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Sample records for lung elastic recoil

  1. Elastic recoil detection

    NASA Astrophysics Data System (ADS)

    Bik, W. M. A.; Habraken, F. H. P. M.

    1993-07-01

    In elastic recoil detection (ERD) one determines the yield and energy of particles ejected out of the surface region of samples under MeV ion bombardment. By application of this surface and thin film analysis technique one can obtain quantitative information concerning the depth distribution of light elements in a sample to be analysed. The quantitativity and the depth resolving power are based on knowledge of the recoil cross section and the stopping power of high-energy ions in matter. This paper reviews the fundamentals of this technique and the various experimental methods for recoil identification. Furthermore, important features for material analysis, such as detection limits, depth resolution and elemental range are discussed. Some emphasis is put on the conversion of the spectral contribution of the elements to atomic concentrations in the films for several representative cases. Throughout the review numerous examples are given to illustrate the features of ERD and to demonstrate empirically the accuracy of the quantification method.

  2. Elastic recoil changes in early emphysema.

    PubMed Central

    Silvers, G W; Petty, T L; Stanford, R E

    1980-01-01

    An attempt was made to determine if emphysema and static lung recoil were related in a group of 65 excised human lungs. We studied 23 normal lungs, 24 lungs with an emphysema score of 5 or less, and 18 lungs with an emphysema score greater than 5. A comparison of the percentage of predicted elastic recoil revealed that both emphysema groups were significantly different from normal lungs. In addition, the total lung capacities were significantly different between the three groups. In the group with an emphysema score greater than 5 we found a linear negative correlation between the extent of emphysema and percent of predicted elastic recoil at 90% total lung capacity (r = -0.696, p < 0.01). We found a negative correlation between the percentage of predicted elastic recoil and the lung volume (r = -0.612, p < 0.01). We conclude that a significant loss of elastic recoil and a significant increase in total lung capacity occurs in the early stages of emphysema. PMID:7434309

  3. The recoil proton polarization in. pi. p elastic scattering

    SciTech Connect

    Seftor, C.J.

    1988-09-01

    The polarization of the recoil proton for ..pi../sup +/p and ..pi../sup -/p elastic scattering has been measured for various angles at 547 MeV/c and 625 MeV/c by a collaboration involving The George Washington University; the University of California, Los Angeles; and Abilene Christian University. The experiment was performed at the P/sup 3/ East experimental area of the Los Alamos Meson Physics Facility. Beam intensities varied from 0.4 to 1.0 x 10/sup 7/ ..pi../sup -/'s/sec and from 3.0 to 10.0 x 10/sup 7/ ..pi../sup +/'s/sec. The beam spot size at the target was 1 cm in the horizontal direction by 2.5 cm in the vertical direction. A liquid-hydrogen target was used in a flask 5.7 cm in diameter and 10 cm high. The scattered pion and recoil proton were detected in coincidence using the Large Acceptance Spectrometer (LAS) to detect and momentum analyze the pions and the JANUS recoil proton polarimeter to detect and measure the polarization of the protons. Results from this experiment are compared with previous measurements of the polarization, with analyzing power data previously taken by this group, and to partial-wave analysis predictions. 12 refs., 53 figs., 18 tabs.

  4. Influence of elastic recoil on restenosis after successful coronary angioplasty in unstable angina pectoris.

    PubMed

    Ardissino, D; Di Somma, S; Kubica, J; Barberis, P; Merlini, P A; Eleuteri, E; De Servi, S; Bramucci, E; Specchia, G; Montemartini, C

    1993-03-15

    The elastic behavior of the dilated coronary vessel has been reported to affect the immediate results of coronary angioplasty. To determine whether elastic recoil may also influence the long-term restenosis process, 98 consecutive patients with unstable angina and 1-vessel disease were studied. An automated coronary quantitative program was used for the assessment of balloon and coronary luminal diameters. Elastic recoil was defined as the percent reduction between minimal balloon diameter at the highest inflation pressure and minimal lesion diameter immediately after coronary angioplasty. Follow-up coronary arteriography was performed 8 to 12 months after the procedure in all patients. The mean elastic recoil averaged 17.7 +/- 16% and was correlated to the degree of residual stenosis immediately after coronary angioplasty (r = 0.64; p < 0.001). Restenosis, defined as > 50% diameter stenosis at follow-up, developed in 53 patients (54%). There was no correlation between the degree of elastic recoil and the changes in minimal lesion diameter observed during follow-up, whereas a positive correlation between the amount of elastic recoil and the incidence of restenosis was documented (r = 0.84; p < 0.05). Thus, the elastic properties of the dilated vessel do not influence the active process of restenosis. However, because elastic recoil negatively influences the initial results of angioplasty, it is more likely that further reductions in lumen diameter during follow-up can reach a threshold of obstruction considered critical for a binary definition of restenosis. PMID:8447261

  5. Elastic recoil of coronary stents: a comparative analysis.

    PubMed

    Barragan, P; Rieu, R; Garitey, V; Roquebert, P O; Sainsous, J; Silvestri, M; Bayet, G

    2000-05-01

    Minimum elastic recoil (ER) has became an essential feature of new coronary stents when deployed in artheromatous lesions of various morphologies. The ER of coronary stent might be an important component of 6-month restenosis rate by minimizing the luminal loss. We evaluated the intrinsic ER of 23 coronary stents with a mechanical test bench. The amount of ER for one size of stent (3.0 mm) was quantified using a 3D optical contactless machine (Smartscope MVP, Rochester, NY). The stents were expanded on their own balloon for the precrimped stents; the uncrimped stents were expended using identical 3.0-mm balloons. Two types of measurements were done without exterior stress and with a 0.2-bar exterior stress, directly on the stent at the end of balloon expansion, immediately after balloon deflation, and then 30 min, 60 min, and 120 min after. ER ranged from 1.54%+/-0.81% (Bestent BES 15) to 16.51%+/-2.89% (Paragon stent) without stress (P<0.01) and from 2.35%+/-1.14% (Bestent BES 15) to 18.34%+/-2.41% (Cook GR2) under 0.2-bar pressure (P<0.0001). Furthermore, there was a significant reduction between the mean result of tubular stents (TS) and coil stents (CS). The results of in vitro mechanical tests may confirm strongly the interest of a minimum ER in the prevention of the 6-month restenosis. PMID:10816295

  6. Damped elastic recoil of the titin spring in myofibrils of human myocardium

    PubMed Central

    Opitz, Christiane A.; Kulke, Michael; Leake, Mark C.; Neagoe, Ciprian; Hinssen, Horst; Hajjar, Roger J.; Linke, Wolfgang A.

    2003-01-01

    The giant protein titin functions as a molecular spring in muscle and is responsible for most of the passive tension of myocardium. Because the titin spring is extended during diastolic stretch, it will recoil elastically during systole and potentially may influence the overall shortening behavior of cardiac muscle. Here, titin elastic recoil was quantified in single human heart myofibrils by using a high-speed charge-coupled device-line camera and a nanonewtonrange force sensor. Application of a slack-test protocol revealed that the passive shortening velocity (Vp) of nonactivated cardiomyofibrils depends on: (i) initial sarcomere length, (ii) release-step amplitude, and (iii) temperature. Selective digestion of titin, with low doses of trypsin, decelerated myofibrillar passive recoil and eventually stopped it. Selective extraction of actin filaments with a Ca2+-independent gelsolin fragment greatly reduced the dependency of Vp on release-step size and temperature. These results are explained by the presence of viscous forces opposing myofibrillar passive recoil that are caused mainly by weak actin–titin interactions. Thus, Vp is determined by two distinct factors: titin elastic recoil and internal viscous drag forces. The recoil could be modeled as that of a damped entropic spring consisting of independent worm-like chains. The functional importance of myofibrillar elastic recoil was addressed by comparing instantaneous Vp to unloaded shortening velocity, which was measured in demembranated, fully Ca2+-activated, human cardiac fibers. Titin-driven passive recoil was much faster than active unloaded shortening velocity in early phases of isotonic contraction. Damped myofibrillar elastic recoil could help accelerate active contraction speed of human myocardium during early systolic shortening. PMID:14563922

  7. Mass calibration of the energy axis in ToF-E elastic recoil detection analysis

    NASA Astrophysics Data System (ADS)

    Meersschaut, J.; Laricchiuta, G.; Sajavaara, T.; Vandervorst, W.

    2016-03-01

    We report on procedures that we have developed to mass-calibrate the energy axis of ToF-E histograms in elastic recoil detection analysis. The obtained calibration parameters allow one to transform the ToF-E histogram into a calibrated ToF-M histogram.

  8. A recoil detector for the measurement of antiproton-proton elastic scattering at angles close to 90°

    NASA Astrophysics Data System (ADS)

    Hu, Q.; Bechstedt, U.; Gillitzer, A.; Grzonka, D.; Khoukaz, A.; Klehr, F.; Lehrach, A.; Prasuhn, D.; Ritman, J.; Sefzick, T.; Stockmanns, T.; Täschner, A.; Wuestner, P.; Xu, H.

    2014-10-01

    The design and construction of a recoil detector for the measurement of recoil protons of antiproton-proton elastic scattering at scattering angles close to are described. The performance of the recoil detector has been tested in the laboratory with radioactive sources and at COSY with proton beams by measuring proton-proton elastic scattering. The results of laboratory tests and commissioning with beam are presented. Excellent energy resolution and proper working performance of the recoil detector validate the conceptual design of the KOALA experiment at HESR to provide the cross section data needed to achieve a precise luminosity determination at the PANDA experiment.

  9. A predictive theory for elastic scattering and recoil of protons from 4He

    DOE PAGESBeta

    Hupin, Guillaume; Quaglioni, Sofia; Navratil, Petr

    2014-12-08

    Low-energy cross sections for elastic scattering and recoil of protons from 4He nuclei (also known as α particles) are calculated directly by solving the Schrodinger equation for five nucleons interacting through accurate two- and three-nucleon forces derived within the framework of chiral effective field theory. Precise knowledge of these processes at various proton backscattering/recoil angles and energies is needed for the ion-beam analysis of numerous materials, from the surface layers of solids, to thin films, to fusion-reactor materials. Indeed, the same elastic scattering process, in two different kinematic configurations, can be used to probe the concentrations and depth profiles ofmore » either hydrogen or helium. Furthermore, we compare our results to available experimental data and show that direct calculations with modern nuclear potentials can help to resolve remaining inconsistencies among data sets and can be used to predict these cross sections when measurements are not available.« less

  10. Predictive theory for elastic scattering and recoil of protons from 4He

    NASA Astrophysics Data System (ADS)

    Hupin, Guillaume; Quaglioni, Sofia; Navrátil, Petr

    2014-12-01

    Low-energy cross sections for elastic scattering and recoil of protons from 4He nuclei (also known as α particles) are calculated directly by solving the Schrödinger equation for five nucleons interacting through accurate two- and three-nucleon forces derived within the framework of chiral effective field theory. Precise knowledge of these processes at various proton backscattering/recoil angles and energies is needed for the ion-beam analysis of numerous materials, from the surface layers of solids, to thin films, to fusion-reactor materials. Indeed, the same elastic scattering process, in two different kinematic configurations, can be used to probe the concentrations and depth profiles of either hydrogen or helium. We compare our results to available experimental data and show that direct calculations with modern nuclear potentials can help to resolve remaining inconsistencies among data sets and can be used to predict these cross sections when measurements are not available.

  11. A predictive theory for elastic scattering and recoil of protons from 4He

    SciTech Connect

    Hupin, Guillaume; Quaglioni, Sofia; Navratil, Petr

    2014-12-08

    Low-energy cross sections for elastic scattering and recoil of protons from 4He nuclei (also known as α particles) are calculated directly by solving the Schrodinger equation for five nucleons interacting through accurate two- and three-nucleon forces derived within the framework of chiral effective field theory. Precise knowledge of these processes at various proton backscattering/recoil angles and energies is needed for the ion-beam analysis of numerous materials, from the surface layers of solids, to thin films, to fusion-reactor materials. Indeed, the same elastic scattering process, in two different kinematic configurations, can be used to probe the concentrations and depth profiles of either hydrogen or helium. Furthermore, we compare our results to available experimental data and show that direct calculations with modern nuclear potentials can help to resolve remaining inconsistencies among data sets and can be used to predict these cross sections when measurements are not available.

  12. Elastic recoil detection analysis of hydrogen with 7Li ions using a polyimide foil as a thick hydrogen reference

    NASA Astrophysics Data System (ADS)

    Pelicon, Primož; Razpet, Alenka; Markelj, Sabina; Čadež, Iztok; Budnar, Miloš

    2005-01-01

    Elastic recoil detection analysis (ERDA) with an absorber foil using a 4.2 MeV 7Li2+ beam was utilized for evaluation of hydrogen depth profiles. Since recoil cross-sections when using Li ions as projectiles are not well known, the energy dependent ratio between the experimental yield and the yield calculated using the Rutherford recoil cross-section was obtained from an ERDA spectrum of a thick polyimide (Kapton) sample. It was estimated that this ratio does not significantly depend on sample composition. Therefore it was used for correction of measured spectra analyzed by existing simulation and evaluation programs in which the Rutherford recoil cross-sections were applied. The correction procedure has been verified in round-robin measurements of well-characterized Si:H thin layers. Application of the method for determination of a hydrogen depth concentration profile in hydrogen-containing graphite samples is presented.

  13. Hydrogen analysis for granite using proton-proton elastic recoil coincidence spectrometry.

    PubMed

    Komatsubara, T; Sasa, K; Ohshima, H; Kimura, H; Tajima, Y; Takahashi, T; Ishii, S; Yamato, Y; Kurosawa, M

    2008-07-01

    In an effort to develop DS02, a new radiation dosimetry system for the atomic bomb survivors of Hiroshima and Nagasaki, measurements of neutron-induced activities have provided valuable information to reconstruct the radiation situation at the time of the bombings. In Hiroshima, the depth profile of (152)Eu activity measured in a granite pillar of the Motoyasu Bridge (128 m from the hypocenter) was compared with that calculated using the DS02 methodology. For calculation of the (152)Eu production due to the thermal-neutron activation reaction, (151)Eu(n,gamma)(152)Eu, information on the hydrogen content in granite is important because the transport and slowing-down process of neutrons penetrating into the pillar is strongly affected by collisions with the protons of hydrogen. In this study, proton-proton elastic recoil coincidence spectrometry has been used to deduce the proton density in the Motoyasu pillar granite. Slices of granite samples were irradiated by a 20 MeV proton beam, and the energies of scattered and recoil protons were measured with a coincidence method. The water concentration in the pillar granite was evaluated to be 0.30 +/- 0.07%wt. This result is consistent with earlier data on adsorptive water (II) and bound water obtained by the Karl Fisher method. PMID:18509666

  14. Nuclear Microprobe using Elastic Recoil Detection (ERD) for Hydrogen Profiling in High Temperature Protonic Conductors

    NASA Technical Reports Server (NTRS)

    Berger, Pascal; Sayir, Ali; Berger, Marie-Helene

    2004-01-01

    The interaction between hydrogen and various high temperature protonic conductors (HTPC) has not been clearly understood due to poor densification and unreacted secondary phases. the melt-processing technique is used in producing fully dense simple SrCe(0.9)Y (0.10) O(3-delta) and complex Sr3Ca(1+x)Nb(2+x)O(9-delta) perovskites that can not be achieved by solid-state sintering. the possibilities of ion beam analysis have been investigated to quantify hydrogen distribution in HTPC perovskites subjected to water heat treatment. Nuclear microprobe technique is based on the interactions of a focused ion beam of MeV light ions (H-1, H-2, He-3, He-4,.) with the sample to be analyzed to determine local elemental concentrations at the cubic micrometer scale, the elastic recoil detection analysis technique (ERDA) has been carried out using He-4(+) microbeams and detecting the resulting recoil protons. Mappings of longitudinal sections of water treated SrCeO3 and Sr(Ca(1/3)Nb(2/3))O3 perovskites have been achieved, the water treatment strongly alters the surface of simple SrCe(0.9)Y(0.10)O(3-delta) perovskite. From Rutherford Back Scattering measurements (RBS), both Ce depletion and surface re-deposition is evidenced. the ERDA investigations on water treated Sr3Ca(1+x)Nb(2+x)O(9-delta) perovskite did not exhibit any spatial difference for the hydrogen incorporation from the surface to the centre. the amount of hydrogen incorporation for Sr3Ca(1+x)Nb(2+x)O(9-delta) was low and required further development of two less conventional techniques, ERDA in forward geometry and forward elastic diffusion H-1(p,p) H-1 with coincidence detection.

  15. Elastic Recoil after Balloon Angioplasty in Hemodialysis Accesses: Does It Actually Occur and Is It Clinically Relevant?

    PubMed

    Rajan, Dheeraj K; Sidhu, Arshdeep; Noel-Lamy, Maxime; Mahajan, Ashish; Simons, Martin E; Sniderman, Kenneth W; Jaskolka, Jeffrey; Tan, Kong Teng

    2016-06-01

    Purpose To qualify and quantify elastic recoil and determine its effect on access patency. Materials and Methods Research ethics board approval was obtained and all patients signed an informed consent form. This was a prospective, nonrandomized study of mature accesses that underwent balloon percutaneous transluminal angioplasty (PTA) between January 2009 and December 2012. After PTA, completion fistulography was performed at 0-, 5-, 10-, and 15-minute intervals. From Digital Imaging and Communications in Medicine images, percentage of lesion stenosis before and after PTA was measured at each time point. A total of 76 patients (44 men, 32 women; mean age, 59.6 years) were enrolled and underwent 154 PTAs in 56 grafts and 98 fistulas. Venous elastic recoil was defined as recurrent luminal narrowing greater than 50% within 15 minutes after full effacement of the stenosis by the angioplasty balloon. Data collected included sex, age, access type and location, lesion location, length, and time to next intervention. Access patency was estimated by using Kaplan-Meier survival method, association of variables with the risk of loss of patency was assessed by using a Cox proportional hazards model, and a multiple variable model was examined by considering all variables. Results Technical success of PTA with less than 30% residual stenosis was 78%. By 15 minutes, 15.6% (24 of 154) of treated lesions recurrently narrowed by more than 50%, with a majority observed at 5 minutes (15 of 24). Technical failure of PTA was predictive of elastic recoil (P < .001), as was cephalic arch stenosis in fistulas (P = .047) and autogenous fistulas (P = .04). Elastic recoil, when it did occur, did not influence patency. Six-month primary patency was 34.8% in grafts and 47.1% in fistulas. Conclusion Venous elastic recoil after PTA of stenoses in hemodialysis access circuits is common, but its occurrence does not influence access primary patency after PTA. (©) RSNA, 2015. PMID:26694051

  16. A gas ionisation detector in the axial (Bragg) geometry used for the time-of-flight elastic recoil detection analysis

    SciTech Connect

    Siketić, Zdravko; Skukan, Natko; Bogdanović Radović, Iva

    2015-08-15

    In this paper, time-of-flight elastic recoil detection analysis spectrometer with a newly constructed gas ionization detector for energy detection is presented. The detector is designed in the axial (Bragg) geometry with a 3 × 3 array of 50 nm thick Si{sub 3}N{sub 4} membranes as an entrance window. 40 mbar isobutane gas was sufficient to stop a 30 MeV primary iodine beam as well as all recoils in the detector volume. Spectrometer and detector performances were determined showing significant improvement in the mass and energy resolution, respectively, comparing to the spectrometer with a standard silicon particle detector for an energy measurement.

