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Sample records for muon capture rates

  1. Systematic muon capture rates in PQRPA

    SciTech Connect

    Samana, A. R.; Sande, D.; Krmpotić, F.

    2015-05-15

    In this work we performed a systematic study of the inclusive muon capture rates for several nuclei with A < 60 using the Projected Random Quasi-particle Phase Approximation (PQRPA) as nuclear model, because it is the only RPA model that treats the Pauli Principle correctly. We reckon that the comparison between theory and data for the inclusive muon capture is not a fully satisfactory test on the nuclear model that is used. The exclusive muon transitions are more robust for such a purpose.

  2. Calculation of doublet capture rate for muon capture in deuterium within chiral effective field theory

    NASA Astrophysics Data System (ADS)

    Adam, J.; Tater, M.; Truhlík, E.; Epelbaum, E.; Machleidt, R.; Ricci, P.

    2012-03-01

    The doublet capture rate Λ1 / 2 of the negative muon capture in deuterium is calculated employing the nuclear wave functions generated from accurate nucleon-nucleon (NN) potentials constructed at next-to-next-to-next-to-leading order of heavy-baryon chiral perturbation theory and the weak meson exchange current operator derived within the same formalism. All but one of the low-energy constants that enter the calculation were fixed from pion-nucleon and nucleon-nucleon scattering data. The low-energy constant dˆR (cD), which cannot be determined from the purely two-nucleon data, was extracted recently from the triton β-decay and the binding energies of the three-nucleon systems. The calculated values of Λ1 / 2 show a rather large spread for the used values of the dˆR. Precise measurement of Λ1 / 2 in the future will not only help to constrain the value of dˆR, but also provide a highly nontrivial test of the nuclear chiral EFT framework. Besides, the precise knowledge of the constant dˆR will allow for consistent calculations of other two-nucleon weak processes, such as proton-proton fusion and solar neutrino scattering on deuterons, which are important for astrophysics.

  3. Muon capture in deuterium

    NASA Astrophysics Data System (ADS)

    Ricci, P.; Truhlík, E.; Mosconi, B.; Smejkal, J.

    2010-06-01

    Model dependence of the capture rates of the negative muon capture in deuterium is studied starting from potential models and the weak two-body meson exchange currents constructed in the tree approximation and also from an effective field theory. The tree one-boson exchange currents are derived from the hard pion chiral Lagrangians of the NΔπρωa system. If constructed in conjunction with the one-boson exchange potentials, the capture rates can be calculated consistently. On the other hand, the effective field theory currents, constructed within the heavy baryon chiral perturbation theory, contain a low energy constant d that cannot be extracted from data at the one-particle level nor determined from the first principles. Comparative analysis of the results for the doublet transition rate allows us to extract the constant d.

  4. First measurements of muon production rate using a novel pion capture system at MuSIC

    NASA Astrophysics Data System (ADS)

    Cook, S.; D'Arcy, R.; Fukuda, M.; Hatanaka, K.; Hino, Y.; Kuno, Y.; Lancaster, M.; Mori, Y.; Nam, T. H.; Ogitsu, T.; Sakamoto, H.; Sato, A.; Truong, N. M.; Yamamoto, A.; Yoshida, M.; Wing, M.

    2013-02-01

    The MuSIC (Muon Science Innovative Channel) beam line at RCNP (Research Centre for Nuclear Physics), Osaka will be the most intense source of muons in the world. A proton beam is incident on a target and, by using a novel capture solenoid, guides the produced pions into the beam line where they subsequently decay to muons. This increased muon flux will allow more precise measurements of cLFV (charged Lepton Flavour Violation) as well as making muon beams more economically feasible. Currently the first 36° of solenoid beam pipe have been completed and installed for testing with low proton current of 1 nA. Measurements of the total particle flux and the muon life time were made. The measurements were taken using thin plastic scintillators coupled to MPPCs (Multi-Pixel Photon Counter) that surrounded a magnesium or copper stopping target. The scintillators were used to record which particles stopped and their subsequent decay times giving a muon yield of 8.5 × 105 muons W-1proton beam or 3 × 108 muons s-1 when using the RCNP's full power (400 W).

  5. The MuCap experiment: A measurement of the muon capture rate in hydrogen gas

    SciTech Connect

    Banks, T. I.

    2007-10-26

    We have recently measured the rate of nuclear muon capture by the proton, using a novel technique which involves a time projection chamber operating in ultraclean, deuterium-depleted hydrogen gas. The target's low gas density of 1% compared to liquid hydrogen is key to avoiding uncertainties that arise from the formation of muonic molecules. The capture rate from the hyperfine singlet ground state of the {mu}p atom was obtained from the difference between the {mu}{sup -} disappearance rate in hydrogen and the world average for the {mu}{sup +} decay rate, yielding {lambda}{sub S} = 725.0{+-}17.4 s{sup -1}, from which the induced pseudoscalar coupling of the nucleon, g{sub P}(q{sup 2} = 0.88m{sub {mu}}{sup 2}) = 7.3{+-}1.1, is extracted. This result is consistent with theoretical predictions for g{sub P} that are based on the approximate chiral symmetry of QCD.

  6. Muon Capture on ^3H

    NASA Astrophysics Data System (ADS)

    Golak, Jacek; Skibiński, Roman; Witała, Henryk; Topolnicki, Kacper; Kamada, Hiroyuki; Nogga, Andreas; Marcucci, Laura E.

    2017-01-01

    The μ ^- + ^3H → ν _μ + n + n + n capture reaction is studied under full inclusion of final-state interactions with the AV18 nucleon-nucleon potential and the Urbana IX three-nucleon force. We employ the single nucleon weak current operator comprising the dominant relativistic corrections to obtain first estimates of the total capture rates based on realistic forces. Our results are compared with older theoretical predictions.

  7. A Measurement of the Rate of Muon Capture in Hydrogen Gas andDetermination of the Proton's Induced Pseudoscalar Coupling gP

    SciTech Connect

    Banks, Thomas Ira

    2007-07-01

    This dissertation describes a measurement of the rate ofnuclear muon capture by the proton, performed by the MuCap Collaborationusing a new technique based on a time projection chamber operating inultraclean, deuterium-depleted hydrogen gas at room temperature and 1 MPapressure. The hydrogen target's low gas density of 1 percent compared toliquid hydrogen is key to avoiding uncertainties that arise from theformation of muonic molecules. The capture rate was obtained from thedifference between the μ- disappearance rate in hydrogen--as determinedfrom data collected in the experiment's first physics run in fall2004--and the world averagefor the μ+ decay rate. After combining theresults of my analysis with the results from another independent analysisof the 2004 data, the muon capture rate from the hyperfine singlet groundstate of the mu-p atom is found to be ΛS = 725.0 ± 17.4 1/s, fromwhich the induced pseudoscalar coupling of the nucleon, gP(q2 = -0.88m$2\\atop{μ}$)= 7.3 ± 1.1, is extracted. This result for gP is consistent withtheoretical predictions that are based on the approximate chiral symmetryof QCD.

  8. Muon capture on deuteron and He3

    NASA Astrophysics Data System (ADS)

    Marcucci, L. E.; Piarulli, M.; Viviani, M.; Girlanda, L.; Kievsky, A.; Rosati, S.; Schiavilla, R.

    2011-01-01

    The muon-capture reactions H2(μ-,νμ)nn and He3(μ-,νμ)H3 are studied with conventional or chiral realistic potentials and consistent weak currents. The initial and final A=2 and A=3 nuclear wave functions are obtained from the Argonne v18 or chiral next-to-next-to-next-to leading order (N3LO) two-nucleon potential, in combination with, respectively, the Urbana IX or chiral next-to-next-to leading order (N2LO) three-nucleon potential in the case of A=3. The weak current consists of polar- and axial-vector components. The former are related to the isovector piece of the electromagnetic current via the conserved-vector-current hypothesis. These and the axial currents are derived either in a meson-exchange or in a chiral effective field theory (χEFT) framework. There is one parameter (either the N-to-Δ axial coupling constant in the meson-exchange model, or the strength of a contact term in the χEFT model) that is fixed by reproducing the Gamow-Teller matrix element in tritium β decay. The model dependence relative to the adopted interactions and currents (and cutoff sensitivity in the χEFT currents) is weak, resulting in total rates of 392.0±2.3 s-1 for A=2, and 1484±13 s-1 for A=3, where the spread accounts for this model dependence.

  9. Radiative muon capture in hydrogen and nucleon excitation

    SciTech Connect

    Beder, D. S.; Fearing, H. W.

    1989-06-01

    We extend our previous calculations of radiative muon capture on a nucleonand present detailed calculations of the role of the ..delta..(1232) using animproved ..delta..-nucleon-..gamma.. vertex and for a variety of values of theinduced pseudoscalar coupling /ital g//sub /ital P//. We also present calculations ofthe photon-muon spin asymmetry and examine effects of the ..delta..(1232)there.

  10. The stopping rate of negative cosmic-ray muons near sea level

    NASA Technical Reports Server (NTRS)

    Spannagel, G.; Fireman, E. L.

    1971-01-01

    A production rate of 0.065 + or - 0.003 Ar-37 atom/kg min of K-39 at 2-mwe depth below sea level was measured by sweeping argon from potassium solutions. This rate is unaffected by surrounding the solution by paraffin and is attributed to negative muon captures and the electromagnetic interaction of fast muons, and not to nucleonic cosmic ray component. The Ar-37 yield from K-39 by the stopping of negative muons in a muon beam of a synchrocyclotron was measured to be 8.5 + or - 1.7%. The stopping rate of negative cosmic ray muons at 2-mwe depth below sea level from these measurements and an estimated 17% electromagnetic production is 0.63 + or - 0.13 muon(-)/kg min. Previous measurements on the muon stopping rate vary by a factor of 5. Our value is slightly higher but is consistent with two previous high values. The sensitivity of the Ar-37 radiochemical method for the detection of muons is considerably higher than that of the previous radiochemical methods and could be used to measure the negative muon capture rates at greater depths.

  11. Measurement of muon capture on the proton to 1% precision and determination of the pseudoscalar coupling gP.

    PubMed

    Andreev, V A; Banks, T I; Carey, R M; Case, T A; Clayton, S M; Crowe, K M; Deutsch, J; Egger, J; Freedman, S J; Ganzha, V A; Gorringe, T; Gray, F E; Hertzog, D W; Hildebrandt, M; Kammel, P; Kiburg, B; Knaack, S; Kravtsov, P A; Krivshich, A G; Lauss, B; Lynch, K R; Maev, E M; Maev, O E; Mulhauser, F; Petitjean, C; Petrov, G E; Prieels, R; Schapkin, G N; Semenchuk, G G; Soroka, M A; Tishchenko, V; Vasilyev, A A; Vorobyov, A A; Vznuzdaev, M E; Winter, P

    2013-01-04

    The MuCap experiment at the Paul Scherrer Institute has measured the rate Λ(S) of muon capture from the singlet state of the muonic hydrogen atom to a precision of 1%. A muon beam was stopped in a time projection chamber filled with 10-bar, ultrapure hydrogen gas. Cylindrical wire chambers and a segmented scintillator barrel detected electrons from muon decay. Λ(S) is determined from the difference between the μ(-) disappearance rate in hydrogen and the free muon decay rate. The result is based on the analysis of 1.2 × 10(10) μ(-) decays, from which we extract the capture rate Λ(S) = (714.9 ± 5.4(stat) ± 5.1(syst)) s(-1) and derive the proton's pseudoscalar coupling g(P)(q(0)(2) = -0.88 m(μ)(2)) = 8.06 ± 0.55.

  12. Comparison of Muon Capture in Light and in Heavy Nuclei

    SciTech Connect

    Measday, David F.; Stocki, Trevor J.

    2007-10-26

    We have recently completed an experimental study at TRIUMF of muon capture in the following elements, N, Al, Si, Ca, Fe, Ni, I, Au, and Bi. We detected the nuclear gamma rays emitted by the product nuclei after muon capture. The energy of the gamma ray identifies the source nuclide, and thus the reaction which has occurred. Our data are of better quality, and more comprehensive than any other data set in the literature. The ({mu}{sup -},{nu}n) reaction is always dominant. In light nuclei, reactions such as ({mu}{sup -},{nu}p) and ({mu}{sup -},{nu}pn) can occur, but not for heavy nuclei. However the reverse is true for reactions such as ({mu}{sup -},{nu}3n) and ({mu}{sup -},{nu}4n), which are very rare in light nuclei, but easily detected in heavy elements. We shall discuss how such information can be useful in calculations of neutrino-nucleus interactions, and of electron-capture in supernovae.

  13. Muon capture on deuteron and 3He

    SciTech Connect

    Marcucci, L. E.; Piarulli, M.; Viviani, M.; Girlanda, L.; Kievsky, A.; Rosati, S.; Schiavilla, R.

    2011-01-01

    The muon capture reactions 2H(μ-, vμ)nn and 3He(μ-, vμ)3H are studied with realistic or chiral potentials and consistent weak currents. The initial and final A = 2 and 3 nuclear wave functions are obtained from the Argonne v18 (AV18) or chiral N3LO (N3LO) two-nucleon potential, in combination with, respectively, the Urbana IX (UIX) or chiral N2LO (N2LO) three-nucleon potential in the case of A = 3. The weak current consists of polar- and axial-vector components. The former are related to the isovector piece of the electromagnetic current via the conserved-vector-current hypothesis. These and the axial currents are derived either in a meson-exchange or in a chiral effective field theory ( EFT) framework. There is one parameter (either the N-to-Delta axial coupling constant in the meson-exchange model, or the strength of a contact term in the EFT model) which is fixed by reproducing the Gamow-Teller matrix element in tritium-decay. The model dependence relative to the adopted interactions and currents (and cutoff sensitivity in the EFT currents) is weak, resulting in total rates of 392.0 ± 2.3 s-1 for A = 2, and 1484 ± 13 s-1 for A = 3, where the spread accounts for this model dependence.

  14. Chiral effective field theory predictions for muon capture on deuteron and {3}He.

    PubMed

    Marcucci, L E; Kievsky, A; Rosati, S; Schiavilla, R; Viviani, M

    2012-02-03

    The muon-capture reactions {2}H(μ{-},ν{μ})nn and {3}He(μ{-},ν{μ}){3}H are studied with nuclear potentials and charge-changing weak currents, derived in chiral effective field theory. The low-energy constants (LECs) c{D} and c{E}, present in the three-nucleon potential and (c{D}) axial-vector current, are constrained to reproduce the A=3 binding energies and the triton Gamow-Teller matrix element. The muon-capture rates on deuteron and {3}He are predicted to be 399±3  sec{-1} and 1494±21  sec{-1}, respectively. The spread accounts for the cutoff sensitivity, as well as uncertainties in the LECs and electroweak radiative corrections. By comparing the calculated and precisely measured rates on {3}He, a value for the induced pseudoscalar form factor is obtained in good agreement with the chiral perturbation theory prediction.

  15. Meson exchange currents for nuclear muon capture by {sup 3}He

    SciTech Connect

    Congleton, J.G.; Truhlik, E.

    1995-05-10

    We have calculated exchange corrections for nuclear muon capture by {sup 3}He using the hard pion method for the currents and wavefunctions for {sup 3}He and {sup 3}H found by the coupled rearrangement channel method. The result for the rate (triton asymmetry) has an uncertainty of 3% (1%) due mainly to the uncertainty in the value of {ital f}{sub {pi}{ital N}{Delta}} (various factors). {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  16. Radiative muon capture on carbon, oxygen, and calcium

    SciTech Connect

    Armstrong, D.S.; Ahmad, S.; Burnham, R.A.; Gorringe, T.P.; Hasinoff, M.D.; Larabee, A.J.; Waltham, C.E. ); Azuelos, G.; Macdonald, J.A.; Numao, T.; Poutissou, J. ); Blecher, M.; Wright, D.H. ); Clifford, E.T.H.; Summhammer, J. University of Victoria, Victoria, British Columbia ); Depommier, P.; Poutissou, R. ); Mes, H. ); Robertson, B.C. )

    1991-03-01

    The photon energy spectra from radiative muon capture on {sup 12}C, {sup 16}O, and {sup 40}Ca have been measured using a time projection chamber as a pair spectrometer. The branching ratio for radiative muon capture is sensitive to {ital g}{sub {ital p}}, the induced pseudoscalar coupling constant of the weak interaction. Expressed in terms of the axial-vector weak coupling constant {ital g}{sub {ital a}}, values of {ital g}{sub {ital p}}/{ital g}{sub {ital a}}=5.7{plus minus}0.8 and {ital g}{sub {ital p}}/{ital g}{sub {ital a}}=7.3{plus minus}0.9 are obtained for {sup 40}Ca and {sup 16}O, respectively, from comparison with phenomenological calculations of the nuclear response. From comparison with microscopic calculations, values of {ital g}{sub {ital p}}/{ital g}{sub {ital a}}=4.6{plus minus}1.8, 13.6{sub {minus}1.9}{sup +1.6}, and 16.2{sub {minus}0.7}{sup +1.3} for {sup 40}Ca, {sup 16}O, and {sup 12}C, respectively, are obtained. The microscopic results are suggestive of a renormalization of the nucleonic form factors within the nucleus.

  17. Muon capture in a general class of weak models

    NASA Astrophysics Data System (ADS)

    Botella, F. J.

    1985-10-01

    We study muon capture by 12C in a general class of weak models. There is always a parameter characteristic of the weak model that can be extracted in a nuclear-model-independent way from the average polarization Pav, the longitudinal polarization PNL and the asymmetry α in the angular distribution of recoils. For a less general class of models the asymmetry α is unnecessary. Using the experimental values of PNL and Pav we get a lower bound for the mass of the right-handed gauge boson of the left-right-symmetric model, MWR>=2.5MWL, in a nuclear-model-independent way. The dependence of this bound on the experimental values is also discussed.

  18. Muon capture on the deuteron and the neutron-neutron scattering length

    NASA Astrophysics Data System (ADS)

    Marcucci, L. E.; Machleidt, R.

    2014-11-01

    Background: We consider the muon capture reaction μ-+2H→νμ+n +n , which presents a "clean" two-neutron (n n ) system in the final state. We study here its capture rate in the doublet hyperfine initial state (ΓD). The total capture rate for the muon capture μ-+3He→νμ+3H (Γ0) is also analyzed, although, in this case, the n n system is not so clean anymore. Purpose: We investigate whether ΓD (and Γ0) could be sensitive to the n n S -wave scattering length (an n), and we check on the possibility to extract an n from an accurate measurement of ΓD. Method: The muon capture reactions are studied with nuclear potentials and charge-changing weak currents, derived within chiral effective field theory. The next-to-next-to-next-to-leading-order chiral potential with cutoff parameter Λ =500 MeV is used, but the low-energy constant (LEC) determining an n is varied so as to obtain an n=-18.95 ,-16.0 ,-22.0 , and +18.22 fm. The first value is the present empirical one, while the last one is chosen such as to lead to a di-neutron bound system with a binding energy of 139 keV. The LEC's cD and cE, present in the three-nucleon potential and axial-vector current (cD), are constrained to reproduce the A =3 binding energies and the triton Gamow-Teller matrix element. Results: The capture rate ΓD is found to be 399 (3 ) s-1 for an n=-18.95 and -16.0 fm; and 400 (3 ) s-1 for an n=-22.0 fm. However, in the case of an n=+18.22 fm, the result of 275 (3 ) s-1 [ 135 (3 ) s-1 ] is obtained, when the di-neutron system in the final state is unbound (bound). The total capture rate Γ0 for muon capture on 3He is found to be 1494(15), 1491(16), 1488(18), and 1475(16) s-1 for an n=-18.95 ,-16.0 ,-22.0 , and +18.22 fm, respectively. All the theoretical uncertainties are due to the fitting procedure and radiative corrections. Conclusions: Our results seem to exclude the possibility of constraining a negative an n with an uncertainty of less than ˜±3 fm through an accurate

  19. Feasibility of Sea-level Cosmic-Ray Muon-Capture SNM Detection

    SciTech Connect

    Rosenberg, L; Bernstein, A

    2005-03-11

    The first part of this report argues the average time between signal events for X-rays from negative muon capture on SNM is from a few to a few 10's of minutes, depending on how sophisticated one care's to make the detector. The second part of this report argues that the recoil proton background in the energy resolution window can be orders of magnitude larger than the expected signal. How could one evade this result? Firstly, one could conceive of a very highly segmented muon counter (or electromagnetic calorimeter) system to actually detect a stopping muon. This would be extraordinarily expensive for a large area and volume of a cargo container. There are also quite a few assumptions we applied to make the calculations tractable. For instance, we assumed the detector was fully efficient for a neutron recoil. probably something like 25% or 50% is more appropriate. However, probably the biggest uncertainty is the neutron energy spectrum. The Boehm et al. paper discusses the range of spectrum parameterizations, some of which are considerably softer and will lower the high-energy proton yield. This outcome is certainly possible. However, given the difference between signal and background rates, it would take a considerable change in detector parameters and particle yields to change the basic conclusion that this technique does not appear promising.

  20. Chiral effective field theory predictions for muon capture on deuteron and $^3$He

    SciTech Connect

    Laura E. Marcucci, A. Kievsky, S. Rosati, R. Schiavilla, M. Viviani

    2012-01-01

    The muon-capture reactions {sup 2}H({mu}{sup -}, {nu}{sub {mu}})nn and {sup 3}He({mu}{sup -},{nu}{sub {mu}}){sup 3}H are studied with nuclear strong-interaction potentials and charge-changing weak currents, derived in chiral effective field theory. The low-energy constants (LEC's) c{sub D} and c{sub E}, present in the three-nucleon potential and (c{sub D}) axial-vector current, are constrained to reproduce the A=3 binding energies and the triton Gamow-Teller matrix element. The vector weak current is related to the isovector component of the electromagnetic current via the conserved-vector-current constraint, and the two LEC's entering the contact terms in the latter are constrained to reproduce the A=3 magnetic moments. The muon capture rates on deuteron and {sup 3}He are predicted to be 399 {+-} 3 sec{sup -1} and 1494 {+-} 21 sec{sup -1}, respectively, where the spread accounts for the cutoff sensitivity as well as uncertainties in the LEC's and electroweak radiative corrections. By comparing the calculated and precisely measured rates on {sup 3}He, a value for the induced pseudoscalar form factor is obtained in good agreement with the chiral perturbation theory prediction.

  1. Equivalent dose rate by muons to the human body.

    PubMed

    Băcioiu, I

    2011-11-01

    In this paper, the relative sensitivity from different human tissues of the human body, at a ground level, from muon cosmic radiation has been studied. The aim of this paper was to provide information on the equivalent dose rates received from atmospheric muons to human body, at the ground level. The calculated value of the effective dose rate by atmospheric muons plus the radiation levels of the natural annual background radiation dose, at the ground level, in the momentum interval of cosmic ray muon (0.2-120.0 GeV/c) is about 2.106±0.001 mSv/y, which is insignificant in comparison with the values of the doses from the top of the atmosphere.

  2. Neutron emission following muon capture in Ce-142, Ce-140, Ba-138, and Sn-120.

    NASA Technical Reports Server (NTRS)

    Lucas, G. R., Jr.; Martin, P.; Welsh, R. E.; Jenkins, D. A.; Powers, R. J.; Kunselman, A. R.; Miller, G. H.

    1973-01-01

    Branching ratios to excited nuclear states formed after muon capture have been measured with Ge(Li) detectors. The delayed gamma rays were observed in studies of muonic Ce-142, Ce-140, Ba-138, and Sn-120, using separated isotopes. The resulting isotopes formed indicate at least a 60% probability of neutron emission upon muon capture, with the most likely product resulting from single-neutron emission. No evidence for delayed proton emission with a probability higher than 2% was found. Using our more precise energies for the observed nuclear transitions, we present revised energy levels schemes for La-141, La-139, Cs-137, and In-119.

  3. Feasibility study of nuclear transmutation by negative muon capture reaction using the PHITS code

    NASA Astrophysics Data System (ADS)

    Abe, Shin-ichiro; Sato, Tatsuhiko

    2016-06-01

    Feasibility of nuclear transmutation of fission products in high-level radioactive waste by negative muon capture reaction is investigated using the Particle and Heave Ion Transport code System (PHITS). It is found that about 80 % of stopped negative muons contribute to transmute target nuclide into stable or short-lived nuclide in the case of 135Cs, which is one of the most important nuclide in the transmutation. The simulation result also indicates that the position of transmutation is controllable by changing the energy of incident negative muon. Based on our simulation, it takes approximately 8.5 × 108years to transmute 500 g of 135Cs by negative muon beam with the highest intensity currently available.

  4. A cylindrical drift chamber for radiative muon capture experiments at TRIUMF

    SciTech Connect

    Henderson, R.S.; Dawson, R.J.; Azuelos, G.; Robertson, B.C. ); Hasinoff, M.D.; Ahamad, S.; Gorringe, T.P. ); Serna-Angel, A.; Blecher, M.; Wright, D.H. )

    1990-06-01

    In the Standard Model, the weak interaction is purely V-A in character. However in semileptonic reactions the strong force induces additional couplings. Radiative muon capture (RMC), {mu}{sup {minus}}{ital Z} {r arrow} {nu}({ital Z}{minus}1){gamma}, is a process which is particularly sensitive to the induced pseudoscalar coupling constant, {ital g{sub p}}, which is still very poorly determined experimentally. Due to the extremely small branching ratio ({approximately} 6 {times} 10{sup {minus}8}), the elementary reaction {mu}{sup {minus}}{ital p} {r arrow} {nu}{ital n}{gamma} has never been measured. Effort to date has concentrated on nuclear RMC where the branching ratio is much larger, but the interpretation of these results is hindered by nuclear structure uncertainties. A measurement is being carried out at TRIUMF to determine the rate of RMC on hydrogen to a precision of 8% leading to a determination of {ital g{sub p}} with an error of 10%. The detection system is based on a large volume cylindrical drift chamber, in an axial magnetic field, acting as an e{sup +}e{sup {minus}} pair spectrometer with a solid angle of {approx equal} 2 {pi}. The design, construction and performance of the cylindrical drift chamber are discussed.

  5. Radiative Muon Capture on Hydrogen and the Induced Pseudoscalar Coupling

    SciTech Connect

    Jonkmans, G.; Ahmad, S.; Armstrong, D.; Azuelos, G.; Bertl, W.; Blecher, M.; Chen, C.; Depommier, P.; Doyle, B.; von Egidy, T.; Gorringe, T.; Gumplinger, P.; Hasinoff, M.; Healey, D.; Larabee, A.; Macdonald, J.; McDonald, S.; Munro, M.; Poutissou, J.; Poutissou, R.; Robertson, B.; Sample, D.; Saettler, E.; Sigler, C.; Taylor, G.; Wright, D.; Zhang, N. ||||||||

    1996-11-01

    The first measurement of the elementary process {mu}{sup {minus}}{ital p}{r_arrow}{nu}{sub {mu}}{ital n}{gamma} is reported. A photon pair spectrometer was used to measure the partial branching ratio (2.10{plus_minus}0.22){times}10{sup {minus}8} for photons of {ital k}{gt}60 MeV. The value of the weak pseudoscalar coupling constant determined from the partial branching ratio is {ital g}{sub {ital p}}({ital q}{sup 2}={minus}0.88{ital m}{sub {mu}}{sup 2})=(9.8{plus_minus}0.7{plus_minus}0.3){ital g}{sub {ital a}}(0), where the first error is the quadrature sum of statistical and systematic uncertainties and the second error is due to the uncertainty in {lambda}{sub op}, the decay rate of the ortho to para {ital p}{mu}{ital p} molecule. This value of {ital g}{sub {ital p}} is {approximately}1.5 times the prediction of partial conservation of axial current and pion-pole dominance. {copyright} {ital 1996 The American Physical Society.}

  6. Seasonal variations of the rate of multiple-muons in the Gran Sasso underground laboratory

    NASA Astrophysics Data System (ADS)

    Ronga, F.

    2017-03-01

    It is well known that the rate of cosmic ray muons depends on the atmospheric temperature, and that for events with a single muon the peak of the rate is in summer, in underground laboratories in the northern hemisphere. In 2015 the MINOS experiment, in USA, found that, for small distances between the multiple-muons, the rate of multiple-muons peaks in the winter and that the amplitude of the modulation is smaller than in the case of a single muon. I have done a re-analysis of data of the past MACRO experiment. The result is that under Gran Sasso the rate of multiple-muons at small distances peaks in the summer. This difference with MINOS could be explained by differences in the atmospheric temperature due to latitude. This results could be of interest for dark matter experiments looking to dark matter seasonal modulation due to the Earth's motion.

  7. Delivering the world's most intense muon beam

    NASA Astrophysics Data System (ADS)

    Cook, S.; D'Arcy, R.; Edmonds, A.; Fukuda, M.; Hatanaka, K.; Hino, Y.; Kuno, Y.; Lancaster, M.; Mori, Y.; Ogitsu, T.; Sakamoto, H.; Sato, A.; Tran, N. H.; Truong, N. M.; Wing, M.; Yamamoto, A.; Yoshida, M.

    2017-03-01

    A new muon beam line, the muon science innovative channel, was set up at the Research Center for Nuclear Physics, Osaka University, in Osaka, Japan, using the 392 MeV proton beam impinging on a target. The production of an intense muon beam relies on the efficient capture of pions, which subsequently decay to muons, using a novel superconducting solenoid magnet system. After the pion-capture solenoid, the first 36° of the curved muon transport line was commissioned and the muon flux was measured. In order to detect muons, a target of either copper or magnesium was placed to stop muons at the end of the muon beam line. Two stations of plastic scintillators located upstream and downstream from the muon target were used to reconstruct the decay spectrum of muons. In a complementary method to detect negatively charged muons, the x-ray spectrum yielded by muonic atoms in the target was measured in a germanium detector. Measurements, at a proton beam current of 6 pA, yielded (10.4 ±2.7 )×1 05 muons per watt of proton beam power (μ+ and μ-), far in excess of other facilities. At full beam power (400 W), this implies a rate of muons of (4.2 ±1.1 )×1 08 muons s-1 , among the highest in the world. The number of μ- measured was about a factor of 10 lower, again by far the most efficient muon beam produced. The setup is a prototype for future experiments requiring a high-intensity muon beam, such as a muon collider or neutrino factory, or the search for rare muon decays which would be a signature for phenomena beyond the Standard Model of particle physics. Such a muon beam can also be used in other branches of physics, nuclear and condensed matter, as well as other areas of scientific research.

  8. Mesure du taux de la capture radiative du muon par l'hydrogene liquide

    NASA Astrophysics Data System (ADS)

    Jonkmans, Guy

    À basse énergie, l'interaction faible entre leptons et quarks est décrite par une interaction de la forme courant × courant de type V - A. La présence de l'interaction forte induit des couplages additionnels qui doivent être déterminés expérimentalement. De ceux-ci, le couplage pseudoscalaire induit, gp , est mesuré avec la plus grande incertitude et fait l'objet de la présente recherche. L'hypothèse du Courant Axial Partiellement Conservé (CAPC) et l'usage de la relation de Goldberger-Treiman relie gp au couplage axial ga . Cette relation a été vérifiée traditionnellement par la Capture Ordinaire du Muon (COM) à une valeur fixe du moment de transfert q. La Capture Radiative du Muon (CRM), m- p-->nnmg , est un meilleur outil pour l'étude de gp à cause de sa dépendance variable en q2 qui offre une plus grande sensibilité dans la partie à haute énergie du spectre des photons. Toutefois, le petit rapport d'embranchement (~10-8) de la CRM par rapport à la désintégration du muon a retardé cette mesure jusqu'à ce jour. La théorie et les difficultés expérimentales associées à la détection des photons de CRM sont présentées au deuxième chapitre. On décrit ensuite, au troisième chapitre, les composantes du système de détection. Ce détecteur est un spectromètre à paires de grand angle solide (~3p) et qui permet l'observation des photons par l'analyse des électrons et des positrons de photo-conversion. Ainsi, le bruit de fond important des neutrons de la COM ne constitue pas un problème pour cette mesure. Nous décrivons, au quatrième chapitre, toutes les étapes de l'analyse, nécessaires pour la réduction des multiples bruits de fond. Le cinquième chapitre présente le calcul des efficacités ainsi que l'estimation des erreurs systématiques. Le sixième chapitre démontre comment l'on extrait le rapport d'embranchement pour la CRM ainsi que la valeur ae gp . On insiste sur la dépendance de gp en fonction de la valeur de

  9. Multi-jet production rates in deep-inelastic muon-proton scattering

    SciTech Connect

    Salgado, C.W. )

    1992-02-01

    Measurements of forward multi-jet production rates in deep-inelastic muon-proton scattering are presented. Data were taken with a 490 GeV muon beam incident on a hydrogen target. Jets were defined using the JADE jet finding algorithm. The measured rates are presented as function of W, the hadronic center-of-mass energy and the jet resolution parameter, [ital y][sub [ital cut

  10. Cosmogenic Chlorine-36 Production in Calcite by Muons

    NASA Astrophysics Data System (ADS)

    Stone, J. O. H.; Evans, J. M.; Fifield, L. K.; Allan, G. L.; Cresswell, R. G.

    1998-02-01

    At depths below a few metres, 36Cl production in calcite is initiated almost entirely by cosmic ray muons. The principal reactions are (1) direct negative muon capture by Ca; 40Ca(μ -,α) 36Cl, and (2) capture by 35Cl of secondary neutrons produced in muon capture and muon-induced photodisintegration reactions. We have determined rates for 36Cl and neutron production due to muon capture in calcite from a 20 m (5360 g cm -2) depth profile in limestone. The 36Cl yield from muon capture by Ca in pure calcite is 0.012 ± 0.002 atom per stopped negative muon. The surface production rate of 36Cl by muon capture on Ca in calcite is, therefore, 2.1 ± 0.4 atom g -1a -1 at sea level and high latitude, approximately 11% of the production rate by Ca spallation. If it is assumed that 34% of the negative muons are captured by the Ca atom in calcite, the α-yield from 40Ca following muon capture is 0.043 ± 0.008, somewhat lower than the result of a recent muon irradiation experiment (0.062 ± 0.020), but well within the extremes of existing theoretical predictions (0.0033-0.15). The average neutron yield following muon capture in pure calcite is 0.44 ± 0.15 secondary neutrons per stopped negative muon, in good agreement with existing theoretical predictions. Cosmogenic isotope production by muons must be taken into account when dating young geomorphic surfaces, especially those created by excavation of only a few metres of overlying rock. Attention to isotope production by muons is also crucial to determining surface erosion rates accurately. Due to the deep penetration of muons compared to cosmic ray hadrons, the accumulation of muon-produced 36Cl is less sensitive to erosion than that of spallogenic 36Cl. Although production by muons at the surface is only a small fraction of production by spallation, the fraction of muon-produced 36Cl in rapidly eroding limestone surfaces can approach 50%. In such cases, erosion rates estimated using conventional models which attribute

  11. Measuring radiative capture rates at DRAGON

    NASA Astrophysics Data System (ADS)

    Hager, U.; Davids, B.; Fallis, J.; Greife, U.; Hutcheon, D. A.; Rojas, A.; Ruiz, C.

    2013-04-01

    The DRAGON recoil separator facility is located at the ISAC facility at TRIUMF, Vancouver. It is designed to measure radiative alpha and proton capture reactions of astrophysical importance in inverse kinematics. The Supernanogan ion source at ISAC provides stable beams of high intensities. The DRAGON collaboration has taken advantage of this over the last years by measuring several reactions requiring high-intensity stable oxygen beams. In particular,the ^17O(p,γ) and ^16O(α,γ) reaction rates were recently measured. The former reaction is part of the hot CNO cycle, and strongly influences the abundance of ^18F in classical novae. Because of its relatively long lifetime, ^18F is a possible target for satellite-based gamma-ray spectroscopy. The ^16O(α,γ) reaction plays a role in steady-state helium burning in massive stars, where it follows the ^12C(α,γ) reaction. At astrophysically relevant energies, the reaction proceeds exclusively via direct capture, resulting in a low rate. In both cases, the unique capabilities of DRAGON enabled determination not only of the total reaction rates, but also of decay branching ratios. Results from both experiments will be presented.

  12. Stopping rate of negative cosmic-ray muons near sea level.

    NASA Technical Reports Server (NTRS)

    Spannagel, G.; Fireman, E. L.

    1972-01-01

    A relatively simple method for measuring with high sensitivity the rate of stopped negative muons is described. A process in which Ar-37 is obtained from K-39 in connection with the stopping of a negative muon was used in the experiments. The Ar-37 activity can be measured in small proportional counters with extremely low backgrounds. It is possible to remove Ar-37 from potassium acetate powder at room temperature with almost 100 per cent efficiency merely by trapping the gas from the storage container with a charcoal trap at the liquid nitrogen temperature.

  13. Measurements with a Ge detector and Monte Carlo computations of dose rate yields due to cosmic muons.

    PubMed

    Clouvas, A; Xanthos, S; Antonopoulos-Domis, M; Silva, J

    2003-02-01

    The present work shows how portable Ge detectors can be useful for measurements of the dose rate due to ionizing cosmic radiation. The methodology proposed converts the cosmic radiation induced background in a Ge crystal (energy range above 3 MeV) to the absorbed dose rate due to muons, which are responsible for 75% of the cosmic radiation dose rate at sea level. The key point is to observe in the high energy range (above 20 MeV) the broad muon peak resulting from the most probable energy loss of muons in the Ge detector. An energy shift of the muon peak was observed, as expected, for increasing dimensions of three Ge crystals (10%, 20%, and 70% efficiency). Taking into account the dimensions of the three detectors the location of the three muon peaks was reproduced by Monte Carlo computations using the GEANT code. The absorbed dose rate due to muons has been measured in 50 indoor and outdoor locations at Thessaloniki, the second largest town of Greece, with a portable Ge detector and converted to the absorbed dose rate due to muons in an ICRU sphere representing the human body by using a factor derived from Monte Carlo computations. The outdoor and indoor mean muon dose rate was 25 nGy h(-1) and 17.8 nGy h(-1), respectively. The shielding factor for the 40 indoor measurements ranges from 0.5 to 0.9 with a most probable value between 0.7-0.8.

  14. Toward a QCD analysis of jet rates in deep-inelastic Muon-Proton scattering

    SciTech Connect

    Salgado, C.W.; E665 Collaboration

    1993-08-01

    Measurements of multi-jet production rates in deep-inelastic Muon-Proton scattering at Fermilab-E665 are presented. Jet rates defined by the JADE clustering algorithm are compared to perturbative Quantum chromodynamics (PQCD) and different Monte Carlo model predictions. The applicability of the jet-parton duality hypothesis is studied. We obtain hadronic jet rates which are approximately a factor of two higher than PQCD predictions at the parton level. Possible causes for this discrepancy are discussed.

  15. Calculation on cosmic-ray muon exposure rate in non-walled concrete buildings.

    PubMed

    Fujitaka, K; Abe, S

    1984-06-01

    Computer simulations on the exposure indoors from cosmic ray muons were practiced in the framework of non-scattering and non-cascade assumptions. The model buildings were two-dimensional, rectangular, and were made of a normal concrete. A stratified structure was assumed in each building, where no mezzanine was considered. Walls were not taken into account yet. The distributions of the exposure rates in 26-story buildings were illustrated in contour maps for various sets of parameters. All of them gave basically archlike patterns. Analyses of the results showed that the exposure rate is affected most largely by the floor board thickness. The ceiling height would be an insignificant factor for short buildings. The min/max ratio of the muon exposure rate in a moderate size building was estimated to be more than 0.7.

  16. Muons in gamma showers

    NASA Technical Reports Server (NTRS)

    Stanev, T.; Vankov, C. P.; Halzen, F.

    1985-01-01

    Muon production in gamma-induced air showers, accounting for all major processes. For muon energies in the GeV region the photoproduction is by far the most important process, while the contribution of micron + micron pair creation is not negligible for TeV muons. The total rate of muons in gamma showers is, however, very low.

  17. Muon muon collider: Feasibility study

    SciTech Connect

    1996-06-18

    A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup {minus}2} s{sup {minus}1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice--the authors believe--to allow them to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring which has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design.

  18. Experimental Neutron Capture Rate Constraint Far from Stability.

    PubMed

    Liddick, S N; Spyrou, A; Crider, B P; Naqvi, F; Larsen, A C; Guttormsen, M; Mumpower, M; Surman, R; Perdikakis, G; Bleuel, D L; Couture, A; Crespo Campo, L; Dombos, A C; Lewis, R; Mosby, S; Nikas, S; Prokop, C J; Renstrom, T; Rubio, B; Siem, S; Quinn, S J

    2016-06-17

    Nuclear reactions where an exotic nucleus captures a neutron are critical for a wide variety of applications, from energy production and national security, to astrophysical processes, and nucleosynthesis. Neutron capture rates are well constrained near stable isotopes where experimental data are available; however, moving far from the valley of stability, uncertainties grow by orders of magnitude. This is due to the complete lack of experimental constraints, as the direct measurement of a neutron-capture reaction on a short-lived nucleus is extremely challenging. Here, we report on the first experimental extraction of a neutron capture reaction rate on ^{69}Ni, a nucleus that is five neutrons away from the last stable isotope of Ni. The implications of this measurement on nucleosynthesis around mass 70 are discussed, and the impact of similar future measurements on the understanding of the origin of the heavy elements in the cosmos is presented.

  19. High rate, fast timing Glass RPC for the high η CMS muon detectors

    NASA Astrophysics Data System (ADS)

    Gouzevitch, M.; Lagarde, F.; Laktineh, I.; Buridon, V.; Chen, X.; Combaret, C.; Eynard, A.; Germani, L.; Grenier, G.; Mathez, H.; Mirabito, L.; Petrukhin, A.; Steen, A.; Tromeur, W.; Wang, Y.; Gong, A.; Moreau, N.; Taille, C. de la; Dulucq, F.

    2017-02-01

    The HL-LHC phase is designed to increase by an order of magnitude the amount of data to be collected by the LHC experiments. To achieve this goal in a reasonable time scale the instantaneous luminosity would also increase by an order of magnitude up to 6 ·1034cm-2s-1 . The region of the forward muon spectrometer (| η | > 1.6) is not equipped with RPC stations. The increase of the expected particles rate up to 2 kHz/cm2 (including a safety factor 3) motivates the installation of RPC chambers to guarantee redundancy with the CSC chambers already present. The actual RPC technology of CMS cannot sustain the expected background level. A new generation Glass-RPC (GRPC) using low resistivity glass (LR) is proposed to equip at least the two most far away of the four high eta muon stations of CMS Butler et al. (2015). The design of small size prototypes and the studies of their performances under high rate particles flux is presented.

  20. High rate, fast timing Glass RPC for the high η CMS muon detectors

    NASA Astrophysics Data System (ADS)

    Lagarde, F.; Gouzevitch, M.; Laktineh, I.; Buridon, V.; Chen, X.; Combaret, C.; Eynard, A.; Germani, L.; Grenier, G.; Mathez, H.; Mirabito, L.; Petrukhin, A.; Steen, A.; Tromeur, W.; Wang, Y.; Gong, A.; Moreau, N.; de la Taille, C.; Dulucq, F.; Cimmino, A.; Crucy, S.; Fagot, A.; Gul, M.; Rios, A. A. O.; Tytgat, M.; Zaganidis, N.; Aly, S.; Assran, Y.; Radi, A.; Sayed, A.; Singh, G.; Abbrescia, M.; Iaselli, G.; Maggi, M.; Pugliese, G.; Verwilligen, P.; Van Doninck, W.; Colafranceschi, S.; Sharma, A.; Benussi, L.; Bianco, S.; Piccolo, D.; Primavera, F.; Bhatnagar, V.; Kumari, R.; Mehta, A.; Singh, J.; Ahmad, A.; Ahmed, W.; Asghar, H. M. I.; Awan, I. M.; Hoorani, R.; Muhammad, S.; Shahzad, H.; Shah, M. A.; Cho, S. W.; Choi, S. Y.; Hong, B.; Kang, M. H.; Lee, K. S.; Lim, J. H.; Park, S. K.; Kim, M. S.; Carpinteyro Bernardino, S.; Pedraza, I.; Uribe Estrada, C.; Carrillo Moreno, S.; Vazquez Valencia, F.; Pant, L. M.; Buontempo, S.; Cavallo, N.; Esposito, M.; Fabozzi, F.; Lanza, G.; Orso, I.; Lista, L.; Meola, S.; Merola, M.; Paolucci, P.; Thyssen, F.; Braghieri, A.; Magnani, A.; Montagna, P.; Riccardi, C.; Salvini, P.; Vai, I.; Vitulo, P.; Ban, Y.; Qian, S. J.; Choi, M.; Choi, Y.; Goh, J.; Kim, D.; Aleksandrov, A.; Hadjiiska, R.; Iaydjiev, P.; Rodozov, M.; Stoykova, S.; Sultanov, G.; Vutova, M.; Dimitrov, A.; Litov, L.; Pavlov, B.; Petkov, P.; Bagaturia, I.; Lomidze, D.; Avila, C.; Cabrera, A.; Sanabria, J. C.; Crotty, I.; Vaitkus, J.

    2016-09-01

    The HL-LHC phase is designed to increase by an order of magnitude the amount of data to be collected by the LHC experiments. To achieve this goal in a reasonable time scale the instantaneous luminosity would also increase by an order of magnitude up to 6 · 1034 cm-2s-1. The region of the forward muon spectrometer (|η| > 1.6) is not equipped with RPC stations. The increase of the expected particles flux up to 2 kHz/cm2 (including a safety factor 3) motivates the installation of RPC chambers to guarantee redundancy with the CSC chambers already present. The current CMS RPC technology cannot sustain the expected background level. The new technology that will be chosen should have a high rate capability and provide a good spatial and timing resolution. A new generation of Glass-RPC (GRPC) using low-resistivity glass is proposed to equip at least the two most far away of the four high η muon stations of CMS. First the design of small size prototypes and studies of their performance in high-rate particles flux are presented. Then the proposed designs for large size chambers and their fast-timing electronic readout are examined and preliminary results are provided.

  1. Multi-jet production rates in deep-inelastic muon-proton scattering

    SciTech Connect

    Salgado, C.W.

    1992-10-01

    Measurements of forward multi-jet production rates in deep-inelastic muonproton scattering are presented. Data were taken with a 490 GeV muon beam incident on a hydrogen target. Jets were defined using the JADE jet finding algorithm. The measured rates are presented as function of W, the hadronic center-of-mass energy and the jet resolution parameter, y[sub cut], in energies up to W=33 GeV. Good agreement is found in comparisons with predictions of the QCD-inspired Lund Monte Carlo models. Non-perturbative QCD production mechanisms, inside the Lund Model, can not reproduce the results for energies greater than W [approx equal] 20 GeV. Sensitivities of the jet rate measurements to the low x (x [approx equal] 0.02) gluon content of the nucleon and the evolution of [alpha][sub s], are studied.

  2. Multi-jet production rates in deep-inelastic muon-proton scattering

    SciTech Connect

    Salgado, C.W.; E665 Collaboration

    1992-10-01

    Measurements of forward multi-jet production rates in deep-inelastic muonproton scattering are presented. Data were taken with a 490 GeV muon beam incident on a hydrogen target. Jets were defined using the JADE jet finding algorithm. The measured rates are presented as function of W, the hadronic center-of-mass energy and the jet resolution parameter, y{sub cut}, in energies up to W=33 GeV. Good agreement is found in comparisons with predictions of the QCD-inspired Lund Monte Carlo models. Non-perturbative QCD production mechanisms, inside the Lund Model, can not reproduce the results for energies greater than W {approx_equal} 20 GeV. Sensitivities of the jet rate measurements to the low x (x {approx_equal} 0.02) gluon content of the nucleon and the evolution of {alpha}{sub s}, are studied.

  3. Effect of copper and aluminium on the event rate of cosmic ray muons at ground level in Bangi, Malaysia

    NASA Astrophysics Data System (ADS)

    Altameemi, Rasha N. I.; Gopir, G.

    2016-11-01

    In this study we determine the effect of aluminium (Al) and copper (Cu) shielding on the event rate of cosmic ray muons at ground level. The experiment was performed at Bangi in Malaysia with coordinates of 101.78° E, 2.92° N and elevation 30 m above sea level. Measurements were made along the vertical direction using muon telescopes (MTs) of parallel Geiger-Muller (GM) tubes with metal sheets above the MTs of up to 2.4 cm for Al and 2.7 cm for Cu. For these ranges of metal thicknesses, we find that the muon count rates increase linearly with the increase in metal thicknesses. The observed increase rate values are (0.18 ± 0.10) cm-1 and (0.26 ± 0.10)cm-1 for Al and Cu, respectively, with the larger value for Cu as expected from its higher atomic number and density. This indicates that for this thickness range, only the lower region of the Rossi curve is observed, with incoming cosmic ray muons producing charged particles in the metal layers, resulting in shower events or electromagnetic cascade. Thus, for this range of layer thickness, both aluminium and copper are not suitable to be used as shielding materials for ground level cosmic ray muons.

  4. Uncertainties in the calculation of solar-neutrino capture rates

    SciTech Connect

    Filippone, B.W.

    1981-01-01

    A detailed estimate is presented of the possible uncertainty range for the neutrino flux from a standard solar model. Using present estimated errors in the key input parameters, detailed solar models are calculated to give an uncertainty in the theoretical nu/sub e/ capture rate in both the on-going /sup 37/Cl experiment and the proposed experiment using /sup 71/Ga. The uncertainty in capture rate is investigated by considering individual parameter variations about a mean model, by simultaneously varying several key parameters to yield upper and lower limits, and by a Monte Carlo method.

  5. Jet rates from deep inelastic muon scattering in the W range of 15 to 35 GeV

    SciTech Connect

    Salgado, C.

    1991-08-01

    Production rates of forward jets in deep inelastic muon scattering are studied using the JADE jet finding algorithm. The evolution of di-jet rates with W is compared to QCD first order predictions in the W range of 15 to 25 GeV. 7 refs., 3 figs.

  6. Rate of Molecular Transfer of Allyl Alcohol across an AOT Surfactant Layer Using Muon Spin Spectroscopy.

    PubMed

    Jayasooriya, Upali A; Clayden, Nigel J; Steytler, David C; Oganesyan, Vasily S; Peck, Jamie N T; Khasanov, Rustem; Scheuermann, Robert; Stoykov, Alexey

    2016-01-26

    The transfer rate of a probe molecule across the interfacial layer of a water-in-oil (w/o) microemulsion was investigated using a combination of transverse field muon spin rotation (TF-μSR), avoided level crossing muon spin resonance (ALC-μSR), and Monte Carlo simulations. Reverse microemulsions consist of nanometer-sized water droplets dispersed in an apolar solvent separated by a surfactant monolayer. Although the thermodynamic, static model of these systems has been well described, our understanding of their dynamics is currently incomplete. For example, what is the rate of solute transfer between the aqueous and apolar solvents, and how this is influenced by the structure of the interface? With an appropriate choice of system and probe molecule, μSR offers a unique opportunity to directly probe these interfacial transfer dynamics. Here, we have employed a well characterized w/o microemulsion stabilized by bis(2-ethylhexyl) sodium sulfosuccinate (Aerosol OT), with allyl alcohol (CH2═CH-CH2-OH, AA) as the probe. Resonances due to both muoniated radicals, CMuH2-C*H-CH2-OH and C*H2-CHMu-CH2-OH, were observed with the former being the dominant species. All resonances displayed solvent dependence, with those in the microemulsion observed as a single resonance located at intermediate magnetic fields to those present in either of the pure solvents. Observation of a single resonance is strong evidence for interfacial transfer being in the fast exchange limit. Monte Carlo calculations of the ΔM = 0 ALC resonances are consistent with the experimental data, indicating exchange rates greater than 10(9) s(-1), placing the rate of interfacial transfer at the diffusion limit.

  7. SSC muon detector group report

    SciTech Connect

    Carlsmith, D.; Groom, D.; Hedin, D.; Kirk, T.; Ohsugi, T.; Reeder, D.; Rosner, J.; Wojcicki, S.

    1986-01-01

    We report here on results from the Muon Detector Group which met to discuss aspects of muon detection for the reference 4..pi.. detector models put forward for evaluation at the Snowmass 1986 Summer Study. We report on: suitable overall detector geometry; muon energy loss mechanisms; muon orbit determination; muon momentum and angle measurement resolution; raw muon rates and trigger concepts; plus we identify SSC physics for which muon detection will play a significant role. We conclude that muon detection at SSC energies and luminosities is feasible and will play an important role in the evolution of physics at the SSC.

  8. Muon Muon Collider: Feasibility Study

    SciTech Connect

    Gallardo, J.C.; Palmer, R.B.; Tollestrup, A.V.; Sessler, A.M.; Skrinsky, A.N.; Ankenbrandt, C.; Geer, S.; Griffin, J.; Johnstone, C.; Lebrun, P.; McInturff, A.; Mills, Frederick E.; Mokhov, N.; Moretti, A.; Neuffer, D.; Ng, K.Y.; Noble, R.; Novitski, I.; Popovic, M.; Qian, C.; Van Ginneken, A. /Fermilab /Brookhaven /Wisconsin U., Madison /Tel Aviv U. /Indiana U. /UCLA /LBL, Berkeley /SLAC /Argonne /Sobolev IM, Novosibirsk /UC, Davis /Munich, Tech. U. /Virginia U. /KEK, Tsukuba /DESY /Novosibirsk, IYF /Jefferson Lab /Mississippi U. /SUNY, Stony Brook /MIT /Columbia U. /Fairfield U. /UC, Berkeley

    2012-04-05

    A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design. Muons because of their large mass compared to an electron, do not produce significant synchrotron radiation. As a result there is negligible beamstrahlung and high energy collisions are not limited by this phenomena. In addition, muons can be accelerated in circular devices which will be considerably smaller than two full-energy linacs as required in an e{sup +} - e{sup -} collider. A hadron collider would require a CM energy 5 to 10 times higher than 4 TeV to have an equivalent energy reach. Since the accelerator size is limited by the strength of bending magnets, the hadron collider for the same physics reach would have to be much larger than the muon collider. In addition, muon collisions should be cleaner than hadron collisions. There are many detailed particle

  9. Leak Rate Test for a Fiber Beam Monitor Contained in a Vacuum for the Muon g-2 Experiment

    NASA Astrophysics Data System (ADS)

    O'Mara, Bridget; Lane, Noel; Gross, Eisen; Gray, Frederick; Muon g-2 Collaboration

    2014-09-01

    The muon g-2 experiment at Fermilab aims to measure the muon anomalous magnetic moment with a precision of 0.14 parts per million (ppm). The measurement will build on the Brookhaven-based E821 experiment, which yielded results suggesting new physics such as supersymmetry. The Fiber Beam Monitors (FBMs) are used in the experiment to determine the position and observe the motion of a muon beam and monitor the properties of the beam over time. The FBMs support a 9 cm × 8 cm ``harp'' with 7 scintillating fibers separated from each other by 13 mm, each with a diameter of 0.5 mm. The experiment requires a vacuum of less than 1 ×10-6 Torr to prevent trapping of electrons ionized from the residual gas by the electrostatic quadrupoles. To meet this requirement the FBMs must have a leak rate of less than 5 ×10-5 Torr L/s. We have constructed a vacuum system to simulate these conditions and have determined the leak rate of the FBMs within the constructed vacuum apparatus. This leak rate will be reported, along with preliminary results from tests of the light output from the scintillating fibers. The muon g-2 experiment at Fermilab aims to measure the muon anomalous magnetic moment with a precision of 0.14 parts per million (ppm). The measurement will build on the Brookhaven-based E821 experiment, which yielded results suggesting new physics such as supersymmetry. The Fiber Beam Monitors (FBMs) are used in the experiment to determine the position and observe the motion of a muon beam and monitor the properties of the beam over time. The FBMs support a 9 cm × 8 cm ``harp'' with 7 scintillating fibers separated from each other by 13 mm, each with a diameter of 0.5 mm. The experiment requires a vacuum of less than 1 ×10-6 Torr to prevent trapping of electrons ionized from the residual gas by the electrostatic quadrupoles. To meet this requirement the FBMs must have a leak rate of less than 5 ×10-5 Torr L/s. We have constructed a vacuum system to simulate these conditions

  10. Precision muon tracking detectors and read-out electronics for operation at very high background rates at future colliders

    NASA Astrophysics Data System (ADS)

    Kortner, O.; Kroha, H.; Nowak, S.; Richter, R.; Schmidt-Sommerfeld, K.; Schwegler, Ph.

    2016-07-01

    The experience of the ATLAS MDT muon spectrometer shows that drift-tube chambers provide highly reliable precision muon tracking over large areas. The ATLAS muon chambers are exposed to unprecedentedly high background of photons and neutrons induced by the proton collisions. Still higher background rates are expected at future high-energy and high-luminosity colliders beyond HL-LHC. Therefore, drift-tube detectors with 15 mm tube diameter (30 mm in ATLAS), optimised for high rate operation, have been developed for such conditions. Several such full-scale sMDT chambers have been constructed with unprecedentedly high sense wire positioning accuracy of better than 10 μm. The chamber design and assembly methods have been optimised for large-scale production, reducing considerably cost and construction time while maintaining the high mechanical accuracy and reliability. Tests at the Gamma Irradiation Facility at CERN showed that the rate capability of sMDT chambers is improved by more than an order of magnitude compared to the MDT chambers. By using read-out electronics optimised for high counting rates, the rate capability can be further increased.

  11. Telecommunication using muon beams

    DOEpatents

    Arnold, Richard C.

    1976-01-01

    Telecommunication is effected by generating a beam of mu mesons or muons, varying a property of the beam at a modulating rate to generate a modulated beam of muons, and detecting the information in the modulated beam at a remote location.

  12. Muon colliders and neutrino factories

    SciTech Connect

    Geer, S.; /Fermilab

    2010-09-01

    Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture and accelerate {Omicron}(10{sup 21}) muons/year. This development prepares the way for a new type of neutrino source (Neutrino Factory) and a new type of very high energy lepton-antilepton collider (Muon Collider). This article reviews the motivation, design and R&D for Neutrino Factories and Muon Colliders.

  13. Muon Colliders and Neutrino Factories

    SciTech Connect

    Geer, Steve; /Fermilab

    2009-11-01

    Over the past decade, there has been significant progress in developing the concepts and technologies needed to produce, capture, and accelerate {Omicron}(10{sup 21}) muons per year. These developments have paved the way for a new type of neutrino source (neutrino factory) and a new type of very high energy lepton-antilepton collider (muon collider). This article reviews the motivation, design, and research and development for future neutrino factories and muon colliders.

  14. Parametric control of collision rates and capture rates in geometrically enhanced differential immunocapture (GEDI) microfluidic devices for rare cell capture

    PubMed Central

    Smith, James P.; Lannin, Timothy B.; Syed, Yusef A.; Santana, Steven M.; Kirby, Brian J.

    2013-01-01

    The enrichment and isolation of rare cells from complex samples, such as circulating tumor cells (CTCs) from whole blood, is an important engineering problem with widespread clinical applications. One approach uses a microfluidic obstacle array with an antibody surface functionalization to both guide cells into contact with the capture surface and to facilitate adhesion; geometrically enhanced differential immunocapture is a design strategy in which the array is designed to promote target cell–obstacle contact and minimize other interactions (Gleghorn et al., 2010; Kirby et al., 2012). We present a simulation that uses capture experiments in a simple Hele-Shaw geometry (Santana et al., 2012) to inform a target-cell-specific capture model that can predict capture probability in immunocapture microdevices of any arbitrary complex geometry. We show that capture performance is strongly dependent on the array geometry, and that it is possible to select an obstacle array geometry that maximizes capture efficiency (by creating combinations of frequent target cell–obstacle collisions and shear stress low enough to support capture), while simulatenously enhancing purity by minimizing non-specific adhesion of both smaller contaminant cells (with infrequent cell–obstacle collisions) and larger contaminant cells (by focusing those collisions into regions of high shear stress). PMID:24078270

  15. Quasi-isochronous muon collection channels

    SciTech Connect

    Ankenbrandt, Charles M.; Neuffer, David; Johnson, Rolland P.

    2015-04-26

    Intense muon beams have many potential commercial and scientific applications, ranging from low-energy investigations of the basic properties of matter using spin resonance to large energy-frontier muon colliders. However, muons originate from a tertiary process that produces a diffuse swarm. To make useful beams, the swarm must be rapidly captured and cooled before the muons decay. In this STTR project a promising new concept for the collection and cooling of muon beams to increase their intensity and reduce their emittances was investigated, namely, the use of a nearly isochronous helical cooling channel (HCC) to facilitate capture of the muons into RF bunches. The muon beam can then be cooled quickly and coalesced efficiently to optimize the luminosity of a muon collider, or could provide compressed muon beams for other applications. Optimal ways to integrate such a subsystem into the rest of a muon collection and cooling system, for collider and other applications, were developed by analysis and simulation. The application of quasi-isochronous helical cooling channels (QIHCC) for RF capture of muon beams was developed. Innovative design concepts for a channel incorporating straight solenoids, a matching section, and an HCC, including RF and absorber, were developed, and its subsystems were simulated. Additionally, a procedure that uses an HCC to combine bunches for a muon collider was invented and simulated. Difficult design aspects such as matching sections between subsystems and intensity-dependent effects were addressed. The bunch recombination procedure was developed into a complete design with 3-D simulations. Bright muon beams are needed for many commercial and scientific reasons. Potential commercial applications include low-dose radiography, muon catalyzed fusion, and the use of muon beams to screen cargo containers for homeland security. Scientific uses include low energy beams for rare process searches, muon spin resonance applications, muon beams for

  16. NEUTRINO FACTORY BASED ON MUON-STORAGE-RINGS TO MUON COLLIDERS: PHYSICS AND FACILITIES.

    SciTech Connect

    PARSA,Z.

    2001-06-18

    Intense muon sources for the purpose of providing intense high energy neutrino beams ({nu} factory) represents very interesting possibilities. If successful, such efforts would significantly advance the state of muon technology and provides intermediate steps in technologies required for a future high energy muon collider complex. High intensity muon: production, capture, cooling, acceleration and multi-turn muon storage rings are some of the key technology issues that needs more studies and developments, and will briefly be discussed here. A muon collider requires basically the same number of muons as for the muon storage ring neutrino factory, but would require more cooling, and simultaneous capture of both {+-} {mu}. We present some physics possibilities, muon storage ring based neutrino facility concept, site specific examples including collaboration feasibility studies, and upgrades to a full collider.

  17. Enhanced capture rate for haze defects in production wafer inspection

    NASA Astrophysics Data System (ADS)

    Auerbach, Ditza; Shulman, Adi; Rozentsvige, Moshe

    2010-03-01

    involved scanning with three different recipe types: Standard Inspection: Nominal recipe with a low false alarm rate was used to scan the wafer and repeaters were extracted from the final defect map. Haze Monitoring Application: Recipe sensitivity was enhanced and run on a single field column from which on repeating defects were extracted. Enhanced Repeater Extractor: Defect processing included the two parallel routes: a nominal recipe for the random defects and the new high sensitive repeater extractor algorithm. The results showed that the new application (recipe #3) had the highest capture rate on haze defects and detected new repeater defects not found in the first two recipes. In addition, the recipe was much simpler to setup since repeaters are filtered separately from random defects. We expect that in the future, with the advent of mask-less lithography and EUV lithography, the monitoring of field and die repeating defects on the wafer will become a necessity for process control in the semiconductor fab.

  18. Muon colliders

    NASA Astrophysics Data System (ADS)

    Palmer, R. B.; Sessler, A.; Skrinsky, A.; Tollestrup, A.; Baltz, A. J.; Chen, P.; Cheng, W.-H.; Cho, Y.; Courant, E.; Fernow, R. C.; Gallardo, J. C.; Garren, A.; Green, M.; Kahn, S.; Kirk, H.; Lee, Y. Y.; Mills, F.; Mokhov, N.; Morgan, G.; Neuffer, D.; Noble, R.; Norem, J.; Popovic, M.; Schachinger, L.; Silvestrov, G.; Summers, D.; Stumer, I.; Syphers, M.; Torun, Y.; Trbojevic, D.; Turner, W.; Van Ginneken, A.; Vsevolozhskaya, T.; Weggel, R.; Willen, E.; Winn, D.; Wurtele, J.

    1996-05-01

    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity μ+μ- colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Problems of detector background are also discussed.

  19. Muon colliders

    SciTech Connect

    Palmer, R.B. |; Sessler, A.; Skrinsky, A.

    1996-01-01

    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity {micro}{sup +}{micro}{sup {minus}}colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Problems of detector background are also discussed.

  20. Factors influencing the variation in capture rates of shrews in southern California, USA

    USGS Publications Warehouse

    Laakkonen, Juha; Fisher, Robert N.; Case, Ted J.

    2003-01-01

    We examined the temporal variation in capture rates of shrewsNotiosorex crawfordi (Coues, 1877) and Sorex ornatus (Merriam, 1895) in 20 sites representing fragmented and continuous habitats in southern California, USA. InN. crawfordi, the temporal variation was significantly correlated with the mean capture rates. Of the 6 landscape variables analyzed (size of the landscape, size of the sample area, altitude, edge, longitude and latitude), sample area was positively correlated with variation in capture rates ofN. crawfordi. InS. ornatus, longitude was negatively correlated with variation in capture rates. Analysis of the effect of precipitation on the short- and long-term capture rates at 2 of the sites showed no correlation between rainfall and capture rates of shrews even though peak number of shrews at both sites were reached during the year of highest amount of rainfall. A key problem confounding capture rates of shrews in southern California is the low overall abundance of both shrew species in all habitats and seasons.

  1. Precison Muon Physics

    NASA Astrophysics Data System (ADS)

    Hertzog, David

    2013-04-01

    The worldwide, vibrant experimental program involving precision measurements with muons will be presented. Recent achievements in this field have greatly improved our knowledge of fundamental parameters: Fermi constant (lifetime), weak-nucleon pseudoscalar coupling (μp capture), Michel decay parameters, and the proton charged radius (Lamb shift). The charged-lepton-violating decay μ->eγ sets new physics limits. Updated Standard Model theory evaluations of the muon anomalous magnetic moment has increased the significance beyond 3 σ for the deviation with respect to experiment. Next-generation experiments are mounting, with ambitious sensitivity goals for the muon-to-electron search approaching 10-17 sensitivity and for a 0.14 ppm determination of g-2. The broad physics reach of these efforts involves atomic, nuclear and particle physics communities. I will select from recent work and outline the most important efforts that are in preparation.

  2. Coping with mist-net capture-rate bias: Canopy height and several extrinsic factors

    USGS Publications Warehouse

    Mallory, Elizabeth P.; Brokaw, Nicholas V. L.; Hess, Steven C.

    2004-01-01

    Many factors other than a species' actual abundance can affect mist-net capture rates. We used ANCOVA models to quantify some potential biases and control their effects, producing adjusted estimates of capture rates that are more directly comparable among mist-net stations. Data came from 46 two-day mist-net sessions from September 1990 to May 1992 at six subtropical forest stations in the Rio Bravo Conservation and Management Area, northwest Belize. Factors evaluated included canopy height at net sites, long-term net shyness (days elapsed between first and last netting day of the entire study period), season (wet vs. dry), total rainfall during a netting session, and temperature. Number of individuals and species captured/10 net-h declined at each net with increasing canopy height above the net. Capture rates differed significantly among some of the stations. Elapsed days and rainfall caused significant bias in capture rates, which were statistically controlled within the ANCOVA, whereas season and temperature did not. Capture rates varied among sessions, but there was a slight and significant decline over the entire study period for all stations combined. Rainfall significantly depressed capture rates somewhat on a daily basis, but capture rates did not differ between wet and dry seasons. When we replaced the station variable in the ANCOVA with mean canopy height, the model was still highly significant, but did not explain as much of the variation in capture rates. Statistical analysis provides an objective means of interpreting data and estimating reliability, but only if statistical assumptions of the analyses are met. We discuss the need for including randomization in the experimental design, standardizing netting protocol, and quantifying sources of bias in the field, before ANCOVA or other parametric statistical techniques can be used to partition effects of biases.

  3. Muon-pair production by atmospheric muons in CosmoALEPH.

    PubMed

    Maciuc, F; Grupen, C; Hashim, N-O; Luitz, S; Mailov, A; Müller, A-S; Putzer, A; Sander, H-G; Schmeling, S; Schmelling, M; Tcaciuc, R; Wachsmuth, H; Ziegler, Th; Zuber, K

    2006-01-20

    Data from a dedicated cosmic ray run of the ALEPH detector were used in a study of muon trident production, i.e., muon pairs produced by muons. Here the overburden and the calorimeters are the target materials while the ALEPH time projection chamber provides the momentum measurements. A theoretical estimate of the muon trident cross section is obtained by developing a Monte Carlo simulation for muon propagation in the overburden and the detector. Two muon trident candidates were found to match the expected theoretical pattern. The observed production rate implies that the nuclear form factor cannot be neglected for muon tridents.

  4. The first muon beam from a new highly-intense DC muon source, MuSIC

    NASA Astrophysics Data System (ADS)

    Tran, Nam Hoai; MuSIC Collaboration

    2012-09-01

    A new DC muon source, MuSIC, is now under construction at Research Center for Nuclear Physics (RCNP), Osaka University, Japan. The MuSIC adopts a new pion/muon collection system and a curved transport solenoid. These techniques are important in realization of future muon programs such as the muon to electron conversion experiments (COMET/Mu2e), neutrino factories, and muon colliders. The pion capture magnet and a part of the transport solenoid have been built and beam tests were carried out to assess the MuSIC's performance. Muon lifetime measurements and muonic X-ray measurements have been used for estimation of muon yield of the MuSIC. The result indicates that the MuSIC would be one of the most intense DC muon beams in the world.

