branches of the fission products

    CERN Document Server

    Fallot, M; Estienne, M; Algora, A; Bui, V M; Cucoanes, A; Elnimr, M; Giot, L; Jordan, D; Martino, J; Onillon, A; Porta, A; Pronost, G; Taín, J L; Yermia, F; Zakari-Issoufou, A -A

    2012-01-01

    In this paper, we study the impact of the inclusion of the recently measured beta decay properties of the $^{102;104;105;106;107}$Tc, $^{105}$Mo, and $^{101}$Nb nuclei in an updated calculation of the antineutrino energy spectra of the four fissible isotopes $^{235, 238}$U, and $^{239,241}$Pu. These actinides are the main contributors to the fission processes in Pressurized Water Reactors. The beta feeding probabilities of the above-mentioned Tc, Mo and Nb isotopes have been found to play a major role in the $\\gamma$ component of the decay heat of $^{239}$Pu, solving a large part of the $\\gamma$ discrepancy in the 4 to 3000\\,s range. They have been measured using the Total Absorption Technique (TAS), avoiding the Pandemonium effect. The calculations are performed using the information available nowadays in the nuclear databases, summing all the contributions of the beta decay branches of the fission products. Our results provide a new prediction of the antineutrino energy spectra of $^{235}$U, $^{239,241}$Pu ...

  11. Limits on the oscillation plus decay model using published MINOS neutrino and antineutrino data

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Abner Leonel Gadelha; Gomes, Ricardo Avelino [Universidade Federal de Goias (UFGO), Goiania (Brazil). Instituto de Fisica; Peres, Orlando Goulart [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Instituto de Fisica Gleb Wataghin

    2013-07-01

    Full text: The neutrino oscillation model is the theoretical model that explains the so called anomalous neutrino phenomena. Models such as neutrino decay and decoherence failed to explain the neutrino experimental results. Nevertheless, it was proposed that the oscillation model could be the dominant model with the possibility to add alternative models to it and determine limits for the parameters of the additional models. In this phenomenological work we considered the neutrino oscillation plus decay model and used the published data from the MINOS experiment. MINOS is a long-baseline neutrino experiment with two magnetized detectors (the Near Detector at Fermilab, 1 km from the target and depth of 225 meters of water equivalent (mwe), and the Far Detector at Soudan, MN, 735 km from the target and depth of 2100 mwe) exposed to the NuMI (Neutrinos at the Main Injector) beam. We used recent results from neutrino and antineutrino configurations of the NuMI beam and fitted by a 2-flavor oscillation model - transition from ν{sub μ} (ν{sub -}bar{sub μ}) to ν{sub τ} (ν{sub -}bar{sub τ}). We show the best fit and allowed region found for neutrino and antineutrino data, reproducing the published results. We then combined the data and under the oscillation plus decay framework calculated 1D and 2D allowed regions to determine limits for the decay parameter. (author)

  12. Measurement of the Antineutrino Double-Differential Charged-Current Quasi-Elastic Scattering Cross Section at MINERvA

    Energy Technology Data Exchange (ETDEWEB)

    Patrick, Cheryl [Northwestern U.

    2016-01-01

    Next-generation neutrino oscillation experiments, such as DUNE and Hyper-Kamiokande, hope to measure charge-parity (CP) violation in the lepton sector. In order to do this, they must dramatically reduce their current levels of uncertainty, particularly those due to neutrino-nucleus interaction models. As CP violation is a measure of the difference between the oscillation properties of neutrinos and antineutrinos, data about how the less-studied antineutrinos interact is especially valuable. We present the MINERvA experiment's first double-differential scattering cross sections for antineutrinos on scintillator, in the few-GeV range relevant to experiments such as DUNE and NOvA. We also present total antineutrino-scintillator quasi-elastic cross sections as a function of energy, which we compare to measurements from previous experiments. As well as being useful to help reduce oscillation experiments' uncertainty, our data can also be used to study the prevalence of various cor relation and final-state interaction effects within the nucleus. We compare to models produced by different model generators, and are able to draw first conclusions about the predictions of these models.

  13. First Observations of Separated Atmospheric Muon Neutrino and Muon Anti-Neutrino Events in the MINOS Detector

    CERN Document Server

    Adamson, P; Allison, W W M; Alner, G J; Anderson, K; Andreopoulos, C; Andrews, M; Andrews, R; Arroyo, C; Avvakumov, S; Ayres, D S; Baller, B; Barish, B; Barker, M A; Barnes, P D; Barr, G; Barrett, W L; Beall, E; Becker, B R; Belias, A; Bergfeld, T; Bernstein, R H; Bhattacharya, D; Bishai, M; Blake, A; Bocean, V; Bock, B; Bock, G J; Bogert, D; Border, P M; Bower, C; Boyd, S; Buckley-Geer, E; Byon-Wagner, A; Böhm, J; Böhnlein, D J; Cabrera, A; Chapman, J D; Chase, T R; Chernichenko, S K; Childress, S; Choudhary, B C; Cobb, J H; Cossairt, J D; Courant, H; Crane, D A; Culling, A J; Dawson, J W; De Muth, D M; De Santo, A; Dierckxsens, M; Diwan, M V; Dorman, M; Drake, G; Ducar, R; Durkin, T; Erwin, A R; Escobar, C O; Evans, J; Fackler, O D; Falk-Harris, E; Feldman, G J; Felt, N; Fields, T H; Ford, R; Frohne, M V; Gallagher, H R; Gebhard, M; Godley, A; Gogos, J; Goodman, M C; Gornushkin, Yu; Gouffon, P; Grashorn, E; Grossman, N; Grudzinski, J J; Grzelak, K; Guarino, V; Habig, A; Halsall, R; Hanson, J; Harris, D; Harris, P G; Hartnell, J; Hartouni, E P; Hatcher, R; Heller, K; Hill, N; Ho, Y; Howcroft, C; Hylen, J; Ignatenko, M A; Indurthy, D; Irwin, G M; James, C; Jenner, L; Jensen, D; Joffe-Minor, T M; Kafka, T; Kang, H J; Kasahara, S M; Kilmer, J; Kim, H; Koizumi, G; Kopp, S; Kordosky, M; Koskinen, D J; Kostin, M; Krakauer, D A; Kumaratunga, S; Ladran, A S; Lang, K; Laughton, C; Lebedev, A; Lee, R; Lee, W Y; Libkind, M A; Litchfield, P J; Litchfield, R P; Liu, J; Longley, N P; Lucas, P; Luebke, W; Madani, S; Maher, E; Makeev, V; Mann, W A; Marchionni, A; Marino, A D; Marshak, M L; Marshall, J S; McDonald, J; McGowan, A; Meier, J R; Merzon, G I; Messier, M D; Michael, D G; Milburn, R H; Miller, J L; Miller, W H; Mishra, S R; Miyagawa, P S; Moore, Cristopher; Morf, J; Morse, R; Mualem, L; Mufson, S; Murgia, S; Murtagh, M J; Musser, J; Naples, D; Nelson, C; Nelson, J K; Newman, H B; Nezrick, F A; Nichol, R J; Nicholls, T C; Ochoa-Ricoux, J P; Oliver, J; Oliver, W P; Onuchin, V A; Osiecki, T; Ospanov, R; Paley, J; Paolone, V; Para, A; Patzak, T; Pavlovich, Z; Pearce, G F; Pearson, N; Peck, C W; Perry, C; Peterson, E A; Petyt, D A; Ping, H; Piteira, R; Pla-Dalmau, A; Plunkett, R K; Price, L E; Proga, M; Pushka, D R; Rahman, D; Rameika, R A; Raufer, T M; Read, A L; Rebel, B; Reyna, D E; Rosenfeld, C; Rubin, H A; Ruddick, K; Ryabov, V A; Saakyan, R; Sanchez, M C; Saoulidou, N; Schneps, J; Schoessow, P V; Schreiner, P; Schwienhorst, R; Semenov, V K; Seun, S M; Shanahan, P; Shield, P D; Smart, W; Smirnitsky, A V; Smith, C; Smith, P N; Sousa, A; Speakman, B; Stamoulis, P; Stefanik, A; Sullivan, P; Swan, J M; Symes, P A; Tagg, N; Talaga, R L; Tetteh-Lartey, E; Thomas, J; Thompson, J; Thomson, M A; Thron, J L; Trendler, R; Trevor, J; Trostin, I; Tsarev, V A; Tzanakos, G S; Urheim, J; Vahle, P; Vakili, M; Vaziri, K; Velissaris, C; Verebryusov, V; Viren, B; Wai, L; Ward, C P; Ward, D R; Watabe, M; Webb, R C; Weber, A; Wehmann, A; West, N; White, C; White, R F; Wojcicki, S G; Wright, D M; Wu, Q K; Yan, W G; Yang, T; Yumiceva, F X; Yun, J C; Zheng, H; Zois, M; Zwaska, R

    2006-01-01

    The complete 5.4 kton MINOS far detector has been taking data since the beginning of August 2003 at a depth of 2070 meters water-equivalent in the Soudan mine, Minnesota. This paper presents the first MINOS observations of muon neutrino and muon anti-neutrino charged-current atmospheric neutrino interactions based on an exposure of 418 days. The ratio of upward to downward-going events in the data is compared to the Monte Carlo expectation in the absence of neutrino oscillations giving: R_data(up/down)/R_MC(up/down) = 0.62^{+0.19}_{-0.14} (stat.) +- 0.02 (sys.). An extended maximum likelihood analysis of the observed L/E distributions excludes the null hypothesis of no neutrino oscillations at the 98 % confidence level. Using the curvature of the observed muons in the 1.3 T MINOS magnetic field muon neutrino and muon anti-neutrino interactions are separated. The ratio of muon neutrino to muon anti-neutrino events in the data is compared to the Monte Carlo expectation assuming neutrinos and anti-neutrinos osci...