  17. Rutherford forward scattering and elastic recoil detection (RFSERD) as a method for characterizing ultra-thin films

    DOE PAGESBeta

    Lohn, Andrew J.; Doyle, Barney L.; Stein, Gregory J.; Mickel, Patrick R.; Stevens, Jim E.; Marinella, Matthew J.

    2014-04-03

    We present a novel ion beam analysis technique combining Rutherford forward scattering and elastic recoil detection (RFSERD) and demonstrate its ability to increase efficiency in determining stoichiometry in ultrathin (5-50 nm) films as compared to Rutherford backscattering. In the conventional forward geometries, scattering from the substrate overwhelms the signal from light atoms but in RFSERD, scattered ions from the substrate are ranged out while forward scattered ions and recoiled atoms from the thin film are simultaneously detected in a single detector. Lastly, the technique is applied to tantalum oxide memristors but can be extended to a wide range of materialsmore » systems.« less

  18. Rutherford forward scattering and elastic recoil detection (RFSERD) as a method for characterizing ultra-thin films

    SciTech Connect

    Lohn, Andrew J.; Doyle, Barney L.; Stein, Gregory J.; Mickel, Patrick R.; Stevens, Jim E.; Marinella, Matthew J.

    2014-04-03

    We present a novel ion beam analysis technique combining Rutherford forward scattering and elastic recoil detection (RFSERD) and demonstrate its ability to increase efficiency in determining stoichiometry in ultrathin (5-50 nm) films as compared to Rutherford backscattering. In the conventional forward geometries, scattering from the substrate overwhelms the signal from light atoms but in RFSERD, scattered ions from the substrate are ranged out while forward scattered ions and recoiled atoms from the thin film are simultaneously detected in a single detector. Lastly, the technique is applied to tantalum oxide memristors but can be extended to a wide range of materials systems.

  19. Elastic recoil can either amplify or attenuate muscle-tendon power, depending on inertial vs. fluid dynamic loading.

    PubMed

    Richards, Christopher T; Sawicki, Gregory S

    2012-11-21

    Frog jumps exceed muscle power limits. To achieve this, a muscle may store elastic energy in tendon before it is released rapidly, producing 'power amplification' as tendon recoil assists the muscle to accelerate the load. Do the musculoskeletal modifications conferring power amplification help or hinder frog swimming? We used a Hill-type mathematical model of a muscle-tendon (MT) with contractile element (CE) and series elastic element (SEE) properties of frogs. We varied limb masses from 0.3 to 30 g, foot-fin areas from 0.005 to 50 cm(2) and effective mechanical advantage (EMA=in-lever/out-lever) from 0.025 to 0.1. 'Optimal' conditions produced power amplification of ~19% greater than the CE limit. Yet, other conditions caused ~80% reduction of MT power (power attenuation) due to SEE recoil absorbing power from (rather than adding to) the CE. The tendency for elastic recoil to cause power amplification vs. attenuation was load dependent: low fluid drag loads, high limb mass and EMA=0.1 caused power amplification whereas high drag, low mass and low EMA (=0.025) caused attenuation. Power amplification emerged when: (1) CE shortening velocity is 1/3V(max), (2) elastic energy storage is neither too high nor too low, and (3). peak inertial-drag force ratio ≥ ~1.5. Excessive elastic energy storage delayed the timing of recoil, causing power attenuation. Thus our model predicts that for fluid loads, the benefit from a compliant tendon is modest, and when the system is 'poorly tuned' (i.e., inappropriate EMA), MT power attenuation can be severe. PMID:22898554

  20. Hydrogen uptake in Zircaloy-2 reactor fuel claddings studied with elastic recoil detection

    SciTech Connect

    Rajasekhara, S.; Doyle, B. L.; Enos, D. G.; Clark, B. G.

    2013-04-19

    The recent trend towards a high burn-up discharge spent nuclear fuel necessitates a thorough understanding of hydrogen uptake in Zr-based cladding materials that encapsulate spent nuclear fuel. Although it is challenging to experimentally replicate exact conditions in a nuclear reactor that lead to hydrogen uptake in claddings, in this study we have attempted to understand the kinetics of hydrogen uptake by first electrolytically charging Zircaloy-2 (Zr-2) cladding material for various durations (100 to 2,600 s), and subsequently examining hydrogen ingress with elastic recoil detection (ERD) and transmission electron microscopy (TEM). To understand the influence of irradiation damage defects on hydrogen uptake, an analogous study was performed on ion - irradiated (0.1, 1 and 25 dpa) Zr-2. Analysis of ERD data from the un-irradiated Zr-2 suggests that the growth of the hydride layer is diffusion controlled, and preliminary TEM results support this assertion. In un-irradiated Zr-2, the diffusivity of hydrogen in the hydride phase was found to be approximately 1.1 Multiplication-Sign 10{sup -11} cm{sup 2}/s, while the diffusivity in the hydride phase for lightly irradiated (0.1 and 1 dpa) Zr-2 is an order of magnitude lower. Irradiation to 25 dpa results in a hydrogen diffusivity that is comparable to the un-irradiated Zr-2. These results are compared with existing literature on hydrogen transport in Zr - based materials.

  1. Heavy ion elastic recoil detection analysis set up for electronic sputtering studies

    NASA Astrophysics Data System (ADS)

    Ghosh, S.; Avasthi, D. K.; Tripathi, A.; Kabiraj, D.; Sugathan, P.; Chaudhary, G. K.; Barua, P.

    2006-04-01

    Heavy ion elastic recoil detection analysis (ERDA) set up with a large solid angle (greater than or similar to 4.8 msr) Delta E - E position-sensitive telescope detector is developed at Inter University Accelerator Centre as a dedicated facility for the study of electronic sputtering of thin films under swift heavy ion (SHI) irradiation. The detector consists of a gas ionization chamber (Delta E ) and a solid-state surface barrier detector ( E ) housed in a same assembly. The electronic sputtering yield (atoms/ion) is determined by analyzing on-line fluence-dependent ERDA data obtained from a variety of thin films. Large erosion (> 10 5 atoms/ion) of carbon from a-C:H by 150 MeV Ag 13+ ions, evolution of nitrogen (greater than or similar to 880 atoms/ion) from copper nitride and depletion of oxygen (greater than or similar to 1000 atoms/ion) from copper oxide film under 200 MeV Au 15+ ion impact are studied and reported in this work. The electronic sputtering of these materials is discussed on the basis of the thermal spike model of SHI and solid interaction.

  2. Detection Efficiency of a ToF Spectrometer from Heavy-Ion Elastic Recoil Detection

    SciTech Connect

    Barbara, E. de; Marti, G. V.; Capurro, O. A.; Fimiani, L.; Mingolla, M. G.; Negri, A. E.; Arazi, A.; Figueira, J. M.; Pacheco, A. J.; Martinez Heimann, D.; Carnelli, P. F. F.; Fernandez Niello, J. O.

    2010-08-04

    The detection efficiency of a time-of-flight system based on two micro-channel plates (MCP) time zero detectors plus a conventional silicon surface barrier detector was obtained from heavy ion elastic recoil measurements (this ToF spectrometer is mainly devoted to measurements of total fusion cross section of weakly bound projectiles on different mass-targets systems). In this work we have used beams of {sup 7}Li, {sup 16}O, {sup 32}S and {sup 35}Cl to study the mass region of interest for its application to measurements fusion cross sections in the {sup 6,7}Li+{sup 27}Al systems at energies around and above the Coulomb barrier (0.8V{sub B{<=}}E{<=}2.0V{sub B}). As the efficiency of a ToF spectrometer is strongly dependent on the energy and mass of the detected particles, we have covered a wide range of the scattered particle energies with a high degree of accuracy at the lowest energies. The different experimental efficiency curves obtained in that way were compared with theoretical electronic stopping power curves on carbon foils and were applied.

  3. Potku - New analysis software for heavy ion elastic recoil detection analysis

    NASA Astrophysics Data System (ADS)

    Arstila, K.; Julin, J.; Laitinen, M. I.; Aalto, J.; Konu, T.; Kärkkäinen, S.; Rahkonen, S.; Raunio, M.; Itkonen, J.; Santanen, J.-P.; Tuovinen, T.; Sajavaara, T.

    2014-07-01

    Time-of-flight elastic recoil detection (ToF-ERD) analysis software has been developed. The software combines a Python-language graphical front-end with a C code computing back-end in a user-friendly way. The software uses a list of coincident time-of-flight-energy (ToF-E) events as an input. The ToF calibration can be determined with a simple graphical procedure. The graphical interface allows the user to select different elements and isotopes from a ToF-E histogram and to convert the selections to individual elemental energy and depth profiles. The resulting sample composition can be presented as relative or absolute concentrations by integrating the depth profiles over user-defined ranges. Beam induced composition changes can be studied by displaying the event-based data in fractions relative to the substrate reference data. Optional angular input data allows for kinematic correction of the depth profiles. This open source software is distributed under the GPL license for Linux, Mac, and Windows environments.

  4. Hypo-Elastic Model for Lung Parenchyma

    SciTech Connect

    Freed, Alan D.; Einstein, Daniel R.

    2012-03-01

    A simple elastic isotropic constitutive model for the spongy tissue in lung is derived from the theory of hypoelasticity. The model is shown to exhibit a pressure dependent behavior that has been interpreted by some as indicating extensional anisotropy. In contrast, we show that this behavior arises natural from an analysis of isotropic hypoelastic invariants, and is a likely result of non-linearity, not anisotropy. The response of the model is determined analytically for several boundary value problems used for material characterization. These responses give insight into both the material behavior as well as admissible bounds on parameters. The model is characterized against published experimental data for dog lung. Future work includes non-elastic model behavior.

  5. Azimuthal asymmetry of recoil electrons in neutrino-electron elastic scattering as signature of neutrino nature

    NASA Astrophysics Data System (ADS)

    Sobków, W.; Błaut, A.

    2016-05-01

    In this paper, we analyze the theoretically possible scenario beyond the standard model in order to show how the presence of the exotic scalar, tensor, {V}+{A} weak interactions in addition to the standard vector-axial ({V}-{A}) ones may help to distinguish the Dirac from Majorana neutrinos in the elastic scattering of an (anti)neutrino beam off the unpolarized electrons in the relativistic limit. We assume that the incoming (anti)neutrino beam comes from the polarized muon decay at rest and is the left-right chiral superposition with assigned direction of the transversal spin polarization with respect to the production plane. Our analysis is carried out for the flavour (current) neutrino eigenstates. It means that the transverse neutrino polarization estimates are the same both for the Dirac and Majorana cases. We display that the azimuthal asymmetry in the angular distribution of recoil electrons is generated by the interference terms between the standard and exotic couplings, which are proportional to the transversal (anti)neutrino spin polarization and independent of the neutrino mass. This asymmetry for the Majorana neutrinos is larger than for the Dirac ones. We also indicate the possibility of utilizing the azimuthal asymmetry measurements to search for the new CP-violating phases. Our study is based on the assumption that the possible detector (running for 1 year) has the shape of a flat circular ring, while the intense neutrino source is located in the centre of the ring and polarized perpendicularly to the ring. In addition, the large low-threshold, real-time detector is able to measure with a high resolution both the polar angle and the azimuthal angle of outgoing electron momentum. Our analysis is model-independent and consistent with the current upper limits on the non-standard couplings.

  6. Computational fluid dynamics modeling of airflow inside lungs using heterogenous anisotropic lung tissue elastic properties.

    PubMed

    Ilegbusi, Olusegun; Li, Ziang; Min, Yugang; Meeks, Sanford; Kupelian, Patrick; Santhanam, Anand P

    2012-01-01

    The aim of this paper is to model the airflow inside lungs during breathing and its fluid-structure interaction with the lung tissues and the lung tumor using subject-specific elastic properties. The fluid-structure interaction technique simultaneously simulates flow within the airway and anisotropic deformation of the lung lobes. The three-dimensional (3D) lung geometry is reconstructed from the end-expiration 3D CT scan datasets of humans with lung cancer. The lung is modeled as a poro-elastic medium with anisotropic elastic property (non-linear Young's modulus) obtained from inverse lung elastography of 4D CT scans for the same patients. The predicted results include the 3D anisotropic lung deformation along with the airflow pattern inside the lungs. The effect is also presented of anisotropic elasticity on both the spatio-temporal volumetric lung displacement and the regional lung hysteresis. PMID:22356987

  7. Elasticity of excised dog lung parenchyma

    NASA Technical Reports Server (NTRS)

    Vawter, D. L.; Fung, Y. C.; West, J. B.

    1978-01-01

    An optical-electromechanical system is used to measure the force-deformation behavior of biaxially loaded rectangular slabs of excised dog lung parenchyma. In the course of the study, the effects of time, the consistency of reference lengths and areas, the presence of hysteresis, the necessity of preconditioning, the repeatability of results, the effects of lateral load, the effect of strain rate, the effect of pH, the influence of temperature, and the variations among specimens are considered. A new finding is that there is a change in elastic behavior when the tissue undergoes a compressive strain. When the tissue is in tension, increasing the lateral load decreases the compliance, whereas the opposite is true when compressive strain is present.

  8. Relationship between early diastolic intraventricular pressure gradients, an index of elastic recoil, and improvements in systolic and diastolic function

    NASA Technical Reports Server (NTRS)

    Firstenberg, M. S.; Smedira, N. G.; Greenberg, N. L.; Prior, D. L.; McCarthy, P. M.; Garcia, M. J.; Thomas, J. D.

    2001-01-01

    BACKGROUND: Early diastolic intraventricular pressure gradients (IVPGs) have been proposed to relate to left ventricular (LV) elastic recoil and early ventricular "suction." Animal studies have demonstrated relationships between IVPGs and systolic and diastolic indices during acute ischemia. However, data on the effects of improvements in LV function in humans and the relationship to IVPGs are lacking. METHODS AND RESULTS: Eight patients undergoing CABG and/or infarct exclusion surgery had a triple-sensor high-fidelity catheter placed across the mitral valve intraoperatively for simultaneous recording of left atrial (LA), basal LV, and apical LV pressures. Hemodynamic data obtained before bypass were compared with those with similar LA pressures and heart rates obtained after bypass. From each LV waveform, the time constant of LV relaxation (tau), +dP/dt(max), and -dP/dt(max) were determined. Transesophageal echocardiography was used to determined end-diastolic (EDV) and end-systolic (ESV) volumes and ejection fractions (EF). At similar LA pressures and heart rates, IVPG increased after bypass (before bypass 1.64+/-0.79 mm Hg; after bypass 2.67+/-1.25 mm Hg; P<0.01). Significant improvements were observed in ESV, as well as in apical and basal +dP/dt(max), -dP/dt(max), and tau (each P<0.05). Overall, IVPGs correlated inversely with both ESV (IVPG=-0.027[ESV]+3.46, r=-0.64) and EDV (IVPG=-0.027[EDV]+4.30, r=-0.70). Improvements in IVPGs correlated with improvements in apical tau (Deltatau =5.93[DeltaIVPG]+4.76, r=0.91) and basal tau (Deltatau =2.41[DeltaIVPG]+5.13, r=-0.67). Relative changes in IVPGs correlated with changes in ESV (DeltaESV=-0.97[%DeltaIVPG]+23.34, r=-0.79), EDV (DeltaEDV=-1.16[%DeltaIVPG]+34.92, r=-0.84), and EF (DeltaEF=0.38[%DeltaIVPG]-8.39, r=0.85). CONCLUSIONS: Improvements in LV function also increase IVPGs. These changes in IVPGs, suggestive of increases in LV suction and elastic recoil, correlate directly with improvements in LV relaxation

  9. Implementation of heavy-ion elastic recoil detection analysis at JANNUS-Saclay for quantitative helium depth profiling

    NASA Astrophysics Data System (ADS)

    Loussouarn, T.; Beck, L.; Trocellier, P.; Brimbal, D.; Leprêtre, F.; Bordas, E.; Vaubaillon, S.; Serruys, Y.; Lefaix-Jeuland, H.

    2015-10-01

    Quantitative depth profiling measurements of implanted light elements is an important issue for electronics and nuclear applications. Conventional elastic recoil detection analysis (ERDA) has been improved by using heavy ions as incident particles for quantitatively profiling helium in materials. A new system has been implemented on the triple beam irradiation platform JANNUS at Saclay devoted to carry out HI-ERDA measurements. This device is dedicated to helium depth profiling using a 15 MeV 16O5+ incident ion beam. Capabilities of the technique (quantitative analysis, resolution and limit of detection) were tested on samples of known composition. For the first time, 4He depth profiles in pure α-iron, as-implanted and annealed, are obtained. HI-ERDA measurements have shown that helium release in pure α-iron can be described by a succession of two steps, the first having a slow kinetics below 700 °C and the second with a fast kinetics above 700 °C.

  10. Dynamic measurement of the helium concentration of evolving tungsten nanostructures using Elastic Recoil Detection during plasma exposure

    NASA Astrophysics Data System (ADS)

    Woller, K. B.; Whyte, D. G.; Wright, G. M.

    2015-08-01

    Helium (He) concentration depth profiles of evolving tungsten (W) nanostructures have been measured for the first time using in situ Elastic Recoil Detection (ERD) throughout plasma irradiation. Exposures resulting in fuzzy and non-fuzzy surfaces were analyzed in order to illuminate the role of He during the development of these surface morphologies. ERD was performed on samples with surface temperatures from Ts = 530-1100 K and irradiated by He flux densities of ΓHe ∼ 1020-1022 m-2 s-1. He concentration profiles in samples that developed either non-fuzzy or fuzzy surfaces are uniformly shaped with concentrations of 1.5-7 at.%, which is presumed to be too low for pressure driven growth models. Therefore, surface morphology changes are not perpetuated by continuous bubble bursting deformation. Also, a threshold in He flux density above 1020 m-2 s-1 is suggested by using in situ ERD to monitor the depth profile evolution of the He-rich layer while changing the flux during exposure.

  11. Elastic recoil cross section determination of deuterium by helium-4 ions at 30° with the energy range of 2.6-7.4 MeV

    NASA Astrophysics Data System (ADS)

    Han, Zhibin; Hao, Wanli; Wang, Chunjie; Shi, Liqun

    2016-05-01

    The elastic recoil cross section for D(4He, D) 4He was determined at a recoil angle of 30° over an incident helium energy range from 2.6 to 7.4 MeV. A thin solid target Ta/TiDx/Si used for cross section measurement was prepared by direct current magnetron sputtering, and it was so stable to ion beam bombardment that nearly no deuterium loss (less than 0.2%) exists over the whole experiment. A relative determination method is adopted in this measurement. It can avoid the error from the beam dose and the solid angle of the detectors and it is also free to direct measurement of D content in the film. The total uncertainty in the cross section determination is less than 5%.