  5. Capture-recapture estimation of prebreeding survival rate for birds exhibiting delayed maturation

    USGS Publications Warehouse

    Nichols, J.D.; Spendelow, J.A.; Hines, J.E.

    1990-01-01

    Many species of seabirds exhibit delayed maturity and do not return to the natal colony to breed for several years after fledging. Capture-recapture studies are frequently conducted at such breeding colonies and often include marking of young birds. However, because of the absence of these birds from the natal colony during the first few years after banding, the data do not fit neatly into existing capture-recapture models. Here we present a method for estimating prebreeding survival rate from capture-recapture studies on species exhibiting such patterns of delayed maturation. We illustrate the method using data from a capture-recapture study of Roseate Terns (Sterna dougallii ) on Falkner Island, Connecticut. The method appears to work well and emphasizes the potential to tailor capture-recapture models to specific field situations.

  6. Predator-prey encounter and capture rates for plankton in turbulent environments

    NASA Astrophysics Data System (ADS)

    Pécseli, H. L.; Trulsen, J.; Fiksen, Ø.

    2012-08-01

    Turbulence plays an important role for predator-prey interactions in aquatic environments. In one sense turbulence benefits the predator by increasing its encounter rate with prey, but on the other hand it can benefit the prey by making them more difficult to catch. In the present study of this problem, a turbulent flow field is obtained by direct numerical solution of the Navier-Stokes equation. The analysis includes the effects of the turbulence on the encounter rate between passively moving predators and prey, and at the same time also models the capture probability depending on the relative turbulent motions of predator and prey. Analytical results for scaling laws for planktonic encounter and capture rates in turbulent environments are obtained in terms of the basic parameters for the problem, and the results are compared with related findings reported in the literature. For large values of the specific energy dissipation rates ɛ the turbulence reduces the capture probability significantly, in part also because the effective capture range reduces for increasing turbulence intensity. The results presented here predict the parameters for an optimum turbulence level for the predator capture rate. For enhanced turbulence levels sudden bursts in the space-time varying velocity field contribute to a noise level that can reduce the probability for capturing prey. We consider cases where the capture range of an organism is comparable to or smaller than the effective Kolmogorov length scale, as well as the opposite limit of larger capture ranges in the inertial range of the turbulence. The reference model assumes spherical interception volumes, but it is demonstrated that the results remain basically valid also for the case where these volumes are hemispherical or conical: the consequences of having a shape of the interception surface deviating from a sphere can be accounted for by an empirical scaling factor, which depends solely on the opening angle of the cone.

  7. Mesh size and bird capture rates in Mato Grosso do Sul State, Brazil.

    PubMed

    Piratelli, A

    2003-02-01

    Mist-nets alternating 36-mm and 61-mm mesh in woods and low vegetation of "cerrado" (Brazilian savanna) tested bird-capture efficiency relative to bird length and mass. Of 1,296 birds captured and 102 species, 785 (93 species) were with 36-m mesh and 511 (69 species) with 61-mm mesh. The 61-mm mesh improved capture rates only for some larger species; so, in general, 36-mm mesh mist-nets are more appropriate for field work in "cerrado" areas.

  8. Characterization of muon and gamma radiations at the PTOLEMY site

    NASA Astrophysics Data System (ADS)

    Betts, Susannah; Gentile, Charles; Tully, Chris; Zapata, Sandra; Chris Tully Collaboration

    2013-10-01

    PTOLEMY is an experimental project at Princeton Plasma Physics Laboratory designed to determine the present day number density of relic neutrinos through measurement of electrons produced from neutrino capture on tritium. The weak interaction cross section for relic neutrino interactions necessitates high sensitivity measurements that could be influenced by high energy particles, like muons and gamma ray photons, which induce nuclear transitions and secondary electrons. Muons produced from the collision of cosmic rays with atmospheric nuclei are a significant source of background radiation at and below Earth's surface. The muon flux is measured by the coincidence of minimum ionization radiation loss in two plastic scintillator paddles. The spectrum of gamma ray photons is measured using sodium iodide based scintillators. These measurements will provide a characterization of the background and rates at the PTOLEMY site.

  9. Using Muons to Image the Subsurface.

    SciTech Connect

    Bonal, Nedra; Cashion, Avery Ted; Cieslewski, Grzegorz; Dorsey, Daniel J.; Foris, Adam; Miller, Timothy J.; Roberts, Barry L; Su, Jiann-Cherng; Dreesen, Wendi; Green, J. Andrew; Schwellenbach, David

    2016-11-01

    Muons are subatomic particles that can penetrate the earth 's crust several kilometers and may be useful for subsurface characterization . The absorption rate of muons depends on the density of the materials through which they pass. Muons are more sensitive to density variation than other phenomena, including gravity, making them beneficial for subsurface investigation . Measurements of muon flux rate at differing directions provide density variations of the materials between the muon source (cosmic rays and neutrino interactions) and the detector, much like a CAT scan. Currently, muon tomography can resolve features to the sub-meter scale. This work consists of three parts to address the use of muons for subsurface characterization : 1) assess the use of muon scattering for estimating density differences of common rock types, 2 ) using muon flux to detect a void in rock, 3) measure muon direction by designing a new detector. Results from this project lay the groundwork for future directions in this field. Low-density objects can be detected by muons even when enclosed in high-density material like lead, and even small changes in density (e.g. changes due to fracturing of material) can be detected. Rock density has a linear relationship with muon scattering density per rock volume when this ratio is greater than 0.10 . Limitations on using muon scattering to assess density changes among common rock types have been identified. However, other analysis methods may show improved results for these relatively low density materials. Simulations show that muons can be used to image void space (e.g. tunnels) within rock but experimental results have been ambiguous . Improvements are suggested to improve imaging voids such as tunnels through rocks. Finally, a muon detector has been designed and tested to measure muon direction, which will improve signal-to-noise ratio and help address fundamental questions about the source of upgoing muons .

  10. Comparative capture rate responses of mosquito vectors to light trap and human landing collection methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Landing rates (LR) of female Anopheles quadrimaculatus, Culex nigripalpus, Cx. quinquefasciatus, Ochlerotatus triseriatus and Aedes albopictus on human hosts were compared with capture rates responses by the same species to CDC-type light traps (LT) augmented with CO2. A significant relationship be...

  11. What does the muon spin-relaxation rate measure in 4f paramagnets with strong crystal fields and weak inter-site correlations?

    NASA Astrophysics Data System (ADS)

    Dalmas de Réotier, P.; Yaouanc, A.; Bonville, P.

    1996-07-01

    We investigate the physical meaning of the longitudinal muon spin-relaxation rate 0953-8984/8/27/020/img6 measured for a paramagnet at temperatures high with respect to the magnetic phase transition temperature. The depolarization rate 0953-8984/8/27/020/img6 is shown to be a function of the relaxation rates of the quasi-elastic and inelastic magnetic excitations. Using this analysis, we consider recently published 0953-8984/8/27/020/img8 data recorded on the strongly correlated electron systems CeNiSn and 0953-8984/8/27/020/img9.

  12. Muon Induced Spallation Neutrons in the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Orrell, J. L.; Ahmad, Q. R.; Hazama, R.; Wilkerson, J. F.

    2001-05-01

    Neutrons produced as spallation products from muon passage through the Sudbury Neutrino Observatory (SNO) are studied. Muons can produce spallation neutrons through inelastic scattering on nuclei. Thermalized neutrons capture on the deuterium in SNO's heavy water detector volume via d(n,γ)t. The γ-ray has an energy of 6.25-MeV and produces a detectable signal in the SNO detector. We show it is possible to extract a nearly pure sample of thermalized neutrons. The observed capture time and energy are used to confirm the events' identity as neutrons. The total detection efficiency for muon induced spallation of neutrons is estimated and used to calculate the total muon induced spallation rate of neutrons in the SNO detector. This rate will impact the analysis of the Neutral Current Detectors (NCDs). The NCDs are ^3He proportional counters which will be inserted into SNO and used to measure the neutral current reaction of neutrinos, d(ν_x,n)p, in SNO's heavy water.

  13. Gamow-Teller strength and lepton captures rates on 66‑71Ni in stellar matter

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Majid, Muhammad

    Charge-changing transitions play a significant role in stellar weak-decay processes. The fate of the massive stars is decided by these weak-decay rates including lepton (positron and electron) captures rates, which play a consequential role in the dynamics of core collapse. As per previous simulation results, weak interaction rates on nickel (Ni) isotopes have significant influence on the stellar core vis-à-vis controlling the lepton content of stellar matter throughout the silicon shell burning phases of high mass stars up to the presupernova stages. In this paper, we perform a microscopic calculation of Gamow-Teller (GT) charge-changing transitions, in the β-decay and electron capture (EC) directions, for neutron-rich Ni isotopes (66‑71Ni). We further compute the associated weak-decay rates for these selected Ni isotopes in stellar environment. The computations are accomplished by employing the deformed proton-neutron quasiparticle random phase approximation (pn-QRPA) model. A recent study showed that the deformed pn-QRPA theory is well suited for the estimation of GT transitions. The astral weak-decay rates are determined over densities in the range of 10-1011g/cm3 and temperatures in the range of 0.01 × 109-30 × 109K. The calculated lepton capture rates are compared with the previous calculation of Pruet and Fuller (PF). The overall comparison demonstrates that, at low stellar densities and high temperatures, our EC rates are bigger by as much as two orders of magnitude. Our results show that, at higher temperatures, the lepton capture rates are the dominant mode for the stellar weak rates and the corresponding lepton emission rates may be neglected.

  14. Comparative capture rate responses of mosquito vectors to light trap and human landing collection methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Capture rate responses of female Aedes albopictus Skuse, Anopheles quadrimaculatus Say, Culex nigripalpus Theobald, Culex quinquefasciatus Say, and Ochlerotatus triseriatus (Wiedemann) to CDC-type light trap (LT) and human landing (HL) collection methods were observed and evaluated for congruency wi...

  15. Polarized muon beams for muon collider

    NASA Astrophysics Data System (ADS)

    Skrinsky, A. N.

    1996-11-01

    An option for the production of intense and highly polarized muon beams, suitable for a high-luminosity muon collider, is described briefly. It is based on a multi-channel pion-collection system, narrow-band pion-to-muon decay channels, proper muon spin gymnastics, and ionization cooling to combine all of the muon beams into a single bunch of ultimately low emittance.

  16. Simple estimation of thermal capture rates for ion-dipole collisions by canonical effective potential methods

    NASA Astrophysics Data System (ADS)

    Marković, Nikola; Nordholm, Sture

    1989-07-01

    Thermal capture rate coefficients are considered for collision partners which at long range interact by ion-dipole plus polarization potentials. The simple Langevin-Gioumousis-Stevenson theory is extended by mapping the true asymmetric multidimensional interaction potential onto an effective spherically symmetric potential obtained by analysis of canonical probability or flux equalities. Bound states are eliminated in the mapping as well as in the final rate coefficient. Capture rate coefficients are calculated for H 3+ ions colliding with HCl, CS and HCN in a model where the ion is represented as a point charge and the target as a diatomic molecule. Corresponding calculations are carried out using canonical variational transition state theory. The theoretical results are compared with corresponding results obtained in classical trajectory calculations wherein the diatomic target (HCl, CS or HCN) is modeled as two point charges.

  17. Capture locations and growth rates of Atlantic sturgeon in the Chesapeake Bay

    USGS Publications Warehouse

    Welsh, S.A.; Eyler, S.M.; Mangold, M.F.; Spells, A.J.

    2002-01-01

    Little information exists on temporal and spatial distributions of wild and hatchery-reared Atlantic sturgeon Acipenser oxyrinchus oxyrinchus in the Chesapeake Bay. Approximately 3,300 hatchery-reared Atlantic sturgeon comprised of two size groups were released into the Nanticoke River, a tributary of the Chesapeake Bay, on 8 July 1996. During January 1996-May 2000, 1099 Atlantic sturgeon were captured incidentally (i.e., bycatch) by commercial watermen in the Chesapeake Bay, including 420 hatchery-reared individuals. Wild and hatchery-reared Atlantic sturgeon were captured primarily in pound nets and gill nets. Biologists tagged each fish and recorded weight, length, and location of capture. Although two adults greater than 2000 mm fork length (FL) were captured in Maryland waters, wild sturgeon were primarily juveniles from Maryland and Virginia waters (415 and 259 individuals below 1000 mm FL, respectively). A growth rate of 0.565 mm/d (N = 15, SE = 0.081) was estimated for wild individuals (487-944 mm TL at release) at liberty from 30 to 622 d. The average growth of the group of hatchery-reared Atlantic sturgeon raised at 10??C exceeded that of the group raised at 17??C. Our distributional data based on capture locations are biased by fishery dependence and gear selectivity. These data are informative to managers, however, because commercial effort is widely distributed in the Chesapeake Bay, and little distributional data were available before this study.

  18. Efficacy of trap modifications for increasing capture rates of aquatic snakes in floating aquatic funnel traps

    USGS Publications Warehouse

    Halstead, Brian J.; Wylie, Glenn D.; Casazza, Michael L.

    2013-01-01

    Increasing detection and capture probabilities of rare or elusive herpetofauna of conservation concern is important to inform the scientific basis for their management and recovery. The Giant Gartersnake (Thamnophis gigas) is an example of a secretive, wary, and generally difficult-to-sample species about which little is known regarding its patterns of occurrence and demography. We therefore evaluated modifications to existing traps to increase the detection and capture probabilities of the Giant Gartersnake to improve the precision with which occurrence, abundance, survival, and other demographic parameters are estimated. We found that adding a one-way valve constructed of cable ties to the small funnel opening of traps and adding hardware cloth extensions to the wide end of funnels increased capture rates of the Giant Gartersnake by 5.55 times (95% credible interval = 2.45–10.51) relative to unmodified traps. The effectiveness of these modifications was insensitive to the aquatic habitat type in which they were deployed. The snout-vent length of the smallest and largest captured snakes did not vary among trap modifications. These trap modifications are expected to increase detection and capture probabilities of the Giant Gartersnake, and show promise for increasing the precision with which demographic parameters can be estimated for this species. We anticipate that the trap modifications found effective in this study will be applicable to a variety of aquatic and semi-aquatic reptiles and amphibians and improve conservation efforts for these species.

  19. High-Rate Data-Capture for an Airborne Lidar System

    NASA Technical Reports Server (NTRS)

    Valett, Susan; Hicks, Edward; Dabney, Philip; Harding, David

    2012-01-01

    A high-rate data system was required to capture the data for an airborne lidar system. A data system was developed that achieved up to 22 million (64-bit) events per second sustained data rate (1408 million bits per second), as well as short bursts (less than 4 s) at higher rates. All hardware used for the system was off the shelf, but carefully selected to achieve these rates. The system was used to capture laser fire, single-photon detection, and GPS data for the Slope Imaging Multi-polarization Photo-counting Lidar (SIMPL). However, the system has applications for other laser altimeter systems (waveform-recording), mass spectroscopy, xray radiometry imaging, high-background- rate ranging lidar, and other similar areas where very high-speed data capture is needed. The data capture software was used for the SIMPL instrument that employs a micropulse, single-photon ranging measurement approach and has 16 data channels. The detected single photons are from two sources those reflected from the target and solar background photons. The instrument is non-gated, so background photons are acquired for a range window of 13 km and can comprise many times the number of target photons. The highest background rate occurs when the atmosphere is clear, the Sun is high, and the target is a highly reflective surface such as snow. Under these conditions, the total data rate for the 16 channels combined is expected to be approximately 22 million events per second. For each photon detection event, the data capture software reads the relative time of receipt, with respect to a one-per-second absolute time pulse from a GPS receiver, from an event timer card with 0.1-ns precision, and records that information to a RAID (Redundant Array of Independent Disks) storage device. The relative time of laser pulse firings must also be read and recorded with the same precision. Each of the four event timer cards handles the throughput from four of the channels. For each detection event, a flag is

  20. Neutron Capture Rates near A=130 which Effect a Global Change to the r-Process Abundance Distribution

    SciTech Connect

    Surman, Rebecca; Beun, Joshua; Mclaughlin, Gail C; Hix, William Raphael

    2009-01-01

    We investigate the impact of neutron capture rates near the A=130 peak on the r-process abundance pattern. We show that these capture rates can alter the abundances of individual nuclear species, not only in the region of A=130 peak but also throughout the abundance pattern. We discuss in general the nonequilibrium processes that produce these abundance changes and determine which capture rates have the most significant impact.

  1. Determination of the neutron-capture rate of 17C for r -process nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Heine, M.; Typel, S.; Wu, M.-R.; Adachi, T.; Aksyutina, Y.; Alcantara, J.; Altstadt, S.; Alvarez-Pol, H.; Ashwood, N.; Atar, L.; Aumann, T.; Avdeichikov, V.; Barr, M.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boretzky, K.; Borge, M. J. G.; Burgunder, G.; Caamano, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkäll, J.; Chakraborty, S.; Chartier, M.; Chulkov, L. V.; Cortina-Gil, D.; Crespo, R.; Datta Pramanik, U.; Diaz Fernandez, P.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Freudenberger, M.; Fynbo, H. O. U.; Galaviz, D.; Geissel, H.; Gernhäuser, R.; Göbel, K.; Golubev, P.; Gonzalez Diaz, D.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heinz, A.; Henriques, A.; Holl, M.; Ickert, G.; Ignatov, A.; Jakobsson, B.; Johansson, H. T.; Jonson, B.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Knöbel, R.; Kröll, T.; Krücken, R.; Kurcewicz, J.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lepyoshkina, O.; Lindberg, S.; Machado, J.; Marganiec, J.; Martínez-Pinedo, G.; Maroussov, V.; Mostazo, M.; Movsesyan, A.; Najafi, A.; Neff, T.; Nilsson, T.; Nociforo, C.; Panin, V.; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Prochazka, A.; Rahaman, A.; Rastrepina, G.; Reifarth, R.; Ribeiro, G.; Ricciardi, M. V.; Rigollet, C.; Riisager, K.; Röder, M.; Rossi, D.; Sanchez del Rio, J.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Stoica, V.; Streicher, B.; Taylor, J. T.; Tengblad, O.; Terashima, S.; Thies, R.; Togano, Y.; Uberseder, E.; Van de Walle, J.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Weigand, M.; Wheldon, C.; Wilson, G.; Wimmer, C.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M. V.; Zilges, A.; Zuber, K.; R3B Collaboration

    2017-01-01

    With the R 3B -LAND setup at GSI we have measured exclusive relative-energy spectra of the Coulomb dissociation of 18C at a projectile energy around 425 A MeV on a lead target, which are needed to determine the radiative neutron-capture cross sections of 17C into the ground state of 18C. Those data have been used to constrain theoretical calculations for transitions populating excited states in 18C. This allowed to derive the astrophysical cross section σnγ * accounting for the thermal population of 17C target states in astrophysical scenarios. The experimentally verified capture rate is significantly lower than those of previously obtained Hauser-Feshbach estimations at temperatures T9≤ 1 GK. Network simulations with updated neutron-capture rates and hydrodynamics according to the neutrino-driven wind model as well as the neutron-star merger scenario reveal no pronounced influence of neutron capture of 17C on the production of second- and third-peak elements in contrast to earlier sensitivity studies.

  2. Rate-based process modeling study of CO{sub 2} capture with aqueous monoethanolamine solution

    SciTech Connect

    Zhang, Y.; Chen, H.; Chen, C.C.; Plaza, J.M.; Dugas, R.; Rochelle, G.T.

    2009-10-15

    Rate-based process modeling technology has matured and is increasingly gaining acceptance over traditional equilibrium-stage modeling approaches. Recently comprehensive pilot plant data for carbon dioxide (CO{sub 2}) capture with aqueous monoethanolamine (MEA) solution have become available from the University of Texas at Austin. The pilot plant data cover key process variables including CO{sub 2} concentration in the gas stream, CO{sub 2} loading in lean MEA solution, liquid to gas ratio, and packing type. In this study, we model the pilot plant operation with Aspen RateSep, a second generation rate-based multistage separation unit operation model in Aspen Plus. After a brief review of rate-based modeling, thermodynamic and kinetic models for CO{sub 2} absorption with the MEA solution, and transport property models, we show excellent match of the rate-based model predictions against the comprehensive pilot plant data and we validate the superiority of the rate-based models over the traditional equilibrium-stage models. We further examine the impacts of key rate-based modeling options, i.e., film discretization options and flow model options. The rate-based model provides excellent predictive capability, and it should be very useful for design and scale-up of CO{sub 2} capture processes.

  3. Electron-capture Rates for pf-shell Nuclei in Stellar Environments and Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Suzuki, Toshio; Honma, Michio; Mori, Kanji; Famiano, Michael A.; Kajino, Toshitaka; Hidakai, Jun; Otsuka, Takaharu

    Gamow-Teller strengths in pf-shell nuclei obtained by a new shell-model Hamltonian, GXPF1J, are used to evaluate electron-capture rates in pf-shell nuclei at stellar environments. The nuclear weak rates with GXPF1J, which are generally smaller than previous evaluations for proton-rich nuclei, are applied to nucleosynthesis in type Ia supernova explosions. The updated rates are found to lead to less production of neutron-rich nuclei such as 58Ni and 54Cr, thus toward a solution of the problem of over-production of neutron-rich isotopes of iron-group nuclei compared to the solar abundance.

  4. Fine-grid calculations for stellar electron and positron capture rates on Fe isotopes

    SciTech Connect

    Nabi, Jameel-Un; Tawfik, Abdel Nasser

    2013-03-15

    The acquisition of precise and reliable nuclear data is a prerequisite to success for stellar evolution and nucleosynthesis studies. Core-collapse simulators find it challenging to generate an explosion from the collapse of the core of massive stars. It is believed that a better understanding of the microphysics of core-collapse can lead to successful results. The weak interaction processes are able to trigger the collapse and control the lepton-to-baryon ratio (Y{sub e}) of the corematerial. It is suggested that the temporal variation of Y{sub e} within the core of a massive star has a pivotal role to play in the stellar evolution and a fine-tuning of this parameter at various stages of presupernova evolution is the key to generate an explosion. During the presupernova evolution of massive stars, isotopes of iron, mainly {sup 54-56}Fe, are considered to be key players in controlling Y{sub e} ratio via electron capture on these nuclides. Recently an improved microscopic calculation of weak-interaction-mediated rates for iron isotopes was introduced using the proton-neutron quasiparticle random-phase-approximation (pn-QRPA) theory. The pn-QRPA theory allows a microscopic state-by-state calculation of stellar capture rates which greatly increases the reliability of calculated rates. The results were suggestive of some fine-tuning of the Y{sub e} ratio during various phases of stellar evolution. Here we present for the first time the fine-grid calculation of the electron and positron capture rates on {sup 54-56}Fe. The sensitivity of the pn-QRPA calculated capture rates to the deformation parameter is also studied in this work. Core-collapse simulators may find this calculation suitable for interpolation purposes and for necessary incorporation in the stellar evolution codes.

  5. Rates for neutron-capture reactions on tungsten isotopes in iron meteorites. [Abstract only

    NASA Technical Reports Server (NTRS)

    Masarik, J.; Reedy, R. C.

    1994-01-01

    High-precision W isotopic analyses by Harper and Jacobsen indicate the W-182/W-183 ratio in the Toluca iron meteorite is shifted by -(3.0 +/- 0.9) x 10(exp -4) relative to a terrestrial standard. Possible causes of this shift are neutron-capture reactions on W during Toluca's approximately 600-Ma exposure to cosmic ray particles or radiogenic growth of W-182 from 9-Ma Hf-182 in the silicate portion of the Earth after removal of W to the Earth's core. Calculations for the rates of neutron-capture reactions on W isotopes were done to study the first possibility. The LAHET Code System (LCS) which consists of the Los Alamos High Energy Transport (LAHET) code and the Monte Carlo N-Particle(MCNP) transport code was used to numerically simulate the irradiation of the Toluca iron meteorite by galactic-cosmic-ray (GCR) particles and to calculate the rates of W(n, gamma) reactions. Toluca was modeled as a 3.9-m-radius sphere with the composition of a typical IA iron meteorite. The incident GCR protons and their interactions were modeled with LAHET, which also handled the interactions of neutrons with energies above 20 MeV. The rates for the capture of neutrons by W-182, W-183, and W-186 were calculated using the detailed library of (n, gamma) cross sections in MCNP. For this study of the possible effect of W(n, gamma) reactions on W isotope systematics, we consider the peak rates. The calculated maximum change in the normalized W-182/W-183 ratio due to neutron-capture reactions cannot account for more than 25% of the mass 182 deficit observed in Toluca W.

  6. A predator equalizes rate of capture of a schooling prey in a patchy environment.

    PubMed

    Vijayan, Sundararaj; Kotler, Burt P; Abramsky, Zvika

    2017-02-20

    Prey individuals are often distributed heterogeneously in the environment, and their abundances and relative availabilities vary among patches. A foraging predator should maximize energetic gains by selectively choosing patches with higher prey density. However, catching behaviorally responsive and group-forming prey in patchy environments can be a challenge for predators. First, they have to identify the profitable patches, and second, they must manage the prey's sophisticated anti-predator behavior. Thus, the forager and its prey have to continuously adjust their behavior to that of their opponent. Given these conditions, the foraging predator's behavior should be dynamic with time in terms of foraging effort and prey capture rates across different patches. Theoretically, the allocation of its time among patches of behaviorally responsive prey should be such that it equalizes its prey capture rates across patches through time. We tested this prediction in a model system containing a predator (little egret) and group-forming prey (common gold fish) in two sets of experiments in which (1) patches (pools) contained equal numbers of prey, or in which (2) patches contained unequal densities of prey. The egret equalized the prey capture rate through time in both equal and different density experiments.

  7. β+ Gamow-Teller transition strengths from 46Ti and stellar electron-capture rates.

    PubMed

    Noji, S; Zegers, R G T; Austin, Sam M; Baugher, T; Bazin, D; Brown, B A; Campbell, C M; Cole, A L; Doster, H J; Gade, A; Guess, C J; Gupta, S; Hitt, G W; Langer, C; Lipschutz, S; Lunderberg, E; Meharchand, R; Meisel, Z; Perdikakis, G; Pereira, J; Recchia, F; Schatz, H; Scott, M; Stroberg, S R; Sullivan, C; Valdez, L; Walz, C; Weisshaar, D; Williams, S J; Wimmer, K

    2014-06-27

    The Gamow-Teller strength in the β(+) direction to (46)Sc was extracted via the (46)Ti(t,(3)He + γ) reaction at 115  MeV/u. The γ-ray coincidences served to precisely measure the very weak Gamow-Teller transition to a final state at 991 keV. Although this transition is weak, it is crucial for accurately estimating electron-capture rates in astrophysical scenarios with relatively low stellar densities and temperatures, such as presupernova stellar evolution. Shell-model calculations with different effective interactions in the pf shell-model space do not reproduce the experimental Gamow-Teller strengths, which is likely due to sd-shell admixtures. Calculations in the quasiparticle random phase approximation that are often used in astrophysical simulations also fail to reproduce the experimental Gamow-Teller strength distribution, leading to strongly overestimated electron-capture rates. Because reliable theoretical predictions of Gamow-Teller strengths are important for providing astrophysical electron-capture reaction rates for a broad set of nuclei in the lower pf shell, we conclude that further theoretical improvements are required to match astrophysical needs.

  8. Calculation of the expected zero-field muon relaxation rate in the geometrically frustrated rare earth pyrochlore Gd(2)Sn(2)O(7) antiferromagnet.

    PubMed

    McClarty, P A; Cosman, J N; Del Maestro, A G; Gingras, M J P

    2011-04-27

    The magnetic insulator Gd(2)Sn(2)O(7) is one of many geometrically frustrated magnetic materials known to exhibit a nonzero muon spin polarization relaxation rate, λ(T), down to the lowest temperature (T) studied. Such behaviour is typically interpreted as signalling the presence of persistent spin dynamics (PSD) of the host material. In the case of Gd(2)Sn(2)O(7), such PSD comes as a surprise since magnetic specific heat measurements suggest conventional gapped magnons, which would naively lead to an exponentially vanishing λ(T) as T → 0. In contrast to most materials that display PSD, the ordered phase of Gd(2)Sn(2)O(7) is well characterized and both the nature and the magnitude of the interactions have been inferred from the magnetic structure and the temperature dependence of the magnetic specific heat. Based on this understanding, the temperature dependence of the muon spin polarization relaxation through the scattering of spin waves (magnons) is calculated. The result explicitly shows that, despite the unusual extensive number of weakly dispersive (gapped) excitations characterizing Gd(2)Sn(2)O(7), a remnant of the zero modes of the parent frustrated pyrochlore Heisenberg antiferromagnet, the temperature dependence of the calculated λ(T) differs dramatically from the experimental one. Indeed, the calculation conforms to the naive expectation of an exponential collapse of λ(T) at temperatures below ∼ 0.7 K. This result, for the first time, illustrates crisply and quantitatively the paradox that presents itself with the pervasive occurrence of PSD in highly frustrated magnetic systems as evinced by muon spin relaxation measurements.

  9. Measurement of the solar neutrino capture rate with gallium metal, part III

    SciTech Connect

    Elliott, Steven Ray

    2008-01-01

    The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in December 1989. Measurements have continued with only a few brief interruptions since that time. In this article we present the experimental improvements in SAGE since its last published data summary in December 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through December 2007 gives a capture rate of solar neutrinos with energy more than 233 keY of 65.4{sup +3.1}{sub 3.0} (stat) {sup +2.6}{sub -2.8} (syst) SNU. The weighted average of the results of all three Ga solar neUlrino experiments, SAGE, Gallex, and GNO, is now 66.1 {+-} 3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced {sup 37}Ar neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in the three prior {sup 51}Cr neutrino-source experiments with Ga, is 0.88 {+-} 0.05. A probable explanation for this low result is that the cross section for neutrino capture by the two lowest-lying excited states in {sup 71}Ge has been overestimated. If we assume these cross sections are zero, then the standard solar model including neutrino oscillations predicts a total capture rate in Ga in the range of 63--67 SNU with an uncertainly of about 5%, in good agreement with experiment. We derive the current value of the pp neutrino flux produced in the Sun to be {phi}{sup {circle_dot}}{sub pp} = (6.1 {+-} 0.8) x 10{sup 10}/(cm{sup 2} s), which agrees well with the flux predicted by the standard solar model. Finally, we make several tests and show that the data are consistent with the assumption that the solar neutrino production rate is constant in time.

  10. Developing a cosmic ray muon sampling capability for muon tomography and monitoring applications

    NASA Astrophysics Data System (ADS)

    Chatzidakis, S.; Chrysikopoulou, S.; Tsoukalas, L. H.

    2015-12-01

    In this study, a cosmic ray muon sampling capability using a phenomenological model that captures the main characteristics of the experimentally measured spectrum coupled with a set of statistical algorithms is developed. The "muon generator" produces muons with zenith angles in the range 0-90° and energies in the range 1-100 GeV and is suitable for Monte Carlo simulations with emphasis on muon tomographic and monitoring applications. The muon energy distribution is described by the Smith and Duller (1959) [35] phenomenological model. Statistical algorithms are then employed for generating random samples. The inverse transform provides a means to generate samples from the muon angular distribution, whereas the Acceptance-Rejection and Metropolis-Hastings algorithms are employed to provide the energy component. The predictions for muon energies 1-60 GeV and zenith angles 0-90° are validated with a series of actual spectrum measurements and with estimates from the software library CRY. The results confirm the validity of the phenomenological model and the applicability of the statistical algorithms to generate polyenergetic-polydirectional muons. The response of the algorithms and the impact of critical parameters on computation time and computed results were investigated. Final output from the proposed "muon generator" is a look-up table that contains the sampled muon angles and energies and can be easily integrated into Monte Carlo particle simulation codes such as Geant4 and MCNP.

  11. Neutrino induced muons in Soudan 2.

    SciTech Connect

    DeMuth, D. M.; Soudan 2 Collaboration

    1999-06-23

    The neutrino-induced muon rate underground has been measured at Soudan 2. To discriminate from the intense background of atmospheric muons we consider only the through-going muons which originate from horizontal direction ({minus}0.14 < cos{theta} < 0.14). We calculate the horizontal, neutrino-induced muon rate at Soudan 2 from an exposure of 1.23 x 10{sup 8} s as {Phi}{sub {nu}{mu}} = (3.45 {+-} 0.52 {+-} 0.61) x 10{sup {minus}13} (cm{sup 2} sr s){sup {minus}1}.

  12. Stellar electron capture rates on neutron-rich nuclei and their impact on stellar core collapse

    NASA Astrophysics Data System (ADS)

    Raduta, Ad. R.; Gulminelli, F.; Oertel, M.

    2017-02-01

    During the late stages of gravitational core-collapse of massive stars, extreme isospin asymmetries are reached within the core. Due to the lack of microscopic calculations of electron-capture (EC) rates for all relevant nuclei, in general simple analytic parametrizations are employed. We study here several extensions of these parametrizations, allowing for a temperature, electron density, and isospin dependence as well as for odd-even effects. The latter extra degrees of freedom considerably improve the agreement with large-scale microscopic rate calculations. We find, in particular, that the isospin dependence leads to a significant reduction of the global EC rates during core collapse with respect to fiducial results, where rates optimized on calculations of stable f p -shell nuclei are used. Our results indicate that systematic microscopic calculations and experimental measurements in the N ≈50 neutron-rich region are desirable for realistic simulations of the core collapse.

  13. Muon Observations

    NASA Astrophysics Data System (ADS)

    Duldig, Marc L.

    2000-07-01

    Muon observations are complementary to neutron monitor observations but there are some important differences in the two techniques. Unlike neutron monitors, muon telescope systems use coincidence techniques to obtain directional information about the arriving particle. Neutron monitor observations require simple corrections for pressure variations to compensate for the varying mass of atmospheric absorber over a site. In contrast, muon observations require additional corrections for the positive and negative temperature effects. Muon observations commenced many years before neutron monitors were constructed. Thus, muon data over a larger number of solar cycles is available to study solar modulation on anisotropies and other cosmic ray variations. The solar diurnal and semi-diurnal variations have been studied for many years. Using the techniques of Bieber and Chen it has been possible to derive the radial gradient, parallel mean-free path and symmetric latitude gradient of cosmic rays for rigidities <200 GV. The radial gradient varies with the 11-year solar activity cycle whereas the parallel mean-free path appears to vary with the 22-year solar magnetic cycle. The symmetric latitudinal gradient reverses at each solar polarity reversal. These results are in general agreement with predictions from modulation models. In undertaking these analyses the ratio of the parallel to perpendicular mean-free path must be assumed. There is strong contention in the literature about the correct value to employ but the results are sufficiently robust for this to be, at most, a minor problem. An asymmetric latitude gradient of highly variable nature has been found. These observations do not support current modulation models. Our view of the sidereal variation has undergone a revolution in recent times. Nagashima, Fujimoto and Jacklyn proposed a narrow Tail-In source anisotropy and separate Loss-Cone anisotropy as being responsible for the observed variations. A new analysis

  14. Muon dynamics in a toroidal sector magnet

    SciTech Connect

    Gallardo, J.C.; Fernow, R.C.; Palmer, R.B.

    1998-01-01

    The present scenario for the cooling channel in a high brightness muon collider calls for a quasi-continuous solenoidal focusing channel. The beam line consists of a periodic array of hydrogen absorbers immersed in a solenoid with alternating focusing field and rf linacs at the zero field points. Solenoids and toroidal sectors have a natural place in muon collider design given the large emittance of the beam and consequently, the large transverse momentum of the initial pion beam or the decay muon beam. Bent solenoids as shown were studied for use at the front end of the machine, as part of the capture channel and more recently as part of a diagnostic setup to measure the position and momentum of muons. The authors present a Hamiltonian formulation of muon dynamics in toroidal sector solenoids (bent solenoid).

  15. Muon spin relaxation studies of interstitial and molecular motion.

    PubMed

    Cox, S F

    1998-03-01

    The unusual methods of preparation and analysis of spin polarization in muSR spectroscopy, which exploit the unique properties of the positive muon, are introduced in this article. Following a summary overview of applications, particular attention is paid to the problem of spin-lattice relaxation for a muon experiencing a hyperfine interaction with a single unpaired electron. The specific cases considered are the interstitial diffusion of muonium--the 1-electron atom which may be considered as a light isotope of hydrogen-and the molecular dynamics of organic radicals labelled by muonium. Rate equations for the evolution of population in the hyperfine-coupled spin states are solved numerically for various relaxation mechanisms. The formalism is equally valid for conventional ESR studies of paramagnetic states but is pursued specifically to simulate T1-relaxation in muSR. The simulations are compared with literature data. Also treated is the case of intermittent hyperfine coupling, appropriate to electron capture and loss in semiconductors or soliton motion in polymers; for this, a Monte Carlo approach is used to simulate the muon response. (For low-dimensional motion, the relaxation function is not exponential, so that a unique value of T1 cannot be defined.) Finally, a proposal is made to implement muon-T1 measurements in the rotating frame; this is designed for the selective study of electronically diamagnetic muonium states (i.e., those without hyperfine coupling) in the presence of a paramagnetic muonium or radical fraction.

  16. Comparing the effectiveness of heat rate improvements in different coal-fired power plants utilizing carbon dioxide capture

    NASA Astrophysics Data System (ADS)

    Walsh, Martin Jeremy

    New Congressional legislation may soon require coal-fired power generators to pay for their CO2 emissions and capture a minimum level of their CO2 output. Aminebased CO2 capture systems offer plants the most technically proven and commercially feasible option for CO2 capture at this time. However, these systems require a large amount of heat and power to operate. As a result, amine-based CO2 capture systems significantly reduce the net power of any units in which they are installed. The Energy Research Center has compiled a list of heat rate improvements that plant operators may implement before installing a CO2 capture system. The goal of these improvements is to upgrade the performance of existing units and partially offset the negative effects of adding a CO2 capture system. Analyses were performed in Aspen Plus to determine the effectiveness of these heat rate improvements in preserving the net power and net unit heat rate (NUHR) of four different power generator units. For the units firing high-moisture sub-bituminous coal, the heat rate improvements reduced NUHR by an average of 13.69% across a CO 2 capture level range of 50% to 90%. For the units firing bituminous coal across the same CO2 capture range, the heat rate improvements reduced NUHR by an average of 12.30%. Regardless of the units' coal or steam turbine cycle type, the heat rate improvements preserved 9.7% to 11.0% of each unit's net power across the same CO2 capture range. In general, the heat rate improvements were found to be most effective in improving the performance of units firing high-moisture sub-bituminous. The effect of the CO2 capture system on these units and the reasons for the improvements' greater effectiveness in them are described in this thesis.

  17. LINACS FOR FUTURE MUON FACILITIES

    SciTech Connect

    Slawomir Bogacz, Rolland Johnson

    2008-10-01

    Future Muon Colliders (MC) and Neutrino Factories (NF) based on muon storage rings will require innovative linacs to: produce the muons, cool them, compress longi-tudinally and ‘shape’ them into a beam and finally to rap-idly accelerate them to multi-GeV (NF) and TeV (MC) energies. Each of these four linac applications has new requirements and opportunities that follow from the na-ture of the muon in that it has a short lifetime (τ = 2.2 μsec) in its own rest frame, it is produced in a tertiary process into a large emittance, and its electron, photon, and neutrino decay products can be more than an annoy-ance. As an example, for optimum performance, the linac repetition rates should scale inversely with the laboratory lifetime of the muon in its storage ring, something as high as 1 kHz for a 40 GeV Neutrino Factory or as low as 20 Hz for a 5 TeV Muon Collider. A superconducting 8 GeV Linac capable of CW operation is being studied as a ver-satile option for muon production [1] for colliders, facto-ries, and muon beams for diverse purposes. A linac filled with high pressure hydrogen gas and imbedded in strong magnetic fields has been proposed to rapidly cool muon beams [2]. Recirculating Linear Accelerators (RLA) are possible because muons do not generate significant syn-chrotron radiation even at extremely high energy and in strong magnetic fields. We will describe the present status of linacs for muon applications; in particular the longitu-dinal bunch compression in a single pass linac and multi-pass acceleration in the RLA, especially the optics and technical requirements for RLA designs, using supercon-ducting RF cavities capable of simultaneous acceleration of both μ+ and μ- species, with pulsed linac quadrupoles to allow the maximum number of passes. The design will include the optics for the multi-pass linac and droplet-shaped return arcs.

  18. Effects of Purge-Flow Rate on Microbubble Capture in Radial Arterial-Line Filters

    PubMed Central

    Herbst, Daniel P.

    2016-01-01

    Abstract: The process of microbubble filtration from blood is complex and highly dependent on the forces of flow and buoyancy. To protect the patient from air emboli, arterial-line filters commonly use a micropore screen, a large volume housing with purpose-built shape, and a purge port to trap, separate, and remove circulating microbubbles. Although it has been proposed that an insufficient buoyancy force renders the purge port ineffective at removing microbubbles smaller than 500 μm, this research attempts to investigate the purge flow of an arterial-line filter to better understand the microbubble removal function in a typical radial filter design. As its primary objective, the study aims to determine the effect of purge-flow rate on bubble capture using air bolus injections from a syringe pump with 22-gauge needle and Doppler ultrasound bubble detection. The measureable bubble size generated in the test circuit ranged between 30 and 500 μm, while purge flow was varied between .1 and .5 L/min for testing. Statistical analysis of the test data was handled using a repeated measures design with significance set at p < .05 level. Outcomes demonstrated that higher purge flows yielded higher bubble counts, but the effect of purge-flow rate on bubble capture decreased as bubble size increased. Results also showed that purge flow from the test filter was capable of capturing all bubble sizes being generated over the entire flow range tested, and confirms utility of the purge port in removing microbubbles smaller than 500 μm. By analyzing bubble counts in the purge flow of a typical radial-filter design, this study demonstrates that currently available micropore filter technology is capable of removing the size range of bubbles that commonly pass through modern pump-oxygenator systems and should continue to be considered during extracorporeal circulation as a measure to improve patient safety. PMID:27729703

  19. Effects of Purge-Flow Rate on Microbubble Capture in Radial Arterial-Line Filters.

    PubMed

    Herbst, Daniel P

    2016-09-01

    The process of microbubble filtration from blood is complex and highly dependent on the forces of flow and buoyancy. To protect the patient from air emboli, arterial-line filters commonly use a micropore screen, a large volume housing with purpose-built shape, and a purge port to trap, separate, and remove circulating microbubbles. Although it has been proposed that an insufficient buoyancy force renders the purge port ineffective at removing microbubbles smaller than 500 μm, this research attempts to investigate the purge flow of an arterial-line filter to better understand the microbubble removal function in a typical radial filter design. As its primary objective, the study aims to determine the effect of purge-flow rate on bubble capture using air bolus injections from a syringe pump with 22-gauge needle and Doppler ultrasound bubble detection. The measureable bubble size generated in the test circuit ranged between 30 and 500 μm, while purge flow was varied between .1 and .5 L/min for testing. Statistical analysis of the test data was handled using a repeated measures design with significance set at p < .05 level. Outcomes demonstrated that higher purge flows yielded higher bubble counts, but the effect of purge-flow rate on bubble capture decreased as bubble size increased. Results also showed that purge flow from the test filter was capable of capturing all bubble sizes being generated over the entire flow range tested, and confirms utility of the purge port in removing microbubbles smaller than 500 μm. By analyzing bubble counts in the purge flow of a typical radial-filter design, this study demonstrates that currently available micropore filter technology is capable of removing the size range of bubbles that commonly pass through modern pump-oxygenator systems and should continue to be considered during extracorporeal circulation as a measure to improve patient safety.

  20. Muon motion in titanium hydride

    NASA Technical Reports Server (NTRS)

    Kempton, J. R.; Petzinger, K. G.; Kossler, W. J.; Schone, H. E.; Hitti, B. S.; Stronach, C. E.; Adu, N.; Lankford, W. F.; Reilly, J. J.; Seymour, E. F. W.

    1988-01-01

    Motional narrowing of the transverse-field muon spin rotation signal was observed in gamma-TiH(x) for x = 1.83, 1.97, and 1.99. An analysis of the data for TiH1.99 near room temperature indicates that the mechanism responsible for the motion of the muon out of the octahedral site is thermally activated diffusion with an attempt frequency comparable to the optical vibrations of the lattice. Monte Carlo calculations to simulate the effect of muon and proton motion upon the muon field-correlation time were used to interpret the motional narrowing in TiH1.97 near 500 K. The interpretation is dependent upon whether the Bloembergen, Purcell, and Pound (BPP) theory or an independent spin-pair relaxation model is used to obtain the vacancy jump rate from proton NMR T1 measurements. Use of BPP theory shows that the field-correction time can be obtained if the rate of motion of the muon with respect to the rate of the motion for the protons is decreased. An independent spin-pair relaxation model indicates that the field-correlation time can be obtained if the rate of motion for the nearest-neighbor protons is decreased.

  1. Astrophysical reaction rates for {sup 58,60}Ni(n,{gamma}) from new neutron capture cross section measurements

    SciTech Connect

    Guber, K. H.; Derrien, H.; Leal, L. C.; Arbanas, G.; Wiarda, D.; Koehler, P. E.; Harvey, J. A.

    2010-11-15

    New neutron capture cross sections of {sup 58,60}Ni were measured in the energy range from 100 eV to 600 keV using the Oak Ridge Electron Linear Accelerator. The combination of these new neutron capture data with previous transmission data allowed a resonance analysis up to 900 keV using R-matrix theory. The theoretically determined direct capture cross sections were included in the analyses. From these resonance parameters and the direct capture contribution, new (n,{gamma}) astrophysical reaction rates were determined over the entire energy range needed by the latest stellar models describing the so-called weak s process.

  2. Rate-dependent interface capture beyond the coffee-ring effect

    NASA Astrophysics Data System (ADS)

    Li, Yanan; Yang, Qiang; Li, Mingzhu; Song, Yanlin

    2016-04-01

    The mechanism of droplet drying is a widely concerned fundamental issue since controlling the deposition morphology of droplet has significant influence on printing, biology pattern, self-assembling and other solution-based devices fabrication. Here we reveal a striking different kinetics-controlled deposition regime beyond the ubiquitous coffee-ring effect that suspended particles tend to kinetically accumulate at the air-liquid interface and deposit uniformly. As the interface shrinkage rate exceeds the particle average diffusion rate, particles in vertical evaporation flow will be captured by the descending surface, producing surface particle jam and forming viscous quasi-solid layer, which dramatically prevents the trapped particles from being transported to drop edge and results in uniform deposition. This simple, robust drying regime will provide a versatile strategy to control the droplet deposition morphology, and a novel direction of interface assembling for fabricating superlattices and high quality photonic crystal patterns.

  3. Rate-dependent interface capture beyond the coffee-ring effect

    PubMed Central

    Li, Yanan; Yang, Qiang; Li, Mingzhu; Song, Yanlin

    2016-01-01

    The mechanism of droplet drying is a widely concerned fundamental issue since controlling the deposition morphology of droplet has significant influence on printing, biology pattern, self-assembling and other solution-based devices fabrication. Here we reveal a striking different kinetics-controlled deposition regime beyond the ubiquitous coffee-ring effect that suspended particles tend to kinetically accumulate at the air-liquid interface and deposit uniformly. As the interface shrinkage rate exceeds the particle average diffusion rate, particles in vertical evaporation flow will be captured by the descending surface, producing surface particle jam and forming viscous quasi-solid layer, which dramatically prevents the trapped particles from being transported to drop edge and results in uniform deposition. This simple, robust drying regime will provide a versatile strategy to control the droplet deposition morphology, and a novel direction of interface assembling for fabricating superlattices and high quality photonic crystal patterns. PMID:27090820

  4. Age-specificity of black-capped chickadee survival rates: Analysis of capture-recapture data

    USGS Publications Warehouse

    Loery, G.; Pollock, K.H.; Nichols, J.D.; Hines, J.E.

    1987-01-01

    The ornithological literature indicates a widespread belief in two generalizations about the age-specificity of avian survival rates: (1) survival rates of young birds for some period following fledging are lower than those of adults, and (2) after reaching adulthood survival rates are constant for birds of all ages. There is a growing body of evidence in support of the first generalization, although little is known about how long the survival difference between young and adults lasts. This latter question can be addressed with capture-recapture or band recovery studies based on birds marked in the winter, but the inability to determine age in many species during winter has prevented the use of standard methods. There is very little evidence supporting the second generalization, and we are in need of methods and actual analyses that address this question. In the present paper we restate the two generalizations as hypotheses and test them using data from a wintering Black-capped Chickadee (Parus atricapillus) population in Connecticut, which has been studied by Loery for 26 yr. We use a cohort-based Jolly-Seber approach, which should be useful in other investigations of this nature. We found strong evidence of lower survival rates in 1st-yr birds than in adults, but could not determine whether this was the result of higher mortality rates, higher emigration rates, or a combination of the two. We also found evidence that survival rates of adult birds were not constant with age but decreased at a rate of ? 3.5%/yr. As adult birds are very faithful to their wintering areas, we believe that almost all this decrease can be attributed to an increase in mortality with age. Simulation results suggest that heterogeneity of capture probabilities could not explain the magnitude of the decrease in survival with age. Age-dependent tag loss is also discussed as an alternative explanation, but is dismissed as very unlikely in this situation. This analysis thus provides some of the

  5. Theoretical simulation of carrier capture and relaxation rates in quantum-dot semiconductor optical amplifiers

    SciTech Connect

    Wu, Yunhu; Zhang, Guoping; Guo, Ling; Qi, Guoqun; Li, Xiaoming

    2014-06-14

    Based on Auger scattering mechanism, carrier-carrier scattering dynamics between the two-dimensional carrier reservoir (also called wetting layer, i.e., WL) and the confined quantum dot ground and first excited state in quantum-dot semiconductor optical amplifiers (QD-SOAs) are investigated theoretically in this paper. The scattering rates for independent electron and hole densities are calculated. The results show an ultra-fast carrier capture (relaxation) rate up to 1 ps{sup −1}, and there is a complex dependence of the Coulomb scattering rates on the WL electron and hole densities. In addition, due to the different effective mass and the level distribution, the scattering rates for electron and hole are very different. Finally, in order to provide a direction to control (increase or decrease) the input current in realistic QD-SOA systems, a simple method is proposed to determine the trends of the carrier recovery rates with the WL carrier densities in the vicinity of the steady-state.

  6. Toward Capturing Momentary Changes of Heart Rate Variability by a Dynamic Analysis Method

    PubMed Central

    Zhang, Haoshi; Zhu, Mingxing; Zheng, Yue; Li, Guanglin

    2015-01-01

    The analysis of heart rate variability (HRV) has been performed on long-term electrocardiography (ECG) recordings (12~24 hours) and short-term recordings (2~5 minutes), which may not capture momentary change of HRV. In this study, we present a new method to analyze the momentary HRV (mHRV). The ECG recordings were segmented into a series of overlapped HRV analysis windows with a window length of 5 minutes and different time increments. The performance of the proposed method in delineating the dynamics of momentary HRV measurement was evaluated with four commonly used time courses of HRV measures on both synthetic time series and real ECG recordings from human subjects and dogs. Our results showed that a smaller time increment could capture more dynamical information on transient changes. Considering a too short increment such as 10 s would cause the indented time courses of the four measures, a 1-min time increment (4-min overlapping) was suggested in the analysis of mHRV in the study. ECG recordings from human subjects and dogs were used to further assess the effectiveness of the proposed method. The pilot study demonstrated that the proposed analysis of mHRV could provide more accurate assessment of the dynamical changes in cardiac activity than the conventional measures of HRV (without time overlapping). The proposed method may provide an efficient means in delineating the dynamics of momentary HRV and it would be worthy performing more investigations. PMID:26172953

  7. Neutron capture production rates of cosmogenic 60Co, 59Ni and 36Cl in stony meteorites

    NASA Technical Reports Server (NTRS)

    Spergel, M. S.; Reedy, R. C.; Lazareth, O. W.; Levy, P. W.

    1986-01-01

    Results for neutron flux calculations in stony meteoroids (of various radii and compositions) and production rates for Cl-36, Ni-59, and Co-60 are reported. The Ni-59/Co-60 ratio is nearly constant with depth in most meteorites: this effect is consistent with the neutron flux and capture cross section properties. The shape of the neutron flux energy spectrum, varies little with depth in a meteorite. The size of the parent meteorite can be determined from one of its fragments, using the Ni-59/Co-60 ratios, if the parent meteorite was less than 75 g/cm(2) in radius. If the parent meteorite was larger, a lower limit on the size of the parent meteorite can be determined from a fragment. In C3 chondrites this is not possible. In stony meteorites with R less than 50 g/cm(2) the calculated Co-60 production rates (mass less than 4 kg), are below 1 atom/min g-Co. The highest Co-60 production rates occur in stony meteorites with radius about 250 g/cm(2) (1.4 m across). In meteorites with radii greater than 400 g/cm(2), the maximum Co-60 production rate occurs at a depth of about 175 g/cm(2) in L-chondrite, 125 g/cm(2) in C3 chrondrite, and 190 g/cm(2) in aubrites.

  8. Simultaneous use of mark-recapture and radiotelemetry to estimate survival, movement, and capture rates

    USGS Publications Warehouse

    Powell, L.A.; Conroy, M.J.; Hines, J.E.; Nichols, J.D.; Krementz, D.G.

    2000-01-01

    Biologists often estimate separate survival and movement rates from radio-telemetry and mark-recapture data from the same study population. We describe a method for combining these data types in a single model to obtain joint, potentially less biased estimates of survival and movement that use all available data. We furnish an example using wood thrushes (Hylocichla mustelina) captured at the Piedmont National Wildlife Refuge in central Georgia in 1996. The model structure allows estimation of survival and capture probabilities, as well as estimation of movements away from and into the study area. In addition, the model structure provides many possibilities for hypothesis testing. Using the combined model structure, we estimated that wood thrush weekly survival was 0.989 ? 0.007 ( ?SE). Survival rates of banded and radio-marked individuals were not different (alpha hat [S_radioed, ~ S_banded]=log [S hat _radioed/ S hat _banded]=0.0239 ? 0.0435). Fidelity rates (weekly probability of remaining in a stratum) did not differ between geographic strata (psi hat=0.911 ? 0.020; alpha hat [psi11, psi22]=0.0161 ? 0.047), and recapture rates ( = 0.097 ? 0.016) banded and radio-marked individuals were not different (alpha hat [p_radioed, p_banded]=0.145 ? 0.655). Combining these data types in a common model resulted in more precise estimates of movement and recapture rates than separate estimation, but ability to detect stratum or mark-specific differences in parameters was week. We conducted simulation trials to investigate the effects of varying study designs on parameter accuracy and statistical power to detect important differences. Parameter accuracy was high (relative bias [RBIAS] <2 %) and confidence interval coverage close to nominal, except for survival estimates of banded birds for the 'off study area' stratum, which were negatively biased (RBIAS -7 to -15%) when sample sizes were small (5-10 banded or radioed animals 'released' per time interval). To provide

  9. Imaging the Subsurface with Upgoing Muons

    NASA Astrophysics Data System (ADS)

    Bonal, N.; Preston, L. A.; Schwellenbach, D.; Dreesen, W.; Green, A.

    2014-12-01

    We assess the feasibility of imaging the subsurface using upgoing muons. Traditional muon imaging focuses on more-prevalent downgoing muons. Muons are subatomic particles capable of penetrating the earth's crust several kilometers. Downgoing muons have been used to image the Pyramid of Khafre of Giza, various volcanoes, and smaller targets like cargo. Unfortunately, utilizing downgoing muons requires below-target detectors. For aboveground objects like a volcano, the detector is placed at the volcano's base and the top portion of the volcano is imaged. For underground targets like tunnels, the detector would have to be placed below the tunnel in a deeper tunnel or adjacent borehole, which can be costly and impractical for some locations. Additionally, detecting and characterizing subsurface features like voids from tunnels can be difficult. Typical characterization methods like sonar, seismic, and ground penetrating radar have shown mixed success. Voids have a marked density contrast with surrounding materials, so using methods sensitive to density variations would be ideal. High-energy cosmic ray muons are more sensitive to density variation than other phenomena, including gravity. Their absorption rate depends on the density of the materials through which they pass. Measurements of muon flux rate at differing directions provide density variations of the materials between the muon source (cosmic rays and neutrino interactions) and detector, much like a CAT scan. Currently, tomography using downgoing muons can resolve features to the sub-meter scale. We present results of exploratory work, which demonstrates that upgoing muon fluxes appear sufficient to achieve target detection within a few months. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  10. Mixture models for estimating the size of a closed population when capture rates vary among individuals

    USGS Publications Warehouse

    Dorazio, R.M.; Royle, J. Andrew

    2003-01-01

    We develop a parameterization of the beta-binomial mixture that provides sensible inferences about the size of a closed population when probabilities of capture or detection vary among individuals. Three classes of mixture models (beta-binomial, logistic-normal, and latent-class) are fitted to recaptures of snowshoe hares for estimating abundance and to counts of bird species for estimating species richness. In both sets of data, rates of detection appear to vary more among individuals (animals or species) than among sampling occasions or locations. The estimates of population size and species richness are sensitive to model-specific assumptions about the latent distribution of individual rates of detection. We demonstrate using simulation experiments that conventional diagnostics for assessing model adequacy, such as deviance, cannot be relied on for selecting classes of mixture models that produce valid inferences about population size. Prior knowledge about sources of individual heterogeneity in detection rates, if available, should be used to help select among classes of mixture models that are to be used for inference.

  11. Silicon meets cyclotron: muon spin resonance of organosilicon radicals.

    PubMed

    West, Robert; Samedov, Kerim; Percival, Paul W

    2014-07-21

    Muons, generated at a high-powered cyclotron, can capture electrons to form muonium atoms. Muon spin resonance spectra can be recorded for organosilyl radicals obtained by addition of muonium atoms to silylenes and silenes. We present a brief summary of progress in this new area since the first such experiments were reported in 2008.

  12. Helical Channel Design and Technology for Cooling of Muon Beams

    NASA Astrophysics Data System (ADS)

    Yonehara, K.; Derbenev, Y. S.; Johnson, R. P.

    2010-11-01

    Novel magnetic helical channel designs for capture and cooling of bright muon beams are being developed using numerical simulations based on new inventions such as helical solenoid (HS) magnets and hydrogen-pressurized RF (HPRF) cavities. We are close to the factor of a million six-dimensional phase space (6D) reduction needed for muon colliders. Recent experimental and simulation results are presented.

  13. The program in muon and neutrino physics: Superbeams, cold muon beams, neutrino factory and the muon collider

    SciTech Connect

    R. Raja et al.

    2001-08-08

    The concept of a Muon Collider was first proposed by Budker [10] and by Skrinsky [11] in the 60s and early 70s. However, there was little substance to the concept until the idea of ionization cooling was developed by Skrinsky and Parkhomchuk [12]. The ionization cooling approach was expanded by Neufer [13] and then by Palmer [14], whose work led to the formation of the Neutrino Factory and Muon Collider Collaboration (MC) [3] in 1995. The concept of a neutrino source based on a pion storage ring was originally considered by Koshkarev [18]. However, the intensity of the muons created within the ring from pion decay was too low to provide a useful neutrino source. The Muon Collider concept provided a way to produce a very intense muon source. The physics potential of neutrino beams produced by muon storage rings was investigated by Geer in 1997 at a Fermilab workshop [19, 20] where it became evident that the neutrino beams produced by muon storage rings needed for the muon collider were exciting on their own merit. The neutrino factory concept quickly captured the imagination of the particle physics community, driven in large part by the exciting atmospheric neutrino deficit results from the SuperKamiokande experiment. As a result, the MC realized that a Neutrino Factory could be an important first step toward a Muon Collider and the physics that could be addressed by a Neutrino Factory was interesting in its own right. With this in mind, the MC has shifted its primary emphasis toward the issues relevant to a Neutrino Factory. There is also considerable international activity on Neutrino Factories, with international conferences held at Lyon in 1999, Monterey in 2000 [21], Tsukuba in 2001 [22], and another planned for London in 2002.

  14. Muon simulations for Super-Kamiokande, KamLAND, and CHOOZ

    SciTech Connect

    Tang, Alfred; Horton-Smith, Glenn; Kudryavtsev, Vitaly A.; Tonazzo, Alessandra

    2006-09-01

    Muon backgrounds at Super-Kamiokande, KamLAND, and CHOOZ are calculated using MUSIC. A modified version of the Gaisser sea-level muon distribution and a well-tested Monte Carlo integration method are introduced. Average muon energy, flux, and rate are tabulated. Plots of average energy and angular distributions are given. Implications for muon tracker design in future experiments are discussed.

  15. Rate Equation Theory for Island Sizes and Capture Zone Areas in Submonolayer Deposition: Realistic Treatment of Spatial Aspects of Nucleation

    SciTech Connect

    Evans, J W; Li, M; Bartelt, M C

    2002-12-05

    Extensive information on the distribution of islands formed during submonolayer deposition is provided by the joint probability distribution (JPD) for island sizes, s, and capture zone areas, A. A key ingredient determining the form of the JPD is the impact of each nucleation event on existing capture zone areas. Combining a realistic characterization of such spatial aspects of nucleation with a factorization ansatz for the JPD, we provide a concise rate equation formulation for the variation with island size of both the capture zone area and the island density.

  16. CDF Run 2 muon system

    SciTech Connect

    C. M. Ginsburg

    2004-02-05

    The CDF muon detection system for Run 2 of the Fermilab Tevatron is described. Muon stubs are detected for |{eta}| < 1.5, and are matched to tracks in the central drift chamber at trigger level 1 for |{eta}| < 1.25. Detectors in the |{eta}| < 1 central region, built for previous runs, have been enhanced to survive the higher rate environment and closer bunch spacing (3.5 {micro}sec to 396 nsec) of Run 2. Azimuthal gaps in the central region have been filled in. New detectors have been added to extend the coverage from |{eta}| < 1 to |{eta}| < 1.5, consisting of four layers of drift chambers covered with matching scintillators for triggering. The Level 1 Extremely Fast Tracker supplies matching tracks with measured p{sub T} for the muon trigger. The system has been in operation for over 18 months. Operating experience and reconstructed data are presented.

  17. Muons probe strong hydrogen interactions with defective graphene.

    PubMed

    Riccò, Mauro; Pontiroli, Daniele; Mazzani, Marcello; Choucair, Mohammad; Stride, John A; Yazyev, Oleg V

    2011-11-09

    Here, we present the first muon spectroscopy investigation of graphene, focused on chemically produced, gram-scale samples, appropriate to the large muon penetration depth. We have observed an evident muon spin precession, usually the fingerprint of magnetic order, but here demonstrated to originate from muon-hydrogen nuclear dipolar interactions. This is attributed to the formation of CHMu (analogous to CH(2)) groups, stable up to 1250 K where the signal still persists. The relatively large signal amplitude demonstrates an extraordinary hydrogen capture cross section of CH units. These results also rule out the formation of ferromagnetic or antiferromagnetic order in chemically synthesized graphene samples.

  18. Muon radiography for exploration of Mars geology

    NASA Astrophysics Data System (ADS)

    Kedar, S.; Tanaka, H. K. M.; Naudet, C. J.; Jones, C. E.; Plaut, J. P.; Webb, F. H.

    2013-06-01

    Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays) to image the interior of large-scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

  19. Muon radiography for exploration of Mars geology

    NASA Astrophysics Data System (ADS)

    Kedar, S.; Tanaka, H. K. M.; Naudet, C. J.; Jones, C. E.; Plaut, J. P.; Webb, F. H.

    2012-10-01

    Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays) to image the interior of large scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

  20. Jet production in muon-proton and muon-nuclei scattering at Fermilab-E665

    SciTech Connect

    Salgado, C.W.; E665 Collaboration

    1993-08-01

    Measurements of multi-jet production rates from Muon-Proton Muon- Nuclei scattering at Fermilab-E665 are presented. Jet rates are defined by the JADE clustering algorithm. Rates in Muon-Proton deep-inelastic scattering are compared to perturbative Quantum Chromodynamics (PQCD) and Monte Carlo model predictions. We observe hadronic (2+1)-jet rates which are a factor of two higher than PQCD predictions at the partonic level. Preliminary results from jet production on heavy targets, in the shadowing region, show a suppression of the jet rates as compared to deuterium. The two- forward jet sample present higher suppression as compared to the one-forward jet sample.

  1. Origin of meteoritic stardust unveiled by a revised proton-capture rate of 17O

    NASA Astrophysics Data System (ADS)

    Lugaro, M.; Karakas, A. I.; Bruno, C. G.; Aliotta, M.; Nittler, L. R.; Bemmerer, D.; Best, A.; Boeltzig, A.; Broggini, C.; Caciolli, A.; Cavanna, F.; Ciani, G. F.; Corvisiero, P.; Davinson, T.; Depalo, R.; di Leva, A.; Elekes, Z.; Ferraro, F.; Formicola, A.; Fülöp, Zs.; Gervino, G.; Guglielmetti, A.; Gustavino, C.; Gyürky, Gy.; Imbriani, G.; Junker, M.; Menegazzo, R.; Mossa, V.; Pantaleo, F. R.; Piatti, D.; Prati, P.; Scott, D. A.; Straniero, O.; Strieder, F.; Szücs, T.; Takács, M. P.; Trezzi, D.

    2017-01-01

    Stardust grains recovered from meteorites provide high-precision snapshots of the isotopic composition of the stellar environment in which they formed 1 . Attributing their origin to specific types of stars, however, often proves difficult. Intermediate-mass stars of 4-8 solar masses are expected to have contributed a large fraction of meteoritic stardust 2,3 . Yet, no grains have been found with the characteristic isotopic compositions expected for such stars 4,5 . This is a long-standing puzzle, which points to serious gaps in our understanding of the lifecycle of stars and dust in our Galaxy. Here we show that the increased proton-capture rate of 17O reported by a recent underground experiment 6 leads to 17O/16O isotopic ratios that match those observed in a population of stardust grainsfor proton-burning temperatures of 60-80 MK. These temperatures are achieved at the base of the convective envelope during the late evolution of intermediate-mass stars of 4-8 solar masses 7-9 , which reveals them as the most likely site of origin of the grains. This result provides direct evidence that these stars contributed to the dust inventory from which the Solar System formed.

  2. Capture-recapture-adjusted prevalence rates of type 2 diabetes are related to social deprivation.

    PubMed

    Ismail, A A; Beeching, N J; Gill, G V; Bellis, M A

    1999-12-01

    We examined the prevalence of type 2 diabetes and social deprivation in one urban district in Liverpool from October 1995 to September 1996 inclusive. This area has a stable Caucasian population of 176, 682. Lists were made of all known diabetics attending six different medical points of contact during the year, and were condensed and aggregated to eliminate duplicates. From postcode data, each patient was assigned to residence in one of the 14 electoral wards in the district, for which demographic structure and standardized measures of social deprivation were known (Townsend index). The crude period prevalences of type 1 and type 2 diabetes were estimated for each ward. Crude prevalence data were then corrected by applying capture-recapture (CR) techniques to the different patient datasets to allow for undercount. The crude period prevalence (95%CI) of diabetes was 1.5% (1.4-1.5%), or 2585/176, 682. The mean age of people with diabetes was not significantly different between electoral wards. The crude period prevalence of type 2 diabetes within individual wards ranged from 0.4% (0.3-0.6%) in the least deprived area to 4.1% (3.6-4.6%) in the most deprived area. The corresponding range of CR-adjusted period prevalence rates of type 2 diabetes was from 3.2% (2.8-3.6%) to 6.7% (6.1-7.4%), and there was strong correlation between both crude and CR-adjusted prevalence and social deprivation in each ward (r=0.76, p<0.001 for crude; and r=0. 49, p<0.005 for CR-adjusted prevalence). There was no correlation between the crude or CR-adjusted period prevalence rates of type 1 diabetes and Townsend index (r=0.14, p=NS). This strong correlation between the prevalence of type 2 diabetes and social deprivation has important implications for the planning of health-care delivery.

  3. Muon Catalyzed Fusion

    NASA Technical Reports Server (NTRS)

    Armour, Edward A.G.

    2007-01-01

    Muon catalyzed fusion is a process in which a negatively charged muon combines with two nuclei of isotopes of hydrogen, e.g, a proton and a deuteron or a deuteron and a triton, to form a muonic molecular ion in which the binding is so tight that nuclear fusion occurs. The muon is normally released after fusion has taken place and so can catalyze further fusions. As the muon has a mean lifetime of 2.2 microseconds, this is the maximum period over which a muon can participate in this process. This article gives an outline of the history of muon catalyzed fusion from 1947, when it was first realised that such a process might occur, to the present day. It includes a description of the contribution that Drachrnan has made to the theory of muon catalyzed fusion and the influence this has had on the author's research.

  4. Jet production in muon scattering at Fermilab E665

    SciTech Connect

    Salgado, C.W.; E665 Collaboration

    1993-11-01

    Measurements of multi-jet production rates from Muon-Nucleon and Muon-Nuclei scattering at Fermilab-E665 are presented. Jet rates are defined by the JADE clustering algorithm. Rates in Muon-Nucleon deep-inelastic scattering are compared to Monte Carlo model predictions. Preliminary results from jet production on heavy targets, in the shadowing region, show a higher suppression of two-forward jets as compared to one-forward jet production.

  5. Front End and HFOFO Snake for a Muon Facility

    SciTech Connect

    Neuffer, D.; Alexahin, Y.

    2015-09-01

    A neutrino factory or muon collider requires the capture and cooling of a large number of muons. Scenarios for capture, bunching, phase-energy rotation and initial cooling of μ’s produced from a proton source target have been developed, for neutrino factory and muon collider scenarios. They require a drift section from the target, a bunching section and a $\\phi-\\delta E$ rotation section leading into the cooling channel. The currently preferred cooling channel design is an “HFOFO Snake” configuration that cools both $\\mu^+$ and $\\mu^-$ transversely and longitudinally. The status of the design is presented and variations are discussed.