  14. Selected aspects of fusion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, D

    2003-01-01

    In this lecture, we present selected aspects of nuclear fusion. The importance of the initial geometry of the reaction and its relation to fusion barrier are first discussed. The effect of deformation leading to the notion of barrier distribution is then illustrated. After a brief overview of the advantages of macroscopic theories, the dynamics of nuclear system under large amplitude motion is reviewed. The di-nuclear concept is presented to understand the competition between fusion and quasi-fission. This concept is then generalized to account for the dissipative dynamics in multidimensional collective space. The last part of this lecture is devoted to new aspects encountered with radioactive beams specific properties of very extended neutron rich system, influence of pygmy or soft dipole resonances and charge exchange far from stability are discussed. (author)

  15. Measurement of muon neutrino and antineutrino induced single neutral pion production cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Colin E. [Yale Univ., New Haven, CT (United States)

    2011-05-01

    Elucidating the nature of neutrino oscillation continues to be a goal in the vanguard of the efforts of physics experiment. As neutrino oscillation searches seek an increasingly elusive signal, a thorough understanding of the possible backgrounds becomes ever more important. Measurements of neutrino-nucleus interaction cross sections are key to this understanding. Searches for νμ → νe oscillation - a channel that may yield insight into the vanishingly small mixing parameter θ13, CP violation, and the neutrino mass hierarchy - are particularly susceptible to contamination from neutral current single π0 (NC 1π0) production. Unfortunately, the available data concerning NC 1π0 production are limited in scope and statistics. Without satisfactory constraints, theoretical models of NC 1π0 production yield substantially differing predictions in the critical Eν ~ 1 GeV regime. Additional investigation of this interaction can ameliorate the current deficiencies. The Mini Booster Neutrino Experiment (MiniBooNE) is a short-baseline neutrino oscillation search operating at the Fermi National Accelerator Laboratory (Fermilab). While the oscillation search is the principal charge of the MiniBooNE collaboration, the extensive data (~ 106 neutrino events) offer a rich resource with which to conduct neutrino cross section measurements. This work concerns the measurement of both neutrino and antineutrino NC 1π0 production cross sections at MiniBooNE. The size of the event samples used in the analysis exceeds that of all other similar experiments combined by an order of magnitude. We present the first measurements of the absolute NC 1π0 cross section as well as the first differential cross sections in both neutrino and antineutrino mode. Specifically, we measure single differential cross sections with respect to pion momentum and pion angle. We find the

  16. Measurement of muon neutrino and antineutrino induced single neutral pion production cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Colin; /Yale U.

    2010-12-01

    Elucidating the nature of neutrino oscillation continues to be a goal in the vanguard of the efforts of physics experiment. As neutrino oscillation searches seek an increasingly elusive signal, a thorough understanding of the possible backgrounds becomes ever more important. Measurements of neutrino-nucleus interaction cross sections are key to this understanding. Searches for {nu}{sub {mu}} {yields} {nu}{sub e} oscillation - a channel that may yield insight into the vanishingly small mixing parameter {theta}{sub 13}, CP violation, and the neutrino mass hierarchy - are particularly susceptible to contamination from neutral current single {pi}{sup 0} (NC 1{pi}{sup 0}) production. Unfortunately, the available data concerning NC 1{pi}{sup 0} production are limited in scope and statistics. Without satisfactory constraints, theoretical models of NC 1{pi}{sup 0} production yield substantially differing predictions in the critical E{sub {nu}} {approx} 1 GeV regime. Additional investigation of this interaction can ameliorate the current deficiencies. The Mini Booster Neutrino Experiment (MiniBooNE) is a short-baseline neutrino oscillation search operating at the Fermi National Accelerator Laboratory (Fermilab). While the oscillation search is the principal charge of the MiniBooNE collaboration, the extensive data ({approx} 10{sup 6} neutrino events) offer a rich resource with which to conduct neutrino cross section measurements. This work concerns the measurement of both neutrino and antineutrino NC 1{pi}{sup 0} production cross sections at MiniBooNE. The size of the event samples used in the analysis exceeds that of all other similar experiments combined by an order of magnitude. We present the first measurements of the absolute NC 1{pi}{sup 0} cross section as well as the first differential cross sections in both neutrino and antineutrino mode. Specifically, we measure single differential cross sections with respect to pion momentum and pion angle. We find the flux

  17. Method of Fission Product Beta Spectra Measurements for Predicting Reactor Anti-neutrino Emission

    CERN Document Server

    Asner, D M; Campbell, L W; Greenfield, B; Kos, M S; Orrell, J L; Schram, M; VanDevender, B; Wood, 1 L S; Wootan, D W

    2014-01-01

    The nuclear fission process that occurs in the core of nuclear reactors results in unstable, neutron rich fission products that subsequently beta decay and emit electron anti-neutrinos. These reactor neutrinos have served neutrino physics research from the initial discovery of the neutrino to current precision measurements of neutrino mixing angles. The prediction of the absolute flux and energy spectrum of the emitted reactor neutrinos hinges upon a series of seminal papers based on measurements performed in the 1970s and 1980s. The steadily improving reactor neutrino measurement techniques and recent re-considerations of the agreement between the predicted and observed reactor neutrino flux motivates revisiting the underlying beta spectra measurements. A method is proposed to use an accelerator proton beam delivered to an engineered target to yield a neutron field tailored to reproduce the neutron energy spectrum present in the core of an operating nuclear reactor. Foils of the primary reactor fissionable i...

  18. Measurement of Muon Antineutrino Quasi-Elastic Scattering on a Hydrocarbon Target at E_{\

    CERN Document Server

    Fields, L; Aliaga, L; Altinok, O; Bodek, A; Boehnlein, D; Bradford, R; Brooks, W K; Budd, H; Butkevich, A; Caicedo, D A M; Castromonte, C M; Christy, M E; da Motta, H; Damiani, D S; Danko, I; Datta, M; Day, M; DeMaat, R; Devan, J; Diaz, G A; Dytman, S A; Eberly, B; Edmondson, D A; Felix, J; Fitzpatrick, T; Fiorentini, G A; Gago, A M; Gallagher, H; Gobbi, B; Gran, R; Harris, D A; Higuera, A; Howley, I J; Hurtado, K; Jerkins, M; Kafka, T; Kanter, M O; Keppel, C; Kordosky, M; Krajeski, A H; Kulagin, S A; Le, T; Leister, A G; Maggi, G; Maher, E; Manly, S; Mann, W A; Marshall, C M; McFarland, K S; McGivern, C L; McGowan, A M; Mislivec, A; Morfin, J G; Mousseau, J; Naples, D; Nelson, J K; Niculescu, G; Niculescu, I; Ochoa, N; O'Connor, C D; Osta, J; Palomino, J L; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Pena, C; Rakotondravohitra, L; Ransome, R D; Ray, H; Ren, L; Rodrigues, P A; Sassin, K E; Schellman, H; Schmitz, D W; Schneider, R M; Schulte, E C; Sedita, P; Simon, C; Snider, F D; Snyder, M C; Sobczyk, J T; Salinas, C J Solano; Tagg, N; Tan, W; Tice, B G; Tzanakos, G; Velasquez, J P; Walding, J; Walton, T; Wolcott, J; Wolthuis, B A; Zavala, G; Zhang, D; Ziemer, B P

    2013-01-01

    We have isolated muon anti-neutrino charged-current quasi-elastic interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross-section, d{\\sigma}/dQ^2, and compare to several theoretical models of quasi-elastic scattering. Good agreement is obtained with a model where the nucleon axial mass, M_A, is set to 0.99 GeV/c^2 but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross-section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at higher Q^2 favor this interpretation over an alternative in which the axial mass is increased.