  12. Minimizing the cost of locomotion with inclined trunk predicts crouched leg kinematics of small birds at realistic levels of elastic recoil.

    PubMed

    Rode, Christian; Sutedja, Yefta; Kilbourne, Brandon M; Blickhan, Reinhard; Andrada, Emanuel

    2016-02-01

    Small birds move with pronograde trunk orientation and crouched legs. Although the pronograde trunk has been suggested to be beneficial for grounded running, the cause(s) of the specific leg kinematics are unknown. Here we show that three charadriiform bird species (northern lapwing, oystercatcher, and avocet; great examples of closely related species that differ remarkably in their hind limb design) move their leg segments during stance in a way that minimizes the cost of locomotion. We imposed measured trunk motions and ground reaction forces on a kinematic model of the birds. The model was used to search for leg configurations that minimize leg work that accounts for two factors: elastic recoil in the intertarsal joint, and cheaper negative muscle work relative to positive muscle work. A physiological level of elasticity (∼ 0.6) yielded segment motions that match the experimental data best, with a root mean square of angular deviations of ∼ 2.1 deg. This finding suggests that the exploitation of elastic recoil shapes the crouched leg kinematics of small birds under the constraint of pronograde trunk motion. Considering that an upright trunk and more extended legs likely decrease the cost of locomotion, our results imply that the cost of locomotion is a secondary movement criterion for small birds. Scaling arguments suggest that our approach may be utilized to provide new insights into the motion of extinct species such as dinosaurs. PMID:26643087

  13. Studies of electrochemical oxidation of Zircaloy nuclear reactor fuel cladding using time-of-flight-energy elastic recoil detection analysis

    NASA Astrophysics Data System (ADS)

    Whitlow, H. J.; Zhang, Y.; Wang, Y.; Winzell, T.; Simic, N.; Ahlberg, E.; Limbäck, M.; Wikmark, G.

    2000-03-01

    The trend towards increased fuel burn-up and higher operating temperatures in order to achieve more economic operation of nuclear power plants places demands on a better understanding of oxidative corrosion of Zircaloy (Zry) fuel rod cladding. As part of a programme to study these processes we have applied time-of-flight-energy elastic recoil detection (ToF-E ERD), electrochemical impedance measurements and scanning electron microscopy to quantitatively characterise thin-oxide films corresponding to the pre-transition oxidation regime. Oxide films of different nominal thickness in the 9-300 nm range were grown on a series of rolled Zr and Zry-2 plates by anodisation in dilute H 2SO 4 with applied voltages. The dielectric thickness of the oxide layer was determined from the electrochemical impedance measurements and the surface topography characterised by scanning electron microscopy. ToF-E ERD with a 60 MeV 127I 11+ ion beam was used to determine the oxygen content and chemical composition of the oxide layer. In the Zr samples, the oxygen content (O atom cm -2) that was determined by ERD was closely similar to the O content derived from impedance measurements from the dielectric film. The absolute agreement was well within the uncertainty associated with the stopping powers. Moreover, the measured composition of the thick oxide layers corresponded to ZrO 2 for the films thicker than 65 nm where the oxide layer was resolved in the ERD depth profile. Zry-2 samples exhibited a similar behaviour for small thickness ( ⩽130 nm) but had an enhanced O content at larger thicknesses that could be associated either with enhanced rough surface topography or porous oxide formation that was correlated with the presence of Second Phase Particles (SPP) in Zry-2. The concentration of SPP elements (Fe, Cr, Ni) in relation to Zr was the same in the outer 9×10 17 atom cm -2 of oxide as in the same thickness of metal. The results also revealed the presence of about 1 at.% 32S in the

  14. Improvements in Fabrication of Elastic Scattering Foils Used to Measure Neutron Yield by the Magnetic Recoil Spectrometer

    DOE PAGESBeta

    Reynolds, H. G.; Schoff, M. E.; Farrell, M. P.; Gatu Johnson, M.; Bionta, R. M.; Frenje, J. A.

    2016-08-01

    The magnetic recoil spectrometer uses a deuterated polyethylene polymer (CD2) foil to measure neutron yield in inertial confinement fusion experiments. Higher neutron yields in recent experiments have resulted in primary signal saturation in the detector CR-39 foils, necessitating the fabrication of thinner CD2 foils than established methods could provide. A novel method of fabricating deuterated polymer foils is described. The resulting foils are thinner, smoother, and more uniform in thickness than the foils produced by previous methods. Here, these new foils have successfully been deployed at the National Ignition Facility, enabling higher neutron yield measurements than previous foils, with nomore » primary signal saturation.« less

  15. Determination of concentration profiles by elastic recoil detection with a ΔE-E gas telescope and high energy incident heavy ions

    NASA Astrophysics Data System (ADS)

    Stoquert, J. P.; Guillaume, G.; Hage-Ali, M.; Grob, J. J.; Ganter, C.; Siffert, P.

    1989-12-01

    The Elastic Recoil Detection (ERD) method has been used to determine the profile of a wide range of elements simultaneously in a thin layer (1μm) with a depth resolution of a few hundred Å and high sensitivity. Z separation is achieved by a ΔE(gas)-E(solid) telescope. Results for 127I (up to 240 MeV) incident ions used to profile thin films of dielectrics (SiOxNyHz), amorphous semiconductors (a-GaAs: H) and superconductors (YBaCuO, BiSrCaCuO) are reported. It has been considered previously that ERD is of interest for analysis of light elements. We show that high energy heavy incident ions extend the field of application of the ERD method to all elements with an approximately constant depth resolution and sensitivity.

  16. An Implicit Elastic Theory for Lung Parenchyma☆,☆☆

    PubMed Central

    Freed, Alan D.; Einstein, Daniel R.

    2012-01-01

    The airways and parenchyma of lung experience large deformations during normal respiration. Spatially accurate predictions of airflow patterns and aerosol transport therefore require respiration to be modeled as a fluid-structure interaction problem. Such computational models in turn require constitutive models for the parencyhma that are both accurate and efficient. Herein, an implicit theory of elasticity is derived from thermodynamics to meet this need, leading to a generic template for strain-energy that is shown to be an exact analogue for the well-known Fung model that is the root of modern constitutive theory of tissues. To support this theory, we also propose a novel definition of Lagrangian strain rate. Unlike the classic definition of Lagrangian strain rate, this new definition is separable into volumetric and deviatoric terms, a separation that is both mathematically and physically justified. Within this framework, a novel material model capable of describing the elastic contribution of the nonlinear response of parenchyma is constructed and characterized against published data. PMID:23144500

  17. Mg segregation in Mg-rich Mg-Ni switchable mirror studied by Rutherford backscattering, elastic recoil detection analysis, and nuclear reaction analysis

    SciTech Connect

    Sekiba, D.; Horikoshi, M.; Abe, S.; Ishii, S.

    2009-12-01

    Pd/Mg{sub 3.3}Ni films were prepared by dc sputtering deposition on three different substrates of glass, diamondlike carbon/Si, and Si. Hydrogenation and dehydrogenation cycles were performed on these samples simultaneously. The optical switching property due to the hydrogenation and dehydrogenation was monitored by the transmission of laser light via the glass substrate. The switching ability was totally lost after 120 cycles. We made comparative study of the composition change between the new (as-deposited) and old (after 120 switching cycles) samples by Rutherford backscattering (RBS), elastic recoil detection analysis (ERDA), and nuclear reaction analysis (NRA). From the RBS results we found out the segregation of a Mg layer between the Pd cap layer and the rest of the Mg-Ni layer. At the Pd/Mg interface in the old sample, thin MgO layer formed probably during the dehydrogenation process with O{sub 2}. ERDA showed that there is much hydrogen in the old sample. NRA displayed the depth profiles of hydrogen distribution in the old sample. It is revealed that much hydrogen is accumulated at the interface between the Pd cap layer and the segregated Mg layer. It can be concluded that the formations of oxide and hydride of the segregated Mg layer are the main reasons for the degradation of the Mg{sub 3.3}Ni switchable mirror.

  18. Dynamic Measurements of Hydrogen and Lithium Distributions in Lithium-Cobalt-Oxide Films with Charging and Heating Using Elastic Recoil Detection Techniques

    NASA Astrophysics Data System (ADS)

    Tsuchiya, B.; Morita, K.; Iriyama, Y.; Majima, T.; Tsuchida, H.

    The migrations of lithium (Li) as well as hydrogen (H) in multi-layers thin films of Au/LiCoO2 (thickness: approximately 42 nm/80 nm), deposited onto one face of Li1.4Ti2Si0.4P2.6O12-AlPO4 (LATP) substrates, were dynamically observed with electric charging as well as isochronal annealing in vacuum by combining elastic recoil detection (ERD) analysis with Rutherford backscattering spectrometry (RBS)with 9.0-MeV O4+ ion-probe beams. The ERD spectra clearly revealed that Li atoms of approximately 9.4 at% migrated from the LiCoO2 surface to the LiCoO2/LATP interface with H absorption by a charge of approximately 0.48 e/cm2, which the acquiredvoltage was1.65 V. In addition, the diffusion of Li atoms to the LATP bulk occurred with H release by isochronal annealing at only 323 K for 10 min.The presence of H significantly influences the Li+ ion conduction for the Li-battery systems.

  19. Hydrogen ion-implantation induced low resistive layer in KNbO3 bulk single crystal: Evaluation by elastic recoil detection analysis

    NASA Astrophysics Data System (ADS)

    Shinkawa, A.; Shibasaki, Y.; Nishimura, T.; Tanuma, C.; Kuriyama, K.

    2016-03-01

    Origins of low resistivity in H-ion implanted KNbO3 bulk single crystals are studied by elastic recoil detection analysis (ERDA) and Van der Pauw methods. The H-ion implantation (peak ion fluence: 5.0 × 1015 cm-2) into KNbO3 is performed using a 500 keV implanter. The sheet resistance decreases from ∼108 Ω/□ for an un-implanted KNbO3 sample to 2.33 × 105 Ω/□ for as-implanted, 2.29 × 105 Ω/□ for 100 °C annealed, and 4.25 × 105 Ω/□ for 150 °C annealed samples, respectively. The ERDA experiment using the 1.5 MeV-4He+ beam can evaluate hydrogen from the surface to around 60 nm. The hydrogen concentration near the surface estimated using the 1.5 MeV helium beam is 5.1 × 1014 cm-2 for un-implanted KNbO3 sample, 5.6 × 1014 cm-2 for as-implanted, 3.4 × 1014 cm-2 for 150 °C annealed samples, respectively, indicating that a part of hydrogen is diffused out by annealing. The low resistive layer induced in H-ion implanted KNbO3 suggests the existence of a shallow energy level related to the complex defect consisting of hydrogen interstitial and the proton induced defect such as oxygen vacancy.

  20. Hydrogen interstitial in H-ion implanted ZnO bulk single crystals: Evaluation by elastic recoil detection analysis and electron paramagnetic resonance

    NASA Astrophysics Data System (ADS)

    Kaida, T.; Kamioka, K.; Nishimura, T.; Kuriyama, K.; Kushida, K.; Kinomura, A.

    2015-12-01

    The origins of low resistivity in H ion-implanted ZnO bulk single crystals are evaluated by elastic recoil detection analysis (ERDA), electron paramagnetic resonance (EPR), and Van der Pauw methods. The H-ion implantation (peak concentration: 5.0 × 1015 cm-2) into ZnO is performed using a 500 keV implanter. The maximum of the concentration of the implanted H estimated by a TRIM simulation is at 3600 nm in depth. The resistivity decreases from ∼103 Ω cm for un implanted ZnO to 6.5 Ω cm for as-implanted, 2.3 × 10-1 Ω cm for 200 °C annealed, and 3.2 × 10-1 Ω cm for 400 °C annealed samples. The ERDA measurements can evaluate the concentration of hydrogens which move to the vicinity of the surface (surface to 300 nm or 100 nm) because of the diffusion by the annealing at 200 °C and 400 °C. The hydrogen concentration near the surface estimated using the 2.0 MeV helium beam is ∼3.8 × 1013 cm-2 for annealed samples. From EPR measurements, the oxygen vacancy of +charge state (Vo+) is observed in as-implanted samples. The Vo+ related signal (g = 1.96) observed under no illumination disappears after successive illumination with a red LED and appears again with a blue light illumination. The activation energy of as-implanted, 200 °C annealed, and 400 °C annealed samples estimated from the temperature dependence of carrier concentration lies between 29 meV and 23 meV, suggesting the existence of H interstitial as a shallow donor level.

  1. Analysis of H in Natural and Experimental Nominally Anhydrous Minerals: A Comparison of Elastic Recoil Detection Analysis, Infrared and SIMS Measurements.

    NASA Astrophysics Data System (ADS)

    Withers, A. C.; Mosenfelder, J. L.; Bureau, H.; Raepsaet, C.; Hirschmann, M. M.

    2014-12-01

    Experiments to determine the H storage capacity of nominally anhydrous minerals (NAMs) can be used to place strong constraints on the degree of hydration required to initiate volatile fluxed melting in the mantle. Moreover, accurate measurements of H in NAMs from mantle xenoliths may be used to constrain the rheological properties of the source region. However, accurate measurements of H concentrations using infrared and ion beam techniques require mineral specific calibrations. Standardless measurements of H using elastic recoil detection analysis (ERDA) in some cases have provided valuable verification of calibrations for other techniques, but so far have had limited application to experimental samples owing to sample size and analytical background. Results of recent measurements of H in garnet, pyroxene and feldspar will be used to illustrate the potential of the technique. Some of the results we will present include the following: 1) Forsterites grown at 2 and 3 GPa in the MgO-Al2O3-SiO2-H2O system exhibit low frequency absorption bands in the OH stretching region between 3300 and 3400 cm-1, but very limited absorption at higher frequencies where the strongest absorption bands are usually seen for Al-free olivine. Analyses of H in these samples by ERDA will be used to develop a tentative site-specific molar absorption coefficient for the low frequency OH absorption band. 2) ERDA measurements of H in silicate glass standards verify previous determinations by Karl Fischer titration and FTIR spectroscopy, validating the ERDA technique. Samples of these rhyolitic glasses are available on request for use as analytical standards, and come with a compendium of analyses that have been used to characterize major and minor elemental composition and H content. 3) ERDA measurements of three homogeneous grossular garnets from East Africa show an excellent correlation (r2 = 1) with absorbance in the O-H stretching region and indicate an integral molar absorption coefficient

  2. Differential elastic responses to barrier-altering agonists in two types of human lung endothelium.

    PubMed

    Viswanathan, P; Ephstein, Y; Garcia, J G N; Cho, M; Dudek, S M

    2016-09-16

    Vascular integrity is primarily determined by endothelial cell (EC) cytoskeletal structure that is differentially regulated by various stimuli. In this study, atomic force microscopy (AFM) was used to characterize structural and mechanical properties in the cytoskeleton of cultured human pulmonary artery EC (HPAEC) and human lung microvascular EC (HLMVEC) by determining elastic properties (Young's modulus) in response to endogenous barrier protective agents sphingosine 1-phosphate (S1P) and hepatocyte growth factor (HGF), or the barrier disruptive molecule thrombin. Initial studies in unstimulated cells indicate higher baseline peripheral elastic modulus values in HPAEC (mean 2.9 KPa) than in HLMVEC (1.8 KPa). After 30 min of stimulation, S1P induced the highest Young's modulus increase (6.1 KPa) compared to the other barrier enhancing stimuli, HGF (5.8 KPa) and the pharmaceutical agent and S1P analog FTY720 (4.1 KPa). In contrast, the barrier disruptive agent thrombin decreased values from 2.5 KPa to 0.7 KPa depending on the cell type and treatment time. AFM topographical imaging supports these quantitative biophysical data regarding differential peripheral elastic properties in EC. Overall, these AFM studies provide novel insights into the biomechanical properties of human lung EC that regulate vascular barrier function and have potential applicability to pathophysiologic vascular leak syndromes such as acute lung injury. PMID:27473658

  3. Measurement and mathematical modelling of elastic and resistive lung mechanical properties studied at sinusoidal expiratory flow.

    PubMed

    Bitzén, Ulrika; Niklason, Lisbet; Göransson, Ingegerd; Jonson, Björn

    2010-11-01

    Elastic pressure/volume (P(el) /V) and elastic pressure/resistance (P(el) /R) diagrams reflect parenchymal and bronchial properties, respectively. The objective was to develop a method for determination and mathematical characterization of P(el) /V and P(el) /R relationships, simultaneously studied at sinusoidal flow-modulated vital capacity expirations in a body plethysmograph. Analysis was carried out by iterative parameter estimation based on a composite mathematical model describing a three-segment P(el) /V curve and a hyperbolic P(el) /R curve. The hypothesis was tested that the sigmoid P(el) /V curve is non-symmetric. Thirty healthy subjects were studied. The hypothesis of a non-symmetric P(el) /V curve was verified. Its upper volume asymptote was nearly equal to total lung capacity (TLC), indicating lung stiffness increasing at high lung volume as the main factor limiting TLC at health. The asymptotic minimal resistance of the hyperbolic P(el) /R relationship reflected lung size. A detailed description of both P(el) /V and P(el) /R relationships was simultaneously derived from sinusoidal flow-modulated vital capacity expirations. The nature of the P(el) /V curve merits the use of a non-symmetric P(el) /V model. PMID:20726995

  4. Accuracy of non-rigid registration for local analysis of elasticity restrictions of the lungs

    NASA Astrophysics Data System (ADS)

    Stein, Daniel; Tetzlaff, Ralf; Wolf, Ivo; Meinzer, Hans-Peter

    2009-02-01

    Diseases of the lung often begin with regionally limited changes altering the tissue elasticity. Therefore, quantification of regional lung tissue motion would be desirable for early diagnosis, treatment monitoring, and follow-up. Dynamic MRI can capture such changes, but quantification requires non-rigid registration. However, analysis of dynamic MRI data of the lung is challenging due to inherently low image signal and contrast. Towards a computer-assisted quantification for regional lung diseases, we have evaluated two Demons-based registration methods for their accuracy in quantifying local lung motion on dynamic MRI data. The registration methods were applied on masked image data, which were pre-segmented with a graph-cut algorithm. Evaluation was performed on five datasets from healthy humans with nine time frames each. As gold standard, manually defined points (between 8 and 24) on prominent landmarks (essentially vessel structures) were used. The distance between these points and the predicted landmark location as well as the overlap (Dice coefficient) of the segmentations transformed with the deformation field were calculated. We found that the Demons algorithm performed better than the Symmetric Forces Demons algorithm with respect to average landmark distance (6.5 mm +/- 4.1 mm vs. 8.6 mm +/- 6.1 mm), but comparable regarding the Dice coefficient (0.946 +/- 0.018 vs. 0.961 +/- 0.018). Additionally, the Demons algorithm computes the deformation in only 10 seconds, whereas the Symmetric Forces Demons algorithm takes about 12 times longer.