  6. Relationship between mosquito (Diptera: Culicidae) landing rates on a human subject and numbers captured using CO2-baited light traps.

    PubMed

    Barnard, D R; Knue, G J; Dickerson, C Z; Bernier, U R; Kline, D L

    2011-06-01

    Capture rates of insectary-reared female Aedes albopictus (Skuse), Anopheles quadrimaculatus Say, Culex nigripalpus Theobald, Culex quinquefasciatus Say and Aedes triseriatus (Say) in CDC-type light traps (LT) supplemented with CO2 and using the human landing (HL) collection method were observed in matched-pair experiments in outdoor screened enclosures. Mosquito responses were compared on a catch-per-unit-effort basis using regression analysis with LT and HL as the dependent and independent variables, respectively. The average number of mosquitoes captured in 1 min by LT over a 24-h period was significantly related to the average number captured in 1 min by HL only for Cx. nigripalpus and Cx. quinquefasciatus. Patterns of diel activity indicated by a comparison of the mean response to LT and HL at eight different times in a 24-h period were not superposable for any species. The capture rate efficiency of LT when compared with HL was ≤15% for all mosquitoes except Cx. quinquefasciatus (43%). Statistical models of the relationship between mosquito responses to each collection method indicate that, except for Ae. albopictus, LT and HL capture rates are significantly related only during certain times of the diel period. Estimates of mosquito activity based on observations made between sunset and sunrise were most precise in this regard for An. quadrimaculatus and Cx. nigripalpus, as were those between sunrise and sunset for Cx. quinquefasciatus and Ae. triseriatus.

  7. Muon Emittance Exchange with a Potato Slicer

    SciTech Connect

    Summers, D. J.; Hart, T. L.; Acosta, J. G.; Cremaldi, L. M.; Oliveros, S. J.; Perera, L. P.; Neuffer, D. V.

    2015-04-15

    We propose a novel scheme for final muon ionization cooling with quadrupole doublets followed by emittance exchange in vacuum to achieve the small beam sizes needed by a muon collider. A flat muon beam with a series of quadrupole doublet half cells appears to provide the strong focusing required for final cooling. Each quadrupole doublet has a low beta region occupied by a dense, low Z absorber. After final cooling, normalized transverse, longitudinal, and angular momentum emittances of 0.100, 2.5, and 0.200 mm-rad are exchanged into 0.025, 70, and 0.0 mm-rad. A skew quadrupole triplet transforms a round muon bunch with modest angular momentum into a flat bunch with no angular momentum. Thin electrostatic septa efficiently slice the flat bunch into 17 parts. The 17 bunches are interleaved into a 3.7 meter long train with RF deflector cavities. Snap bunch coalescence combines the muon bunch train longitudinally in a 21 GeV ring in 55 µs, one quarter of a synchrotron oscillation period. A linear long wavelength RF bucket gives each bunch a different energy causing the bunches to drift in the ring until they merge into one bunch and can be captured in a short wavelength RF bucket with a 13% muon decay loss and a packing fraction as high as 87 %.

  8. Muon-to-Electron Conversion with COMET

    NASA Astrophysics Data System (ADS)

    Uchida, Y.

    2014-09-01

    The Coherent Muon-to-Electron Transition (COMET) experiment is presented, focusing on the particle detection systems. COMET is currently under construction as the first of two phases at the J-PARC proton accelerator laboratory in Tokai, Japan. COMET will search for muon-to-electron conversion with a single-event sensitivity of 2.6 × 10-17, with Phase-I achieving a sensitivity of 3.1 × 10-15 and due to enter commissioning in 2016. Phase-I will also allow us to study the novel pion and muon beamline and the rates of background processes.

  9. Relationship between mosquito (Diptera: Culicidae) landing rates on a human subject and numbers captured using CO2-baited light traps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Capture rates of female Aedes albopictus Skuse, Aedes triseriatus (Say), Anopheles quadrimaculatus Say, Culex nigripalpus Theobald, and Culex quinquefasciatus Say in CDC-type light traps supplemented with CO2 (LT) and using the human landing (HL) collection method were observed in matched-pair exper...

  10. A halo-independent lower bound on the dark matter capture rate in the Sun from a direct detection signal

    SciTech Connect

    Blennow, Mattias; Herrero-Garcia, Juan; Schwetz, Thomas

    2015-05-21

    We show that a positive signal in a dark matter (DM) direct detection experiment can be used to place a lower bound on the DM capture rate in the Sun, independent of the DM halo. For a given particle physics model and DM mass we obtain a lower bound on the capture rate independent of the local DM density, velocity distribution, galactic escape velocity, as well as the scattering cross section. We illustrate this lower bound on the capture rate by assuming that upcoming direct detection experiments will soon obtain a significant signal. When comparing the lower bound on the capture rate with limits on the high-energy neutrino flux from the Sun from neutrino telescopes, we can place upper limits on the branching fraction of DM annihilation channels leading to neutrinos. With current data from IceCube and Super-Kamiokande non-trivial limits can be obtained for spin-dependent interactions and direct annihilations into neutrinos. In some cases also annihilations into ττ or bb start getting constrained. For spin-independent interactions current constraints are weak, but they may become interesting for data from future neutrino telescopes.

  11. Muon cooling: longitudinal compression.

    PubMed

    Bao, Yu; Antognini, Aldo; Bertl, Wilhelm; Hildebrandt, Malte; Khaw, Kim Siang; Kirch, Klaus; Papa, Angela; Petitjean, Claude; Piegsa, Florian M; Ritt, Stefan; Sedlak, Kamil; Stoykov, Alexey; Taqqu, David

    2014-06-06

    A 10  MeV/c positive muon beam was stopped in helium gas of a few mbar in a magnetic field of 5 T. The muon "swarm" has been efficiently compressed from a length of 16 cm down to a few mm along the magnetic field axis (longitudinal compression) using electrostatic fields. The simulation reproduces the low energy interactions of slow muons in helium gas. Phase space compression occurs on the order of microseconds, compatible with the muon lifetime of 2  μs. This paves the way for the preparation of a high-quality low-energy muon beam, with an increase in phase space density relative to a standard surface muon beam of 10^{7}. The achievable phase space compression by using only the longitudinal stage presented here is of the order of 10^{4}.

  12. Approaches for the direct estimation of rate of increase in population size using capture-recapture data

    USGS Publications Warehouse

    Nichols, J.D.; Sillett, T. Scott; Hines, J.E.; Holmes, Richard T.; Ralph, C. John; Rich, Terrell D.

    2005-01-01

    Recent developments in the modeling of capture-recapture data permit the direct estimation and modeling of population growth rate Pradel (1996). Resulting estimates reflect changes in numbers of birds on study areas, and such changes result from movement as well as survival and reproductive recruitment. One measure of the 'importance' of a demographic vital rate to population growth is based on temporal covariation (i.e., do changes in population growth follow changes in vital rates). If data are available to estimate vital rates or their components, then such data can be combined with capture-recapture data in order to estimate parameters of the relationship between population growth and the vital rate. These methods are illustrated using capture-recapture and nest observation data for Black-throated Blue Warblers, Dendroica caerulescens, from a long-term study at Hubbard Brook Experimental Forest, New Hampshire, USA. Population growth rate was found to be positively associated with the proportion of birds that double-brood. We encourage use of these methods and believe they will prove to be very useful in research on, and management of, migratory bird populations.

  13. Multiple muons in MACRO

    NASA Technical Reports Server (NTRS)

    Heinz, R.

    1985-01-01

    An analysis of the multiple muon events in the Monopole Astrophysics and Cosmic Ray Observatory detector was conducted to determine the cosmic ray composition. Particular emphasis is placed on the interesting primary cosmic ray energy region above 2000 TeV/nucleus. An extensive study of muon production in cosmic ray showers has been done. Results were used to parameterize the characteristics of muon penetration into the Earth to the location of a detector.

  14. In a muon's lifetime: From Fermi's constant to ``calibrating'' the sun

    NASA Astrophysics Data System (ADS)

    Winter, Peter

    2010-10-01

    This presentation will cover three experiments at the Paul Scherrer Institute, Switzerland, all measuring the muon lifetime with high precision. The MuLan experiment [2] uses a simple soccer-ball like scintillator array to detect the positrons from the decay of positive muons. We collected twice 10^12 muon decays in two different target materials to obtain the final precision of 1 ppm for the lifetime. This determines the Fermi constant GF to 0.5 ppm precision [1]. The muon capture experiment MuCap uses a negative muon beam stopped in a time projection chamber as an active target filled with ultra-pure hydrogen gas. The elementary capture process μ^-+p -> n+ν offers a rare (0.15%) additional disappearance channel. The measured difference of the positive and negative muon's lifetime determines the rate of the capture process to a final precision of 1%. This can be used to derive an improved value of the proton's pseudoscalar form factor gP to 7% precision. A first result gP = 7.3 ± 1.1 has been published [3]. This is a first precise, unambigous determination of gP and an important test of QCD symmetries. Recently, we started a new experiment, MuSun [4] to measure the μ^-+d -> n+n+ν doublet capture rate. This measurement will provide a benchmark of the understanding of weak processes in the two nucleon-system. It was shown, that other weak reactions involving the two nucleon system (pp -> de^+ν or ν+d reactions) are related to the same low-energy constant, characterizing the two nucleon system at short distances. This constant is not well constrained and therefore the MuSun experiment comes closest to calibrating these basic astrophysical reactions under terrestrial conditions. [4pt] [1] In preparation for publication[0pt] [2] Phys. Rev. Lett. 99, 032001 (2007)[0pt] [3] Phys. Rev. Lett. 99, 032002 (2007)[0pt] [4] http://www.npl.uiuc.edu/exp/musun/documents/prop07.pdf

  15. Muon collider design

    NASA Astrophysics Data System (ADS)

    Palmer, R.; Sessler, A.; Skrinsky, A.; Tollestrup, A.; Baltz, A.; Caspi, S.; P., Chen; W-H., Cheng; Y., Cho; Cline, D.; Courant, E.; Fernow, R.; Gallardo, J.; Garren, A.; Gordon, H.; Green, M.; Gupta, R.; Hershcovitch, A.; Johnstone, C.; Kahn, S.; Kirk, H.; Kycia, T.; Y., Lee; Lissauer, D.; Luccio, A.; McInturff, A.; Mills, F.; Mokhov, N.; Morgan, G.; Neuffer, D.; K-Y., Ng; Noble, R.; Norem, J.; Norum, B.; Oide, K.; Parsa, Z.; Polychronakos, V.; Popovic, M.; Rehak, P.; Roser, T.; Rossmanith, R.; Scanlan, R.; Schachinger, L.; Silvestrov, G.; Stumer, I.; Summers, D.; Syphers, M.; Takahashi, H.; Torun, Y.; Trbojevic, D.; Turner, W.; van Ginneken, A.; Vsevolozhskaya, T.; Weggel, R.; Willen, E.; Willis, W.; Winn, D.; Wurtele, J.; Zhao, Y.

    1996-11-01

    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity \\mu^+ \\mu^- colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Detector background, polarization, and nonstandard operating conditions are discussed.

  16. Astrophysical reaction rates for Ni-58,Ni-60(n,gamma) from new neutron capture cross section measurements

    SciTech Connect

    Guber, Klaus H; Derrien, Herve; Leal, Luiz C; Arbanas, Goran; Wiarda, Dorothea; Koehler, Paul; Harvey, John A

    2010-01-01

    New neutron capture cross section of 58,60Ni were measured in the energy range from 100 eV to 600 keV using the Oak Ridge Electron Linear Accelerator (ORELA). The combination of these new neutron capture data with previous transmission data allowed a resonance analysis up to 900 keV using R-matrix theory. The theoretically determined direct capture (DC) cross sections were included in the analyses. From these resonance parameters and the DC contribution, new (n,y) astrophysical reaction rates were determined over the entire energy range needed by the lastest stellar models describing the so-called weak s process. PACS numbers: 25.40.Lw, 26.20Kn, 27.40.+z, 27.50.+e, 97.10.Cv

  17. Simulation of the High Performance Time to Digital Converter for the ATLAS Muon Spectrometer trigger upgrade

    NASA Astrophysics Data System (ADS)

    Meng, X. T.; Levin, D. S.; Chapman, J. W.; Zhou, B.

    2016-09-01

    The ATLAS Muon Spectrometer endcap thin-Resistive Plate Chamber trigger project compliments the New Small Wheel endcap Phase-1 upgrade for higher luminosity LHC operation. These new trigger chambers, located in a high rate region of ATLAS, will improve overall trigger acceptance and reduce the fake muon trigger incidence. These chambers must generate a low level muon trigger to be delivered to a remote high level processor within a stringent latency requirement of 43 bunch crossings (1075 ns). To help meet this requirement the High Performance Time to Digital Converter (HPTDC), a multi-channel ASIC designed by CERN Microelectronics group, has been proposed for the digitization of the fast front end detector signals. This paper investigates the HPTDC performance in the context of the overall muon trigger latency, employing detailed behavioral Verilog simulations in which the latency in triggerless mode is measured for a range of configurations and under realistic hit rate conditions. The simulation results show that various HPTDC operational configurations, including leading edge and pair measurement modes can provide high efficiency (>98%) to capture and digitize hits within a time interval satisfying the Phase-1 latency tolerance.

  18. Factors Influencing Male Plutella xylostella (Lepidoptera: Plutellidae) Capture Rates in Sex Pheromone-Baited Traps on Canola in Western Canada.

    PubMed

    Miluch, C E; Dosdall, L M; Evenden, M L

    2014-12-01

    Optimization of male moth trapping rates in sex pheromone-baited traps plays a key role in managing Plutella xylostella (L.). We investigated various ways to increase the attractiveness of pheromone-baited traps to P. xylostella in canola agroecosystems in AB, Canada. Factors tested included pheromone blend and dose, addition of a green leaf volatile to the pheromone at different times during the season, lure type, trap color, and height. The industry standard dose of 100 μg of pheromone (four-component blend) per lure (ConTech Enterprises Inc., Delta, British Columbia [BC], Canada) captured the most moths in the two lure types tested. Traps baited with pheromone released from gray rubber septa captured more males than those baited with red rubber septa. Traps baited with lures in which Z11-16: Ac is the main component attracted significantly more moths than those in which Z11-16: Ald is the main component. The addition of the green leaf volatile, (Z)-3-hexenyl acetate, to pheromone at a range of doses, did not increase moth capture at any point during the canola growing season. Unpainted white traps captured significantly more male moths than pheromone-baited traps that were painted yellow. Trap height had no significant effect on moth capture. Recommendations for monitoring P. xylostella in canola agroecosystems of western Canada include using a pheromone blend with Z11-16: Ac as the main component released from gray rubber septa at a dose of 100 μg.

  19. A coupled deterministic/stochastic method for computing neutron capture therapy dose rates

    NASA Astrophysics Data System (ADS)

    Hubbard, Thomas Richard

    Neutron capture therapy (NCT) is an experimental method of treating brain tumors and other cancers by: (1) injecting or infusing the patient with a tumor-seeking, neutron target-labeled drug; and (2) irradiating the patient in an intense epithermal neutron fluence. The nuclear reaction between the neutrons and the target nuclei (e.g. sp{10}B(n,alpha)sp7Lirbrack releases energy in the form of high-LET (i.e. energy deposited within the range of a cell diameter) reaction particles which selectively kill the tumor cell. The efficacy of NCT is partly dependent on the delivery of maximum thermal neutron fluence to the tumor and the minimization of radiation dose to healthy tissue. Since the filtered neutron source (e.g. research reactor) usually provides a broad energy spectrum of highly-penetrating neutron and gamma-photon radiation, detailed transport calculations are necessary in order to plan treatments that use optimal treatment facility configurations and patient positioning. Current computational methods for NCT use either discrete ordinates calculation or, more often, Monte Carlo simulation to predict neutron fluences in the vicinity of the tumor. These methods do not, however, accurately calculate the transport of radiation throughout the entire facility or the deposition of dose in all the various parts of the body due to shortcomings of using either method alone. A computational method, specifically designed for NCT problems, has been adapted from the MASH methodology and couples a forward discrete ordinates (Ssb{n}) calculation with an adjoint Monte Carlo run to predict the dose at any point within the patient. The transport from the source through the filter/collimator is performed with a forward DORT run, and this is then coupled to adjoint MORSE results at a selected coupling parallelepiped which surrounds human phantom. Another routine was written to allow the user to generate the MORSE models at various angles and positions within the treatment room. The

  20. MUON POLARIZATION IN A FRONT-END CHANNEL OF A NEUTRINO FACTORY.

    SciTech Connect

    FUKUI, Y.; FERNOW, R.C.; GALLARDO, J.C.

    2001-06-18

    As one of the figures of merit, muon polarization and its correlation to the particle arrival time was studied for the high intensity muon beam source of a Neutrino Factory. Muon polarization, 100% polarized in the parent pion rest system, was tracked down the pion capture, phase rotation, and ionization cooling channels, using the BMT equation. A study was done of the dependence of the muon polarization and its correlation on the configuration of induction linac channels in the phase rotation channel. Depolarization effects of the muon polarization through absorbers in the ionization cooling channel was simulated.

  1. Modification of magicity toward the dripline and its impact on electron-capture rates for stellar core collapse

    NASA Astrophysics Data System (ADS)

    Raduta, Ad. R.; Gulminelli, F.; Oertel, M.

    2016-02-01

    The importance of microphysical inputs from laboratory nuclear experiments and theoretical nuclear structure calculations in the understanding of core-collapse dynamics and the subsequent supernova explosion is largely recognized in the recent literature. In this work, we analyze the impact of the masses of very neutron-rich nuclei on the matter composition during collapse and the corresponding electron-capture rate. To this end, we introduce an empirical modification of the popular Duflo-Zuker mass model to account for possible shell quenching far from stability. We study the effect of this quenching on the average electron-capture rate. We show that the pre-eminence of the closed shells with N =50 and N =82 in the collapse dynamics is considerably decreased if the shell gaps are reduced in the region of 78Ni and beyond. As a consequence, local modifications of the overall electron-capture rate of up to 30% can be expected, depending on the strength of magicity quenching. This finding has potentially important consequences on the entropy generation, the neutrino emissivity, and the mass of the core at bounce. Our work underlines the importance of new experimental measurements in this region of the nuclear chart, the most crucial information being the nuclear mass and the Gamow-Teller strength. Reliable microscopic calculations of the associated elementary rate, in a wide range of temperatures and electron densities, optimized on these new empirical information, will be additionally needed to get quantitative predictions of the collapse dynamics.

  2. Statistical reconstruction for cosmic ray muon tomography.

    PubMed

    Schultz, Larry J; Blanpied, Gary S; Borozdin, Konstantin N; Fraser, Andrew M; Hengartner, Nicolas W; Klimenko, Alexei V; Morris, Christopher L; Orum, Chris; Sossong, Michael J

    2007-08-01

    Highly penetrating cosmic ray muons constantly shower the earth at a rate of about 1 muon per cm2 per minute. We have developed a technique which exploits the multiple Coulomb scattering of these particles to perform nondestructive inspection without the use of artificial radiation. In prior work [1]-[3], we have described heuristic methods for processing muon data to create reconstructed images. In this paper, we present a maximum likelihood/expectation maximization tomographic reconstruction algorithm designed for the technique. This algorithm borrows much from techniques used in medical imaging, particularly emission tomography, but the statistics of muon scattering dictates differences. We describe the statistical model for multiple scattering, derive the reconstruction algorithm, and present simulated examples. We also propose methods to improve the robustness of the algorithm to experimental errors and events departing from the statistical model.

  3. Muon and neutrino fluxes

    NASA Technical Reports Server (NTRS)

    Edwards, P. G.; Protheroe, R. J.

    1985-01-01

    The result of a new calculation of the atmospheric muon and neutrino fluxes and the energy spectrum of muon-neutrinos produced in individual extensive air showers (EAS) initiated by proton and gamma-ray primaries is reported. Also explained is the possibility of detecting atmospheric nu sub mu's due to gamma-rays from these sources.

  4. Detailed microscopic calculation of stellar electron and positron capture rates on 24Mg for O+Ne+Mg core simulations

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un

    2008-09-01

    A few white dwarfs, located in binary systems, may acquire sufficiently high mass-accretion rates resulting in the burning of carbon and oxygen under nondegenerate conditions forming an O+Ne+Mg core. These O+Ne+Mg cores are gravitationally less bound than more massive progenitor stars and can release more energy due to the nuclear burning. They are also amongst the probable candidates for low entropy r-process sites. Recent observations of subluminous Type II-P supernovae (e.g. 2005cs, 2003gd, 1999br and 1997D) were able to rekindle the interest in 8-10 Modot which develop O+Ne+Mg cores. Microscopic calculations of capture rates on 24Mg, which may contribute significantly to the collapse of O+Ne+Mg cores, using the shell model and the proton-neutron quasiparticle random-phase approximation (pn-QRPA) theory, were performed earlier and comparisons made. Simulators, however, may require these capture rates on a fine scale. For the first time, a detailed microscopic calculation of the electron and positron capture rates on 24Mg on an extensive temperature-density scale is presented here. This type of scale is more appropriate for interpolation purposes and of greater utility for simulation codes. The calculations are done using the pn-QRPA theory using a separable interaction. The deformation parameter, believed to be a key parameter in QRPA calculations, is adopted from experimental data to increase the reliability of the QRPA results further. The resulting calculated rates are up to a factor of 14 or more enhanced as compared to shell model rates and may lead to some interesting scenarios for core collapse simulators.

  5. Modelling the Effects of Prey Size and Distribution on Prey Capture Rates of Two Sympatric Marine Predators

    PubMed Central

    Thaxter, Chris B.; Daunt, Francis; Grémillet, David; Harris, Mike P.; Benvenuti, Silvano; Watanuki, Yutaka; Hamer, Keith C.; Wanless, Sarah

    2013-01-01

    Understanding how prey capture rates are influenced by feeding ecology and environmental conditions is fundamental to assessing anthropogenic impacts on marine higher predators. We compared how prey capture rates varied in relation to prey size, prey patch distribution and prey density for two species of alcid, common guillemot (Uria aalge) and razorbill (Alca torda) during the chick-rearing period. We developed a Monte Carlo approach parameterised with foraging behaviour from bird-borne data loggers, observations of prey fed to chicks, and adult diet from water-offloading, to construct a bio-energetics model. Our primary goal was to estimate prey capture rates, and a secondary aim was to test responses to a set of biologically plausible environmental scenarios. Estimated prey capture rates were 1.5±0.8 items per dive (0.8±0.4 and 1.1±0.6 items per minute foraging and underwater, respectively) for guillemots and 3.7±2.4 items per dive (4.9±3.1 and 7.3±4.0 items per minute foraging and underwater, respectively) for razorbills. Based on species' ecology, diet and flight costs, we predicted that razorbills would be more sensitive to decreases in 0-group sandeel (Ammodytes marinus) length (prediction 1), but guillemots would be more sensitive to prey patches that were more widely spaced (prediction 2), and lower in prey density (prediction 3). Estimated prey capture rates increased non-linearly as 0-group sandeel length declined, with the slope being steeper in razorbills, supporting prediction 1. When prey patches were more dispersed, estimated daily energy expenditure increased by a factor of 3.0 for guillemots and 2.3 for razorbills, suggesting guillemots were more sensitive to patchier prey, supporting prediction 2. However, both species responded similarly to reduced prey density (guillemot expenditure increased by 1.7; razorbill by 1.6), thus not supporting prediction 3. This bio-energetics approach complements other foraging models in predicting likely

  6. Modelling the effects of prey size and distribution on prey capture rates of two sympatric marine predators.

    PubMed

    Thaxter, Chris B; Daunt, Francis; Grémillet, David; Harris, Mike P; Benvenuti, Silvano; Watanuki, Yutaka; Hamer, Keith C; Wanless, Sarah

    2013-01-01

    Understanding how prey capture rates are influenced by feeding ecology and environmental conditions is fundamental to assessing anthropogenic impacts on marine higher predators. We compared how prey capture rates varied in relation to prey size, prey patch distribution and prey density for two species of alcid, common guillemot (Uria aalge) and razorbill (Alca torda) during the chick-rearing period. We developed a Monte Carlo approach parameterised with foraging behaviour from bird-borne data loggers, observations of prey fed to chicks, and adult diet from water-offloading, to construct a bio-energetics model. Our primary goal was to estimate prey capture rates, and a secondary aim was to test responses to a set of biologically plausible environmental scenarios. Estimated prey capture rates were 1.5 ± 0.8 items per dive (0.8 ± 0.4 and 1.1 ± 0.6 items per minute foraging and underwater, respectively) for guillemots and 3.7 ± 2.4 items per dive (4.9 ± 3.1 and 7.3 ± 4.0 items per minute foraging and underwater, respectively) for razorbills. Based on species' ecology, diet and flight costs, we predicted that razorbills would be more sensitive to decreases in 0-group sandeel (Ammodytes marinus) length (prediction 1), but guillemots would be more sensitive to prey patches that were more widely spaced (prediction 2), and lower in prey density (prediction 3). Estimated prey capture rates increased non-linearly as 0-group sandeel length declined, with the slope being steeper in razorbills, supporting prediction 1. When prey patches were more dispersed, estimated daily energy expenditure increased by a factor of 3.0 for guillemots and 2.3 for razorbills, suggesting guillemots were more sensitive to patchier prey, supporting prediction 2. However, both species responded similarly to reduced prey density (guillemot expenditure increased by 1.7; razorbill by 1.6), thus not supporting prediction 3. This bio-energetics approach complements other foraging models in

  7. Estimating Suicide Rates in Developing Nations: A Low-Cost Newspaper Capture-Recapture Approach in Cambodia.

    PubMed

    Harris, Keith M; Thandrayen, Joanne; Samphoas, Chien; Se, Pros; Lewchalermwongse, Boontriga; Ratanashevorn, Rattanakorn; Perry, Megan L; Britts, Choloe

    2016-04-01

    This study tested a low-cost method for estimating suicide rates in developing nations that lack adequate statistics. Data comprised reported suicides from Cambodia's 2 largest newspapers. Capture-recapture modeling estimated a suicide rate of 3.8/100 000 (95% CI = 2.5-6.7) for 2012. That compares to World Health Organization estimates of 1.3 to 9.4/100 000 and a Cambodian government estimate of 3.5/100 000. Suicide rates of males were twice that of females, and rates of those <40 years were twice that of those ≥40 years. Capture-recapture modeling with newspaper reports proved a reasonable method for estimating suicide rates for countries with inadequate official data. These methods are low-cost and can be applied to regions with at least 2 newspapers with overlapping reports. Means to further improve this approach are discussed. These methods are applicable to both recent and historical data, which can benefit epidemiological work, and may also be applicable to homicides and other statistics.

  8. Neutron-capture rates for explosive nucleosynthesis: the case of 68Ni(n, γ)69Ni

    NASA Astrophysics Data System (ADS)

    Spyrou, A.; Larsen, A. C.; Liddick, S. N.; Naqvi, F.; Crider, B. P.; Dombos, A. C.; Guttormsen, M.; Bleuel, D. L.; Couture, A.; Crespo Campo, L.; Lewis, R.; Mosby, S.; Mumpower, M. R.; Perdikakis, G.; Prokop, C. J.; Quinn, S. J.; Renstrøm, T.; Siem, S.; Surman, R.

    2017-04-01

    Neutron-capture reactions play an important role in heavy element nucleosynthesis, since they are the driving force for the two processes that create the vast majority of the heavy elements. When a neutron capture occurs on a short-lived nucleus, it is extremely challenging to study the reaction directly and therefore the use of indirect techniques is essential. The present work reports on such an indirect measurement that provides strong constraints on the 68Ni(n, γ)69Ni reaction rate. This is done by populating the compound nucleus 69Ni via the β decay of 69Co and measuring the γ-ray deexcitation of excited states in 69Ni. The β-Oslo method was used to extract the γ-ray strength function and the nuclear level density. In addition the half-life of 69Co was extracted and found to be in agreement with previous literature values. Before the present results, the 68Ni(n, γ)69Ni reaction was unconstrained and the purely theoretical reaction rate was highly uncertain. The new uncertainty on the reaction rate based on the present experiment (variation between upper and lower limit) is approximately a factor of 3. The commonly used reaction libraries JINA-REACLIB and BRUSLIB are in relatively good agreement with the experimental rate. The impact of the new rate on weak r-process calculations is discussed.

  9. Underwater measurements of muon intensity

    NASA Technical Reports Server (NTRS)

    Fedorov, V. M.; Pustovetov, V. P.; Trubkin, Y. A.; Kirilenkov, A. V.

    1985-01-01

    Experimental measurements of cosmic ray muon intensity deep underwater aimed at determining a muon absorption curve are of considerable interest, as they allow to reproduce independently the muon energy spectrum at sea level. The comparison of the muon absorption curve in sea water with that in rock makes it possible to determine muon energy losses caused by nuclear interactions. The data available on muon absorption in water and that in rock are not equivalent. Underground measurements are numerous and have been carried out down to the depth of approx. 15km w.e., whereas underwater muon intensity have been measured twice and only down to approx. 3km deep.

  10. THE POTENTIAL FOR NEUTRINO PHYSICS AT MUON COLLIDERS AND DEDICATED HIGH CURRENT MUON STORAGE RINGS

    SciTech Connect

    BIGI,I.; BOLTON,T.; FORMAGGIO,J.; HARRIS,D.; MORFIN,J.; SPENTZOURIS,P.; YU,J.; KAYSER,B.; KING,B.J.; MCFARLAND,K.; PETROV,A.; SCHELLMAN,H.; VELASCO,M.; SHROCK,R.

    2000-05-11

    Conceptual design studies are underway for both muon colliders and high-current non-colliding muon storage rings that have the potential to become the first true neutrino factories. Muon decays in long straight sections of the storage rings would produce uniquely intense and precisely characterized two-component neutrino beams--muon neutrinos plus electron antineutrinos from negative muon decays and electron neutrinos plus muon antineutrinos from positive muons. This article presents a long-term overview of the prospects for these facilities to greatly extend the capabilities for accelerator-based neutrino physics studies for both high rate and long baseline neutrino experiments. As the first major physics topic, recent experimental results involving neutrino oscillations have motivated a vigorous design effort towards dedicated neutrino factories that would store muon beams of energies 50 GeV or below. These facilities hold the promise of neutrino oscillation experiments with baselines up to intercontinental distances and utilizing well understood beams that contain, for the first time, a substantial component of multi-GeV electron-flavored neutrinos. In deference to the active and fast-moving nature of neutrino oscillation studies, the discussion of long baseline physics at neutrino factories has been limited to a concise general overview of the relevant theory, detector technologies, beam properties, experimental goals and potential physics capabilities. The remainder of the article is devoted to the complementary high rate neutrino experiments that would study neutrino-nucleon and neutrino-electron scattering and would be performed at high performance detectors placed as close as is practical to the neutrino production straight section of muon storage rings in order to exploit beams with transverse dimensions as small as a few tens of centimeters.

  11. Development of a Portable Muon Witness System

    SciTech Connect

    Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.

    2011-01-01

    Since understanding and quantifying cosmic ray induced radioactive backgrounds in copper and germanium are important to the MAJORANA DEMONSTRATOR, methods are needed for monitoring the levels of such backgrounds produced in materials being transported and processed for the experiment. This report focuses on work conducted at Pacific Northwest National Laboratory to develop a muon witness system as a one way of monitoring induced activities. The operational goal of this apparatus is to characterize cosmic ray exposure of materials. The cosmic ray flux at the Earth’s surface is composed of several types of particles, including neutrons, muons, gamma rays and protons. These particles induce nuclear reactions, generating isotopes that contribute to the radiological background. Underground, the main mechanism of activation is by muon produced spallation neutrons since the hadron component of cosmic rays is removed at depths greater than a few tens of meters. This is a sub-dominant contributor above ground, but muons become predominant in underground experiments. For low-background experiments cosmogenic production of certain isotopes, such as 68Ge and 60Co, must be accounted for in the background budgets. Muons act as minimum ionizing particles, depositing a fixed amount of energy per unit length in a material, and have a very high penetrating power. Using muon flux measurements as a “witness” for the hadron flux, the cosmogenic induced activity can be quantified by correlating the measured muon flux and known hadronic production rates. A publicly available coincident muon cosmic ray detector design, the Berkeley Lab Cosmic Ray Detector (BLCRD), assembled by Juniata College, is evaluated in this work. The performance of the prototype is characterized by assessing its muon flux measurements. This evaluation is done by comparing data taken in identical scenarios with other cosmic ray telescopes. The prototype is made of two plastic scintillator paddles with

  12. Cosmic muon flux measurements at the Kimballton Underground Research Facility

    NASA Astrophysics Data System (ADS)

    Kalousis, L. N.; Guarnaccia, E.; Link, J. M.; Mariani, C.; Pelkey, R.

    2014-08-01

    In this article, the results from a series of muon flux measurements conducted at the Kimballton Underground Research Facility (KURF), Virginia, United States, are presented. The detector employed for these investigations, is made of plastic scintillator bars readout by wavelength shifting fibers and multianode photomultiplier tubes. Data was taken at several locations inside KURF, spanning rock overburden values from ~ 200 to 1450 m.w.e. From the extracted muon rates an empirical formula was devised, that estimates the muon flux inside the mine as a function of the overburden. The results are in good agreement with muon flux calculations based on analytical models and MUSIC.

  13. Neutron/muon correlation functions to improve neutron detection capabilities outside nuclear facilities

    NASA Astrophysics Data System (ADS)

    Ordinario, Donald Thomas

    The natural neutron background rate is largely due to cosmic ray interactions in the atmosphere and the subsequent neutron emission from the interaction products. The neutron background is part of a larger cosmic radiation shower that also includes electrons, gamma rays, and muons. Since neutrons interact much differently than muons in building materials, the muon and neutron fluence rates in the natural background can be compared to the measured muon and neutron fluence rate when shielded by common building materials. The simultaneous measurement of muon and neutron fluence rates might allow for an earlier identification of man-made neutron sources, such as hidden nuclear materials. This study compares natural background neutron rates to computer simulated neutron rates shielded by common structural and building materials. The characteristic differences between neutrons and muons resulted in different attenuation properties under the same shielded conditions. Correlation functions between cosmic ray generated neutrons and muons are then used to predict neutron fluence rates in different urban environments.

  14. Utilisation de dispositifs a transfert de charge pour la detection de muons cosmiques dans un contexte de tomographie

    NASA Astrophysics Data System (ADS)

    Marion-Ouellet, Laurence Olivier

    775 mum respectively, which translates to 28 000 and 76 000 electron-hole pairs as signal for the two thicknesses. All the results obtained through Geant4 are consistent with the known theory of energy deposits in thin semiconductor materials. A practical experimentation was also considered, using an astronomical camera DMK51 AU02.AS to capture a series of images hidden from light with the camera turned towards the sky. The pixels presenting a high intensity are considered to be the consequence of the passage of a muon. The expected rate of detection according to the size of the detector was 0.372 muons per minute but the results were 0.1578 muons per minute for data taken inside Polytechnique and 0.1615 for images taken outside. Therefore, the presence of about two meters of concrete above the camera does not significantly affect the detectable muon flux. However, the ratio of 40 % between expected signal and the observations is explained by the small size of the sensitive area of a pixel when compared to its total size. Components such as electrodes and differently doped silicon occupy a certain area in the pixel causing it, in the eyes of the muon, to be much smaller. A smaller pixel will ensure a smaller expected muon flux. Also, the possibility that the energy deposition is simply too small in some cases to be detected is also studied in the results section and solutions to resolve this problem are presented in the conclusion.

  15. The Muon Collider

    SciTech Connect

    Zisman, Michael S

    2010-05-17

    We describe the scientific motivation for a new type of accelerator, the muon collider. This accelerator would permit an energy-frontier scientific program and yet would fit on the site of an existing laboratory. Such a device is quite challenging, and requires a substantial R&D program. After describing the ingredients of the facility, the ongoing R&D activities of the Muon Accelerator Program are discussed. A possible U.S. scenario that could lead to a muon collider at Fermilab is briefly mentioned.

  16. The Muon Collider

    SciTech Connect

    Zisman, Michael S.

    2011-01-05

    We describe the scientific motivation for a new type of accelerator, the muon collider. This accelerator would permit an energy-frontier scientific program and yet would fit on the site of an existing laboratory. Such a device is quite challenging, and requires a substantial R&D program. After describing the ingredients of the facility, the ongoing R&D activities of the Muon Accelerator Program are discussed. A possible U.S. scenario that could lead to a muon collider at Fermilab is briefly mentioned.

  17. Muons and neutrinos

    NASA Technical Reports Server (NTRS)

    Stanev, T.

    1986-01-01

    The first generation of large and precise detectors, some initially dedicated to search for nucleon decay has accumulated significant statistics on neutrinos and high-energy muons. A second generation of even better and bigger detectors are already in operation or in advanced construction stage. The present set of experimental data on muon groups and neutrinos is qualitatively better than several years ago and the expectations for the following years are high. Composition studies with underground muon groups, neutrino detection, and expected extraterrestrial neutrino fluxes are discussed.

  18. Real-Time Imaging of Ground Cover: Relationships with Radiation Capture, Canopy Photosynthesis, and Daily Growth Rate

    NASA Technical Reports Server (NTRS)

    Klassen, S. P.; Ritchie, G.; Frantz, J. M.; Pinnock, D.; Bugbee, B.

    2003-01-01

    Cumulative absorbed radiation is highly correlated with crop biomass and yield. In this chapter we describe the use of a digital camera and commercial imaging software for estimating daily radiation capture, canopy photosynthesis, and relative growth rate. Digital images were used to determine percentage of ground cover of lettuce (Lactuca sativa L.) communities grown at five temperatures. Plants were grown in a steady-state, 10-chamber CO2 gas exchange system, which was used to measure canopy photosynthesis and daily carbon gain. Daily measurements of percentage of ground cover were highly correlated with daily measurements of both absorbed radiation (r(sup 2) = 0.99) and daily carbon gain (r(sup 2) = 0.99). Differences among temperature treatments indicated that these relationships were influenced by leaf angle, leaf area index, and chlorophyll content. An analysis of the daily images also provided good estimates of relative growth rates, which were verified by gas exchange measurements of daily carbon gain. In a separate study we found that images taken at hourly intervals were effective for monitoring real-time growth. Our data suggests that hourly images can be used for early detection of plant stress. Applications, limitations, and potential errors are discussed. We have long known that crop yield is determined by the efficiency of four component processes: (i) radiation capture, (ii) quantum yield, (iii) carbon use efficiency, and (iv) carbon partitioning efficiency (Charles-Edwards, 1982; Penning de Vries & van Laar, 1982; Thornley, 1976). More than one-half century ago, Watson (1947, 1952) showed that variation in radiation capture accounted for almost all of the variation in yield between sites in temperate regions, because the three other components are relatively constant when the crop is not severely stressed. More recently, Monteith (1977) reviewed the literature on the close correlation between radiation capture and yield. Bugbee and Monje (1992

  19. Measurement of cosmic-ray muons and muon-induced neutrons in the Aberdeen Tunnel Underground Laboratory

    NASA Astrophysics Data System (ADS)

    Blyth, S. C.; Chan, Y. L.; Chen, X. C.; Chu, M. C.; Cui, K. X.; Hahn, R. L.; Ho, T. H.; Hsiung, Y. B.; Hu, B. Z.; Kwan, K. K.; Kwok, M. W.; Kwok, T.; Lau, Y. P.; Leung, J. K. C.; Leung, K. Y.; Lin, G. L.; Lin, Y. C.; Luk, K. B.; Luk, W. H.; Ngai, H. Y.; Ngan, S. Y.; Pun, C. S. J.; Shih, K.; Tam, Y. H.; Tsang, R. H. M.; Wang, C. H.; Wong, C. M.; Wong, H. L. H.; Wong, K. K.; Yeh, M.; Zhang, B. J.; Aberdeen Tunnel Experiment Collaboration

    2016-04-01

    We have measured the muon flux and production rate of muon-induced neutrons at a depth of 611 m water equivalent. Our apparatus comprises three layers of crossed plastic scintillator hodoscopes for tracking the incident cosmic-ray muons and 760 L of a gadolinium-doped liquid scintillator for producing and detecting neutrons. The vertical muon intensity was measured to be Iμ=(5.7 ±0.6 )×10-6 cm-2 s-1 sr-1 . The yield of muon-induced neutrons in the liquid scintillator was determined to be Yn=(1.19 ±0.08 (stat)±0.21 (syst))×10-4 neutrons /(μ .g .cm-2 ) . A fit to the recently measured neutron yields at different depths gave a mean muon energy dependence of ⟨Eμ⟩ 0.76 ±0.03 for liquid-scintillator targets.

  20. Measurement of cosmic-ray muons and muon-induced neutrons in the Aberdeen Tunnel Underground Laboratory

    DOE PAGES

    Yeh, M.; Chan, Y. L.; Chen, X. C.; ...

    2016-04-07

    In this study, we have measured the muon flux and production rate of muon-induced neutrons at a depth of 611 m water equivalent. Our apparatus comprises three layers of crossed plastic scintillator hodoscopes for tracking the incident cosmic-ray muons and 760 L of a gadolinium-doped liquid scintillator for producing and detecting neutrons. The vertical muon intensity was measured to be Iμ = (5.7±0.6)×10–6 cm–2 s–1 sr–1. The yield of muon-induced neutrons in the liquid scintillator was determined to be Yn = (1.19 ± 0.08(stat) ± 0.21(syst)) × 10–4 neutrons/(μ•g•cm–2). A fit to the recently measured neutron yields at different depthsmore » gave a mean muon energy dependence of < Eμ >0.76±0.03 for liquid-scintillator targets.« less

  1. Monitoring oral temperature, heart rate, and respiration rate of West Indian manatees (Trichechus manatus) during capture and handling in the field

    USGS Publications Warehouse

    Wong, Arthur W.; Bonde, Robert K.; Siegal-Willott, Jessica; Stamper, M. Andrew; Colee, James; Powell, James A.; Reid, James P.; Deutsch, Charles J.; Harr, Kendal E.

    2012-01-01

    West Indian manatees (Trichechus manatus) are captured, handled, and transported to facilitate conservation, research, and rehabilitation efforts. Monitoring manatee oral temperature (OT), heart rate (HR), and respiration rate (RR) during out-of-water handling can assist efforts to maintain animal well-being and improve medical response to evidence of declining health. To determine effects of capture on manatee vital signs, we monitored OT, HR, and RR continuously for a 50-min period in 38 healthy, awake, juvenile and adult Florida manatees (T. m. latirostris) and 48 similar Antillean manatees (T. m. manatus). We examined creatine kinase (CK), potassium (K+), serum amyloid A (SAA), and lactate values for each animal to assess possible systemic inflammation and muscular trauma. OT range was 29.5 to 36.2° C, HR range was 32 to 88 beats/min, and RR range was 0 to 17 breaths/5 min. Antillean manatees had higher initial OT, HR, and RR than Florida manatees (p < 0.001). As monitoring time progressed, mean differences between the subspecies were no longer significant. High RR over monitoring time was associated with high lactate concentration. Antillean manatees had higher overall lactate values ([mean ± SD] 20.6 ± 7.8 mmol/L) than Florida manatees (13.7 ± 6.7 mmol/L; p < 0.001). We recommend monitoring manatee OT, HR, and RR during capture and handling in the field or in a captive care setting.

  2. Increasing capture efficiency of pallid sturgeon Scaphirhynchus albus (Forbes and Richardson, 1905) and the reliability of catch rate estimates

    USGS Publications Warehouse

    DeVries, R. J.; Hann, D. A.; Schramm, H.L.

    2015-01-01

    This study evaluated the effects of environmental parameters on the probability of capturing endangered pallid sturgeon (Scaphirhynchus albus) using trotlines in the lower Mississippi River. Pallid sturgeon were sampled by trotlines year round from 2008 to 2011. A logistic regression model indicated water temperature (T; P < 0.01) and depth (D; P = 0.03) had significant effects on capture probability (Y = −1.75 − 0.06T + 0.10D). Habitat type, surface current velocity, river stage, stage change and non-sturgeon bycatch were not significant predictors (P = 0.26–0.63). Although pallid sturgeon were caught throughout the year, the model predicted that sampling should focus on times when the water temperature is less than 12°C and in deeper water to maximize capture probability; these water temperature conditions commonly occur during November to March in the lower Mississippi River. Further, the significant effect of water temperature which varies widely over time, as well as water depth indicate that any efforts to use the catch rate to infer population trends will require the consideration of temperature and depth in standardized sampling efforts or adjustment of estimates.

  3. Characteristics of neutrons produced by muons in a standard rock

    SciTech Connect

    Malgin, A. S.

    2015-10-15

    Characteristics of cosmogenic neutrons, such as the yield, production rate, and flux, were determined for a standard rock. The dependences of these quantities on the standard-rock depth and on the average muon energy were obtained. These properties and dependences make it possible to estimate easy the muon-induced neutron background in underground laboratories for various chemical compositions of rock.

  4. Reaction rate calibration techniques at ZPPR for /sup 239/Pu fission, /sup 235/U fission, /sup 238/U fission, and /sup 238/U capture

    SciTech Connect

    Brumbach, S.B.; Maddison, D.W.

    1982-06-10

    Reaction-rate calibration techniques used at ZPPR are described for /sup 239/Pu fission, /sup 235/U fission, /sup 238/U fission and /sup 238/U capture. In addition to these absolute reaction rates, calibration techniques are described for fission-rate ratios and the ratio of /sup 238/U capture to /sup 239/U capture to /sup 239/Pu fission. Uncertainty estimates are presented for all calibrations. Intercomparison measurements are reported which support the validity of the calibration techniques and their estimated uncertainties.

  5. Adiabatic capture and debunching

    SciTech Connect

    Ng, K.Y.; /Fermilab

    2012-03-01

    In the study of beam preparation for the g-2 experiment, adiabatic debunching and adiabatic capture are revisited. The voltage programs for these adiabbatic processes are derived and their properties discussed. Comparison is made with some other form of adiabatic capture program. The muon g-2 experiment at Fermilab calls for intense proton bunches for the creation of muons. A booster batch of 84 bunches is injected into the Recycler Ring, where it is debunched and captured into 4 intense bunches with the 2.5-MHz rf. The experiment requires short bunches with total width less than 100 ns. The transport line from the Recycler to the muon-production target has a low momentum aperture of {approx} {+-}22 MeV. Thus each of the 4 intense proton bunches required to have an emittance less than {approx} 3.46 eVs. The incoming booster bunches have total emittance {approx} 8.4 eVs, or each one with an emittance {approx} 0.1 eVs. However, there is always emittance increase when the 84 booster bunches are debunched. There will be even larger emittance increase during adiabatic capture into the buckets of the 2.5-MHz rf. In addition, the incoming booster bunches may have emittances larger than 0.1 eVs. In this article, we will concentrate on the analysis of the adiabatic capture process with the intention of preserving the beam emittance as much as possible. At this moment, beam preparation experiment is being performed at the Main Injector. Since the Main Injector and the Recycler Ring have roughly the same lattice properties, we are referring to adiabatic capture in the Main Injector instead in our discussions.

  6. Detector Background at Muon Colliders

    SciTech Connect

    Mokhov, N.V.; Striganov, S.I.; /Fermilab

    2011-09-01

    Physics goals of a Muon Collider (MC) can only be reached with appropriate design of the ring, interaction region (IR), high-field superconducting magnets, machine-detector interface (MDI) and detector. Results of the most recent realistic simulation studies are presented for a 1.5-TeV MC. It is shown that appropriately designed IR and MDI with sophisticated shielding in the detector have a potential to substantially suppress the background rates in the MC detector. The main characteristics of backgrounds are studied.

  7. Decay of negative muons bound in {sup 27}Al

    SciTech Connect

    Grossheim, A.; Bayes, R.; Faszer, W.; Fujiwara, M. C.; Gill, D. R.; Gumplinger, P.; Henderson, R. S.; Hillairet, A.; Hu, J.; Marshall, G. M.; Mischke, R. E.; Olchanski, K.; Olin, A.; Openshaw, R.; Poutissou, J.-M.; Poutissou, R.; Sheffer, G.; Shin, B.; Bueno, J. F.; Hasinoff, M. D.

    2009-09-01

    We present the first measurement of the energy spectrum up to 70 MeV of electrons from the decay of negative muons after they become bound in {sup 27}Al atoms. The data were taken with the TWIST apparatus at TRIUMF. We find a muon lifetime of (864.6{+-}1.2) ns, in agreement with earlier measurements. The asymmetry of the decay spectrum is consistent with zero, indicating that the atomic capture has completely depolarized the muons. The measured momentum spectrum is in reasonable agreement with theoretical predictions at the higher energies, but differences around the peak of the spectrum indicate the need for O({alpha}) radiative corrections to the calculations. The present measurement is the most precise measurement of the decay spectrum of muons bound to any nucleus.

  8. Fukushima Daiichi Muon Imaging

    NASA Astrophysics Data System (ADS)

    Miyadera, Haruo

    2015-10-01

    Japanese government announced cold-shutdown condition of the reactors at Fukushima Daiichi by the end of 2011, and mid- and long-term roadmap towards decommissioning has been drawn. However, little is known for the conditions of the cores because access to the reactors has been limited by the high radiation environment. The debris removal from the Unit 1 - 3 is planned to start as early as 2020, but the dismantlement is not easy without any realistic information of the damage to the cores, and the locations and amounts of the fuel debris. Soon after the disaster of Fukushima Daiichi, several teams in the US and Japan proposed to apply muon transmission or scattering imagings to provide information of the Fukushima Daiichi reactors without accessing inside the reactor building. GEANT4 modeling studies of Fukushima Daiichi Unit 1 and 2 showed clear superiority of the muon scattering method over conventional transmission method. The scattering method was demonstrated with a research reactor, Toshiba Nuclear Critical Assembly (NCA), where a fuel assembly was imaged with 3-cm resolution. The muon scattering imaging of Fukushima Daiichi was approved as a national project and is aiming at installing muon trackers to Unit 2. A proposed plan includes installation of muon trackers on the 2nd floor (operation floor) of turbine building, and in front of the reactor building. Two 7mx7m detectors were assembled at Toshiba and tested.

  9. Analysis of Near Horizontal Muons at HAWC

    NASA Astrophysics Data System (ADS)

    Barber, Ahron; HAWC Collaboration

    2017-01-01

    The HAWC (High Altitude Water Cherenkov) gamma ray observatory observes muons with nearly horizontal trajectories. HAWC is located at an altitude of 4100 meters a.s.l. on Sierra Negra in Mexico. The Gamma and Cosmic Ray detector is composed of 300 water tanks, 7.3 m in diameter and 4.5 m tall, spread over a physical area of 22,000 m2. Due to its thickness of 4.5 m, HAWC acts as a hodoscope capable of observing muons with trajectories at zenith angles greater than 75 degrees to just over 90 degrees. These muon trajectories have a unique signal in that they are linear and travel at nearly the speed of light. CORSIKA simulations indicate that these muons originate from high zenith angle cosmic ray events, where the air shower core is located at great distance from HAWC. I will present the angular distribution and rate at which HAWC observes these muon events. High Altitude Water Cherenkov Observatory.

  10. Capturing Age-group Differences and Developmental Change with the BASC Parent Rating Scales

    PubMed Central

    Barbot, Baptiste; Hein, Sascha; Luthar, Suniya S.; Grigorenko, Elena L.

    2014-01-01

    Estimation of age-group differences and intra-individual change across distinct developmental periods is often challenged by the use of age-appropriate (but non-parallel) measures. We present a short version of the Behavior Assessment System (Reynolds & Kamphaus, 1998), Parent Rating Scales for Children (PRS-C) and Adolescents (PRS-A), which uses only their common-items to derive estimates of the initial constructs optimized for developmental studies. Measurement invariance of a three-factor model (Externalizing, Internalizing, Adaptive Skills) was tested across age-groups (161 mothers using PRS-C; 200 mothers using PRS-A) and over time (115 mothers using PRS-C at baseline and PRS-A five years later) with the original versus short PRS. Results indicated that the short PRS holds a sufficient level of invariance for a robust estimation of age-group differences and intra-individual change, as compared to the original PRS, which held only weak invariance leading to flawed developmental inferences. Importance of test-content parallelism for developmental studies is discussed. PMID:25045196

  11. Muon Fluence Measurements for Homeland Security Applications

    SciTech Connect

    Ankney, Austin S.; Berguson, Timothy J.; Borgardt, James D.; Kouzes, Richard T.

    2010-08-10

    This report focuses on work conducted at Pacific Northwest National Laboratory to better characterize aspects of backgrounds in RPMs deployed for homeland security purposes. Two polyvinyl toluene scintillators were utilized with supporting NIM electronics to measure the muon coincidence rate. Muon spallation is one mechanism by which background neutrons are produced. The measurements performed concentrated on a broad investigation of the dependence of the muon flux on a) variations in solid angle subtended by the detector; b) the detector inclination with the horizontal; c) depth underground; and d) diurnal effects. These tests were conducted inside at Building 318/133, outdoors at Building 331G, and underground at Building 3425 at Pacific Northwest National Laboratory.

  12. EFFECTS OF TURBULENCE, ECCENTRICITY DAMPING, AND MIGRATION RATE ON THE CAPTURE OF PLANETS INTO MEAN MOTION RESONANCE

    SciTech Connect

    Ketchum, Jacob A.; Adams, Fred C.; Bloch, Anthony M.

    2011-01-01

    Pairs of migrating extrasolar planets often lock into mean motion resonance as they drift inward. This paper studies the convergent migration of giant planets (driven by a circumstellar disk) and determines the probability that they are captured into mean motion resonance. The probability that such planets enter resonance depends on the type of resonance, the migration rate, the eccentricity damping rate, and the amplitude of the turbulent fluctuations. This problem is studied both through direct integrations of the full three-body problem and via semi-analytic model equations. In general, the probability of resonance decreases with increasing migration rate, and with increasing levels of turbulence, but increases with eccentricity damping. Previous work has shown that the distributions of orbital elements (eccentricity and semimajor axis) for observed extrasolar planets can be reproduced by migration models with multiple planets. However, these results depend on resonance locking, and this study shows that entry into-and maintenance of-mean motion resonance depends sensitively on the migration rate, eccentricity damping, and turbulence.

  13. Effects of Biogents Sentinel Trap Field Placement on Capture Rates of Adult Asian Tiger Mosquitoes, Aedes albopictus

    PubMed Central

    Crepeau, Taryn N.; Healy, Sean P.; Bartlett-Healy, Kristen; Unlu, Isik; Farajollahi, Ary; Fonseca, Dina M.

    2013-01-01

    The Biogents® Sentinel (BGS) trap is the standard tool to monitor adult Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae), the Asian tiger mosquito. BGS traps are commonly placed in residential properties during surveillance operations, but locations within properties may have significant differences in ambient light, temperature, and humidity (e.g. between a sunlit lawn and shady underbrush). We examined the effect of BGS trap placement on Ae. albopictus capture rates in three residential properties in Monmouth County, New Jersey, USA. In each property we visually selected locations as shade, partial shade, and sun. Traps in “partial shade” locations were under vegetation and were exposed to filtered sunlight during some parts of the day while “shaded” locations were never exposed to direct sunlight. Locations defined as “sun” were exposed to direct sunlight for large parts of the day. We placed a BGS trap in each of the three location types and used small data loggers to measure temperature, relative humidity, and light exposure at each trap during a 24-hour deployment. To address temporal variability, we made seven separate measurements from 31 August to 22 September 2010. We found that “partial shade” and “full shade” locations did not differ but that “full sun” locations had significantly higher light exposure, higher temperature, and lower humidity. Importantly, Ae. albopictus catches (males, females, or both) were consistently and significantly over 3 times higher in traps located in shaded locations. To further investigate the effects of local temperature and humidity on surveillance we examined Ae. albopictus collections from 37 BGS traps fitted with data loggers and deployed weekly from August through mid October, during the 2009 season, in three urban sites in Mercer County, NJ. We confirmed that local climate influences capture rates and that Ae. albopictus surveillance projects need to monitor trap placement carefully

  14. Muon spin spectroscopy of ferrocene: characterization of muoniated ferrocenyl radicals.

    PubMed

    McKenzie, Iain

    2014-06-14

    Radicals formed by the reaction of muonium (Mu), a light isotope of hydrogen, with ferrocene and ferrocene-d10 have been studied with the avoided level crossing muon spin resonance (ALC-μSR) and longitudinal field muon spin relaxation (LF-μSR) techniques between 10 and 100 K. A single type of radical was observed in each compound and the muon hyperfine coupling constants (hfcc) and the muon spin relaxation rates were measured as a function of temperature. A previous report concerning the observation of Mu adducts of ferrocene (U. A. Jayasooriya et al. Chem. - Eur. J., 2007, 13, 2266-2276) appears to be incorrect. DFT calculations were performed to aid in the assignment of the ALC-μSR spectra. A tentative assignment is that the observed radicals were formed by Mu addition to the exterior of the cyclopentadienyl rings and that the structures are distorted due to interactions with neighbouring molecules. The temperature dependence of the muon hfcc can be explained assuming the population of two levels with different muon hfccs separated by 1.4 ± 0.1 kJ mol(-1). The temperature dependence of the width and amplitude of the Δ1 resonance and the muon spin relaxation rate suggests that the electron spin relaxation rate increase with temperature, but the relaxation mechanism is unknown.

  15. Borehole Muon Detector Development

    NASA Astrophysics Data System (ADS)

    Bonneville, A.; Flygare, J.; Kouzes, R.; Lintereur, A.; Yamaoka, J. A. K.; Varner, G. S.

    2015-12-01

    Increasing atmospheric CO2 concentrations have spurred investigation into carbon sequestration methods. One of the possibilities being considered, storing super-critical CO2 in underground reservoirs, has drawn more attention and pilot projects are being supported worldwide. Monitoring of the post-injection fate of CO2 is of utmost importance. Generally, monitoring options are active methods, such as 4D seismic reflection or pressure measurements in monitoring wells. We propose here to develop a 4-D density tomography of subsurface CO2 reservoirs using cosmic-ray muon detectors deployed in a borehole. Muon detection is a relatively mature field of particle physics and there are many muon detector designs, though most are quite large and not designed for subsurface measurements. The primary technical challenge preventing deployment of this technology in the subsurface is the lack of miniaturized muon-tracking detectors capable of fitting in standard boreholes and that will resist the harsh underground conditions. A detector with these capabilities is being developed by a collaboration supported by the U.S. Department of Energy. Current simulations based on a Monte Carlo modeling code predict that the incoming muon angle can be resolved with an error of approximately two degrees, using either underground or sea level spectra. The robustness of the design comes primarily from the use of scintillating rods as opposed to drift tubes. The rods are arrayed in alternating layers to provide a coordinate scheme. Preliminary testing and measurements are currently being performed to test and enhance the performance of the scintillating rods, in both a laboratory and a shallow underground facility. The simulation predictions and data from the experiments will be presented.

  16. Radioactive decay speedup at T=5 K: electron-capture decay rate of (7)Be encapsulated in C(60).

    PubMed

    Ohtsuki, T; Ohno, K; Morisato, T; Mitsugashira, T; Hirose, K; Yuki, H; Kasagi, J

    2007-06-22

    The electron-capture (EC) decay rate of (7)Be in C(60) at the temperature of liquid helium (T=5 K) was measured and compared with the rate in Be metal at T=293 K. We found that the half-life of (7)Be in endohedral C(60) ((7)Be@C(60)) at a temperature close to T=5 K is 52.47+/-0.04 d, a value that is 0.34% faster than that at T=293 K. In this environment, the half-life of (7)Be is nearly 1.5% faster than that inside Be metal at room temperature (T=293 K). We then interpreted our observations in terms of calculations of the electron density at the (7)Be nucleus position inside the C(60); further, we estimate theoretically the temperature dependence (at T=0 K and 293 K) of the electron density at the Be nucleus position in the stable center inside C(60). The theoretical estimates were almost in agreement with the experimental observations.

  17. Discriminating the drivers of edge effects on nest predation: forest edges reduce capture rates of ship rats (Rattus rattus), a globally invasive nest predator, by altering vegetation structure.

    PubMed

    Ruffell, Jay; Didham, Raphael K; Barrett, Paul; Gorman, Nic; Pike, Rhonda; Hickey-Elliott, Andrée; Sievwright, Karin; Armstrong, Doug P

    2014-01-01

    Forest edges can strongly affect avian nest success by altering nest predation rates, but this relationship is inconsistent and context dependent. There is a need for researchers to improve the predictability of edge effects on nest predation rates by examining the mechanisms driving their occurrence and variability. In this study, we examined how the capture rates of ship rats, an invasive nest predator responsible for avian declines globally, varied with distance from the forest edge within forest fragments in a pastoral landscape in New Zealand. We hypothesised that forest edges would affect capture rates by altering vegetation structure within fragments, and that the strength of edge effects would depend on whether fragments were grazed by livestock. We measured vegetation structure and rat capture rates at 488 locations ranging from 0-212 m from the forest edge in 15 forest fragments, seven of which were grazed. Contrary to the vast majority of previous studies of edge effects on nest predation, ship rat capture rates increased with increasing distance from the forest edge. For grazed fragments, capture rates were estimated to be 78% lower at the forest edge than 118 m into the forest interior (the farthest distance for grazed fragments). This relationship was similar for ungrazed fragments, with capture rates estimated to be 51% lower at the forest edge than 118 m into the forest interior. A subsequent path analysis suggested that these 'reverse' edge effects were largely or entirely mediated by changes in vegetation structure, implying that edge effects on ship rats can be predicted from the response of vegetation structure to forest edges. We suggest the occurrence, strength, and direction of edge effects on nest predation rates may depend on edge-driven changes in local habitat when the dominant predator is primarily restricted to forest patches.

  18. Muon background studies for shallow depth Double - Chooz near detector

    SciTech Connect

    Gómez, H.

    2015-08-17

    Muon events are one of the main concerns regarding background in neutrino experiments. The placement of experimental set-ups in deep underground facilities reduce considerably their impact on the research of the expected signals. But in the cases where the detector is installed on surface or at shallow depth, muon flux remains high, being necessary their precise identification for further rejection. Total flux, mean energy or angular distributions are some of the parameters that can help to characterize the muons. Empirically, the muon rate can be measured in an experiment by a number of methods. Nevertheless, the capability to determine the muons angular distribution strongly depends on the detector features, while the measurement of the muon energy is quite difficult. Also considering that on-site measurements can not be extrapolated to other sites due to the difference on the overburden and its profile, it is necessary to find an adequate solution to perform the muon characterization. The method described in this work to obtain the main features of the muons reaching the experimental set-up, is based on the muon transport simulation by the MUSIC software, combined with a dedicated sampling algorithm for shallow depth installations based on a modified Gaisser parametrization. This method provides all the required information about the muons for any shallow depth installation if the corresponding overburden profile is implemented. In this work, the method has been applied for the recently commissioned Double - Chooz near detector, which will allow the cross-check between the simulation and the experimental data, as it has been done for the far detector.

  19. Precision measurements of fundamental muon properties

    NASA Astrophysics Data System (ADS)

    Debevec, P. T.

    2003-02-01

    The g-factor of the muon differs from two due to the excitation of virtual field quanta and particles. The deviation from two, the g-factor anomaly, can be calculated with high precision in the Standard Model of particle physics. The g-factor anomaly can be measured with high precision by determining the rate at which the spin direction of high-energy muons circulating in a storage ring precesses. The Brookhaven National Laboratory g-2 experiment (BNL g-2 collaboration) has measured g-2 to 1.3 ppm. The result is essentially in agreement with the Standard Model. The result puts interesting constraints on Standard Model extensions. Data under analysis will reduce the uncertainty to the order of 0.5 ppm. The precision timing techniques used in the g-2 experiment are a central element of a new experiment to measure the lifetime of the positive muon. The goal of this experiment is to determine the lifetime to 1 ppm, and the Fermi coupling constant to 0.5 ppm. The high statistics demand of this measurement is satisfied by one of the surface muon beams of the Paul Scherrer Institute. An artificial time structure is imposed on the continuous beam by an electrostatic kicker. The decay positrons are detected in a 180 element quasi-spherical detector. The effective counting rate is of the order of 1 MHz. The experiment is designed to control systematic errors to a level below 1 ppm.

  20. Six Dimensional Bunch Merging for Muon Collider Cooling

    SciTech Connect

    Palmer, R.B.; Fernow, R.C.

    2011-03-28

    A muon collider requires single, intense, muon bunches with small emittances in all six dimensions. It is most efficient to initally phase-rotate the muons into many separate bunches, cool these bunches in six dimensions (6D), and, when cool enough, merge them into single bunches (one of each sign). Previous studies only merged in longitudinal phase space (2D). In this paper we describe merging in all six dimensions (6D). The scheme uses rf for longitudinal merging, and kickers and transports with differing lengths (trombones) for transverse merging. Preliminary simulations, including incorporation in 6D cooling, is described. Muons are efficiently generated by pion decay, but they then have very large emittances. A muon collider requires low emittances, which can be achieved using transverse ionization cooling, combined with emittance exchange using dispersion and shaped absorbers. For efficient capture, muons are first phase-rotated by rf into a train of many bunches. But for high luminosity, we need just one bunch of each sign, so after some initial cooling, these bunches should be merged.

  1. Muon spin rotation research program

    NASA Technical Reports Server (NTRS)

    Stronach, C. E.

    1980-01-01

    Data from cyclotron experiments and room temperature studies of dilute iron alloys and iron crystals under strain were analyzed. The Fe(Mo) data indicate that the effect upon the contact hyperfine field in Fe due to the introduction of Mo is considerably less than that expected from pure dilution, and the muon (+) are attracted to the Mo impurity sites. There is a significant change in the interstitial magnetic field with Nb concentration. The Fe(Ti) data, for which precession could clearly be observed early only at 468K and above, show that the Ti impurities are attractive to muon (+), and the magnitude of B(hf) is reduced far beyond the amount expected from pure dilution. Changes in the intersitital magnetic field with the introduction of Cr, W, Ge, and Si are also discussed. When strained to the elastic limit, the interstitial magnetic field in Fe crystals is reduced by 33 gauss, and the relaxation rate of the precession signal increases by 47%.

  2. Feasibility of using backscattered muons for archeological imaging

    NASA Astrophysics Data System (ADS)

    Bonal, N.; Preston, L. A.

    2013-12-01

    Use of nondestructive methods to accurately locate and characterize underground objects such as rooms and tools found at archeological sites is ideal to preserve these historic sites. High-energy cosmic ray muons are very sensitive to density variation and have been used to image volcanoes and archeological sites such as the Egyptian and Mayan pyramids. Muons are subatomic particles produced in the upper atmosphere that penetrate the earth's crust up to few kilometers. Their absorption rate depends on the density of the materials through which they pass. Measurements of muon flux rate at differing directions provide density variations of the materials between the muon source (cosmic rays and neutrino interactions) and the detector, much like a CAT scan. Currently, muon tomography can resolve features to the sub-meter scale making it useful for this type of work. However, the muon detector must be placed below the target of interest. For imaging volcanoes, the upper portion is imaged when the detector is placed on the earth's surface at the volcano's base. For sites of interest beneath the ground surface, the muon detector would need to be placed below the site in a tunnel or borehole. Placing the detector underground can be costly and may disturb the historical site. We will assess the feasibility of imaging the subsurface using upward traveling muons, to eliminate the current constraint of positioning the detector below the target. This work consists of three parts 1) determine the backscattered flux rate from theory, 2) distinguish backscattered from forward scattered muons at the detector, and 3) validate the theoretical results with field experimentation. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  3. The effects of ultra-strong magnetic fields on electron capture rates for iron group nuclei in the outer crust of magnetars

    NASA Astrophysics Data System (ADS)

    Du, Jun; Luo, Zhi-Quan; Zhang, Jie

    2014-06-01

    Based on the work of Wang et al. (Chin. Phys. Lett. 29:049701, 2012), we re-investigated electron capture on iron group nuclei in the outer crust of magnetars and studied magnetar evolution. Effects of ultra-strong magnetic field on electron capture rates for 57Co have been analyzed in the nuclear shell model and under the Landau-level-quantization approximation, and the electron capture rates and the neutrino energy loss rates on iron group nuclei in the outer crust of magnetar have been calculated. The results show that electron capture rates on 57Co are increase greatly in the ultra-strong magnetic field, and above 3 orders of magnitude generally; and the neutrino energy loss rates by electron capture on iron group nuclei increase above 3 orders of magnitude in the range from B=4.414×1013 G to B=4.414×1015 G. These conclusions play an important role in future studying the evolution of magnetar. Furthermore, we modify the expressions of the electron chemical potential (Fermi energy) and phase space factor by introducing Dirac δ-function, and select appropriate parameters of temperature T, magnetic field B and matter density ρ in the our crust, thus our results will be reliable than those of Wang et al.

  4. High energy muon induced radioactive nuclides in nickel plate and its use for 2-D muon-beam image profile

    NASA Astrophysics Data System (ADS)

    Kurebayashi, Y.; Sakurai, H.; Takahashi, Y.; Doshita, N.; Kikuchi, S.; Tokanai, F.; Horiuchi, K.; Tajima, Y.; Oe, T.; Sato, T.; Gunji, S.; Inui, E.; Kondo, K.; Iwata, N.; Sasaki, N.; Matsuzaki, H.; Kunieda, S.