  19. Nuclear disintegration modes research with missing antineutrino in the Frejus detector

    International Nuclear Information System (INIS)

    The Frejus detector is a 900 tons fine grained calorimeter built in order to look for nucleon decay. It has reached a fiducial sensitivity of 1.3 kt. year after four years of data taking. In this thesis the decay modes with a missing anti-neutrino and one meson are studied. The analyses of all the meson decay channels are described, in particular those where the final state involves only photons or a muon due to K+ decay. The topological and kinematical cuts are different for all the channels; the detection efficiency computed by Monte -Carlo simulation ranges from 10% to 16%. The background is due to atmospheric neutrino interactions in the detector, and is estimated from a simulation. Data are consistent with the calculated background, which is smaller or close to one event per decay channel. Lower nucleon lifetime limits are obtained, which range from 0.9 1031 to 2.9 1031 years

  20. Neutrino Spin-Flavor Conversions and Electron Antineutrino emission from the Sun with Random Magnetic Field

    CERN Document Server

    Semikoz, V B; Popov, V Yu; Rez, A I; Sokoloff, D D

    2000-01-01

    The magnetic field in the solar convective zone has a random small-scale component with the r.m.s. value substancially exceeding the strength of a regular large-scale field. For two Majorana neutrino flavors and two helicities in the presence of a neutrino transition magnetic moment and nonzero neutrino mixing we analize the displacement of the allowed (Delta m^2 - sin^2 2theta)-parameter region reconciled for all Underground experiments with solar neutrinos in dependence on the r.m.s. magnetic field value b. In contrary with the RSFP scenario with a regular large-scale magnetic field, we find an effective production of electron antineutrinos in the Sun even for small neutrino mixing through the cascade conversions like nu_eL -> \\bar{nu}_muR -> forbidden while opening LOW MSW as the allowed one from the non-observation of 100 kG and correlation lengths shorter than L_0 < 1000 km.

  1. Terrestrial matter effects on reactor antineutrino oscillations at JUNO or RENO-50: how small is small?

    CERN Document Server

    Li, Yu-Feng; Xing, Zhi-zhong

    2016-01-01

    We have carefully examined, in both analytical and numerical ways, how small the terrestrial matter effects can be in a given medium-baseline reactor antineutrino oscillation experiment like JUNO or RENO-50. Taking the ongoing JUNO experiment for example, we show that the inclusion of terrestrial matter effects may reduce the sensitivity of the neutrino mass ordering measurement by \\Delta \\chi^2_{\\rm MO} \\simeq 0.6, and a neglect of such effects may shift the best-fit values of the flavor mixing angle \\theta_{12} and the neutrino mass-squared difference \\Delta_{21} by about 1\\sigma to 2\\sigma in the future data analysis. In addition, a preliminary estimate indicates that a 2\\sigma sensitivity of establishing the terrestrial matter effects can be achieved for about 10 years of data taking at JUNO with the help of a proper near detector implementation.

  2. Calorimetric measurement of the SOX anti-neutrino source for sterile neutrino search

    Energy Technology Data Exchange (ETDEWEB)

    Altenmueller, Konrad; Agostini, Matteo; Papp, Laszlo; Schoenert, Stefan [Physik Department and Excellence Cluster Universe, Technische Universitaet Muenchen (Germany); Collaboration: Borexino-Collaboration

    2015-07-01

    A thermal calorimeter is under development to measure with <1% accuracy the heat release of the Cerium anti-neutrino source for the SOX experiment, which is looking for eV-scale sterile neutrinos. The heat release is proportional to the source activity and thus to the emitted neutrino flux, which is an important parameter of the experiment. The calorimeter design is based on a copper heat exchanger mounted around the source with integrated water lines for the heat extraction. Heat loss through conduction and radiation is minimized by suspending the set-up through Kevlar ropes and inserting it inside a thermalized vacuum tank with radiation shields. The device is currently being assembled and tested at TUM in Garching.

  3. Anharmonicity of internal atomic oscillation and effective antineutrino mass evaluation from gaseous molecular tritium \\beta -decay

    CERN Document Server

    Lokhov, Alexey V

    2016-01-01

    Data analysis of the next generation effective antineutrino mass measurement experiment KATRIN requires reliable knowledge of systematic corrections. In particular, the width of the daughter molecular ion excitation spectrum rovibrational band should be known with a better then 1% precision. Very precise ab initio quantum calculations exist, and we compare them with the well known tritium molecule parameters within the framework of a phenomenological model. The rovibrational band width with accuracy of a few percent is interpreted as a result of the zero-point atomic oscillation in the harmonic potential. The Morse interatomic potential is used to investigate the impact of anharmonic atomic oscillations. The calculated corrections cannot account for the difference between the ab initio quantum calculations and the phenomenological model.

  4. Neutrino mass bound in the standard scenario for supernova electronic antineutrino emission

    CERN Document Server

    Pagliaroli, Giulia; Vissani, Francesco

    2010-01-01

    Based on recent improvements of the supernova electron antineutrino emission model, we update the limit on neutrino mass from the SN1987A data collected by Kamiokande-II, IMB and Baksan. We derive the limit of 5.8 eV at 95 % CL, that we show to be remarkably insensitive to the astrophysical uncertainties. Also we evaluate the ultimate mass sensitivity of this method for a detector like Super-Kamiokande. We find that the bound lies in the sub-eV region, 0.8 eV at 95 % CL being a typical outcome, competitive with the values that are presently probed in laboratory. However, this bound is subject to strong statistical fluctuations, correlated to the characteristics of the first few events detected. We briefly comment on the prospects offered by future detectors.

  5. Consistent analysis of neutral- and charged-current (anti)neutrino scattering off carbon

    International Nuclear Information System (INIS)

    Good understanding of the cross sections for (anti)neutrino scattering off nuclear targets in the few-GeV energy region is a prerequisite for the correct interpretation of results of ongoing and planned oscillation experiments. To clarify a possible source of disagreement between recent measurements of the cross sections on carbon, we analyze the available data within an approach based on the realistic spectral function of carbon, treating neutral-current elastic (NCE) and charged-current quasielastic (CCQE) processes on equal footing. We show that the axial mass from the shape analysis of the MiniBooNE data is in good agreement with the results reported by the BNL E734 and NOMAD Collaborations. However, the combined analysis of the NCE and CCQE data does not seem to support the contribution of multinucleon final states being large enough to explain the normalization of the MiniBooNE-reported cross sections

  6. Consistent analysis of neutral- and charged-current (anti)neutrino scattering off carbon

    CERN Document Server

    Ankowski, Artur M

    2013-01-01

    Good understanding of the cross sections for (anti)neutrino scattering off nuclear targets in the few-GeV energy region is a prerequisite for the correct interpretation of results of ongoing and planned oscillation experiments. To clarify a possible source of disagreement between recent measurements of the cross sections on carbon, we analyze the available data within an approach based on the realistic spectral function of carbon, treating neutral-current elastic (NCE) and charged-current quasielastic (CCQE) processes on equal footing. We show that the axial mass from the shape analysis of the MiniBooNE data is in good agreement with the results reported by the BNL E734 and NOMAD Collaborations. However, the combined analysis of the NCE and CCQE data does not seem to support the contribution of multinucleon final states being large enough to explain the normalization of the MiniBooNE-reported cross sections.

  7. Consistent analysis of neutral- and charged-current (anti)neutrino scattering off carbon

    Science.gov (United States)

    Ankowski, Artur M.

    2015-05-01

    Good understanding of the cross sections for (anti)neutrino scattering off nuclear targets in the few-GeV energy region is a prerequisite for the correct interpretation of results of ongoing and planned oscillation experiments. To clarify a possible source of disagreement between recent measurements of the cross sections on carbon, we analyze the available data within an approach based on the realistic spectral function of carbon, treating neutral-current elastic (NCE) and charged-current quasielastic (CCQE) processes on equal footing. We show that the axial mass from the shape analysis of the MiniBooNE data is in good agreement with the results reported by the BNL E734 and NOMAD Collaborations. However, the combined analysis of the NCE and CCQE data does not seem to support the contribution of multinucleon final states being large enough to explain the normalization of the MiniBooNE-reported cross sections.

  8. Consistent analysis of neutral- and charged-current (anti)neutrino scattering off carbon

    Energy Technology Data Exchange (ETDEWEB)

    Ankowski, Artur M. [INFN and Department of Physics,“Sapienza” Università di Roma, I-00185 Roma (Italy)

    2015-05-15

    Good understanding of the cross sections for (anti)neutrino scattering off nuclear targets in the few-GeV energy region is a prerequisite for the correct interpretation of results of ongoing and planned oscillation experiments. To clarify a possible source of disagreement between recent measurements of the cross sections on carbon, we analyze the available data within an approach based on the realistic spectral function of carbon, treating neutral-current elastic (NCE) and charged-current quasielastic (CCQE) processes on equal footing. We show that the axial mass from the shape analysis of the MiniBooNE data is in good agreement with the results reported by the BNL E734 and NOMAD Collaborations. However, the combined analysis of the NCE and CCQE data does not seem to support the contribution of multinucleon final states being large enough to explain the normalization of the MiniBooNE-reported cross sections.