  5. Dietary iron deficiency compromises normal development of elastic fibers in the aorta and lungs of chicks.

    PubMed

    Hill, Charles H; Ashwell, Chris M; Nolin, Shelly J; Keeley, Fred; Billingham, Catherine; Hinek, Aleksander; Starcher, Barry

    2007-08-01

    Elastic fibers play a key role in the structure and function of numerous organs that require elasticity. Elastogenesis is a complex process in which cells first produce a microfibrillar scaffold, composed of numerous structural proteins, upon which tropoelastin assembles to be cross-linked into polymeric elastin. Recently, it was demonstrated that low concentrations of free iron upregulate elastin gene expression in cultured fibroblasts. The present studies were conducted to assess whether low-iron diets would affect the deposition of elastic fibers in an in vivo model. One-day-old chicks were fed semipurified diets containing 1.3 (low), 12 (moderate), and 24 (control) mg/kg of iron. After 3 wk, chicks in the low-iron group were underweight and anemic. Their aortas were smaller with significantly thinner walls than control chicks, yet elastin or collagen content did not decrease relative to total protein. They also demonstrated a significantly lower stress-strain resistance than the controls. Electron microscopy demonstrated that aortic and lung smooth muscle cells were vacuolated and surrounded by loose extracellular matrix and disorganized elastic lamellae with diffuse and fragmented networks of elastic fibers and microfibrils. Immunohistology demonstrated that fibrillin-3 (FBN3) was disorganized and markedly reduced in amount in aortas of the low-iron chicks. Elastin messenger RNA levels were not downregulated in the tissues from the low-iron-fed chicks; however, there was a significant reduction in expression of the FBN1 and FBN3 genes compared with control chicks. The studies indicate that iron deficiency had a pronounced negative effect on elastic fiber development and suggests that fibrillin may have an important role in this pathology. PMID:17634261

  6. Effect of bronchomotor tone on static mechanical properties of lung and ventilation distribution.

    PubMed

    Crawford, A B; Makowska, M; Engel, L A

    1987-12-01

    To study the relationship between bronchomotor tone, static mechanical properties of the lung, and ventilation distribution, we measured the pressure-volume (P-V) curve of the lung and several ventilatory indexes before and after intravenous atropine in eight normal subjects. The indexes of ventilation distribution were derived from multiple breath N2 washouts by a recently developed analysis (7,8). The latter not only provides a sensitive measure of overall ventilation inhomogeneity but distinguishes between the convection-dependent inhomogeneity (CDI) among larger lung units and that due to the interaction of convection and diffusion (DCDI) within the lung periphery. Atropine decreased lung elastic recoil but distensibility, as defined by the exponent (K) in the monoexponential analysis of the P-V data, was unchanged. The overall ventilation inhomogeneity increased by 37% after atropine (P less than 0.02) due to an increase in the CDI component. More importantly, there was a significant correlation between the loss of lung recoil (but not K) and each of the indexes of CDI among the subjects. There was no correlation between the changes in lung recoil and in DCDI. Our findings indicate that normal bronchomotor tone contributes to the elastic recoil of the lung. Furthermore, the tone is distributed in a way that enhances the uniformity of ventilation distribution among diffusion-independent lung units. Presumably this is achieved by minimizing interacinar intrinsic inequalities in static mechanical properties. PMID:3436864

  7. Changes in respiratory elastance after deep inspirations reflect surface film functionality in mice with acute lung injury.

    PubMed

    Takahashi, Ayuko; Bartolák-Suki, Erzsébet; Majumdar, Arnab; Suki, Béla

    2015-08-01

    Pulmonary surfactant reduces surface tension in the lung and prevents alveolar collapse. Following a deep inspiration (DI), respiratory elastance first drops then gradually increases due to surface film and tissue viscoelasticity. In acute lung injury (ALI), this increase is faster and governed by alveolar collapse due to increased surface tension. We hypothesized that the rate of increase in elastance reflects the deficiency of surfactant in the lung. To test this, mice were ventilated before (baseline) and after saline lavage obtained by injecting 0.8 ml and withdrawing 0.7 ml fluid (severe ALI) or injecting 0.1 ml (mild ALI). After two DIs, elastance was tracked for 10 min followed by a full lavage to assess surfactant proteins B (SP-B) and C (SP-C) content. Following 2 DIs, the increases in elastance during 10 min ventilation (ΔH) were 3.60 ± 0.61, 5.35 ± 1.04, and 8.33 ± 0.84 cmH2O/ml in baseline mice and mice with mild and severe ALI, respectively (P < 0.0001). SP-B and SP-C in the lavage fluid dropped by 32.4% and 24.9% in the mild and 50.4% and 39.6% in the severe ALI, respectively. Furthermore, ΔH showed a strong negative correlation with both SP-B (r(2) = 0.801) and SP-C (r(2) = 0.810) content. The ΔH was, however, much smaller when the lavage fluid also contained exogeneous SP-B and SP-C. Thus ΔH can be interpreted as an organ level measure of surface film functionality in lavage-induced ALI in mice. This method could prove useful in clinical situations such as diagnosing surfactant problems, monitoring recovery from lung injury or the effectiveness of surfactant therapy. PMID:26066828

  8. The HERMES recoil detector

    NASA Astrophysics Data System (ADS)

    Airapetian, A.; Aschenauer, E. C.; Belostotski, S.; Borisenko, A.; Bowles, J.; Brodski, I.; Bryzgalov, V.; Burns, J.; Capitani, G. P.; Carassiti, V.; Ciullo, G.; Clarkson, A.; Contalbrigo, M.; De Leo, R.; De Sanctis, E.; Diefenthaler, M.; Di Nezza, P.; Düren, M.; Ehrenfried, M.; Guler, H.; Gregor, I. M.; Hartig, M.; Hill, G.; Hoek, M.; Holler, Y.; Hristova, I.; Jo, H. S.; Kaiser, R.; Keri, T.; Kisselev, A.; Krause, B.; Krauss, B.; Lagamba, L.; Lehmann, I.; Lenisa, P.; Lu, S.; Lu, X.-G.; Lumsden, S.; Mahon, D.; Martinez de la Ossa, A.; Murray, M.; Mussgiller, A.; Nowak, W.-D.; Naryshkin, Y.; Osborne, A.; Pappalardo, L. L.; Perez-Benito, R.; Petrov, A.; Pickert, N.; Prahl, V.; Protopopescu, D.; Reinecke, M.; Riedl, C.; Rith, K.; Rosner, G.; Rubacek, L.; Ryckbosch, D.; Salomatin, Y.; Schnell, G.; Seitz, B.; Shearer, C.; Shutov, V.; Statera, M.; Steijger, J. J. M.; Stenzel, H.; Stewart, J.; Stinzing, F.; Trzcinski, A.; Tytgat, M.; Vandenbroucke, A.; Van Haarlem, Y.; Van Hulse, C.; Varanda, M.; Veretennikov, D.; Vilardi, I.; Vikhrov, V.; Vogel, C.; Yaschenko, S.; Ye, Z.; Yu, W.; Zeiler, D.; Zihlmann, B.

    2013-05-01

    For the final running period of HERA, a recoil detector was installed at the HERMES experiment to improve measurements of hard exclusive processes in charged-lepton nucleon scattering. Here, deeply virtual Compton scattering is of particular interest as this process provides constraints on generalised parton distributions that give access to the total angular momenta of quarks within the nucleon. The HERMES recoil detector was designed to improve the selection of exclusive events by a direct measurement of the four-momentum of the recoiling particle. It consisted of three components: two layers of double-sided silicon strip sensors inside the HERA beam vacuum, a two-barrel scintillating fibre tracker, and a photon detector. All sub-detectors were located inside a solenoidal magnetic field with a field strength of 1T. The recoil detector was installed in late 2005. After the commissioning of all components was finished in September 2006, it operated stably until the end of data taking at HERA end of June 2007. The present paper gives a brief overview of the physics processes of interest and the general detector design. The recoil detector components, their calibration, the momentum reconstruction of charged particles, and the event selection are described in detail. The paper closes with a summary of the performance of the detection system.

  9. The HERMES Recoil Detector

    SciTech Connect

    Kaiser, R.

    2006-07-11

    The HERMES Collaboration is installing a new Recoil Detector to upgrade the spectrometer for measurements of hard exclusive electron/positron scattering reactions, in particular deeply virtual Compton scattering. These measurements will provide access to generalised parton distributions and hence to the localisation of quarks inside hadrons and to their orbital angular momentum. The HERMES Recoil Detector consists of three active components: a silicon detector surrounding the target cell inside the beam vacuum, a scintillating fibre tracker and a photon detector consisting of three layers of tungsten/scintillator. All three detectors are located inside a solenoidal magnetic field of 1 Tesla. The Recoil Detector was extensively tested with cosmic muons over the summer of 2005 and is being installed in the winter of 2005/6 for data taking until summer 2007.

  10. High acceptance recoil polarimeter

    SciTech Connect

    The HARP Collaboration

    1992-12-05

    In order to detect neutrons and protons in the 50 to 600 MeV energy range and measure their polarization, an efficient, low-noise, self-calibrating device is being designed. This detector, known as the High Acceptance Recoil Polarimeter (HARP), is based on the recoil principle of proton detection from np[r arrow]n[prime]p[prime] or pp[r arrow]p[prime]p[prime] scattering (detected particles are underlined) which intrinsically yields polarization information on the incoming particle. HARP will be commissioned to carry out experiments in 1994.

  11. Lung mechanics in relation to radiographic category of coalworkers' simple pneumoconiosis

    PubMed Central

    Legg, S J; Cotes, J E; Bevan, Carol

    1983-01-01

    ABSTRACT The maximal expiratory flow/static transpulmonary pressure relationship and the maximal expiratory flow response to breathing oxyhelium were used to distinguish between loss of elastic recoil and narrowing of small airways in 36 lifelong non-smoking non-bronchitic South Wales coalminers. On average the miners showed significantly (p < 0·05) reduced lung elastic recoil when compared with 10 healthy similarly aged non-miners. The mean forced expiratory volume in one second and the forced expiratory flow response to oxyhelium at 50% of the vital capacity were significantly (p < 0·05) lower in 12 miners with radiographic categories 2 or 3 when compared with 24 similarly aged miners with radiographic categories 0 or 1. The miners with categories 2 or 3 coalworkers' simple pneumoconiosis (CWP) had worked underground for 10 years longer, and their mean residual volume, residual volume/total lung capacity ratio, volume of isoflow and critical transmural pressure were significantly higher (p < 0·05). The results indicate that in the prodromal and early stages of simple CWP (categories 0 and 1), the dominant pathophysiological abnormality is loss of elastic recoil suggesting the presence of “focal emphysema.” As simple CWP progresses to categories 2 and 3, the loss of recoil is maintained, and the small airways become narrower. These findings are consistent with the hypothesis that progression of simple CWP is associated with the development of both centrilobular emphysema and intrinsic narrowing of small airways. PMID:6824596

  12. Interpreting Recoil for Undergraduate Students

    ERIC Educational Resources Information Center

    Elsayed, Tarek A.

    2012-01-01

    The phenomenon of recoil is usually explained to students in the context of Newton's third law. Typically, when a projectile is fired, the recoil of the launch mechanism is interpreted as a reaction to the ejection of the smaller projectile. The same phenomenon is also interpreted in the context of the conservation of linear momentum, which is…

  13. Epithelial cell apoptosis causes acute lung injury masquerading as emphysema.

    PubMed

    Mouded, Majd; Egea, Eduardo E; Brown, Matthew J; Hanlon, Shane M; Houghton, A McGarry; Tsai, Larry W; Ingenito, Edward P; Shapiro, Steven D

    2009-10-01

    Theories of emphysema traditionally revolved around proteolytic destruction of extracellular matrix. Models have recently been developed that show airspace enlargement with the induction of pulmonary cell apoptosis. The purpose of this study was to determine the mechanism by which a model of epithelial cell apoptosis caused airspace enlargement. Mice were treated with either intratracheal microcystin (MC) to induce apoptosis, intratracheal porcine pancreatic elastase (PPE), or their respective vehicles. Mice from all groups were inflated and morphometry was measured at various time points. Physiology measurements were performed for airway resistance, tissue elastance, and lung volumes. The groups were further analyzed by air-saline quasistatic measurements, surfactant staining, and surfactant functional studies. Mice treated with MC showed evidence of reversible airspace enlargement. In contrast, PPE-treated mice showed irreversible airspace enlargement. The airspace enlargement in MC-treated mice was associated with an increase in elastic recoil due to an increase in alveolar surface tension. PPE-treated mice showed a loss of lung elastic recoil and normal alveolar surface tension, a pattern more consistent with human emphysema. Airspace enlargement that occurs with the MC model of pulmonary epithelial cell apoptosis displays physiology distinct from human emphysema. Reversibility, restrictive physiology due to changes in surface tension, and alveolar enlargement associated with heterogeneous alveolar collapse are most consistent with a mild acute lung injury. Inflation near total lung capacity gives the appearance of enlarged alveoli as neighboring collapsed alveoli exert tethering forces. PMID:19188661

  14. Rupture and recoil of bent-core liquid crystal filaments.

    PubMed

    Salili, S M; Ostapenko, T; Kress, O; Bailey, C; Weissflog, W; Harth, K; Eremin, A; Stannarius, R; Jákli, A

    2016-05-25

    The recoil process of free-standing liquid crystal filaments is investigated experimentally and theoretically. We focus on two aspects, the contraction speed of the filament and a spontaneously formed undulation instability. At the moment of rupture, the filaments buckle similarly to the classical Euler buckling of elastic rods. The tip velocity decays with decreasing filament length. The wavelength of buckling affinely decreases with the retracting filament tip. The energy gain related to the decrease of the total length and surface area of the filaments is mainly dissipated by layer rearrangements during thickening of the fibre. A flow back into the meniscus is relevant only in the final stage of the recoil process. We introduce a model for the quantitative description of the filament retraction speed. The dynamics of this recoil behaviour may find relevance as a model for biology-related filaments. PMID:27140824

  15. Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System Phase I: Hypo-Elastic Model for CFD Implementation

    SciTech Connect

    Freed, Alan D.; Einstein, Daniel R.

    2011-04-14

    An isotropic constitutive model for the parenchyma of lung has been derived from the theory of hypo-elasticity. The intent is to use it to represent the mechanical response of this soft tissue in sophisticated, computational, fluid-dynamic models of the lung. This demands that the continuum model be accurate, yet simple and effcient. An objective algorithm for its numeric integration is provided. The response of the model is determined for several boundary-value problems whose experiments are used for material characterization. The effective elastic, bulk, and shear moduli, and Poisson’s ratio, as tangent functions, are also derived. The model is characterized against published experimental data for lung. A bridge between this continuum model and a dodecahedral model of alveolar geometry is investigated, with preliminary findings being reported.

  16. Further insight into gravitational recoil

    SciTech Connect

    Lousto, Carlos O.; Zlochower, Yosef

    2008-02-15

    We test the accuracy of our recently proposed empirical formula to model the recoil velocity imparted to the merger remnant of spinning, unequal-mass black-hole binaries. We study three families of black-hole binary configurations, all with mass ratio q=3/8 (to nearly maximize the unequal-mass contribution to the kick) and spins aligned (or counter-aligned) with the orbital angular momentum, two with spin configurations chosen to minimize the spin-induced tangential and radial accelerations of the trajectories, respectively, and a third family where the trajectories are significantly altered by spin-orbit coupling. We find good agreement between the measured and predicted recoil velocities for the first two families, and reasonable agreement for the third. We also reexamine our original generic binary configuration that led to the discovery of extremely large spin-driven recoil velocities and inspired our empirical formula, and find rough agreement between the predicted and measured recoil speeds.

  17. Confocal microscopy for automatic texture analysis of elastic fibers in histologic preparations

    NASA Astrophysics Data System (ADS)

    Adam, R. L.; Vieira, G.; Ferro, D. P.; de Thomaz, A. A.; Cesar, C., L.; Metze, K.

    2009-07-01

    Elastic fibers are an important component of many organs and tissues, such as skin, lungs, arteries, ligaments, intervertebral discs and cartilage Their function is to endow tissues with elastic recoil and resilience, to act as an important adhesion template for cells, and to regulate growth factor availability (1,2). Loss or remodeling of the elastic fiber texture occurs in many diseases. Degeneration and fragmentation of elastic fibers and aging are intimately related (3). Recently, the importance of elastin for the study of malignant tumor progression has been emphasized (4,5). Elastic tissue may be a significant reservoir of angiostatic molecules and soluble elastin as well as elastin peptides, that are inhibitors of the metastatic process in experimental tumor models (4). Elastic fibers are involved in the anatomic remodeling of chronic pulmonary diseases (6) and, especially, of diseases of the arterial wall (7, 8). The study of these phenomena is important for the understanding of the pathophysiologic basis of the diseases. Recently the role of elastic fibers in small diameter vascular graft design has been emphasized (2). The possibility to regenerate or engineer elastic fibres and tissues creates an important challenge, not only to understand the molecular basis of elastic-fibre biology (1,2), but also of its spatial arrangement and remodeling in the diseased tissues. Subtle changes of the complex elastic fiber network may be involved in the pathogenesis of diseases. Therefore a precise and objective histopathologic description is necessary.

  18. Marked longevity of human lung parenchymal elastic fibers deduced from prevalence of D-aspartate and nuclear weapons-related radiocarbon

    SciTech Connect

    Shapiro, S.D.; Endicott, S.K.; Province, M.A.; Pierce, J.A.; Campbell, E.J. )

    1991-05-01

    Normal structure and function of the lung parenchyma depend upon elastic fibers. Amorphous elastin is biochemically stable in vitro, and may provide a metabolically stable structural framework for the lung parenchyma. To test the metabolic stability of elastin in the normal human lung parenchyma, we have (a) estimated the time elapsed since the synthesis of the protein through measurement of aspartic acid racemization and (b) modeled the elastin turnover through measurement of the prevalence of nuclear weapons-related {sup 14}C. Elastin purified by a new technique from normal lung parenchyma was hydrolyzed; then the prevalences of D-aspartate and {sup 14}C were measured by gas chromatography and accelerator-mass spectrometry, respectively. D-aspartate increased linearly with age; Kasp (1.76 x 10{sup {minus} 3} yr{sup {minus} 1}) was similar to that previously found for extraordinarily stable human tissues, indicating that the age of lung parenchymal elastin corresponded with the age of the subject. Radiocarbon prevalence data also were consistent with extraordinary metabolic stability of elastin; the calculated mean carbon residence time in elastin was 74 yr (95% confidence limits, 40-174 yr). These results indicate that airspace enlargement characteristic of 'aging lung' is not associated with appreciable new synthesis of lung parenchymal elastin. The present study provides the first tissue-specific evaluation of turnover of an extracellular matrix component in humans and underscores the potential importance of elastin for maintenance of normal lung structure. Most importantly, the present work provides a foundation for strategies to directly evaluate extracellular matrix injury and repair in diseases of lung (especially pulmonary emphysema), vascular tissue, and skin.