    2015-11-01

    Target materials were exposed to a muon beam with an energy of 160 GeV/c at the COMPASS experiment line in CERN-SPS to measure the production cross-sections for muon-induced radionuclides. A muon imager containing four nickel plates, each measuring 100 mm×100 mm, exposed to the IP plate successfully detected the muon beam image during an irradiation period of 33 days. The contrasting density rate of the nickel plate was (5.2±0.7)×10-9 PSL/muon per one-day exposure to IP. The image measured 122 mm and 174 mm in horizontal and vertical lengths, respectively, in relation to the surface of the base, indicating that 50±6% of the muon beam flux is confined to an area of 18% of the whole muon beam. The number of muons estimated from the PSL value in the total beam image area (0.81±0.1)×1013 was comparable to the total muon counts of the ion-chamber at the M2 beam line in the CERN-SPS. The production cross-sections of Cr-51, Mn-54, Co-56, Co-57, and Co-58 in nickel were 0.19±0.08, 0.34±0.06, 0.5±0.05, 3.44±0.07, 0.4±0.03 in the unit of mb, respectively, reducing muon associated particles effects. They are approximately 10 times smaller than that a proceeding study by Heisinger et al.

  5. On muon energy spectrum in muon groups underground

    NASA Technical Reports Server (NTRS)

    Bakatanov, V. N.; Chudakov, A. E.; Novoseltsev, Y. F.; Novoseltseva, M. V.; Stenkin, Y. V.

    1985-01-01

    A method is described which was used to measure muon energy spectrum characteristics in muon groups underground using mu-e decays recording. The Baksan Telescope's experimental data on mu-e decays intensity in muon groups of various multiplicities are analyzed. The experimental data indicating very flat spectrum does not however represent the total spectrum in muon groups. Obviously the muon energy spectrum depends strongly on a distance from the group axis. The core attraction effect makes a significant distortion, making the spectrum flatter. After taking this into account and making corrections for this effect the integral total spectrum index in groups has a very small depencence on muon multiplicity and agrees well with expected one: beta=beta (sub expected) = 1.75.

  6. The MICE Muon Beam on ISIS and the beam-line instrumentation of the Muon Ionization Cooling Experiment

    SciTech Connect

    Bogomilov, M.; et al.

    2012-05-01

    The international Muon Ionization Cooling Experiment (MICE), which is under construction at the Rutherford Appleton Laboratory (RAL), will demonstrate the principle of ionization cooling as a technique for the reduction of the phase-space volume occupied by a muon beam. Ionization cooling channels are required for the Neutrino Factory and the Muon Collider. MICE will evaluate in detail the performance of a single lattice cell of the Feasibility Study 2 cooling channel. The MICE Muon Beam has been constructed at the ISIS synchrotron at RAL, and in MICE Step I, it has been characterized using the MICE beam-instrumentation system. In this paper, the MICE Muon Beam and beam-line instrumentation are described. The muon rate is presented as a function of the beam loss generated by the MICE target dipping into the ISIS proton beam. For a 1 V signal from the ISIS beam-loss monitors downstream of our target we obtain a 30 KHz instantaneous muon rate, with a neglible pion contamination in the beam.

  7. Wobbly strings: calculating the capture rate of a webcam using the rolling shutter effect in a guitar

    NASA Astrophysics Data System (ADS)

    Cunnah, David

    2014-07-01

    In this paper I propose a method of calculating the time between line captures in a standard complementary metal-oxide-semiconductor (CMOS) webcam using the rolling shutter effect when filming a guitar. The exercise links the concepts of wavelength and frequency, while outlining the basic operation of a CMOS camera through vertical line capture.

  8. Wobbly Strings: Calculating the Capture Rate of a Webcam Using the Rolling Shutter Effect in a Guitar

    ERIC Educational Resources Information Center

    Cunnah, David

    2014-01-01

    In this paper I propose a method of calculating the time between line captures in a standard complementary metal-oxide-semiconductor (CMOS) webcam using the rolling shutter effect when filming a guitar. The exercise links the concepts of wavelength and frequency, while outlining the basic operation of a CMOS camera through vertical line capture.

  9. Time Modulation of the K-Shell Electron Capture Decay Rates of H-like Heavy Ions at GSI Experiments

    SciTech Connect

    Ivanov, A. N.; Kienle, P.

    2009-08-07

    According to experimental data at GSI, the rates of the number of daughter ions, produced by the nuclear K shell electron capture decays of the H-like heavy ions with one electron in the K shell, such as {sup 140}Pr{sup 58+}, {sup 142}Pm{sup 60+}, and {sup 122}I{sup 52+}, are modulated in time with periods T{sub EC} of the order of a few seconds, obeying an A scaling T{sub EC}=A/20 s, where A is the mass number of the mother nuclei, and with amplitudes a{sub d}{sup EC}approx0.21. We show that these data can be explained in terms of the interference of two massive neutrino mass eigenstates. The appearance of the interference term is due to overlap of massive neutrino mass eigenstate energies and of the wave functions of the daughter ions in two-body decay channels, caused by the energy and momentum uncertainties introduced by time differential detection of the daughter ions in GSI experiments.

  10. Collision rates for rare cell capture in periodic obstacle arrays strongly depend on density of cell suspension.

    PubMed

    Cimrák, I

    2016-11-01

    Recently, computational modelling has been successfully used for determination of collision rates for rare cell capture in periodic obstacle arrays. The models were based on particle advection simulations where the cells were advected according to velocity field computed from two dimensional Navier-Stokes equations. This approach may be used under the assumption of very dilute cell suspensions where no mutual cell collisions occur. We use the object-in-fluid framework to demonstrate that even with low cell-to-fluid ratio, the optimal geometry of the obstacle array significantly changes. We show computational simulations for ratios of 3.5, 6.9 and 10.4% determining the optimal geometry of the periodic obstacle arrays. It was already previously demonstrated that cells in periodic obstacle arrays follow trajectories in two modes: the colliding mode and the zig-zag mode. The colliding mode maximizes the cell-obstacle collision frequency. Our simulations reveal that for dilute suspensions and for suspensions with cell-to-fluid ratio 3.5%, there is a range of column shifts for which the cells follow colliding trajectories. However we showed, that for 6.9 and 10.4%, the cells never follow colliding trajectories.

  11. Muon identification with Muon Telescope Detector at the STAR experiment

    SciTech Connect

    Huang, T. C.; Ma, R.; Huang, B.; Huang, X.; Ruan, L.; Todoroki, T.; Xu, Z.; Yang, C.; Yang, S.; Yang, Q.; Yang, Y.; Zha, W.

    2016-07-15

    The Muon Telescope Detector (MTD) is a newly installed detector in the STAR experiment. It provides an excellent opportunity to study heavy quarkonium physics using the dimuon channel in heavy ion collisions. In this paper, we report the muon identification performance for the MTD using proton-proton collisions at $\\sqrt{s}$ = 500 GeV with various methods. Here, the result using the Likelihood Ratio method shows that the muon identification efficiency can reach up to ~ 90% for muons with transverse momenta greater than 3 GeV/c and the significance of the J/ψ signal is improved by a factor of 2 compared to using the basic selection.

  12. Muon identification with Muon Telescope Detector at the STAR experiment

    NASA Astrophysics Data System (ADS)

    Huang, T. C.; Ma, R.; Huang, B.; Huang, X.; Ruan, L.; Todoroki, T.; Xu, Z.; Yang, C.; Yang, S.; Yang, Q.; Yang, Y.; Zha, W.

    2016-10-01

    The Muon Telescope Detector (MTD) is a newly installed detector in the STAR experiment. It provides an excellent opportunity to study heavy quarkonium physics using the dimuon channel in heavy ion collisions. In this paper, we report the muon identification performance for the MTD using proton-proton collisions at √{ s }=500 GeV with various methods. The result using the Likelihood Ratio method shows that the muon identification efficiency can reach up to ∼90% for muons with transverse momenta greater than 3 GeV/c and the significance of the J / ψ signal is improved by a factor of 2 compared to using the basic selection.

  13. Muon Production Height from the Muon Tracking Detector in KASCADE

    NASA Astrophysics Data System (ADS)

    Büttner, C.; Antoni, T.; Apel, W. D.; Badea, F.; Bekk, K.; Bercuci, A.; Blümer, H.; Bozdog, H.; Brancus, I. M.; Chilingarian, A.; Daumiller, K.; Doll, P.; Engel, R.; Engler, J.; Feßler, F.; Gils, H. J.; Glasstetter, R.; Haungs, A.; Heck, D.; Hörandel, J. R.; Iwan, A.; Kampert, K-H.; Klages, H. O.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Müller, M.; Obenland, R.; Oehschläger, J.; Ostapchenko, S.; Petcu, M.; Rebel, H.; Risse, M.; Roth, M.; Schatz, G.; Schieler, H.; Scholz, J.; Thouw, T.; Ulrich, H.; van Buren, J.; Vardanyan, A.; Weindl, A.; Wochele, J.; Zabierowski, J.

    2003-07-01

    The Muon Tracking Detector (MTD; Eµh =0.8 GeV) [5] of the KASCADEt Grande experiment enables the analysis of the longitudinal shower development by means of the Muon production Height (MPH). The analysis employes radial and tangential angles of the muon track with respect to the shower direction, and the distance of the muon hit to the shower core. Comparing analysed MPH of distributions with Monte Carlo simulations (CORSIKA) [6] an increase of ln A d f the primary cosmic rays with lg(Nµr ) is observed. t

  14. Observation of seasonal variation of atmospheric multiple-muon events in the MINOS near and far detectors

    SciTech Connect

    Adamson, P.

    2015-06-09

    We report the first observation of seasonal modulations in the rates of cosmic ray multiple-muon events at two underground sites, the MINOS Near Detector with an overburden of 225 mwe, and the MINOS Far Detector site at 2100 mwe. Thus, at the deeper site, multiple-muon events with muons separated by more than 8 m exhibit a seasonal rate that peaks during the summer, similar to that of single-muon events. In contrast and unexpectedly, the rate of multiple-muon events with muons separated by less than 5–8 m, and the rate of multiple-muon events in the smaller, shallower Near Detector, exhibit a seasonal rate modulation that peaks in the winter.

  15. Observation of seasonal variation of atmospheric multiple-muon events in the MINOS Near and Far Detectors

    SciTech Connect

    Adamson, P.; Bishai, M.; Diwan, M. V.; Isvan, Z.; Ling, J.; Viren, B.

    2015-06-09

    We report the first observation of seasonal modulations in the rates of cosmic ray multiple-muon events at two underground sites, the MINOS Near Detector with an overburden of 225 mwe, and the MINOS Far Detector site at 2100 mwe. At the deeper site, multiple-muon events with muons separated by more than 8 m exhibit a seasonal rate that peaks during the summer, similar to that of single-muon events. Conversely, the rate of multiple-muon events with muons separated by less than 5–8 m, and the rate of multiple-muon events in the smaller, shallower Near Detector, exhibit a seasonal rate modulation that peaks in the winter.

  16. Observation of seasonal variation of atmospheric multiple-muon events in the MINOS Near and Far Detectors

    DOE PAGES

    Adamson, P.; Bishai, M.; Diwan, M. V.; ...

    2015-06-09

    We report the first observation of seasonal modulations in the rates of cosmic ray multiple-muon events at two underground sites, the MINOS Near Detector with an overburden of 225 mwe, and the MINOS Far Detector site at 2100 mwe. At the deeper site, multiple-muon events with muons separated by more than 8 m exhibit a seasonal rate that peaks during the summer, similar to that of single-muon events. Conversely, the rate of multiple-muon events with muons separated by less than 5–8 m, and the rate of multiple-muon events in the smaller, shallower Near Detector, exhibit a seasonal rate modulation thatmore » peaks in the winter.« less

  17. Muon Collider Machine-Detector Interface

    SciTech Connect

    Mokhov, Nikolai V.; /Fermilab

    2011-08-01

    In order to realize the high physics potential of a Muon Collider (MC) a high luminosity of {mu}{sup +}{mu}{sup -}-collisions at the Interaction Point (IP) in the TeV range must be achieved ({approx}10{sup 34} cm{sup -2}s{sup -1}). To reach this goal, a number of demanding requirements on the collider optics and the IR hardware - arising from the short muon lifetime and from relatively large values of the transverse emittance and momentum spread in muon beams that can realistically be obtained with ionization cooling should be satisfied. These requirements are aggravated by limitations on the quadrupole gradients as well as by the necessity to protect superconducting magnets and collider detectors from muon decay products. The overall detector performance in this domain is strongly dependent on the background particle rates in various sub-detectors. The deleterious effects of the background and radiation environment produced by the beam in the ring are very important issues in the Interaction Region (IR), detector and Machine-Detector Interface (MDI) designs. This report is based on studies presented very recently.

  18. Cosmic ray muons for spent nuclear fuel monitoring

    NASA Astrophysics Data System (ADS)

    Chatzidakis, Stylianos

    There is a steady increase in the volume of spent nuclear fuel stored on-site (at reactor) as currently there is no permanent disposal option. No alternative disposal path is available and storage of spent nuclear fuel in dry storage containers is anticipated for the near future. In this dissertation, a capability to monitor spent nuclear fuel stored within dry casks using cosmic ray muons is developed. The motivation stems from the need to investigate whether the stored content agrees with facility declarations to allow proliferation detection and international treaty verification. Cosmic ray muons are charged particles generated naturally in the atmosphere from high energy cosmic rays. Using muons for proliferation detection and international treaty verification of spent nuclear fuel is a novel approach to nuclear security that presents significant advantages. Among others, muons have the ability to penetrate high density materials, are freely available, no radiological sources are required and consequently there is a total absence of any artificial radiological dose. A methodology is developed to demonstrate the applicability of muons for nuclear nonproliferation monitoring of spent nuclear fuel dry casks. Purpose is to use muons to differentiate between spent nuclear fuel dry casks with different amount of loading, not feasible with any other technique. Muon scattering and transmission are used to perform monitoring and imaging of the stored contents of dry casks loaded with spent nuclear fuel. It is shown that one missing fuel assembly can be distinguished from a fully loaded cask with a small overlapping between the scattering distributions with 300,000 muons or more. A Bayesian monitoring algorithm was derived to allow differentiation of a fully loaded dry cask from one with a fuel assembly missing in the order of minutes and negligible error rate. Muon scattering and transmission simulations are used to reconstruct the stored contents of sealed dry casks

  19. I. Atomic Effects in Tritium Beta-Decay II. Muon to Electron Conversion in Atoms.

    NASA Astrophysics Data System (ADS)

    Wampler, Kevin Dean

    I. The final-state, atomic effects in the low energy end of the tritium beta decay spectrum are studied in detail. I treat the instantaneous, two-electron repulsion in the final state, effectively to all orders in perturbation theory, by solving the eigenvalue problem with a discretized and truncated form of the Hamiltonian. I find that these effects fail to explain the distortion in the spectrum observed by Simpson (Phys. Rev. Lett. 54, 649 (1985)). Simpson attributed this distortion to the admixture of a heavy mass antineutrino in the outgoing electron antineutrino state. In fact, the final-state Coulomb effects enhance the distortion. This calculation clears up some of the ambiguities of other theoretical analyses based on considerations of screening functions and perturbation theory. II. I present a phenomenological study of separate lepton number violating muon to electron conversion in atoms. Previous work on this process has concentrated on elastic transitions where the nucleus remains in the ground state. I present an analysis of the branching ratios of inelastic to elastic transitions. This analysis uses realistic muon wavefunctions and electron plane waves. A multipole analysis is used for the nuclear matrix elements. The particular case of ^{32}S is studied in detail. It is found that, if anomalous muon capture occurs, the coherent (ground-state to ground-state) transition dominates the rate, if this transition is allowed by the coupling constants. However, incoherent (excited state) transitions could be significant in some cases, particularly if coupling to the nuclear pseudo-scalar current occurs, and would permit one to obtain stringent limits on the corresponding couplings that mediate muon number violation.

  20. Muon-catalyzed fusion experiments at LAMPF

    SciTech Connect

    Caffrey, A.J.; Anderson, A.N.; Van Siclen, C.D.W.; Watts, K.D.; Bradbury, J.N.; Gram, P.A.M.; Leon, M.; Maltrud, H.R.; Paciotti, M.A.; Jones, S.E.

    1986-01-01

    Our collaboration has conducted a series of muon-catalysis experiments over broad temperature and density ranges at the LAMPF accelerator in Los Alamos. We have discovered surprising effects on the normalized muon-catalysis cycling rate, lambda/sub c/, and the apparent alpha-particle sticking coefficient, ..omega../sub s/, that depend on the d-t mixture density. This paper reviews our experimental approach, analysis methods, and results for tests with targets varying in density from 0.12 to 1.30, normalized to liquid hydrogen density, and in temperature from 15K to 800K. In particular, results will be presented on the cycling rate, sticking coefficient, and /sup 3/He scavenging rate, as functions of temperature, mixture density, or tritium concentration.

  1. ELECTRON-CAPTURE AND β-DECAY RATES FOR sd-SHELL NUCLEI IN STELLAR ENVIRONMENTS RELEVANT TO HIGH-DENSITY O–NE–MG CORES

    SciTech Connect

    Suzuki, Toshio; Toki, Hiroshi; Nomoto, Ken’ichi

    2016-02-01

    Electron-capture and β-decay rates for nuclear pairs in the sd-shell are evaluated at high densities and high temperatures relevant to the final evolution of electron-degenerate O–Ne–Mg cores of stars with initial masses of 8–10 M{sub ⊙}. Electron capture induces a rapid contraction of the electron-degenerate O–Ne–Mg core. The outcome of rapid contraction depends on the evolutionary changes in the central density and temperature, which are determined by the competing processes of contraction, cooling, and heating. The fate of the stars is determined by these competitions, whether they end up with electron-capture supernovae or Fe core-collapse supernovae. Since the competing processes are induced by electron capture and β-decay, the accurate weak rates are crucially important. The rates are obtained for pairs with A = 20, 23, 24, 25, and 27 by shell-model calculations in the sd-shell with the USDB Hamiltonian. Effects of Coulomb corrections on the rates are evaluated. The rates for pairs with A = 23 and 25 are important for nuclear Urca processes that determine the cooling rate of the O–Ne–Mg core, while those for pairs with A = 20 and 24 are important for the core contraction and heat generation rates in the core. We provide these nuclear rates at stellar environments in tables with fine enough meshes at various densities and temperatures for studies of astrophysical processes sensitive to the rates. In particular, the accurate rate tables are crucially important for the final fates of not only O–Ne–Mg cores but also a wider range of stars, such as C–O cores of lower-mass stars.

  2. Limits on a muon flux from neutralino annihilations in the Sun with the IceCube 22-string detector

    SciTech Connect

    IceCube Collaboration; Klein, Spencer

    2009-04-28

    A search for muon neutrinos from neutralino annihilations in the Sun has been performed with the IceCube 22-string neutrino detector using data collected in 104.3 days of live-time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured neutralinos in the Sun and converted to limits on the WIMP-proton cross-sections for WIMP masses in the range 250-5000 GeV. These results are the most stringent limits to date on neutralino annihilation in the Sun.

  3. PHENIX Muon Tracking Detector Gas System

    NASA Astrophysics Data System (ADS)

    Kotchenda, L.; Kravtsov, P.; Pisani, R. P.; Tretiakov, G.; Trofimov, V.

    2007-07-01

    The Muon Tracking Detector Gas System was designed and fabricated to supply Ar+30% CO 2+20% CF 4 mixture to the PHENIX [K. Adcox, S.S. Adler, M. Aizam, et al., Nucl. Instr. and Meth. A 499 (2003) 669.] [1]. Muon Tracking (MuTr) chambers located at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven Nation Lab (BNL). The gas system purpose is to provide gas at the requested mixture at a constant controlled pressure and at various flow rates. The system can do this while monitoring the mixture's temperature, pressure, flow rate, and CO 2, oxygen, and moisture content. A custom computer data acquisition system collects and logs the gas system operating parameters. This system can also be alarmed to provide automatic responses to undesired system conditions.

  4. Electron-Muon Ranger: Performance in the MICE muon beam

    SciTech Connect

    Adams, D.

    2015-12-16

    The Muon Ionization Cooling Experiment (MICE) will perform a detailed study of ionization cooling to evaluate the feasibility of the technique. To carry out this program, MICE requires an efficient particle-identification (PID) system to identify muons. The Electron-Muon Ranger (EMR) is a fully-active tracking-calorimeter that forms part of the PID system and tags muons that traverse the cooling channel without decaying. The detector is capable of identifying electrons with an efficiency of 98.6%, providing a purity for the MICE beam that exceeds 99.8%. Lastly, the EMR also proved to be a powerful tool for the reconstruction of muon momenta in the range 100–280 MeV/c.

  5. Electron-Muon Ranger: Performance in the MICE muon beam

    DOE PAGES

    Adams, D.

    2015-12-16

    The Muon Ionization Cooling Experiment (MICE) will perform a detailed study of ionization cooling to evaluate the feasibility of the technique. To carry out this program, MICE requires an efficient particle-identification (PID) system to identify muons. The Electron-Muon Ranger (EMR) is a fully-active tracking-calorimeter that forms part of the PID system and tags muons that traverse the cooling channel without decaying. The detector is capable of identifying electrons with an efficiency of 98.6%, providing a purity for the MICE beam that exceeds 99.8%. Lastly, the EMR also proved to be a powerful tool for the reconstruction of muon momenta inmore » the range 100–280 MeV/c.« less

  6. Compact Muon Production and Collection Scheme for High-Energy Physics Experiments

    SciTech Connect

    Stratakis, Diktys; Neuffer, David V.

    2014-11-10

    The relative immunity of muons to synchrotron radiation suggests that they might be used in place of electrons as probes in fundamental high-energy physics experiments. Muons are commonly produced indirectly through pion decay by interaction of a charged particle beam with a target. However, the large angle and energy dispersion of the initial beams as well as the short muon lifetime limits many potential applications. Here, we describe a fast method for manipulating the longitudinal and transverse phase-space of a divergent pion-muon beam to enable efficient capture and downstream transport with minimum losses. We also discuss the design of a handling system for the removal of unwanted secondary particles from the target region and thus reduce activation of the machine. The compact muon source we describe can be used for fundamental physics research in neutrino experiments.

  7. Ionization Cooling for Muon Experiments

    SciTech Connect

    Alexahin, Y.; Neuffer, D.; Prebys, E.

    2014-09-18

    Possible application for muon experiments such as mu2e is discussed of the initial part of the ionization cooling channel originally developed for muon collider. It is shown that with the FNAL Booster as the proton driver the mu2e sensitivity can be increased by two orders of magnitude compared to the presently considered experiment.

  8. The influence of hook type, angler experience, and fish size on injury rates and the duration of capture in an Alaskan catch-and-release rainbow trout fishery

    USGS Publications Warehouse

    Meka, Julie M.

    2004-01-01

    Owing to concerns about the high incidence of past hooking injuries in Alagnak River rainbow trout Oncorhynchus mykiss, fish were captured with spin- and fly-fishing gear with barbed and barbless circle and "J" hooks to determine gear types contributing to injury. Landing and hook removal times were measured for a portion of fish captured, and the anatomical hooking location, hooking scar locations, bleeding intensity, angler experience, and fish size were recorded for all captured fish. Approximately 62% of fish captured experienced at least one new hooking injury, and 29% of fish had at least one past hooking injury. Small fish sustained higher new injury and bleeding rates, but large fish had higher past injury rates. Injury rates were higher for barbed J hooks, barbed J hooks took longer to remove, and fish caught by spin-fishing were injured more frequently than fish caught by fly-fishing. Fewer fly-fishing-caught fish were injured using circle hooks, and circle hooks tended to hook fish in only one location, generally in the jaw. Barbed J hooks were more efficient at landing fish, and J hooks were more efficient at landing fish than circle hooks. Novice anglers injured proportionally more fish than experienced anglers, primarily during hook removal. Landing time was positively correlated with fish size, and experienced anglers took longer to land fish than novices because they captured larger fish. These results suggest that a reduction in hooking injuries may be achieved by using circle hooks as an alternative to J hooks and barbless J hooks to reduce injury and handling time, yet catch efficiency for both methods would be reduced. Although fish captured with barbless J hooks and circle hooks had fewer injuries, it is important to note that each hook type also caused significant injury, and angler education is recommended to promote proper hook removal techniques.

  9. Final Muon Emittance Exchange in Vacuum for a Collider

    SciTech Connect

    Summers, Don; Acosta, John; Cremaldi, Lucien; Hart, Terry; Oliveros, Sandra; Perera, Lalith; Wu, Wanwei; Neuffer, David

    2015-05-07

    We outline a plan for final muon ionization cooling with quadrupole doublets focusing onto short absorbers followed by emittance exchange in vacuum to achieve the small transverse beam sizes needed by a muon collider. A flat muon beam with a series of quadrupole doublet half cells appears to provide the strong focusing required for final cooling. Each quadrupole doublet has a low β region occupied by a dense, low Z absorber. After final cooling, normalized xyz emittances of (0.071, 0.141, 2.4) mm-rad are exchanged into (0.025, 0.025, 70) mm-rad. Thin electrostatic septa efficiently slice the bunch into 17 parts. The 17 bunches are interleaved into a 3.7 meter long train with RF deflector cavities. Snap bunch coalescence combines the muon bunch train longitudinally in a 21 GeV ring in 55 μs, one quarter of a synchrotron oscillation period. A linear long wavelength RF bucket gives each bunch a different energy causing the bunches to drift until they merge into one bunch and can be captured in a short wavelength RF bucket with a 13% muon decay loss and a packing fraction as high as 87%.

  10. Gamow-Teller transitions from Mg24 and their impact on the electron capture rates in the O+Ne+Mg cores of stars

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Rahman, Muneeb-Ur

    2007-03-01

    Electron captures on nuclei play an important role in the collapse of stellar core in the stages leading to a type-II supernova. Recent observations of subluminous Type II-P supernovae (e.g., 2005cs, 2003gd, 1999br) were able to rekindle the interest in 8 10 M⊙ which develop O+Ne+Mg cores. We used the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory to calculate the B(GT) strength for Mg24 →Na24 and its associated electron capture rates for incorporation in simulation calculations. The calculated rates, in this article, have differences with the earlier reported shell model and Fuller, Fowler, and Newman (hereafter FN2) rates. We compared Gamow-Teller (GT) strength distribution functions and found fairly good agreement with experiment and shell model. However, the GT centroid and the total GT strength, which are useful in the calculation of electron capture rates in the core of massive presupernova stars, lead to the enhancement of our rate up to a factor of 4 compared to the shell model rates at high temperatures and densities.

  11. Measurement of the {beta}{sup +} and Orbital Electron-Capture Decay Rates in Fully Ionized, Hydrogenlike, and Heliumlike {sup 140}Pr Ions

    SciTech Connect

    Litvinov, Yu. A.; Geissel, H.; Winckler, N.; Knoebel, R.; Litvinov, S. A.; Scheidenberger, C.; Bosch, F.; Beckert, K.; Brandau, C.; Dimopoulou, C.; Hess, S.; Kozhuharov, C.; Mazzocco, M.; Nociforo, C.; Nolden, F.; Prochazka, A.; Reuschl, R.; Steck, M.; Stoehlker, T.; Trassinelli, M.

    2007-12-31

    We report on the first measurement of the {beta}{sup +} and orbital electron-capture decay rates of {sup 140}Pr nuclei with the simplest electron configurations: bare nuclei, hydrogenlike, and heliumlike ions. The measured electron-capture decay constant of hydrogenlike {sup 140}Pr{sup 58+} ions is about 50% larger than that of heliumlike {sup 140}Pr{sup 57+} ions. Moreover, {sup 140}Pr ions with one bound electron decay faster than neutral {sup 140}Pr{sup 0+} atoms with 59 electrons. To explain this peculiar observation one has to take into account the conservation of the total angular momentum, since only particular spin orientations of the nucleus and of the captured electron can contribute to the allowed decay.

  12. Research and Development of Future Muon Collider

    SciTech Connect

    Yonehara, K.; /Fermilab

    2012-05-01

    Muon collider is a considerable candidate of the next generation high-energy lepton collider machine. A novel accelerator technology must be developed to overcome several intrinsic issues of muon acceleration. Recent research and development of critical beam elements for a muon accelerator, especially muon beam phase space ionization cooling channel, are reviewed in this paper.

  13. Discovery of temperature-dependent phenomena of muon-catalyzed fusion in solid deuterium and tritium mixtures.

    PubMed

    Kawamura, N; Nagamine, K; Matsuzaki, T; Ishida, K; Nakamura, S N; Matsuda, Y; Tanase, M; Kato, M; Sugai, H; Kudo, K; Takeda, N; Eaton, G H

    2003-01-31

    A systematic experimental study on muon-catalyzed fusion was conducted using a series of solid deuterium and tritium mixtures. A variety of conditions were investigated, i.e., tritium concentrations from 20% to 70%, and temperatures from 5 to 16 K. With decreasing temperature, we observed an unexpected decrease in the muon cycling rate (lambda(c)) and an increase in the muon loss probability (W). The origins of these observed changes were interpreted by the temperature-dependence in the dt mu formation process for lambda(c) and that in the muon reactivation process after muon-to-alpha sticking for W.

  14. Muon Production in Relativistic Cosmic-Ray Interactions

    SciTech Connect

    Klein, Spencer

    2009-07-27

    Cosmic-rays with energies up to 3x1020 eV have been observed. The nuclear composition of these cosmic rays is unknown but if the incident nuclei are protons then the corresponding center of mass energy is sqrt snn = 700 TeV. High energy muons can be used to probe the composition of these incident nuclei. The energy spectra of high-energy (> 1 TeV) cosmic ray induced muons have been measured with deep underground or under-ice detectors. These muons come from pion and kaon decays and from charm production in the atmosphere. Terrestrial experiments are most sensitive to far-forward muons so the production rates aresensitive to high-x partons in the incident nucleus and low-x partons in the nitrogen/oxygen targets. Muon measurements can complement the central-particle data collected at colliders.This paper will review muon production data and discuss some non-perturbative (soft) models that have been used to interpret the data. I will show measurements of TeV muon transverse momentum (pT) spectra in cosmic-ray air showers fromMACRO, and describe how the IceCube neutrino observatory and the proposed Km3Net detector will extend these measurements to a higher pT region where perturbative QCD should apply. With a 1 km2 surface area, the full IceCube detector should observe hundreds of muons/year with pT in the pQCD regime.

  15. The muon-induced neutron indirect detection EXperiment, MINIDEX

    NASA Astrophysics Data System (ADS)

    Abt, I.; Caldwell, A.; Carissimo, C.; Gooch, C.; Kneißl, R.; Langford, J.; Liu, X.; Majorovits, B.; Palermo, M.; Schulz, O.; Vanhoefer, L.

    2017-04-01

    A new experiment to quantitatively measure neutrons induced by cosmic-ray muons in selected high-Z materials is introduced. The design of the Muon-Induced Neutron Indirect Detection EXperiment, MINIDEX, and the results from its first data taking period are presented as well as future plans. Neutron production in high-Z materials is of particular interest as such materials are used for shielding in low-background experiments. The design of next-generation large-scale experiments searching for neutrinoless double beta decay or direct interactions of dark matter requires reliable Monte Carlo simulations of background induced by muon interactions. The first five months of operation already provided a valuable data set on neutron production and neutron transport in lead. A first round of comparisons between MINIDEX data and Monte Carlo predictions obtained with a GEANT4-based package for two different sets of physics models of relevance for neutron production by muons is presented. The rate of muon-induced events is overall a factor three to four higher in data than predicted by the Monte Carlo packages. In addition, the time evolution of the muon-induced signal is not well described by the simulations.

  16. Muon Simulation at the Daya Bay SIte

    SciTech Connect

    Mengyun, Guan; Jun, Cao; Changgen, Yang; Yaxuan, Sun; Luk, Kam-Biu

    2006-05-23

    With a pretty good-resolution mountain profile, we simulated the underground muon background at the Daya Bay site. To get the sea-level muon flux parameterization, a modification to the standard Gaisser's formula was introduced according to the world muon data. MUSIC code was used to transport muon through the mountain rock. To deploy the simulation, first we generate a statistic sample of sea-level muon events according to the sea-level muon flux distribution formula; then calculate the slant depth of muon passing through the mountain using an interpolation method based on the digitized data of the mountain; finally transport muons through rock to get underground muon sample, from which we can get results of muon flux, mean energy, energy distribution and angular distribution.

  17. Cosmic-Ray Muons in the Deep Ocean

    NASA Astrophysics Data System (ADS)

    Clem, John Mason

    1990-01-01

    The purpose of this dissertation is to present the SPS (Short Prototype String) muon data and to compare the data with previous measurements and with the current theories of muon energy losses. The experiment with the SPS was an international collaborative effort, whose purpose was to determine the feasibility of reconstructing muon trajectories in the ocean from measurements, with a sparse array of photomultipliers, of the Cerenkov light from the muons. The successful measurement of the angular distributions and vertical fluxes at several ocean depths by reconstructing muon trajectories from the photomultipler signals demonstrates the feasibility of DUMAND (Deep Underwater Muon And Neutrino Detector). DUMAND will be a large array of photomultipliers anchored to the bottom of the ocean and used to detect the resulting Cerenkov light from high energy muons produced by the neutrino charged current interactions. The search for sources of very high energy neutrinos in the universe will be DUMAND's primary goal. This technique for reconstructing the muon has been successfully applied in several previous experiments with much more closely spaced detectors and with sensitive volumes several orders of magnitude smaller than required by DUMAND. Moreover, the backgrounds from bioluminescence and from 40K decay in the ocean present a very different set of problems for this extension of the technique. The results presented here show that this technique remains practical despite these additional problems. The SPS, which was the first stage of DUMAND, was a vertical string of seven Cerenkov detectors tethered to a ship. The detector achieved an average effective area of 322 +/- 64m^2 . The experiment was performed at the DUMAND site. Muons were successfully detected and reconstructed at depths ranging from 2km to 4km at 500m intervals. The average effective area and the associated muon rate at the respective depths give fluxes consistent with the previous measurements at

  18. Muon Collider Task Force Report

    SciTech Connect

    Ankenbrandt, C.; Alexahin, Y.; Balbekov, V.; Barzi, E.; Bhat, C.; Broemmelsiek, D.; Bross, A.; Burov, A.; Drozhdin, A.; Finley, D.; Geer, S.; /Fermilab /Argonne /Brookhaven /Jefferson Lab /LBL, Berkeley /MUONS Inc., Batavia /UCLA /UC, Riverside /Mississippi U.

    2007-12-01

    Muon Colliders offer a possible long term path to lepton-lepton collisions at center-of-mass energies {radical}s {ge} 1 TeV. In October 2006 the Muon Collider Task Force (MCTF) proposed a program of advanced accelerator R&D aimed at developing the Muon Collider concept. The proposed R&D program was motivated by progress on Muon Collider design in general, and in particular, by new ideas that have emerged on muon cooling channel design. The scope of the proposed MCTF R&D program includes muon collider design studies, helical cooling channel design and simulation, high temperature superconducting solenoid studies, an experimental program using beams to test cooling channel RF cavities and a 6D cooling demonstration channel. The first year of MCTF activities are summarized in this report together with a brief description of the anticipated FY08 R&D activities. In its first year the MCTF has made progress on (1) Muon Collider ring studies, (2) 6D cooling channel design and simulation studies with an emphasis on the HCC scheme, (3) beam preparations for the first HPRF cavity beam test, (4) preparations for an HCC four-coil test, (5) further development of the MANX experiment ideas and studies of the muon beam possibilities at Fermilab, (6) studies of how to integrate RF into an HCC in preparation for a component development program, and (7) HTS conductor and magnet studies to prepare for an evaluation of the prospects for of an HTS high-field solenoid build for a muon cooling channel.

  19. High-Resolution Neutron Capture and Total Cross-Section Measurements, and the Astrophysical 95Mo(n,gamma) Reaction Rate at s-process Temperatures

    SciTech Connect

    Koehler, Paul Edward; Guber, Klaus H; Harvey, John A; Wiarda, Dorothea

    2008-01-01

    Abundances of Mo isotopes predicted by stellar models of the s process are, except for {sup 95}Mo, in good agreement with data from single grains of mainstream presolar SiC. Because the meteorite data seemed sound and no reasonable modification to stellar theory resulted in good agreement for {sup 95}Mo, it has been suggested that the recommended neutron capture reaction rate for this nuclide is 30% too low. Therefore, we have made a new determination of the {sup 95}Mo(n,{gamma}) reaction rate via high-resolution measurements of the neutron-capture and total cross sections of {sup 95}Mo at the Oak Ridge Electron Linear Accelerator. These data were analyzed with the R-matrix code SAMMY to obtain parameters for resonances up to E{sub n} = 10 keV. Also, a small change to our capture apparatus allowed us to employ a new technique to vastly improve resonance spin and parity assignments. These new resonance parameters, together with our data in the unresolved range, were used to calculate the {sup 95}Mo(n,{gamma}) reaction rate at s-process temperatures. We compare the currently recommended rate to our new results and discuss their astrophysical impact.

  20. DETECTORS AND EXPERIMENTAL METHODS: Track reconstruction in the BESIII muon counter

    NASA Astrophysics Data System (ADS)

    Liang, Yu-Tie; Liu, Kun; You, Zheng-Yun; Mao, Ya-Jun; Li, Wei-Dong; Bian, Jian-Ming; Cao, Guo-Fu; Cao, Xue-Xiang; Chen, Shen-Jian; Deng, Zi-Yan; Fu, Cheng-Dong; Gao, Yuan-Ning; Han, Lei; Han, Shao-Qing; He, Kang-Lin; He, Miao; Hu, Ji-Feng; Hu, Xiao-Wei; Huang, Bin; Huang, Xing-Tao; Jia, Lu-Kui; Ji, Xiao-Bin; Li, Hai-Bo; Liu, Bei-Jiang; Liu, Chun-Xiu; Liu, Huai-Min; Liu, Ying; Liu, Yong; Luo, Tao; Lu, Qi-Wen; Ma, Qiu-Mei; Ma, Xiang; Mao, Ze-Pu; Mo, Xiao-Hu; Ning, Fei-Peng; Ping, Rong-Gang; Qiu, Jin-Fa; Song, Wen-Bo; Sun, Sheng-Sen; Sun, Xiao-Dong; Sun, Yong-Zhao; Tian, Hao-Lai; Wang, Ji-Ke; Wang, Liang-Liang; Wen, Shuo-Pin; Wu, Ling-Hui; Wu, Zhi; Xie, Yu-Guang; Xu, Min; Yan, Jie; Yan, Liang; Yao, Jian; Yuan, Chang-Zheng; Yuan, Ye; Zhang, Chang-Chun; Zhang, Jian-Yong; Zhang, Lei; Zhang, Xue-Yao; Zhang, Yao; Zheng, Yang-Heng; Zhu, Yong-Sheng; Zou, Jia-Heng

    2009-08-01

    The reconstruction algorithm for BESIII Muon Counter, MucRecAlg, is developed with the object-oriented language C++ in BESIII offline software environment. MucRecAlg consists of the following functions: to find track seeds either from extrapolation of tracks in the main drift chamber or from the fired strips in muon counter, to select fired strips associated to the candidate tracks, to fit the candidate tracks with a linear or quadratic function and to calculate other parameters of the tracks for muon identification. Monte Carlo samples are generated to check the performance of the reconstruction package, such as reconstruction efficiency, muon remaining rate and pion rejection rate, etc. The preliminary results show that the pion rejection rate is around 3%-4% while the muon remaining rate is better than 90% in 0.4-1.6 GeV/c momentum region, which meets the requirement as shown in the design report.

  1. Measurement of the positive muon lifetime and determination of the Fermi constant to part-per-million precision.

    PubMed

    Webber, D M; Tishchenko, V; Peng, Q; Battu, S; Carey, R M; Chitwood, D B; Crnkovic, J; Debevec, P T; Dhamija, S; Earle, W; Gafarov, A; Giovanetti, K; Gorringe, T P; Gray, F E; Hartwig, Z; Hertzog, D W; Johnson, B; Kammel, P; Kiburg, B; Kizilgul, S; Kunkle, J; Lauss, B; Logashenko, I; Lynch, K R; McNabb, R; Miller, J P; Mulhauser, F; Onderwater, C J G; Phillips, J; Rath, S; Roberts, B L; Winter, P; Wolfe, B

    2011-01-28

    We report a measurement of the positive muon lifetime to a precision of 1.0 ppm; it is the most precise particle lifetime ever measured. The experiment used a time-structured, low-energy muon beam and a segmented plastic scintillator array to record more than 2×10(12) decays. Two different stopping target configurations were employed in independent data-taking periods. The combined results give τ(μ(+)) (MuLan)=2 196 980.3(2.2)  ps, more than 15 times as precise as any previous experiment. The muon lifetime gives the most precise value for the Fermi constant: G(F) (MuLan)=1.166 378 8(7)×10(-5)  GeV(-2) (0.6 ppm). It is also used to extract the μ(-)p singlet capture rate, which determines the proton's weak induced pseudoscalar coupling g(P).

  2. Simulation studies of muon-produced background events deep underground and consequences for double beta decay experiments

    NASA Astrophysics Data System (ADS)

    Massarczyk, Ralph; Majorana Collaboration

    2015-10-01

    Cosmic radiation creates a significant background for low count rate experiments. The Majorana demonstrator experiment is located at the Sanford Underground Research Facility at a depth of 4850ft below the surface but it can still be penetrated by cosmic muons with initial energies above the TeV range. The interaction of muons with the rock, the shielding material in the lab and the detector itself can produce showers of secondary particles, like fast neutrons, which are able to travel through shielding material and can produce high-energy γ-rays via capture or inelastic scattering. The energy deposition of these γ rays in the detector can overlap with energy region of interest for the neutrino-less double beta decay. Recent studies for cosmic muons penetrating the Majorana demonstrator are made with the Geant4 code. The results of these simulations will be presented in this talk and an overview of the interaction of the shower particles with the detector, shielding and veto system will be given. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, the Particle Astrophysics Program of the National Science Foundation, and the Sanford Underground Research Facility. Supported by U.S. Department of Energy through the LANL/LDRD Program.

  3. Muon Colliders and Neutrino Factories

    SciTech Connect

    Kaplan, Daniel M.

    2015-05-29

    Muon colliders and neutrino factories are attractive options for future facilities aimed at achieving the highest lepton-antilepton collision energies and precision measurements of Higgs boson and neutrino mixing matrix parameters. The facility performance and cost depend on how well a beam of muons can be cooled. Recent progress in muon cooling design studies and prototype tests nourishes the hope that such facilities could be built starting in the coming decade. The status of the key technologies and their various demonstration experiments is summarized. Prospects "post-P5" are also discussed.

  4. Measurement of muon intensity by Cerenkov method

    NASA Technical Reports Server (NTRS)

    Liu, Z. H.; Li, G. J.; Bai, G. Z.; Liu, J. G.; Geng, Q. X.; Ling, J.

    1985-01-01

    Optical detection is an important technique in studies and observations of air showers, muons and relevant phenomena. The muon intensity is measured in a proper energy range and to study some problems about Cerenkov radiation of cosmic rays are studied, by a muon-telescope operated with Cerenkov detector. It is found that the measured muon intensity agrees with the integral energy spectrum of cosmic ray muons.

  5. Muon ID - taking care of lower momenta muons

    SciTech Connect

    Milstene, C.; Fisk, G.; Para, A.; /Fermilab

    2005-12-01

    In the Muon package under study, the tracks are extrapolated using an algorithm which accounts for the magnetic field and the ionization (dE/dx). We improved the calculation of the field dependent term to increase the muon detection efficiency at lower momenta using a Runge-Kutta method. The muon identification and hadron separation in b-bbar jets is reported with the improved software. In the same framework, the utilization of the Kalman filter is introduced. The principle of the Kalman filter is described in some detail with the propagation matrix, with the Runge-Kutta term included, and the effect on low momenta for low momenta single muons particles is described.

  6. Muon identification with Muon Telescope Detector at the STAR experiment

    DOE PAGES

    Huang, T. C.; Ma, R.; Huang, B.; ...

    2016-07-15

    The Muon Telescope Detector (MTD) is a newly installed detector in the STAR experiment. It provides an excellent opportunity to study heavy quarkonium physics using the dimuon channel in heavy ion collisions. In this paper, we report the muon identification performance for the MTD using proton-proton collisions atmore » $$\\sqrt{s}$$ = 500 GeV with various methods. Here, the result using the Likelihood Ratio method shows that the muon identification efficiency can reach up to ~ 90% for muons with transverse momenta greater than 3 GeV/c and the significance of the J/ψ signal is improved by a factor of 2 compared to using the basic selection.« less

  7. Measurement of cosmic-ray muons and muon-induced neutrons in the Aberdeen Tunnel Underground Laboratory

    SciTech Connect

    Yeh, M.; Chan, Y. L.; Chen, X. C.; Chu, M. C.; Cui, K. X.; Hahn, R. L.; Ho, T. H.; Hsiung, Y. B.; Hu, B. Z.; Kwan, K. K.; Kwok, M. W.; Kwok, T.; Lau, Y. P.; Leung, J. K. C.; Leung, K. Y.; Lin, G. L.; Lin, Y. C.; Luk, K. B.; Luk, W. H.; Ngai, H. Y.; Ngan, S. Y.; Pun, C. S. J.; Shih, K.; Tam, Y. H.; Tsang, R. H. M.; Wang, C. H.; Wong, C. M.; Wong, H. L. H.; Wong, K. K.; Zhang, B. J.

    2016-04-07

    In this study, we have measured the muon flux and production rate of muon-induced neutrons at a depth of 611 m water equivalent. Our apparatus comprises three layers of crossed plastic scintillator hodoscopes for tracking the incident cosmic-ray muons and 760 L of a gadolinium-doped liquid scintillator for producing and detecting neutrons. The vertical muon intensity was measured to be Iμ = (5.7±0.6)×10–6 cm–2 s–1 sr–1. The yield of muon-induced neutrons in the liquid scintillator was determined to be Yn = (1.19 ± 0.08(stat) ± 0.21(syst)) × 10–4 neutrons/(μ•g•cm–2). A fit to the recently measured neutron yields at different depths gave a mean muon energy dependence of < Eμ >0.76±0.03 for liquid-scintillator targets.

  8. Simulation of Underground Muon Flux with Application to Muon Tomography

    NASA Astrophysics Data System (ADS)

    Yamaoka, J. A. K.; Bonneville, A.; Flygare, J.; Lintereur, A.; Kouzes, R.

    2015-12-01

    Muon tomography uses highly energetic muons, produced by cosmic rays interacting within the upper atmosphere, to image dense materials. Like x-rays, an image can be constructed from the negative of the absorbed (or scattered) muons. Unlike x-rays, these muons can penetrate thousands of meters of earth. Muon tomography has been shown to be useful across a wide range of applications (such as imaging of the interior of volcanoes and cargo containers). This work estimates the sensitivity of muon tomography for various underground applications. We use simulations to estimate the change in flux as well as the spatial resolution when imaging static objects, such as mine shafts, and dynamic objects, such as a CO2 reservoir filling over time. We present a framework where we import ground density data from other sources, such as wells, gravity and seismic data, to generate an expected muon flux distribution at specified underground locations. This information can further be fed into a detector simulation to estimate a final experimental sensitivity. There are many applications of this method. We explore its use to image underground nuclear test sites, both the deformation from the explosion as well as the supporting infrastructure (access tunnels and shafts). We also made estimates for imaging a CO2 sequestration site similar to Futuregen 2.0 in Illinois and for imaging magma chambers beneath the Cascade Range volcanoes. This work may also be useful to basic science, such as underground dark matter experiments, where increasing experimental sensitivity requires, amongst other factors, a precise knowledge of the muon background.

  9. Precision muon tracking detectors for high-energy hadron colliders

    NASA Astrophysics Data System (ADS)

    Gadow, Ph.; Kortner, O.; Kroha, H.; Richter, R.

    2017-02-01

    Small-diameter muon drift tube (sMDT) chambers with 15 mm tube diameter are a cost-effective technology for high-precision muon tracking over large areas at high background rates as expected at future high-energy hadron colliders including HL-LHC. The chamber design and construction procedures have been optimised for mass production and provide sense wire positioning accuracy of better than 10 μm. The rate capability of the sMDT chambers has been extensively tested at the CERN Gamma Irradiation Facility. It exceeds the one of the ATLAS muon drift tube (MDT) chambers, which are operated at unprecedentedly high background rates of neutrons and γ-rays, by an order of magnitude, which is sufficient for almost the whole of the muon detector acceptance at FCC-hh at maximum luminosity. sMDT operational and construction experience exists from ATLAS muon spectrometer upgrades which are in progress or under preparation for LHC Phase 1 and 2.

  10. Dose from slow negative muons.

    PubMed

    Siiskonen, T

    2008-01-01

    Conversion coefficients from fluence to ambient dose equivalent, from fluence to maximum dose equivalent and quality factors for slow negative muons are examined in detail. Negative muons, when stopped, produce energetic photons, electrons and a variety of high-LET particles. Contribution from each particle type to the dose equivalent is calculated. The results show that for the high-LET particles the details of energy spectra and decay yields are important for accurate dose estimates. For slow negative muons the ambient dose equivalent does not always yield a conservative estimate for the protection quantities. Especially, the skin equivalent dose is strongly underestimated if the radiation-weighting factor of unity for slow muons is used. Comparisons to earlier studies are presented.

  11. Muon spin rotation in solids

    NASA Technical Reports Server (NTRS)

    Stronach, C. E.

    1983-01-01

    The muon spin rotation (MuSR) technique is used to probe the microscopic electron density in materials. High temperature MuSR and magnetization measurements in nickel are in progress to allow an unambiguous determination of the muon impurity interaction and the impurity induced change in local spin density. The first results on uniaxial stress induced frequency shifts in an Fe single crystal are also reported.

  12. The muon and the electron

    NASA Astrophysics Data System (ADS)

    Hughes, V. W.

    Our present understanding of the muon and of its relationship to the electron is reviewed, with particular emphasis on the contributions of atomic physics to this topic. A large body of precise experimental data has been obtained, and all this evidence still indicates that the muon is a pointlike lepton which has the same electroweak interactions given by the standard theory as does the electron, and hence the muon differs from the electron only in its larger mass. There is as yet no understanding of the relationship of the muon (or tau particle) to the electron, or of a spectrum comprising these apparently independent lepton generations. Nous rappelons ce qui est actuellement compris du muon et de sa relation avec l'électron, en insistant sur les contributions de la Physique Atomique à ce sujet. Une large masse de données expérimentales est maintenant acquise, et tout concourt à indiquer que le muon est une particule ponctuelle qui a les mêmes interactions électrofaibles, données par la théorie standard, que l'électron, et ainsi que le muon ne diffère de l'électron que par une masse plus grande. Il n'y a jusqu'à présent aucune interprétation de cette relation du muon (ou de la particule tau) avec l'électron, ou d'un spectre comprenant ces générations de leptons apparemment indépendants.

  13. Muon Colliders: The Next Frontier

    ScienceCinema

    Tourun, Yagmur [Illinois Institute of Technology, Chicago, Illinois, United States

    2016-07-12

    Muon Colliders provide a path to the energy frontier in particle physics but have been regarded to be "at least 20 years away" for 20 years. I will review recent progress in design studies and hardware R&D and show that a Muon Collider can be established as a real option for the post-LHC era if the current vigorous R&D effort revitalized by the Muon Collider Task Force at Fermilab can be supported to its conclusion. All critical technologies are being addressed and no show-stoppers have emerged. Detector backgrounds have been studied in detail and appear to be manageable and the physics can be done with existing detector technology. A muon facility can be built through a staged scenario starting from a low-energy muon source with unprecedented intensity for exquisite reach for rare processes, followed by a Neutrino Factory with ultrapure neutrino beams with unparalleled sensitivity for disentangling neutrino mixing, leading to an energy frontier Muon Collider with excellent energy resolution.

  14. Measurement of the solar neutrino capture rate with gallium metal. III. Results for the 2002-2007 data-taking period

    NASA Astrophysics Data System (ADS)

    Abdurashitov, J. N.; Gavrin, V. N.; Gorbachev, V. V.; Gurkina, P. P.; Ibragimova, T. V.; Kalikhov, A. V.; Khairnasov, N. G.; Knodel, T. V.; Mirmov, I. N.; Shikhin, A. A.; Veretenkin, E. P.; Yants, V. E.; Zatsepin, G. T.; Bowles, T. J.; Elliott, S. R.; Teasdale, W. A.; Nico, J. S.; Cleveland, B. T.; Wilkerson, J. F.

    2009-07-01

    The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in December 1989. Measurements have continued with only a few brief interruptions since that time. In this article we present the experimental improvements in SAGE since its last published data summary in December 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through December 2007 gives a capture rate of solar neutrinos with energy more than 233 keV of 65.4-3.0+3.1 (stat) -2.8+2.6 (syst) SNU. The weighted average of the results of all three Ga solar neutrino experiments, SAGE, Gallex, and GNO, is now 66.1±3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced Ar37 neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in the three prior Cr51 neutrino-source experiments with Ga, is 0.87±0.05. A probable explanation for this low result is that the cross section for neutrino capture by the two lowest-lying excited states in Ge71 has been overestimated. If we assume these cross sections are zero, then the standard solar model including neutrino oscillations predicts a total capture rate in Ga in the range of 63 SNU to 66 SNU with an uncertainty of about 4%, in good agreement with experiment. We derive the current value of the neutrino flux produced in the Sun by the proton-proton fusion reaction to be ϕpp⊙=(6.0±0.8)×1010/(cm2s), which agrees well with the pp flux predicted by the standard solar model. Finally, we make several tests and show that the data are consistent with the assumption that the solar neutrino production rate is constant in time.

  15. Measurement of the solar neutrino capture rate with gallium metal. III. Results for the 2002-2007 data-taking period

    SciTech Connect

    Abdurashitov, J. N.; Gavrin, V. N.; Gorbachev, V. V.; Gurkina, P. P.; Ibragimova, T. V.; Kalikhov, A. V.; Khairnasov, N. G.; Knodel, T. V.; Mirmov, I. N.; Shikhin, A. A.; Veretenkin, E. P.; Yants, V. E.; Zatsepin, G. T.; Bowles, T. J.; Elliott, S. R.; Teasdale, W. A.; Nico, J. S.; Cleveland, B. T.; Wilkerson, J. F.

    2009-07-15

    The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in December 1989. Measurements have continued with only a few brief interruptions since that time. In this article we present the experimental improvements in SAGE since its last published data summary in December 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through December 2007 gives a capture rate of solar neutrinos with energy more than 233 keV of 65.4{sub -3.0}{sup +3.1} (stat) {sub -2.8}{sup +2.6} (syst) SNU. The weighted average of the results of all three Ga solar neutrino experiments, SAGE, Gallex, and GNO, is now 66.1{+-}3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced {sup 37}Ar neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in the three prior {sup 51}Cr neutrino-source experiments with Ga, is 0.87{+-}0.05. A probable explanation for this low result is that the cross section for neutrino capture by the two lowest-lying excited states in {sup 71}Ge has been overestimated. If we assume these cross sections are zero, then the standard solar model including neutrino oscillations predicts a total capture rate in Ga in the range of 63 SNU to 66 SNU with an uncertainty of about 4%, in good agreement with experiment. We derive the current value of the neutrino flux produced in the Sun by the proton-proton fusion reaction to be {phi}{sub pp}{sup {center_dot}}=(6.0{+-}0.8)x10{sup 10}/(cm{sup 2} s), which agrees well with the pp flux predicted by the standard solar model. Finally, we make several tests and show that the data are consistent with the assumption that the solar neutrino production rate is constant in time.

  16. Experimental investigation of muon-catalyzed t + t fusion

    SciTech Connect

    Bogdanova, L. N.; Bom, V. R.; Demin, A. M.; Demin, D. L.; Eijk, C. W. E. van; Filchagin, S. V.; Filchenkov, V. V.; Grafov, N. N. Grishechkin, S. K.; Gritsaj, K. I.; Konin, A. D.; Kuryakin, A. V.; Medved', S. V.; Musyaev, R. K.; Rudenko, A. I.; Tumkin, D. P.; Vinogradov, Yu. I.; Yukhimchuk, A. A.; Yukhimchuk, S. A.; Zinov, V. G.

    2009-02-15

    The muon-catalyzed fusion ({mu}CF) process in tritium was studied by the {mu}CF collaboration on the muon beam of the JINR Phasotron. The measurements were carried out with a liquid tritium target at the temperature 22 K and density approximately 1.25 of the liquid hydrogen density (LHD). Parameters of the {mu}CF cycle were determined: the tt{mu} muonic molecule formation rate {lambda}{sub tt{mu}} = 2.84(0.32) {mu}s{sup -1}, the tt{mu} fusion reaction rate {lambda}{sub f} = 15.6(2.0) {mu}s{sup -1}, and the probability of muon sticking to helium {omega}{sub tt}= 13.9(1.5)%. The results agree with those obtained earlier by other groups, but better accuracy was achieved due to our unique experimental method.

  17. Injection deep level transient spectroscopy: An improved method for measuring capture rates of hot carriers in semiconductors

    SciTech Connect

    Fleming, R. M.; Seager, C. H.; Lang, D. V.; Campbell, J. M.

    2015-07-02

    In this study, an improved method for measuring the cross sections for carrier trapping at defects in semiconductors is described. This method, a variation of deep level transient spectroscopy(DLTS) used with bipolar transistors, is applied to hot carrier trapping at vacancy-oxygen, carbon-oxygen, and three charge states of divacancy centers (V2) in n- and p-type silicon. Unlike standard DLTS, we fill traps by injecting carriers into the depletion region of a bipolar transistor diode using a pulse of forward bias current applied to the adjacent diode. We show that this technique is capable of accurately measuring a wide range of capture cross sections at varying electric fields due to the control of the carrier density it provides. Because this technique can be applied to a variety of carrier energy distributions, it should be valuable in modeling the effect of radiation-induced generation-recombination currents in bipolar devices.

  18. Injection deep level transient spectroscopy: An improved method for measuring capture rates of hot carriers in semiconductors

    NASA Astrophysics Data System (ADS)

    Fleming, R. M.; Seager, C. H.; Lang, D. V.; Campbell, J. M.

    2015-07-01

    An improved method for measuring the cross sections for carrier trapping at defects in semiconductors is described. This method, a variation of deep level transient spectroscopy (DLTS) used with bipolar transistors, is applied to hot carrier trapping at vacancy-oxygen, carbon-oxygen, and three charge states of divacancy centers (V2) in n- and p-type silicon. Unlike standard DLTS, we fill traps by injecting carriers into the depletion region of a bipolar transistor diode using a pulse of forward bias current applied to the adjacent diode. We show that this technique is capable of accurately measuring a wide range of capture cross sections at varying electric fields due to the control of the carrier density it provides. Because this technique can be applied to a variety of carrier energy distributions, it should be valuable in modeling the effect of radiation-induced generation-recombination currents in bipolar devices.

  19. Injection deep level transient spectroscopy: An improved method for measuring capture rates of hot carriers in semiconductors

    SciTech Connect

    Fleming, R. M.; Seager, C. H.; Lang, D. V.; Campbell, J. M.

    2015-07-07

    An improved method for measuring the cross sections for carrier trapping at defects in semiconductors is described. This method, a variation of deep level transient spectroscopy (DLTS) used with bipolar transistors, is applied to hot carrier trapping at vacancy-oxygen, carbon-oxygen, and three charge states of divacancy centers (V{sub 2}) in n- and p-type silicon. Unlike standard DLTS, we fill traps by injecting carriers into the depletion region of a bipolar transistor diode using a pulse of forward bias current applied to the adjacent diode. We show that this technique is capable of accurately measuring a wide range of capture cross sections at varying electric fields due to the control of the carrier density it provides. Because this technique can be applied to a variety of carrier energy distributions, it should be valuable in modeling the effect of radiation-induced generation-recombination currents in bipolar devices.

  20. Design of an intense muon source with a carbon and mercury target

    SciTech Connect

    Stratakis, D.; Berg, J. S.; Neuffer, D.; Ding, X.

    2015-05-03

    In high-intensity sources, muons are produced by firing high energy protons onto a target to produce pions. The pions decay to muons which are captured and accelerated. In the present study, we examine the performance of the channel for two different target scenarios: one based on liquid mercury and another one based on a solid carbon target. We produce distributions with the two different target materials and discuss differences in particle spectrum near the sources. We then propagate the distributions through our capture system and compare the full system performance for the two target types.

  1. Design of an Intense Muon Source with a Carbon and Mercury Target

    SciTech Connect

    Stratakis, Diktys; Berg, J. Scott; Neuffer, David; Ding, Xiaoping

    2015-06-01

    In high-intensity sources, muons are produced by firing high energy protons onto a target to produce pions. The pions decay to muons which are captured and accelerated. In the present study, we examine the performance of the channel for two different target scenarios: one based on liquid mercury and another one based on a solid carbon target. We produce distributions with the two different target materials and discuss differences in particle spectrum near the sources. We then propagate the distributions through our capture system and compare the full system performance for the two target types.

  2. Muon Tomography for Geological Repositories.

    NASA Astrophysics Data System (ADS)

    Woodward, D.; Kudryavtsev, V.; Gluyas, J.; Clark, S. J.; Thompson, L. F.; Klinger, J.; Spooner, N. J.; Blackwell, T. B.; Pal, S.; Lincoln, D. L.; Paling, S. M.; Mitchell, C. N.; Benton, C.; Coleman, M. L.; Telfer, S.; Cole, A.; Nolan, S.; Chadwick, P.

    2015-12-01

    Cosmic-ray muons are subatomic particles produced in the upper atmosphere in collisions of primary cosmic rays with atoms in air. Due to their high penetrating power these muons can be used to image the content (primarily density) of matter they pass through. They have already been used to image the structure of pyramids, volcanoes and other objects. Their applications can be extended to investigating the structure of, and monitoring changes in geological formations and repositories, in particular deep subsurface sites with stored CO2. Current methods of monitoring subsurface CO2, such as repeat seismic surveys, are episodic and require highly skilled personnel to operate. Our simulations based on simplified models have previously shown that muon tomography could be used to continuously monitor CO2 injection and migration and complement existing technologies. Here we present a simulation of the monitoring of CO2 plume evolution in a geological reservoir using muon tomography. The stratigraphy in the vicinity of the reservoir is modelled using geological data, and a numerical fluid flow model is used to describe the time evolution of the CO2 plume. A planar detection region with a surface area of 1000 m2 is considered, at a vertical depth of 776 m below the seabed. We find that one year of constant CO2 injection leads to changes in the column density of about 1%, and that the CO2 plume is already resolvable with an exposure time of less than 50 days. The attached figure show a map of CO2 plume in angular coordinates as reconstructed from observed muons. In parallel with simulation efforts, a small prototype muon detector has been designed, built and tested in a deep subsurface laboratory. Initial calibrations of the detector have shown that it can reach the required angular resolution for muon detection. Stable operation in a small borehole within a few months has been demonstrated.

  3. End-to-end simulation of bunch merging for a muon collider

    SciTech Connect

    Bao, Yu; Stratakis, Diktys; Hanson, Gail G.; Palmer, Robert B.

    2015-05-03

    Muon accelerator beams are commonly produced indirectly through pion decay by interaction of a charged particle beam with a target. Efficient muon capture requires the muons to be first phase-rotated by rf cavities into a train of 21 bunches with much reduced energy spread. Since luminosity is proportional to the square of the number of muons per bunch, it is crucial for a Muon Collider to use relatively few bunches with many muons per bunch. In this paper we will describe a bunch merging scheme that should achieve this goal. We present for the first time a complete end-to-end simulation of a 6D bunch merger for a Muon Collider. The 21 bunches arising from the phase-rotator, after some initial cooling, are merged in longitudinal phase space into seven bunches, which then go through seven paths with different lengths and reach the final collecting "funnel" at the same time. The final single bunch has a transverse and a longitudinal emittance that matches well with the subsequent 6D rectilinear cooling scheme.

  4. Measurement of the front-end dead-time of the LHCb muon detector and evaluation of its contribution to the muon detection inefficiency

    NASA Astrophysics Data System (ADS)

    Anderlini, L.; Anelli, M.; Archilli, F.; Auriemma, G.; Baldini, W.; Bencivenni, G.; Bizzeti, A.; Bocci, V.; Bondar, N.; Bonivento, W.; Bochin, B.; Bozzi, C.; Brundu, D.; Cadeddu, S.; Campana, P.; Carboni, G.; Cardini, A.; Carletti, M.; Casu, L.; Chubykin, A.; Ciambrone, P.; Dané, E.; De Simone, P.; Falabella, A.; Felici, G.; Fiore, M.; Fontana, M.; Fresch, P.; Furfaro, E.; Graziani, G.; Kashchuk, A.; Kotriakhova, S.; Lai, A.; Lanfranchi, G.; Loi, A.; Maev, O.; Manca, G.; Martellotti, G.; Neustroev, P.; Oldeman, R. G. C.; Palutan, M.; Passaleva, G.; Penso, G.; Pinci, D.; Polycarpo, E.; Saitta, B.; Santacesaria, R.; Santimaria, M.; Santovetti, E.; Saputi, A.; Sarti, A.; Satriano, C.; Satta, A.; Schmidt, B.; Schneider, T.; Sciascia, B.; Sciubba, A.; Siddi, B. G.; Tellarini, G.; Vacca, C.; Vazquez-Gomez, R.; Vecchi, S.; Veltri, M.; Vorobyev, A.

    2016-04-01

    A method is described which allows to deduce the dead-time of the front-end electronics of the LHCb muon detector from a series of measurements performed at different luminosities at a bunch-crossing rate of 20 MHz. The measured values of the dead-time range from ~ 70 ns to ~ 100 ns. These results allow to estimate the performance of the muon detector at the future bunch-crossing rate of 40 MHz and at higher luminosity.

  5. Limits on a muon flux from Kaluza-Klein dark matter annihilations in the Sun from the IceCube 22-string detector

    SciTech Connect

    IceCube Collaboration; Abbasi, R.; al., et

    2009-10-23

    A search for muon neutrinos from Kaluza-Klein dark matter annihilations in the Sun has been performed with the 22-string configuration of the IceCube neutrino detector using data collected in 104.3 days of live-time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured lightest Kaluza-Klein particle (LKP) WIMPs in the Sun and converted to limits on the LKP-proton cross-sections for LKP masses in the range 250 - 3000 GeV. These results are the most stringent limits to date on LKP annihilation in the Sun.

  6. Muon-muon and other high energy colliders

    SciTech Connect

    Palmer, R.B.; Gallardo, J.C.

    1997-02-01

    The first section looks at the high energy physics advantages, disadvantages and luminosity requirements of hadron, of lepton and photon-photon colliders for comparison. The second section discusses the physics considerations for the muon collider. The third section covers muon collider components. The fourth section is about the intersection region and detectors. In the fifth section, the authors discuss modifications to enhance the muon polarization`s operating parameters with very small momentum spreads, operations at energies other than the maximum for which the machine is designed, and designs of machines for different maximum energies. The final section discusses a Research and Development plan aimed at the operation of a 0.5 TeV demonstration machine by the year 2010, and of the 4 TeV machine by the year 2020.

  7. A new X-ray fluorescence spectroscopy for extraterrestrial materials using a muon beam

    PubMed Central

    Terada, K.; Ninomiya, K.; Osawa, T.; Tachibana, S.; Miyake, Y.; Kubo, M. K.; Kawamura, N.; Higemoto, W.; Tsuchiyama, A.; Ebihara, M.; Uesugi, M.

    2014-01-01

    The recent development of the intense pulsed muon source at J-PARC MUSE, Japan Proton Accelerator Research Complex/MUon Science Establishment (106 s−1 for a momentum of 60 MeV/c), enabled us to pioneer a new frontier in analytical sciences. Here, we report a non-destructive elemental analysis using µ− capture. Controlling muon momentum from 32.5 to 57.5 MeV/c, we successfully demonstrate a depth-profile analysis of light elements (B, C, N, and O) from several mm-thick layered materials and non-destructive bulk analyses of meteorites containing organic materials. Muon beam analysis, enabling a bulk analysis of light to heavy elements without severe radioactivation, is a unique analytical method complementary to other non-destructive analyses. Furthermore, this technology can be used as a powerful tool to identify the content and distribution of organic components in future asteroidal return samples. PMID:24861282

  8. A new X-ray fluorescence spectroscopy for extraterrestrial materials using a muon beam.

    PubMed

    Terada, K; Ninomiya, K; Osawa, T; Tachibana, S; Miyake, Y; Kubo, M K; Kawamura, N; Higemoto, W; Tsuchiyama, A; Ebihara, M; Uesugi, M

    2014-05-27

    The recent development of the intense pulsed muon source at J-PARC MUSE, Japan Proton Accelerator Research Complex/MUon Science Establishment (10(6) s(-1) for a momentum of 60 MeV/c), enabled us to pioneer a new frontier in analytical sciences. Here, we report a non-destructive elemental analysis using µ(-) capture. Controlling muon momentum from 32.5 to 57.5 MeV/c, we successfully demonstrate a depth-profile analysis of light elements (B, C, N, and O) from several mm-thick layered materials and non-destructive bulk analyses of meteorites containing organic materials. Muon beam analysis, enabling a bulk analysis of light to heavy elements without severe radioactivation, is a unique analytical method complementary to other non-destructive analyses. Furthermore, this technology can be used as a powerful tool to identify the content and distribution of organic components in future asteroidal return samples.

  9. A new X-ray fluorescence spectroscopy for extraterrestrial materials using a muon beam

    NASA Astrophysics Data System (ADS)

    Terada, K.; Ninomiya, K.; Osawa, T.; Tachibana, S.; Miyake, Y.; Kubo, M. K.; Kawamura, N.; Higemoto, W.; Tsuchiyama, A.; Ebihara, M.; Uesugi, M.