  9. Around the laboratories: Dubna: Physics results and progress on bubble chamber techniques; Stanford (SLAC): Operation of a very rapid cycling bubble chamber; Daresbury: Photographs of visitors to the Laboratory; Argonne: Charge exchange injection tests into the ZGS in preparation for a proposed Booster

    CERN Multimedia

    1969-01-01

    Around the laboratories: Dubna: Physics results and progress on bubble chamber techniques; Stanford (SLAC): Operation of a very rapid cycling bubble chamber; Daresbury: Photographs of visitors to the Laboratory; Argonne: Charge exchange injection tests into the ZGS in preparation for a proposed Booster

  10. Detection of Anomalous Reactor Activity Using Antineutrino Count Rate Evolution Over the Course of a Reactor Cycle

    CERN Document Server

    Bulaevskaya, Vera

    2010-01-01

    This paper analyzes the sensitivity of antineutrino count rate measurements to changes in the fissile content of civil power reactors. Such measurements may be useful in IAEA reactor safeguards applications. We introduce a hypothesis testing procedure to identify statistically significant differences between the antineutrino count rate evolution of a standard 'baseline' fuel cycle and that of an anomalous cycle, in which plutonium is removed and replaced with an equivalent fissile worth of uranium. The test would allow an inspector to detect anomalous reactor activity, or to positively confirm that the reactor is operating in a manner consistent with its declared fuel inventory and power level. We show that with a reasonable choice of detector parameters, the test can detect replacement of 73 kg of plutonium in 90 days with 95% probability, while controlling the false positive rate at 5%. We show that some improvement on this level of sensitivity may be expected by various means, including use of the method i...

  11. Preliminary study of the 19F(7Li,7Be)19O reaction at 52 MeV with MAGNEX

    CERN Document Server

    Cavallaro, M; Cappuzzello, F; Carbone, D; Foti, A; Orrigo, S E A; Rodrigues, M R D; Schillaci, M; Borello-Lewin, T; Petrascu, H

    2010-01-01

    The 19F(7Li,7Be)19O charge-exchange reaction at 52 MeV incident energy has been performed at INFN-LNS in Catania using the MAGNEX spectrometer. The use of an algebraic ray-reconstruction technique has allowed to extract the 19O excitation energy spectrum and the experimental angular distributions obtained with a single angular setting of the spectrometer.

  12. A feasibility study of boron-loaded liquid scintillator for the detection of electron anti-neutrinos

    CERN Document Server

    Wang, S C; Leung, R W S; Wang, S L; Chang, C Y; Chen Chi Ping; Cheng, K C; Ho, T I; Lai, W P; Liu, H M; Mao, Z P; Shih, I C; Wong, H T; Yu, Z Q

    1999-01-01

    Boron-loaded liquid scintillator offers some potential advantages as a detector for electron anti-neutrinos. A research program was carried out with the objective of developing such scintillators. The crucial feature is the pulse shape discrimination properties following the neutron capture by sup 1 sup 0 B. Results of the R and D efforts are presented. The feasibility and the technical difficulties of carrying out a full-scale neutrino experiment based on this approach are discussed. (author)

  13. Acrylic Target Vessels for a High-Precision Measurement of theta13 with the Daya Bay Antineutrino Detectors

    CERN Document Server

    Band, H R; Cherwinka, J; Cao, J; Chang, Y; Edwards, B; He, W; Heeger, K M; Heng, Y; Ho, T; Hsiung, B; Greenler, L; Kettell, S; Lewis, C; Luk, K B; Li, X; Littlejohn, B R; Pagac, A; Wang, C H; Wang, W; Wang, Y; Wise, T; Xiao, Q; Yeh, M; Zhuang, H

    2012-01-01

    This paper describes in detail the acrylic target vessels used to encapsulate the target and gamma catcher regions in the Daya Bay experiment's first pair of antineutrino detectors. We give an overview of the design, fabrication, shipping, and installation of the acrylic target vessels and their liquid overflow tanks. The acrylic quality assurance program and vessel characterization, which measures all geometric, optical, and material properties relevant to {\

  14. Geneva University: Observation of electron-antineutrino disappearance at Daya Bay

    CERN Multimedia

    Université de Genève

    2012-01-01

    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92 Monday 19 March 2012 COLLOQUE DE PHYSIQUE 5 p.m. - École de Physique, Auditoire Stueckelberg Observation of electron-antineutrino disappearance at Daya Bay  Professor Yifang Wang Institute of High Energy Physics of the Chinese Academy of Sciences Beijing The Daya Bay Reactor Neutrino Experiment, a multinational collaboration operating in the south of China, today reported the first results of its search for the last, most elusive piece of a long-standing puzzle: how is it that neutrinos can appear to vanish as they travel? The surprising answer opens a gateway to a new understanding of fundamental physics and may eventually solve the riddle of why there is far more ordinary matter than antimatter in the Universe today....

  15. Measurement of neutrino and antineutrino oscillations using beam and atmospheric data in MINOS.

    Science.gov (United States)

    Adamson, P; Anghel, I; Backhouse, C; Barr, G; Bishai, M; Blake, A; Bock, G J; Bogert, D; Cao, S V; Castromonte, C M; Childress, S; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; de Jong, J K; Devan, A V; Devenish, N E; Diwan, M V; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Frohne, M V; Gallagher, H R; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grzelak, K; Habig, A; Hahn, S R; Hartnell, J; Hatcher, R; Himmel, A; Holin, A; Hylen, J; Irwin, G M; Isvan, Z; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kordosky, M; Kreymer, A; Lang, K; Ling, J; Litchfield, P J; Lucas, P; Mann, W A; Marshak, M L; Mathis, M; Mayer, N; McGowan, A M; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Michael, D G; Miller, W H; Mishra, S R; Moed Sher, S; Moore, C D; Mualem, L; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; O'Connor, J; Oliver, W P; Orchanian, M; Pahlka, R B; Paley, J; Patterson, R B; Pawloski, G; Phan-Budd, S; Plunkett, R K; Qiu, X; Radovic, A; Rebel, B; Rosenfeld, C; Rubin, H A; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Tinti, G; Tognini, S C; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Weber, A; Webb, R C; White, C; Whitehead, L; Whitehead, L H; Wojcicki, S G; Zwaska, R

    2013-06-21

    We report measurements of oscillation parameters from ν(μ) and ν(μ) disappearance using beam and atmospheric data from MINOS. The data comprise exposures of 10.71×10(20) protons on target in the ν(μ)-dominated beam, 3.36×10(20) protons on target in the ν(μ)-enhanced beam, and 37.88 kton yr of atmospheric neutrinos. Assuming identical ν and ν oscillation parameters, we measure |Δm2| = (2.41(-0.10)(+0.09))×10(-3)  eV2 and sin2(2θ) = 0.950(-0.036)(+0.035). Allowing independent ν and ν oscillations, we measure antineutrino parameters of |Δm2| = (2.50(-0.25)(+0.23))×10(-3)  eV2 and sin2(2θ) = 0.97(-0.08)(+0.03), with minimal change to the neutrino parameters. PMID:23829728

  16. Earth Radioactivity Measurements with a Deep Ocean Anti-neutrino Observatory

    CERN Document Server

    Dye, S T; Learned, J G; Maricic, J; Matsuno, S; Pakvasa, S; Varner, G; Wilcox, M

    2006-01-01

    We consider the detector size, location, depth, backgrounds, and radio-purity required of a mid-Pacific deep-ocean instrument to accomplish the twin goals of making a definitive measurement of the electron anti-neutrino flux due to uranium and thorium decays from Earth's mantle and core, and of testing the hypothesis for a natural nuclear reactor at the core of Earth. We take the experience with the KamLAND detector in Japan as our baseline for sensitivity and background estimates. We conclude that an instrument adequate to accomplish these tasks should have an exposure of at least 10 kilotonne-years (kT-y), should be placed at least at 4 km depth, may be located close to the Hawaiian Islands (no significant background from them), and should aim for KamLAND radio-purity levels, except for radon where it should be improved by a factor of at least 40. With an exposure of 10 kT-y we should achieve a 24% measurement of the U/Th content of the mantle plus core. Exposure at multiple ocean locations for testing late...