  19. Recoil Separators for Nuclear Astrophysics

    NASA Astrophysics Data System (ADS)

    Blackmon, J. C.

    2004-10-01

    Hydrogen and helium capture reactions are important in many astrophysical environments. Measurements in inverse kinematics using recoil separators have demonstrated a particularly sensitive technique for studying low-yield capture reactions.(M. S. Smith, C. E. Rolfs, and C. A. Barnes, Nucl. Instrum. Meth. Phys. Res. A306) (1991) 233. This approach allows a low background rate to be achieved with a high detection efficiency (about 50%) for the particles of interest using a device with only modest acceptance. Recoil separators using a variety of ion-optic configurations have been installed at numerous accelerator facilities in the past decade and have been used to measure, for example, alpha capture reactions using stable beams(D. Rogalla et al.), Eur. Phys. J. 6 (1999) 471. and proton capture reactions using radioactive ion beams.(S. Bishop et al.), Phys. Rev. Lett. 90 (2003) 162501. Measurements in inverse kinematics are the only viable means for studying reactions on short-lived nuclei that are crucial for understanding stellar explosions, and a recoil separator optimized for the measurement of capture reactions with radioactive ion beams figures prominently into the design of the low energy experimental area at the Rare Isotope Accelerator (RIA). The operational requirements for such a device will be outlined, and recoil separator designs and characteristics will be presented.

  20. Measurement of Nuclear Recoils in the CDMS II Dark Matter Search

    NASA Astrophysics Data System (ADS)

    Fallows, Scott M.

    The Cryogenic Dark Matter Search (CDMS) experiment is designed to directly detect elastic scatters of weakly-interacting massive dark matter particles (WIMPs), on target nuclei in semiconductor crystals composed of Si and Ge. These scatters would occur very rarely, in an overwhelming background composed primarily of electron recoils from photons and electrons, as well as a smaller but non-negligible background of WIMP-like nuclear recoils from neutrons. The CDMS~II generation of detectors simultaneously measure ionization and athermal phonon signals from each scatter, allowing discrimination against virtually all electron recoils in the detector bulk. Pulse-shape timing analysis allows discrimination against nearly all remaining electron recoils taking place near detector surfaces. Along with carefully limited neutron backgrounds, this experimental program allowed for "background-free'' operation of CDMS~II at Soudan, with less than one background event expected in each WIMP-search analysis. As a result, exclusionary upper-limits on WIMP-nucleon interaction cross section were placed over a wide range of candidate WIMP masses, ruling out large new regions of parameter space. These results, like any others, are subject to a variety of systematic effects that may alter their final interpretations. A primary focus of this dissertation will be difficulties in precisely calibrating the energy scale for nuclear recoil events like those from WIMPs. Nuclear recoils have suppressed ionization signals relative to electron recoils of the same recoil energy, so the response of the detectors is calibrated differently for each recoil type. The overall normalization and linearity of the energy scale for electron recoils in CDMS~II detectors is clearly established by peaks of known gamma energy in the ionization spectrum of calibration data from a 133Ba source. This electron-equivalent keVee) energy scale enables calibration of the total phonon signal (keVt) by enforcing unity

  1. First measurement of the ionization yield of nuclear recoils in liquid argon

    SciTech Connect

    Joshi, T.; Sangiorgio, Samuele; Bernstein, A.; Foxe, Michael P.; Hagmann, Chris; Jovanovic, Igor; Kazkaz, K.; Mozin, Vladimir V.; Norman, E. B.; Pereverzev, S. V.; Rebassoo, Finn O.; Sorensen, Peter F.

    2014-05-01

    Liquid phase argon has long been used as a target medium for particle detection via scintillation light. Recently there has been considerable interest in direct detection of both hypothetical darkmatter particles and coherent elastic neutrino nucleus scattering. These as-yet unobserved neutral particle interactions are expected to result in a recoiling argon atom O(keV), generally referred to in the literature as a nuclear recoil. This prompts the question of the available electromagnetic signal in a liquid argon detector. In this Letter we report the first measurement of the ionization yield (Qy), detected electrons per unit energy, resulting from nuclear recoils in liquid argon, measured at 6.7 keV. This is also the lowest energy measurement of nuclear recoils in liquid argon.

  2. A telescope proton recoil spectrometer for fast neutron beam-lines

    NASA Astrophysics Data System (ADS)

    Cazzaniga, C.; Rebai, M.; Tardocchi, M.; Croci, G.; Nocente, M.; Ansell, S.; Frost, C. D.; Gorini, G.

    2015-07-01

    Fast neutron measurements were performed on the VESUVIO beam-line at the ISIS spallation source using a new telescope proton recoil spectrometer. Neutrons interact on a plastic target. Proton production is mainly due to elastic scattering on hydrogen nuclei and secondly due to interaction with carbon nuclei. Recoil protons are measured by a proton spectrometer, which uses in coincidence a 2.54 cm thick YAP scintillator and a 500μm thick silicon detector, measuring the full proton recoil energy and the partial deposited energy in transmission, respectively. Recoil proton spectroscopy measurements (up to Ep = 60MeV) have been interpreted by using Monte Carlo simulations of the beam-line. This instrument is of particular interest for the characterization of the ChipIr beam-line at ISIS, which was designed to feature an atmospheric-like neutron spectrum for the irradiation of micro-electronics.

  3. A recoil resilient lumen support, design, fabrication and mechanical evaluation

    NASA Astrophysics Data System (ADS)

    Mehdizadeh, Arash; Ali, Mohamed Sultan Mohamed; Takahata, Kenichi; Al-Sarawi, Said; Abbott, Derek

    2013-06-01

    Stents are artificial implants that provide scaffolding to a cavity inside the body. This paper presents a new luminal device for reducing the mechanical failure of stents due to recoil, which is one of the most important issues in stenting. This device, which we call a recoil-resilient ring (RRR), is utilized standalone or potentially integrated with existing stents to address the problem of recoil. The proposed structure aims to minimize the need for high-pressure overexpansion that can induce intra-luminal trauma and excess growth of vascular tissue causing later restenosis. The RRR is an overlapped open ring with asymmetrical sawtooth structures that are intermeshed. These teeth can slide on top of each other, while the ring is radially expanded, but interlock step-by-step so as to keep the final expanded state against compressional forces that normally cause recoil. The RRRs thus deliver balloon expandability and, when integrated with a stent, bring both radial rigidity and longitudinal flexibility to the stent. The design of the RRR is investigated through finite element analysis (FEA), and then the devices are fabricated using micro-electro-discharge machining of 200-µm-thick Nitinol sheet. The standalone RRR is balloon expandable in vitro by 5-7 Atm in pressure, which is well within the recommended in vivo pressure ranges for stenting procedures. FEA compression tests indicate 13× less reduction of the cross-sectional area of the RRR compared with a typical stainless steel stent. These results also show perfect elastic recovery of the RRR after removal of the pressure compared to the remaining plastic deformations of the stainless steel stent. On the other hand, experimental loading tests show that the fabricated RRRs have 2.8× radial stiffness compared to a two-column section of a commercial stent while exhibiting comparable elastic recovery. Furthermore, testing of in vitro expansion in a mock artery tube shows around 2.9% recoil, approximately 5-11

  4. Acute effects of inhaled isoproterenol on the mechanical characteristics of the lungs in normal man

    PubMed Central

    McFadden, E. R.; Newton-Howes, Jan; Pride, N. B.

    1970-01-01

    We investigated the effects of isoproterenol on the pulmonary mechanics of eight healthy male subjects. We measured the flow-volume, pressure-volume, resistance-volume, and pressure-flow relationships of the lungs of our subjects in addition to the forced expiratory volume (FEV1). The results of this study confirm earlier observations that isoproterenol produces a considerable decrease in airway resistance but only small changes in maximum expiratory flow. Measurements of static pressure-volume curves showed that isoproterenol caused a temporary decrease in the elastic recoil pressure of the lungs. In five men there were mean falls in recoil pressure of 4.1 cm H2O at 85% total lung capacity (TLC), 2.6 cm H2O at 75% TLC, and 1.5 cm H2O at 50% TLC. We postulate that the reason for the relatively small increments in maximum expiratory flow after isoproterenol is primarily that the effects of airway dilatation are in large part negated by the reduction in lung recoil pressure, which results in a fall in the maximum effective driving force for expiratory air flow, and secondly that there is an increase in the compliance of the flow-limiting airways. These studies emphasize that tests of maximum flow and of airway resistance should not be regarded as invariably interchangeable in the assessment of airway reactions or mild disease of the airways. PMID:5443178

  5. Implicit mechanistic role of the collagen, smooth muscle, and elastic tissue components in strengthening the air and blood capillaries of the avian lung

    PubMed Central

    Maina, John N; Jimoh, Sikiru A; Hosie, Margo

    2010-01-01

    To identify the forces that may exist in the parabronchus of the avian lung and that which may explain the reported strengths of the terminal respiratory units, the air capillaries and the blood capillaries, the arrangement of the parabronchial collagen fibers (CF) of the lung of the domestic fowl, Gallus gallus variant domesticus was investigated by discriminatory staining, selective alkali digestion, and vascular casting followed by alkali digestion. On the luminal circumference, the atrial and the infundibular CF are directly connected to the smooth muscle fibers and the elastic tissue fibers. The CF in this part of the parabronchus form the internal column (the axial scaffold), whereas the CF in the interparabronchial septa and those associated with the walls of the interparabronchial blood vessels form the external, i.e. the peripheral, parabronchial CF scaffold. Thin CF penetrate the exchange tissue directly from the interparabronchial septa and indirectly by accompanying the intraparabronchial blood vessels. Forming a dense network that supports the air and blood capillaries, the CF weave through the exchange tissue. The exchange tissue, specifically the air and blood capillaries, is effectively suspended between CF pillars by an intricate system of thin CF, elastic and smooth muscle fibers. The CF course through the basement membranes of the walls of the blood and air capillaries. Based on the architecture of the smooth muscle fibers, the CF, the elastic muscle fibers, and structures like the interparabronchial septa and their associated blood vessels, it is envisaged that dynamic tensional, resistive, and compressive forces exist in the parabronchus, forming a tensegrity (tension integrity) system that gives the lung rigidity while strengthening the air and blood capillaries. PMID:20819116

  6. Implicit mechanistic role of the collagen, smooth muscle, and elastic tissue components in strengthening the air and blood capillaries of the avian lung.

    PubMed

    Maina, John N; Jimoh, Sikiru A; Hosie, Margo

    2010-11-01

    To identify the forces that may exist in the parabronchus of the avian lung and that which may explain the reported strengths of the terminal respiratory units, the air capillaries and the blood capillaries, the arrangement of the parabronchial collagen fibers (CF) of the lung of the domestic fowl, Gallus gallus variant domesticus was investigated by discriminatory staining, selective alkali digestion, and vascular casting followed by alkali digestion. On the luminal circumference, the atrial and the infundibular CF are directly connected to the smooth muscle fibers and the elastic tissue fibers. The CF in this part of the parabronchus form the internal column (the axial scaffold), whereas the CF in the interparabronchial septa and those associated with the walls of the interparabronchial blood vessels form the external, i.e. the peripheral, parabronchial CF scaffold. Thin CF penetrate the exchange tissue directly from the interparabronchial septa and indirectly by accompanying the intraparabronchial blood vessels. Forming a dense network that supports the air and blood capillaries, the CF weave through the exchange tissue. The exchange tissue, specifically the air and blood capillaries, is effectively suspended between CF pillars by an intricate system of thin CF, elastic and smooth muscle fibers. The CF course through the basement membranes of the walls of the blood and air capillaries. Based on the architecture of the smooth muscle fibers, the CF, the elastic muscle fibers, and structures like the interparabronchial septa and their associated blood vessels, it is envisaged that dynamic tensional, resistive, and compressive forces exist in the parabronchus, forming a tensegrity (tension integrity) system that gives the lung rigidity while strengthening the air and blood capillaries. PMID:20819116

  7. Respiratory symptoms and lung function in oil mist-exposed workers

    SciTech Connect

    Jarvholm, B.; Bake, B.; Lavenius, B.; Thiringer, G.; Vokmann, R.

    1982-06-01

    The prevalence of respiratory symptoms was registered and ventilatory function was determined in 164 men exposed to oil mist. The average exposure time was 16.2 years. One hundred fifty-nine office workers served as controls. The exposed men reported more respiratory symptoms: 14% of the exposed nonsmokers v. 2% of the nonsmoking controls having cough at least three months a year. There were non significant differences between spirometric measurements and chest roentgenograms of the men exposed to oil mist and those of the office workers. The lung function of 25 nonsmoking exposed men was further examined with other lung function tests. The mean values for closing volume, slope of the alveolar plateau, total lung capacity, residual volume, elastic recoil at various lung volumes, and diffusion capacity did not differ significantly.

  8. Angular Momentum Ejection and Recoil*

    NASA Astrophysics Data System (ADS)

    Ohia, O.; Coppi, B.

    2009-11-01

    The spontaneous rotation phenomenon observed in axisymmetric magnetically confined plasmas has been explained by the ``accretion theory'' [1] that considers the plasma angular momentum as gained from its interaction with the magnetic field and the surrounding material wall. The ejection of angular momentum to the wall, and the consequent recoil are attributed to modes excited at the edge while the transport of the (recoil) angular momentum from the edge toward the center is attributed to a different kind of mode. The toroidal phase velocity of the edge mode, to which the sign of the ejected angular momentum is related, is considered to change its direction in the transition from the H-regime to the L-regime. For the latter case, edge modes with phase velocity in the direction of vdi are driven by the temperature gradient of a cold ion population at the edge and damped on the ``hot'' ion population. The ``balanced'' double interaction [2] of the mode with the two populations, corresponding to a condition of marginal stability, leads to ejection of hot ions and loss of angular momentum in the direction of vdi while the cold population acquires angular momentum in the opposite direction. In the H-regime resistive ballooning modes with phase velocities in the direction of vde are viewed as the best candidates for the excited edge modes. *Sponsored in part by the U.S. DOE. [1] B. Coppi, Nucl. Fusion 42, 1 (2002) [2] B. Coppi and F. Pegoraro, Nucl. Fusion 17, 969 (1977)

  9. A recoil separator for nuclear astrophysics SECAR

    NASA Astrophysics Data System (ADS)

    Berg, G. P. A.; Bardayan, D. W.; Blackmon, J. C.; Chipps, K. A.; Couder, M.; Greife, U.; Hager, U.; Montes, F.; Rehm, K. E.; Schatz, H.; Smith, M. S.; Wiescher, M.; Wrede, C.; Zeller, A.

    2016-06-01

    A recoil separator SECAR has been designed to study radiative capture reactions relevant for the astrophysical rp-process in inverse kinematics for the Facility for Rare Isotope Beams (FRIB). We describe the design, layout, and ion optics of the recoil separator and present the status of the project.

  10. An elastic second skin.

    PubMed

    Yu, Betty; Kang, Soo-Young; Akthakul, Ariya; Ramadurai, Nithin; Pilkenton, Morgan; Patel, Alpesh; Nashat, Amir; Anderson, Daniel G; Sakamoto, Fernanda H; Gilchrest, Barbara A; Anderson, R Rox; Langer, Robert

    2016-08-01

    We report the synthesis and application of an elastic, wearable crosslinked polymer layer (XPL) that mimics the properties of normal, youthful skin. XPL is made of a tunable polysiloxane-based material that can be engineered with specific elasticity, contractility, adhesion, tensile strength and occlusivity. XPL can be topically applied, rapidly curing at the skin interface without the need for heat- or light-mediated activation. In a pilot human study, we examined the performance of a prototype XPL that has a tensile modulus matching normal skin responses at low strain (<40%), and that withstands elongations exceeding 250%, elastically recoiling with minimal strain-energy loss on repeated deformation. The application of XPL to the herniated lower eyelid fat pads of 12 subjects resulted in an average 2-grade decrease in herniation appearance in a 5-point severity scale. The XPL platform may offer advanced solutions to compromised skin barrier function, pharmaceutical delivery and wound dressings. PMID:27159017

  11. An elastic second skin

    NASA Astrophysics Data System (ADS)

    Yu, Betty; Kang, Soo-Young; Akthakul, Ariya; Ramadurai, Nithin; Pilkenton, Morgan; Patel, Alpesh; Nashat, Amir; Anderson, Daniel G.; Sakamoto, Fernanda H.; Gilchrest, Barbara A.; Anderson, R. Rox; Langer, Robert

    2016-08-01

    We report the synthesis and application of an elastic, wearable crosslinked polymer layer (XPL) that mimics the properties of normal, youthful skin. XPL is made of a tunable polysiloxane-based material that can be engineered with specific elasticity, contractility, adhesion, tensile strength and occlusivity. XPL can be topically applied, rapidly curing at the skin interface without the need for heat- or light-mediated activation. In a pilot human study, we examined the performance of a prototype XPL that has a tensile modulus matching normal skin responses at low strain (<40%), and that withstands elongations exceeding 250%, elastically recoiling with minimal strain-energy loss on repeated deformation. The application of XPL to the herniated lower eyelid fat pads of 12 subjects resulted in an average 2-grade decrease in herniation appearance in a 5-point severity scale. The XPL platform may offer advanced solutions to compromised skin barrier function, pharmaceutical delivery and wound dressings.

  12. Pulmonary mechanics and diffusion after 'shock lung'.

    PubMed Central

    Yernault, J C; Englert, M; Sergysels, R; De Coster, A

    1975-01-01

    Pulmonary function studies performed in seven patients who had recovered from 'shock lung' showed a highly significant decrease of diffusing properties of the lung, a slight loss of lung recoil pressure, and a borderline increase of residual volume with normal vital capacity and total lung capacity. Pulmonary compliance was normal. The interpretation of these findings is discussed. PMID:1145529

  13. Gas powered fluid gun with recoil mitigation

    DOEpatents

    Grubelich, Mark C.; Yonas, Gerold

    2016-03-01

    A gas powered fluid gun for propelling a stream or slug of a fluid at high velocity toward a target. Recoil mitigation is provided that reduces or eliminates the associated recoil forces, with minimal or no backwash. By launching a quantity of water in the opposite direction, net momentum forces are reduced or eliminated. Examples of recoil mitigation devices include a cone for making a conical fluid sheet, a device forming multiple impinging streams of fluid, a cavitating venturi, one or more spinning vanes, or an annular tangential entry/exit.

  14. Gas powered fluid gun with recoil mitigation

    DOEpatents

    Grubelich, Mark C; Yonas, Gerold

    2013-11-12

    A gas powered fluid gun for propelling a stream or slug of a fluid at high velocity toward a target. Recoil mitigation is provided that reduces or eliminates the associated recoil forces, with minimal or no backwash. By launching a quantity of water in the opposite direction, net momentum forces are reduced or eliminated. Examples of recoil mitigation devices include a cone for making a conical fluid sheet, a device forming multiple impinging streams of fluid, a cavitating venturi, one or more spinning vanes, or an annular tangential entry/exit.