    2014-05-01

    The recent development of the intense pulsed muon source at J-PARC MUSE, Japan Proton Accelerator Research Complex/MUon Science Establishment (106 s-1 for a momentum of 60 MeV/c), enabled us to pioneer a new frontier in analytical sciences. Here, we report a non-destructive elemental analysis using µ- capture. Controlling muon momentum from 32.5 to 57.5 MeV/c, we successfully demonstrate a depth-profile analysis of light elements (B, C, N, and O) from several mm-thick layered materials and non-destructive bulk analyses of meteorites containing organic materials. Muon beam analysis, enabling a bulk analysis of light to heavy elements without severe radioactivation, is a unique analytical method complementary to other non-destructive analyses. Furthermore, this technology can be used as a powerful tool to identify the content and distribution of organic components in future asteroidal return samples.

  10. An all-aqueous route to polymer brush-modified membranes with remarkable permeabilites and protein capture rates

    PubMed Central

    Anuraj, Nishotha; Bhattacharjee, Somnath; Geiger, James H.; Baker, Gregory L.; Bruening, Merlin L.

    2011-01-01

    Microporous membranes are attractive for protein purification because convection rapidly brings proteins to binding sites. However, the low binding capacity of such membranes limits their applications. This work reports a rapid, aqueous procedure to create highly permeable, polymer brush-modified membranes that bind large amounts of protein. The synthetic method includes a 10-min adsorption of a macroinitiator in a hydroxylated nylon membrane and a subsequent 5-min aqueous atom transfer radical polymerization of 2-(methacryloyloxy)ethyl succinate from the immobilized initiator to form poly(acid) brushes. This procedure likely leads to more swollen, less dense brushes than polymerization from silane initiators, and thus requires less polymer to achieve the same binding capacity. The hydraulic permeability of the poly(acid) membranes is 4-fold higher than that of similar membranes prepared by growing brushes from immobilized silane initiators. These brush-containing nylon membranes bind 120 mg/cm3 of lysozyme using solution residence times as short as 35 ms, and when functionalized with nitrilotriacetate (NTA)-Ni2+ complexes, they capture 85 mg/cm3 of histidine6-tagged (His-tagged) Ubiquitin. Additionally the NTA-Ni2+-functionalized membranes isolate His-tagged myo-inositol-1-phosphate synthase directly from cell extracts and show >90% recovery of His-tagged proteins. PMID:22287817

  11. Effect of release rate and ratio of (Z)-11-hexadecen-1-ol from synthetic pheromone blends on trap capture ofHeliothis subflexa (Lepidoptera: Noctuidae).

    PubMed

    Heath, R R; Mitchell, E R; Cibrian Tovar, J

    1990-04-01

    Response of maleHeliothis subflexa to pheromone-baited traps containing blends of tetradecanal, (Z)-9-tetradecanal, hexadecanal, (Z)-7-hexadecenal, (Z)-9-hexadecenal, (Z)-11-hexadecenal, hexadecan-1-ol acetate, (Z)-7-hexadecen-1-ol acetate, (Z)-9-hexadecen-1-ol acetate, (Z)-11-hexadecen-1-ol acetate, (Z)-9-hexadecen-1-ol, and (Z)-11-hexadecen-1-ol was evaluated. Analysis of trap capture data indicated that (Z)-11-hexadecen-1-ol was a critical component of the pheromone blend. It was determined from emission rate data and measurements of the ratio of pheromone components emitted from rubber septa tested that a significant increase in trap capture of maleH. subflexa occurred when the blends investigated released the alcohol in a narrow range relative to the total amount of pheromone emitted. The optimum range of release ratio of the alcohol for the capture of males in sticky traps was determined to be 0.9-3.5% of the pheromone blend. This release ratio range was reduced to 0.9-1.6% when bucket traps were used.

  12. Muon-fluorine entanglement in fluoropolymers.

    PubMed

    Lancaster, T; Pratt, F L; Blundell, S J; McKenzie, I; Assender, H E

    2009-08-26

    We present the results of muon spin relaxation measurements on the fluoropolymers polytetrafluoroethylene (PTFE), poly(vinylidene fluoride) (PVDF) and poly(vinyl fluoride) (PVF). Entanglement between the muon spin and the spins of the fluorine nuclei in the polymers allows us to identify the different muon stopping states that occur in each of these materials and provides a method of probing the local environment of the muon and the dynamics of the polymer chains.

  13. MUON COLLIDERS - IONIZATION COOLING AND SOLENOIDS.

    SciTech Connect

    PARSA,Z.

    1999-03-29

    For a muon collider, to obtain the needed luminosity, the phase space volume must be greatly reduced within the muon life time. The ionization cooling is the preferred method used to compress the phase space and reduce the emittance to obtain high luminosity muon beams. Alternating solenoid lattices has been proposed for muon colliders, where the emittance are huge. We present an overview, discuss formalism, transfer maps for solenoid magnets and beam dynamics.

  14. The MICE Muon Beam Line

    SciTech Connect

    Apollonio, Marco

    2011-10-06

    In the Muon Ionization Cooling Experiment (MICE) at RAL, muons are produced and transported in a dedicated beam line connecting the production point (target) to the cooling channel. We discuss the main features of the beamline, meant to provide muons with momenta between 140 MeV/c and 240 MeV/c and emittances up to 10 mm rad, which is accomplished by means of a diffuser. Matching procedures to the MICE cooling channel are also described. In summer 2010 we performed an intense data taking campaign to finalize the calibration of the MICE Particle Identification (PID) detectors and the understanding of the beam line, which completes the STEPI phase of MICE. We highlight the main results from these data.

  15. The MICE Muon Beam Line

    NASA Astrophysics Data System (ADS)

    Apollonio, Marco

    2011-10-01

    In the Muon Ionization Cooling Experiment (MICE) at RAL, muons are produced and transported in a dedicated beam line connecting the production point (target) to the cooling channel. We discuss the main features of the beamline, meant to provide muons with momenta between 140 MeV/c and 240 MeV/c and emittances up to 10 mm rad, which is accomplished by means of a diffuser. Matching procedures to the MICE cooling channel are also described. In summer 2010 we performed an intense data taking campaign to finalize the calibration of the MICE Particle Identification (PID) detectors and the understanding of the beam line, which completes the STEPI phase of MICE. We highlight the main results from these data.

  16. Law of Conservation of Muons

    DOE R&D Accomplishments Database

    Feinberg, G.; Weinberg, S.

    1961-02-01

    A multiplicative selection rule for mu meson-electron transitions is proposed. A "muon parity" = -1 is considered for the muon and its neutrino, while the "muon parity" for all other particles is +1. The selection rule then states that (-1) exp(no. of initial (-1) parity particles) = (-1) exp(no. of final (-1) parity particles). Several reactions that are forbidden by an additive law but allowed by the multiplicative law are suggested; these reactions include mu{sup +} .> e{sup +} + nu{sub mu} + {ovr nu}{sub e}, e{sup -} + e{sup -} .> mu{sup -} + mu{sup -}, and muonium .> antimuonium (mu{sup +} + e{sup -} .> mu{sup -} + e{sup +}). An intermediate-boson hypothesis is suggested. (T.F.H.)

  17. Muon problem in UHECR investigations

    NASA Astrophysics Data System (ADS)

    Petrukhin, A. A.; Bogdanov, A. G.; Kokoulin, R. P.

    2013-02-01

    In many UHECR experiments, some excess of muons is observed, which cannot be explained in frame of the existing theoretical models of hadron interaction. Attempts of its explanation through a heavy mass composition of PCR contradict the results of Xmax measurements. Really, the excess of muons appears already at lower energies (1016 - 1017 eV), but in this domain it may be explained by the trend to a heavier mass composition, which is in a qualitative agreement with the galactic model of CR origin. The absence of heavy nuclei at energies of the order of 1018 eV requires to consider other possibilities of the appearance of muon excess, including changes of hadron interaction model. The actuality of the considered problem is connected with plans of future experiments in UHECR physics, in which the necessity of its solution must be taken into account.

  18. Muon g - 2 and Tests of Relativity

    NASA Astrophysics Data System (ADS)

    Farley, Francis J. M.

    2015-07-01

    After a brief introduction to the muon anomalous moment a ≡ (g-2)/2, the pioneering measurements at CERN are described. This includes the CERN cyclotron experiment, the first Muon Storage Ring, the invention of the "magic energy", the second Muon Storage Ring and stringent tests of special relativity.

  19. A Highly intense DC muon source, MuSIC and muon CLFV search

    NASA Astrophysics Data System (ADS)

    Hino, Y.; Kuno, Y.; Sato, A.; Sakamoto, H.; Matsumoto, Y.; Tran, N. H.; Hashim, I. H.; Fukuda, M.; Hayashida, Y.; Ogitsu, T.; Yamamoto, A.; Yoshida, M.

    2014-08-01

    MuSIC is a new muon facility, which provides the world's highest intense muon beam with continuous time structure at Research Center of Nuclear Physics (RCNP), Osaka University. It's intensity is designed to be 108 muons per second with only 0.4 kW proton beam. Such a high intense muon beam is very important for searches of rare decay processes, for example search for the muon to electron conversion.

  20. A method to characterize in vivo tendon force-strain relationship by combining ultrasonography, motion capture and loading rates.

    PubMed

    Gerus, Pauline; Rao, Guillaume; Berton, Eric

    2011-08-11

    The ultrasonography contributes to investigate in vivo tendon force-strain relationship during isometric contraction. In previous studies, different methods are available to estimate the tendon strain, using different loading rates and models to fit the tendon force-strain relationship. This study was aimed to propose a standard method to characterize the in vivo tendon force-strain relationship. We investigated the influence on the force-strain relationship for medialis gastrocnemius (MG) of (1) one method which takes into account probe and joint movements to estimate the instantaneous tendon length, (2) models used to fit the force-strain relationship for uniaxial test (polynomial vs. Ogden), and (3) the loading rate on tendon strain. Subjects performed ramp-up contraction during isometric contractions at two different target speeds: 1.5s and minimal time with ultrasound probe fixed over the muscle-tendon junction of the MG muscle. The used method requires three markers on ultrasound probe and a marker on calcaneum to take into account all movements, and was compared to the strain estimated using ultrasound images only. The method using ultrasound image only overestimated the tendon strain from 40% of maximal force. The polynomial model showed similar fitting results than the Ogden model (R²=0.98). A loading rate effect was found on tendon strain, showing a higher strain when loading rate decreases. The characterization of tendon force-strain relationship needs to be standardized by taking into account all movements to estimate tendon strain and controlling the loading rate. The polynomial model appears to be appropriate to represent the tendon force-strain relationship.

  1. Comparative study of Gamow-Teller strength distributions in the odd-odd nucleus V50 and its impact on electron capture rates in astrophysical environments

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Sajjad, Muhammad

    2007-11-01

    Gamow-Teller (GT) strength transitions are an ideal probe for testing nuclear structure models. In addition to nuclear structure, GT transitions in nuclei directly affect the early phases of Type Ia and Type-II supernovae core collapse since the electron capture rates are partly determined by these GT transitions. In astrophysics, GT transitions provide an important input for model calculations and element formation during the explosive phase of a massive star at the end of its life-time. Recent nucleosynthesis calculations show that odd-odd and odd-A nuclei cause the largest contribution in the rate of change of lepton-to-baryon ratio. In the present manuscript, we have calculated the GT strength distributions and electron capture rates for odd-odd nucleus V50 by using the pn-QRPA theory. At present V50 is the first experimentally available odd-odd nucleus in fp-shell nuclei. We also compare our GT strength distribution with the recently measured results of a V50(d, He2)Ti50 experiment, with the earlier work of Fuller, Fowler, and Newman (referred to as FFN) and subsequently with the large-scale shell model calculations. One curious finding of the paper is that the Brink's hypothesis, usually employed in large-scale shell model calculations, is not a good approximation to use at least in the case of V50. SNe Ia model calculations performed using FFN rates result in overproduction of Ti50, and were brought to a much acceptable value by employing shell model results. It might be interesting to study how the composition of the ejecta using presently reported QRPA rates compare with the observed abundances.

  2. The KACST muon detector and its application to cosmic-ray variations studies

    NASA Astrophysics Data System (ADS)

    Maghrabi, A. H.; Al Harbi, H.; Al-Mostafa, Z. A.; Kordi, M. N.; Al-Shehri, S. M.

    2012-09-01

    A single channel cosmic ray muon detector was constructed and installed in Riyadh, central Saudi Arabia, for studying the variations in the cosmic ray (CR) muon flux. The detector has been in operation since July 2002. The recorded data correspond to muons that primarily have energies between 10 and 20 GeV. The detector will be used to continuously measure the intensity of the muon components of the cosmic rays, exploring its variations and possible correlations with environment parameters. The technical aspects of this detector will be presented. Some results obtained by the detector so far will be given. These include the modulation of the CR flux on different time scales (diurnal, 27-day, and long-term variations). Additionally, the effect of a severe dust storm on the muon count rate was investigated.

  3. Precision evaluation of the 71Ga(νe,e- ) solar neutrino capture rate from the (3He,t ) charge-exchange reaction

    NASA Astrophysics Data System (ADS)

    Frekers, D.; Adachi, T.; Akimune, H.; Alanssari, M.; Brown, B. A.; Cleveland, B. T.; Ejiri, H.; Fujita, H.; Fujita, Y.; Fujiwara, M.; Gavrin, V. N.; Harakeh, M. N.; Hatanaka, K.; Holl, M.; Iwamoto, C.; Lennarz, A.; Okamoto, A.; Okamura, H.; Suzuki, T.; Tamii, A.

    2015-03-01

    A precision measurement of the 71Ga(3He,t ) 71Ge charge-exchange reaction was performed. By using a rather complete set of theoretical form factors to describe the cross-section angular distributions over a large angular range, the Gamow-Teller strength distribution up to the effective neutron-separation energy in 71Ge was extracted. The data and the analysis constrain the 71Ga(νe,e- ) solar neutrino rate in a neutrino nonoscillation scenario. For nonoscillating neutrinos we report a solar neutrino capture rate of 122.4 ±3.4 (stat ) ±1.1 (sys ) SNU, which is lower than the presently accepted value of 132 ±18 SNU, though not in disagreement given the quoted errors.

  4. Recirculating Linear Accelerators for Future Muon Facilities

    SciTech Connect

    S.A. Bogacz, K.B.Beard, R.P. Johnson

    2010-05-01

    Neutrino Factories (NF) and Muon Colliders (MC) require rapid acceleration of short-lived muons to multi-GeV and TeV energies. A Recirculating Linear Accelerator (RLA) that uses superconducting RF structures can provide exceptionally fast and economical acceleration to the extent that the focusing range of the RLA quadrupoles allows each muon to pass several times through each high-gradient cavity. A new concept of rapidly changing the strength of the RLA focusing quadrupoles as the muons gain energy is being developed to increase the number of passes that each muon will make in the RF cavities, leading to greater cost effectiveness.

  5. Neutrino Factory and Muon Collider Fellow

    SciTech Connect

    Hanson, Gail G.; Snopak, Pavel; Bao, Yu

    2015-03-20

    Muons are fundamental particles like electrons but much more massive. Muon accelerators can provide physics opportunities similar to those of electron accelerators, but because of the larger mass muons lose less energy to radiation, allowing more compact facilities with lower operating costs. The way muon beams are produced makes them too large to fit into the vacuum chamber of a cost-effective accelerator, and the short muon lifetime means that the beams must be reduced in size rather quickly, without losing too many of the muons. This reduction in size is called "cooling." Ionization cooling is a new technique that can accomplish such cooling. Intense muon beams can then be accelerated and injected into a storage ring, where they can be used to produce neutrino beams through their decays or collided with muons of the opposite charge to produce a muon collider, similar to an electron-positron collider. We report on the research carried out at the University of California, Riverside, towards producing such muon accelerators, as part of the Muon Accelerator Program based at Fermilab. Since this research was carried out in a university environment, we were able to involve both undergraduate and graduate students.

  6. Design Concepts for Muon-Based Accelerators

    SciTech Connect

    Ryne, R. D.; Berg, J. S.; Kirk, H. G.; Palmer, R. B.; Stratkis, D.; Alexahin, Y.; Bross, A.; Gollwitzer, K.; Mokhov, N. V.; Neuffer, D.; Palmer, M. A.; Yonehara, K.; Snopok, P.; Bogacz, A.; Roberts, T. J.; Delahaye, J. -P.

    2015-05-01

    Muon-based accelerators have the potential to enable facilities at both the Intensity and the Energy Frontiers. Muon storage rings can serve as high precision neutrino sources, and a muon collider is an ideal technology for a TeV or multi-TeV collider. Progress in muon accelerator designs has advanced steadily in recent years. In regard to 6D muon cooling, detailed and realistic designs now exist that provide more than 5 order-of-magnitude emittance reduction. Furthermore, detector performance studies indicate that with suitable pixelation and timing resolution, backgrounds in the collider detectors can be significantly reduced, thus enabling high-quality physics results. Thanks to these and other advances in design & simulation of muon systems, technology development, and systems demonstrations, muon storage-ring-based neutrino sources and a muon collider appear more feasible than ever before. A muon collider is now arguably among the most compelling approaches to a multi-TeV lepton collider. This paper summarizes the current status of design concepts for muon-based accelerators for neutrino factories and a muon collider.

  7. Muon g-2 Experiment Shimming

    SciTech Connect

    Kiburg, Brendan

    2016-06-28

    The Muon g-2 experiment at Fermilab will use as its primary instrument a 52-foot-wide electromagnet that creates a precise magnetic field. In this video, Fermilab's Brendan Kiburg explains the lengthy process of finely "shimming" that magnetic field into shape.

  8. Muon g-2 Experiment Shimming

    ScienceCinema

    Kiburg, Brendan

    2016-07-12

    The Muon g-2 experiment at Fermilab will use as its primary instrument a 52-foot-wide electromagnet that creates a precise magnetic field. In this video, Fermilab's Brendan Kiburg explains the lengthy process of finely "shimming" that magnetic field into shape.

  9. Pion contamination in the MICE muon beam

    SciTech Connect

    Adams, D.; Alekou, A.; Apollonio, M.; Asfandiyarov, R.; Barber, G.; Barclay, P.; de Bari, A.; Bayes, R.; Bayliss, V.; Bertoni, R.; Blackmore, V. J.; Blondel, A.; Blot, S.; Bogomilov, M.; Bonesini, M.; Booth, C. N.; Bowring, D.; Boyd, S.; Brashaw, T. W.; Bravar, U.; Bross, A. D.; Capponi, M.; Carlisle, T.; Cecchet, G.; Charnley, C.; Chignoli, F.; Cline, D.; Cobb, J. H.; Colling, G.; Collomb, N.; Coney, L.; Cooke, P.; Courthold, M.; Cremaldi, L. M.; DeMello, A.; Dick, A.; Dobbs, A.; Dornan, P.; Drews, M.; Drielsma, F.; Filthaut, F.; Fitzpatrick, T.; Franchini, P.; Francis, V.; Fry, L.; Gallagher, A.; Gamet, R.; Gardener, R.; Gourlay, S.; Grant, A.; Greis, J. R.; Griffiths, S.; Hanlet, P.; Hansen, O. M.; Hanson, G. G.; Hart, T. L.; Hartnett, T.; Hayler, T.; Heidt, C.; Hills, M.; Hodgson, P.; Hunt, C.; Iaciofano, A.; Ishimoto, S.; Kafka, G.; Kaplan, D. M.; Karadzhov, Y.; Kim, Y. K.; Kuno, Y.; Kyberd, P.; Lagrange, J. -B.; Langlands, J.; Lau, W.; Leonova, M.; Li, D.; Lintern, A.; Littlefield, M.; Long, K.; Luo, T.; Macwaters, C.; Martlew, B.; Martyniak, J.; Mazza, R.; Middleton, S.; Moretti, A.; Moss, A.; Muir, A.; Mullacrane, I.; Nebrensky, J. J.; Neuffer, D.; Nichols, A.; Nicholson, R.; Nugent, J. C.; Oates, A.; Onel, Y.; Orestano, D.; Overton, E.; Owens, P.; Palladino, V.; Pasternak, J.; Pastore, F.; Pidcott, C.; Popovic, M.; Preece, R.; Prestemon, S.; Rajaram, D.; Ramberger, S.; Rayner, M. A.; Ricciardi, S.; Roberts, T. J.; Robinson, M.; Rogers, C.; Ronald, K.; Rubinov, P.; Rucinski, P.; Sakamato, H.; Sanders, D. A.; Santos, E.; Savidge, T.; Smith, P. J.; Snopok, P.; Soler, F. J. P.; Speirs, D.; Stanley, T.; Stokes, G.; Summers, D. J.; Tarrant, J.; Taylor, I.; Tortora, L.; Torun, Y.; Tsenov, R.; Tunnell, C. D.; Uchida, M. A.; Vankova-Kirilova, G.; Virostek, S.; Vretenar, M.; Warburton, P.; Watson, S.; White, C.; Whyte, C. G.; Wilson, A.; Winter, M.; Yang, X.; Young, A.; Zisman, M.

    2016-03-01

    Here, the international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240\\,MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less than $\\sim$1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is $f_\\pi < 1.4\\%$ at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.

  10. Pion contamination in the MICE muon beam

    NASA Astrophysics Data System (ADS)

    Adams, D.; Alekou, A.; Apollonio, M.; Asfandiyarov, R.; Barber, G.; Barclay, P.; de Bari, A.; Bayes, R.; Bayliss, V.; Bertoni, R.; Blackmore, V. J.; Blondel, A.; Blot, S.; Bogomilov, M.; Bonesini, M.; Booth, C. N.; Bowring, D.; Boyd, S.; Brashaw, T. W.; Bravar, U.; Bross, A. D.; Capponi, M.; Carlisle, T.; Cecchet, G.; Charnley, C.; Chignoli, F.; Cline, D.; Cobb, J. H.; Colling, G.; Collomb, N.; Coney, L.; Cooke, P.; Courthold, M.; Cremaldi, L. M.; DeMello, A.; Dick, A.; Dobbs, A.; Dornan, P.; Drews, M.; Drielsma, F.; Filthaut, F.; Fitzpatrick, T.; Franchini, P.; Francis, V.; Fry, L.; Gallagher, A.; Gamet, R.; Gardener, R.; Gourlay, S.; Grant, A.; Greis, J. R.; Griffiths, S.; Hanlet, P.; Hansen, O. M.; Hanson, G. G.; Hart, T. L.; Hartnett, T.; Hayler, T.; Heidt, C.; Hills, M.; Hodgson, P.; Hunt, C.; Iaciofano, A.; Ishimoto, S.; Kafka, G.; Kaplan, D. M.; Karadzhov, Y.; Kim, Y. K.; Kuno, Y.; Kyberd, P.; Lagrange, J.-B.; Langlands, J.; Lau, W.; Leonova, M.; Li, D.; Lintern, A.; Littlefield, M.; Long, K.; Luo, T.; Macwaters, C.; Martlew, B.; Martyniak, J.; Mazza, R.; Middleton, S.; Moretti, A.; Moss, A.; Muir, A.; Mullacrane, I.; Nebrensky, J. J.; Neuffer, D.; Nichols, A.; Nicholson, R.; Nugent, J. C.; Oates, A.; Onel, Y.; Orestano, D.; Overton, E.; Owens, P.; Palladino, V.; Pasternak, J.; Pastore, F.; Pidcott, C.; Popovic, M.; Preece, R.; Prestemon, S.; Rajaram, D.; Ramberger, S.; Rayner, M. A.; Ricciardi, S.; Roberts, T. J.; Robinson, M.; Rogers, C.; Ronald, K.; Rubinov, P.; Rucinski, P.; Sakamato, H.; Sanders, D. A.; Santos, E.; Savidge, T.; Smith, P. J.; Snopok, P.; Soler, F. J. P.; Speirs, D.; Stanley, T.; Stokes, G.; Summers, D. J.; Tarrant, J.; Taylor, I.; Tortora, L.; Torun, Y.; Tsenov, R.; Tunnell, C. D.; Uchida, M. A.; Vankova-Kirilova, G.; Virostek, S.; Vretenar, M.; Warburton, P.; Watson, S.; White, C.; Whyte, C. G.; Wilson, A.; Winter, M.; Yang, X.; Young, A.; Zisman, M.

    2016-03-01

    The international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240 MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less than ~1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is fπ < 1.4% at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.

  11. Cosmic muons, as messengers from the Universe

    SciTech Connect

    Brancus, I. M.; Rebel, H.

    2015-02-24

    Penetrating from the outer space into the Earth atmosphere, primary cosmic rays are producing secondary radiation by the collisions with the air target subsequently decaying in hadrons, pions, muons, electrons and photons, phenomenon called Extensive air Shower (EAS). The muons, considered as the “penetrating” component, survive the propagation to the Earth and even they are no direct messenger of the Universe, they reflect the features of the primary particles. The talk gives a description of the development of the extensive air showers generating the secondary particles, especially the muon component. Results of the muon flux and of the muon charge ratio, (the ratio between the positive and the negative muons), obtained in different laboratories and in WILLI experiment, are shown. At the end, the contribution of the muons measured in EAS to the investigation of the nature of the primary cosmic rays is emphasized in KASCADE and WILLI-EAS experiments.

  12. Improving Dengue Virus Capture Rates in Humans and Vectors in Kamphaeng Phet Province, Thailand, Using an Enhanced Spatiotemporal Surveillance Strategy

    PubMed Central

    Thomas, Stephen J.; Aldstadt, Jared; Jarman, Richard G.; Buddhari, Darunee; Yoon, In-Kyu; Richardson, Jason H.; Ponlawat, Alongkot; Iamsirithaworn, Sopon; Scott, Thomas W.; Rothman, Alan L.; Gibbons, Robert V.; Lambrechts, Louis; Endy, Timothy P.

    2015-01-01

    Dengue is of public health importance in tropical and sub-tropical regions. Dengue virus (DENV) transmission dynamics was studied in Kamphaeng Phet Province, Thailand, using an enhanced spatiotemporal surveillance of 93 hospitalized subjects with confirmed dengue (initiates) and associated cluster individuals (associates) with entomologic sampling. A total of 438 associates were enrolled from 208 houses with household members with a history of fever, located within a 200-m radius of an initiate case. Of 409 associates, 86 (21%) had laboratory-confirmed DENV infection. A total of 63 (1.8%) of the 3,565 mosquitoes collected were dengue polymerase chain reaction positive (PCR+). There was a significant relationship between spatial proximity to the initiate case and likelihood of detecting DENV from associate cases and Aedes mosquitoes. The viral detection rate from human hosts and mosquito vectors in this study was higher than previously observed by the study team in the same geographic area using different methodologies. We propose that the sampling strategy used in this study could support surveillance of DENV transmission and vector interactions. PMID:25986580

  13. Improving dengue virus capture rates in humans and vectors in Kamphaeng Phet Province, Thailand, using an enhanced spatiotemporal surveillance strategy.

    PubMed

    Thomas, Stephen J; Aldstadt, Jared; Jarman, Richard G; Buddhari, Darunee; Yoon, In-Kyu; Richardson, Jason H; Ponlawat, Alongkot; Iamsirithaworn, Sopon; Scott, Thomas W; Rothman, Alan L; Gibbons, Robert V; Lambrechts, Louis; Endy, Timothy P

    2015-07-01

    Dengue is of public health importance in tropical and sub-tropical regions. Dengue virus (DENV) transmission dynamics was studied in Kamphaeng Phet Province, Thailand, using an enhanced spatiotemporal surveillance of 93 hospitalized subjects with confirmed dengue (initiates) and associated cluster individuals (associates) with entomologic sampling. A total of 438 associates were enrolled from 208 houses with household members with a history of fever, located within a 200-m radius of an initiate case. Of 409 associates, 86 (21%) had laboratory-confirmed DENV infection. A total of 63 (1.8%) of the 3,565 mosquitoes collected were dengue polymerase chain reaction positive (PCR+). There was a significant relationship between spatial proximity to the initiate case and likelihood of detecting DENV from associate cases and Aedes mosquitoes. The viral detection rate from human hosts and mosquito vectors in this study was higher than previously observed by the study team in the same geographic area using different methodologies. We propose that the sampling strategy used in this study could support surveillance of DENV transmission and vector interactions.

  14. On collisional capture rates of irregular satellites around the gas-giant planets and the minimum mass of the solar nebula

    NASA Astrophysics Data System (ADS)

    Koch, F. Elliott; Hansen, Bradley M. S.

    2011-09-01

    We investigate the probability that an inelastic collision of planetesimals within the Hill sphere of the Jovian planets could explain the presence and orbits of observed irregular satellites. Capture of satellites via this mechanism is highly dependent on not only the mass of the protoplanetary disc, but also the shape of the planetesimal size distribution. We performed 2000 simulations for integrated time intervals ˜2 Myr and found that, given the currently accepted value for the minimum mass solar nebula and planetesimal number density based upon the Nesvorný et al. and Charnoz & Morbidelli size distribution dN˜D-3.5dD, the collision rates for the different Jovian planets range between ˜0.6 and ≳170 Myr-1 for objects with radii 1 km ≤r≤ 10 km. Additionally, we found that the probability that these collisions remove enough orbital energy to yield a bound orbit was ≲10-5 and had very little dependence on the relative size of the planetesimals. Of these collisions, the collision energy between two objects was ≳103 times the gravitational binding energy for objects with radii ˜100 km. We find that capturing irregular satellites via collisions between unbound objects can only account for ˜0.1 per cent of the observed population, hence this cannot be the sole method of producing irregular satellites.

  15. TrapTech R-Octenol Lure Does Not Improve the Capture Rates of Aedes albopictus (Diptera: Culicidae) and Other Container-Inhabiting Species in Biogents Sentinel Traps.

    PubMed

    Unlu, Isik; Faraji, Ary; Indelicato, Nicholas; Rochlin, Ilia

    2016-07-01

    Aedes albopictus (Skuse) and other container-inhabiting species have become important public health concerns due to the transmission of dengue, chikungunya, and Zika viruses. Effective surveillance is dependent on the ability to collect a sufficient number of mosquitoes for population monitoring and pathogen isolation. The Biogents Sentinel (BGS) trap supplied with a proprietary human skin lure has become the standard tool for container-inhabiting Aedes species collections worldwide. Recently, R-octenol, a single isomer of the well characterized mosquito attractant octenol, was shown to greatly improve the capture rate of some Aedes species when utilized with the Center for Disease Control and Prevention (CDC) light traps and Mosquito Magnet traps. This study evaluated the effectiveness of the TrapTech lure (TT lure), containing R-octenol, alone or in combination with the human skin lure in a BGS trap to capture Ae. albopictus and other species. BGS traps with human skin lures or a combination of the two lures collected approximately twice as many Ae. albopictus females compared to those with TT lures. Unlike previous studies, baiting BGS traps with TT lures did not result in increased diversity of mosquito species, or in higher numbers of other container-inhabiting Aedes species. Although human skin lures were clearly superior to TT R-octenol lures in BGS traps, R-octenol lures are more widely available and might still be used as an alternative lure, especially when Ae. albopictus populations are high.

  16. Low Cost, Low Power, Passive Muon Telescope For Interrogating Martian Sub-Surface

    NASA Astrophysics Data System (ADS)

    Naudet, C. J.; Tanaka, H.; Kedar, S.; Plaut, J. J.; Webb, F.

    2012-12-01

    Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays) to image the interior of geological structures in much the same way as standard X-ray radiography. Unlike gamma rays and neutrons that penetrate only a few meters of rock, muons can traverse through up to several kilometers of a geological target. Recent development and application of the technique to terrestrial volcanoes, caves, and mines have demonstrated that a low-power, passive muon detector can image deep into kilometer-scale geological structures and provide unprecedentedly crisp density profile images of their interior. Preliminary estimates of muon production on Mars indicate that the near-horizontal Martian mu-on flux, which is used for muon radiography of surface features, is at least as strong as that on Earth, making the technique suitable for geological exploration of Mars. The muon telescope represents an entirely new class of instruments for planetary exploration, providing a wholly new type of measurement for delineation of potentially habitable subsurface environments through detection of caves, sub-surface ice, and water, and for the interpretation of composition and evolutionary state of the Martian surface. Muon radiography is a proven, sim-ple, low cost, and efficient technology that could detect subsurface radiation-shielded habitable environments that would not be detectable by any other technique available today. Thanks to its low power and low data rate demands, it could be integrated as a secondary instrument on future missions with minimal impact on primary mission operations. A mission that includes a muon detector could set the stage for a future mission to directly explore subsurface habitable envi-ronments on Mars. Developing the technology now would position it favorably for a surface mission in the 2018-2024 time period to explore Martian regions with previously-identified po-tential trace gas sources

  17. Muon detection studied by pulse-height energy analysis: Novel converter arrangements.

    PubMed

    Holmlid, Leif; Olafsson, Sveinn

    2015-08-01

    Muons are conventionally measured by a plastic scintillator-photomultiplier detector. Muons from processes in ultra-dense hydrogen H(0) are detected here by a novel type of converter in front of a photomultiplier. The muon detection yield can be increased relative to that observed with a plastic scintillator by at least a factor of 100, using a converter of metal, semiconductor (Ge), or glass for interaction with the muons penetrating through the metal housing of the detector. This detection process is due to transient formation of excited nuclei by the well-known process of muon capture, giving beta decay. The main experimental results shown here are in the form of beta electron energy spectra detected directly by the photomultiplier. Events which give a high-energy tail in the energy spectra are probably due to gamma photons from the muons. Sharp and intense x-ray peaks from a muonic aluminium converter or housing material are observed. The detection conversion in glass and Ge converters has a time constant of the order of many minutes to reach the final conversion level, while the process in metal converters is stabilized faster. The time constants are not due to lifetimes of the excited nuclei or neutrons but are due to internal charging in the insulating converter material. Interaction of this charging with the high voltage in the photomultiplier is observed.

  18. Muon detection studied by pulse-height energy analysis: Novel converter arrangements

    SciTech Connect

    Holmlid, Leif; Olafsson, Sveinn

    2015-08-15

    Muons are conventionally measured by a plastic scintillator–photomultiplier detector. Muons from processes in ultra-dense hydrogen H(0) are detected here by a novel type of converter in front of a photomultiplier. The muon detection yield can be increased relative to that observed with a plastic scintillator by at least a factor of 100, using a converter of metal, semiconductor (Ge), or glass for interaction with the muons penetrating through the metal housing of the detector. This detection process is due to transient formation of excited nuclei by the well-known process of muon capture, giving beta decay. The main experimental results shown here are in the form of beta electron energy spectra detected directly by the photomultiplier. Events which give a high-energy tail in the energy spectra are probably due to gamma photons from the muons. Sharp and intense x-ray peaks from a muonic aluminium converter or housing material are observed. The detection conversion in glass and Ge converters has a time constant of the order of many minutes to reach the final conversion level, while the process in metal converters is stabilized faster. The time constants are not due to lifetimes of the excited nuclei or neutrons but are due to internal charging in the insulating converter material. Interaction of this charging with the high voltage in the photomultiplier is observed.

  19. Investigation of the Muon Pseudorapidities in EAS with the Muon Tracking Detector of the KASCADE Experiment

    NASA Astrophysics Data System (ADS)

    Zabierowski, J.; Antoni, T.; Apel, W. D.; Badea, F.; Bekk, K.; Bercuci, A.; Blümer, H.; Bozdog, H.; Brancus, I. M.; Büttner, C.; Chilingarian, A.; Daumiller, K.; Doll, P.; Engel, R.; Engler, J.; Feßler, F.; Gils, H. J.; Glasstetter, R.; Haungs, A.; Heck, D.; Hörandel, J. R.; Iwan, A.; Kampert, K-H.; Klages, H. O.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Müller, M.; Obenland, R.; Oehschläger, J.; Ostapchenko, S.; Petcu, M.; Rebel, H.; Risse, M.; Roth, M.; Schatz, G.; Schieler, H.; Scholz, J.; Thouw, T.; Ulrich, H.; van Buren, J.; Vardanyan, A.; Weindl, A.; Wochele, J.

    2003-07-01

    High angular accuracy of muon track measurements in KASCADE Muon Tracking Detector (MTD), together with the high precision in determination of the shower direction and shower core position, allow to investigate the pseudorapidity of muons in EAS using the concept of radial and tangential angles. Preliminary results of the pseudorapidity distribution of muons registered by the KASCADE experiment are presented. Mean muon pseudorapidity values at different stages of the longitudinal development of the EAS cascade are calculated using additionally the reconstructed muon production height provided by the MTD data. experimental results are compared with Monte Carlo simulations.

  20. Possible quantum diffusion of polaronic muons in Dy(2)Ti(2)O(7) spin ice.

    PubMed

    Quémerais, P; McClarty, P; Moessner, R

    2012-09-21

    We interpret recent measurements of the zero field muon relaxation rate in the magnetic pyrochlore Dy(2)Ti(2)O(7) as resulting from the quantum diffusion of muons in the material. In this scenario, the plateau observed at low temperature (< 7 K) in the relaxation rate is due to coherent tunneling of muons through a spatially disordered spin state and not to any magnetic fluctuations persisting at low temperature. Two further regimes either side of a maximum relaxation rate at T* = 50 K correspond to a crossover between tunneling and incoherent activated hopping motion of the muon. Our fit of the experimental data is compared with the case of muonium diffusion in KCl.

  1. Photonuclear and radiative-capture reaction rates for nuclear astrophysics and transmutation: 92-100Mo, 88Sr, 90Zr, and 139La

    NASA Astrophysics Data System (ADS)

    Beard, M.; Frauendorf, S.; Kämpfer, B.; Schwengner, R.; Wiescher, M.

    2012-06-01

    Experimental photoabsorption cross sections for the nuclei 92,94,96,98,100Mo, 88Sr, 90Zr, and 139La are used as an input for calculations of (γ,n), (γ,p), and (γ,α), as well as (n,γ), (p,γ), and (α,γ) cross sections and reaction rates at energies and temperatures relevant for nucleosynthesis network models and transmutation projects. The calculations are performed with the statistical-model code talys. The results are compared with those obtained by using different analytic standard parametrizations of γ-ray strength functions implemented in talys and with an energy-damped double-Lorentzian model. The radiative capture reaction cross sections are enhanced by the pygmy resonances in 88Sr, 90Zr, and 139La.

  2. Utilizing Gas Filled Cavities for the Generation of an Intense Muon Source

    SciTech Connect

    Stratakis, Diktys; Neuffer, David V.

    2015-05-01

    A key requirement for designing intense muon sources is operating rf cavities in multi-tesla magnetic fields. Recently, a proof-of-principle experiment demonstrated that an rf cavity filed with high pressure hydrogen gas could meet this goal. In this study, rigorous simulation is used to design and evaluate the performance of an intense muon source with gas filled cavities. We present a new lattice design and compare our results with conventional schemes. We detail the influence of gas pressure on the muon production rate.

  3. Utilizing gas-filled cavities for the generation of an intense muon source

    SciTech Connect

    Stratakis, Diktys; Neuffer, David V.

    2015-05-03

    A key requirement for designing intense muon sources is operating rf cavities in multi-tesla magnetic fields. Recently, a proof-of-principle experiment demonstrated that an rf cavity filed with high pressure hydrogen gas could meet this goal. In this study, rigorous simulation is used to design and evaluate the performance of an intense muon source with gas filled cavities. We present a new lattice design and compare our results with conventional schemes. We detail the influence of gas pressure on the muon production rate.

  4. Measurement of muon annual modulation and muon-induced phosphorescence in NaI(Tl) crystals with DM-Ice17

    SciTech Connect

    Cherwinka, J.; Grant, D.; Halzen, F.; Heeger, K. M.; Hsu, L.; A. J. F. Hubbard; Karle, A.; Kauer, M.; Kudryavtsev, V. A.; Lim, K. E.; Macdonald, C.; Maruyama, R. H.; Paling, S.; Pettus, W.; Pierpoint, Z. P.; Reilly, B. N.; Robinson, M.; Sandstrom, P.; N. J.C. Spooner; Telfer, S.; Yang, L.

    2016-02-01

    We report the measurement of muons and muon-induced phosphorescence in DM-Ice17, a NaI(Tl) direct detection dark matter experiment at the South Pole. Muon interactions in the crystal are identified by their observed pulse shape and large energy depositions. The measured muon rate in DM-Ice17 is 2.93±0.04 μ/crystal/day with a modulation amplitude of 12.3±1.7%, consistent with expectation. Following muon interactions, we observe long-lived phosphorescence in the NaI(Tl) crystals with a decay time of 5.5±0.5 s. The prompt energy deposited by a muon is correlated to the amount of delayed phosphorescence, the brightest of which consist of tens of millions of photons. These photons are distributed over tens of seconds with a rate and arrival timing that do not mimic a scintillation signal above 2 keVee. Furthermore, while the properties of phosphorescence vary among individual crystals, the annually modulating signal observed by DAMA cannot be accounted for by phosphorescence with the characteristics observed in DM-Ice17.

  5. Measurement of muon annual modulation and muon-induced phosphorescence in NaI(Tl) crystals with DM-Ice17

    DOE PAGES

    Cherwinka, J.; Grant, D.; Halzen, F.; ...

    2016-02-01

    We report the measurement of muons and muon-induced phosphorescence in DM-Ice17, a NaI(Tl) direct detection dark matter experiment at the South Pole. Muon interactions in the crystal are identified by their observed pulse shape and large energy depositions. The measured muon rate in DM-Ice17 is 2.93±0.04 μ/crystal/day with a modulation amplitude of 12.3±1.7%, consistent with expectation. Following muon interactions, we observe long-lived phosphorescence in the NaI(Tl) crystals with a decay time of 5.5±0.5 s. The prompt energy deposited by a muon is correlated to the amount of delayed phosphorescence, the brightest of which consist of tens of millions of photons.more » These photons are distributed over tens of seconds with a rate and arrival timing that do not mimic a scintillation signal above 2 keVee. Furthermore, while the properties of phosphorescence vary among individual crystals, the annually modulating signal observed by DAMA cannot be accounted for by phosphorescence with the characteristics observed in DM-Ice17.« less

  6. 20 years of cosmic muons research performed in IFIN-HH

    SciTech Connect

    Mitrica, Bogdan

    2012-11-20

    During the last two decades a modern direction in particle physics research has been developed in IFIN-HH Bucharest, Romania. The history started with the WILLI detector built in IFIN-HH Bucharest in collaboration with KIT Karlsruhe (formerly Forschungszentrum Karlsruhe). The detector was designed for measurements of the low energy muon charge ratio (< 1GeV) based on a delayed coincidence method, measuring the decay time of the muons stopped in the detector: the positive muons decay freely, but the negative muons are captured in the atom thus creating muonic atoms and decay depending on the nature of the host atom. In a first configuration, the WILLI detector was placed in a fixed position for measuring vertical muons. Further WILLI has been transformed in a rotatable device which allows directional measurements of muon charge ratio and muon flux. The results exhibit a pronounced azimuthal asymmetry (East-West effect) due to the different in fluence of the geomagnetic field on the trajectories of positive and negative muons in air. In parallel, flux measurement, taking into account muon events with nergies > 0.4GeV, show a diurnal modulation of the muon flux. The analysis of the muon events for energies < 0.6GeV reveals an aperiodic variation of the muon flux. A new detection system performing coincidence measurements between the WILLI calorimeter and a small array of 12 scintillators plates has been installed in IFIN-HH starting from the autumn of 2010. The aim of the system is to investigate muon charge ratio from individual EAS by using the mini-array as trigger for the WILLI calorimeter. Such experimental studies could provide detailed information on hadronic interaction models and primary cosmic ray composition at energies around 10{sup 15}eV. Simulation studies and preliminary experimental tests, regarding the performances of the mini-array, have been performed using H and Fe primaries, with energies in a range 10{sup 13}eV - 10{sup 15}eV. The results show

  7. Muon correlated background at the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Ahmad, Qazi Rushdy

    2002-10-01

    The Sudbury Neutrino Observatory (SNO) is a real time solar neutrino experiment. The detector utilizes 1,000 metric tons of heavy water to study the fundamental properties of neutrinos. The SNO detector has been designed to measure the flux and energy spectrum of electron-type solar neutrinos in addition to measuring the total flux of all active flavors of solar neutrinos. The primary objective of SNO is to resolve the Solar Neutrino Problem. The measurement of the neutron signal is critical to the success of SNO. Therefore, it is imperative that one thoroughly understands the various backgrounds to the neutron signal. Even though the rock overburden of 6,150 meter water equivalent provides a very good shield to cosmic muons, enough of them penetrate the detector to produce secondary particles, in particular neutrons. In this dissertation results from the study of through-going muons and neutron production due to muon spallation in the SNO detector has been presented. The following daily muon rate was found: RSNOm=68.9± 1.8(stat) day-1 The following muon-induced neutron rate was obtained, where Nmult is the neutron mutliplicity: Rmspn [1≤Nmult≤14] [SNO,AV] measured=(11.49±0.74) day-1kt-1 A primary component of the SNO detector is the data acquisition (DAQ) system. The author has been intricately involved in the design and implementation of the DAQ system and a detailed discussion of this system has been presented in this dissertation. The system was successfully deployed in late 1997 and acquisition of production data commenced in November of 1999. Although there have been minor changes to the DAQ system over the course of time, the system has been operating successfully since production data taking began in 1999.

  8. Observation of the muon inner bremsstrahlung at LEP1

    NASA Astrophysics Data System (ADS)

    Abdallah, J.; Abreu, P.; Adam, W.; Adzic, P.; Albrecht, T.; Alemany-Fernandez, R.; Allmendinger, T.; Allport, P. P.; Amaldi, U.; Amapane, N.; Amato, S.; Anashkin, E.; Andreazza, A.; Andringa, S.; Anjos, N.; Antilogus, P.; Apel, W.-D.; Arnoud, Y.; Ask, S.; Asman, B.; Augustin, J. E.; Augustinus, A.; Baillon, P.; Ballestrero, A.; Bambade, P.; Barbier, R.; Bardin, D.; Barker, G. J.; Baroncelli, A.; Battaglia, M.; Baubillier, M.; Becks, K.-H.; Begalli, M.; Behrmann, A.; Ben-Haim, E.; Benekos, N.; Benvenuti, A.; Berat, C.; Berggren, M.; Bertrand, D.; Besancon, M.; Besson, N.; Bloch, D.; Blom, M.; Bluj, M.; Bonesini, M.; Boonekamp, M.; Booth, P. S. L.; Borisov, G.; Botner, O.; Bouquet, B.; Bowcock, T. J. V.; Boyko, I.; Bracko, M.; Brenner, R.; Brodet, E.; Bruckman, P.; Brunet, J. M.; Buschbeck, B.; Buschmann, P.; Calvi, M.; Camporesi, T.; Canale, V.; Carena, F.; Castro, N.; Cavallo, F.; Chapkin, M.; Charpentier, Ph.; Checchia, P.; Chierici, R.; Chliapnikov, P.; Chudoba, J.; Chung, S. U.; Cieslik, K.; Collins, P.; Contri, R.; Cosme, G.; Cossutti, F.; Costa, M. J.; Crennell, D.; Cuevas, J.; D'Hondt, J.; da Silva, T.; da Silva, W.; Della Ricca, G.; de Angelis, A.; de Boer, W.; de Clercq, C.; de Lotto, B.; de Maria, N.; de Min, A.; de Paula, L.; di Ciaccio, L.; di Simone, A.; Doroba, K.; Drees, J.; Eigen, G.; Ekelof, T.; Ellert, M.; Elsing, M.; Espirito Santo, M. C.; Fanourakis, G.; Fassouliotis, D.; Feindt, M.; Fernandez, J.; Ferrer, A.; Ferro, F.; Flagmeyer, U.; Foeth, H.; Fokitis, E.; Fulda-Quenzer, F.; Fuster, J.; Gandelman, M.; Garcia, C.; Gavillet, Ph.; Gazis, E.; Gokieli, R.; Golob, B.; Gomez-Ceballos, G.; Goncalves, P.; Graziani, E.; Grosdidier, G.; Grzelak, K.; Guy, J.; Haag, C.; Hallgren, A.; Hamacher, K.; Hamilton, K.; Haug, S.; Hauler, F.; Hedberg, V.; Hennecke, M.; Herr, H.; Hoffman, J.; Holmgren, S.-O.; Holt, P. J.; Houlden, M. A.; Jackson, J. N.; Jarlskog, G.; Jarry, P.; Jeans, D.; Johansson, E. K.; Jonsson, P.; Joram, C.; Jungermann, L.; Kapusta, F.; Katsanevas, S.; Katsoufis, E.; Kernel, G.; Kersevan, B. P.; Kerzel, U.; King, B. T.; Kjaer, N. J.; Kluit, P.; Kokkinias, P.; Kourkoumelis, C.; Kouznetsov, O.; Krumstein, Z.; Kucharczyk, M.; Lamsa, J.; Leder, G.; Ledroit, F.; Leinonen, L.; Leitner, R.; Lemonne, J.; Lepeltier, V.; Lesiak, T.; Liebig, W.; Liko, D.; Lipniacka, A.; Lopes, J. H.; Lopez, J. M.; Loukas, D.; Lutz, P.; Lyons, L.; MacNaughton, J.; Malek, A.; Maltezos, S.; Mandl, F.; Marco, J.; Marco, R.; Marechal, B.; Margoni, M.; Marin, J.-C.; Mariotti, C.; Markou, A.; Martinez-Rivero, C.; Masik, J.; Mastroyiannopoulos, N.; Matorras, F.; Matteuzzi, C.; Mazzucato, F.; Mazzucato, M.; Mc Nulty, R.; Meroni, C.; Migliore, E.; Mitaroff, W.; Mjoernmark, U.; Moa, T.; Moch, M.; Moenig, K.; Monge, R.; Montenegro, J.; Moraes, D.; Moreno, S.; Morettini, P.; Mueller, U.; Muenich, K.; Mulders, M.; Mundim, L.; Murray, W.; Muryn, B.; Myatt, G.; Myklebust, T.; Nassiakou, M.; Navarria, F.; Nawrocki, K.; Nicolaidou, R.; Nikolenko, M.; Oblakowska-Mucha, A.; Obraztsov, V.; Olshevski, A.; Onofre, A.; Orava, R.; Osterberg, K.; Ouraou, A.; Oyanguren, A.; Paganoni, M.; Paiano, S.; Palacios, J. P.; Palka, H.; Papadopoulou, Th. D.; Pape, L.; Parkes, C.; Parodi, F.; Parzefall, U.; Passeri, A.; Passon, O.; Peralta, L.; Perepelitsa, V.; Perrotta, A.; Petrolini, A.; Piedra, J.; Pieri, L.; Pierre, F.; Pimenta, M.; Piotto, E.; Podobnik, T.; Poireau, V.; Pol, M. E.; Polok, G.; Pozdniakov, V.; Pukhaeva, N.; Pullia, A.; Rames, J.; Read, A.; Rebecchi, P.; Rehn, J.; Reid, D.; Reinhardt, R.; Renton, P.; Richard, F.; Ridky, J.; Rivero, M.; Rodriguez, D.; Romero, A.; Ronchese, P.; Roudeau, P.; Rovelli, T.; Ruhlmann-Kleider, V.; Ryabtchikov, D.; Sadovsky, A.; Salmi, L.; Salt, J.; Sander, C.; Savoy-Navarro, A.; Schwickerath, U.; Sekulin, R.; Siebel, M.; Sisakian, A.; Smadja, G.; Smirnova, O.; Sokolov, A.; Sopczak, A.; Sosnowski, R.; Spassov, T.; Stanitzki, M.; Stocchi, A.; Strauss, J.; Stugu, B.; Szczekowski, M.; Szeptycka, M.; Szumlak, T.; Tabarelli, T.; Tegenfeldt, F.; Timmermans, J.; Tkatchev, L.; Tobin, M.; Todorovova, S.; Tome, B.; Tonazzo, A.; Tortosa, P.; Travnicek, P.; Treille, D.; Tristram, G.; Trochimczuk, M.; Troncon, C.; Turluer, M.-L.; Tyapkin, I. A.; Tyapkin, P.; Tzamarias, S.; Uvarov, V.; Valenti, G.; van Dam, P.; van Eldik, J.; van Remortel, N.; van Vulpen, I.; Vegni, G.; Veloso, F.; Venus, W.; Verdier, P.; Verzi, V.; Vilanova, D.; Vitale, L.; Vrba, V.; Wahlen, H.; Washbrook, A. J.; Weiser, C.; Wicke, D.; Wickens, J.; Wilkinson, G.; Winter, M.; Witek, M.; Yushchenko, O.; Zalewska, A.; Zalewski, P.; Zavrtanik, D.; Zhuravlov, V.; Zimin, N. I.; Zintchenko, A.; Zupan, M.

    2008-10-01

    Muon bremsstrahlung photons converted in front of the DELPHI main tracker (TPC) in dimuon events at LEP1 were studied in two photon kinematic ranges: 0.2< E γ ≤1 GeV and transverse momentum with respect to the parent muon p T <40 MeV/ c, and 1< E γ ≤10 GeV and p T <80 MeV/ c. A good agreement of the observed photon rate with predictions from QED for the muon inner bremsstrahlung was found, contrary to the anomalous soft photon excess that has been observed recently in hadronic Z 0 decays. The obtained ratios of the observed signal to the predicted level of the muon bremsstrahlung are 1.06±0.12±0.07 in the photon energy range 0.2< E γ ≤1 GeV and 1.04±0.09±0.12 in the photon energy range 1< E γ ≤10 GeV. The bremsstrahlung dead cone is observed for the first time in the direct photon production at LEP.

  9. A Prototype Large Area Detector Module for Muon Scattering Tomography

    SciTech Connect

    Steer, C.A.; Boakes, J.; Burns, J.; Snow, S.; Stapleton, M.; Thompson, L.F.; Quillin, S.

    2015-07-01

    Abstract-Shielded special nuclear materials (SNM) are of concern as some fissile isotopes have low gamma and neutron emission rates. These materials are also easily shielded to the point where their passive emissions are comparable to background. Consequently, shielded SNM is very challenging for passive radiation detection portals which scan cargo containers. One potential solution for this is to utilise the natural cosmic ray muon background and examine how these muons scatter from materials inside the container volume, terms; the muon scattering tomography (MST) technique measures the three-dimensional localised scattering at all points within a cargo container, providing a degree of material discrimination. There is the additional benefit that the MST signal increases with the presence of more high density shielding materials, in contrast to passive radiation detection. Simulations and calculations suggest that the effectiveness of the technique is sensitive to the tracking accuracy amongst other parameters, motivating the need to develop practical detector systems that are capable of tracking cosmic ray muons. To this end, we have constructed and tested a 2 m by 2 m demonstration module based on gaseous drift chambers and triggered by a large area scintillator-based detector, which is readout by wavelength shifting fibres. We discuss its design, construction, characterisation and operational challenges. (authors)

  10. Introduction to Mini Muon Tracker

    SciTech Connect

    Borozdin, Konstantin N.

    2012-08-13

    Using a mini muon tracker developed at the Los Alamos National Laboratory we performed experiments of simple landscapes of various materials, including TNT, 9501, lead, tungsten, aluminium, and water. Most common scenes are four two inches thick step wedges of different dimensions: 12-inch x 12-inch, 12-inch x 9-inch, 12-inch x 6-inch, and 12-inch x 3-inch; and a one three inches thick hemisphere of lead with spherical hollow, and a similar full lead sphere.

  11. Muon ID at the ILC

    SciTech Connect

    Milstene, C.; Fisk, G.; Para, A.; /Fermilab

    2006-09-01

    This paper describes a new way to reconstruct and identify muons with high efficiency and high pion rejection. Since muons at the ILC are often produced with or in jets, for many of the physics channels of interest [1], an efficient algorithm to deal with the identification and separation of particles within jets is important. The algorithm at the core of the method accounts for the effects of the magnetic field and for the loss of energy by charged particles due to ionization in the detector. We have chosen to develop the analysis within the setup of one of the Linear Collider Concept Detectors adopted by the US. Within b-pair production jets, particles cover a wide range in momenta; however {approx}80% of the particles have a momentum below 30 GeV[2]. Our study, focused on bbar-b jets, is preceded by a careful analysis of single energy particles between 2 and 50 GeV. As medium energy particles are a substantial component of the jets, many of the particles lose part of their energy in the calorimeters and the solenoid coil before reaching the muon detector where they may have energy below 2 GeV. To deal with this problem we have implemented a Runge-Kutta correction of the calculated trajectory to better handle these lower energy particles. The multiple scattering and other stochastic processes, more important at lower energy, is addressed by a Kalman-filter integrated into the reconstruction algorithm. The algorithm provides a unique and powerful separation of muons from pions. The 5 Tesla magnetic field from a solenoid surrounds the hadron calorimeter and allows the reconstruction and precision.

  12. Information extraction from muon radiography data

    SciTech Connect

    Borozdin, K. N.; Asaki, T. J.; Chartrand, R.; Hengartner, N. W.; Hogan, G. E.; Morris, C. L.; Priedhorsky, W. C.; Schirato, R.C.; Schultz, L. J.; Sottile, M. J.; Vixie, K. R.; Wohlberg, B. E.; Blanpied, G.

    2004-01-01

    Scattering muon radiography was proposed recently as a technique of detection and 3-d imaging for dense high-Z objects. High-energy cosmic ray muons are deflected in matter in the process of multiple Coulomb scattering. By measuring the deflection angles we are able to reconstruct the configuration of high-Z material in the object. We discuss the methods for information extraction from muon radiography data. Tomographic methods widely used in medical images have been applied to a specific muon radiography information source. Alternative simple technique based on the counting of high-scattered muons in the voxels seems to be efficient in many simulated scenes. SVM-based classifiers and clustering algorithms may allow detection of compact high-Z object without full image reconstruction. The efficiency of muon radiography can be increased using additional informational sources, such as momentum estimation, stopping power measurement, and detection of muonic atom emission.

  13. Observation of muon intensity variations by season with the MINOS near detector

    SciTech Connect

    Adamson, P.; Anghel, I.; Aurisano, A.; 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.; Fields, T. H.; 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.; 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.; Mathis, M.; Mayer, N.; McGivern, C.; Medeiros, M. M.; Mehdiyev, R.; Meier, J. R.; Messier, M. D.; 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.; Orchanian, M.; Osprey, S.; Pahlka, R. B.; Paley, J.; Patterson, R. B.; Pawloski, G.; Perch, A.; Phan-Budd, S.; Plunkett, R. K.; Poonthottathil, N.; 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.; Tian, X.; Timmons, A.; Tognini, S. C.; Toner, R.; Torretta, D.; Urheim, J.; Vahle, P.; Viren, B.; Weber, A.; Webb, R. C.; White, C.; Whitehead, L.; Whitehead, L. H.; Wojcicki, S. G.; Zwaska, R.

    2014-07-01

    A sample of 1.53$\\times$10$^{9}$ cosmic-ray-induced single muon events has been recorded at 225 meters-water-equivalent using the MINOS Near Detector. The underground muon rate is observed to be highly correlated with the effective atmospheric temperature. The coefficient $\\alpha_{T}$, relating the change in the muon rate to the change in the vertical effective temperature, is determined to be 0.428$\\pm$0.003(stat.)$\\pm$0.059(syst.). An alternative description is provided by the weighted effective temperature, introduced to account for the differences in the temperature profile and muon flux as a function of zenith angle. Using the latter estimation of temperature, the coefficient is determined to be 0.352$\\pm$0.003(stat.)$\\pm$0.046(syst.).

  14. COMPUTATIONAL NEEDS FOR MUON ACCELERATORS.

    SciTech Connect

    BERG, J.S.

    2004-06-29

    Muon accelerators contain beam lines and components which are unlike any found in existing accelerators. Production of the muons requires targets for beams with powers which are at or beyond what has currently been achieved. Many subsystems use solenoid focusing systems where at any given point, several magnets have a significant influence. The beams that are transported can have energy spreads of {+-}30% or more. The required emittances necessitate accurate tracking of particles with angles of tenths of a radian and which are positioned almost at the edge of the beam pipe. Tracking must be done not only in vacuum, but also in materials; therefore, statistical fluctuations must also be included. Design and simulation of muon accelerators requires software which can: accurately simulate the dynamics of solid and liquid targets under proton bombardment; predict the production of particles from these targets; accurately compute magnetic fields based on either a real magnet design or a model which includes end fields; and accurately design and simulate a beam line where the transported beam satisfies the above specifications and the beam line contains non-standard, overlapping elements. The requirements for computational tools will be discussed, the capabilities of existing tools will be described and compared to what is required.

  15. Measuring the leading hadronic contribution to the muon g-2 via μ e scattering

    NASA Astrophysics Data System (ADS)

    Abbiendi, G.; Calame, C. M. Carloni; Marconi, U.; Matteuzzi, C.; Montagna, G.; Nicrosini, O.; Passera, M.; Piccinini, F.; Tenchini, R.; Trentadue, L.; Venanzoni, G.

    2017-03-01

    We propose a new experiment to measure the running of the electromagnetic coupling constant in the space-like region by scattering high-energy muons on atomic electrons of a low- Z target through the elastic process μ e → μ e. The differential cross section of this process, measured as a function of the squared momentum transfer t=q^2<0, provides direct sensitivity to the leading-order hadronic contribution to the muon anomaly a^{HLO}_{μ }. By using a muon beam of 150 GeV, with an average rate of ˜ 1.3 × 10^7 muon/s, currently available at the CERN North Area, a statistical uncertainty of ˜ 0.3% can be achieved on a^{HLO}_{μ } after two years of data taking. The direct measurement of a^{HLO}_{μ } via μ e scattering will provide an independent determination, competitive with the time-like dispersive approach, and consolidate the theoretical prediction for the muon g-2 in the Standard Model. It will allow therefore a firmer interpretation of the measurements of the future muon g-2 experiments at Fermilab and J-PARC.

  16. Fast Fourier transform to measure pressure coefficient of muons in the GRAPES-3 experiment

    NASA Astrophysics Data System (ADS)

    Mohanty, P. K.; Ahmad, S.; Antia, H. M.; Arunbabu, K. P.; Chandra, A.; Dugad, S. R.; Gupta, S. K.; Hariharan, B.; Hayashi, Y.; Jagadeesan, P.; Jain, A.; Kawakami, S.; Kojima, H.; Morris, S. D.; Nayak, P. K.; Oshima, A.; Rao, B. S.; Reddy, L. V.; Shibata, S.

    2016-06-01

    The GRAPES-3 large area (560 m2) tracking muon telescope is operating at Ooty in India since 2001. It records 4 × 109 muons of energy ≥ 1 GeV every day. These high statistics data have enabled extremely sensitive measurements of solar phenomena, including the solar anisotropies, Forbush decreases, coronal mass ejections etc. to be made. However, prior to such studies, the variation in observed muon rate caused by changes in atmospheric pressure needs to be corrected. Traditionally, the pressure coefficient (β) for the muon rate was derived from the observed data. But the influence of various solar effects makes the measurement of β somewhat difficult. In the present work, a different approach to circumvent this difficulty was used to measure β, almost independent of the solar activity. This approach exploits a small amplitude (∼1 hPa) periodic (12 h) variation of atmospheric pressure at Ooty that introduces a synchronous variation in the muon rate. By using the fast Fourier transform technique the spectral power distributions at 12 h from the atmospheric pressure, and muon rate were used to measure β. The value of pressure coefficient was found to be β =(- 0.128 ± 0.005) % hPa-1.

  17. The US Muon Accelerator Program (MAP)

    SciTech Connect

    Bross, Alan D.; /Fermilab

    2010-12-01

    The US Department of Energy Office of High Energy Physics has recently approved a Muon Accelerator Program (MAP). The primary goal of this effort is to deliver a Design Feasibility Study for a Muon Collider after a 7 year R&D program. This paper presents a brief physics motivation for, and the description of, a Muon Collider facility and then gives an overview of the program. I will then describe in some detail the primary components of the effort.

  18. Compression and extraction of stopped muons.

    PubMed

    Taqqu, D

    2006-11-10

    Efficient conversion of a standard positive muon beam into a high-quality slow muon beam is shown to be achievable by compression of a muon swarm stopped in an extended gas volume. The stopped swarm can be squeezed into a mm-size swarm flow that can be extracted into vacuum through a small opening in the stop target walls. Novel techniques of swarm compression are considered. In particular, a density gradient in crossed electric and magnetic fields is used.

  19. Materials science with muon spin rotation

    NASA Technical Reports Server (NTRS)

    1988-01-01

    During this reporting period, the focus of activity in the Materials Science with Muon Spin Rotation (MSMSR) program was muon spin rotation studies of superconducting materials, in particular the high critical temperature and heavy-fermion materials. Apart from these studies, work was continued on the analysis of muon motion in metal hydrides. Results of these experiments are described in six papers included as appendices.

  20. Magnets for Muon 6D Cooling Channels

    SciTech Connect

    Johnson, Rolland; Flanagan, Gene

    2014-09-10

    The Helical Cooling Channel (HCC), an innovative technique for six-dimensional (6D) cooling of muon beams using a continuous absorber inside superconducting magnets, has shown considerable promise based on analytic and simulation studies. The implementation of this revolutionary method of muon cooling requires high field superconducting magnets that provide superimposed solenoid, helical dipole, and helical quadrupole fields. Novel magnet design concepts are required to provide HCC magnet systems with the desired fields for 6D muon beam cooling. New designs feature simple coil configurations that produce these complex fields with the required characteristics, where new high field conductor materials are particularly advantageous. The object of the program was to develop designs and construction methods for HCC magnets and design a magnet system for a 6D muon beam cooling channel. If successful the program would develop the magnet technologies needed to create bright muon beams for many applications ranging from scientific accelerators and storage rings to beams to study material properties and new sources of energy. Examples of these applications include energy frontier muon colliders, Higgs and neutrino factories, stopping muon beams for studies of rare fundamental interactions and muon catalyzed fusion, and muon sources for cargo screening for homeland security.

  1. Capturing the Future: Direct and Indirect Probes of Neutron Capture

    SciTech Connect

    Couture, Aaron Joseph

    2016-08-31

    This report documents aspects of direct and indirect neutron capture. The importance of neutron capture rates and methods to determine them are presented. The following conclusions are drawn: direct neutron capture measurements remain a backbone of experimental study; work is being done to take increased advantage of indirect methods for neutron capture; both instrumentation and facilities are making new measurements possible; more work is needed on the nuclear theory side to understand what is needed furthest from stability.

  2. The ATLAS conditions database architecture for the Muon spectrometer

    NASA Astrophysics Data System (ADS)

    Verducci, Monica; ATLAS Muon Collaboration

    2010-04-01

    The Muon System, facing the challenge requirement of the conditions data storage, has extensively started to use the conditions database project 'COOL' as the basis for all its conditions data storage both at CERN and throughout the worldwide collaboration as decided by the ATLAS Collaboration. The management of the Muon COOL conditions database will be one of the most challenging applications for Muon System, both in terms of data volumes and rates, but also in terms of the variety of data stored. The Muon conditions database is responsible for almost all of the 'non event' data and detector quality flags storage needed for debugging of the detector operations and for performing reconstruction and analysis. The COOL database allows database applications to be written independently of the underlying database technology and ensures long term compatibility with the entire ATLAS Software. COOL implements an interval of validity database, i.e. objects stored or referenced in COOL have an associated start and end time between which they are valid, the data is stored in folders, which are themselves arranged in a hierarchical structure of folder sets. The structure is simple and mainly optimized to store and retrieve object(s) associated with a particular time. In this work, an overview of the entire Muon conditions database architecture is given, including the different sources of the data and the storage model used. In addiction the software interfaces used to access to the conditions data are described, more emphasis is given to the Offline Reconstruction framework ATHENA and the services developed to provide the conditions data to the reconstruction.

  3. A Personal Adventure in Muon-Catalyzed Fusion

    NASA Astrophysics Data System (ADS)

    Jackson, John David

    2010-03-01

    Luis Alvarez and colleagues discovered muon-catalyzed fusion of hydrogen isotopes by chance in late 1956. On sabbatical leave at Princeton University during that year, I read the first public announcement of the discovery at the end of December in that well-known scientific journal, The New York Times. A nuclear theorist by prior training, I was intrigued enough in the phenomenon to begin some calculations. I describe my work here, my interaction with Alvarez, and a summary of the surprising developments, both before and after Alvarez’s discovery. The rare proton-deuteron ( p-d) fusion events in Alvarez’s liquid-hydrogen bubble chamber occurred only because of the natural presence of a tiny amount of deuterium (heavy hydrogen). Additionally, the fusion rate, once the proton-deuteron-muon ( pdμ - ) molecular ion has been formed, is sufficiently slow that only rarely does an additional catalytic act occur. A far different situation occurs for muons stopping in pure deuterium or a deuterium-tritium ( d- t) mixture where the fusion rates are many orders of magnitude larger and the molecular-formation rates are large compared to the muon’s decay rate. The intricate interplay of atomic, molecular, and nuclear science, together with highly fortuitous accidents in the molecular dynamics and the hope of practical application, breathed life into a seeming curiosity. A small but vigorous worldwide community has explored these myriad phenomena in the past 50 years.

  4. Search for right-handed currents in muon decay

    SciTech Connect

    Jodidio, A.E.