  17. Measurement of neutrino and antineutrino oscillations using beam and atmospheric data in MINOS.

    Science.gov (United States)

    Adamson, P; Anghel, I; Backhouse, C; Barr, G; Bishai, M; Blake, A; Bock, G J; Bogert, D; Cao, S V; Castromonte, C M; Childress, S; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; de Jong, J K; Devan, A V; Devenish, N E; Diwan, M V; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Frohne, M V; Gallagher, H R; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grzelak, K; Habig, A; Hahn, S R; Hartnell, J; Hatcher, R; Himmel, A; Holin, A; Hylen, J; Irwin, G M; Isvan, Z; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kordosky, M; Kreymer, A; Lang, K; Ling, J; Litchfield, P J; Lucas, P; Mann, W A; Marshak, M L; Mathis, M; Mayer, N; McGowan, A M; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Michael, D G; Miller, W H; Mishra, S R; Moed Sher, S; Moore, C D; Mualem, L; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; O'Connor, J; Oliver, W P; Orchanian, M; Pahlka, R B; Paley, J; Patterson, R B; Pawloski, G; Phan-Budd, S; Plunkett, R K; Qiu, X; Radovic, A; Rebel, B; Rosenfeld, C; Rubin, H A; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Tinti, G; Tognini, S C; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Weber, A; Webb, R C; White, C; Whitehead, L; Whitehead, L H; Wojcicki, S G; Zwaska, R

    2013-06-21

    We report measurements of oscillation parameters from ν(μ) and ν(μ) disappearance using beam and atmospheric data from MINOS. The data comprise exposures of 10.71×10(20) protons on target in the ν(μ)-dominated beam, 3.36×10(20) protons on target in the ν(μ)-enhanced beam, and 37.88 kton yr of atmospheric neutrinos. Assuming identical ν and ν oscillation parameters, we measure |Δm2| = (2.41(-0.10)(+0.09))×10(-3)  eV2 and sin2(2θ) = 0.950(-0.036)(+0.035). Allowing independent ν and ν oscillations, we measure antineutrino parameters of |Δm2| = (2.50(-0.25)(+0.23))×10(-3)  eV2 and sin2(2θ) = 0.97(-0.08)(+0.03), with minimal change to the neutrino parameters.

  18. Supernova neutrinos and antineutrinos: ternary luminosity diagram and spectral split patterns

    International Nuclear Information System (INIS)

    In core-collapse supernovae, the νe and ν-bar e species may experience collective flavor swaps to non-electron species νx, within energy intervals limited by relatively sharp boundaries (''splits''). These phenomena appear to depend sensitively upon the initial energy spectra and luminosities. We investigate the effect of generic variations of the fractional luminosities (le, lē, lx) with respect to the usual ''energy equipartition'' case (1/6, 1/6, 1/6), within an early-time supernova scenario with fixed thermal spectra and total luminosity. We represent the constraint le+lē+4lx = 1 in a ternary diagram, which is explored via numerical experiments (in single-angle approximation) over an evenly-spaced grid of points. In inverted hierarchy, single splits arise in most cases, but an abrupt transition to double splits is observed for a few points surrounding the equipartition one. In normal hierarchy, collective effects turn out to be unobservable at all grid points but one, where single splits occur. Admissible deviations from equipartition may thus induce dramatic changes in the shape of supernova (anti)neutrino spectra. The observed patterns are interpreted in terms of initial flavor polarization vectors (defining boundaries for the single/double split transitions), lepton number conservation, and minimization of potential energy

  19. First Anti-neutrino Oscillation Results from the T2K Experiment

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Neutrinos are some of the most abundant but yet most elusive particles in the universe. They have almost no mass, only interact weakly and relatively little is known about their properties. Furthermore it has been firmly established over the last decade that neutrinos can undergo flavour transitions as mass and flavor eigenstates are not identical. These neutrino oscillations have been studied using natural sources as well as nuclear reactors or with neutrinos produced at accelerators. T2K is a long baseline neutrino oscillation beam that uses a beam of muon (anti-)neutrinos that is directed form J-PARC at the east cost of Japan over a distance of almost 300 km to the SuperKamiokande water Cherenkov detector in the west. The facility is complemented by a near detector complex 280 m downstream of the neutrino production target to characterise the beam and the neutrino interaction dynamics. T2K has taken data with a muon neutrino beam since early 2010 and is studying the disappearance of muon neutrinos as well...

  20. Neutrino-antineutrino Mass Splitting in the Standard Model: Neutrino Oscillation and Baryogenesis

    CERN Document Server

    Fujikawa, Kazuo

    2015-01-01

    By adding a neutrino mass term to the Standard Model, which is Lorentz and $SU(2)\\times U(1)$ invariant but non-local to evade $CPT$ theorem, it is shown that non-locality within a distance scale of the Planck length, that may not be fatal to unitarity in generic effective theory, can generate the neutrino-antineutrino mass splitting of the order of observed neutrino mass differences, which is tested in oscillation experiments, and non-negligible baryon asymmetry depending on the estimate of sphaleron dynamics. The one-loop order induced electron-positron mass splitting in the Standard Model is shown to be finite and estimated at $\\sim 10^{-20}$ eV, well below the experimental bound $< 10^{-2}$ eV. The induced $CPT$ violation in the $K$-meson in the Standard Model is expected to be even smaller and well below the experimental bound $|m_{K}-m_{\\bar{K}}|<0.44\\times 10^{-18}$ GeV.

  1. Method of fission product beta spectra measurements for predicting reactor anti-neutrino emission

    Energy Technology Data Exchange (ETDEWEB)

    Asner, David M.; Burns, Kimberly A.; Campbell, Luke W.; Greenfield, Bryce A.; Kos, Marek S.; Orrell, John L.; Schram, Malachi; VanDevender, Brent A.; Wood, Lynn S.; Wootan, David W.

    2015-03-01

    The nuclear fission process that occurs in the core of nuclear reactors results in unstable, neutron-rich fission products that subsequently beta decay and emit electron antineutrinos. These reactor neutrinos have served neutrino physics research from the initial discovery of the neutrino to today's precision measurements of neutrino mixing angles. The prediction of the absolute flux and energy spectrum of the emitted reactor neutrinos hinges upon a series of seminal papers based on measurements performed in the 1970s and 1980s. The steadily improving reactor neutrino measurement techniques and recent reconsiderations of the agreement between the predicted and observed reactor neutrino flux motivates revisiting the underlying beta spectra measurements. A method is proposed to use an accelerator proton beam delivered to an engineered target to yield a neutron field tailored to reproduce the neutron energy spectrum present in the core of an operating nuclear reactor. Foils of the primary reactor fissionable isotopes placed in this tailored neutron flux will ultimately emit beta particles from the resultant fission products. Measurement of these beta particles in a time projection chamber with a perpendicular magnetic field provides a distinctive set of systematic considerations for comparison to the original seminal beta spectra measurements. Ancillary measurements such as gamma-ray emission and post-irradiation radiochemical analysis will further constrain the absolute normalization of beta emissions per fission. The requirements for unfolding the beta spectra measured with this method into a predicted reactor neutrino spectrum are explored.

  2. Data processing and storage in the Daya Bay Reactor Antineutrino Experiment

    CERN Document Server

    He, Miao

    2015-01-01

    The Daya Bay Reactor Antineutrino Experiment reported the first observation of the non-zero neutrino mixing angle $\\theta_{13}$ using the first 55 days of data. It has also provided the most precise measurement of $\\theta_{13}$ with the extended data to 621 days. Daya Bay will keep running for another 3 years or so. There is about 100 TB raw data produced per year, as well as several copies of reconstruction data with similar volume to the raw data for each copy. The raw data is transferred to Daya Bay onsite and two offsite clusters: IHEP in Beijing and LBNL in California, with a short latency. There is quasi-real-time data processing at both onsite and offsite clusters, for the purpose of data quality monitoring, detector calibration and preliminary data analyses. The physics data production took place a couple of times per year according to the physics analysis plan. This paper will introduce the data movement and storage, data processing and monitoring, and the automation of the calibration.

  3. Measurement of Muon Antineutrino Oscillations with an Accelerator-Produced Off-Axis Beam.

    Science.gov (United States)