  15. Design and characterization of a neutron calibration facility for the study of sub-keV nuclear recoils

    NASA Astrophysics Data System (ADS)

    Barbeau, P. S.; Collar, J. I.; Whaley, P. M.

    2007-05-01

    We have designed and built a highly monochromatic 24 keV neutron beam at the Kansas State University Triga Mark-II reactor, as part of an experimental effort to demonstrate sensitivity in a large-mass detector to the ultra-low energy recoils expected from coherent neutrino-nucleus elastic scattering. The beam characteristics were chosen so as to mimic the soft recoil energies expected from reactor antineutrinos in a variety of targets, allowing to understand the response of dedicated detector technologies in this yet unexplored sub-keV recoil range. A full characterization of the beam properties (intensity, monochromaticity, contaminations, beam profile) is presented, together with first tests of the calibration facility using proton recoils in organic scintillator.

  16. Nucleon elastic form factors

    SciTech Connect

    D. Day

    2007-03-01

    The nucleon form factors are still the subject of active investigation even after an experimental effort spanning 50 years. This is because they are of critical importance to our understanding of the electromagnetic properties of nuclei and provide a unique testing ground for QCD motivated models of nucleon structure. Progress in polarized beams, polarized targets and recoil polarimetry have allowed an important and precise set of data to be collected over the last decade. I will review the experimental status of elastic electron scattering from the nucleon along with an outlook for future progress.

  17. Measurement of nuclear recoil quenching factors in CaWO 4

    NASA Astrophysics Data System (ADS)

    Jagemann, Th.; Feilitzsch, F. v.; Hagn, H.; Jochum, J.; Potzel, W.; Rau, W.; Stark, M.; Westphal, W.

    2006-11-01

    The CRESST experiment, aiming at the direct detection of WIMPs via nuclear recoils, is currently using scintillating CaWO4 crystals. The WIMP-nucleus cross section for elastic scattering as well as the scintillation efficiency differ considerably for recoils from Ca, W and O in these crystals. Therefore a discriminating detector calibration is essential in order to improve WIMP parameter claims. At the tandem accelerator of the Maier-Leibnitz-Laboratory (MLL) in Garching, Germany, a neutron scattering facility is operated for the determination of the individual quenching factors (QF) in the bulk of a CaWO4 crystal to better understand the detector response to neutron background and a possible WIMP signal. First measurements at room temperature reveal QF(O) = 7.8 ± 0.3% (recoil energy 1.0-2.2 MeV), QF(Ca) = 6.3 ± 1.6% (recoil energy 0.4-1 MeV), QF(W) < 3.0% (2σ, recoil energy 0.1 MeV).

  18. Entropy Production and the Pressure-Volume Curve of the Lung.

    PubMed

    Oliveira, Cláudio L N; Araújo, Ascânio D; Bates, Jason H T; Andrade, José S; Suki, Béla

    2016-01-01

    We investigate analytically the production of entropy during a breathing cycle in healthy and diseased lungs. First, we calculate entropy production in healthy lungs by applying the laws of thermodynamics to the well-known transpulmonary pressure-volume (P-V) curves of the lung under the assumption that lung tissue behaves as an entropic spring similar to rubber. The bulk modulus, B, of the lung is also derived from these calculations. Second, we extend this approach to elastic recoil disorders of the lung such as occur in pulmonary fibrosis and emphysema. These diseases are characterized by particular alterations in the P-V relationship. For example, in fibrotic lungs B increases monotonically with disease progression, while in emphysema the opposite occurs. These diseases can thus be mimicked simply by making appropriate adjustments to the parameters of the P-V curve. Using Clausius's formalism, we show that entropy production, ΔS, is related to the hysteresis area, ΔA, enclosed by the P-V curve during a breathing cycle, namely, ΔS=ΔA∕T, where T is the body temperature. Although ΔA is highly dependent on the disease, such formula applies to healthy as well as diseased lungs, regardless of the disease stage. Finally, we use an ansatz to predict analytically the entropy produced by the fibrotic and emphysematous lungs. PMID:26973540

  19. Entropy Production and the Pressure–Volume Curve of the Lung

    PubMed Central

    Oliveira, Cláudio L. N.; Araújo, Ascânio D.; Bates, Jason H. T.; Andrade, José S.; Suki, Béla

    2016-01-01

    We investigate analytically the production of entropy during a breathing cycle in healthy and diseased lungs. First, we calculate entropy production in healthy lungs by applying the laws of thermodynamics to the well-known transpulmonary pressure–volume (P–V) curves of the lung under the assumption that lung tissue behaves as an entropic spring similar to rubber. The bulk modulus, B, of the lung is also derived from these calculations. Second, we extend this approach to elastic recoil disorders of the lung such as occur in pulmonary fibrosis and emphysema. These diseases are characterized by particular alterations in the P–V relationship. For example, in fibrotic lungs B increases monotonically with disease progression, while in emphysema the opposite occurs. These diseases can thus be mimicked simply by making appropriate adjustments to the parameters of the P–V curve. Using Clausius's formalism, we show that entropy production, ΔS, is related to the hysteresis area, ΔA, enclosed by the P–V curve during a breathing cycle, namely, ΔS=ΔA∕T, where T is the body temperature. Although ΔA is highly dependent on the disease, such formula applies to healthy as well as diseased lungs, regardless of the disease stage. Finally, we use an ansatz to predict analytically the entropy produced by the fibrotic and emphysematous lungs. PMID:26973540

  20. Transport of Radioactive Material by Alpha Recoil

    SciTech Connect

    Icenhour, A.S.

    2005-05-19

    The movement of high-specific-activity radioactive particles (i.e., alpha recoil) has been observed and studied since the early 1900s. These studies have been motivated by concerns about containment of radioactivity and the protection of human health. Additionally, studies have investigated the potential advantage of alpha recoil to effect separations of various isotopes. This report provides a review of the observations and results of a number of the studies.

  1. Sub-barrier reactions measured using a recoil mass separator

    SciTech Connect

    Betts, R.R.

    1988-01-01

    Few data exist in the sub-barrier region for reaction channels other than fusion. In particular, our experimental knowledge of quasi-elastic transfer reactions is sparse, despite the belief that this particular channel may be dominant in determining some features of the sub-barrier fusion enhancement. Transfer reactions are governed primarily by the closet approach of the colliding nuclei which, at low energies, results in a strong backward peaking of the angular distribution in the center-of-mass frame. For situations where the projectile has a significant fraction of the target mass, as is so in most cases of interest, the backscattered projectile-like fragment has such low energy that the usual techniques of measurement and identification become invalid. Here, we report on a solution to this problem which allows a systematic study of many aspects of transfer reactions in the energy regime of interest. We exploit the fact that associated with the low-energy backscattered projectile-like fragment is a complementary target-like fragment which recoils to forward angles with a large fraction of the incident beam energy. These target-like fragments were detected and identified using the Daresbury Recoil Mass Separator thus allowing the measurement of quasi-elastic transfer over hitherto inaccessible energy range from the vicinity of the barrier to several tens of MeV below. The experiments described here used VYNi beams of energies ranging from 180 to 260 MeV provided by the Daresbury Laboratory Nuclear Structure Facility tandem accelerator. Data on sub-barrier transfer for targets of /sup 116,118,120,122,124/Sn and /sup 144,148,150,152,154/Sm were obtained. 16 refs., 10 figs., 2 tabs.

  2. Mechanisms, assessment and therapeutic implications of lung hyperinflation in COPD.

    PubMed

    Rossi, Andrea; Aisanov, Zaurbek; Avdeev, Sergey; Di Maria, Giuseppe; Donner, Claudio F; Izquierdo, José Luis; Roche, Nicolas; Similowski, Thomas; Watz, Henrik; Worth, Heinrich; Miravitlles, Marc

    2015-07-01

    The main complaint of patients with chronic obstructive pulmonary disease (COPD) is shortness of breath with exercise, that is usually progressive. The principal mechanism that explains this symptom is the development of lung hyperinflation (LH) which is defined by an increase of functional residual capacity (FRC) above predicted values. Patients with COPD may develop static LH (sLH) because of destruction of pulmonary parenchyma and loss of elastic recoil. In addition, dynamic LH (dLH) develops when patients with COPD breathe in before achieving a full exhalation and, as a consequence, air is trapped within the lungs with each further breath. Dynamic LH may also occur at rest but it becomes clinically relevant during exercise and exacerbation. Lung hyperinflation may have an impact beyond the lungs and the effects of LH on cardiovascular function have been extensively analysed. The importance of LH makes its identification and measurement crucial. The demonstration of LH in COPD leads to the adoption of strategies to minimise its impact on the daily activities of patients. Several strategies reduce the impact of LH; the use of long-acting bronchodilators has been shown to reduce LH and improve exercise capacity. Non pharmacologic interventions have also been demonstrated to be useful. This article describes the pathophysiology of LH, its impact on the lungs and beyond and reviews the strategies that improve LH in COPD. PMID:25892293

  3. Sound production by a recoiling system in the pempheridae and terapontidae.

    PubMed

    Parmentier, Eric; Fine, Michael L; Mok, Hin-Kiu

    2016-06-01

    Sound-producing mechanisms in fishes are extraordinarily diversified. We report here original mechanisms of three species from two families: the pempherid Pempheris oualensis, and the terapontids Terapon jarbua and Pelates quadrilineatus. All sonic mechanisms are built on the same structures. The rostral part of the swimbladder is connected to a pair of large sonic muscles from the head whereas the posterior part is fused with bony widenings of vertebral bodies. Two bladder regions are separated by a stretchable fenestra that allows forward extension of the anterior bladder during muscle contraction. A recoiling apparatus runs between the inner face of the anterior swimbladder and a vertebral body expansion. The elastic nature of the recoiling apparatus supports its role in helping the swimbladder to recover its initial position during sonic muscle relaxation. This system should aid fast contraction (between 100 and 250Hz) of sonic muscles. There are many differences between species in terms of the swimbladder and its attachments to the vertebral column, muscle origins, and morphology of the recoiling apparatus. The recoiling apparatus found in the phylogenetically-related families (Glaucosomatidae, Pempheridae, Terapontidae) could indicate a new character within the Percomorpharia. J. Morphol. 277:717-724, 2016. © 2016 Wiley Periodicals, Inc. PMID:27021214

  4. Measurement of Nuclear Recoils in the CDMS II Dark Matter Search

    SciTech Connect

    Fallows, Scott Mathew

    2014-12-01

    The Cryogenic Dark Matter Search (CDMS) experiment is designed to directly detect elastic scatters of weakly-interacting massive dark matter particles (WIMPs), on target nuclei in semiconductor crystals composed of Si and Ge. These scatters would occur very rarely, in an overwhelming background composed primarily of electron recoils from photons and electrons, as well as a smaller but non-negligible background of WIMP-like nuclear recoils from neutrons. The CDMS II generation of detectors simultaneously measure ionization and athermal phonon signals from each scatter, allowing discrimination against virtually all electron recoils in the detector bulk. Pulse-shape timing analysis allows discrimination against nearly all remaining electron recoils taking place near detector surfaces. Along with carefully limited neutron backgrounds, this experimental program allowed for \\background- free" operation of CDMS II at Soudan, with less than one background event expected in each WIMP-search analysis. As a result, exclusionary upper-limits on WIMP-nucleon interaction cross section were placed over a wide range of candidate WIMP masses, ruling out large new regions of parameter space.

  5. Proton recoil scintillator neutron rem meter

    DOEpatents

    Olsher, Richard H.; Seagraves, David T.

    2003-01-01

    A neutron rem meter utilizing proton recoil and thermal neutron scintillators to provide neutron detection and dose measurement. In using both fast scintillators and a thermal neutron scintillator the meter provides a wide range of sensitivity, uniform directional response, and uniform dose response. The scintillators output light to a photomultiplier tube that produces an electrical signal to an external neutron counter.

  6. Role of fetal breathing movements in control of fetal lung distension.

    PubMed

    Miller, A A; Hooper, S B; Harding, R

    1993-12-01

    Our aim was to determine the role of fetal breathing movements (FBM) in the maintenance of fetal lung liquid volume. Experiments were performed in 14 chronically catheterized fetal sheep. FBM were selectively abolished for 48 h by the infusion of tetrodotoxin (TTX) onto the phrenic nerves of five fetuses. Lung liquid volumes and secretion rates were measured before each treatment, 46-48 h after the start of the TTX infusion, and 22-24 h after the end of the infusion. Blockade of the phrenic nerves reduced fetal lung liquid volumes from 27.6 +/- 1.9 to 21.8 +/- 2.6 ml/kg and increased lung liquid secretion rates from 3.8 +/- 0.6 to 6.2 +/- 1.1 ml.h-1.kg-1. Control experiments confirmed the lack of effect of TTX infused intravenously and saline infused intrapleurally on changes in fetal lung liquid volume and secretion rate. To measure the static relaxation volume of the fetal lung, in six fetuses we combined skeletal muscle paralysis with bypass of the upper airway for 48 h. This reduced fetal lung liquid volume from 39.1 +/- 3.1 to 23.0 +/- 2.5 ml/kg and increased lung liquid secretion rates from 4.1 +/- 0.7 to 5.8 +/- 0.9 ml.h-1.kg-1. This experiment demonstrates that the fetal lung is normally maintained at a level of expansion that is much greater than its static relaxation volume. We conclude that the volume of luminal liquid in the fetal lungs is dependent on the diaphragmatic contractions associated with FBM. Their effect is to resist the elastic recoil of the fetal lungs, thereby reducing the loss of liquid from the lungs via the trachea. PMID:8125894

  7. Clean recoil implantation of the 100Pd/Rh TDPAC probe using a solenoidal separator

    NASA Astrophysics Data System (ADS)

    Abiona, A. A.; Kemp, W. J.; Williams, E.; Timmers, H.

    2012-10-01

    The synthesis and recoil implantation of the 100Pd/Rh probe for time differential perturbed angular correlation (TDPAC) spectroscopy using the solenoidal reaction product separator SOLITAIRE has been demonstrated for the first time. The separator suppresses the co-implantation of the intense flux of elastically scattered projectile ions that can affect results obtained with the hyperfine interactions technique. Using three different fusion evaporation reactions, the solenoid field was optimised at 4.5 T to achieve a concentrated, circular focus of evaporation residue ions with a lateral FWHM of 20 mm. Employing the reaction 92Zr(12C,4n)100Pd several samples have been recoil-implanted with the 100Pd/Rh probe. Gamma-ray spectroscopy of a silver sample and a TDPAC measurement on zinc confirm that the new preparation technique is effective. The ratio function measured with TDPAC of an undoped germanium sample may indicate that palladium-defect pairs are absent when implanting with SOLITAIRE. However, a direct comparison with TDPAC results for germanium samples prepared with conventional recoil implantation, which does not suppress the flux of elastics, does not support this assertion.

  8. Ionization and scintillation of nuclear recoils in gaseous xenon

    NASA Astrophysics Data System (ADS)

    Renner, J.; Gehman, V. M.; Goldschmidt, A.; Matis, H. S.; Miller, T.; Nakajima, Y.; Nygren, D.; Oliveira, C. A. B.; Shuman, D.; Álvarez, V.; Borges, F. I. G.; Cárcel, S.; Castel, J.; Cebrián, S.; Cervera, A.; Conde, C. A. N.; Dafni, T.; Dias, T. H. V. T.; Díaz, J.; Esteve, R.; Evtoukhovitch, P.; Fernandes, L. M. P.; Ferrario, P.; Ferreira, A. L.; Freitas, E. D. C.; Gil, A.; Gómez, H.; Gómez-Cadenas, J. J.; González-Díaz, D.; Gutiérrez, R. M.; Hauptman, J.; Hernando Morata, J. A.; Herrera, D. C.; Iguaz, F. J.; Irastorza, I. G.; Jinete, M. A.; Labarga, L.; Laing, A.; Liubarsky, I.; Lopes, J. A. M.; Lorca, D.; Losada, M.; Luzón, G.; Marí, A.; Martín-Albo, J.; Martínez, A.; Moiseenko, A.; Monrabal, F.; Monserrate, M.; Monteiro, C. M. B.; Mora, F. J.; Moutinho, L. M.; Muñoz Vidal, J.; Natal da Luz, H.; Navarro, G.; Nebot-Guinot, M.; Palma, R.; Pérez, J.; Pérez Aparicio, J. L.; Ripoll, L.; Rodríguez, A.; Rodríguez, J.; Santos, F. P.; dos Santos, J. M. F.; Seguí, L.; Serra, L.; Simón, A.; Sofka, C.; Sorel, M.; Toledo, J. F.; Tomás, A.; Torrent, J.; Tsamalaidze, Z.; Veloso, J. F. C. A.; Villar, J. A.; Webb, R. C.; White, J.; Yahlali, N.

    2015-09-01

    Ionization and scintillation produced by nuclear recoils in gaseous xenon at approximately 14 bar have been simultaneously observed in an electroluminescent time projection chamber. Neutrons from radioisotope α-Be neutron sources were used to induce xenon nuclear recoils, and the observed recoil spectra were compared to a detailed Monte Carlo employing estimated ionization and scintillation yields for nuclear recoils. The ability to discriminate between electronic and nuclear recoils using the ratio of ionization to primary scintillation is demonstrated. These results encourage further investigation on the use of xenon in the gas phase as a detector medium in dark matter direct detection experiments.