    1986-01-01

    Limits are reported on charged right-handed currents, based on precise measurement of the endpoint e/sup +/ spectrum in ..mu../sup +/ decay. Highly polarized ..mu../sup +/ from the TRIUMF ''surface'' muon beam were stopped in high purity metal foils and liquid He targets selected to minimize depolarization effects. Decay e/sup +/ emitted within 160 mrad of the beam direction were momentum-analyzed to 0.15%. Muons were stopped within either a spin-processing transverse field (70-G or 110-G) or a spin-holding longitudinal field (0.3-T or 1.1-T). Data collected with the spin-precessing field were used for the momentum calibration of the spectrometer. The spin-held data were used to measure the relative e/sup +/ rate at the endpoint. An extrapolation was made to extract the endpoint rate opposite to the ..mu../sup +/ spin. In terms of the standard muon decay parameters this rate is given by (1-xi P/sub ..mu../delta/rho) where P/sub ..mu../ is muon polarization. The result for xi P/sub ..mu../delta was consistent with the V-A prediction of 1. It is quoted as a 90% confidence lower limit xi P/sub ..mu../delta/rho > 0.9975 since we are unable to correct for all possible sources of muon depolarization. For the model with manifest left-right symmetry and massless neutrinos the result implies 90% confidence limits m(W/sub 2/) > 432 GeV/c/sup 2/ and -0.050 < xi < 0.035, where W/sub 2/ is the predominantly right-handed boson and xi is the left-right mixing angle. With the assumption of no left-right mixing an equivalent 90% confidence upper limit of 0.025 is obtained on the absolute value of the ratio of a possible V+A amplitude to the dominant V-A amplitude in muon and pion decays. Limits are also deduced on the nu/sub ..mu..L/ mass and helicity in ..pi../sup +/ decay, non-(V-A) couplings in helicity projection form, the mass scale of composite leptons, and the branching ratio for ..-->.. e+f where f (familon) is the neutral massless Nambu-Goldstone boson associated with

  5. The D0 muon system and early results on its performance

    SciTech Connect

    Hedin, D. . Dept. of Physics)

    1992-10-01

    The D0 detector is a large, general-purpose detector designed to take full advantage of the 2 TeV energy of the Fermilab collider. The design of the experiment emphasizes accurate identification, complete angular acceptance, and precise measurement of the decay products of W and Z bosons: charged leptons (both electrons and muons), quarks and gluons, which emerge as collimated jets of particles, and noninteracting particles, such as neutrinos. The primary physics goals of D0 include searching for new phenomena, such as the top quark or particles outside the standard model, and high-precision studies of the W and Z bosons. In addition, the excellent muon identification will allow the study of b-quark production and decay. This report will describe D0's muon system, give preliminary measurements of chamber and trigger rates, and discuss muon identification.

  6. The Muon g-2 Experiment Overview and Status as of June 2016

    NASA Astrophysics Data System (ADS)

    Holzbauer, J.

    2016-11-01

    The Muon g-2 Experiment at Fermilab will measure the anomalous magnetic moment of the muon to a precision of 140 parts per billion, which is a factor of four improvement over the previous E821 measurement at Brookhaven. The experiment will also extend the search for the electric dipole moment (EDM) of the muon by approximately two orders of magnitude, with a sensitivity down to 10-21 e.cm. Both of these measurements are made by combining a precise measurement of the 1.45T storage ring magnetic field with an analysis of the modulation of the decay rate of higher-energy positrons (from anti-muons), recorded by 24 calorimeters and 3 straw tracking detectors. The recent progress in the alignment of the electrostatic quadrapole plates and the trolley rails inside the vacuum chambers, and in establishing the uniform storage ring magnetic field will be described.

  7. Using polarized muons as ultrasensitive spin labels in free radical chemistry.

    PubMed

    McKenzie, Iain; Roduner, Emil

    2009-08-01

    In a chemical sense, the positive muon is a light proton. It is obtained at the ports of accelerators in beams with a spin polarization of 100%, which makes it a highly sensitive probe of matter. The muonium atom is a light hydrogen isotope, nine times lighter than H, with a muon as its nucleus. It reacts the same way as H, and by addition to double bonds it is implemented in free radicals in which the muon serves as a fully polarized spin label. It is reviewed here how the muon can be used to obtain information about muonium and radical reaction rates, radical structure, dynamics, and local environments. It can even tell us what a fragrance molecule does in a shampoo.

  8. Observation of a level crossing in a molecular nanomagnet using implanted muons.

    PubMed

    Lancaster, T; Möller, J S; Blundell, S J; Pratt, F L; Baker, P J; Guidi, T; Timco, G A; Winpenny, R E P

    2011-06-22

    We have observed an electronic energy level crossing in a molecular nanomagnet (MNM) using muon spin relaxation. This effect, not observed previously despite several muon studies of MNM systems, provides further evidence that the spin relaxation of the implanted muon is sensitive to the dynamics of the electronic spin. Our measurements on a broken ring MNM [H(2)N(t)Bu(is)Pr][Cr(8)CdF(9)(O(2)CC(CH(3))(3))(18)], which contains eight Cr ions, show clear evidence for the S = 0 --> S = 1 transition that takes place at B(c) = 2.3 T. The crossing is observed as a resonance-like dip in the average positron asymmetry and also in the muon spin relaxation rate, which shows a sharp increase in magnitude at the transition and a peak centred within the S = 1 regime.

  9. The Muon g-2 Experiment overview and status as of June 2016

    SciTech Connect

    Holzbauer, J. L.

    2016-12-09

    The Muon g-2 Experiment at Fermilab will measure the anomalous magnetic moment of the muon to a precision of 140 parts per billion, which is a factor of four improvement over the previous E821 measurement at Brookhaven. The experiment will also extend the search for the electric dipole moment (EDM) of the muon by approximately two orders of magnitude, with a sensitivity down to 10-21 e.cm. Both of these measurements are made by combining a precise measurement of the 1.45T storage ring magnetic field with an analysis of the modulation of the decay rate of higher-energy positrons (from anti-muons), recorded by 24 calorimeters and 3 straw tracking detectors. Furthermore, the recent progress in the alignment of the electrostatic quadrapole plates and the trolley rails inside the vacuum chambers, and in establishing the uniform storage ring magnetic field will be described.

  10. The Muon g-2 Experiment overview and status as of June 2016

    DOE PAGES

    Holzbauer, J. L.

    2016-12-09

    The Muon g-2 Experiment at Fermilab will measure the anomalous magnetic moment of the muon to a precision of 140 parts per billion, which is a factor of four improvement over the previous E821 measurement at Brookhaven. The experiment will also extend the search for the electric dipole moment (EDM) of the muon by approximately two orders of magnitude, with a sensitivity down to 10-21 e.cm. Both of these measurements are made by combining a precise measurement of the 1.45T storage ring magnetic field with an analysis of the modulation of the decay rate of higher-energy positrons (from anti-muons), recordedmore » by 24 calorimeters and 3 straw tracking detectors. Furthermore, the recent progress in the alignment of the electrostatic quadrapole plates and the trolley rails inside the vacuum chambers, and in establishing the uniform storage ring magnetic field will be described.« less

  11. Using polarized muons as ultrasensitive spin labels in free radical chemistry

    NASA Astrophysics Data System (ADS)

    McKenzie, Iain; Roduner, Emil

    2009-08-01

    In a chemical sense, the positive muon is a light proton. It is obtained at the ports of accelerators in beams with a spin polarization of 100%, which makes it a highly sensitive probe of matter. The muonium atom is a light hydrogen isotope, nine times lighter than H, with a muon as its nucleus. It reacts the same way as H, and by addition to double bonds it is implemented in free radicals in which the muon serves as a fully polarized spin label. It is reviewed here how the muon can be used to obtain information about muonium and radical reaction rates, radical structure, dynamics, and local environments. It can even tell us what a fragrance molecule does in a shampoo.

  12. Real-time capture of seismic waves using high-rate multi-GNSS observations: Application to the 2015 Mw 7.8 Nepal earthquake

    NASA Astrophysics Data System (ADS)

    Geng, Tao; Xie, Xin; Fang, Rongxin; Su, Xing; Zhao, Qile; Liu, Gang; Li, Heng; Shi, Chuang; Liu, Jingnan

    2016-01-01

    The variometric approach is investigated to measure real-time seismic waves induced by the 2015 Mw 7.8 Nepal earthquake with high-rate multi-GNSS observations, especially with the contribution of newly available BDS. The velocity estimation using GPS + BDS shows an additional improvement of around 20% with respect to GPS-only solutions. We also reconstruct displacements by integrating GNSS-derived velocities after a linear trend removal (IGV). The displacement waveforms with accuracy of better than 5 cm are derived when postprocessed GPS precise point positioning results are used as ground truth, even if those stations have strong ground motions and static offsets of up to 1-2 m. GNSS-derived velocity and displacement waveforms with the variometric approach are in good agreement with results from strong motion data. We therefore conclude that it is feasible to capture real-time seismic waves with multi-GNSS observations using the IGV-enhanced variometric approach, which has critical implications for earthquake early warning, tsunami forecasting, and rapid hazard assessment.

  13. Comment on 'Time modulation of K-shell electron capture decay rates of H-like heavy ions at GSI experiments.'

    SciTech Connect

    Lipkin, H. J.; Physics; Weizmann Inst. of Science; Tel Aviv Univ.

    2010-04-16

    A Comment on the Letter by A.N. Ivanov and P. Kienle, Physical Review Letters volume 103, Issue 6, 062502 (2009). The authors of the Letter offer a Reply to experimental data at GSI, the rates of the number of daughter ions, produced by the nuclear K shell electron capture decays of the H-like heavy ions with one electron in the K shell, such as {sup 140}Pr{sup 58+}, {sup 142}Pm{sup 60+}, and {sup 122}I{sup 52+}, are modulated in time with periods T{sub EC} of the order of a few seconds, obeying an A scaling T{sub EX}=A/20 s, where A is the mass number of the mother nuclei, and with amplitudes a{sub d {sup EC}}{approx}0.21. We show that these data can be explained in terms of the interference of two massive neutrino mass eigenstates. The appearance of the interference term is due to overlap of massive neutrino mass eigenstate energies and of the wave functions of the daughter ions in two-body decay channels, caused by the energy and momentum uncertainties introduced by time differential detection of the daughter ions in GSI experiments.

  14. Polarization Effects at a Muon Collider

    SciTech Connect

    Parsa, Z.

    1998-11-01

    For Muon Colliders, Polarization will be a useful tool if high polarization is achievable with little luminosity loss. Formulation and effects of beam polarization and luminosity including polarization effects in Higgs resonance studies are discussed for improving precision measurements and Higgs resonance ''discovery'' capability e.g. at the First Muon Collider (FMC).

  15. Improving scintillation crystals using muon tomography

    SciTech Connect

    Dowell, D.H.; Fineman, B.J.; Sandorfi, A.M.

    1987-01-01

    The cosmic ray muon scanning array provides information on NaI(T1) crystals using some 65,536 trajectories, each measuring the NaI(T1) response to high energy muons. With this information, it is possible to use established computer-aided-tomography techniques to deconvolute these integrated responses and produce a detailed picture of the detector's interior.

  16. Calculation of muon transfer from muonic hydrogen to atomic oxygen

    SciTech Connect

    Dupays, Arnaud; Lepetit, Bruno; Beswick, J. Alberto; Rizzo, Carlo; Bakalov, Dimitar

    2003-06-01

    The muon-transfer probabilities between muonic hydrogen and an oxygen atom are calculated in a constrained geometry one-dimensional model for collision energies between 10{sup -6} and 10{sup 3} eV. For relative translational energies below 10{sup -1} eV, for which the de Broglie wavelength (>1 Aa) is much larger than the characteristic distance of the potential interaction ({approx}0.1 Aa), the problem corresponds to an ultracold collision. The close-coupling time-independent quantum equations are written in terms of hyperspherical coordinates and a diabatic-by-sectors basis set. The muon-transfer probabilities are qualitatively interpreted in terms of a model involving two Landau-Zener crossings together with the threshold energy dependence. Based on this analysis, a simple procedure to estimate the energy dependence of the muon-transfer rate in three dimensions is proposed. These estimated rates are discussed in the light of previous model calculations and available experimental data for this process. It is concluded that the high transfer rates at epithermal energies inferred from experiments are unlikely to be correct.

  17. BATATA: a buried muon hodoscope

    NASA Astrophysics Data System (ADS)

    Sánchez, F.; Supanitsky, A. D.; Medina-Tanco, G.; Paic, G.; Salazar, M. E. Patiño; D'Olivo, J. C.; Molina, R. Alfaro

    2009-04-01

    Muon hodoscopes have several applications, ranging from astrophysics to fundamental particle physics. In this work, we present a detector dedicated to the study, at ground level, of the main signals of cosmic-ray induced showers above 6 PeV. The whole detector is composed by a set of three parallel dual-layer scintillator planes buried at fix depths ranging from 120 g/cm2 to 600 g/cm2 and by a triangular array of water cerenkov detectors located nearby on ground.

  18. Cold fusion catalyzed by muons and electrons

    SciTech Connect

    Kulsrud, R.M.

    1990-10-01

    Two alternative methods have been suggested to produce fusion power at low temperature. The first, muon catalyzed fusion or MCF, uses muons to spontaneously catalyze fusion through the muon mesomolecule formation. Unfortunately, this method fails to generate enough fusion energy to supply the muons, by a factor of about ten. The physics of MCF is discussed, and a possible approach to increasing the number of MCF fusions generated by each muon is mentioned. The second method, which has become known as Cold Fusion,'' involves catalysis by electrons in electrolytic cells. The physics of this process, if it exists, is more mysterious than MCF. However, it now appears to be an artifact, the claims for its reality resting largely on experimental errors occurring in rather delicate experiments. However, a very low level of such fusion claimed by Jones may be real. Experiments in cold fusion will also be discussed.

  19. Reverse Emittance Exchange for Muon Colliders

    SciTech Connect

    V. Ivanov, A. Afanasev, C.M. Ankenbrandt, R.P. Johnson, G.M. Wang, S.A. Bogacz, Y.S. Derbenev

    2009-05-01

    Muon collider luminosity depends on the number of muons in the storage ring and on the transverse size of the beams in collision. Ionization cooling as it is currently envisioned will not cool the beam sizes sufficiently well to provide adequate luminosity without large muon intensities. Six-dimensional cooling schemes will reduce the longitudinal emittance of a muon beam so that smaller high frequency RF cavities can be used for later stages of cooling and for acceleration. However, the bunch length at collision energy is then shorter than needed to match the interaction region beta function. New ideas to shrink transverse beam dimensions by lengthening each bunch will help achieve high luminosity in muon colliders. Analytic expressions for the reverse emittance exchange mechanism were derived, including a new resonant method of beam focusing.

  20. Muon implantation of metallocenes: ferrocene.

    PubMed

    Jayasooriya, Upali A; Grinter, Roger; Hubbard, Penny L; Aston, Georgina M; Stride, John A; Hopkins, Gareth A; Camus, Laure; Reid, Ivan D; Cottrell, Stephen P; Cox, Stephen F J

    2007-01-01

    Muon Spin Relaxation and Avoided Level Crossing (ALC) measurements of ferrocene are reported. The main features observed are five high field resonances in the ALC spectrum at about 3.26, 2.44, 2.04, 1.19 and 1.17 T, for the low-temperature phase at 18 K. The high-temperature phase at 295 K shows that only the last feature shifted down to about 0.49 T and a muon spin relaxation peak at about 0.106 T which approaches zero field when reaching the phase transition temperature of 164 K. A model involving three muoniated radicals, two with muonium addition to the cyclopentadienyl ring and the other to the metal atom, is postulated to rationalise these observations. A theoretical treatment involving spin-orbit coupling is found to be required to understand the Fe-Mu adduct, where an interesting interplay between the ferrocene ring dynamics and the spin-orbit coupling of the unpaired electron is shown to be important. The limiting temperature above which the full effect of spin-orbit interaction is observable in the muSR spectra of ferrocene was estimated to be 584 K. Correlation time for the ring rotation dynamics of the Fe-Mu radical at this temperature is 3.2 ps. Estimated electron g values and the changes in zero-field splittings for this temperature range are also reported.

  1. The Majorana Muon Veto System

    NASA Astrophysics Data System (ADS)

    Lopez, Andrew; Majorana Demonstrator Collaboration

    2016-03-01

    Majorana Demonstrator (MJD) is one of the major efforts of the DOE NP to demonstrate very high sensitivity for the search of the neutrino less double beta decay. The ultimate goal of MJD is to prove that background levels for a tonne-scale experiment with a similar design can be as low as 1.0 count/(4 keV*t*y). One source of background is cosmic muons that can interact in the detectors or in the shielding. In order to tag cosmic muon induced background, an efficient veto system is necessary. The MJD veto system is made out of thirty two panels of 1'' plastic scintillator. Understanding the performance of MJD veto system is vital for reducing the background count. Initial data of veto system performance during the commissioning stage will be presented. This material is based upon work supported by the U.S. Dept. of Energy, Office of Science, Office of Nuclear Physics, the Particle Astrophysics and Nuclear Physics Programs of the National Science Foundation, and the Sanford Underground Research Facility.

  2. Robust estimates of environmental effects on population vital rates: an integrated capture-recapture model of seasonal brook trout growth, survival and movement in a stream network.

    PubMed

    Letcher, Benjamin H; Schueller, Paul; Bassar, Ronald D; Nislow, Keith H; Coombs, Jason A; Sakrejda, Krzysztof; Morrissey, Michael; Sigourney, Douglas B; Whiteley, Andrew R; O'Donnell, Matthew J; Dubreuil, Todd L

    2015-03-01

    Modelling the effects of environmental change on populations is a key challenge for ecologists, particularly as the pace of change increases. Currently, modelling efforts are limited by difficulties in establishing robust relationships between environmental drivers and population responses. We developed an integrated capture-recapture state-space model to estimate the effects of two key environmental drivers (stream flow and temperature) on demographic rates (body growth, movement and survival) using a long-term (11 years), high-resolution (individually tagged, sampled seasonally) data set of brook trout (Salvelinus fontinalis) from four sites in a stream network. Our integrated model provides an effective context within which to estimate environmental driver effects because it takes full advantage of data by estimating (latent) state values for missing observations, because it propagates uncertainty among model components and because it accounts for the major demographic rates and interactions that contribute to annual survival. We found that stream flow and temperature had strong effects on brook trout demography. Some effects, such as reduction in survival associated with low stream flow and high temperature during the summer season, were consistent across sites and age classes, suggesting that they may serve as robust indicators of vulnerability to environmental change. Other survival effects varied across ages, sites and seasons, indicating that flow and temperature may not be the primary drivers of survival in those cases. Flow and temperature also affected body growth rates; these responses were consistent across sites but differed dramatically between age classes and seasons. Finally, we found that tributary and mainstem sites responded differently to variation in flow and temperature. Annual survival (combination of survival and body growth across seasons) was insensitive to body growth and was most sensitive to flow (positive) and temperature (negative

  3. Reducing backgrounds in the higgs factory muon collider detector

    SciTech Connect

    Mokhov, N. V.; Tropin, I. S.

    2014-06-01

    A preliminary design of the 125-GeV Higgs Factory (HF) Muon Collider (MC) has identified an enormous background loads on the HF detector. This is related to the twelve times higher muon decay probability at HF compared to that previously studied for the 1.5-TeV MC. As a result of MARS15 optimization studies, it is shown that with a carefully designed protection system in the interaction region, in the machine-detector interface and inside the detector one can reduce the background rates to a manageable level similar to that achieved for the optimized 1.5-TeV case. The main characteristics of the HF detector background are presented for the configuration found.

  4. Muon Physics at Run-I and its upgrade plan

    NASA Astrophysics Data System (ADS)

    Benekos, Nektarios Chr.

    2015-05-01

    The Large Hadron Collider (LHC) and its multi-purpose Detector, ATLAS, has been operated successfully at record centre-of-mass energies of 7 and TeV. After this successful LHC Run-1, plans are actively advancing for a series of upgrades, culminating roughly 10 years from now in the high luminosity LHC (HL-LHC) project, delivering of order five times the LHC nominal instantaneous luminosity along with luminosity leveling. The final goal is to extend the data set from about few hundred fb-1 expected for LHC running to 3000 fb-1 by around 2030. To cope with the corresponding rate increase, the ATLAS detector needs to be upgraded. The upgrade will proceed in two steps: Phase I in the LHC shutdown 2018/19 and Phase II in 2023-25. The largest of the ATLAS Phase-1 upgrades concerns the replacement of the first muon station of the highrapidity region, the so called New Small Wheel. This configuration copes with the highest rates expected in Phase II and considerably enhances the performance of the forward muon system by adding triggering functionality to the first muon station. Prospects for the ongoing and future data taking are presented. This article presents the main muon physics results from LHC Run-1 based on a total luminosity of 30 fb^-1. Prospects for the ongoing and future data taking are also presented. We will conclude with an update of the status of the project and the steps towards a complete operational system, ready to be installed in ATLAS in 2018/19.

  5. Muon simulation codes MUSIC and MUSUN for underground physics

    NASA Astrophysics Data System (ADS)

    Kudryavtsev, V. A.

    2009-03-01

    The paper describes two Monte Carlo codes dedicated to muon simulations: MUSIC (MUon SImulation Code) and MUSUN (MUon Simulations UNderground). MUSIC is a package for muon transport through matter. It is particularly useful for propagating muons through large thickness of rock or water, for instance from the surface down to underground/underwater laboratory. MUSUN is designed to use the results of muon transport through rock/water to generate muons in or around underground laboratory taking into account their energy spectrum and angular distribution.

  6. Calibration Software for the Muon Detectors at CDF

    NASA Astrophysics Data System (ADS)

    Lannon, Kevin

    2001-04-01

    The muon detector system at CDF consists of the following subsystems: Central Muon Detector (CMU), the Central Muon Upgrade (CMP), the Central Muon Extension (CMX), and the Intermediate Muon Detector (IMU). Each subsystem is a collection of drift chambers and all but the CMU also incorporate scintillation counters for trigger and timing purposes. The muon calibration system performs diagnostics and calibrations on the above systems. We will describe the software that controls the muon calibration system. This software takes advantage of the existing CDF DAQ infrastructure to handle communication between a Java client containing the user interface and the VME crates where the calibration hardware resides.

  7. CONCEPTUAL DESIGN REPORT FOR A FAST MUON TRIGGER

    SciTech Connect

    OBRIEN,E.; BASYE, A.; ISENHOWER, D.; JUMPER, D.; SPARKS, N.; TOWELL, R.; WATTS, C.; WOOD, J.; WRIGHT, R.; HAGGERTY, J.; LYNCH, D.; BARISH, K.; EYSER, K.O.; SETO, R.; HU, S.; LI, X.; ZHOU, S.; GLENN, A.; KINNEY, E.; KIRILUK, K.; NAGLE, J.; CHI, C.Y.; SIPPACH, W.; ZAJC. W.; BUTLER, C.; HE, X.; OAKLEY, C.; YING, J.; BLACKBURN, J.; CHIU, M.; PERDEKAMP, M.G.; KIM, Y.J.; KOSTER, J.; LAYTON, D.; MAKINS, N.; MEREDITH, B.; NORTHACKER, D.; PENG, J.-C.; SEIDL, R.; THORSLAND, E.; WADHAMS, S.; WILLIAMSON, S.; YANG, R.; HILL, J.; KEMPEL, T.; LAJOIE, J.; SLEEGE, G.; VALE, C.; WEI, F.; SAITO, N.; HONG, B.; KIM, B.; LEE, K.; LEE, K.S.; PARK, S.; SIM, K.-S.; AOKI, K.; DAIRAKU, S.; IMAI, K.; KARATSU, K.; MURAKAMI, T.; SATO, A.; SENZAKA, K.; SHOJI, K.; TANIDA, K.; BROOKS, M.; LEITCH, M.; ADAMS, J.; CARINGI, A.; FADEM, B.; IDE, J.; LICHTENWALNER, P.; FIELDS, D.; MAO, Y.; HAN, R.; BUNCE, G.; XIE, W.; FUKAO, Y.; TAKETANI, A.; KURITA, K.; MURATA, J.

    2007-08-01

    This document is a Conceptual Design Report for a fast muon trigger for the PHENIX experiment that will enable the study of flavor separated quark and anti-quark spin polarizations in the proton. A powerful way of measuring these polarizations is via single spin asymmetries for W boson production in polarized proton-proton reactions. The measurement is done by tagging W{sup +} and W{sup -} via their decay into high transverse momentum leptons in the forward directions. The PHENIX experiment is capable of measuring high momentum muons at forward rapidity, but the current online trigger does not have sufficient rejection to sample the rare leptons fromW decay at the highest luminosities at the Relativistic Heavy Ion Collider (RHIC). This Report details the goals, design, R&D, and schedule for building new detectors and trigger electronics to use the full RHIC luminosity to make this critical measurement. The idea for W boson measurements in polarized proton-proton collisions at RHIC was first suggested by Jacques Soffer and Claude Bourrely in 1995. This prompted the RIKEN institute in Japan to supply funds to build a second muon arm for PHENIX (south muon arm). The existence of both a north and south muon arm makes it possible to utilize a Z{sup 0} sample to study and control systematic uncertainties which arise in the reconstruction of high momentum muons. This document has its origins in recommendations made by a NSAC Subcommittee that reviewed the U.S. Heavy Ion Physics Program in June 2004. Part of their Recommendation 1 was to 'Invest in near-term detector upgrades of the two large experiments, PHENIX and STAR'. In Recommendation 2 the subcommittee stated '- detector improvements proceed at a rate that allows a timely determination of the flavor dependence of the quark-antiquark sea polarization through W-asymmetry measurements' as we are proposing here. On September 13, 2004 DOE requested from BNL a report articulating a research plan for the RHIC spin physics

  8. Pion contamination in the MICE muon beam

    DOE PAGES

    Adams, D.; Alekou, A.; Apollonio, M.; ...

    2016-03-01

    Here, the international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240\\,MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less thanmore » $$\\sim$$1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is $$f_\\pi < 1.4\\%$$ at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.« less

  9. Calibration Hardware for the Muon Detectors at CDF

    NASA Astrophysics Data System (ADS)

    Vickey, Trevor

    2001-04-01

    The muon detector system at CDF consists of the following subsystems: Central Muon Detector (CMU), the Central Muon Upgrade (CMP), the Central Muon Extension (CMX), and the Intermediate Muon Detector (IMU). Each subsystem is a collection of drift chambers and all but the CMU also incorporate scintillation counters for trigger and timing purposes. We will describe the muon calibration system hardware, which performs diagnostics and calibrations on the above detectors. The muon calibration system injects charge into each channel of the CDF muon detectors to generate a signal similar to that of a muon traversing the chamber. Reading this pulse out with the data acquisition system allows us to spot problems with the muon system electronics as well as to calibrate detector timing and response to different amounts of charge.

  10. Upgrade of the ALICE muon trigger electronics

    NASA Astrophysics Data System (ADS)

    Dupieux, P.; Joly, B.; Jouve, F.; Manen, S.; Vandaële, R.

    2014-09-01

    The ALICE muon trigger is a large scale detector based on single gap bakelite RPCs. An upgrade of the electronics is needed in order to withstand the increase of luminosity after the LHC Long Shutdown-2 in 2018-2019. The detector will be read out at the minimum bias rate of 100 kHz in Pb-Pb collisions (including a safety factor of 2), two orders of magnitude above the present design. For the most exposed RPCs and in the present conditions of operation, the total integrated charge could be as high as 100 mC/cm2 with rates up to 100 Hz/cm2, which is above the present limit for safe operation. In order to overcome these limitations, upgrade projects of the Front-End (FE) and Readout Electronics are scheduled. The readout upgrade at high rate with low dead time requires changing most of the present electronics. It involves a new design for the 234 Local cards receiving the LVDS signals from the FE electronics and the 16 Regional concentrator cards. The readout chain is completed by a single Common Readout Unit developed for most ALICE sub-detectors. The new architecture of the muon trigger readout will be briefly presented. The present FE electronics, designed for the streamer mode, must be replaced to prevent ageing of the RPCs in the future operating conditions. The new FE called FEERIC (for Front-End Electronics Rapid Integrated Circuit) will have to perform amplification of the analog input signals. This will allow for RPC operation in a low-gain avalanche mode, with a much smaller charge deposit (factor 3-5) in the detector as compared to the present conditions. The purpose is to discriminate RPC signals with a charge threshold around 100 fC, in both polarities, and with a time jitter below 1 ns. We will describe the FE card and FEERIC ASIC features and first prototype performance, report on test results obtained on a cosmic test bench and discuss ongoing developments.

  11. Imaging Fukushima Daiichi reactors with muons

    SciTech Connect

    Miyadera, Haruo; Borozdin, Konstantin N.; Greene, Steve J.; Milner, Edward C.; Morris, Christopher L.; Lukic, Zarija; Masuda, Koji; Perry, John O.

    2013-05-15

    A study of imaging the Fukushima Daiichi reactors with cosmic-ray muons to assess the damage to the reactors is presented. Muon scattering imaging has high sensitivity for detecting uranium fuel and debris even through thick concrete walls and a reactor pressure vessel. Technical demonstrations using a reactor mockup, detector radiation test at Fukushima Daiichi, and simulation studies have been carried out. These studies establish feasibility for the reactor imaging. A few months of measurement will reveal the spatial distribution of the reactor fuel. The muon scattering technique would be the best and probably the only way for Fukushima Daiichi to make this determination in the near future.

  12. The University of Texas Maya Muon Project

    SciTech Connect

    Schwitters, Roy

    2007-05-09

    Plans to explore the ruin of a Maya Pyramid in Belize using cosmic ray muon tomography will be described. Muon tomography was pioneered by Luis Alvarez in the 1960's to explore the Second Pyramid of Chephren in Egypt. Improvements in detector technology since the Alvarez experiment suggest that muon tomography may be a practical method for exploring and monitoring relatively large underground volumes when exposure times of order months are acceptable. A prototype detector based on Fermilab/MINOS scintillator strip/WLS fiber technology has been built and is being tested at UT Austin. Initial results using the detector will be discussed.

  13. Atmospheric muons and neutrinos, and the neutrino-induced muon flux underground

    NASA Technical Reports Server (NTRS)

    Liland, A.

    1985-01-01

    The diffusion equation for neutrino-induced cosmic ray muons underground was solved. The neutrino-induced muon flux and charge ratio underground have been calculated. The calculated horizontal neutrino-induced muon flux in the energy range 0.1 - 10000 GeV is in agreement with the measured horizontal flux. The calculated vertical flux above 2 GeV is in agreement with the measured vertical flux. The average charge ratio of neutrino-induced muons underground was found to be mu+/mu- = 0.40.

  14. Feasibility study of heavy-ion beams and compound target materials for muon production

    NASA Astrophysics Data System (ADS)

    Sohn, Jae Bum; Lee, Ju Hahn; Kim, Gi Dong; Kim, Yong Kyun

    2015-10-01

    We have investigated the feasibility of using compound materials as targets for muon production by virtue of simulations using a GEANT4 toolkit. A graphite material and two thermostable compound materials, beryllium oxide (BeO) and boron carbide (B4C), were considered as muon production targets, and their muon production rates for a 600-MeV proton beam were calculated and compared. For the thermal analysis, the total heat deposited on the targets by the proton beams and the secondary particles was calculated with the MCNPX code; then, the temperature distribution of target was derived from the calculated heat by using the ANSYS code with consideration of heat transfer mechanisms such as thermal conduction and thermal radiation. In addition, we have investigated whether the heavy-ion beams can be utilized for muon production. For various beam species such as 3He2, 4He, 7Li, 10B and 12C, their muon production rates were calculated and compared with the rates experimentally-obtained for a proton beam.

  15. Intense muon beams and neutrino factories

    SciTech Connect

    Parsa, Z.

    2000-10-05

    High intensity muon sources are needed in exploring neutrino factories, lepton flavor violating muon processes, and lower energy experiments as the stepping phase towards building higher energy {mu}{sup +}{mu}{sup {minus}} colliders. We present a brief overview, sketch of a neutrino source, and an example of a muon storage ring at BNL with detector(s) at Fermilab, Sudan, etc. Physics with low energy neutrino beams based on muon storage rings ({mu}SR) and conventional Horn Facilities are described and compared. CP violation Asymmetries and a new Statistical Figure of Merit to be used for comparison is given. Improvements in the sensitivity of low energy experiments to study Flavor changing neutral currents are also included.

  16. A search for flaring very-high-energy cosmic γ-ray sources with the L3+C muon spectrometer

    NASA Astrophysics Data System (ADS)

    L3 Collaboration; Adriani, O.; Aguilar-Benitez, M.; van den Akker, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M. G.; Anderhub, H.; Andreev, V. P.; Anselmo, F.; Arefiev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Bähr, J.; Baldew, S. V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillère, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J. J.; Blyth, S. C.; Bobbink, G. J.; Böhm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J. G.; Brochu, F.; Burger, J. D.; Burger, W. J.; Cai, X. D.; Capell, M.; Romeo, G. Cara; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y. H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chiarusi, T.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de La Cruz, B.; Cucciarelli, S.; de Asmundis, R.; Déglon, P.; Debreczeni, J.; Degré, A.; Dehmelt, K.; Deiters, K.; Della Volpe, D.; Delmeire, E.; Denes, P.; Denotaristefani, F.; de Salvo, A.; Diemoz, M.; Dierckxsens, M.; Ding, L. K.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M. T.; Duchesneau, D.; Duda, M.; Duran, I.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Extermann, P.; Faber, G.; Falagan, M. A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, P. H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Yu.; Ganguli, S. N.; Garcia-Abia, P.; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z. F.; Grabosch, H. J.; Grenier, G.; Grimm, O.; Groenstege, H.; Gruenewald, M. W.; Guida, M.; Guo, Y. N.; Gupta, S. K.; Gupta, V. K.; Gurtu, A.; Gutay, L. J.; Haas, D.; Haller, Ch.; Hatzifotiadou, D.; Hayashi, Y.; He, Z. X.; Hebbeker, T.; Hervé, A.; Hirschfelder, J.; Hofer, H.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S. R.; Huo, A. X.; Ito, N.; Jin, B. N.; Jindal, P.; Jing, C. L.; Jones, L. W.; de Jong, P.; Josa-Mutuberría, I.; Kantserov, V.; Kaur, M.; Kawakami, S.; Kienzle-Focacci, M. N.; Kim, J. K.; Kirkby, J.; Kittel, W.; Klimentov, A.; König, A. C.; Kok, E.; Korn, A.; Kopal, M.; Koutsenko, V.; Kräber, M.; Kuang, H. H.; Kraemer, R. W.; Krüger, A.; Kuijpers, J.; Kunin, A.; de Guevara, P. Ladron; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Coultre, P. Le; Goff, J. M. Le; Lei, Y.; Leich, H.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Li, L.; Li, Z. C.; Likhoded, S.; Lin, C. H.; Lin, W. T.; Linde, F. L.; Lista, L.; Liu, Z. A.; Lohmann, W.; Longo, E.; Lu, Y. S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W. G.; Ma, X. H.; Ma, Y. Q.; Malgeri, L.; Malinin, A.; Maña, C.; Mans, J.; Martin, J. P.; Marzano, F.; Mazumdar, K.; McNeil, R. R.; Mele, S.; Meng, X. W.; Merola, L.; Meschini, M.; Metzger, W. J.; Mihul, A.; van Mil, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G. B.; Monteleoni, B.; Muanza, G. S.; Muijs, A. J. M.; Musicar, B.; Musy, M.; Nagy, S.; Nahnhauer, R.; Naumov, V. A.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Nowak, H.; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Parriaud, J.-F.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pieri, M.; Pioppi, M.; Piroué, P. A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofiev, D.; Quartieri, J.; Qing, C. R.; Rahal-Callot, G.; Rahaman, M. A.; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P. G.; Ranieri, R.; Raspereza, A.; Ravindran, K. C.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Rewiersma, P.; Riemann, S.; Riles, K.; Roe, B. P.; Rojkov, A.; Romero, L.; Rosca, A.; Rosemann, C.; Rosenbleck, C.; Rosier-Lees, S.; Roth, S.; Rubio, J. A.; Ruggiero, G.; Rykaczewski, H.; Saidi, R.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schäfer, C.; Schegelsky, V.; Schmitt, V.; Schoeneich, B.; Schopper, H.; Schotanus, D. J.; Sciacca, C.; Servoli, L.; Shen, C. Q.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D. P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sulanke, H.; Sultanov, G.; Sun, L. Z.; Sushkov, S.; Suter, H.; Swain, J. D.; Szillasi, Z.; Tang, X. W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, C.; Ting, Samuel C. C.; Ting, S. M.; Tonwar, S. C.; Tóth, J.; Trowitzsch, G.; Tully, C.; Tung, K. L.; Ulbricht, J.; Unger, M.; Valente, E.; Verkooijen, H.; van de Walle, R. T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A. A.; Wadhwa, M.; Wang, R. G.; Wang, Q.; Wang, X. L.; Wang, X. W.; Wang, Z. M.; Weber, M.; van Wijk, R.; Wijnen, T. A. M.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Y. P.; Xu, J. S.; Xu, Z. Z.; Yang, B. Z.; Yang, C. G.; Yang, H. J.; Yang, M.; Yang, X. F.; Yao, Z. G.; Yeh, S. C.; Yu, Z. Q.; Zalite, An.; Zalite, Yu.; Zhang, C.; Zhang, F.; Zhang, J.; Zhang, S.; Zhang, Z. P.; Zhao, J.; Zhou, S. J.; Zhu, G. Y.; Zhu, R. Y.; Zhu, Q. Q.; Zhuang, H. L.; Zichichi, A.; Zimmermann, B.; Zöller, M.; Zwart, A. N. M.

    2006-06-01

    The L3+C muon detector at the CERN electron positron collider, LEP, is used for the detection of very-high-energy cosmic γ-ray sources through the observation of muons of energies above 20, 30, 50 and 100 GeV. Daily or monthly excesses in the rate of single-muon events pointing to some particular direction in the sky are searched for. The periods from mid July to November 1999, and April to November 2000 are considered. Special attention is also given to a selection of known γ-ray sources. No statistically significant excess is observed for any direction or any particular source.

  17. Motivations for muon radiography of active volcanoes

    NASA Astrophysics Data System (ADS)

    Macedonio, G.; Martini, M.

    2010-02-01

    Muon radiography represents an innovative tool for investigating the interior of active volcanoes. This method integrates the conventional geophysical techniques and provides an independent way to estimate the density of the volcano structure and reveal the presence of magma conduits. The experience from the pioneer experiments performed at Mt. Asama, Mt. West Iwate, and Showa-Shinzan (Japan) are very encouraging. Muon radiography could be applied, in principle, at any stratovolcano. Here we focus our attention on Vesuvius and Stromboli (Italy).

  18. Preparations for Muon Experiments at Fermilab

    SciTech Connect

    Syphers, M.J.; Popovic, M.; Prebys, E.; Ankenbrandt, C.; /Muons Inc., Batavia

    2009-05-01

    The use of existing Fermilab facilities to provide beams for two muon experiments--the Muon to Electron Conversion Experiment (Mu2e) and the New g-2 Experiment--is under consideration. Plans are being pursued to perform these experiments following the completion of the Tevatron Collider Run II, utilizing the beam lines and storage rings used today for antiproton accumulation without considerable reconfiguration.

  19. A Low-cost, Portable, Ruggedized Cosmic Muon Detector Prototype for Geological Applications

    NASA Astrophysics Data System (ADS)

    Aguayo Navarrete, E.; Bonneville, A.

    2012-12-01

    , and other contributing factors such as altitude, magnetic field rigidity and time of the year. There has been extensive work on characterizing the cosmic ray showers and this work uses one of such parameterizations to model the cosmic muon flux. Monte Carlo simulations can model the passage of particles through matter, among them high energy muons going through Earth's subsurface. The first underground measurements carried out with the prototype are also presented. The μ-Witness detector collected measurements at Pacific Northwest National Laboratory, inside, outside, and in the shallow underground lab, which has a depth of ~30 meters water equivalent (mwe). The μ-Witness count rate was 2.51 ± 0.04 muons/s, 2.61 ± 0.05 muons/s, and 0.40 ± 0.01 muons/s inside, outside and in the underground lab, respectively. Indoor measurements were expected to be lower than outdoors, as the laboratory overhead serves as overburden, and was estimated to be about 2 mwe. From these measurements, assuming an inverse linear attenuation, we can infer the μ-Witness density sensitivity to be -0.0752 count/s*mwe. This figure will aid in the design of a large detector system for field-scale deployment at the ground surface and in boreholes.

  20. Target and collection optimization for muon colliders

    SciTech Connect

    Mokhov, N.V.; Noble, R.J.; Van Ginneken, A.

    1996-01-10

    To achieve adequate luminosity in a muon collider it is necessary to produce and collect large numbers of muons. The basic method used in this paper follows closely a proposed scheme which starts with a proton beam impinging on a thick target ({approximately} one interaction length) followed by a long solenoid which collects muons resulting mainly from pion decay. Production and collection of pions and their decay muons must be optimized while keeping in mind limitations of target integrity and of the technology of magnets and cavities. Results of extensive simulations for 8 GeV protons on various targets and with various collection schemes are reported. Besides muon yields results include-energy deposition in target and solenoid to address cooling requirements for these systems. Target composition, diameter, and length are varied in this study as well as the configuration and field strengths of the solenoid channel. A curved solenoid field is introduced to separate positive and negative pions within a few meters of the target. This permits each to be placed in separate RF buckets for acceleration which effectively doubles the number of muons per bunch available for collisions and increases the luminosity fourfold.

  1. The MICE Demonstration of Muon Ionization Cooling

    SciTech Connect

    Lagrange, Jean-Baptiste; Hunt, Christopher; Palladino, Vittorio; Pasternak, Jaroslaw

    2016-06-01

    Muon beams of low emittance provide the basis for the intense, well-characterised neutrino beams necessary to elucidate the physics of flavour at the Neutrino Factory and to provide lepton-antilepton collisions up to several TeV at the Muon Collider. The international Muon Ionization Cooling Experiment (MICE) will demonstrate muon ionization cooling, the technique proposed to reduce the phase-space volume occupied by the muon beam at such facilities. In an ionization-cooling channel, the muon beam traverses a material (the absorber) loosing energy, which is replaced using RF cavities. The combined effect is to reduce the transverse emittance of the beam (transverse cooling). The configuration of MICE required to deliver the demonstration of ionization cooling is being prepared in parallel to the execution of a programme designed to measure the cooling properties of liquid-hydrogen and lithium hydride. The design of the cooling-demonstration experiment will be presented together with a summary of the performance of each of its components and the cooling performance of the experiment.

  2. A Treatise on High Energy Muons in the IMB Detector

    NASA Astrophysics Data System (ADS)

    McGrath, Gary G.

    1993-01-01

    The Irvine-Michigan-Brookhaven proton decay detector records upward-going muon data at a rate of ~ 0.5 mu/day and downward-going muon data at a rate of 2.7 mu/s. After separating the upward-going data from the downward-going data, both data sets are examined for consistency with expectation and searched for physical effects. The upward-going muon data is used to search for numu rightarrow nue and nu mu rightarrow nu tau neutrino oscillation effects that are consistent with the parameters suggested by the atmospheric neutrino flavor anomaly that is found in the contained data. Three different techniques provide the search, but uncover no evidence. Hence, the upward -going data limits the preferred parameter space for both types of oscillations. For nu_μ rightarrow nu_{e } oscillations, the 90% C.L. limits are sin ^2 2theta >= 0.38 for large delta m^2 and delta m^2 >= 1.8 times 10^{-2} at large mixing angles, while the limits for nu_mu rightarrow nutau oscillations are sin^2 2 theta >= 0.42 for large delta m^2 and delta m^2 >= 1.7 times 10^{ -3} at large mixing angles. Although the upward -going data remains consistent with the neutrino oscillation hypothesis, it greatly limits the possible parameters. In addition to the neutrino oscillation analysis, the downward-going muon data is used to search for point sources and to study the origins of underground muons. Although the testing of 13 sources chosen a priori uncovered no candidates, two features stand out in these data: at least two possible point sources and a large scale anisotropy. A survey of the entire sky finds two excesses at IMBm1 = (alpha ~ 164^ circ, delta ~ 53^circ) and IMBm2 = ( alpha ~ 106^circ , delta ~ 68 ^circ), with random chance probabilities (including trials penalties) of p = 2.0 times 10^{-5} and p = 7.9 times 10^{ -4} respectively, although neither direction is associated with any popular nu or gamma-ray sources. In addition, there is an anisotropy in the data favoring the alpha = 270^circ

  3. Status and future prospects of the Muon Drift Tubes System of CMS

    NASA Astrophysics Data System (ADS)

    Masetti, G.

    2017-01-01

    A key component of the CMS (Compact Muon Solenoid) experiment is its muon system. The tracking and triggering of muons in the central part relies on Drift Tube (DT) chambers. In 2013 and 2014 a number of improvements and upgrades were implemented, in particular concerning the readout and trigger electronics. The increase of luminosity expected by LHC will impose several constraints for rate reduction while maintaining high efficiency in the CMS Level 1 trigger system. In order to exploit the muon detector redundancy, a new trigger system has been designed. The TwinMux system is the early layer of the muon barrel region that combines the primitives information from different subdetectors: DT, Resistive Plate Chambers (RPC) and Outer Hadron Calorimeter (HO). Regarding the long term operation of the DT system, in order to cope with up to a factor 2 nominal LHC luminosity, several improvements will be implemented. The in-chamber local electronics will be modified to cope with the new rate and radiation environment. This paper will present, along with the main system improvements implemented in the system, the first performance results from data collected at 13 TeV center-of-mass energy during 2016, confirming the satisfactory operation of both DT performance and the TwinMux system. A review of the present status and plans for the DT system upgrades will be also described.

  4. Construction and test of new precision drift-tube chambers for the ATLAS muon spectrometer

    NASA Astrophysics Data System (ADS)

    Kroha, H.; Kortner, O.; Schmidt-Sommerfeld, K.; Takasugi, E.

    2017-02-01

    ATLAS muon detector upgrades aim for increased acceptance for muon triggering and precision tracking and for improved rate capability of the muon chambers in the high-background regions of the detector with increasing LHC luminosity. The small-diameter Muon Drift Tube (sMDT) chambers have been developed for these purposes. With half of the drift-tube diameter of the MDT chambers and otherwise unchanged operating parameters, sMDT chambers share the advantages of the MDTs, but have an order of magnitude higher rate capability and can be installed in detector regions where MDT chambers do not fit in. The chamber assembly methods have been optimized for mass production, minimizing construction time and personnel. Sense wire positioning accuracies of 5 μm have been achieved in serial production for large-size chambers comprising several hundred drift tubes. The construction of new sMDT chambers for installation in the 2016/17 winter shutdown of the LHC and the design of sMDT chambers in combination with new RPC trigger chambers for replacement of the inner layer of the barrel muon spectrometer are in progress.

  5. Preliminary limits on the flux of muon neutrinos from extraterrestrial point sources

    SciTech Connect

    Bionta, R.M.; Blewitt, G.; Bratton, C.B.; Casper, D.; Cortez, B.G.; Chrysicopoulou, P.; Claus, R.; Dye, S.T.; Errede, S.; Foster, G.W.

    1985-07-03

    We present the arrival directions of 117 upward-going muon events collected with the IMB proton lifetime detector during 317 days of live detector operation. The rate of upward-going muons observed in our detector was found to be consistent with the rate expected from atmospheric neutrino production. The upper limit on the total flux of extraterrestrial neutrinos >1 GeV is <0.06 neutrinos/cm/sup 2/-sec. Using our data and a Monte Carlo simulation of high energy muon production in the earth surrounding the detector, we place limits on the flux of neutrinos from a point source in the Vela X-2 system of <0.009 neutrinos/cm/sup 2/-sec with E > 1 GeV. 6 refs., 5 figs.

  6. Mercury Handling for the Target System for a Muon Collider

    SciTech Connect

    Graves, Van B; Mcdonald, K; Kirk, H.; Weggel, Robert; Souchlas, Nicholas; Sayed, H; Ding, X

    2012-01-01

    The baseline target concept for a Muon Collider or Neutrino Factory is a free-stream mercury jet being impacted by an 8-GeV proton beam. The target is located within a 20-T magnetic field, which captures the generated pions that are conducted to a downstream decay channel. Both the mercury and the proton beam are introduced at slight downward angles to the magnetic axis. A pool of mercury serves as a receiving reservoir for the mercury and a dump for the unexpended proton beam. The impact energy of the remaining beam and jet are substantial, and it is required that splashes and waves be controlled in order to minimize the potential for interference of pion production at the target. Design issues discussed in this paper include the nozzle, splash mitigation in the mercury pool, the mercury containment vessel, and the mercury recirculation system.

  7. Phase Rotation of Muon Beams for Producing Intense Low-Energy Muon Beams

    SciTech Connect

    Neuffer, D.; Bao, Y.; Hansen, G.

    2016-01-01

    Low-energy muon beams are useful for rare decay searches, which provide access to new physics that cannot be addressed at high-energy colliders. However, muons are produced within a broad energy spread unmatched to the low-energy required. In this paper we outline a phase rotation method to significantly increase the intensity of low-energy muons. The muons are produced from a short pulsed proton driver, and develop a time-momentum correlation in a drift space following production. A series of rf cavities is used to bunch the muons and phase-energy rotate the bunches to a momentum of around 100 MeV/c. Then another group of rf cavities is used to decelerate the muon bunches to low-energy. This obtains ~0.1 muon per 8 GeV proton, which is significantly higher than currently planned Mu2e experiments, and would enable a next generation of rare decay searches, and other intense muon beam applications.

  8. Modular detector for deep underwater registration of muons and muon groups

    NASA Technical Reports Server (NTRS)

    Demianov, A. I.; Sarycheva, L. I.; Sinyov, N. B.; Varadanyan, I. N.; Yershov, A. A.

    1985-01-01

    Registration and identification of muons and muon groups penetrating into the ocean depth, can be performed using a modular multilayer detector with high resolution bidimensional readout - deep underwater calorimeter (project NADIR). Laboratory testing of a prototype sensor cell with liquid scintillator in light-tight casing, testifies to the practicability of the full-scale experiment within reasonable expences.

  9. Proceedings of the International Workshop on Low Energy Muon Science: LEMS`93

    SciTech Connect

    Leon, M.

    1994-01-01

    This report contains papers on research with low energy muons. Topics cover fundamental electroweak physics; muonic atoms and molecules, and muon catalyzed fusion; muon spin research; and muon facilities. These papers have been indexed and cataloged separately.

  10. R&D Toward a Neutrino Factory and Muon Collider

    SciTech Connect

    Zisman, Michael S

    2011-03-20

    Significant progress has been made in recent years in R&D towards a neutrino factory and muon collider. The U.S. Muon Accelerator Program (MAP) has been formed recently to expedite the R&D efforts. This paper will review the U.S. MAP R&D programs for a neutrino factory and muon collider. Muon ionization cooling research is the key element of the program. The first muon ionization cooling demonstration experiment, MICE (Muon Ionization Cooling Experiment), is under construction now at RAL (Rutherford Appleton Laboratory) in the UK. The current status of MICE will be described.

  11. Muon-fluorine entangled states in molecular magnets.

    PubMed

    Lancaster, T; Blundell, S J; Baker, P J; Brooks, M L; Hayes, W; Pratt, F L; Manson, J L; Conner, M M; Schlueter, J A

    2007-12-31

    The information accessible from a muon-spin relaxation experiment can be limited due to a lack of knowledge of the precise muon stopping site. We demonstrate here the possibility of localizing a spin polarized muon in a known stopping state in a molecular material containing fluorine. The muon-spin precession that results from the entangled nature of the muon spin and surrounding nuclear spins is sensitive to the nature of the stopping site. We use this property to identify three classes of sites that occur in molecular magnets and describe the extent to which the muon distorts its surroundings.

  12. Development of low noise cosmic ray muon detector for imaging density structure of Usu Volcano, Hokkaido, Japan

    NASA Astrophysics Data System (ADS)

    Kusagaya, T.; Tanaka, H.; Taketa, A.; Oshima, H.; Maekawa, T.

    2012-12-01

    We are developing low noise cosmic ray muon detector to image a density structure of Usu Volcano, Hokkaido, Japan by muon radiography. Intensity of cosmic ray muon penetrating through the object is expressed as a function of the product of muon path length and density along muon path. And, the intensity of penetrating muon steeply decreases if muon path length becomes longer or density along muon path becomes larger. The detector that we are developing is called hodoscope that consists of multiple Position Sensitive Detectors (PSDs). A PSD has NxM grids consisting of N vertically aligned Scintillation Counters (SC: a plastic scintillator attached to a photo multiplier tube) and M horizontally aligned SCs. We can identify a muon path direction with two or more PSDs by connecting muon-detecting points in each PSD. But, Usu Volcano is so large that the intensity of penetrating muon becomes lower, and then noise rate becomes higher: the count of penetrating cosmic ray muon is estimated to be a few counts per month with the detector of which has the cross-section area of one square meter and the solid angle of 0.01 steradian. The noise is defined as a particle other than the muon penetrating the observed object such as electrons, photons, vertically arriving muons and so on. If noise rate becomes higher, the measured intensity of penetrating muon becomes higher than the theoretical intensity of that. Then we get a wrong result as if there were matter of lower density relative to real. So we need to develop a low noise detector. The ElectroMagnetic (EM) shower that consists of many electrons and photons is thought to be one of noise. When EM shower reaches the detector, each PSD detects arriving particles and detecting points are sometimes connected by a straight line. In that case, we cannot discriminate the penetrating muon from EM shower, and we count it as a muon event. This results noise. In order to discriminate the noise event, the use of more PSDs for our

  13. Study of muon-induced neutron production using accelerator muon beam at CERN

    SciTech Connect

    Nakajima, Y.; Lin, C. J.; Ochoa-Ricoux, J. P.; Draeger, E.; White, C. G.; Luk, K. B.; Steiner, H.

    2015-08-17

    Cosmogenic muon-induced neutrons are one of the most problematic backgrounds for various underground experiments for rare event searches. In order to accurately understand such backgrounds, experimental data with high-statistics and well-controlled systematics is essential. We performed a test experiment to measure muon-induced neutron production yield and energy spectrum using a high-energy accelerator muon beam at CERN. We successfully observed neutrons from 160 GeV/c muon interaction on lead, and measured kinetic energy distributions for various production angles. Works towards evaluation of absolute neutron production yield is underway. This work also demonstrates that the setup is feasible for a future large-scale experiment for more comprehensive study of muon-induced neutron production.

  14. Negative muon chemistry: the quantum muon effect and the finite nuclear mass effect.

    PubMed

    Posada, Edwin; Moncada, Félix; Reyes, Andrés

    2014-10-09

    The any-particle molecular orbital method at the full configuration interaction level has been employed to study atoms in which one electron has been replaced by a negative muon. In this approach electrons and muons are described as quantum waves. A scheme has been proposed to discriminate nuclear mass and quantum muon effects on chemical properties of muonic and regular atoms. This study reveals that the differences in the ionization potentials of isoelectronic muonic atoms and regular atoms are of the order of millielectronvolts. For the valence ionizations of muonic helium and muonic lithium the nuclear mass effects are more important. On the other hand, for 1s ionizations of muonic atoms heavier than beryllium, the quantum muon effects are more important. In addition, this study presents an assessment of the nuclear mass and quantum muon effects on the barrier of Heμ + H2 reaction.

  15. The new high field photoexcitation muon spectrometer at the ISIS pulsed neutron and muon source.

    PubMed

    Yokoyama, K; Lord, J S; Murahari, P; Wang, K; Dunstan, D J; Waller, S P; McPhail, D J; Hillier, A D; Henson, J; Harper, M R; Heathcote, P; Drew, A J

    2016-12-01

    A high power pulsed laser system has been installed on the high magnetic field muon spectrometer (HiFi) at the International Science Information Service pulsed neutron and muon source, situated at the STFC Rutherford Appleton Laboratory in the UK. The upgrade enables one to perform light-pump muon-probe experiments under a high magnetic field, which opens new applications of muon spin spectroscopy. In this report we give an overview of the principle of the HiFi laser system and describe the newly developed techniques and devices that enable precisely controlled photoexcitation of samples in the muon instrument. A demonstration experiment illustrates the potential of this unique combination of the photoexcited system and avoided level crossing technique.

  16. Atmospheric Muon Lifetime, Standard Model of Particles and the Lead Stopping Power for Muons

    NASA Astrophysics Data System (ADS)

    Gutarra-Leon, Angel; Barazandeh, Cioli; Majewski, Walerian

    2017-01-01

    The muon is a fundamental particles of matter. It decays into three other leptons through an exchange of the weak vector bosons W +/W-. Muons are present in the atmosphere from cosmic ray showers. By detecting the time delay between arrival of the muon and an appearance of the decay electron in our detector, we'll measure muon's lifetime at rest. From the lifetime we should be able to find the ratio gw /MW of the weak coupling constant gw (a weak analog of the electric charge) to the mass of the W-boson MW. Vacuum expectation value v of the Higg's field, which determines the masses of all particles of the Standard Model (SM), could be then calculated from our muon experiment as v =2MWc2/gw =(τ m μc2/6 π3ĥ)1/4m μc2 in terms of muon mass mµand muon lifetime τ only. Using known experimental value for MWc2 = 80.4 GeV we'll find the weak coupling constant gw. Using the SM relation e =gwsin θ√ hc ɛ0 with the experimental value of the Z0-photon weak mixing angle θ = 29o we could find from our muon lifetime the value of the elementary electric charge e. We'll determine the sea-level fluxes of low-energy and high-energy cosmic muons, then we'll shield the detector with varying thicknesses of lead plates and find the energy-dependent muon stopping power in lead.

  17. Sudden stratospheric warmings seen in MINOS deep underground muon data

    SciTech Connect

    Osprey, S.; Barnett, J.; Smith, J.; Adamson, P.; Andreopoulos, C.; Arms, K.E.; Armstrong, R.; Auty, D.J.; Ayres, D.S.; Baller, B.; Barnes, P.D., Jr.; /LLNL, Livermore /Oxford U.

    2009-01-01

    The rate of high energy cosmic ray muons as measured underground is shown to be strongly correlated with upper-air temperatures during short-term atmospheric (10-day) events. The effects are seen by correlating data from the MINOS underground detector and temperatures from the European Centre for Medium Range Weather Forecasts during the winter periods from 2003-2007. This effect provides an independent technique for the measurement of meteorological conditions and presents a unique opportunity to measure both short and long-term changes in this important part of the atmosphere.

  18. D0 Silicon Upgrade: Scaffolding Plateform at Muon Chamber

    SciTech Connect

    Kuwazaki, Andrew; /Fermilab

    1995-07-28

    The design for the scaffolding platform which will be connected to the muon chamber wall was analyzed for a load rating of 400 lbs. The platform is supported on each end and the calculations were done for the full 400 lbs. on the end of the horizontal beam. Both members were analyzed for maximum stresses and were compared to the allowable stress, and both members were found to be acceptable in accordance with the ASCE and AISC specifications. The only recommendation is for all the 3/8-inch steel bolt to be of grade 5 or better. This is necessary to insure safety.

  19. Radiative capture reactions in astrophysics

    DOE PAGES

    Brune, Carl R.; Davids, Barry

    2015-08-07

    Here, the radiative capture reactions of greatest importance in nuclear astrophysics are identified and placed in their stellar contexts. Recent experimental efforts to estimate their thermally averaged rates are surveyed.

  20. Neutrino mass implications for muon decay parameters

    SciTech Connect

    Erwin, Rebecca J.; Kile, Jennifer; Ramsey-Musolf, Michael J.; Wang Peng

    2007-02-01

    We use the scale of neutrino mass and naturalness considerations to obtain model-independent expectations for the magnitude of possible contributions to muon decay Michel parameters from new physics above the electroweak symmetry-breaking scale. Focusing on Dirac neutrinos, we obtain a complete basis of dimension four and dimension six effective operators that are invariant under the gauge symmetry of the standard model and that contribute to both muon decay and neutrino mass. We show that - in the absence of fine tuning - the most stringent neutrino-mass naturalness bounds on chirality-changing vector operators relevant to muon decay arise from one-loop operator mixing. The bounds we obtain on their contributions to the Michel parameters are 2 orders of magnitude stronger than bounds previously obtained in the literature. In addition, we analyze the implications of one-loop matching considerations and find that the expectations for the size of various scalar and tensor contributions to the Michel parameters are considerably smaller than derived from previous estimates of two-loop operator mixing. We also show, however, that there exist gauge-invariant operators that generate scalar and tensor contributions to muon decay but whose flavor structure allows them to evade neutrino-mass naturalness bounds. We discuss the implications of our analysis for the interpretation of muon-decay experiments.

  1. In-situ Calibration of Detectors using Muon-induced Neutrons

    SciTech Connect

    Marleau, Peter; Reyna, David

    2016-10-31

    In this work we investigate a method that confirms the operability of neutron detectors requiring neither radiological sources nor radiation generating devices. This is desirable when radiological sources are not available, but confidence in the functionality of the instrument is required. The “source”, based on the production of neutrons in high-Z materials by muons, provides a tagged, low-background and consistent rate of neutrons that can be used to check the functionality of or calibrate a detector. Using a Monte Carlo guided optimization, an experimental apparatus was designed and built to evaluate the feasibility of this technique. Through a series of trial measurements in a variety of locations we show that gated muon-induced neutrons appear to provide a consistent source of neutrons (35.9 ± 2.3 measured neutrons/10,000 muons in the instrument) under normal environmental variability (less than one statistical standard deviation for 10,000 muons) with a combined environmental + statistical uncertainty of ~18% for 10,000 muons. This is achieved in a single 21-22 minute measurement at sea level.

  2. Pion production for neutrino factories and muon colliders

    SciTech Connect

    Mokhov, N.V.; Guidman, K.K.; Strait, J.B.; Striganov, S.I.; /Fermilab

    2009-12-01

    Optimization of pion and muon production/collection for neutrino factories and muon colliders is described along with recent developments of the MARS15 code event generators and effects influencing the choice of the optimal beam energy.

  3. Design note of an air-cooled 2 ft x 2 ft x 10. 5 ft long muon spoiler

    SciTech Connect

    Visser, A.; Pathiyil, J.

    1988-01-06

    This note describes the construction of a muon spoiler (magnetized steel assembly) with a cross section of 2 ft by 2 ft and a length of 10.5 ft. Two such spoilers are operated in series at an average field of about 15 kGauss, from one 100 ADC, 40 V power supply. The purpose of the spoilers is to prevent muons from easily escaping beyond the muon laboratory experimental area by bending them down so that they have to pass through more earth. The spoilers reduce the muon dose rate beyond the experimental area by about a factor of 15 to 20. These types of spoilers are not precision devices. They were inexpensive to build from scrap materials using rough flame cutting methods. It took about 14 days to fabricate them.

  4. Negative muon spin precession measurement of the hyperfine states of muonic sodium

    NASA Astrophysics Data System (ADS)

    Brewer, J. H.; Ghandi, K.; Froese, A. M.; Fryer, B. A.

    2005-05-01

    Both hyperfine states of muonic 23Na and the rate R of conversion between them have been observed directly in a high field negative muon spin precession experiment using a backward muon beam with transverse spin polarization. The result in metallic sodium, R=13.7±2.2μs-1, is consistent with Winston's prediction in 1963 based on Auger emission of core electrons, and with the measurements of Gorringe et al. in Na metal, but not with their smaller result in NaF. In NaOH we find R=23.5±8μs-1, leaving medium-dependent effects ambiguous.

  5. Studies of muon-induced radioactivity at NuMI

    SciTech Connect

    Boehnlein, David j.; Leveling, A.F.; Mokhov, N.V.; Vaziri, K.; Iwamoto, Y.; Kasugai, Y.; Matsuda, N.; Nakashima, H.; Sakamoto, Y.; Hagiwara, M.; Iwase, Hiroshi; /KEK, Tsukuba /Kyoto U., KURRI /Pohang Accelerator Lab. /Shimizu, Tokyo /Tohoku U.

    2009-12-01

    The JASMIN Collaboration has studied the production of radionuclides by muons in the muon alcoves of the NuMI beamline at Fermilab. Samples of aluminum and copper are exposed to the muon field and counted on HpGe detectors when removed to determine their content of radioactive isotopes. We compare the results to MARS simulations and discuss the radiological implications for neutrino factories and muon colliders.

  6. Physics Studies for the CMS muon system upgrade with triple-GEM detectors

    NASA Astrophysics Data System (ADS)

    Caputo, C.

    2014-12-01

    The CMS collaboration considers upgrading the muon forward region with Gas Electron Multiplier (GEM) chambers, which are able to handle the extreme particle rates expected in this region along with a high spatial resolution. This allows to combine tracking and triggering capabilities, resulting in a lower trigger threshold along with improved muon identification and track reconstruction. In the last year the GEM project took a major leap forward by integrating triple-GEM chambers in the official CMS software, allowing physics studies to be carried out. Several benchmark analyses have been studied for the impact of such detector upgrade on the physics performance. In this contribution the status of the CMS upgrade project with the usage of GEM detector will be reviewed, discussing the trigger, the muon reconstruction performance, and the impact on the physics analyses.

  7. Overview of large area triple-GEM detectors for the CMS forward muon upgrade

    NASA Astrophysics Data System (ADS)

    Abbaneo, D.; Abbas, M.; Abbrescia, M.; Abi Akl, M.; Aboamer, O.; Acosta, D.; Ahmad, A.; Ahmed, W.; Aleksandrov, A.; Altieri, P.; Asawatangtrakuldee, C.; Aspell, P.; Assran, Y.; Awan, I.; Bally, S.; Ban, Y.; Banerjee, S.; Barashko, V.; Barria, P.; Bencze, G.; Beni, N.; Benussi, L.; Bhopatkar, V.; Bianco, S.; Bos, J.; Bouhali, O.; Braghieri, A.; Braibant, S.; Buontempo, S.; Calabria, C.; Caponero, M.; Caputo, C.; Cassese, F.; Castaneda, A.; Cauwenbergh, S.; Cavallo, F. R.; Celik, A.; Choi, M.; Choi, S.; Christiansen, J.; Cimmino, A.; Colafranceschi, S.; Colaleo, A.; Garcia, A. Conde; Czellar, S.; Dabrowski, M. M.; De Lentdecker, G.; De Oliveira, R.; de Robertis, G.; Dildick, S.; Dorney, B.; Endroczi, G.; Errico, F.; Fenyvesi, A.; Ferry, S.; Furic, I.; Giacomelli, P.; Gilmore, J.; Golovtsov, V.; Guiducci, L.; Guilloux, F.; Gutierrez, A.; Hadjiiska, R. M.; Hauser, J.; Hoepfner, K.; Hohlmann, M.; Hoorani, H.; Iaydjiev, P.; Jeng, Y. G.; Kamon, T.; Karchin, P.; Korytov, A.; Krutelyov, S.; Kumar, A.; Kim, H.; Lee, J.; Lenzi, T.; Litov, L.; Loddo, F.; Madorsky, A.; Maerschalk, T.; Maggi, M.; Magnani, A.; Mal, P. K.; Mandal, K.; Marchioro, A.; Marinov, A.; Majumdar, N.; Merlin, J. A.; Mitselmakher, G.; Mohanty, A. K.; Mohapatra, A.; Molnar, J.; Muhammad, S.; Mukhopadhyay, S.; Naimuddin, M.; Nuzzo, S.; Oliveri, E.; Pant, L. M.; Paolucci, P.; Park, I.; Passeggio, G.; Pavlov, B.; Philipps, B.; Piccolo, D.; Postema, H.; Puig Baranac, A.; Radi, A.; Radogna, R.; Raffone, G.; Ranieri, A.; Rashevski, G.; Riccardi, C.; Rodozov, M.; Rodrigues, A.; Ropelewski, L.; RoyChowdhury, S.; Ryu, G.; Ryu, M. S.; Safonov, A.; Salva, S.; Saviano, G.; Sharma, A.; Sharma, A.; Sharma, R.; Shah, A. H.; Shopova, M.; Sturdy, J.; Sultanov, G.; Swain, S. K.; Szillasi, Z.; Talvitie, J.; Tatarinov, A.; Tuuva, T.; Tytgat, M.; Vai, I.; Stenis, M. Van; Venditti, R.; Verhagen, E.; Verwilligen, P.; Vitulo, P.; Volkov, S.; Vorobyev, A.; Wang, D.; Wang, M.; Yang, U.; Yang, Y.; Yonamine, R.; Zaganidis, N.; Zenoni, F.; Zhang, A.

    2017-02-01

    In order to cope with the harsh environment expected from the high luminosity LHC, the CMS forward muon system requires an upgrade. The two main challenges expected in this environment are an increase in the trigger rate and increased background radiation leading to a potential degradation of the particle ID performance. Additionally, upgrades to other subdetectors of CMS allow for extended coverage for particle tracking, and adding muon system coverage to this region will further enhance the performance of CMS. Following an extensive R&D program, CMS has identified triple-foil gas electron multiplier (GEM) detectors as a solution for the first muon station in the region 1.6 < | η | < 2.2, while continuing R&D is ongoing for additional regions.

  8. Searching for Dark Matter using the NOvA upward-going muon trigger

    NASA Astrophysics Data System (ADS)

    Principato, Cristiana; Group, Robert; Norman, Andrew; Aliaga, Leonidas; Ding, Pengfei; Tsaris, Aristeidis; Oksuzian, Yuri; NOvA Collaboration

    2017-01-01

    The NOvA collaboration has constructed a 14,000 ton, fine-grained, low-Z, total absorption tracking calorimeter at an off-axis angle to an upgraded NuMI neutrino beam. This detector, with its excellent granularity and energy resolution and relatively low-energy neutrino thresholds, was designed to observe electron neutrino appearance in a muon neutrino beam, but it also has unique capabilities suitable for more exotic efforts. In fact, if sufficient cosmic ray background rejection can be demonstrated, NO νA will be capable of a competitive indirect dark matter search for low-mass Weakly-Interacting Massive Particles (WIMPs). The cosmic ray muon rate at the NO νA far detector is approximately 100 kHz and provides the primary challenge for triggering and optimizing such a search analysis. We present the first dark matter search results using the full dataset collected with the upward-going muon trigger.