    Abe, K; Andreopoulos, C; Antonova, M; Aoki, S; Ariga, A; Assylbekov, S; Autiero, D; Barbi, M; Barker, G J; Barr, G; Bartet-Friburg, P; Batkiewicz, M; Bay, F; Berardi, V; Berkman, S; Bhadra, S; Blondel, A; Bolognesi, S; Bordoni, S; Boyd, S B; Brailsford, D; Bravar, A; Bronner, C; Buizza Avanzini, M; Calland, R G; Cao, S; Caravaca Rodríguez, J; Cartwright, S L; Castillo, R; Catanesi, M G; Cervera, A; Cherdack, D; Chikuma, N; Christodoulou, G; Clifton, A; Coleman, J; Collazuol, G; Cremonesi, L; Dabrowska, A; De Rosa, G; Dealtry, T; Denner, P F; Dennis, S R; Densham, C; Dewhurst, D; Di Lodovico, F; Di Luise, S; Dolan, S; Drapier, O; Duffy, K E; Dumarchez, J; Dytman, S; Dziewiecki, M; Emery-Schrenk, S; Ereditato, A; Feusels, T; Finch, A J; Fiorentini, G A; Friend, M; Fujii, Y; Fukuda, D; Fukuda, Y; Furmanski, A P; Galymov, V; Garcia, A; Giffin, S G; Giganti, C; Gizzarelli, F; Gonin, M; Grant, N; Hadley, D R; Haegel, L; Haigh, M D; Hamilton, P; Hansen, D; Hara, T; Hartz, M; Hasegawa, T; Hastings, N C; Hayashino, T; Hayato, Y; Helmer, R L; Hierholzer, M; Hillairet, A; Himmel, A; Hiraki, T; Hirota, S; Hogan, M; Holeczek, J; Horikawa, S; Hosomi, F; Huang, K; Ichikawa, A K; Ieki, K; Ikeda, M; Imber, J; Insler, J; Intonti, R A; Irvine, T J; Ishida, T; Ishii, T; Iwai, E; Iwamoto, K; Izmaylov, A; Jacob, A; Jamieson, B; Jiang, M; Johnson, S; Jo, J H; Jonsson, P; Jung, C K; Kabirnezhad, M; Kaboth, A C; Kajita, T; Kakuno, H; Kameda, J; Karlen, D; Karpikov, I; Katori, T; Kearns, E; Khabibullin, M; Khotjantsev, A; Kielczewska, D; Kikawa, T; Kim, H; Kim, J; King, S; Kisiel, J; Knight, A; Knox, A; Kobayashi, T; Koch, L; Koga, T; Konaka, A; Kondo, K; Kopylov, A; Kormos, L L; Korzenev, A; Koshio, Y; Kropp, W; Kudenko, Y; Kurjata, R; Kutter, T; Lagoda, J; Lamont, I; Larkin, E; Laveder, M; Lawe, M; Lazos, M; Lindner, T; Liptak, Z J; Litchfield, R P; Li, X; Longhin, A; Lopez, J P; Ludovici, L; Lu, X; Magaletti, L; Mahn, K; Malek, M; Manly, S; Marino, A D; Marteau, J; Martin, J F; Martins, P; Martynenko, S; Maruyama, T; Matveev, V; Mavrokoridis, K; Ma, W Y; Mazzucato, E; McCarthy, M; McCauley, N; McFarland, K S; McGrew, C; Mefodiev, A; Mezzetto, M; Mijakowski, P; Minamino, A; Mineev, O; Mine, S; Missert, A; Miura, M; Moriyama, S; Mueller, Th A; Murphy, S; Myslik, J; Nakadaira, T; Nakahata, M; Nakamura, K G; Nakamura, K; Nakamura, K D; Nakayama, S; Nakaya, T; Nakayoshi, K; Nantais, C; Nielsen, C; Nirkko, M; Nishikawa, K; Nishimura, Y; Nowak, J; O'Keeffe, H M; Ohta, R; Okumura, K; Okusawa, T; Oryszczak, W; Oser, S M; Ovsyannikova, T; Owen, R A; Oyama, Y; Palladino, V; Palomino, J L; Paolone, V; Patel, N D; Pavin, M; Payne, D; Perkin, J D; Petrov, Y; Pickard, L; Pickering, L; Pinzon Guerra, E S; Pistillo, C; Popov, B; Posiadala-Zezula, M; Poutissou, J-M; Poutissou, R; Przewlocki, P; Quilain, B; Radicioni, E; Ratoff, P N; Ravonel, M; Rayner, M A M; Redij, A; Reinherz-Aronis, E; Riccio, C; Rojas, P; Rondio, E; Roth, S; Rubbia, A; Rychter, A; Sacco, R; Sakashita, K; Sánchez, F; Sato, F; Scantamburlo, E; Scholberg, K; Schoppmann, S; Schwehr, J; Scott, M; Seiya, Y; Sekiguchi, T; Sekiya, H; Sgalaberna, D; Shah, R; Shaikhiev, A; Shaker, F; Shaw, D; Shiozawa, M; Shirahige, T; Short, S; Smy, M; Sobczyk, J T; Sorel, M; Southwell, L; Stamoulis, P; Steinmann, J; Stewart, T; Suda, Y; Suvorov, S; Suzuki, A; Suzuki, K; Suzuki, S Y; Suzuki, Y; Tacik, R; Tada, M; Takahashi, S; Takeda, A; Takeuchi, Y; Tanaka, H K; Tanaka, H A; Terhorst, D; Terri, R; Thakore, T; Thompson, L F; Tobayama, S; Toki, W; Tomura, T; Touramanis, C; Tsukamoto, T; Tzanov, M; Uchida, Y; Vacheret, A; Vagins, M; Vallari, Z; Vasseur, G; Wachala, T; Wakamatsu, K; Walter, C W; Wark, D; Warzycha, W; Wascko, M O; Weber, A; Wendell, R; Wilkes, R J; Wilking, M J; Wilkinson, C; Wilson, J R; Wilson, R J; Yamada, Y; Yamamoto, K; Yamamoto, M; Yanagisawa, C; Yano, T; Yen, S; Yershov, N; Yokoyama, M; Yoo, J; Yoshida, K; Yuan, T; Yu, M; Zalewska, A; Zalipska, J; Zambelli, L; Zaremba, K; Ziembicki, M; Zimmerman, E D; Zito, M; Żmuda, J

    2016-05-01

    T2K reports its first measurements of the parameters governing the disappearance of ν[over ¯]_{μ} in an off-axis beam due to flavor change induced by neutrino oscillations. The quasimonochromatic ν[over ¯]_{μ} beam, produced with a peak energy of 0.6 GeV at J-PARC, is observed at the far detector Super-Kamiokande, 295 km away, where the ν[over ¯]_{μ} survival probability is expected to be minimal. Using a data set corresponding to 4.01×10^{20} protons on target, 34 fully contained μ-like events were observed. The best-fit oscillation parameters are sin^{2}(θ[over ¯]_{23})=0.45 and |Δm[over ¯]_{32}^{2}|=2.51×10^{-3}  eV^{2} with 68% confidence intervals of 0.38-0.64 and 2.26-2.80×10^{-3}  eV^{2}, respectively. These results are in agreement with existing antineutrino parameter measurements and also with the ν_{μ} disappearance parameters measured by T2K. PMID:27203315

  4. Electromagnetic and weak form factors of nucleon and charged quasielastic scatterings of neutrino (antineutrino) and nucleon

    CERN Document Server

    Li, Bing An

    2014-01-01

    The study of electromagnetic and weak form factors of nucleon (charged quasielastic scatterings of neutrino (antineutrino) and nucleon) done in $70^\\prime s$ and published in Chinese journals is reviewed. In the approach of the study antiquark components are introduced to the wave functions of nucleon and the study shows that the antiquark components of nucleon play an essential role in the EM and weak form factors of nucleon. The SU(6) symmetric wave functions of baryons in the rest frame ( s-wave in the rest frame) have been constructed. In these wave functions there are both quark and antiquark components. Using Lorentz transformations these wave functions are boosted to moving frame. In terms of effective Lagrangian these wave functions are used to study the EM and weak form factors of nucleon and $p \\rightarrow \\Delta$. The ratio $\\mu_p G^p_E/G^p_M$, $G^n_E$, $G^n_M$, $G^*_M$, $E1+$ and $S1+$ of $p \\rightarrow \\Delta$ are predicted. The axial-vector form factors of nucleon is predicted to be $G_A(q^2)/G_...

  5. The diffuse neutrino flux from supernovae: upper limit on the electron neutrino component from the non-observation of antineutrinos at SuperKamiokande

    CERN Document Server

    Lunardini, C

    2006-01-01

    I derive an upper bound on the electron neutrino component of the diffuse supernova neutrino flux from the constraint on the antineutrino component at SuperKamiokande. The connection between antineutrino and neutrino channels is due to the similarity of the muon and tau neutrino and antineutrino fluxes produced in a supernova, and to the conversion of these species into electron neutrinos and antineutrinos inside the star. The limit on the electron neutrino flux is 5.5 cm^-2 s^-1 above 19.3 MeV of neutrino energy, and is stronger than the direct limit from LSD by three orders of magnitude. It represents the minimal sensitivity required at future direct searches, and is intriguingly close to the reach of the SNO and ICARUS experiments. The electron neutrino flux will have a lower bound if the electron antineutrino flux is measured. Indicatively, the first can be smaller than the second at most by a factor of 2-3 depending on the details of the neutrino spectra at production.