  9. Recoil Based Fuel Breeding Fuel Structure

    SciTech Connect

    Popa-Simil, Liviu

    2008-07-01

    Nuclear transmutation reactions are based on the absorption of a smaller particle as neutron, proton, deuteron, alpha, etc. The resulting compound nucleus gets out of its initial lattice mainly by taking the recoil, also with help from its sudden change in chemical properties. The recoil implantation is used in correlation with thin and ultra thin materials mainly for producing radiopharmaceuticals and ultra-thin layer radioactive tracers. In nuclear reactors, the use of nano-particulate pellets could facilitate the recoil implantation for breeding, transmutation and partitioning purposes. Using enriched {sup 238}U or {sup 232}Th leads to {sup 239}Pu and {sup 233}U production while using other actinides as {sup 240}Pu, {sup 241}Am etc. leads to actinide burning. When such a lattice is immersed into a radiation resistant fluid (water, methanol, etc.), the recoiled product is transferred into the flowing fluid and removed from the hot area using a concentrator/purifier, preventing the occurrence of secondary transmutation reactions. The simulation of nuclear collision and energy transfer shows that the impacted nucleus recoils in the interstitial space creating a defect or lives small lattices. The defect diffuses, and if no recombination occurs it stops at the lattices boundaries. The nano-grains are coated in thin layer to get a hydrophilic shell to be washed by the collection liquid the particle is immersed in. The efficiency of collection depends on particle magnitude and nuclear reaction channel parameters. For {sup 239}Pu the direct recoil extraction rate is about 70% for {sup 238}UO{sub 2} grains of 5 nm diameters and is brought up to 95% by diffusion due to {sup 239}Neptunium incompatibility with Uranium dioxide lattice. Particles of 5 nm are hard to produce so a structure using particles of 100 nm have been tested. The particles were obtained by plasma sputtering in oxygen atmosphere. A novel effect as nano-cluster radiation damage robustness and cluster

  10. Cavity cooling below the recoil limit.

    PubMed

    Wolke, Matthias; Klinner, Julian; Keßler, Hans; Hemmerich, Andreas

    2012-07-01

    Conventional laser cooling relies on repeated electronic excitations by near-resonant light, which constrains its area of application to a selected number of atomic species prepared at moderate particle densities. Optical cavities with sufficiently large Purcell factors allow for laser cooling schemes, avoiding these limitations. Here, we report on an atom-cavity system, combining a Purcell factor above 40 with a cavity bandwidth below the recoil frequency associated with the kinetic energy transfer in a single photon scattering event. This lets us access a yet-unexplored regime of atom-cavity interactions, in which the atomic motion can be manipulated by targeted dissipation with sub-recoil resolution. We demonstrate cavity-induced heating of a Bose-Einstein condensate and subsequent cooling at particle densities and temperatures incompatible with conventional laser cooling. PMID:22767925

  11. Recoil polarization measurements of the proton electromagnetic form factor ratio at high momentum transfer

    SciTech Connect

    Andrew Puckett

    2009-12-01

    Electromagnetic form factors are fundamental properties of the nucleon that describe the effect of its internal quark structure on the cross section and spin observables in elastic lepton-nucleon scattering. Double-polarization experiments have become the preferred technique to measure the proton and neutron electric form factors at high momentum transfers. The recently completed GEp-III experiment at the Thomas Jefferson National Accelerator Facility used the recoil polarization method to extend the knowledge of the proton electromagnetic form factor ratio GpE/GpM to Q2 = 8.5 GeV2. In this paper we present the preliminary results of the experiment.

  12. Thermal recoil force, telemetry, and the Pioneer anomaly

    SciTech Connect

    Toth, Viktor T.; Turyshev, Slava G.

    2009-02-15

    Precision navigation of spacecraft requires accurate knowledge of small forces, including the recoil force due to anisotropies of thermal radiation emitted by spacecraft systems. We develop a formalism to derive the thermal recoil force from the basic principles of radiative heat exchange and energy-momentum conservation. The thermal power emitted by the spacecraft can be computed from engineering data obtained from flight telemetry, which yields a practical approach to incorporate the thermal recoil force into precision spacecraft navigation. Alternatively, orbit determination can be used to estimate the contribution of the thermal recoil force. We apply this approach to the Pioneer anomaly using a simulated Pioneer 10 Doppler data set.

  13. Recombination in liquid xenon for low-energy recoils

    NASA Astrophysics Data System (ADS)

    Wang, Lu; Mei, Dongming; Cubed Collaboration

    2014-09-01

    Detector response to low-energy recoils in sub-keV region is critical to detection of low-mass dark matter particles-WIMPS (Weakly interacting massive particles). The role of electron-ion recombination is important to the interpretation of the relation between ionization yield and scintillation yield, which are in general anti-correlated. Recent experimental results show that ionization yield increases down to keV range. This phenomenon contradicts general understanding for low energy recoils in the keV range in which direct excitation dominates. The explanation is that recombination becomes much less efficient when the track length is smaller than the thermalization distance of electrons. However, recombination rate is also proportional to ionization density, which is very high for keV recoils. To understand how recombination rate behaves for keV recoils, we calculated both initial recombination rate and volume recombination rate for keV recoils in liquid xenon. In this paper, we show the results of the calculated recombination rate as a function of recoil energy for both electronic recoils and nuclear recoils. Detector response to low-energy recoils in sub-keV region is critical to detection of low-mass dark matter particles-WIMPS (Weakly interacting massive particles). The role of electron-ion recombination is important to the interpretation of the relation between ionization yield and scintillation yield, which are in general anti-correlated. Recent experimental results show that ionization yield increases down to keV range. This phenomenon contradicts general understanding for low energy recoils in the keV range in which direct excitation dominates. The explanation is that recombination becomes much less efficient when the track length is smaller than the thermalization distance of electrons. However, recombination rate is also proportional to ionization density, which is very high for keV recoils. To understand how recombination rate behaves for keV recoils

  14. Neutron star recoils from anisotropic supernovae.

    NASA Astrophysics Data System (ADS)

    Janka, H.-T.; Mueller, E.

    1994-10-01

    Refering to recent hydrodynamical computations (Herant et al. 1992; Janka & Mueller 1993a) it is argued that neutron star kicks up to a few hundred km/s might be caused by a turbulent overturn of the matter between proto-neutron star and supernova shock during the early phase of the supernova explosion. These recoil speeds ("kick velocities") may be of the right size to explain the measured proper motions of most pulsars and do not require the presence of magnetic fields in the star. It is also possible that anisotropic neutrino emission associated with convective processes in the surface layers of the nascent neutron star (Burrows & Fryxell 1992; Janka & Mueller 1993b; Mueller 1993) provides an acceleration mechanism (Woosley 1987), although our estimates indicate that the maximum attainable velocities are around 200km/s. Yet, it turns out to be very unlikely that the considered stochastic asymmetries of supernova explosions are able to produce large enough recoils to account for pulsar velocities in excess of about 500km/s, which can be found in the samples of Harrison et al. (1993) and Taylor et al. (1993). It is concluded that other acceleration mechanisms have to be devised to explain the fast motion of PSR 2224+65 (transverse speed >=800km/s Cordes et al. 1993) and the high-velocities deduced from associations between supernova remnants and nearby young pulsars (e.g., Frail & Kulkarni 1991; Stewart et al. 1993; Caraveo 1993).

  15. Nuclear astrophysics studies by recoil mass separators.

    NASA Astrophysics Data System (ADS)

    Gialanella, L.; Brand, K.; Campajola, L.; D'Onofrio, A.; Greife, U.; Morone, M. C.; Oliviero, G.; Ordine, A.; Roca, V.; Rolfs, C.; Romano, M.; Romoli, M.; Schmidt, S.; Schulte, W. H.; Strieder, F.; Terrasi, F.; Trautvetter, H. P.; Zahnow, D.

    1997-11-01

    It has been recently demonstrated that an accelerator mass spectrometry (AMS) system, used as a recoil separator in conjunction with a windowless gas target, can yield the high suppression factor needed to dispersively analyze radiative capture residues, with the aim of measuring cross sections in the sub-microbarn range. An experiment is underway utilizing a radioactive 7Be beam for the measurement of the cross section of the astrophysically important reaction 7Be(p, γ)8B at a center of mass energy ECM = 1 MeV. Preliminary results of this experiment are presented. The extension of the method to another reaction playing a key role in stellar evolution, i.e. 12C(α, γ)16O, requires an improvement of the angle- and momentum-acceptance of the recoil separator, the use of a jet gas target and of a specially designed low-threshold detector. The solutions proposed by a joint Italian-German project are discussed.

  16. Smoking and intermediate alpha1-antitrypsin deficiency and lung function in middle-aged men.

    PubMed Central

    Larsson, C; Eriksson, S; Dirksen, H

    1977-01-01

    Lung function was evaluated in a representative population sample of 50-year-0ld men living in one Swedish city. Twenty-four smoking and 15 non-smoking men heterozygous for alpha1-antitrypsin deficiency--that is, with the protease-inhibitor (Pi1 phenotype MZ--were carefully matched for weight and smoking habit with Pi M controls. The pulmonary function of non-smoking Pi MZ subjects did not differ from that of non-smoking Pi M controls. In contrast, smoking heterozygotes showed a significant loss of elastic recoil, enlarged residual volumes, and increased closing capacity but no signs of obstructive ventilatory impairment. Most smoking Pi MZ individuals reported mild exertional dyspnoea. PMID:303135

  17. A gun recoil system employing a magnetorheological fluid damper

    NASA Astrophysics Data System (ADS)

    Li, Z. C.; Wang, J.

    2012-10-01

    This research aims to design and control a full scale gun recoil buffering system which works under real firing impact loading conditions. A conventional gun recoil absorber is replaced with a controllable magnetorheological (MR) fluid damper. Through dynamic analysis of the gun recoil system, a theoretical model for optimal design and control of the MR fluid damper for impact loadings is derived. The optimal displacement, velocity and optimal design rules are obtained. By applying the optimal design theory to protect against impact loadings, an MR fluid damper for a full scale gun recoil system is designed and manufactured. An experimental study is carried out on a firing test rig which consists of a 30 mm caliber, multi-action automatic gun with an MR damper mounted to the fixed base through a sliding guide. Experimental buffering results under passive control and optimal control are obtained. By comparison, optimal control is better than passive control, because it produces smaller variation in the recoil force while achieving less displacement of the recoil body. The optimal control strategy presented in this paper is open-loop with no feedback system needed. This means that the control process is sensor-free. This is a great benefit for a buffering system under impact loading, especially for a gun recoil system which usually works in a harsh environment.

  18. Difference between a Photon's Momentum and an Atom's Recoil

    SciTech Connect

    Gibble, Kurt

    2006-08-18

    When an atom absorbs a photon from a laser beam that is not an infinite plane wave, the atom's recoil is less than ({Dirac_h}/2{pi})k in the propagation direction. We show that the recoils in the transverse directions produce a lensing of the atomic wave functions, which leads to a frequency shift that is not discrete but varies linearly with the field amplitude and strongly depends on the atomic state detection. The same lensing effect is also important for microwave atomic clocks. The frequency shifts are of the order of the naive recoil shift for the transverse wave vector of the photons.

  19. Exerpts from the history of alpha recoils.

    PubMed

    Samuelsson, Christer

    2011-05-01

    Any confined air volume holding radon ((222)Rn) gas bears a memory of past radon concentrations due to (210)Pb (T(1/2) = 22 y) and its progenies entrapped in all solid objects in the volume. The efforts of quantifying past radon exposures by means of the left-behind long-lived radon progenies started in 1987 with this author's unsuccessful trials of removing (214)Po from radon exposed glass objects. In this contribution the history and different techniques of assessing radon exposure to man in retrospect will be overviewed. The main focus will be on the implantation of alpha recoils into glass surfaces, but also potential traps in radon dwellings will be discussed. It is concluded that for a successful retrospective application, three crucial imperatives must be met, i.e. firstly, the object must persistently store a certain fraction of the created (210)Pb atoms, secondly, be resistant over decades towards disturbances from the outside and thirdly, all (210)Pb atoms analysed must originate from airborne radon only. For large-scale radon epidemiological studies, non-destructive and inexpensive measurement techniques are essential. Large-scale studies cannot be based on objects rarely found in dwellings or not available for measurements. PMID:21306801

  20. Scintillation Efficiency of Liquid Xenon for Low Energy Nuclear Recoils

    NASA Astrophysics Data System (ADS)

    Wongjirad, Taritree; Ni, Kaixuan; Manzur, Angel; Kastens, Louis; McKinsey, Daniel

    2008-04-01

    In early 2006, the XENON and ZEPLIN collaborations announced highly stringent upper limits on the WIMP-nucleon cross-section. However, the dominant systematic uncertainty in these limits is due to the uncertainty in the nuclear recoil scintillation efficiency (NRSE) for liquid xenon. The NRSE is defined as the amount of scintillation produced by nuclear recoils, divided by the amount of scintillation produced by electron recoils, per unit energy. Though the NRSE has been measured by several groups, its value at the low energies most important for the liquid xenon WIMP searches has a large uncertainty. Furthermore, the NRSE may vary with the strength of the electric field in the liquid xenon. In an attempt to reduce these uncertainties, we have measured the NRSE down to 5 keV nuclear recoil energy for various electric fields.

  1. RECOILING SUPERMASSIVE BLACK HOLES IN SPIN-FLIP RADIO GALAXIES

    SciTech Connect

    Liu, F. K.; Wang Dong; Chen Xian

    2012-02-20

    Numerical relativity simulations predict that coalescence of supermassive black hole (SMBH) binaries leads not only to a spin flip but also to a recoiling of the merger remnant SMBHs. In the literature, X-shaped radio sources are popularly suggested to be candidates for SMBH mergers with spin flip of jet-ejecting SMBHs. Here we investigate the spectral and spatial observational signatures of the recoiling SMBHs in radio sources undergoing black hole spin flip. Our results show that SMBHs in most spin-flip radio sources have mass ratio q {approx}> 0.3 with a minimum possible value q{sub min} {approx_equal} 0.05. For major mergers, the remnant SMBHs can get a kick velocity as high as 2100 km s{sup -1} in the direction within an angle {approx}< 40 Degree-Sign relative to the spin axes of remnant SMBHs, implying that recoiling quasars are biased to be with high Doppler-shifted broad emission lines while recoiling radio galaxies are biased to large apparent spatial off-center displacements. We also calculate the distribution functions of line-of-sight velocity and apparent spatial off-center displacements for spin-flip radio sources with different apparent jet reorientation angles. Our results show that the larger the apparent jet reorientation angle is, the larger the Doppler-shifting recoiling velocity and apparent spatial off-center displacement will be. We investigate the effects of recoiling velocity on the dust torus in spin-flip radio sources and suggest that recoiling of SMBHs would lead to 'dust-poor' active galactic nuclei. Finally, we collect a sample of 19 X-shaped radio objects and for each object give the probability of detecting the predicted signatures of recoiling SMBH.

  2. Recoil splitting of x-ray-induced optical fluorescence

    SciTech Connect

    Gavrilyuk, S.; Aagren, H.; Gel'mukhanov, F.; Sun, Y.-P.; Levin, S.

    2010-03-15

    We show that the anisotropy of the recoil velocity distribution of x-ray-ionized atoms or molecules leads to observable splittings in subsequent optical fluorescence or absorption when the polarization vector of the x rays is parallel to the momentum of the fluorescent photons. The order of the magnitude of the recoil-induced splitting is about 10 {mu}eV, which can be observed using Fourier or laser-absorption spectroscopic techniques.

  3. Precision measurement of quenching factors for low-energy nuclear recoils at TUNL

    NASA Astrophysics Data System (ADS)

    Rich, Grayson; Barbeau, Phil; Howell, Calvin; Karwowski, Hugon

    2014-03-01

    With detector technologies becoming increasingly sensitive to exotic events, a thorough understanding of signal yield as a function of deposited energy is required for appropriate interpretation of results from cutting edge detector systems. Elastic neutron scattering is a probe which has been used to mimic the nuclear recoils which may be produced in detection media by light-WIMP interactions or coherent neutrino-nucleus scattering (CNS). We have built at the Triangle Universities Nuclear Laboratory (TUNL) a facility which produces pulsed, collimated, low-energy, quasi-monoenergetic neutron beams using the 7Li(p,n) reaction, resulting in fluxes of ~ 1 neutrons / (s . cm2) at ~90 cm from the neutron-production target. The first precision results from this facility are reported for ultra-low-energy recoils in NaI(Tl) and CsI(Na) and future plans are outlined, including measurements on candidate materials for a CNS detector that can potentially be fielded at the Spallation Neutron Source of Oak Ridge National Laboratory as a part the Coherent Scatter Initiative (CSI). We discuss the implications of new, precise measurements of quenching factors on neutrino detectors and on current- and next-generation light-WIMP searches, particularly the DAMA experiment.

  4. Recoil-α-fission and recoil-α-α-fission events observed in the reaction 48Ca + 243Am

    NASA Astrophysics Data System (ADS)

    Forsberg, U.; Rudolph, D.; Andersson, L.-L.; Di Nitto, A.; Düllmann, Ch. E.; Fahlander, C.; Gates, J. M.; Golubev, P.; Gregorich, K. E.; Gross, C. J.; Herzberg, R.-D.; Heßberger, F. P.; Khuyagbaatar, J.; Kratz, J. V.; Rykaczewski, K.; Sarmiento, L. G.; Schädel, M.; Yakushev, A.; Åberg, S.; Ackermann, D.; Block, M.; Brand, H.; Carlsson, B. G.; Cox, D.; Derkx, X.; Dobaczewski, J.; Eberhardt, K.; Even, J.; Gerl, J.; Jäger, E.; Kindler, B.; Krier, J.; Kojouharov, I.; Kurz, N.; Lommel, B.; Mistry, A.; Mokry, C.; Nazarewicz, W.; Nitsche, H.; Omtvedt, J. P.; Papadakis, P.; Ragnarsson, I.; Runke, J.; Schaffner, H.; Schausten, B.; Shi, Yue; Thörle-Pospiech, P.; Torres, T.; Traut, T.; Trautmann, N.; Türler, A.; Ward, A.; Ward, D. E.; Wiehl, N.

    2016-09-01

    Products of the fusion-evaporation reaction 48Ca + 243Am were studied with the TASISpec set-up at the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany. Amongst the detected thirty correlated α-decay chains associated with the production of element Z = 115, two recoil-α-fission and five recoil- α- α-fission events were observed. The latter five chains are similar to four such events reported from experiments performed at the Dubna gas-filled separator, and three such events reported from an experiment at the Berkeley gas-filled separator. The four chains observed at the Dubna gas-filled separator were assigned to start from the 2n-evaporation channel 289115 due to the fact that these recoil- α- α-fission events were observed only at low excitation energies. Contrary to this interpretation, we suggest that some of these recoil- α- α-fission decay chains, as well as some of the recoil- α- α-fission and recoil-α-fission decay chains reported from Berkeley and in this article, start from the 3n-evaporation channel 288115.

  5. Development of a gaseous proton-recoil detector for fission cross section measurements below 1 MeV neutron energy

    NASA Astrophysics Data System (ADS)

    Marini, P.; Mathieu, L.; Aïche, M.; Czajkowski, S.; Jurado, B.; Tsekhanovich, I.

    2016-03-01

    The elastic H(n,p) reaction is sometimes used to measure neutron flux, in order to produce high precision measurements. The use of this technique is not straightforward to use below incident neutron energy of 1 MeV, due to a high background in the detected proton spectrum. Experiments have been carried out at the AIFIRA facility to investigate such background and determine its origin and components. Based on these investigations, a gaseous proton-recoil detector has been designed, with a reduced low energy background.

  6. Elasticity theory

    NASA Astrophysics Data System (ADS)

    Moraru, Gheorghe; Mursa, Condrat

    2006-12-01

    In this book we present the basic concepts of the theory of elasticity: stress and deformation states (plane and three-dimensional) and generalized Hooke's law. We present a number of problems which have applications in strength analysis. The book includes a synthesis of the theory of elasticity and modern methods of applied mathematics. This book is designed for students, post graduate students and specialists in strength analysis. the book contains a number of appendixes which includes: elements of matrix-calculation, concepts of tensorial calculation, the Fourier transform, the notion of improper integrals,singular and hypersingular integrals, generalized functions, the Dirac Delta function

  7. Neutron spectrometer based on a proton telescope with electronic collimation of recoil protons

    NASA Astrophysics Data System (ADS)

    Milkov, V. M.; Panteleev, Ts. Ts.; Bogdzel, A.; Shvetsov, V. N.; Kutuzov, S.; Borzakov, S. B.; Sedyshev, P. V.