  9. Capturing Callisto

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The New Horizons Long Range Reconnaissance Imager (LORRI) captured these two images of Jupiter's outermost large moon, Callisto, as the spacecraft flew past Jupiter in late February. New Horizons' closest approach distance to Jupiter was 2.3 million kilometers (1.4 million miles), not far outside Callisto's orbit, which has a radius of 1.9 million kilometers (1.2 million miles). However, Callisto happened to be on the opposite side of Jupiter during the spacecraft's pass through the Jupiter system, so these images, taken from 4.7 million kilometers (3.0 million miles) and 4.2 million kilometers (2.6 million miles) away, are the closest of Callisto that New Horizons obtained.

    Callisto's ancient, crater-scarred surface makes it very different from its three more active sibling satellites, Io, Europa and Ganymede. Callisto, 4,800 kilometers (3000 miles) in diameter, displays no large-scale geological features other than impact craters, and every bright spot in these images is a crater. The largest impact feature on Callisto, the huge basin Valhalla, is visible as a bright patch at the 10 o'clock position. The craters are bright because they have excavated material relatively rich in water ice from beneath the dark, dusty material that coats most of the surface.

    The two images show essentially the same side of Callisto -- the side that faces Jupiter -- under different illumination conditions. The images accompanied scans of Callisto's infrared spectrum with New Horizons' Linear Etalon Imaging Spectral Array (LEISA). The New Horizons science team designed these scans to study how the infrared spectrum of Callisto's water ice changes as lighting and viewing conditions change, and as the ice cools through Callisto's late afternoon. The infrared spectrum of water ice depends slightly on its temperature, and a goal of New Horizons when it reaches the Pluto system (in 2015) is to use the water ice features in the spectrum of Pluto's moon Charon, and

  10. Muon Tracking to Detect Special Nuclear Materials

    SciTech Connect

    Schwellenbach, D.; Dreesen, W.; Green, J. A.; Tibbitts, A.; Schotik, G.; Borozdin, K.; Bacon, J.; Midera, H.; Milner, C.; Morris, C.; Perry, J.; Barrett, S.; Perry, K.; Scott, A.; Wright, C.; Aberle, D.

    2013-03-18

    Previous experiments have proven that nuclear assemblies can be imaged and identified inside of shipping containers using vertical trajectory cosmic-ray muons with two-sided imaging. These experiments have further demonstrated that nuclear assemblies can be identified by detecting fission products in coincidence with tracked muons. By developing these technologies, advanced sensors can be designed for a variety of warhead monitoring and detection applications. The focus of this project is to develop tomographic-mode imaging using near-horizontal trajectory muons in conjunction with secondary particle detectors. This will allow imaging in-situ without the need to relocate the objects and will enable differentiation of special nuclear material (SNM) from other high-Z materials.

  11. Muon (g-2) Technical Design Report

    SciTech Connect

    Grange, J.

    2015-01-27

    The Muon (g-2) Experiment, E989 at Fermilab, will measure the muon anomalous magnetic moment a factor-of-four more precisely than was done in E821 at the Brookhaven National Laboratory AGS. The E821 result appears to be greater than the Standard-Model prediction by more than three standard deviations. When combined with expected improvement in the Standard-Model hadronic contributions, E989 should be able to determine definitively whether or not the E821 result is evidence for physics beyond the Standard Model. After a review of the physics motivation and the basic technique, which will use the muon storage ring built at BNL and now relocated to Fermilab, the design of the new experiment is presented. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-2/3 approval.

  12. Muon trackers for imaging a nuclear reactor

    NASA Astrophysics Data System (ADS)

    Kume, N.; Miyadera, H.; Morris, C. L.; Bacon, J.; Borozdin, K. N.; Durham, J. M.; Fuzita, K.; Guardincerri, E.; Izumi, M.; Nakayama, K.; Saltus, M.; Sugita, T.; Takakura, K.; Yoshioka, K.

    2016-09-01

    A detector system for assessing damage to the cores of the Fukushima Daiichi nuclear reactors by using cosmic-ray muon tomography was developed. The system consists of a pair of drift-tube tracking detectors of 7.2× 7.2-m2 area. Each muon tracker consists of 6 x-layer and 6 y-layer drift-tube detectors. Each tracker is capable of measuring muon tracks with 12 mrad angular resolutions, and is capable of operating under 50-μ Sv/h radiation environment by removing gamma induced background with a novel time-coincidence logic. An estimated resolution to observe nuclear fuel debris at Fukushima Daiichi is 0.3 m when the core is imaged from outside the reactor building.

  13. Annual recapture and survival rates of two non-breeding adult populations of Roseate Terns Stema dougallii captured on the Great Barrier Reef, Australia, and estimates of their population sizes

    USGS Publications Warehouse

    O'Neill, P.; Minton, C.D.T.; Nisbet, I.C.T.; Hines, J.E.

    2008-01-01

    Capture-recapture data from two disparate breeding populations of Roseate Terns (Sterna dougallii) captured together as non-breeding individuals from 2002 to 2007 in the southern Great Barrier Reef. Australia were analyzed for both survival rate and recapture rate. The average annual survival rate for the birds from the Asian population (S. d. bangsi) (0.901) is higher than that of the other population of unknown breeding origin (0.819). There was large variability in survival in both populations among years, but the average survival rate of 0.85 is similar to estimates for the same species in North America. The Cormack-Jolly-Seber models used in program MARK to estimate survival rates also produced estimated of recapture probabilities and population sizes. These estimates of population size were 29,000 for S. D. bangsi and 8,300 for the study area and much larger than the documented numbers in the likely breeding areas, suggesting that many breeding sites are currently unknown.

  14. Higgs boson and Z physics at the first muon collider

    SciTech Connect

    Demarteau, M.; Han, T.

    1998-01-01

    The potential for the Higgs boson and Z-pole physics at the first muon collider is summarized, based on the discussions at the ``Workshop on the Physics at the First Muon Collider and at the Front End of a Muon Collider``.

  15. Characterisation of the muon beams for the Muon Ionisation Cooling Experiment

    SciTech Connect

    Adams, D.; et al.,

    2013-10-01

    A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.5--2.3 \\pi mm-rad horizontally and 0.6--1.0 \\pi mm-rad vertically, a horizontal dispersion of 90--190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE.

  16. Intensity of Upward Muon Flux Due to Cosmic-Ray Neutrinos Produced in the Atmosphere

    DOE R&D Accomplishments Database

    Lee, T. D.; Robinson, H.; Schwartz, M.; Cool, R.

    1963-06-01

    Calculations were performed to determine the upward going muon flux leaving the earth's surface after production by cosmic-ray neutrinos in the crust. Only neutrinos produced in the earth's atmosphere are considered. Rates of the order of one per 100 sq m/day might be expected if an intermediate boson exists and has a mass less than 2 Bev. (auth)

  17. Thunderstorms' atmospheric electric field effects in the intensity of cosmic ray muons and in neutron monitor data

    NASA Astrophysics Data System (ADS)

    Dorman, L. I.; Dorman, I. V.; Iucci, N.; Parisi, M.; Ne'Eman, Y.; Pustil'Nik, L. A.; Signoretti, F.; Sternlieb, A.; Villoresi, G.; Zukerman, I. G.

    2003-05-01

    Theoretical and experimental results on the influence of thunderstorms' atmospheric electric field on cosmic ray secondary components are presented. On the basis of the approach proposed by [1987], theoretical models for a correct numerical evaluation of these effects on hard muon, soft muon, and neutron monitor component are developed. For hard and soft muons the validity of the models are checked by their comparison with experimental results of the Baksan muon detector. For the first time, the effect of thunderstorms' atmospheric electric field on cosmic rays is investigated by simultaneous measurements of one-minute neutron monitor intensity and of atmospheric electric field at the Emilio Segre' Observatory on Mt. Hermon (Israel). A series of large thunderstorms during February 2000 is investigated; for each thunderstorm the maximum atmospheric electric field intensity was ranging from 10 to about 100 kV/m. Clear correlation between field intensity and neutron monitor intensity variations is presented for total intensity and for different detected multiplicity channels. This correlation is quantitatively in agreement with the developed model which takes into account the formation of short-living meso-atoms by the capture of slow negative muons in the lead of the monitor. The effect is relevant only for neutron events with detected multiplicity m = 1 and evident for multiplicity m = 2; the other multiplicity channels are not influenced by neutrons from meso-atoms.

  18. An additional study of multi-muon events produced in $p\\bar{p}$ collisions at $\\sqrt{s}=1.96$ TeV

    SciTech Connect

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Apresyan, A.; Arisawa, T.; Artikov, A.; /Dubna, JINR /Fermilab

    2011-11-01

    We present one additional study of multi-muon events produced at the Fermilab Tevatron collider and recorded by the CDF II detector. We use a data set acquired with a dedicated dimuon trigger and corresponding to an integrated luminosity of 3.9 fb{sup -1}. We investigate the distribution of the azimuthal angle between the two trigger muons in events containing at least four additional muon candidates to test the compatibility of these events with originating from known QCD processes. We find that this distribution is markedly different from what is expected from such QCD processes and this observation strongly disfavours the possibility that multi-muon events result from an underestimate of the rate of misidentified muons in ordinary QCD events.

  19. Muon neutrino CCQE at MINERvA

    SciTech Connect

    Betancourt, M.

    2016-12-13

    A precise understanding of quasi-elastic interactions is crucial to measure neutrino oscillations. The MINERvA experiment is currently working on different analyses of muon neutrino charged current quasi-elastic interactions. Here, we present updates to the previous quasi-elastic measurement, using a new flux, and we present the status of several analyses in progress; including double differential cross sections, a study of final state interactions using a sample with muon and a proton and the status of the CCQE analysis in the medium energy neutrino beam.

  20. Muon production in extended air shower simulations.

    PubMed

    Pierog, T; Werner, K

    2008-10-24

    Whereas air shower simulations are very valuable tools for interpreting cosmic ray data, there is a long-standing problem: it is difficult to accommodate at the same time the longitudinal development of air showers and the number of muons measured on the ground. Using a new hadronic interaction model (EPOS) in air shower simulations produces much more muons, in agreement with results from the HiRes-MIA experiment. We find that this is mainly due to a better description of (anti) baryon production in hadronic interactions. This is an aspect of air shower physics which has been neglected so far.

  1. Muon Neutrino Disappearance Measurement at MINOS+

    NASA Astrophysics Data System (ADS)

    Carroll, Thomas; Minos+ Collaboration

    2017-01-01

    The MINOS experiment ran from 2003 until 2012 and produced some of the best precision measurements of the atmospheric neutrino oscillation parameters Δm322 and θ23 using muon neutrino disappearance of beam and atmospheric neutrinos and electron neutrino appearance of beam neutrinos. The MINOS+ experiment succeeded MINOS in September 2013. For almost three years MINOS+ collected data from the Medium Energy NuMI neutrino beam at Fermilab. Results of the muon neutrino disappearance analysis from the first two years of MINOS+ data will be presented. These results will be compared to and combined with the MINOS measurement.

  2. A COMPLETE SCHEME FOR A MUON COLLIDER.

    SciTech Connect

    PALMER,R.B.; BERG, J.S.; FERNOW, R.C.; GALLARDO, J.C.; KIRK, H.G.; ALEXAHIN, Y.; NEUFFER, D.; KAHN, S.A.; SUMMERS, D.

    2007-09-01

    A complete scheme for production, cooling, acceleration, and ring for a 1.5 TeV center of mass muon collider is presented, together with parameters for two higher energy machines. The schemes starts with the front end of a proposed neutrino factory that yields bunch trains of both muon signs. Six dimensional cooling in long-period helical lattices reduces the longitudinal emittance until it becomes possible to merge the trains into single bunches, one of each sign. Further cooling in all dimensions is applied to the single bunches in further helical lattices. Final transverse cooling to the required parameters is achieved in 50 T solenoids.

  3. Searches for violation of muon number conservation

    SciTech Connect

    Redwine, R.P.

    1981-01-01

    The question of violation of muon number conservation is one which has occupied considerable attention and resources in recent years. The first generation of experiments at the medium energy accelerators has now been completed and the next generation of experiments is ready to begin. The history of muon number conservation is reviewed, including the reasons for the present belief that the conservation law may not be exact. The experiments that have been completed in the last few years are discussed. The new experiments that are being mounted and planned at several laboratories are discussed, and the relationship of these types of experiments to other studies, such as searches for neutrino oscillations, are considered.

  4. Muon Neutrino CCQE at MINERvA

    NASA Astrophysics Data System (ADS)

    Betancourt, M.

    A precise understanding of quasi-elastic interactions is crucial to measure neutrino oscillations. The MINERvA experiment is currently working on different analyses of muon neutrino charged current quasi-elastic interactions. We present updates to the previous quasi-elastic measurement, using a new flux, and we present the status of several analyses in progress; including double differential cross sections, a study of final state interactions using a sample with muon and a proton and the status of the CCQE analysis in the medium energy neutrino beam.

  5. Flavor tagging with muons at SLAC

    NASA Astrophysics Data System (ADS)

    Prepost, R.

    1984-05-01

    Identification of muons in hadronic events from e+e- annihilation observed in the MAC detector at PEP at √s=29 GeV provides flavor tagging of heavy quark mesons. A sample enriched in events from bb production is obtained and the b quark fragmentation function is determined. The b quark is found to fragment predominantly with high values of z, with =0.8+/-0.1 and to have an overall semileptonic branching ratio to muons of (15.5+5.4-2.9)%. The sample also provides flavor tagged hadronic jets. Invariant mass and charged multiplicity distributions are presented.

  6. Development of a carbonate absorption-based process for post-combustion CO2 capture: The role of biocatalyst to promote CO2 absorption rate

    USGS Publications Warehouse

    Lu, Y.; Ye, X.; Zhang, Z.; Khodayari, A.; Djukadi, T.

    2011-01-01

    An Integrated Vacuum Carbonate Absorption Process (IVCAP) for post-combustion carbon dioxide (CO2) capture is described. IVCAP employs potassium carbonate (PC) as a solvent, uses waste or low quality steam from the power plant for CO2 stripping, and employs a biocatalyst, carbonic anhydrase (CA) enzyme, for promoting the CO2 absorption into PC solution. A series of experiments were performed to evaluate the activity of CA enzyme mixed in PC solutions in a stirred tank reactor system under various temperatures, CA dosages, CO2 loadings, CO2 partial pressures, and the presence of major flue gas contaminants. It was demonstrated that CA enzyme is an effective biocatalyst for CO2 absorption under IVCAP conditions. ?? 2011 Published by Elsevier Ltd.

  7. Low-energy muon [LEM] study of Zn-phthalocyanine and ZnO thin films

    NASA Astrophysics Data System (ADS)

    Alberto, H. V.; Piroto Duarte, J.; Weidinger, A.; Vilão, R. C.; Gil, J. M.; Ayres de Campos, N.; Fostiropoulos, K.; Prokscha, T.; Suter, A.; Morenzoni, E.

    2009-04-01

    Implantation of low-energy muons in zinc-phthalocyanine (ZnPc) thin-films leads to the formation of muoniated radical states, the fast decaying of the μSR signal at low fields being a clear indication of muonium formation. The formation probability of these paramagnetic states is independent of the implantation depth and amounts, as in the bulk, to approximately 100% of all muons. In these molecular crystals the formation of muonium is a highly local effect and is fairly independent of crystalline structure and defects in the sample. In contrast to that, in vapour-grown ZnO films the paramagnetic signal known from bulk experiments is not observed, even for the deeper implantations. We suggest that in this case muonium is not formed due to the low concentration of free electrons. In these strongly distorted films, electrons are captured at defects and are not available for muonium formation.

  8. PREFACE: Muon spin rotation, relaxation or resonance

    NASA Astrophysics Data System (ADS)

    Heffner, Robert H.; Nagamine, Kanetada

    2004-10-01

    To a particle physicist a muon is a member of the lepton family, a heavy electron possessing a mass of about 1/9 that of a proton and a spin of 1/2, which interacts with surrounding atoms and molecules electromagnetically. Since its discovery in 1937, the muon has been put to many uses, from tests of special relativity to deep inelastic scattering, from studies of nuclei to tests of weak interactions and quantum electrodynamics, and most recently, as a radiographic tool to see inside heavy objects and volcanoes. In 1957 Richard Garwin and collaborators, while conducting experiments at the Columbia University cyclotron to search for parity violation, discovered that spin-polarized muons injected into materials might be useful to probe internal magnetic fields. This eventually gave birth to the modern field of muSR, which stands for muon spin rotation, relaxation or resonance, and is the subject of this special issue of Journal of Physics: Condensed Matter. Muons are produced in accelerators when high energy protons (generally >500 MeV) strike a target like graphite, producing pions which subsequently decay into muons. Most experiments carried out today use relatively low-energy (~4 MeV), positively-charged muons coming from pions decaying at rest in the skin of the production target. These muons have 100% spin polarization, a range in typical materials of about 180 mg cm-2, and are ideal for experiments in condensed matter physics and chemistry. Negatively-charged muons are also occasionally used to study such things as muonic atoms and muon-catalysed fusion. The muSR technique provides a local probe of internal magnetic fields and is highly complementary to inelastic neutron scattering and nuclear magnetic resonance, for example. There are four primary muSR facilities in the world today: ISIS (Didcot, UK), KEK (Tsukuba, Japan), PSI (Villigen, Switzerland) and TRIUMF (Vancouver, Canada), serving about 500 researchers world-wide. A new facility, JPARC (Tokai, Japan

  9. nuSTORM - Neutrinos from STORed Muons: Letter of Intent to the Fermilab Physics Advisory Committee

    SciTech Connect

    Kyberd, P.; Smith, D.R.; Coney, L.; Pascoli, S.; Ankenbrandt, C.; Brice, S.J.; Bross, A.D.; Cease, H.; Kopp, J.; Mokhov, N.; Morfin, J.; /Fermilab /Yerkes Observ. /Glasgow U. /Imperial Coll., London /Valencia U. /Jefferson Lab /Kyoto U. /Northwestern U. /Osaka U.

    2012-06-01

    The idea of using a muon storage ring to produce a high-energy ({approx_equal} 50 GeV) neutrino beam for experiments was first discussed by Koshkarev in 1974. A detailed description of a muon storage ring for neutrino oscillation experiments was first produced by Neuffer in 1980. In his paper, Neuffer studied muon decay rings with E{sub {mu}} of 8, 4.5 and 1.5 GeV. With his 4.5 GeV ring design, he achieved a figure of merit of {approx_equal} 6 x 10{sup 9} useful neutrinos per 3 x 10{sup 13} protons on target. The facility we describe here ({nu}STORM) is essentially the same facility proposed in 1980 and would utilize a 3-4 GeV/c muon storage ring to study eV-scale oscillation physics and, in addition, could add significantly to our understanding of {nu}{sub e} and {nu}{sub {mu}} cross sections. In particular the facility can: (1) address the large {Delta}m{sup 2} oscillation regime and make a major contribution to the study of sterile neutrinos, (2) make precision {nu}{sub e} and {bar {nu}}{sub e} cross-section measurements, (3) provide a technology ({mu} decay ring) test demonstration and {mu} beam diagnostics test bed, and (4) provide a precisely understood {nu} beam for detector studies. The facility is the simplest implementation of the Neutrino Factory concept. In our case, 60 GeV/c protons are used to produce pions off a conventional solid target. The pions are collected with a focusing device (horn or lithium lens) and are then transported to, and injected into, a storage ring. The pions that decay in the first straight of the ring can yield a muon that is captured in the ring. The circulating muons then subsequently decay into electrons and neutrinos. We are starting with a storage ring design that is optimized for 3.8 GeV/c muon momentum. This momentum was selected to maximize the physics reach for both oscillation and the cross section physics. See Fig. 1 for a schematic of the facility.

  10. Muon-spin-rotation study of the superconducting properties of Mo3Sb7

    NASA Astrophysics Data System (ADS)

    Tran, V. H.; Hillier, A. D.; Adroja, D. T.; Bukowski, Z.

    2008-11-01

    We present the microscopic properties of superconducting state in Mo3Sb7 (Tc=2.2K) using muon-spin rotation measurements. The zero-field-cooled and field-cooled (FC) data with an applied transverse field of 40 mT reveal an irreversibility in the muon relaxation rates and precessional frequencies below 2 K. We have also found an anomaly around 0.5 K, which may be related to a process of the vortex melting or some change in vortex-lattice symmetry. The temperature dependence of FC muon relaxation rate can be analyzed using a phenomenological double-gap s -wave model. The observation of a nonlinear field dependence of the muon relaxation rate is consistent with the occurrence of two superconducting gaps. Moreover, the magnetic penetration depth λ , coherence length ξ , superconducting carrier density ns , and effective-mass enhancement m∗ have been found to be λ≈665nm , ξ≈12.5nm , ns≈1.2×1027carriers/m3 , and m∗≈18.7me , respectively.

  11. River Capture in Disequilibrium Landscapes

    NASA Astrophysics Data System (ADS)

    McCoy, S. W.; Perron, J.; Willett, S.; Goren, L.

    2013-12-01

    The process of river piracy or river capture has long drawn interest as a potential mechanism by which drainage basins large and small evolve towards an equilibrium state. River capture transfers both drainage area and drainage lines from one river basin to another, which can cause large, abrupt shifts in network topology, drainage divide positions, and river incision rates. Despite numerous case studies in which river capture has been proposed to have occurred, there is no general, mechanistic framework for understanding the controls on river capture, nor are there quantitative criteria for determining if capture has occurred. Here we use new metrics of landscape disequilibrium to first identify landscapes in which drainage reorganization is occurring. These metrics are based on a balance between an integral of the contributing drainage area and elevation. In an analysis of rivers in the Eastern United States we find that many rivers are in a state of disequilibrium and are experiencing recent or ongoing area exchange between basins. In these disequilibrium basins we find widespread evidence for network rearrangement via river capture at multiple scales. We then conduct numerical experiments with a 2-D landscape evolution model to explore the conditions in which area exchange among drainage basins is likely to occur as discrete capture events as opposed to continuous divide migration. These experiments indicate that: (1) capture activity increases with the degree of disequilibrium induced by persistent spatial gradients in tectonic forcing or by temporal changes in climate or tectonic forcing; (2) capture activity is strongly controlled by the initial planform drainage network geometry; and (3) capture activity scales with the fluvial incision rate constant in the river power erosion law.

  12. Sensitivity of EAS measurements to the energy spectrum of muons

    NASA Astrophysics Data System (ADS)

    Espadanal, J.; Cazon, L.; Conceição, R.

    2017-01-01

    We have studied how the energy spectrum of muons at production affects some of the most common measurements related to muons in extensive air shower studies, namely, the number of muons at the ground, the slope of the lateral distribution of muons, the apparent muon production depth, and the arrival time delay of muons at ground. We found that by changing the energy spectrum by an amount consistent with the difference between current models (namely EPOS-LHC and QGSJET-II.04), the muon surface density at ground increases 5% at 20° zenith angle and 17% at 60° zenith angle. This effect introduces a zenith angle dependence on the reconstructed number of muons which might be experimentally observed. The maximum of the muon production depth distribution at 40° increases ∼ 10 g/cm2 and ∼ 0 g/cm2 at 60°, which, from pure geometrical considerations, increases the arrival time delay of muons. There is an extra contribution to the delay due to the subluminal velocities of muons of the order of ∼ 3 ns at all zenith angles. Finally, changes introduced in the logarithmic slope of the lateral density function are less than 2%.

  13. Neutrino masses, Majorons, and muon decay

    SciTech Connect

    Santamaria, A.; Bernabeu, J.; Pich, A.

    1987-09-01

    The contributions to the parameters xi, delta, rho, and eta in muon decay coming from double Majoron emission, Majorana neutrino masses, and effects of charged scalars are evaluated in the scalar-triplet model. The relevance of these effects for planned experiments is discussed.

  14. ICOOL: A TOOL FOR MUON COLLIDER SIMULATIONS.

    SciTech Connect

    FERNOW,R.C.

    2001-09-28

    Current ideas for designing neutrino factories [ 1,2] and muon colliders [3] require unique configurations of fields and materials to prepare the muon beam for acceleration. This so-called front end system must accomplish the goals of phase rotation, bunching and cooling. We have continued the development of a 3-D tracking code, ICOOL [4], for examining possible muon collider front end configurations. A system is described in terms of a series of longitudinal regions with associated material and field properties. The tracking takes place in a coordinate system that follows a reference orbit through the system. The code takes into account decays and interactions of {approx}50-500 MeV/c muons in matter. Material geometry regions include cylinders and wedges. A number of analytic models are provided for describing the field configurations. Simple diagnostics are built into the code, including calculation of emittances and correlations, longitudinal traces, histograms and scatter plots. A number of auxiliary codes can be used for pre-processing, post-processing and optimization.

  15. Muon Acceleration Concepts for Future Neutrino Factory

    SciTech Connect

    Bogacz, Slawomir Alex

    2016-05-01

    Here, we summarize current state of concept for muon acceleration aimed at future Neutrino Factory. The main thrust of these studies was to reduce the overall cost while maintaining performance through exploring interplay between complexity of the cooling systems and the acceptance of the accelerator complex. To ensure adequate survival of the short-lived muons, acceleration must occur at high average gradient. The need for large transverse and longitudinal acceptances drives the design of the acceleration system to initially low RF frequency, e.g. 325 MHz, and then increased to 650 MHz, as the transverse size shrinks with increasing energy. High-gradient normal conducting RF cavities at these frequencies require extremely high peak-power RF sources. Hence superconducting RF (SRF) cavities are chosen. Here, we considered two cost effective schemes for accelerating muon beams for a stagable Neutrino Factory: Exploration of the so-called 'dual-use' linac concept, where the same linac structure is used for acceleration of both H- and muons and alternatively, the SRF efficient design based on multi-pass (4.5) 'dogbone' RLA, extendable to multi-pass FFAG-like arcs.

  16. Reconstruction of muon tracks in a buried plastic scintillator muon telescope (BATATA)

    NASA Astrophysics Data System (ADS)

    Riggi, S.; Insolia, A.; Medina-Tanco, G.; Trovato, E.

    2012-10-01

    The BATATA muon counter was designed as one of the foreseen detector upgrades of the Pierre Auger Observatory with the main goal of quantifying the electromagnetic contamination of the muon signal as a function of the depth for cosmic ray shower energies above 10 PeV. Nevertheless BATATA offers also the possibility of measuring the incoming direction of secondary muons from both GeV and PeV primary cosmic rays. Large efforts have been already done to quantify from simulations the amount of the electromagnetic contamination and the expected muon identification performances. The present work is focused on the evaluation of the detector performances for muon track reconstruction. To this aim and in view of the detector installation in the field, expected to be completed by the first half of current year, we performed a GEANT4 end-to-end simulation of such device and set up a track reconstruction procedure. Typical results concerning achieved acceptance and angular resolution for muons are presented.

  17. Testing model energy spectra of charged particles produced in hadron interactions on the basis of atmospheric muons

    SciTech Connect

    Dedenko, L. G.; Roganova, T. M.; Fedorova, G. F.

    2015-10-15

    An original method for calculating the spectrum of atmospheric muons with the aid of the CORSIKA 7.4 code package and numerical integration is proposed. The first step consists in calculating the energy distribution of muons for various fixed energies of primary-cosmic-ray particles and within several chosen hadron-interaction models included in the CORSIKA 7.4 code package. After that, the spectrum of atmospheric muons is calculated via integrating the resulting distribution densities with the chosen spectrum of primary-cosmic-ray particles. The atmospheric-muon fluxes that were calculated on the basis of the SIBYLL 2.1, QGSJET01, and QGSJET II-04 models exceed the predictions of the wellknown Gaisser approximation of this spectrum by a factor of 1.5 to 1.8 in the range of muon energies between about 10{sup 3} and 10{sup 4} GeV.Under the assumption that, in the region of extremely highmuon energies, a dominant contribution to the muon flux comes from one to two generations of charged π{sup ±} and K{sup ±} mesons, the production rate calculated for these mesons is overestimated by a factor of 1.3 to 1.5. This conclusion is confirmed by the results of the LHCf and TOTEM experiments.

  18. Spallation backgrounds in Super-Kamiokande are made in muon-induced showers

    NASA Astrophysics Data System (ADS)

    Li, Shirley Weishi; Beacom, John F.

    2015-05-01

    Crucial questions about solar and supernova neutrinos remain unanswered. Super-Kamiokande has the exposure needed for progress, but detector backgrounds are a limiting factor. A leading component is the beta decays of isotopes produced by cosmic-ray muons and their secondaries, which initiate nuclear spallation reactions. Cuts of events after and surrounding muon tracks reduce this spallation decay background by ≃ 90 % (at a cost of ≃ 20 % deadtime), but its rate at 6-18 MeV is still dominant. A better way to cut this background was suggested in a Super-Kamiokande paper by Bays et al. [Phys. Rev. D 85, 052007 (2012)] on a search for the diffuse supernova neutrino background. They found that spallation decays above 16 MeV were preceded near the same location by a peak in the apparent Cherenkov light profile from the muon; a more aggressive cut was applied to a limited section of the muon track, leading to decreased background without increased deadtime. We put their empirical discovery on a firm theoretical foundation. We show that almost all spallation decay isotopes are produced by muon-induced showers and that these showers are rare enough and energetic enough to be identifiable. This is the first such demonstration for any detector. We detail how the physics of showers explains the peak in the muon Cherenkov light profile and other Super-K observations. Our results provide a physical basis for practical improvements in background rejection that will benefit multiple studies. For solar neutrinos, in particular, it should be possible to dramatically reduce backgrounds at energies as low as 6 MeV.

  19. Mu2e: a Muon to Electron Conversion Experiment at Fermilab

    NASA Astrophysics Data System (ADS)

    Brown, David

    2014-03-01

    We present the status of Mu2e, a proposed experiment to measure the rate of muon to electron conversion in the field of a nucleus. The Mu2e experiment will be hosted by Fermilab at a new muon campus, using a new beamline to deliver protons to the muon generation target. Mu2e will use a series of three solenoids to collect, transport, stop, and analyze the muons produced when the 8 GeV pulsed proton beam from the booster hits the tungsten production target. The 200 nsec wide proton pulse is designed to have a ratio of out-of-time to in-time protons better than 10-10, insuring a measurement time window of approximately 1 microsecond essentially free from beam pion background. A precision, low-mass straw tube tracker will measure electron momenta with a precision of 1/1000, allowing clean separation of the conversion signal from Decay In Orbit electrons, the principle experimental background. Extensive coverage of multi-layer scintillation counters will detect 99.99% of the cosmic muons which could generate fake signals. A crystal calorimeter will provide particle ID to further reduce backgrounds. Detailed simulations show a 3-year run with 7.56×1017 stopped muons will allow a Single Event Sensitivity of 2×10-17, allowing an estimated 90% confidence level sensitivity to R of 6×10-17, a four-orders of magnitude improvement over existing limits. The Mu2e schedule is technically limited, with commissioning beginning in 2019. Mu2e may also run at Project X with 10× higher luminosity using either an aluminum or titanium target after minimal upgrades.

  20. Measurements of Beam Cooling in Muon Ionization Cooling Experiment

    NASA Astrophysics Data System (ADS)

    Mohayai, Tanaz; Snopok, Pavel; Rogers, Chris; Neuffer, David; Muon Ionization Cooling Experiment Collaboration

    2017-01-01

    Cooled muon beams are essential for production of high-flux neutrino beams at the Neutrino Factory and high luminosity muon beams at the Muon Collider. The international Muon Ionization Cooling Experiment, MICE aims to demonstrate muon beam cooling through ionization energy loss of muons in material. The standard figure of merit for cooling in MICE is the transverse RMS emittance reduction and to measure this, the individual muon positions and momenta are reconstructed using scintillating-fiber tracking detectors, before and after a low-Z absorbing material. In this study, in addition to a preview on the standard measurement technique, an alternative technique is described, which is the measurement of phase-space density using the novel Kernel Density Estimation method. Work supported by the U.S. Department of Energy under contract No. DE - AC05 - 06OR23100.

  1. Atmospheric Neutrino Induced Muons in the MINOS Far Detector

    SciTech Connect

    Rahman, Aftabur Dipu

    2007-02-01

    detector to be able to distinguish the charge of the muons. The measured charge is used to test the rate of the neutrino to the anti-neutrino oscillations by measuring the neutrino induced muon charge ratio. Using the high resolution sample, the μ+ to μ- double charge ratio has been determined to be RCPT = R$data\\atop{μ-/μ+}$/R$MC\\atop{μ-/μ+}$ = 0.90$+0.24\\atop{-0.18}$(stat) ± 0.09(syst). With the uncertainties added in quadrature, the CPT double ratio is consistent with unity showing no indication for CPT violation.

  2. Neutron capture in the r-process

    SciTech Connect

    Surman, Rebecca; Mclaughlin, Gail C; Mumpower, Matthew; Hix, William Raphael; Jones, K. L.

    2010-01-01

    Recently we have shown that neutron capture rates on nuclei near stability significantly influence the r-process abundance pattern. We discuss the different mechanisms by which the abundance pattern is sensitive to the capture rates and identify key nuclei whose rates are of particular im- portance. Here we consider nuclei in the A = 130 and A = 80 regions.

  3. Design and commissioning of a high magnetic field muon spin relaxation spectrometer at the ISIS pulsed neutron and muon source.

    PubMed

    Lord, J S; McKenzie, I; Baker, P J; Blundell, S J; Cottrell, S P; Giblin, S R; Good, J; Hillier, A D; Holsman, B H; King, P J C; Lancaster, T; Mitchell, R; Nightingale, J B; Owczarkowski, M; Poli, S; Pratt, F L; Rhodes, N J; Scheuermann, R; Salman, Z

    2011-07-01

    The high magnetic field (HiFi) muon instrument at the ISIS pulsed neutron and muon source is a state-of-the-art spectrometer designed to provide applied magnetic fields up to 5 T for muon studies of condensed matter and molecular systems. The spectrometer is optimised for time-differential muon spin relaxation studies at a pulsed muon source. We describe the challenges involved in its design and construction, detailing, in particular, the magnet and detector performance. Commissioning experiments have been conducted and the results are presented to demonstrate the scientific capabilities of the new instrument.

  4. Design and commissioning of a high magnetic field muon spin relaxation spectrometer at the ISIS pulsed neutron and muon source

    SciTech Connect

    Lord, J. S.; McKenzie, I.; Baker, P. J.; Cottrell, S. P.; Giblin, S. R.; Hillier, A. D.; Holsman, B. H.; King, P. J. C.; Nightingale, J. B.; Pratt, F. L.; Rhodes, N. J.; Blundell, S. J.; Lancaster, T.; Good, J.; Mitchell, R.; Owczarkowski, M.; Poli, S.; Scheuermann, R.; Salman, Z.

    2011-07-15

    The high magnetic field (HiFi) muon instrument at the ISIS pulsed neutron and muon source is a state-of-the-art spectrometer designed to provide applied magnetic fields up to 5 T for muon studies of condensed matter and molecular systems. The spectrometer is optimised for time-differential muon spin relaxation studies at a pulsed muon source. We describe the challenges involved in its design and construction, detailing, in particular, the magnet and detector performance. Commissioning experiments have been conducted and the results are presented to demonstrate the scientific capabilities of the new instrument.

  5. Observation of muon intensity variations by season with the MINOS far detector

    SciTech Connect

    Adamson, P.; Andreopoulos, C.; Arms, K.E.; Armstrong, R.; Auty, D.J.; Ayres, D.S.; Backhouse, C.; Barnett, J.; Barr, G.; Barrett, W.L.; Becker, B.R.; /Minnesota U. /Brookhaven

    2009-09-01

    The temperature of the upper atmosphere affects the height of primary cosmic ray interactions and the production of high-energy cosmic ray muons which can be detected deep underground. The MINOS far detector at Soudan MN, USA, has collected over 67 million cosmic ray induced muons. The underground muon rate measured over a period of five years exhibits a 4% peak-to-peak seasonal variation which is highly correlated with the temperature in the upper atmosphere. The coefficient, {alpha}{sub T}, relating changes in the muon rate to changes in atmospheric temperature was found to be: {alpha}{sub T} = 0.874 {+-} 0.009 (stat.) {+-} 0.010$ (syst.). Pions and kaons in the primary hadronic interactions of cosmic rays in the atmosphere contribute differently to {alpha}{sub T} due to the different masses and lifetimes. This allows the measured value of {alpha}{sub T} to be interpreted as a measurement of the K{pi} ratio for E{sub p}/unit[7](TeV) of $0.13 {+-} 0.08, consistent with the expectation from collider experiments.

  6. Studies of a Gas-filled Helical Muon Beam Cooling Channel

    SciTech Connect

    R.P. Johnson; K. Paul; T.J. Roberts; Y.S. Derbenev; K. Yonehara

    2006-06-26

    A helical cooling channel (HCC) can quickly reduce the six dimensional phase space of muon beams for muon colliders, neutrino factories, and intense muon sources. The HCC is composed of solenoidal, helical dipole, and helical quadrupole magnetic fields to provide the focusing and dispersion needed for emittance exchange as the beam follows an equilibrium helical orbit through a continuous homogeneous absorber. We consider liquid helium and liquid hydrogen absorbers in HCC segments that alternate with RF accelerating sections and we also consider gaseous hydrogen absorber in pressurized RF cavities imbedded in HCC segments. In the case of liquid absorber, the possibility of using superconducting RF in low magnetic field regions between the HCC segments may provide a cost effective solution to the high repetition rate needed for an intense neutrino factory or high average luminosity muon collider. In the gaseous hydrogen absorber case, the pressurized RF cavities can be operated at low temperature to improve their efficiency for higher repetition rates. Numerical simulations are used to optimize and compare the liquid and gaseous HCC techniques.

  7. Forward muon system for the D/Ø detector upgrade

    NASA Astrophysics Data System (ADS)

    Abramov, V.; Alexeev, G.; Babintsev, V.; Baldin, B.; Butler, J.; Beutel, D.; Bezzubov, V.; Bojko, N.; Burtovoi, V.; Chekulaev, S.; Chi, E.; Denisov, D.; Denisov, S.; Diehl, T.; Dodonov, V.; Dyshkant, A.; Eroshin, O.; Evdokimov, V.; Galyaev, A.; Goncharov, P.; Gornushkin, Yu.; Green, D.; Gurzhiev, S.; Haggerty, H.; Hanlet, P.; Hansen, S.; Hedin, D.; Ito, A.; Johns, K.; Kalinin, A.; Kostritskiy, A.; Kozelov, A.; Kozlovski, E.; Leitner, R.; Lokajíček, M.; Los, S.; Malyshev , V.; Mayorov, A.; Medovikov, V.; Mokhov, N.; Nozdrin, A.; Pisarev, I.; Pospíšil, S.; Raskowski, J.; Sabirov, B.; Šimák, V.; Smith, G.; Stefanik, A.; Stoianova, D.; Suk, M.; Tokmenin, V.; Vaniov, V.; Volkov, A.; Vorobiev, A.; Vrba, V.; Williams, R.; Wood, D.; Yatsunenko, Yu.; Yoffe, F.; Zimin, S.

    1998-12-01

    The design and main parameters of the completly redesigned DØ Forward Angle MUon System (FAMUS: 1.0<| η|<2.0) for the next high luminosity Tevatron Collider run are reported. Results of the studies of trigger scintillation counters based on fast scintillator Bicron 404A and WLS bars SOFZ-105 are presented. We report about results of test beam studies of prototype counters including minimum ionizing particles detection efficiency, time resolution and amplitude response. Radiation ageing of scintillating materials for the doses up to 1 Mrad, phototubes magnetic shielding in the fields of up to 700 G and ageing of phototubes are presented. Mini-Drift Tubes (MDTs) are chosen as FAMUS tracking detectors. The detector is a drift wire chamber with a metallic cathode. The detector operates in proportional mode with a fast freon-methane gas mixture to provide high drift velocity, adequate counting rate and low ageing. A description of the performance of the MDT is given. Studies of two prototypes in test beams were performed at FNAL and JINR. Obtained coordinate accuracy is around 0.5 mm r.m.s. All tests show robustness of MDT as tracking detector of the new muon system for a long period in high DØ background radiation conditions.

  8. Does the specific time of day used to capture data on ventilator-days have an impact on the documented rates of ventilator-associated pneumonia?

    PubMed

    Talbot, Thomas R; Starmer, John M

    2010-05-01

    Definitions of ventilator-associated pneumonia do not note a preferred daily time for obtaining denominator data. We examined collecting data on the number of ventilator-days at different times of day in 7 intensive care units. Rates of ventilator-associated pneumonia did not significantly differ when denominator data were collected at midnight, 8 am, or 4 pm, supporting standard definitions.

  9. Frequency Drift Rate Investigation of Solar Radio Burst Type II Due to Coronal Mass Ejections Occurrence on 4th November 2015 Captured by CALLISTO at Sumedang-Indonesia

    NASA Astrophysics Data System (ADS)

    Batubara, M.; Manik, T.; Suryana, R.; Lathif, M.; Sitompul, P.; Zamzam, M.; Mumtahana, F.

    2017-03-01

    The formations type of solar radio bursts can be known base on the frequency range that is detected. The CALLISTO system works with a wide band of the frequency making it possible to detect several types of solar burst. Indonesia exactly at Sumedang, CALLISTO system detected the formation of solar radio bursts forms of type II for the first time on 5 November 2014. On the other side, CALLISTO spectrometer detects and traces the phenomenon of CME (Coronal Mass Ejections) which causes the solar radio burst type II occurrence. In this paper will be calculated frequency drift rate during the occurrence of solar radio bursts of type II phenomenon on 4th November 2015 at 03:30 UT. The results of these calculations will be discussed as a related study of drift rate during the phenomenon of burst type II radio bursts associated with CME. The obtained drift rate during the solar radio bursts events above 2.8 MHz / s with low drift rate so that the speed of the CME that occurred only about 790 km / s as shown from LASCO.

  10. Imaging a vertical shaft from a tunnel using muons

    NASA Astrophysics Data System (ADS)

    Bonal, N.; Preston, L. A.; Dorsey, D. J.; Schwellenbach, D.; Green, A.; Smalley, D.

    2015-12-01

    We use muon technology to image a vertical shaft from a tunnel. The density of the materials through which cosmic ray muons pass influences the flux of muons because muons are more attenuated by higher density material. Additionally, muons can travel several kilometers allowing measurements through deep rock. Density maps are generated from muon flux measurements to locate subsurface features like tunnel structures and ore bodies. Additionally, muon data can be jointly inverted with other data such as gravity and seismic to produce higher quality earth models than produced from a single method. We collected several weeks of data in a tunnel to image a vertical shaft. The minimum length of rock between the vertical shaft and the detector is 120 meters and the diameter of the vertical shaft is 4.6 meters. The rock the muons traveled through consists of Tertiary age volcanic tuff and steeply dipping, small-displacement faults. Results will be presented for muon flux in the tunnel and Monte-Carlo simulations of this experiment. Simulations from both GEANT4 (Geometry And Tracking version 4) and MCNP6 (Monte-Carlo N-Particle version 6) models will be compared. The tunnel overburden from muon measurements is also estimated and compared with actual the overburden. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  11. Study of the Production of Radioactive Isotopes through Cosmic Muon Spallation in KamLAND

    SciTech Connect

    KamLAND Collaboration; Abe, S.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Nakamura, M.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Terashima, A.; Watanabe, H.; Yonezawa, E.; Yoshida, S.; Kozlov, A.; Murayama, H.; Busenitz, J.; Classen, T.; Grant, C.; Keefer, G.; Leonard, D. S.; McKee, D.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Gray, F.; Guardincerri, E.; Hsu, L.; Ichimura, K.; Kadel, R.; Lendvai, C.; Luk, K.-B.; O'Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D. A.; Jillings, C.; Mauger, C.; McKeown, R. D.; Vogel, P.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Piquemal, F.; Ricol, J.-S.; Decowski, M. P.

    2009-06-30

    Radioactive isotopes produced through cosmic muon spallation are a background for rare event detection in {nu} detectors, double-beta-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of {sup 11}C. Data from the Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillator, and for checking estimates from current simulations based upon MUSIC, FLUKA, and Geant4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be (2.8 {+-} 0.3) x 10{sup -4} n/({mu} {center_dot} (g/cm{sup 2})). For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment.

  12. Production of radioactive isotopes through cosmic muon spallation in KamLAND

    SciTech Connect

    Abe, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Kibe, Y.; Kishimoto, Y.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, M.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Terashima, A.; Watanabe, H.

    2010-02-15

    Radioactive isotopes produced through cosmic muon spallation are a background for rare-event detection in nu detectors, double-beta-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of {sup 11}C. Data from the Kamioka liquid-scintillator antineutrino detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillators, and for checking estimates from current simulations based upon MUSIC, FLUKA, and GEANT4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be Y{sub n}=(2.8+-0.3)x10{sup -4} mu{sup -1} g{sup -1} cm{sup 2}. For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment.

  13. Trigger electronics upgrade of PHENIX muon tracker

    NASA Astrophysics Data System (ADS)

    Adachi, S.; Akiyama, T.; Aoki, K.; Asano, H.; Ebesu, S.; Fukao, Y.; Haki, Y.; Hata, M.; Ichikawa, Y.; Iinuma, H.; Ikeda, Y.; Ikeno, M.; Imai, K.; Imazu, Y.; Karatsu, K.; Kasai, M.; Kawamura, H.; Kim, E.; Kurita, K.; Mibe, T.; Murakami, T.; Murata, J.; Nakagawa, I.; Nakamura, K. R.; Nakanishi, R.; Ninomiya, K.; Nitta, M.; Ogawa, N.; Onishi, J.; Park, S.; Sada, Y.; Saito, N.; Sameshima, R.; Sasaki, O.; Sato, A.; Seitaibashi, E.; Senzaka, K.; Shoji, K.; Taketani, A.; Tanida, K.; Toyoda, T.; Watanabe, K.

    2013-03-01

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) offers the unique capability to collide polarized protons at high energies. One of the highlights of the polarized proton program performed at √{s}=500 GeV is that it affords the direct measurement of sea quark contribution to the proton spin via W-boson production through the measurement of the parity violating single spin asymmetry. A new trigger electronics system for forward muons, which is especially capable of W-boson detection, was developed for the PHENIX experiment. The trigger was installed as an additional electronic circuit, and it was connected in parallel with the existing cathode readout electronics of the muon tracking chamber.

  14. Muon acceleration in cosmic-ray sources

    SciTech Connect

    Klein, Spencer R.; Mikkelsen, Rune E.; Becker Tjus, Julia

    2013-12-20

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in gamma-ray bursts, magnetars, or other sources. These transient sources have short lifetimes, which necessitate very high accelerating gradients, up to 10{sup 13} keV cm{sup –1}. At gradients above 1.6 keV cm{sup –1}, muons produced by hadronic interactions undergo significant acceleration before they decay. This muon acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. Using the IceCube high-energy diffuse neutrino flux limits, we set two-dimensional limits on the source opacity and matter density, as a function of accelerating gradient. These limits put strong constraints on different models of particle acceleration, particularly those based on plasma wake-field acceleration, and limit models for sources like gamma-ray bursts and magnetars.

  15. The MUon Scattering Experiment (MUSE) at PSI

    NASA Astrophysics Data System (ADS)

    Kohl, Michael; MUSE Collaboration

    2016-09-01

    The proton is not an elementary particle but has a substructure governed by the interaction of quarks and gluons. The size of the proton is manifest in the spatial distributions of the electric charge and magnetization, which determine the response to electromagnetic interaction. Recently, contradictory measurements of the proton charge radius between muonic hydrogen and electronic probes have constituted the proton radius puzzle, which has been challenging our basic understanding of the proton. The MUon Scattering Experiment (MUSE) in preparation at the Paul-Scherrer Institute (PSI) has the potential to resolve the puzzle by measuring the proton charge radius with electron and muon scattering simultaneously and with high precision, including any possible difference between the two, and with both beam charges. The status of the MUSE experiment will be reported. Supported by NSF and DOE.

  16. Helical Muon Beam Cooling Channel Engineering Design

    SciTech Connect

    Kashikhin, V.S.; Lopes, M.L.; Romanov, G.V.; Tartaglia, M.A.; Yonehara, K.; Yu, M.; Zlobin, A.V.; Flanagan, G.; Johnson, R.P.; Kazakevich, G.M.; Marhauser, F.; /MUONS Inc., Batavia

    2012-05-01

    The Helical Cooling Channel (HCC), a novel technique for six-dimensional (6D) ionization cooling of muon beams, has shown considerable promise based on analytic and simulation studies. However, the implementation of this revolutionary method of muon cooling requires new techniques for the integration of hydrogen-pressurized, high-power RF cavities into the low-temperature superconducting magnets of the HCC. We present the progress toward a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb{sub 3}Sn based HCC test section. We include discussions on the pressure and thermal barriers needed within the cryostat to maintain operation of the magnet at 4.2 K while operating the RF and energy absorber at a higher temperature. Additionally, we include progress on the Nb{sub 3}Sn helical solenoid design.

  17. Flux modulations seen by the muon veto of the GERDA experiment

    NASA Astrophysics Data System (ADS)

    GERDA Collaboration; Agostini, M.; Allardt, M.; Bakalyarov, A. M.; Balata, M.; Barabanov, I.; Barros, N.; Baudis, L.; Bauer, C.; Becerici-Schmidt, N.; Bellotti, E.; Belogurov, S.; Belyaev, S. T.; Benato, G.; Bettini, A.; Bezrukov, L.; Bode, T.; Borowicz, D.; Brudanin, V.; Brugnera, R.; Caldwell, A.; Cattadori, C.; Chernogorov, A.; D'Andrea, V.; Demidova, E. V.; di Vacri, A.; Domula, A.; Doroshkevich, E.; Egorov, V.; Falkenstein, R.; Fedorova, O.; Freund, K.; Frodyma, N.; Gangapshev, A.; Garfagnini, A.; Grabmayr, P.; Gurentsov, V.; Gusev, K.; Hegai, A.; Heisel, M.; Hemmer, S.; Hofmann, W.; Hult, M.; Inzhechik, L. V.; Ioannucci, L.; Janicsk'o Cs'athy, J.; Jochum, J.; Junker, M.; Kazalov, V.; Kihm, T.; Kirpichnikov, I. V.; Kirsch, A.; Klimenko, A.; Knapp, M.; Knöpfle, K. T.; Kochetov, O.; Kornoukhov, V. N.; Kuzminov, V. V.; Laubenstein, M.; Lazzaro, A.; Lebedev, V. I.; Lehnert, B.; Liao, H. Y.; Lindner, M.; Lippi, I.; Lubashevskiy, A.; Lubsandorzhiev, B.; Lutter, G.; Macolino, C.; Majorovits, B.; Maneschg, W.; Medinaceli, E.; Misiaszek, M.; Moseev, P.; Nemchenok, I.; Palioselitis, D.; Panas, K.; Pandola, L.; Pelczar, K.; Pullia, A.; Riboldi, S.; Ritter, F.; Rumyantseva, N.; Sada, C.; Salathe, M.; Schmitt, C.; Schneider, B.; Schönert, S.; Schreiner, J.; Schütz, A.-K.; Schulz, O.; Schwingenheuer, B.; Selivanenko, O.; Shevchik, E.; Shirchenko, M.; Simgen, H.; Smolnikov, A.; Stanco, L.; Stepaniuk, M.; Strecker, H.; Vanhoefer, L.; Vasenko, A. A.; Veresnikova, A.; von Sturm, K.; Wagner, V.; Walter, M.; Wegmann, A.; Wester, T.; Wiesinger, C.; Wilsenach, H.; Wojcik, M.; Yanovich, E.; Zhitnikov, I.; Zhukov, S. V.; Zinatulina, D.; Zuber, K.; Zuzel, G.

    2016-11-01

    The GERDA experiment at LNGS of INFN is equipped with an active muon veto. The main part of the system is a water Cherenkov veto with 66 PMTs in the water tank surrounding the GERDA cryostat. The muon flux recorded by this veto shows a seasonal modulation. Two causes have been identified: (i) secondary muons from the CNGS neutrino beam (2.2%) and (ii) a temperature modulation of the atmosphere (1.4%). A mean cosmic muon rate of Iμ0 =(3.477 ± 0 .002stat ± 0 .067sys) ×10-4 /(s · m2) was found in good agreement with other experiments at LNGS. Combining the present result with those from previous experiments at LNGS the effective temperature coefficient αT , Lngs is determined to 0.93 ± 0.03. A fit of the temperature coefficients measured at various underground sites yields a kaon to pion ratio rK/π of 0.10 ± 0.03.

  18. Tapered channel for six-dimensional muon cooling towards micron-scale emittances

    NASA Astrophysics Data System (ADS)

    Stratakis, Diktys; Fernow, Richard C.; Berg, J. Scott; Palmer, Robert B.

    2013-09-01

    A high-luminosity muon collider requires a significant reduction of the six-dimensional emittance prior to acceleration. Obtaining the desired final emittances requires transporting the muon beam through long sections of a beam channel containing rf cavities, absorbers, and focusing solenoids. Here we propose a new scheme to improve the performance of the channel, consequently increasing the number of transmitted muons and the lattice cooling efficiency. The key idea of our scheme is to tune progressively the main lattice parameters, such as the cell dimensions, rf frequency, and coil strengths, while always keeping the beam emittance significantly above the equilibrium value. We adopt this approach for a new cooling lattice design for a muon collider, and examine its performance numerically. We show that with tapering the cooling rate is not only higher than conventional designs, but also maintains its performance through the channel, resulting in a notable 6D emittance decrease by 3 orders of magnitude. We also review important lattice parameters, such as the required focusing fields, absorber length, cavity frequency, and voltage.

  19. Recent results from COMPASS muon scattering measurements

    NASA Astrophysics Data System (ADS)

    Capozza, Luigi; Compass Collaboration

    2012-10-01

    A sample of recent results in muon scattering measurements from the COMPASS experiment at CERN will be reviewed. These include high energy processes with longitudinally polarised proton and deuteron targets. High energy polarised measurements provide important constraints for studying the nucleon spin structure and thus permit to test the applicability of the theoretical framework of factorisation theorems and perturbative QCD. Specifically, latest results on longitudinal quark polarisation, quark helicity densities and gluon polarisation will be reviewed.

  20. Seasonal modulations of the underground cosmic-ray muon energy

    SciTech Connect

    Malgin, A. S.

    2015-08-15

    The parameters of the seasonal modulations in the intensity of muons and cosmogenic neutrons generated by them at a mean muon energy of 280 GeV have been determined in the LVD (Large Volume Detector) experiment. The modulations of muons and neutrons are caused by a temperature effect, the seasonal temperature and density variations of the upper atmospheric layers. The analysis performed here leads to the conclusion that the variations in the mean energy of the muon flux are the main source of underground cosmogenic neutron variations, because the energy of muons is more sensitive to the temperature effect than their intensity. The parameters of the seasonal modulations in the mean energy of muons and the flux of cosmogenic neutrons at the LVD depth have been determined from the data obtained over seven years of LVD operation.

  1. SSC detector muon sub-system beam tests

    SciTech Connect

    Downing, R.; Errede, S.; Gauthier, A.; Haney, M.; Karliner, I.; Liss, T.; O`Halloran, T.; Sheldon, P.; Simiatis, V.; Thaler, J.; Wiss, J.; Green, D.; Martin, P.; Morfin, J.; Kunori, S.; Skuja, A.; Okusawa, T.; Takahashi, T.; Teramoto, Y.; Yoshida, T.; Asano, Y.; Mann, T.; Davisson, R.; Liang, G.; Lubatti, H.; Wilkes, R.; Zhao, T.; Carlsmith, D.

    1993-08-01

    We propose to start a test-beam experiment at Fermilab studying the problems associated with tracking extremely high energy muons through absorbers. We anticipate that in this energy range the observation of the muons will be complicated by associated electromagnetic radiation Monte Carlo simulations of this background need to be tuned by direct observations. These beam tests are essential to determine important design parameters of a SSC muon detector, such as the choice of the tracking, geometry, hardware triggering schemes, the number of measuring stations, the amount of iron between measuring stations, etc. We intend to begin the first phase of this program in November of 1990 utilizing the Tevatron muon beam. We plan to measure the multiplicity, direction, and separation of secondary particles associated with the primary muon track as it emerges from an absorber. The second phase of beam test in 1992 or later will be a full scale test for the final design chosen in our muon subsystem proposal.

  2. Analytical calculation of muon intensities under deep sea-water

    NASA Technical Reports Server (NTRS)

    Inazawa, H.; Kobayakawa, K.

    1985-01-01

    The study of the energy loss of high energy muons through different materials, such as rock and sea-water can cast light on characteristics of lepton interactions. There are less ambiguities for the values of atomic number (Z) and mass number (A) in sea-water than in rock. Muon intensities should be measured as fundamental data and as background data for searching the fluxes of neutrino. The average range energy relation in sea-water is derived. The correction factors due to the range fluctuation is also computed. By applying these results, the intensities deep under sea are converted from a given muon energy spectra at sea-level. The spectra of conventional muons from eta, K decays have sec theta enhancement. The spectrum of prompt muons from charmed particles is almost isotropic. The effect of prompt muons is examined.

  3. Muon Beam Helical Cooling Channel Design

    SciTech Connect

    Johnson, Rolland; Ankenbrandt, Charles; Flanagan, G; Kazakevich, G M; Marhauser, Frank; Neubauer, Michael; Roberts, T; Yoshikawa, C; Derbenev, Yaroslav; Morozov, Vasiliy; Kashikhin, V S; Lopes, Mattlock; Tollestrup, A; Yonehara, Katsuya; Zloblin, A

    2013-06-01

    The Helical Cooling Channel (HCC) achieves effective ionization cooling of the six-dimensional (6d) phase space of a muon beam by means of a series of 21st century inventions. In the HCC, hydrogen-pressurized RF cavities enable high RF gradients in strong external magnetic fields. The theory of the HCC, which requires a magnetic field with solenoid, helical dipole, and helical quadrupole components, demonstrates that dispersion in the gaseous hydrogen energy absorber provides effective emittance exchange to enable longitudinal ionization cooling. The 10-year development of a practical implementation of a muon-beam cooling device has involved a series of technical innovations and experiments that imply that an HCC of less than 300 m length can cool the 6d emittance of a muon beam by six orders of magnitude. We describe the design and construction plans for a prototype HCC module based on oxygen-doped hydrogen-pressurized RF cavities that are loaded with dielectric, fed by magnetrons, and operate in a superconducting helical solenoid magnet.

  4. Recent Innovations in Muon Beam Cooling

    SciTech Connect

    Johnson, Rolland P.; Alsharo'a, Mohammad; Hanlet, Pierrick M.; Hartline, Robert; Kuchnir, Moyses; Paul, Kevin; Roberts, Thomas J.; Ankenbrandt, Charles; Barzi, Emanuela; Del Frate, Licia; Gonin, Ivan; Moretti, Alfred; Neuffer, David; Popovic, Milorad; Romanov, Gennady; Turrioni, Daniele; Yarba, Victor; Beard, Kevin; Bogacz, S. Alex; Derbenev, Yaroslav

    2006-03-20

    Eight new ideas are being developed under SBIR/STTR grants to cool muon beams for colliders, neutrino factories, and muon experiments. Analytical and simulation studies have confirmed that a six-dimensional (6D) cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas can provide effective beam cooling. This helical cooling channel (HCC) has solenoidal, helical dipole, helical quadrupole, and helical sextupole magnetic fields to generate emittance exchange and achieve 6D emittance reduction of over 3 orders of magnitude in a 100 m segment. Four such sequential HCC segments, where the RF frequencies are increased and transverse physical dimensions reduced as the beams become cooler, implies a 6D emittance reduction of almost five orders of magnitude. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, then can be employed to reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that can be used as MANX, an exceptional 6D cooling demonstration experiment.

  5. Muon g-2 Experiment at Fermilab

    SciTech Connect

    Gray, Frederick

    2015-10-01

    A new experiment at Fermilab will measure the anomalous magnetic moment of the muon with a precision of 140 parts per billion (ppb). This measurement is motivated by the results of the Brookhaven E821 experiment that were first released more than a decade ago, which reached a precision of 540 ppb. As the corresponding Standard Model predictions have been refined, the experimental and theoretical values have persistently differed by about 3 standard deviations. If the Brookhaven result is confirmed at Fermilab with this improved precision, it will constitute definitive evidence for physics beyond the Standard Model. The experiment observes the muon spin precession frequency in flight in a well-calibrated magnetic field; the improvement in precision will require both 20 times as many recorded muon decay events as in E821 and a reduction by a factor of 3 in the systematic uncertainties. This paper describes the current experimental status as well as the plans for the upgraded magnet, detector and storage ring systems that are being prepared for the start of beam data collection in 2017.

  6. Applications of Cosmic Ray Muon Radiography

    NASA Astrophysics Data System (ADS)

    Guardincerri, E.; Durham, J. M.; Morris, C. L.; Rowe, C. A.; Poulson, D. C.; Bacon, J. D.; Plaud-Ramos, K.; Morley, D. J.

    2015-12-01

    The Dome of Santa Maria del Fiore, Florence Cathedral, was built between 1420 and 1436 by architect Filippo Brunelleschi and it is now cracking under its own weight. Engineering efforts are underway to model the dome's structure and reinforce it against further deterioration. According to some scholars, Brunelleschi might have built reinforcement structures into the dome itself; however, the only confirmed known subsurface reinforcement is a chain of iron and stone around the dome's base. Tomography with cosmic ray muons is a non-destructive imaging method that can be used to image the interior of the wall and therefore ascertain the layout and status of any iron substructure in the dome. We will show the results from a muon tomography measurement of iron hidden in a mockup of the dome's wall performed at Los Alamos National Lab in 2015. The sensitivity of this technique, and the status of this project will be also discussed. At last, we will show results on muon attenuation radiography of larger shallow targets.

  7. Next Generation Muon g-2 Experiments

    SciTech Connect

    Hertzog, David W.

    2015-12-02

    I report on the progress of two new muon anomalous magnetic moment experiments, which are in advanced design and construction phases. The goal of Fermilab E989 is to reduce the experimental uncertainty of $a_\\mu$ from Brookhaven E821 by a factor of 4; that is, $\\delta a_\\mu \\sim 16 \\times 10^{-11}$, a relative uncertainty of 140~ppb. The method follows the same magic-momentum storage ring concept used at BNL, and pioneered previously at CERN, but muon beam preparation, storage ring internal hardware, field measuring equipment, and detector and electronics systems are all new or upgraded significantly. In contrast, J-PARC E34 will employ a novel approach based on injection of an ultra-cold, low-energy, muon beam injected into a small, but highly uniform magnet. Only a small magnetic focusing field is needed to maintain storage, which distinguishes it from CERN, BNL and Fermilab. E34 aims to roughly match the previous BNL precision in their Phase~1 installation.

  8. Recent Innovations in Muon Beam Cooling

    SciTech Connect

    Rolland P. Johnson; Mohammad Alsharo'a; Charles Ankenbrandt; Emanuela Barzi; Kevin Beard; S. Alex Bogacz; Yaroslav Derbenev; Licia Del Frate; Ivan Gonin; Pierrick M. Hanlet; Robert Hartline; Daniel M. Kaplan; Moyses Kuchnir; Alfred Moretti; David Neuffer; Kevin Paul; Milorad Popovic; Thomas J. Roberts; Gennady Romanov; Daniele Turrioni; Victor Yarba; and Katsuya Yonehara

    2006-03-01

    Eight new ideas are being developed under SBIR/STTR grants to cool muon beams for colliders, neutrino factories, and muon experiments. Analytical and simulation studies have confirmed that a six-dimensional (6D) cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas can provide effective beam cooling. This helical cooling channel (HCC) has solenoidal, helical dipole, helical quadrupole, and helical sextupole magnetic fields to generate emittance exchange and achieve 6D emittance reduction of over 3 orders of magnitude in a 100 m segment. Four such sequential HCC segments, where the RF frequencies are increased and transverse physical dimensions reduced as the beams become cooler, implies a 6D emittance reduction of almost five orders of magnitude. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, then can be employed to reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that can be used as MANX, an exceptional 6D cooling demonstration experiment.

  9. Measurement of the dmud quartet-to-doublet molecular formation rate ratio (lambdaq : lambdad) and the mu d hyperfine rate (lambdaqd) using the fusion neutrons from mu- stops in D2 gas

    NASA Astrophysics Data System (ADS)

    Raha, Nandita

    The MuSun experiment will determine the microd capture rate (micro - + d → n + n + nue) from the doublet hyperfine state Lambdad, of the muonic deuterium atom in the 1S ground state to a precision of 1.5%. Modern effective field theories (EFT) predict that an accurate measurement of Lambdad would determine the two-nucleon weak axial current. This will help in understanding all weak nuclear interactions such as the stellar thermonuclear proton-proton fusion reactions, the neutrino reaction nu + d (which explores the solar neutrino oscillation problem). It will also help us understand weak nuclear interactions involving more than two nucleons---double beta decay---as they do involve a two-nucleon weak axial current term. The experiment took place in the piE3 beam-line of Paul Scherrer Institute (PSI) using a muon beam generated from 2.2 mA proton beam---which is the highest intensity beam in the world. The muons first passed through entrance scintillator and multiwire proportional chamber for determining thier entrance timing and position respectively. Then they were stopped in a cryogenic time projection chamber (cryo-TPC) filled with D2 gas. This was surrounded by plastic scintillators and multiwire proportional chambers for detecting the decay electrons and an array of eight liquid scintillators for detecting neutrons. Muons in deuterium get captured to form microd atoms in the quartet and doublet spin states. These atoms undergo nuclear capture from these hyperfine states respectively. There is a hyperfine transition rate from quartet-to-doublet state---lambdaqd along with dmicrod molecular formation which further undergoes a fusion reaction with the muon acting as a catalyst (MCF). The goal of this dissertation is to measure the dmicro d quartet-to-doublet rate ratio (lambdaq : lambdad) and microd hyperfine rate (lambda qd) using the fusion neutrons from micro. stops in D2 gas. The dmicrod molecules undergo MCF reactions from the doublet and the quartet state

  10. Neutron captures and the r-process

    SciTech Connect

    Farouqi, K.; Kratz, K.-L.; Pfeiffer, B.; Rauscher, T.; Thielemann, F.-K.

    2006-03-13

    In order to study possible neutron-capture effects during an r-process, it is necessary to perform fully dynamical simulations. We have performed such calculations within the model of an adiabatically expanding high-entropy bubble of a SN II, using temperature-dependent reaction rates including the NON-SMOKER neutron-capture rates of Rauscher et al.

  11. Final Report: Part 1. In-Place Filter Testing Instrument for Nuclear Material Containers. Part 2. Canister Filter Test Standards for Aerosol Capture Rates.

    SciTech Connect

    Brown, Austin Douglas; Runnels, Joel T.; Moore, Murray E.; Reeves, Kirk Patrick

    2014-11-02

    ) fouling of o-rings, (B) leakage through simulated cracks in o-rings, and (C) air leakage due to inadequately tightened canister lids. The Los Alamos POC instrument determined pertinent air flow and pressure quantities, and this knowledge was used to specify a customized Isaac® (Z axis, Salt Lake City, UT) leak test module. The final Los Alamos IPFT (incorporating the Isaac® leak test module) was used to repeat the tests in the Instrument Development Plan (with simulated filter clogging tests and canister leak pathway tests). The Los Alamos IPFT instrument is capable of determining filter clogging and leak rate conditions, without requiring removal of the container lid. The IPFT measures pressure decay rate from 1.7E-03 in WC/sec to 1.7E-01 in WC/sec. On the same unit scale, helium leak testing of canisters has a range from 5.7E-07 in WC/sec to 1.9E-03 in WC/sec. For a 5-quart storage canister, the IPFT measures equivalent leak flow rates from 0.03 to 3.0 cc/sec. The IPFT does not provide the same sensitivity as helium leak testing, but is able to gauge the assembled condition of as-found and in-situ canisters.

  12. Muon Cooling R&D Progress in the US

    NASA Astrophysics Data System (ADS)

    Li, Derun

    2008-02-01

    Muon ionization cooling R&D is important for a neutrino factory and future muon collider. In addition to theoretical studies, much progress has been made in muon cooling channel hardware R&D since NuFact-2006. This paper reports the progress on hardware R&D that includes experimental RF test programs using 805-MHz RF cavity, superconducting (SC) solenoids (coupling coils), 201-MHz RF cavity, liquid hydrogen absorber and MUCOOL Test Area (MTA) experiment preparation for beam tests.

  13. Aligning the CMS muon chambers with the muon alignment system during an extended cosmic ray run

    NASA Astrophysics Data System (ADS)

    CMS Collaboration

    2010-03-01

    The alignment system for the muon spectrometer of the CMS detector comprises three independent subsystems of optical and analog position sensors. It aligns muon chambers with respect to each other and to the central silicon tracker. System commissioning at full magnetic field began in 2008 during an extended cosmic ray run. The system succeeded in tracking muon detector movements of up to 18 mm and rotations of several milliradians under magnetic forces. Depending on coordinate and subsystem, the system achieved chamber alignment precisions of 140-350 μm and 30-200 μrad, close to the precision requirements of the experiment. Systematic errors on absolute positions are estimated to be 340-590 μm based on comparisons with independent photogrammetry measurements.

  14. Muon SR Newsletter, No. 29, April 5, 1984

    SciTech Connect

    Crowe, K.M.; Portis, A.M.; Yamazaki, T.

    1984-04-05

    Muon SR stands for Muon Spin Relaxation, Rotation, Resonance, Research, or what have you. The intention of the mnemonic acronym is to draw attention to the analogy with NMR and ESR, the range of whose applications is well known. Any study of the interactions of the muon spin by virtue of the asymmetric decay is considered ..mu..SR, but this definition is not intended to exclude any peripherally related phenomena, especially if relevant to the use of the muon's mganetic moment as a delicate probe of matter. Abstracts of individual items from this issue were prepared separately for the data base.