  6. Grazing incidence collisions of ions and atoms with surfaces: from charge exchange to atomic diffraction; Collisions rasantes d'ions ou d'atomes sur les surfaces: de l'echange de charge a la diffraction atomique

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, P

    2006-09-15

    This thesis reports two studies about the interaction with insulating surfaces of keV ions or atoms under grazing incidence. The first part presents a study of charge exchange processes occurring during the interaction of singly charged ions with the surface of NaCl. In particular, by measuring the scattered charge fraction and the energy loss in coincidence with electron emission, the neutralization mechanism is determined for S{sup +}, C{sup +}, Xe{sup +}, H{sup +}, O{sup +}, Kr{sup +}, N{sup +}, Ar{sup +}, F{sup +}, Ne{sup +} and He{sup +}. These results show the importance of the double electron capture as neutralization process for ions having too much potential energy for resonant capture and not enough for Auger neutralization. We have also studied the ionisation of the projectile and of the surface, and the different Auger-like neutralization processes resulting in electron emission, population of conduction band or excited state. For oxygen scattering, we have measured an higher electron yield in coincidence with scattered negative ion than with scattered atom suggesting the transient formation above the surface of the oxygen doubly negative ion. The second study deals with the fast atom diffraction, a new phenomenon observed for the first time during this work. Due to the large parallel velocity, the surface appears as a corrugated wall where rows interfere. Similarly to the Thermal Atom Scattering the diffraction pattern corresponds to the surface potential and is sensitive to vibrations. We have study the H-NaCl and He-LiF atom-surface potentials in the 20 meV - 1 eV range. This new method offers interesting perspectives for surface characterisation. (author)

  7. Spin transfer coefficients for the (p suprho,n suprho) reaction in the plane wave approximation

    CERN Document Server

    Lee, H S; Kim, B T

    1998-01-01

    The spin transfer coefficients D sub n sub n (theta=0 .deg. ) for the intermediate energy charge exchange reaction (p suprho,n suprho) leading to the giant resonances in the continuum region are investigated. The dependence of the spin transfer coefficients on the nuclear wave function, the reaction Q-value, and the effective two-body interaction are studied using the plane wave approximation. It is shown that both the direct and the exchange parts of the tensor interaction play important roles in determining the D sub n sub n value.

  8. Strangeness production and hypernucleus formation in antiproton induced reactions

    CERN Document Server

    Feng, Zhao-Qing

    2015-01-01

    Formation mechanism of fragments with strangeness in collisions of antiprotons on nuclei has been investigated within the Lanzhou quantum molecular dynamics (LQMD) transport approach combined with a statistical model (GEMINI) for describing the decays of excited fragments. Production of strange particles in the antiproton induced nuclear reactions is modeled within the LQMD model, in which all possible reaction channels such as elastic scattering, annihilation, charge exchange and inelastic scattering in antibaryon-baryon, baryon-baryon and meson-baryon collisions have been included. A coalescence approach is developed for constructing hyperfragments in phase space after de-excitation of nucleonic fragments. The combined approach could describe the production of fragments in low-energy antiproton induced reactions. Hyperfragments are formed within the narrower rapidities and lower kinetic energies. It has advantage to produce heavier hyperfragments and hypernuclides with strangeness s=-2 (double-$\\Lambda$ fra...

  9. Global Analysis of the Source and Detector Nonstandard Interactions Using the Short Baseline Neutrino- and Antineutrino-Electron Scattering Data

    CERN Document Server

    Khan, Amir N

    2016-01-01

    We present a global analysis of the semileptonic and purely Leptonic nonuniversal and flavor-changing nonstandard neutrino interactions in all the known short-baseline neutrino- and antineutrino-electron scattering experiments. The nonstandard effects at the source and at the detector can be more transparent in these experiments because of the negligibly small ratio between the baselines and the neutrino energies, which is not enough for the neutrinos to oscillate, and thus can be sensitive to the new physics at the both ends. We use data from two electron-neutrino electron scattering experiments and six electron-antineutrino electron scattering experiments and combine them to find the best fits on the nonstandard parameters using the source-only, detector-only analyses, and then find the interplay between the two cases. The bounds obtained in some cases are stronger and new, in some cases comparable to the current ones, and in the other cases weaker. For instance, the bound obtained from the interplay betwee...

  10. Messung der Impulsverteilung der Antiquarks im Nukleon aus der inklusiven tiefinelastischen Antineutrino Nukleon Reaktion ueber geladene Stroeme

    CERN Document Server

    Klasen, Hans Peter

    1981-01-01

    In this thesis the antiquark momentum distribution in the nucleus as a function of x and Q2 is determined. This determination is based on the measurement of the differential cross-section at high y for inclusive antineutrino nucleon charged current interactions. The portion of antineutrino scattering off quarks is corrected by the also measured neutrino cross-section. For the measurement of the cross-section 150 000 anti v- und 35 000 v-events, which were produced in the CERN wide band beam, in the energy range from 20 GeV to 160 GeV and 27 000 anti v- and 63 000 v-events measured in the narrow band beam in the energy range from 20 GeV to 200 GeV are used. The measurement was performed with the detector of the CERN-Dortmund-Heidelberg-Saclay collaboration. The detector serves at the same time as target, as hadron energy calorimeter and as muon spectrometer. The measured antiquark momentum distribution shows a strong rise for x<0.1 as a function of Q2. It will be shown that this scaling violation cannot be ...

  11. Effects of Fission Yield Data in the Calculation of Antineutrino Spectra for ^{235}U(n,fission) at Thermal and Fast Neutron Energies.

    Science.gov (United States)

    Sonzogni, A A; McCutchan, E A; Johnson, T D; Dimitriou, P

    2016-04-01

    Fission yields form an integral part of the prediction of antineutrino spectra generated by nuclear reactors, but little attention has been paid to the quality and reliability of the data used in current calculations. Following a critical review of the thermal and fast ENDF/B-VII.1 ^{235}U fission yields, deficiencies are identified and improved yields are obtained, based on corrections of erroneous yields, consistency between decay and fission yield data, and updated isomeric ratios. These corrected yields are used to calculate antineutrino spectra using the summation method. An anomalous value for the thermal fission yield of ^{86}Ge generates an excess of antineutrinos at 5-7 MeV, a feature which is no longer present when the corrected yields are used. Thermal spectra calculated with two distinct fission yield libraries (corrected ENDF/B and JEFF) differ by up to 6% in the 0-7 MeV energy window, allowing for a basic estimate of the uncertainty involved in the fission yield component of summation calculations. Finally, the fast neutron antineutrino spectrum is calculated, which at the moment can only be obtained with the summation method and may be relevant for short baseline reactor experiments using highly enriched uranium fuel. PMID:27081973

  12. Effects of Fission Yield Data in the Calculation of Antineutrino Spectra for 235U (n ,fission) at Thermal and Fast Neutron Energies

    Science.gov (United States)

    Sonzogni, A. A.; McCutchan, E. A.; Johnson, T. D.; Dimitriou, P.

    2016-04-01

    Fission yields form an integral part of the prediction of antineutrino spectra generated by nuclear reactors, but little attention has been paid to the quality and reliability of the data used in current calculations. Following a critical review of the thermal and fast ENDF/B-VII.1 235U 235 fission yields, deficiencies are identified and improved yields are obtained, based on corrections of erroneous yields, consistency between decay and fission yield data, and updated isomeric ratios. These corrected yields are used to calculate antineutrino spectra using the summation method. An anomalous value for the thermal fission yield of 86Ge generates an excess of antineutrinos at 5-7 MeV, a feature which is no longer present when the corrected yields are used. Thermal spectra calculated with two distinct fission yield libraries (corrected ENDF/B and JEFF) differ by up to 6% in the 0-7 MeV energy window, allowing for a basic estimate of the uncertainty involved in the fission yield component of summation calculations. Finally, the fast neutron antineutrino spectrum is calculated, which at the moment can only be obtained with the summation method and may be relevant for short baseline reactor experiments using highly enriched uranium fuel.

  13. Effects of Fission Yield Data in the Calculation of Antineutrino Spectra for ^{235}U(n,fission) at Thermal and Fast Neutron Energies.

    Science.gov (United States)

    Sonzogni, A A; McCutchan, E A; Johnson, T D; Dimitriou, P

    2016-04-01

    Fission yields form an integral part of the prediction of antineutrino spectra generated by nuclear reactors, but little attention has been paid to the quality and reliability of the data used in current calculations. Following a critical review of the thermal and fast ENDF/B-VII.1 ^{235}U fission yields, deficiencies are identified and improved yields are obtained, based on corrections of erroneous yields, consistency between decay and fission yield data, and updated isomeric ratios. These corrected yields are used to calculate antineutrino spectra using the summation method. An anomalous value for the thermal fission yield of ^{86}Ge generates an excess of antineutrinos at 5-7 MeV, a feature which is no longer present when the corrected yields are used. Thermal spectra calculated with two distinct fission yield libraries (corrected ENDF/B and JEFF) differ by up to 6% in the 0-7 MeV energy window, allowing for a basic estimate of the uncertainty involved in the fission yield component of summation calculations. Finally, the fast neutron antineutrino spectrum is calculated, which at the moment can only be obtained with the summation method and may be relevant for short baseline reactor experiments using highly enriched uranium fuel.