  15. Toroidal magnetic detector for high resolution measurement of muon momenta

    DOEpatents

    Bonanos, Peter

    1992-01-01

    A muon detector system including central and end air-core superconducting toroids and muon detectors enclosing a central calorimeter/detector. Muon detectors are positioned outside of toroids and all muon trajectory measurements are made in a nonmagnetic environment. Internal support for each magnet structure is provided by sheets, located at frequent and regularly spaced azimuthal planes, which interconnect the structural walls of the toroidal magnets. In a preferred embodiment, the shape of the toroidal magnet volume is adjusted to provide constant resolution over a wide range of rapidity.

  16. Investigation into the feasibility of a soft muon experiment

    SciTech Connect

    Tincknell, M.L.

    1990-06-01

    Issues relevant in a soft ({lt} 5 GeV) muon pair experiment at the AGS or the RHIC central region are investigated. Observation of direct muon pairs is difficult because the muon pair to pion ratio is {omicron} (10{sup {minus}4}). Absorber penetration is the only means available to identify high energy muons among a large number of hadrons. Three important sources of background are sail-through hadrons that fail to interact in the absorber, the decays of pions and kaons to muons in the absorber, and leakage of hadronic shower products through the absorber. An absorber thick enough to limit the ratio of combinatorical background pairs to pions to {omicron} (10{sup {minus}4}) imposes a significant muon kinetic energy threshold due to muon range in the absorber. Absorbers with low atomic number Z are preferred to keep this threshold low, and to avoid loss of invariant mass resolution due to energy loss straggling and multiple coulomb scattering. Long-lived meson to muon decays can be directly suppressed only by picking an absorber with short interaction length, which implies a high density, high Z material. With sufficiently high statistics, a subtraction of the spectra of like-sign pairs from the spectrum of opposite-sign pairs should recover the direct muon pair spectrum. 9 refs., 9 figs., 2 tabs.

  17. The Muon system of the run II D0 detector

    SciTech Connect

    Abazov, V.M.; Acharya, B.S.; Alexeev, G.D.; Alkhazov, G.; Anosov, V.A.; Baldin, B.; Banerjee, S.; Bardon, O.; Bartlett, J.F.; Baturitsky, M.A.; Beutel, D.; Bezzubov, V.A.; Bodyagin, V.; Butler, J.M.; Cease, H.; Chi, E.; Denisov, D.; Denisov, S.P.; Diehl, H.T.; Doulas, S.; Dugad, S.R.; /Beijing, Inst. High Energy Phys. /Charles U. /Prague, Tech. U. /Prague, Inst. Phys. /San Francisco de Quito U. /Tata Inst. /Dubna, JINR /Moscow, ITEP /Moscow State U. /Serpukhov, IHEP /St. Petersburg, INP /Arizona U. /Florida State U. /Fermilab /Northern Illinois U. /Indiana U. /Boston U. /Northeastern U. /Brookhaven /Washington U., Seattle /Minsk, Inst. Nucl. Problems

    2005-03-01

    The authors describe the design, construction and performance of the upgraded D0 muon system for Run II of the Fermilab Tevatron collider. Significant improvements have been made to the major subsystems of the D0 muon detector: trigger scintillation counters, tracking detectors, and electronics. The Run II central muon detector has a new scintillation counter system inside the iron toroid and an improved scintillation counter system outside the iron toroid. In the forward region, new scintillation counter and tracking systems have been installed. Extensive shielding has been added in the forward region. A large fraction of the muon system electronics is also new.

  18. Imaging a nuclear reactor using cosmic ray muons

    SciTech Connect

    Perry, John; Azzouz, Mara; Bacon, Jeffrey; Borozdin, Konstantin; Chen, Elliott; Fabritius, Joseph II; Milner, Edward; Miyadera, Haruo; Morris, Christopher; Roybal, Jonathan; Wang, Zhehui; Busch, Bob; Carpenter, Ken; Hecht, Adam A.; Masuda, Koji; Spore, Candace; Toleman, Nathan; Aberle, Derek; Lukic, Zarija

    2013-05-14

    The passage of muons through matter is dominated by the Coulomb interaction with electrons and nuclei. The muon interaction with electrons leads to continuous energy loss and stopping of the muons. The muon interaction with nuclei leads to angular diffusion. We present experimental images of a nuclear reactor, the AGN-201M reactor at the University of New Mexico, using data measured with a particle tracker built from a set of sealed drift tubes. The data are compared with a geant4 model. In both the data and simulation, we identify specific regions corresponding to elements of the reactor structure, including its core, moderator, and shield.

  19. Toroidal magnetic detector for high resolution measurement of muon momenta

    DOEpatents

    Bonanos, P.

    1992-01-07

    A muon detector system including central and end air-core superconducting toroids and muon detectors enclosing a central calorimeter/detector. Muon detectors are positioned outside of toroids and all muon trajectory measurements are made in a nonmagnetic environment. Internal support for each magnet structure is provided by sheets, located at frequent and regularly spaced azimuthal planes, which interconnect the structural walls of the toroidal magnets. In a preferred embodiment, the shape of the toroidal magnet volume is adjusted to provide constant resolution over a wide range of rapidity. 4 figs.

  20. Muons probe magnetism and hydrogen interaction in graphene

    NASA Astrophysics Data System (ADS)

    Riccò, M.; Aramini, M.; Mazzani, M.; Pontiroli, D.; Gaboardi, M.; Yazyev, O. V.

    2013-12-01

    Muon spin resonance (μSR) is a powerful technique for investigating the local magnetic fields in materials through implanted muons. Here we report a μSR study of chemically produced thermally exfoliated graphene. Our results provide an experimental answer to the many theoretical investigations of magnetic properties of graphene. The observed muon spin precession is attributed to a localized muon-hydrogen nuclear dipolar interaction rather than to a hyperfine interaction with magnetic electrons. This proves the absence of magnetism in chemically produced thermally exfoliated graphene.

  1. Effect of acid-catalyzed formation rates of benzimidazole-linked polymers on porosity and selective CO2 capture from gas mixtures.

    PubMed

    Altarawneh, Suha; İslamoğlu, Timur; Sekizkardes, Ali Kemal; El-Kaderi, Hani M

    2015-04-07

    Benzimidazole-linked polymers (BILPs) are emerging candidates for gas storage and separation applications; however, their current synthetic methods offer limited control over textural properties which are vital for their multifaceted use. In this study, we investigate the impact of acid-catalyzed formation rates of the imidazole units on the porosity levels of BILPs and subsequent effects on CO2 and CH4 binding affinities and selective uptake of CO2 over CH4 and N2. Treatment of 3,3'-Diaminobenzidine tetrahydrochloride hydrate with 1,2,4,5-tetrakis(4-formylphenyl)benzene and 1,3,5-(4-formylphenyl)-benzene in anhydrous DMF afforded porous BILP-15 (448 m(2) g(-1)) and BILP-16 (435 m(2) g(-1)), respectively. Alternatively, the same polymers were prepared from the neutral 3,3'-Diaminobenzidine and catalytic amounts of aqueous HCl. The resulting polymers denoted BILP-15(AC) and BILP-16(AC) exhibited optimal surface areas; 862 m(2) g(-1) and 643 m(2) g(-1), respectively, only when 2 equiv of HCl (0.22 M) was used. In contrast, the CO2 binding affinity (Qst) dropped from 33.0 to 28.9 kJ mol(-1) for BILP-15 and from 32.0 to 31.6 kJ mol(-1) for BILP-16. According to initial slope calculations at 273 K/298 K, a notable change in CO2/N2 selectivity was observed for BILP-15(AC) (61/50) compared to BILP-15 (83/63). Similarly, ideal adsorbed solution theory (IAST) calculations also show the higher specific surface area of BILP-15(AC) and BILP-16(AC) compromises their CO2/N2 selectivity.

  2. Studies on Muon Induction Acceleration and an Objective Lens Design for Transmission Muon Microscope

    NASA Astrophysics Data System (ADS)

    Artikova, Sayyora; Yoshida, Mitsuhiro; Naito, Fujio

    Muon acceleration will be accomplished by a set of induction cells, where each increases the energy of the muon beam by an increment of up to 30 kV. The cells are arranged in a linear way resulting in total accelerating voltage of 300 kV. Acceleration time in the linac is about hundred nanoseconds. Induction field calculation is based on an electrostatic approximation. Beam dynamics in the induction accelerator is investigated and final beam focusing on specimen is realized by designing a pole piece lens.

  3. Development of the read-out ASIC for muon chambers

    NASA Astrophysics Data System (ADS)

    Atkin, E.; Bulbakov, I.; Gusev, A.; Malankin, E.; Normanov, D.; Sagdiev, I.; Shumikhin, V.; Shumkin, O.; Ivanov, P.; Vinogradov, S.; Voronin, A.; Samsonov, V.; Ivanov, V.

    2016-02-01

    A front-end prototype ASIC for muon chambers is presented. ASIC was designed and prototyped in the CMOS UMC MMRF 180 nm process via Europractice. The chip includes 8 analog processing channels, each consisting of a preamplifier, two shapers (fast and slow), differential comparator and an area efficient 6 bit SAR ADC with 1.2 mW power consumption at 50 Msps. The chip also includes the threshold DAC and digital serializer. The design has the following features: dynamic range of 100 fC, channel hit rate of 2 MHz, ENC of 1000 e- at 50 pF, power consumption of 10 mW per channel, 6 bit SAR ADC.

  4. Helical muon beam cooling channel engineering design

    SciTech Connect

    Johnson, Rolland

    2015-08-07

    The Helical Cooling Channel (HCC) achieves effective ionization cooling of the six-dimensional (6d) phase space of a muon beam by means of a series of 21st century inventions. In the HCC, hydrogen-pressurized RF cavities enable high RF gradients in strong external magnetic fields. The theory of the HCC, which requires a magnetic field with solenoid, helical dipole, and helical quadrupole components, demonstrates that dispersion in the gaseous hydrogen energy absorber provides effective emittance exchange to enable longitudinal ionization cooling. The 10-year development of a practical implementation of a muon-beam cooling device has involved a series of technical innovations and experiments that imply that an HCC of less than 300 m length can cool the 6d emittance of a muon beam by six orders of magnitude. We describe the design and construction plans for a prototype HCC module based on oxygen-doped hydrogen-pressurized RF cavities that are loaded with dielectric, fed by magnetrons, and operate in a superconducting helical solenoid magnet. The first phase of this project saw the development of a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb3Sn-based HS test section. Two very novel ideas are required to realize the design. The first idea is the use of dielectric inserts in the RF cavities to make them smaller for a given frequency so that the cavities and associated plumbing easily fit inside the magnet cryostat. Calculations indicate that heat loads will be tolerable, while RF breakdown of the dielectric inserts will be suppressed by the pressurized hydrogen gas. The second new idea is the use of a multi-layer Nb3Sn helical solenoid. The technology demonstrations for the two aforementioned key components of a 10T, 805 MHz HCC were begun in this project. The work load in the Fermilab Technical Division made it difficult to test a multi-layer Nb3Sn solenoid as originally planned. Instead, a complementary

  5. Generation of Runaway Electrons Induced by Cosmic-Ray Muons in Thunderstorm Electric Fields

    NASA Astrophysics Data System (ADS)

    Torii, T.; Nishijima, T.; Sugita, T.; Kawasaki, Z.

    2004-05-01

    Gamma ray dose-rate increases associated with winter thunderstorm activities have been observed in the coastal areas facing the Sea of Japan [1]. In order to investigate the generation of energetic photons which originate in thunderstorm electric fields, we have calculated the behavior of secondary cosmic ray electrons and photons in electric fields with Monte Carlo method. In the calculation, the electron and photon fluxes have increased greatly in the region where the field strength exceeds about 280 P(z) kV/m-atm, and these energy spectra show a large increase in the energy region up to several MeV [2]. In addition to the analysis of the electromagnetic component of cosmic rays, we have carried out the Monte Carlo transport calculations of the cosmic-ray muons and associated particles (e.g. knock-on electrons and bremsstrahlung photons) in thunderstorm electric fields, using GEANT4 code [3]. Muons form a large part of the secondary cosmic-rays and directly reach the regions of strong electric fields owing to their high penetrability in the atmosphere. Therefore, they can serve as the source of a considerable amount of runaway electrons, through their ionization process with air molecules, and their decay into energetic electrons. The electron and photon fluxes show notable increases in the strong electric field, while the muon flux does not fluctuate significantly. These results indicate that the production of energetic electrons by cosmic ray muons plays an important role in the enhancement of electron and photon fluxes in thunderstorm electric fields. Finally, we discuss a feasibility of muon-triggered lightning deduced from the muon transport calculation inside thunderstorm electric fields. From the calculation results, we estimate that the irradiation of muon beams rapidly increases energy deposition in the region of strong electric fields, and produce numerous electron - ion pairs. These productions may induce the lightning discharge by the runaway

  6. The EEE Project: a sparse array of telescopes for the measurement of cosmic ray muons

    NASA Astrophysics Data System (ADS)

    La Rocca, P.; Abbrescia, M.; Avanzini, C.; Baldini, L.; Baldini Ferroli, R.; Batignani, G.; Bencivenni, G.; Bossini, E.; Chiavassa, A.; Cicalò, C.; Cifarelli, L.; Coccetti, F.; Coccia, E.; Corvaglia, A.; De Gruttola, D.; De Pasquale, S.; Di Giovanni, A.; D'Incecco, M.; Dreucci, M.; Fabbri, F. L.; Fattibene, E.; Ferraro, A.; Frolov, V.; Galeotti, P.; Garbini, M.; Gemme, G.; Gnesi, I.; Grazzi, S.; Gustavino, C.; Hatzifotiadou, D.; Liciulli, F.; Maggiora, A.; Maragoto Rodriguez, O.; Maron, G.; Martelli, B.; Mazziotta, M. N.; Miozzi, S.; Nania, R.; Noferini, F.; Nozzoli, F.; Panareo, M.; Panetta, M.; Paoletti, R.; Park, W.; Perasso, L.; Pilo, F.; Piragino, G.; Riggi, F.; Righini, G. C.; Rizzi, M.; Sartorelli, G.; Scapparone, E.; Schioppa, M.; Scribano, A.; Selvi, M.; Serci, S.; Siddi, E.; Squarcia, S.; Stori, L.; Taiuti, M.; Terreni, G.; Visnyei, O. B.; Vistoli, M. C.; Votano, L.; Williams, M. C. S.; Zani, S.; Zichichi, A.; Zuyeuski, R.

    2016-12-01

    The Extreme Energy Events (EEE) Project is meant to be the most extensive experiment to detect secondary cosmic particles in Italy. To this aim, more than 50 telescopes have been built at CERN and installed in high schools distributed all over the Italian territory. Each EEE telescope comprises three large area Multigap Resistive Plate Chambers (MRPCs) and is capable of reconstructing the trajectories of the charged particles traversing it with a good angular resolution. The excellent performance of the EEE telescopes allows a large variety of studies, from measuring the local muon flux in a single telescope, to detecting extensive air showers producing time correlations in the same metropolitan area, to searching for large-scale correlations between showers detected in telescopes tens, hundreds or thousands of kilometers apart. In addition to its scientific goal, the EEE Project also has an educational and outreach objective, its aim being to motivate young people by involving them directly in a real experiment. High school students and teachers are involved in the construction, testing and start-up of the EEE telescope in their school, then in its maintenance and data-acquisition, and later in the analysis of the data. During the last couple of years a great boost has been given to the EEE Project through the organization of simultaneous and centralized data taking with the whole telescope array. The raw data from all telescopes are transferred to CNAF (Bologna), where they are reconstructed and stored. The data are currently being analyzed, looking at various topics: variation of the rate of cosmic muons with time, upward going muons, muon lifetime, search for anisotropies in the muon angular distribution and for time coincidences between stations. In this paper an overall description of the experiment is given, including the design, construction and performance of the telescopes. The operation of the whole array is also presented by showing the most recent

  7. Possible spin frustration in Nd2Ti2O7 probed by muon spin relaxation.

    PubMed

    Guo, Hanjie; Xing, Hui; Tong, Jun; Tao, Qian; Watanabe, Isao; Xu, Zhu-an

    2014-10-29

    Muon spin relaxation on Nd2Ti2O7 (NTO) and NdLaTi2O7 (NLTO) compounds are presented. The time spectra for both compounds are as expected for the paramagnetic state at high temperatures, but deviate from the exponential function below around 100 K. Firstly, the muon spin relaxation rate increases with decreasing temperature and then levels off below around 10 K, which is reminiscent of the frustrated systems. An enhancement of the relaxation rate by a longitudinal field in the paramagnetic state is observed for NTO and eliminated by a magnetic dilution for the NLTO sample. This suggests that the spectral density is modified by a magnetic dilution and thus indicates that the spins behave cooperatively rather than individually. The zero-field measurement at 0.3 K indicates that the magnetic ground state for NTO is ferromagnetic.

  8. Upgrade of the ATLAS muon spectrometer for operation at the HL-LHC

    NASA Astrophysics Data System (ADS)

    Kortner, Oliver

    2017-02-01

    The High-Luminosity Large Hadron Collider will increase the sensitivity of the ATLAS experiment to rare physics processes. In order to cope with a 10 times higher instantaneous luminosity compared to the LHC, the trigger system of ATLAS needs to be upgraded. The ATLAS experiment plans to increase the maximum rate capability of the 1st trigger level to 1 MHz at 6 μ s latency. This requires new on- and off-chamber electronics for its muon spectrometer. The replacement of the precision chamber read-out electronics will make it possible to include their data in the 1st level trigger decision and thus to increase the selectivity of the 1st level muon trigger. The acceptance of the present RPC trigger system in the barrel region will be increased from 75% to 95% by the installation of additional thin-gap RPC with a substantially increased high-rate capability compared to the current RPCs.

  9. FLUKA Monte Carlo assessment of the terrestrial muon flux at low energies and comparison against experimental measurements

    NASA Astrophysics Data System (ADS)

    Infantino, Angelo; Blackmore, Ewart W.; Brugger, Markus; Alía, Rubén García; Stukel, Matthew; Trinczek, Michael

    2016-12-01

    In recent years, there has been an increasing interest in the assessment and modelling of Galactic Cosmic Rays (GCR) particularly regarding the evaluation of the radiation effects on airline crew and passengers, interplanetary missions and on-board microelectronics. In the latter field, today the problem is not just limited to Single Event Effects (SEE) as used in avionics, but is more and more observed at ground level. Galactic cosmic muons, coming from the interaction of primary cosmic rays in the Earth's atmosphere, represent the most numerous species at ground level. In this work, we used the Monte Carlo code FLUKA to assess the atmospheric and terrestrial neutron and muon differential fluxes at various altitudes and specific examples such as the geographic coordinates corresponding to New York City and Vancouver. In this context, particle energy spectra were compared with references available in literature, calculation results obtained by both the QARM and EXPACS codes, as well as recently performed measurements. In addition, the zenith angular distribution, at ground level, was assessed for both neutrons and muons and compared with available references. Differential particle fluxes assessed for Vancouver were used as a primary source to simulate a muon detector currently taking data at TRIUMF to evaluate the passing and stopping terrestrial muon rate under different conditions. Finally, simulations were compared with the experimental measurements made at TRIUMF. Results show an excellent agreement between the FLUKA simulations and both references and the experimental measurements made at TRIUMF.

  10. Video Screen Capture Basics

    ERIC Educational Resources Information Center

    Dunbar, Laura

    2014-01-01

    This article is an introduction to video screen capture. Basic information of two software programs, QuickTime for Mac and BlueBerry Flashback Express for PC, are also discussed. Practical applications for video screen capture are given.

  11. Muon to electron conversion: how to find an electron in a muon haystack

    SciTech Connect

    Kurup, A.

    2010-07-05

    The standard model (SM) of particle physics describes how the Universe works at a fundamental level. Even though this theory has proven to be very successful over the past 50 years, we know it is incomplete. Many theories that go beyond the SM predict the occurrence of certain processes that are forbidden by the SM, such as muon to electron conversion. This paper will briefly review the history of muon to electron conversion and focus on the high-precision experiments currently being proposed, COMET (Coherent Muon to Electron Transition) and Mu2e, and a next-generation experiment, PRISM. The PRISM experiment intends to use a novel type of accelerator called a fixed-field alternating-gradient (FFAG) accelerator. There has recently been renewed interest in FFAGs for the Neutrino Factory and the Muon Collider, and because they have applications in many areas outside of particle physics, such as energy production and cancer therapy. The synergies between these particle physics experiments and other applications will also be discussed.

  12. The Muon Portal Project: Design and construction of a scanning portal based on muon tomography

    NASA Astrophysics Data System (ADS)

    Antonuccio, V.; Bandieramonte, M.; Becciani, U.; Bonanno, D. L.; Bonanno, G.; Bongiovanni, D.; Fallica, P. G.; Garozzo, S.; Grillo, A.; La Rocca, P.; Leonora, E.; Longhitano, F.; Lo Presti, D.; Marano, D.; Parasole, O.; Pugliatti, C.; Randazzo, N.; Riggi, F.; Riggi, S.; Romeo, G.; Romeo, M.; Russo, G. V.; Santagati, G.; Timpanaro, M. C.; Valvo, G.

    2017-02-01

    Cosmic ray tomography is a technique which exploits the multiple Coulomb scattering of highly penetrating cosmic ray-produced muons to perform non-destructive inspection of high-Z materials without the use of artificial radiation. A muon tomography detection system can be used as a portal monitor at border crossing points for detecting illegal targeted objects. The Muon Portal Project is a joint initiative between Italian research and industrial partners, aimed at the construction of a real size detector prototype (6×3×7 m3) for the inspection of cargo containers by the muon scattering technique. The detector consists of four XY tracking planes, two placed above and two below the container to be inspected. After a research and development phase, which led to the choice and test of the individual components, the construction and installation of the detection modules is almost completed. In this paper the present status of the Project is reported, focusing on the design and construction phase, as well as on the preliminary results obtained with the first detection planes.

  13. Muon to electron conversion: how to find an electron in a muon haystack.

    PubMed

    Kurup, A

    2010-08-13

    The standard model (SM) of particle physics describes how the Universe works at a fundamental level. Even though this theory has proven to be very successful over the past 50 years, we know it is incomplete. Many theories that go beyond the SM predict the occurrence of certain processes that are forbidden by the SM, such as muon to electron conversion. This paper will briefly review the history of muon to electron conversion and focus on the high-precision experiments currently being proposed, COMET (Coherent Muon to Electron Transition) and Mu2e, and a next-generation experiment, PRISM. The PRISM experiment intends to use a novel type of accelerator called a fixed-field alternating-gradient (FFAG) accelerator. There has recently been renewed interest in FFAGs for the Neutrino Factory and the Muon Collider, and because they have applications in many areas outside of particle physics, such as energy production and cancer therapy. The synergies between these particle physics experiments and other applications will also be discussed.

  14. Application of muon spin relaxation experiment to the mixed state superconductors

    SciTech Connect

    Inui, M. ); Harshman, D.R. )

    1991-05-09

    We discuss the use of muon spin relaxation ({mu}{sup +}SR) technique to study the mixed state of superconductors. Besides the application for static vortex configurations, we argue that large vortex motion can manifest itself as a narrowed time-averaged field distribution, which in turn results in a smaller relaxation rate. A static but disordered vortex configuration can also reduce the relaxation. We summarize these arguments. 7 refs.

  15. Muon-induced background to proton decay in the p →K+ ν decay channel with large underground liquid argon TPC detectors

    NASA Astrophysics Data System (ADS)

    Klinger, J.; Kudryavtsev, V. A.; Richardson, M.; Spooner, N. J. C.

    2015-06-01

    Large liquid argon TPC detector programs such as LBNE and LAGUNA-LBNO will be able to make measurements of the proton lifetime which will outperform Cherenkov detectors in the proton decay channel p →K+ ν. At the large depths which are proposed for such experiments, a non-negligible source of isolated charged kaons may be produced in the showers of cosmogenic muons. We present an estimate of the cosmogenic muon background to proton decay in the p →K+ ν channel. The simulation of muon transport to a depth of 4 km w.e. is performed in the MUSIC framework and the subsequent propagation of muons and secondary particles in the vicinity of a cylindrical 20 kt LAr target is performed using GEANT4. An exposure time of 100 years is considered, with a rate of <0.0012 events/kt/year at 90% CL predicted from our simulations.

  16. READOUT ELECTRONICS FOR A HIGH-RATE CSC DETECTOR

    SciTech Connect

    OCONNOR,P.; GRATCHEV,V.; KANDASAMY,A.; POLYCHRONAKOS,V.; TCHERNIATINE,V.; PARSONS,J.; SIPPACH,W.

    1999-09-25

    A readout system for a high-rate muon Cathode Strip Chamber (CSC) is described. The system, planned for use in the forward region of the ATLAS muon spectrometer, uses two custom CMOS integrated circuits to achieve good position resolution at a flux of up to 2,500 tracks/cm{sup 2}/s.

  17. Chromaticity correction for a muon collider optics

    SciTech Connect

    Alexahin, Y.; Gianfelice-Wendt, E.; Kapin, V.; /Fermilab

    2011-03-01

    Muon Collider (MC) is a promising candidate for the next energy frontier machine. However, in order to obtain peak luminosity in the 10{sup 34} cm{sup 2}s{sup -1} range the collider lattice designmust satisfy a number of stringent requirements. In particular the expected large momentum spread of the muon beam and the very small {beta}* call for a careful correction of the chromatic effects. Here we present a particular solution for the interaction region (IR) optics whose distinctive feature is a three-sextupole local chromatic correction scheme. The scheme may be applied to other future machines where chromatic effects are expected to be large. The expected large muon energy spread requires the optics to be stable over a wide range of momenta whereas the required luminosity calls for {beta}* in the mm range. To avoid luminosity degradation due to hour-glass effect, the bunch length must be comparatively small. To keep the needed RF voltage within feasible limits the momentum compaction factor must be small over the wide range of momenta. A low {beta}* means high sensitivity to alignment and field errors of the Interaction Region (IR) quadrupoles and large chromatic effects which limit the momentum range of optics stability and require strong correction sextupoles, which eventually limit the Dynamic Aperture (DA). Finally, the ring circumference should be as small as possible, luminosity being inversely proportional to the collider length. A promising solution for a 1.5 TeV center of mass energy MC with {beta}* = 1 m in both planes has been proposed. This {beta}* value has been chosen as a compromise between luminosity and feasibility based on the magnet design and energy deposition considerations. The proposed solution for the IR optics together with a new flexible momentum compaction arc cell design allows to satisfy all requirements and is relatively insensitive to the beam-beam effect.

  18. Densitometric tomography using the measurement of muon flux

    NASA Astrophysics Data System (ADS)

    Hivert, F.; Busto, J.; Brunner, J.; Salin, P.; Gaffet, S.

    2013-12-01

    The knowledge of the subsurface properties is essentially obtained by geophysical methods, e.g. seismic imaging, electric prospection or gravimetry. The present work develops a recent method to investigate the in situ density of rocks using atmospheric the muon flux measurement , its attenuation depending on the rock density and thickness. This new geophysical technique have been mainly applied in volcanology (Lesparre N., 2011) using scintillator detectors. The present project (T2DM2) aims to realize underground muons flux measurements in order to characterizing the rock massif density variations above the LSBB underground research facility in Rustrel (France). The muon flux will be measure with a new Muon telescope instrumentation using Micromegas detectors in Time Projection Chambers (TPC) configuration. The first step of the work presented considers the muon flux simulation using the Gaisser model, for the interactions between muons and atmospheric particles, and the MUSIC code (Kudryavtsev V. A., 2008) for the muons/rock interactions. The results show that the muon flux attenuation caused by density variations are enough significant to be observed until around 500 m depth and for period of time in the order of one month. Such a duration scale and depth of investigation is compatible with the duration of the water transfer processes involved within the Karst unsaturated zone where LSBB is located. Our work now concentrates on the optimization of the spatial distribution of detectors that will be deployed in future.

  19. Alignment of the Muon System at the CMS Experiment

    NASA Astrophysics Data System (ADS)

    Mueller, Ryan; Perniè, Luca; Pakhotin, Yuriy; Kamon, Teruki; Safonov, Alexei; Brown, Malachi

    2017-01-01

    The muon detectors of the CMS experiment provide fast trigger decisions, muon identifications and muon track measurements. Alignment of the muon detectors is crucial for accurate reconstruction of events with high pT muons that are present in signatures for many new physics scenarios. The muon detector's relative positions and orientations with respect to the inner silicon tracker may be precisely measured using reconstructed tracks propagating from the interaction point. This track-based alignment procedure is capable of aligning individual muon detectors to within 100 microns along sensitive modes. However, weak (insensitive) modes may not be well measured due to the system's design and cause systematic miss-measurements. In this report, we present a new track-based procedure which enables all 6 alignment parameters - 3 positions and 3 rotations for each individual muon detector. The improved algorithm allows for measurement of weak modes and considerably reduced related systematic uncertainties. We describe results of the alignment procedure obtained with 2016 data.

  20. Participation in Muon Collider/Neutrino Factory Research and Development

    SciTech Connect

    Torun, Yagmur

    2013-03-20

    Muon accelerators hold great promise for the future of high energy physics and their construction can be staged to support a broad physics program. Great progress was made over the past decade toward developing the technology for muon beam cooling which is one of the main challenges for building such facilities.

  1. Muon tomography of rock density using Micromegas-TPC telescope

    NASA Astrophysics Data System (ADS)

    Hivert, Fanny; Busto, José; Gaffet, Stéphane; Ernenwein, Jean-Pierre; Brunner, Jurgen; Salin, Pierre; Decitre, Jean-Baptiste; Lázaro Roche, Ignacio; Martin, Xavier

    2014-05-01

    The knowledge of the subsurface properties is essentially obtained by geophysical methods, e.g., seismic imaging, electric prospection or gravimetry. The current work is based on a recently developed method to investigate in situ the density of rocks using a measurement of the muon flux, whose attenuation depends on the quantity of matter the particles travel through and hence on the rock density and thickness. The present project (T2DM2) aims at performing underground muon flux measurements in order to characterize spatial and temporal rock massif density variations above the LSBB underground research facility in Rustrel (France). The muon flux will be measured with a new muon telescope device using Micromegas-Time Projection Chamber (TPC) detectors. The first step of the work presented covers the muon flux simulation based on the Gaisser model (Gaisser T., 1990), for the muon flux at the ground level, and on the MUSIC code (Kudryavtsev V. A., 2008) for the propagation of muons through the rock. The results show that the muon flux distortion caused by density variations is enough significant to be observed at 500 m depth for measurement times of about one month. This time-scale is compatible with the duration of the water transfer processes within the unsaturated Karst zone where LSBB is located. The work now focuses on the optimization of the detector layout along the LSBB galleries in order to achieve the best sensitivity.

  2. Muon-induced spallation backgrounds in DUNE

    NASA Astrophysics Data System (ADS)

    Zhu, Guanying; Li, Shirley; Beacom, John

    2017-01-01

    Galactic supernovae are rare, just a few per century, so it is important to be prepared. If we are, then the long-baseline detector DUNE could detect thousands of events, compared to the tens from SN 1987A. An important question is backgrounds from muon-induced spallation reactions. We simulate particle energy-loss processes in liquid argon, and compare relevant isotope yields with those in the water-Cherenkov detector SuperK. Our approach will help optimize the design of DUNE and further benefit the study of supernova neutrinos. GZ, SWL, and JFB are supported by NSF Grant PHY-1404311.

  3. Atmospheric effects on the underground muon intensity

    NASA Technical Reports Server (NTRS)

    Fenton, A. G.; Fenton, K. B.; Humble, J. E.; Hyland, G. B.

    1985-01-01

    It has previously been reported that the barometric pressure coefficient observed for muons at Poatina (vertical absorber depth 357 hg/sq cm) appears to be appreciably higher than would be expected from atmospheric absorption alone. There is a possibility that the effect is due to an upper atmospheric temperature effect arising from an inverse correlation of surface pressure with stratospheric temperature. A new proportional telescope is discussed which has been operating at Poatina since about the beginning of 83 and which has a long term stability suitable for studying variations of atmospheric origin.

  4. The Muon g-2 experiment at Fermilab

    NASA Astrophysics Data System (ADS)

    Chapelain, Antoine

    2017-03-01

    The upcoming Fermilab E989 experiment will measure the muon anomalous magnetic moment aμ. This measurement is motivated by the previous measurement performed in 2001 by the BNL E821 experiment that reported a 3-4 standard deviation discrepancy between the measured value and the Standard Model prediction. The new measurement at Fermilab aims to improve the precision by a factor of four reducing the total uncertainty from 540 parts per billion (BNL E821) to 140 parts per billion (Fermilab E989). This paper gives the status of the experiment.

  5. (Studies of high energy phenomena using muons)

    SciTech Connect

    Not Available

    1991-01-01

    This report covers the activities of the NIU high energy physics group as supported by DOE contract FG02-91ER40641 during the period from March 1991 to December 1991. Our group has three main efforts. The first is the D0 experiment at the Fermilab proton-antiproton collider, with major emphasis on its muon system. The second is the involvement of a portion of the group in Fermilab Experiment 789. Finally, we are also members of the SDC collaboration at the SSC.

  6. Stochastic processes in muon ionization cooling

    NASA Astrophysics Data System (ADS)

    Errede, D.; Makino, K.; Berz, M.; Johnstone, C. J.; Van Ginneken, A.

    2004-02-01

    A muon ionization cooling channel consists of three major components: the magnet optics, an acceleration cavity, and an energy absorber. The absorber of liquid hydrogen contained by thin aluminum windows is the only component which introduces stochastic processes into the otherwise deterministic acceleration system. The scattering dynamics of the transverse coordinates is described by Gaussian distributions. The asymmetric energy loss function is represented by the Vavilov distribution characterized by the minimum number of collisions necessary for a particle undergoing loss of the energy distribution average resulting from the Bethe-Bloch formula. Examples of the interplay between stochastic processes and deterministic beam dynamics are given.

  7. Leptomeson contribution to the muon g -2

    NASA Astrophysics Data System (ADS)

    Zhuridov, Dmitry

    2016-02-01

    Many models on the market allow for particles carrying both lepton number and color, e.g., leptoquarks and leptogluons. Some of the models with this feature can also accommodate color-singlet leptohadrons. We have found that the long-standing discrepancy between the experimental result and the Standard Model prediction for the muon anomalous magnetic moment can be explained by the effect of leptomesons with masses of a few hundred GeV and couplings to the leptons and mesons either of O (1 0-2) (vector-meson case) or of O (1 ) (scalar case). These new particles are testable at the current run of the LHC.

  8. Can galileons solve the muon problem?

    NASA Astrophysics Data System (ADS)

    Lamm, Henry

    2015-09-01

    The leptonic bound states positronium and muonium are used to constrain Galileon contributions to the Lamb shift of muonic hydrogen. Through the application of a variety of bounds on lepton compositeness, it is shown that either the assumption of equating the charge radius of a particle with its Galileon scale radius is incompatible with experiments, or the scale of Galileons must be M >1.33 GeV , too large to solve the muon problem. The possibility of stronger constraints in the future from true muonium is discussed.

  9. EDOS Data Capture for ALOS

    NASA Technical Reports Server (NTRS)

    McLemore, Bruce; Cordier, Guy R.; Wood, Terri; Gamst, Harek

    2012-01-01

    In 2008, NASA's Earth Sciences Missions Operations (ESMO) at Goddard Space Flight Center (GSFC) directed the Earth Observing System Data Operations System (EDOS) project to provide a prototype system to assess the feasibility of high rate data capture for the Japan Aerospace Exploration Agency's (JAXA) Advanced Land Observing Satellite (ALOS) spacecraft via NASA's Tracking and Data Relay Satellite System (TDRSS). The key objective of this collaborative effort between NASA and JAXA was to share science data collected over North and South America previously unavailable due to limitations in ALOS downlink capacity. EDOS provided a single system proof-of-concept in 4 months at White Sands TDRS Ground Terminal The system captured 6 ALOS events error-free at 277 Mbps and delivered the data to the Alaska Satellite Facility (ASF) within 3 hours (May/June '08). This paper describes the successful rapid prototyping approach which led to a successful demonstration and agreement between NASA and JAXA for operational support. The design of the operational system will be discussed with emphasis on concurrent high-rate data capture, Level-O processing, real-time display and high-rate delivery with stringent latency requirements. A similar solution was successfully deployed at Svalbard, Norway to support the Suomi NPP launch (October 2011) and capture all X-band data and provide a 30-day backup archive.

  10. Cosmic rays muon flux measurements at Belgrade shallow underground laboratory

    SciTech Connect

    Veselinović, N. Dragić, A. Maletić, D. Joković, D. Savić, M. Banjanac, R. Udovičić, V. Aničin, I.

    2015-02-24

    The Belgrade underground laboratory is a shallow underground one, at 25 meters of water equivalent. It is dedicated to low-background spectroscopy and cosmic rays measurement. Its uniqueness is that it is composed of two parts, one above ground, the other bellow with identical sets of detectors and analyzing electronics thus creating opportunity to monitor simultaneously muon flux and ambient radiation. We investigate the possibility of utilizing measurements at the shallow depth for the study of muons, processes to which these muons are sensitive and processes induced by cosmic rays muons. For this purpose a series of simulations of muon generation and propagation is done, based on the CORSIKA air shower simulation package and GEANT4. Results show good agreement with other laboratories and cosmic rays stations.

  11. Bayesian image reconstruction for improving detection performance of muon tomography.

    PubMed

    Wang, Guobao; Schultz, Larry J; Qi, Jinyi

    2009-05-01

    Muon tomography is a novel technology that is being developed for detecting high-Z materials in vehicles or cargo containers. Maximum likelihood methods have been developed for reconstructing the scattering density image from muon measurements. However, the instability of maximum likelihood estimation often results in noisy images and low detectability of high-Z targets. In this paper, we propose using regularization to improve the image quality of muon tomography. We formulate the muon reconstruction problem in a Bayesian framework by introducing a prior distribution on scattering density images. An iterative shrinkage algorithm is derived to maximize the log posterior distribution. At each iteration, the algorithm obtains the maximum a posteriori update by shrinking an unregularized maximum likelihood update. Inverse quadratic shrinkage functions are derived for generalized Laplacian priors and inverse cubic shrinkage functions are derived for generalized Gaussian priors. Receiver operating characteristic studies using simulated data demonstrate that the Bayesian reconstruction can greatly improve the detection performance of muon tomography.

  12. Noise reduction in muon tomography for detecting high density objects

    NASA Astrophysics Data System (ADS)

    Benettoni, M.; Bettella, G.; Bonomi, G.; Calvagno, G.; Calvini, P.; Checchia, P.; Cortelazzo, G.; Cossutta, L.; Donzella, A.; Furlan, M.; Gonella, F.; Pegoraro, M.; Rigoni Garola, A.; Ronchese, P.; Squarcia, S.; Subieta, M.; Vanini, S.; Viesti, G.; Zanuttigh, P.; Zenoni, A.; Zumerle, G.

    2013-12-01

    The muon tomography technique, based on multiple Coulomb scattering of cosmic ray muons, has been proposed as a tool to detect the presence of high density objects inside closed volumes. In this paper a new and innovative method is presented to handle the density fluctuations (noise) of reconstructed images, a well known problem of this technique. The effectiveness of our method is evaluated using experimental data obtained with a muon tomography prototype located at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di Fisica Nucleare (INFN). The results reported in this paper, obtained with real cosmic ray data, show that with appropriate image filtering and muon momentum classification, the muon tomography technique can detect high density materials, such as lead, albeit surrounded by light or medium density material, in short times. A comparison with algorithms published in literature is also presented.

  13. Capture Their Attention: Capturing Lessons Using Screen Capture Software

    ERIC Educational Resources Information Center

    Drumheller, Kristina; Lawler, Gregg

    2011-01-01

    When students miss classes for university activities such as athletic and academic events, they inevitably miss important class material. Students can get notes from their peers or visit professors to find out what they missed, but when students miss new and challenging material these steps are sometimes not enough. Screen capture and recording…

  14. Cryogenic Carbon Capture

    SciTech Connect

    2010-07-15

    IMPACCT Project: SES is developing a process to capture CO2 from the exhaust gas of coal-fired power plants by desublimation - the conversion of a gas to a solid. Capturing CO2 as a solid and delivering it as a liquid avoids the large energy cost of CO2 gas compression. SES’ capture technology facilitates the prudent use of available energy resources. Coal is our most abundant energy resource and is an excellent fuel for baseline power production. SES capture technology can capture 99% of the CO2 emissions in addition to a wide range of other pollutants more efficiently and at lower costs than existing capture technologies. SES’ capture technology can be readily added to our existing energy infrastructure.

  15. Frontiers of muon spectroscopy—25 years of muon science at ISIS

    NASA Astrophysics Data System (ADS)

    Cottrell, Stephen

    2013-12-01

    The ISIS muon source developed with support from the European Community (EC) and groups at Grenoble, Parma, Uppsala and Munich in the late 1980s, with a single instrument providing many scientists with their first opportunity to explore the unique capabilities of muon spectroscopy. The timing was opportune, as the muon technique was making an important contribution to the study of the then recently discovered cuprate high T c superconductors. The ISIS user community developed rapidly over subsequent years, with the technique finding a broad range of applications in condensed matter physics, materials science and chemistry. The single instrument was hugely oversubscribed, and the importance of the technique was recognized in 1993 with a further grant from the EC to develop the triple beamline facility that is currently available at ISIS. During 2009 the suite of spectrometers available at the facility received a major upgrade, with the Science and Technology Facilities Council funding the development of a 5 T high field instrument that has enabled entirely new applications of muon spectroscopy to be explored. The facility continues to flourish, with a strong user community exploiting the technique to support research across an increasingly broad range of subject areas. Condensed matter science continues to be a major area of interest, with applications including semiconductors and dielectrics, superconductors, magnetism, interstitial diffusion and charge transport. Recently, however, molecular science and radical chemistry have become prominent in the ISIS programme, applications where the availability of high magnetic fields is frequently vital to the success of the experiments. For ISIS, 23 March 2012 marked a significant milestone, it being 25 years since muons were first produced at the facility for research in condensed matter and molecular science. To celebrate, the ISIS muon group organized a science symposium with the theme 'Frontiers of Muon Spectroscopy

  16. Buried plastic scintillator muon telescope (BATATA)

    NASA Astrophysics Data System (ADS)

    Alfaro, R.; de Donato, C.; D'Olivo, J. C.; Guzmán, A.; Medina-Tanco, G.; Moreno Barbosa, E.; Paic, G.; Patiño Salazar, E.; Salazar Ibarguen, H.; Sánchez, F. A.; Supanitsky, A. D.; Valdés-Galicia, J. F.; Vargas Treviño, A. D.; Vergara Limón, S.; Villaseñor, L. M.; Auger Collaboration

    2010-05-01

    Muon telescopes have multiple applications in the area of cosmic ray research. We are currently building such a detector with the objective of comparing the ground penetration of muon vs. electron-gamma signals originated in cosmic ray showers. The detector is composed by a set of three parallel dual-layer scintillator planes, buried at fixed depths ranging from 120 to 600g/cm2. Each layer is 4m2 and is composed by 49 rectangular strips of 4cm×2m, oriented at a 90∘ angle with respect to its companion layer, which gives an xy-coincidence pixel of 4×4cm2. The scintillators are MINOS extruded polystyrene strips, with an embedded Bicron BC92 wavelength shifting (WLS) fibers, of 1.5 mm in diameter. Light is collected by Hamamatsu H7546B multi-anode PMTs of 64 pixels. The front-end (FE) electronics works in counting mode and signals are transmitted to the surface DAQ stage using low-voltage differential signaling (LVDS). Any strip signal above threshold opens a GPS-tagged 2μs data collection window. Data, including signal and background, are acquired by a system of FPGA (Spartan 2E) boards and a single-board computer (TS7800).

  17. Li diffusion in LixCoO2 probed by muon-spin spectroscopy.

    PubMed

    Sugiyama, Jun; Mukai, Kazuhiko; Ikedo, Yutaka; Nozaki, Hiroshi; Månsson, Martin; Watanabe, Isao

    2009-10-02

    The diffusion coefficient of Li+ ions (D(Li)) in the battery material LixCoO2 has been investigated by muon-spin relaxation (mu+SR). Based on experiments in zero and weak longitudinal fields at temperatures up to 400 K, we determined the fluctuation rate (nu) of the fields on the muons due to their interaction with the nuclear moments. Combined with susceptibility data and electrostatic potential calculations, clear Li+ ion diffusion was detected above approximately 150 K. The D(Li) estimated from nu was in very good agreement with predictions from first-principles calculations, and we present the mu+SR technique as an optimal probe to detect D(Li) for materials containing magnetic ions.

  18. Li Diffusion in LixCoO2 Probed by Muon-Spin Spectroscopy

    NASA Astrophysics Data System (ADS)

    Sugiyama, Jun; Mukai, Kazuhiko; Ikedo, Yutaka; Nozaki, Hiroshi; Månsson, Martin; Watanabe, Isao

    2009-10-01

    The diffusion coefficient of Li+ ions (DLi) in the battery material LixCoO2 has been investigated by muon-spin relaxation (μ+SR). Based on experiments in zero and weak longitudinal fields at temperatures up to 400 K, we determined the fluctuation rate (ν) of the fields on the muons due to their interaction with the nuclear moments. Combined with susceptibility data and electrostatic potential calculations, clear Li+ ion diffusion was detected above ˜150K. The DLi estimated from ν was in very good agreement with predictions from first-principles calculations, and we present the μ+SR technique as an optimal probe to detect DLi for materials containing magnetic ions.

  19. Data Acquisition with GPUs: The DAQ for the Muon $g$-$2$ Experiment at Fermilab

    SciTech Connect

    Gohn, W.

    2016-11-15

    Graphical Processing Units (GPUs) have recently become a valuable computing tool for the acquisition of data at high rates and for a relatively low cost. The devices work by parallelizing the code into thousands of threads, each executing a simple process, such as identifying pulses from a waveform digitizer. The CUDA programming library can be used to effectively write code to parallelize such tasks on Nvidia GPUs, providing a significant upgrade in performance over CPU based acquisition systems. The muon $g$-$2$ experiment at Fermilab is heavily relying on GPUs to process its data. The data acquisition system for this experiment must have the ability to create deadtime-free records from 700 $\\mu$s muon spills at a raw data rate 18 GB per second. Data will be collected using 1296 channels of $\\mu$TCA-based 800 MSPS, 12 bit waveform digitizers and processed in a layered array of networked commodity processors with 24 GPUs working in parallel to perform a fast recording of the muon decays during the spill. The described data acquisition system is currently being constructed, and will be fully operational before the start of the experiment in 2017.

  20. Performance of the ATLAS Muon Trigger in Run I and Upgrades for Run II

    NASA Astrophysics Data System (ADS)

    Kobayashi, Dai

    2015-12-01

    The ATLAS experiment at the Large Hadron Collider (LHC) has taken data at a centre-of-mass energy between 900 GeV and 8 TeV during Run I (2009-2013). The LHC delivered an integrated luminosity of about 20 fb-1 in 2012, which required dedicated strategies to ensure the highest possible physics output while effectively reducing the event rate. The Muon High Level Trigger has successfully adapted to the changing environment from low instantaneous luminosity (1032 cm-2 s-1) in 2010 to the peak high instantaneous luminosity (1034 cm-2 s-1). The selection strategy has been optimized for the various physics analyses involving muons in the final state. We will present the excellent performance achieved during Run I. In preparation for the next data taking period (Run II) several hardware and software upgrades to the ATLAS Muon Trigger have been performed to deal with the increased trigger rate expected at higher centre-of-mass energy and increased instantaneous luminosity. We will highlight the development of novel algorithms that have been developed to maintain a highly efficient event selection while reducing the processing time by a factor of three. In addition, the two stages of the high level trigger that was deployed in Run I will be merged for Run II. We will discuss novel approaches that are being developed to further improve the trigger algorithms for Run II and beyond.

  1. A method for detection of muon induced electromagnetic showers with the ANTARES detector

    NASA Astrophysics Data System (ADS)

    Aguilar, J. A.; Al Samarai, I.; Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Assis Jesus, A. C.; Astraatmadja, T.; Aubert, J. J.; Baret, B.; Basa, S.; Bertin, V.; Biagi, S.; Bigi, A.; Bigongiari, C.; Bogazzi, C.; Bou-Cabo, M.; Bouhou, B.; Bouwhuis, M. C.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Cârloganu, C.; Carminati, G.; Carr, J.; Cecchini, S.; Charif, Z.; Charvis, P.; Chiarusi, T.; Circella, M.; Coniglione, R.; Costantini, H.; Coyle, P.; Curtil, C.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drouhin, D.; Eberl, T.; Emanuele, U.; Enzenhöfer, A.; Ernenwein, J. P.; Escoffier, S.; Fermani, P.; Ferri, M.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J. L.; Galatà, S.; Gay, P.; Giacomelli, G.; Giordano, V.; Gómez-González, J. P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartman, J.; Heijboer, A. J.; Hello, Y.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; Hsu, C. C.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.; Kavatsyuk, O.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Lefèvre, D.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martinez-Mora, J. A.; Meli, A.; Montaruli, T.; Moscoso, L.; Motz, H.; Neff, M.; Nezri, E.; Palioselitis, D.; Păvălaş, G. E.; Payet, K.; Payre, P.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Reed, C.; Richardt, C.; Richter, R.; Rivière, C.; Robert, A.; Roensch, K.; Rostovtsev, A.; Ruiz-Rivas, J.; Rujoiu, M.; Russo, G. V.; Salesa, F.; Sapienza, P.; Schöck, F.; Schuller, J. P.; Schüssler, F.; Shanidze, R.; Simeone, F.; Spies, A.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, T.; Sánchez-Losa, A.; Taiuti, M.; Tamburini, C.; Toscano, S.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wijnker, G.; Wilms, J.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zúñiga, J.

    2012-05-01

    The primary aim of ANTARES is neutrino astronomy with upward going muons created in charged current muon neutrino interactions in the detector and its surroundings. Downward going muons are background for neutrino searches. These muons are the decay products of cosmic-ray collisions in the Earth's atmosphere far above the detector. This paper presents a method to identify and count electromagnetic showers induced along atmospheric muon tracks with the ANTARES detector. The method is applied to both cosmic muon data and simulations and its applicability to the reconstruction of muon event energies is demonstrated.

  2. Production of X-rays by cosmic-ray muons in heavily shielded gamma-ray spectrometers

    NASA Astrophysics Data System (ADS)

    Bikit, I.; Mrda, D.; Anicin, I.; Veskovic, M.; Slivka, J.; Krmar, M.; Todorovic, N.; Forkapic, S.

    2009-07-01

    Cosmic-ray (CR) muons both directly and indirectly contribute to the spectra of heavily shielded High Purity Germanium (HPGe) detectors, even in deep underground laboratories. Heavy elements are frequently used as the detector components or are occasionally placed close to the detector endcap, and their characteristic X-rays induced by cosmic-ray muons contribute to the low-energy region of the HPGe detector spectra. We study the production of X-rays in tungsten, gold and lead by cosmic-ray muons on the ground level, by means of a coincidence system consisting of a plastic scintillation detector and an extended range HPGe detector placed inside a 12-cm-thick lead shield. In this typical low-background arrangement, the shield with total mass of 725 kg acts as a source of secondary particles induced by CR muons. X-rays that originate from direct interactions of muons with the target material, the yield of which may be reliably estimated by Monte Carlo simulations, are excluded by this experimental setup, and only X-rays of W, Pb and Au samples produced by all secondaries from muon interactions with the lead shield are present in the HPGe spectra. The production rate of Kα X-rays per unit mass of all the elements studied (74

  3. Crossing muons in Icecube at highest energy: a cornerstone to ν Astronomy

    NASA Astrophysics Data System (ADS)

    Fargion, D.; Oliva, P.; De Sanctis Lucentini, P. G.

    2014-11-01

    above few tens TeV may be several dozens, possibly around 54, mostly enhanced along horizontal edges, painting known sources and/or self-correlating in doublets or rarest triplet, offering a first solution of the UHE neutrino source puzzle (if steady or transient nearby source are at sight). Recent preliminary ICECUBE presentation on crossing muons are consistent with our preliminary muon rate estimate.

  4. MUSE, the goddess of muons, and her future.

    PubMed

    Kadono, Ryosuke; Miyake, Yasuhiro

    2012-02-01

    The Muon Science Establishment (MUSE) is one of the major experimental facilities, along with those for neutron, hadron and neutrino experiments, in J-PARC. It makes up a part of the Materials and Life Science Experiment Facility (MLF) that hosts a tandem neutron facility (JSNS) driven by a single proton beam. The facility consists of a superconducting solenoid (for pion confinement) with a modest-acceptance (about 45 mSr) injector of pions and muons obtained from a 20 mm thick edge-cooled stationary graphite target, delivering a 'surface muon' beam (μ(+)) and a 'decay muon' beam (μ(+)/μ(-)) for a wide variety of applications. It has recently been confirmed that the beamline has the world's highest muon intensity (∼10(6) μ(+)/s) at a proton beam power of 120 kW. The beamline is furnished with two experimental areas (D1 and D2) at the exit branches, where an apparatus for muon spin rotation/relaxation experiments (μSR) is currently installed at the D1 area while test experiments are conducted at the D2 area. In this paper, the current performance of the MUSE facility as a whole is reviewed. The facility is still in the early stage of development, including both beamlines and infrastructure for experiments, and plans for upgrading it are discussed together with perspectives for research works envisaged with unprecedented high-intensity muons.

  5. Simulated Measurements of Cooling in Muon Ionization Cooling Experiment

    SciTech Connect

    Mohayai, Tanaz; Rogers, Chris; Snopok, Pavel

    2016-06-01

    Cooled muon beams set the basis for the exploration of physics of flavour at a Neutrino Factory and for multi-TeV collisions at a Muon Collider. The international Muon Ionization Cooling Experiment (MICE) measures beam emittance before and after an ionization cooling cell and aims to demonstrate emittance reduction in muon beams. In the current MICE Step IV configuration, the MICE muon beam passes through low-Z absorber material for reducing its transverse emittance through ionization energy loss. Two scintillating fiber tracking detectors, housed in spectrometer solenoid modules upstream and downstream of the absorber are used for reconstructing position and momentum of individual muons for calculating transverse emittance reduction. However, due to existence of non-linear effects in beam optics, transverse emittance growth can be observed. Therefore, it is crucial to develop algorithms that are insensitive to this apparent emittance growth. We describe a different figure of merit for measuring muon cooling which is the direct measurement of the phase space density.

  6. Testing the Capture Magnet

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image of a model capture magnet was taken after an experiment in a Mars simulation chamber at the University of Aarhus, Denmark. It has some dust on it, but not as much as that on the Mars Exploration Rover Spirit's capture magnet. The capture and filter magnets on both Mars Exploration Rovers were delivered by the magnetic properties team at the Center for Planetary Science, Copenhagen, Denmark.

  7. Where to place the positive muon in the Periodic Table?

    PubMed

    Goli, Mohammad; Shahbazian, Shant

    2015-03-14

    In a recent study it was suggested that the positively charged muon is capable of forming its own "atoms in molecules" (AIM) in the muonic hydrogen-like molecules, composed of two electrons, a muon and one of the hydrogen's isotopes, thus deserves to be placed in the Periodic Table [Phys. Chem. Chem. Phys., 2014, 16, 6602]. In the present report, the capacity of the positively charged muon in forming its own AIM is considered in a large set of molecules replacing muons with all protons in the hydrides of the second and third rows of the Periodic Table. Accordingly, in a comparative study the wavefunctions of both sets of hydrides and their muonic congeners are first derived beyond the Born-Oppenheimer (BO) paradigm, assuming protons and muons as quantum waves instead of clamped particles. Then, the non-BO wavefunctions are used to derive the AIM structures of both hydrides and muonic congeners within the context of the multi-component quantum theory of atoms in molecules. The results of the analysis demonstrate that muons are generally capable of forming their own atomic basins and the properties of these basins are not fundamentally different from those AIM containing protons. Particularly, the bonding modes in the muonic species seem to be qualitatively similar to their congener hydrides and no new bonding model is required to describe the bonding of muons to a diverse set of neighboring atoms. All in all, the positively charged muon is similar to a proton from the structural and bonding viewpoint and deserves to be placed in the same box of hydrogen in the Periodic Table. This conclusion is in line with a large body of studies on the chemical kinetics of the muonic molecules portraying the positively charged muon as a lighter isotope of hydrogen.

  8. Spatial capture-recapture

    USGS Publications Warehouse

    Royle, J. Andrew; Chandler, Richard B.; Sollmann, Rahel; Gardner, Beth

    2013-01-01

    Spatial Capture-Recapture provides a revolutionary extension of traditional capture-recapture methods for studying animal populations using data from live trapping, camera trapping, DNA sampling, acoustic sampling, and related field methods. This book is a conceptual and methodological synthesis of spatial capture-recapture modeling. As a comprehensive how-to manual, this reference contains detailed examples of a wide range of relevant spatial capture-recapture models for inference about population size and spatial and temporal variation in demographic parameters. Practicing field biologists studying animal populations will find this book to be a useful resource, as will graduate students and professionals in ecology, conservation biology, and fisheries and wildlife management.

  9. How Actuated Particles Effectively Capture Biomolecular Targets

    PubMed Central

    2017-01-01

    Because of their high surface-to-volume ratio and adaptable surface functionalization, particles are widely used in bioanalytical methods to capture molecular targets. In this article, a comprehensive study is reported of the effectiveness of protein capture by actuated magnetic particles. Association rate constants are quantified in experiments as well as in Brownian dynamics simulations for different particle actuation configurations. The data reveal how the association rate depends on the particle velocity, particle density, and particle assembly characteristics. Interestingly, single particles appear to exhibit target depletion zones near their surface, caused by the high density of capture molecules. The depletion effects are even more limiting in cases with high particle densities. The depletion effects are overcome and protein capture rates are enhanced by applying dynamic particle actuation, resulting in an increase in the association rate constants by up to 2 orders of magnitude. PMID:28192952

  10. Measuring the Disappearance of Muon Neutrinos with the MINOS Detector

    SciTech Connect

    Radovic, Alexander

    2013-08-01

    MINOS is a long baseline neutrino oscillation experiment. It measures the flux from the predominately muon neutrino NuMI beam first 1 km from beam start and then again 735 km later using a pair of steel scintillator tracking calorimeters. The comparison of measured neutrino energy spectra at our Far Detector with the prediction based on our Near Detector measurement allows for a measurement of the parameters which define neutrino oscillations. This thesis will describe the most recent measurement of muon neutrino disappearance in the NuMI muon neutrino beam using the MINOS experiment.

  11. Novel Muon Beam Facilities for Project X at Fermilab

    SciTech Connect

    Neuffer, D.V.; Ankenbrandt, C.M.; Abrams, R.; Roberts, T.J.; Yoshikawa, C.Y.; /MUONS Inc., Batavia

    2012-05-01

    Innovative muon beam concepts for intensity-frontier experiments such as muon-to-electron conversion are described. Elaborating upon a previous single-beam idea, we have developed a design concept for a system to generate four high quality, low-energy muon beams (two of each sign) from a single beam of protons. As a first step, the production of pions by 1 and 3 GeV protons from the proposed Project X linac at Fermilab is being simulated and compared with the 8-GeV results from the previous study.

  12. Muon multiplicities measured using an underground cosmic-ray array

    NASA Astrophysics Data System (ADS)

    Kuusiniemi, P.; Enqvist, T.; Bezrukov, L.; Fynbo, H.; Inzhechik, L.; Joutsenvaara, J.; Loo, K.; Lubsandorzhiev, B.; Petkov, V.; Slupecki, M.; Trzaska, W. H.; Virkajärvi, A.

    2016-05-01

    EMMA (Experiment with Multi-Muon Array) is an underground detector array designed for cosmic-ray composition studies around the knee energy (or ~ 1 — 10 PeV). It operates at the shallow depth in the Pyhasalmi mine, Finland. The array consists of eleven independent detector stations ~ 15 m2 each. Currently seven stations are connected to the DAQ and the rest will be connected within the next few months. EMMA will determine the multiplicity, the lateral density distribution and the arrival direction of high-energy muons event by event. The preliminary estimates concerning its performance together with an example of measured muon multiplicities are presented.

  13. The Muon System of the Daya Bay Reactor Antineutrino Experiment

    SciTech Connect

    An, F. P.; Hackenburg, R. W.; Brown, R. E.; Chasman, C.; Dale, E.; Diwan, M. V.; Gill, R.; Hans, S.; Isvan, Z.; Jaffe, D. E.; Kettell, S. H.; Littenberg, L.; Pearson, C. E.; Qian, X.; Theman, H.; Viren, B.; Worcester, E.; Yeh, M.; Zhang, C.

    2014-10-05

    The Daya Bay experiment consists of functionally identical antineutrino detectors immersed in pools of ultrapure water in three well-separated underground experimental halls near two nuclear reactor complexes. These pools serve both as shields against natural, low-energy radiation, and as water Cherenkov detectors that efficiently detect cosmic muons using arrays of photomultiplier tubes. Each pool is covered by a plane of resistive plate chambers as an additional means of detecting muons. Design, construction, operation, and performance of these muon detectors are described. (auth)

  14. The muon content of gamma-ray showers

    NASA Technical Reports Server (NTRS)

    Edwards, P. G.; Protheroe, R. J.

    1985-01-01

    The result of a calculation of the expected number of muons in gamma ray initiated and cosmic ray initiated air showers using a realistic model of hadronic collisions in an effort to understand the available experimental results and to assess the feasibility of using the muon content of showers as a veto to reject cosmic ray initiated showers in ultra-high energy gamma ray astronomy are reported. The possibility of observing very-high energy gamma-ray sources by detecting narrow angle anisotropies in the high energy muon background radiation are considered.

  15. Range fluctuations of high energy muons passing through matter

    NASA Technical Reports Server (NTRS)

    Minorikawa, Y.; Mitsui, K.

    1985-01-01

    The information about energy spectrum of sea level muons at high energies beyond magnetic spectrographs can be obtained from the underground intensity measurements if the fluctuations problems are solved. The correction factor R for the range fluctuations of high energy muons were calculated by analytical method of Zatsepin, where most probable energy loss parameter are used. It is shown that by using the R at great depth together with the slope, lambda, of the vertical depth-intensity (D-I) curve in the form of exp(-t/lambda), the spectral index, gamma, in the power law energy spectrum of muons at sea level can be obtained.

  16. Efficiency Studies for the new Muon Telescope Detector at STAR

    NASA Astrophysics Data System (ADS)

    Carson, Hannah; STAR Collaboration

    2013-10-01

    The Muon Telescope Detector (MTD) is a new detector subsystem in STAR at the Relativistic Heavy Ion Collider (RHIC). The MTD will contribute to studies of the matter being created in heavy-ion collisions by allowing measurements of the J/Psi meson and the different Upsilon states over a broad transverse momentum range via the reconstruction of their di-muon decays. Simulations to estimate the efficiency of the MTD for detecting muons were performed. The results of these simulations will be presented.

  17. Toward the Computational Prediction of Muon Sites and Interaction Parameters

    NASA Astrophysics Data System (ADS)

    Bonfà, Pietro; De Renzi, Roberto

    2016-09-01

    The rapid developments of computational quantum chemistry methods and supercomputing facilities motivate the renewed interest in the analysis of the muon/electron interactions in μSR experiments with ab initio approaches. Modern simulation methods seem to be able to provide the answers to the frequently asked questions of many μSR experiments: where is the muon? Is it a passive probe? What are the interaction parameters governing the muon-sample interaction? In this review we describe some of the approaches used to provide quantitative estimations of the aforementioned quantities and we provide the reader with a short discussion on the current developments in this field.

  18. Muonic alchemy: Transmuting elements with the inclusion of negative muons

    NASA Astrophysics Data System (ADS)

    Moncada, Félix; Cruz, Daniel; Reyes, Andrés

    2012-06-01

    In this Letter we present a theoretical study of atoms in which one electron has been replaced by a negative muon. We have treated these muonic systems with the Any Particle Molecular Orbital (APMO) method. A comparison between the electronic and muonic radial distributions revealed that muons are much more localized than electrons. Therefore, the muonic cloud is screening effectively one positive charge of the nucleus. Our results have revealed that by replacing an electron in an atom by a muon there is a transmutation of the electronic properties of that atom to those of the element with atomic number Z - 1.

  19. Helical FOFO Snake for 6D Ionization Cooling of Muons

    SciTech Connect

    Alexahin, Y.

    2010-03-30

    A channel for 6D ionization cooling of muons is described which consists of periodically inclined solenoids of alternating polarity, liquid hydrogen absorbers placed inside the solenoids and RF cavities between them. An important feature of such a channel (called Helical FOFO snake) is that it can cool simultaneously muons of both signs. Theoretical considerations as well as results of simulations with G4beamline are presented which show that a 200 MHz HFOFO snake has sufficient acceptance to be used for initial 6D cooling in muon colliders and neutrino factories.

  20. The muon system of the Daya Bay Reactor antineutrino experiment

    NASA Astrophysics Data System (ADS)

    An, F. P.; Balantekin, A. B.; Band, H. R.; Beriguete, W.; Bishai, M.; Blyth, S.; Brown, R. E.; Butorov, I.; Cao, G. F.; Cao, J.; Carr, R.; Chan, Y. L.; Chang, J. F.; Chang, L.; Chang, Y.; Chasman, C.; Chen, H. S.; Chen, H. Y.; Chen, Q. Y.; Chen, S. J.; Chen, S. M.; Chen, X. C.; Chen, X. H.; Chen, Y.; Chen, Y. X.; Cheng, Y. P.; Cherwinka, J. J.; Chu, M. C.; Cummings, J. P.; Dale, E.; de Arcos, J.; Deng, Z. Y.; Ding, Y. Y.; Diwan, M. V.; Draeger, E.; Du, X. F.; Dwyer, D. A.; Edwards, W. R.; Ely, S. R.; Fu, J. Y.; Ge, L. Q.; Gill, R.; Goett, J.; Gonchar, M.; Gong, G. H.; Gong, H.; Gu, W. Q.; Guan, M. Y.; Guo, X. H.; Hackenburg, R. W.; Han, G. H.; Hans, S.; He, M.; He, Q.; Heeger, K. M.; Heng, Y. K.; Hinrichs, P.; Hor, Y. K.; Hsiung, Y. B.; Hu, B. Z.; Hu, L. J.; Hu, L. M.; Hu, T.; Hu, W.; Huang, E. C.; Huang, H. X.; Huang, H. Z.; Huang, X. T.; Huber, P.; Hussain, G.; Isvan, Z.; Jaffe, D. E.; Jaffke, P.; Jetter, S.; Ji, X. L.; Ji, X. P.; Jiang, H. J.; Jiao, J. B.; Johnson, R. A.; Kang, L.; Kebwaro, J. M.; Kettell, S. H.; Kramer, M.; Kwan, K. K.; Kwok, M. W.; Kwok, T.; Lai, W. C.; Lai, W. H.; 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, W. D.; Li, X. N.; Li, X. Q.; Li, Y. Z. B.; Liang, H.; Lin, C. J.; Lin, G. L.; Lin, P. Y.; Lin, S. K.; Link, J. M.; Littenberg, L.; Littlejohn, B. R.; Liu, D. W.; Liu, H.; Liu, J. C.; Liu, J. L.; Liu, S. S.; Liu, Y. B.; Lu, C.; Lu, H. Q.; Luk, K. B.; Ma, Q. M.; Ma, X. B.; Ma, X. Y.; Ma, Y. Q.; McDonald, K. T.; McFarlane, M. C.; McKeown, R. D.; Meng, Y.; Mitchell, I.; Mohapatra, D.; Morgan, J. E.; Nakajima, Y.; Napolitano, J.; Naumov, D.; Naumova, E.; Nemchenok, I.; Newsom, C.; Ngai, H. Y.; Ngai, W. K.; Ning, Z.; Ochoa-Ricoux, J. P.; Olshevski, A.; Patton, S.; Pec, V.; Pearson, C. E.; 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.; Tam, Y. H.; Tang, X.; Themann, H.; Tsang, K. V.; Tsang, R. H. M.; Tull, C. E.; Tung, Y. C.; Viren, B.; Virostek, S.; Vorobel, V.; Wang, C. H.; Wang, L. S.; Wang, L. Y.; Wang, L. Z.; 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.; Webber, D. M.; Wei, H. Y.; Wei, Y. D.; Wen, L. J.; Whisnant, K.; White, C. G.; Whitehead, L.; Wilhelmi, J.; 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, G. H.; Xu, J.; Xu, J. L.; Xu, J. Y.; 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, J. Y.; Yu, Z. Y.; Zang, S. L.; Zhan, L.; Zhang, C.; Zhang, F. H.; Zhang, J. W.; Zhang, K.; Zhang, Q. M.; Zhang, S. H.; Zhang, Y. H.; Zhang, Y. M.; Zhang, Y. X.; Zhang, Z. J.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, J.; Zhao, Q. W.; Zhao, Y.; Zhao, Y. B.; Zheng, L.; Zhong, W. L.; Zhou, L.; Zhou, Z. Y.; Zhuang, H. L.; Zou, J. H.

    2015-02-01

    The Daya Bay experiment consists of functionally identical antineutrino detectors immersed in pools of ultrapure water in three well-separated underground experimental halls near two nuclear reactor complexes. These pools serve both as shields against natural, low-energy radiation, and as water Cherenkov detectors that efficiently detect cosmic muons using arrays of photomultiplier tubes. Each pool is covered by a plane of resistive plate chambers as an additional means of detecting muons. Design, construction, operation, and performance of these muon detectors are described.