  14. Measurement of the mixing leptonic parameter θ13 at the Double Chooz reactor antineutrino experiment

    International Nuclear Information System (INIS)

    The Double Chooz experiment aims at measuring the neutrino mixing parameter θ13 by studying the oscillations of de ν-bare produced by the Chooz nuclear reactors located in France. The experimental concept consists in comparing the signal of two identical 10.3 m3 detectors, allowing to cancel most of the experimental systematic uncertainties. The near detector, whose goal is the flux normalization and a measurement without oscillation, is expected to be delivered in 2013. The farthest detector from the source is taking data since April 2011 and is sensitive to θ13, which is expected to affect both the rate and the shape of the measured de ν-bare. In this thesis, are first presented the Double Chooz experiment, with its ν-bare source, its detection method, and the expected signal and backgrounds. In order to perform a selection, important quantities have to be reconstructed, calibrated, and saved in data files. The channel time offsets determination, the energy and vertex reconstruction algorithm CocoReco, the reconstruction packages of the Common Trunk, and the light trees maker Cheetah are especially presented. Concerning the data analysis, all the selection cuts and results for signal and backgrounds are discussed, particularly the multiplicity cut, the multiple off time window method, the lithium veto cut, and the cosmogenic 9Li background studies. The Double Chooz experiment observed 8,249 de -bare candidates in 227.93 days in its far detector only. The reactor antineutrino flux prediction used the Bugey 4 flux measurement after correction for differences in core composition. The expectation in case of no-oscillation is 8,937 events and this deficit is interpreted as evidence for ν-bare disappearance. From a rate and shape analysis, is found sin22θ = 0,109± 0,030 (stat) ± 0,025 (syst), with Δm231 = 2,32 x 10-3 eV2, while the no-oscillation hypothesis is even excluded at 2.9 σ. (author)

  15. Anti-Neutrino Charged Current Quasi-Elastic Scattering in MINER$\

    Energy Technology Data Exchange (ETDEWEB)

    Chvojka, Jesse John [Univ. of Rochester, NY (United States)

    2012-01-01

    in neutrino interactions. We present the first cross-section measurement for MINER A, the differential cross-section dσ/dQ2 for muon anti-neutrino CCQE scattering on polystyrene scintillator (CH) as well as comparisons to several final state models.

  16. Neutrino-induced reactions on nuclei

    Science.gov (United States)

    Gallmeister, K.; Mosel, U.; Weil, J.

    2016-09-01

    Background: Long-baseline experiments such as the planned deep underground neutrino experiment (DUNE) require theoretical descriptions of the complete event in a neutrino-nucleus reaction. Since nuclear targets are used this requires a good understanding of neutrino-nucleus interactions. Purpose: Develop a consistent theory and code framework for the description of lepton-nucleus interactions that can be used to describe not only inclusive cross sections, but also the complete final state of the reaction. Methods: The Giessen-Boltzmann-Uehling-Uhlenbeck (GiBUU) implementation of quantum-kinetic transport theory is used, with improvements in its treatment of the nuclear ground state and of 2p2h interactions. For the latter an empirical structure function from electron scattering data is used as a basis. Results: Results for electron-induced inclusive cross sections are given as a necessary check for the overall quality of this approach. The calculated neutrino-induced inclusive double-differential cross sections show good agreement data from neutrino and antineutrino reactions for different neutrino flavors at MiniBooNE and T2K. Inclusive double-differential cross sections for MicroBooNE, NOvA, MINERvA, and LBNF/DUNE are given. Conclusions: Based on the GiBUU model of lepton-nucleus interactions a good theoretical description of inclusive electron-, neutrino-, and antineutrino-nucleus data over a wide range of energies, different neutrino flavors, and different experiments is now possible. Since no tuning is involved this theory and code should be reliable also for new energy regimes and target masses.

  17. Study of the elementary (K-, n) reactions to search for the K ¯NN bound state via the 3He (K-, n) reaction at J-PARC

    Science.gov (United States)

    Yamaga, Takumi; Ajimura, S.; Beer, G.; Berucci, C.; Bhang, H.; Bragadireanu, M.; Buehler, P.; Busso, L.; Cargnelli, M.; Choi, S.; Curceanu, C.; Enomoto, S.; Faso, D.; Fujioka, H.; Fujiwara, Y.; Fukuda, T.; Guaraldo, C.; Hashimoto, T.; Hayano, R. S.; Hiraiwa, T.; Iio, M.; Iliescu, M.; Inoue, K.; Ishiguro, Y.; Ishikawa, T.; Ishimoto, S.; Ishiwatari, T.; Itahashi, K.; Iwai, M.; Iwasaki, M.; Kanno, K.; Kato, K.; Kato, Y.; Kawasaki, S.; Kienle, P.; Kim, T.; Kou, H.; Ma, Y.; Marton, J.; Matsuda, Y.; Mizoi, Y.; Morra, O.; Nagae, T.; Noumi, H.; Ohnishi, H.; Okada, S.; Outa, H.; Piscicchia, K.; Vidal, A. Romero; Sada, Y.; Sakaguchi, A.; Sakuma, F.; Sato, M.; Scordo, A.; Sekimoto, M.; Shi, H.; Shirotori, K.; Sirghi, D.; Sirghi, F.; Suzuki, K.; Suzuki, S.; Suzuki, T.; Tanida, K.; Tatsuno, H.; Tokuda, M.; Tomono, D.; Toyoda, A.; Tsukada, K.; Doce, O. Vazquez; Widmann, E.; Wuenschek, B. K.; Yamazaki, T.; Yim, H.; Zhang, Q.; Zmeskal, J.

    2016-05-01

    We have searched for the simplest kaonic nuclear state, K ¯NN, using the in-flight 3He (K-, n) reaction at the J-PARC hadron experimental facility. In the semi-inclusive neutron missing-mass spectrum at θnla b=0° , an excess of yield was observed just below the K- pp mass-threshold, which cannot be explained by any elementary reactions [PTEP 2015, 061D01]. To understand the missing-mass spectrum of 3He (K-, n) X, we investigated the elementary (K-, n) reactions using hydrogen and deuterium targets. The p (K-, n) X missing-mass spectrum was well described by the charge-exchange reaction. However, in the d (K-, n) X spectrum, we observed an excess of yield just below the K- p mass-threshold, which was similar to that in the 3He (K-, n) X spectrum.

  18. Neutrinos from SN 1987A - Implications for cooling of the nascent neutron star and the mass of the electron antineutrino

    Science.gov (United States)

    Loredo, Thomas J.; Lamb, Don Q.

    1989-01-01

    Data on neutrinos from SN 1987A are compared here with parameterized models of the neutrino emission using a consistent and straightforward statistical methodology. The empirically measured detector background spectra are included in the analysis, and the data are compared with a much wider variety of neutrino emission models than was explored previously. It is shown that the inferred neutrino emission model parameters are strongly correlated. The analysis confirms that simple models of the neutrino cooling of the nascent neutron star formed by the SN adequately explain the data. The inferred radius and binding energy of the neutron star are in excellent agreement with model calculations based on a wide range of equations of state. The results also raise the upper limit of the electron antineutrino rest mass to roughly 25 eV at the 95 percent confidence level, roughly 1.5-5 times higher than found previously.

  19. Anharmonicity of internal atomic oscillation and effective antineutrino mass evaluation from gaseous molecular tritium β-decay

    Science.gov (United States)

    Lokhov, Alexey V.; Titov, Nikita A.

    2016-07-01

    Data analysis of the next-generation effective antineutrino mass measurement experiment KATRIN requires reliable knowledge of systematic corrections. In particular, the width of the daughter molecular ion excitation spectrum rovibrational band should be known with better than 1% precision. Very precise ab initio quantum calculations exist, and we compare them with the well-known tritium molecule parameters within the framework of a phenomenological model. The rovibrational band width with accuracy of a few percent is interpreted as a result of the zero-point atomic oscillation in the harmonic potential. The Morse interatomic potential is used to investigate the impact of anharmonic atomic oscillations. The calculated corrections cannot account for the difference between the ab initio quantum calculations and the phenomenological model.

  20. Unbound states of 32Cl and the 31S(p,\\gamma)32Cl reaction rate

    CERN Document Server

    Matoš, M; Linhardt, L E; Bardayan, D W; Nesaraja, C D; Clark, J A; Deibel, C M; O'Malley, P D; Parker, P D

    2011-01-01

    The 31S(p,\\gamma)32Cl reaction is expected to provide the dominant break-out path from the SiP cycle in novae and is important for understanding enrichments of sulfur observed in some nova ejecta. We studied the 32S(3He,t)32Cl charge-exchange reaction to determine properties of proton-unbound levels in 32Cl that have previously contributed significant uncertainties to the 31S(p,\\gamma)32Cl reaction rate. Measured triton magnetic rigidities were used to determine excitation energies in 32Cl. Proton-branching ratios were obtained by detecting decay protons from unbound 32Cl states in coincidence with tritons. An improved 31S(p,\\gamma)32Cl reaction rate was calculated including robust statistical and systematic uncertainties.