    2012-11-01

    A prototype of a neutron spectrometer based on a gas proportional counter with recoil-proton registration is created at the Frank Laboratory of Neutron Physics at the Joint Institute for Nuclear Research (FLNP JINR) in Dubna. The spectrometer is developed to measure the kinetic energy of protons scattered elastically at small angles that are produced by ( n, p) reaction in an environment containing hydrogen. The elaborated prototype consists of two cylindrical proportional counters used as cathodes. They are placed in a gas environment with a common centrally situated anode wire. Studies on the characteristics of the neutron spectrometer were conducted using 252Cf and 239Pu-Be radioisotope neutron sources. Measurements were made with monoenergetic neutrons produced by the 7Li( p, n)7Be reaction when a thin lithium target was bombarded with a proton beam from an EG-5 electrostatic accelerator, as well as with neutrons from the reaction D( d, n) 3He with a gas deuterium target.

  8. Neutron scattering facility for the calibration of the response to nuclear recoils

    NASA Astrophysics Data System (ADS)

    Jochum, J.; Chambon, B.; Drain, D.; von Feilitzsch, F.; Gascon, J.; Huber, M.; Jagemann, T.; de Jésus, M.; Lachenmaier, T.; Lanfranchi, J.-C.; Martineau, O.; Potzel, W.; Rüdig, A.; Schnagl, J.; Simon, E.; Stark, M.; Stern, M.; Wulandari, H.

    2002-02-01

    A possibility to search for elementary particles as dark matter candidates is to detect elastic scattering with cryogenic detectors. For the interpretation of the data one has to determine the detector response to nuclear recoils, the so-called quenching factors. They can differ for the heat-, for the scintillation- and for the ionization-signal and can be measured by scattering of neutrons. The CRESST- and the EDELWEISS-collaborations have set up a neutron scattering facility for cryogenic detectors at the tandem-accelerator of the Munich `Maier-Leibniz-Labor.' The scattering angle and the time-of-flight of the neutrons are measured by an array of liquid scintillator cells. The pulsed high energy (11 MeV) neutron beam is created by nuclear reaction of a 11B on a H2-gas target. The set-up and the results of first tests are presented. .

  9. Median recoil direction as a WIMP directional detection signal

    NASA Astrophysics Data System (ADS)

    Green, Anne M.; Morgan, Ben

    2010-03-01

    Direct detection experiments have reached the sensitivity to detect dark matter weakly interacting massive particles (WIMPs). Demonstrating that a putative signal is due to WIMPs, and not backgrounds, is a major challenge, however. The direction dependence of the WIMP scattering rate provides a potential WIMP “smoking gun.” If the WIMP distribution is predominantly smooth, the Galactic recoil distribution is peaked in the direction opposite to the direction of Solar motion. Previous studies have found that, for an ideal detector, of order 10 WIMP events would be sufficient to reject isotropy, and rule out an isotropic background. We examine how the median recoil direction could be used to confirm the WIMP origin of an anisotropic recoil signal. Specifically, we determine the number of events required to confirm the direction of solar motion as the median inverse recoil direction at 95% confidence. We find that for zero background 31 events are required, a factor of ˜2 more than are required to simply reject isotropy. We also investigate the effect of a nonzero isotropic background. As the background rate is increased the number of events required increases, initially fairly gradually and then more rapidly, once the signal becomes subdominant. We also discuss the effect of features in the speed distribution at large speeds, as found in recent high resolution simulations, on the median recoil direction.

  10. Stimulated Rayleigh resonances and recoil-induced effects

    SciTech Connect

    Courtois, J.Y.; Grynberg, G.

    1996-12-31

    The organization of this paper is as follows. We present in Section II the basic ideas about stimulated Rayleigh scattering by considering more particularly the situation where it arises from a relaxation process going on in the material system, and we describe a few experimental observations made in atomic and molecular physics. We then consider the case of nonstationary two-level atoms, and we derive the shape and characteristics of the recoil-induced resonances (Section III). In particular, we show that these resonances can be interpreted either as originating from a stimulated Rayleigh effect or as a stimulated Raman phenomena between atomic energy-momentum states having different momenta. Finally, to make a clear distinction between the physical phenomena that pertain directly to recoil-induced processes (i.e., that actually permit the measurement of the photon recoil) and those for which the introduction of the recoil constitutes a mere physical convenience, we review in Section IV some indisputable manifestations of the photon recoil in atomic and molecular physics. 92 refs., 22 figs.

  11. Median recoil direction as a WIMP directional detection signal

    SciTech Connect

    Green, Anne M.; Morgan, Ben

    2010-03-15

    Direct detection experiments have reached the sensitivity to detect dark matter weakly interacting massive particles (WIMPs). Demonstrating that a putative signal is due to WIMPs, and not backgrounds, is a major challenge, however. The direction dependence of the WIMP scattering rate provides a potential WIMP 'smoking gun'. If the WIMP distribution is predominantly smooth, the Galactic recoil distribution is peaked in the direction opposite to the direction of Solar motion. Previous studies have found that, for an ideal detector, of order 10 WIMP events would be sufficient to reject isotropy, and rule out an isotropic background. We examine how the median recoil direction could be used to confirm the WIMP origin of an anisotropic recoil signal. Specifically, we determine the number of events required to confirm the direction of solar motion as the median inverse recoil direction at 95% confidence. We find that for zero background 31 events are required, a factor of {approx}2 more than are required to simply reject isotropy. We also investigate the effect of a nonzero isotropic background. As the background rate is increased the number of events required increases, initially fairly gradually and then more rapidly, once the signal becomes subdominant. We also discuss the effect of features in the speed distribution at large speeds, as found in recent high resolution simulations, on the median recoil direction.

  12. Calculation of recoil implantation profiles using known range statistics

    NASA Technical Reports Server (NTRS)

    Fung, C. D.; Avila, R. E.

    1985-01-01

    A method has been developed to calculate the depth distribution of recoil atoms that result from ion implantation onto a substrate covered with a thin surface layer. The calculation includes first order recoils considering projected range straggles, and lateral straggles of recoils but neglecting lateral straggles of projectiles. Projectile range distributions at intermediate energies in the surface layer are deduced from look-up tables of known range statistics. A great saving of computing time and human effort is thus attained in comparison with existing procedures. The method is used to calculate recoil profiles of oxygen from implantation of arsenic through SiO2 and of nitrogen from implantation of phosphorus through Si3N4 films on silicon. The calculated recoil profiles are in good agreement with results obtained by other investigators using the Boltzmann transport equation and they also compare very well with available experimental results in the literature. The deviation between calculated and experimental results is discussed in relation to lateral straggles. From this discussion, a range of surface layer thickness for which the method applies is recommended.

  13. Nuclear Recoil Calibration of DarkSide-50

    NASA Astrophysics Data System (ADS)

    Edkins, Erin; DarkSide Collaboration

    2016-03-01

    DarkSide-50 dark matter experiment is a liquid argon time projection chamber (TPC) surrounded by a liquid scintillator active neutron veto, designed for the direct detection of Weakly Interacting Massive Particles (WIMPs). The success of such an experiment is dependent upon a detailed understanding of both the expected signal and backgrounds, achieved using radioactive calibration sources of known energies. Nuclear recoils provide a measurement of both the expected signal and the most dangerous background, as nuclear recoils from neutrons cannot be distinguished from a dark matter signal on an event-by-event basis in the TPC. In this talk, I will present the DS-50 calibration system, and analysis of the results of the calibration of DarkSide-50 to nuclear recoils using radioactive neutron sources. See also the DS-50 presentations by X. Xiang and G. Koh.

  14. Accounting for Recoil Effects in Geochronometers: A New Model Approach

    NASA Astrophysics Data System (ADS)

    Lee, V. E.; Huber, C.

    2012-12-01

    A number of geologically important chronometers are affected by, or owe their utility to, the "recoil effect". This effect describes the physical displacement of a nuclide due to energetic nuclear processes such as radioactive alpha decay (as in the case of various parent-daughter pairs in the uranium-series decay chains, and Sm-Nd), as well as neutron irradiation (in the case of the methodology for the 40Ar/39Ar dating method). The broad range of affected geochronometers means that the recoil effect can impact a wide range of dating method applications in the geosciences, including but not limited to: Earth surface processes, paleoclimate, volcanic processes, and cosmochemistry and planetary evolution. In particular, the recoil effect can have a notable impact on the use of fine grains (silt- and clay-sized particles) for geochronometric dating purposes. This is because recoil-induced loss of a nuclide from the surfaces of a grain can create an isotopically-depleted outer rind, and for small grains, this depleted rind can be volumetrically significant. When this recoil loss is measurable and occurs in a known time-dependent fashion, it can usefully serve as the basis for chronometers (such as the U-series comminution age method); in other cases recoil loss from fine particles creates an unwanted deviation from expected isotope values (such as for the Ar-Ar method). To improve both the accuracy and precision of ages inferred from geochronometric systems that involve the recoil of a key nuclide from small domains, it is necessary to quantify the magnitude of the recoil loss of that particular nuclide. It is also necessary to quantitatively describe the effect of geological processes that can alter the outer surface of grains, and hence the isotopically-depleted rind. Here we present a new mathematical and numerical model that includes two main features that enable enhanced accuracy and precision of ages determined from geochronometers. Since the surface area of the

  15. Recoil release of fission products from nuclear fuel

    NASA Astrophysics Data System (ADS)

    Wise, C.

    1985-10-01

    An analytical approximation is developed for calculating recoil release from nuclear fuel into gas filled interspaces. This expression is evaluated for a number of interspace geometries and shown to be generally accurate to within about 10% by comparison with numerical calculations. The results are applied to situations of physical interest and it is demonstrated that recoil can be important when modelling fission product release from low temperature CAGR pin failures. Furthermore, recoil can contribute significantly in experiments on low temperature fission product release, particularly where oxidation enhancement of this release is measured by exposing the fuel to CO 2. The calculations presented here are one way of allowing for this, other methods are suggested.

  16. Fission product release from nuclear fuel by recoil and knockout

    NASA Astrophysics Data System (ADS)

    Lewis, B. J.

    1987-03-01

    An analytical model has been developed to describe the fission product release from nuclear fuel arising from the surface-fission release mechanisms of recoil and knockout. Release expressions are evaluated and compared to the short-lived activity measurements from in-reactor experiments with intact operating fuel. Recoil is shown to be an important process for releasing fission products from free UO 2 surfaces into the fuel-to-sheath gap. The model is also applied to tramp uranium in a power reactor primary heat transport circuit where it is demonstrated that recoil is the dominant release mechanism for small particles of fuel which are deposited on in-core surfaces. A methodology is established whereby release from surface contamination can be distinguished from that of fuel pin failure.

  17. Physiological and Computed Tomographic Predictors of Outcome from Lung Volume Reduction Surgery

    PubMed Central

    Washko, George R.; Martinez, Fernando J.; Hoffman, Eric A.; Loring, Stephen H.; Estépar, Raúl San José; Diaz, Alejandro A.; Sciurba, Frank C.; Silverman, Edwin K.; Han, MeiLan K.; DeCamp, Malcolm; Reilly, John J.

    2010-01-01

    Rationale: Previous investigations have identified several potential predictors of outcomes from lung volume reduction surgery (LVRS). A concern regarding these studies has been their small sample size, which may limit generalizability. We therefore sought to examine radiographic and physiologic predictors of surgical outcomes in a large, multicenter clinical investigation, the National Emphysema Treatment Trial. Objectives: To identify objective radiographic and physiological indices of lung disease that have prognostic value in subjects with chronic obstructive pulmonary disease being evaluated for LVRS. Methods: A subset of the subjects undergoing LVRS in the National Emphysema Treatment Trial underwent preoperative high-resolution computed tomographic (CT) scanning of the chest and measures of static lung recoil at total lung capacity (SRtlc) and inspiratory resistance (Ri). The relationship between CT measures of emphysema, the ratio of upper to lower zone emphysema, CT measures of airway disease, SRtlc, Ri, the ratio of residual volume to total lung capacity (RV/TLC), and both 6-month postoperative changes in FEV1 and maximal exercise capacity were assessed. Measurements and Main Results: Physiological measures of lung elastic recoil and inspiratory resistance were not correlated with improvement in either the FEV1 (R = −0.03, P = 0.78 and R = –0.17, P = 0.16, respectively) or maximal exercise capacity (R = –0.02, P = 0.83 and R = 0.08, P = 0.53, respectively). The RV/TLC ratio and CT measures of emphysema and its upper to lower zone ratio were only weakly predictive of postoperative changes in both the FEV1 (R = 0.11, P = 0.01; R = 0.2, P < 0.0001; and R = 0.23, P < 0.0001, respectively) and maximal exercise capacity (R = 0.17, P = 0.0001; R = 0.15, P = 0.002; and R = 0.15, P = 0.002, respectively). CT assessments of airway disease were not predictive of change in FEV1 or exercise capacity in this cohort. Conclusions: The RV/TLC ratio and CT measures

  18. Ionic recoil energies in the Coulomb explosion of metal clusters

    NASA Astrophysics Data System (ADS)

    Teuber, S.; Döppner, T.; Fennel, T.; Tiggesbäumker, J.; Meiwes-Broer, K. H.

    The photoionization of metal clusters in intense femtosecond laser fields has been studied. In contrast to an experiment on atoms, the interaction in this case leads to a very efficient and high charging of the particle where tens of electrons per atom are ejected from the cluster. The recoil energy distribution of the atomic fragment ions was measured which in the case of lead clusters exceeds 180 keV. Enhanced charging efficiency which we observed earlier for specific pulse conditions is not reflected in the recoil energy spectra. Both the average and the maximum energies decrease with increasing laser pulse width. This is in good agreement with molecular dynamics calculations.

  19. Status and Prospects of the HERMES Recoil Detector

    SciTech Connect

    Mussgiller, Andreas

    2009-08-04

    Hard exclusive processes provide access to generalized parton distributions (GPDs), which extend our description of the nucleon structure beyond the standard parton distributions. The Deeply Virtual Compton Scattering (DVCS) process provides the theoretically cleanest access to the GPDs. For the final two years of data taking, a recoil detector was installed at HERMES for the purpose of improving the ability to measure hard-exclusive processes. In addition the recoil detector allows one to measure the individual background contributions which can be used to refine previously published results on DVCS. The progress of the ongoing data analysis is presented.

  20. Model independent radiative corrections in processes of polarized electron-nucleon elastic scattering

    SciTech Connect

    Igor Akushevich; Andrei Afanasev; Mykola Merenkov

    2001-12-01

    The explicit formulae for radiative correction (RC) calculation for elastic ep-scattering is presented. Two typical measurements of polarization observables such as beam-target asymmetry or recoil proton polarization, are considered. Possibilities to take into account realistic experimental acceptances are discussed. The Fortran code MASCARAD for providing the RC procedure is presented. Numerical analysis is done for kinematical conditions of TJNAF.

  1. Model independent radiative corrections in processes of polarized electron-nucleon elastic scattering

    NASA Astrophysics Data System (ADS)

    Afanasev, A.; Akushevich, I.; Merenkov, N.

    2001-12-01

    Explicit formulas for radiative correction (RC) calculations for elastic ep scattering are presented. Two typical measurements of polarization observables, such as beam-target asymmetry or recoil proton polarization, are considered. The possibilities of taking into account realistic experimental acceptances are discussed. The FORTRAN code MASCARAD for providing the RC procedure is presented. A numerical analysis is done for the kinematical conditions of CEBAF.

  2. QED Radiative Corrections to Asymmetries of Elastic ep-scattering in Hadronic Variables

    SciTech Connect

    Alexander Ilyichev; Andrei Afanasev; Igor Akushevich; Mykola Merenkov

    2001-08-16

    Compact analytical formulae for QED radiative corrections in the processes of elastic e-p scattering are obtained in the case when kinematic variables are reconstructed from the recoil proton momentum measured. Numerical analysis is presented under kinematic conditions of current experiments at JLab.

  3. Direct Measurement of Photon Recoil from a Levitated Nanoparticle

    NASA Astrophysics Data System (ADS)

    Jain, Vijay; Gieseler, Jan; Moritz, Clemens; Dellago, Christoph; Quidant, Romain; Novotny, Lukas

    2016-06-01

    The momentum transfer between a photon and an object defines a fundamental limit for the precision with which the object can be measured. If the object oscillates at a frequency Ω0 , this measurement backaction adds quanta ℏΩ0 to the oscillator's energy at a rate Γrecoil, a process called photon recoil heating, and sets bounds to coherence times in cavity optomechanical systems. Here, we use an optically levitated nanoparticle in ultrahigh vacuum to directly measure Γrecoil. By means of a phase-sensitive feedback scheme, we cool the harmonic motion of the nanoparticle from ambient to microkelvin temperatures and measure its reheating rate under the influence of the radiation field. The recoil heating rate is measured for different particle sizes and for different excitation powers, without the need for cavity optics or cryogenic environments. The measurements are in quantitative agreement with theoretical predictions and provide valuable guidance for the realization of quantum ground-state cooling protocols and the measurement of ultrasmall forces.

  4. Direct Measurement of Photon Recoil from a Levitated Nanoparticle.

    PubMed

    Jain, Vijay; Gieseler, Jan; Moritz, Clemens; Dellago, Christoph; Quidant, Romain; Novotny, Lukas

    2016-06-17

    The momentum transfer between a photon and an object defines a fundamental limit for the precision with which the object can be measured. If the object oscillates at a frequency Ω_{0}, this measurement backaction adds quanta ℏΩ_{0} to the oscillator's energy at a rate Γ_{recoil}, a process called photon recoil heating, and sets bounds to coherence times in cavity optomechanical systems. Here, we use an optically levitated nanoparticle in ultrahigh vacuum to directly measure Γ_{recoil}. By means of a phase-sensitive feedback scheme, we cool the harmonic motion of the nanoparticle from ambient to microkelvin temperatures and measure its reheating rate under the influence of the radiation field. The recoil heating rate is measured for different particle sizes and for different excitation powers, without the need for cavity optics or cryogenic environments. The measurements are in quantitative agreement with theoretical predictions and provide valuable guidance for the realization of quantum ground-state cooling protocols and the measurement of ultrasmall forces. PMID:27367388

  5. Isotopic disequilibrium of uranium: alpha-recoil damage and preferential solution effects

    SciTech Connect

    Fleischer, R.L.

    1980-02-29

    Preferential loss of uranium-234 relative to uranium-238 from rocks into solutions has long been attributed to recoiling alpha-emitting nuclei. Direct evidence has been obtained for two mechanisms, first, recoil ejection from grains, and now release by natural etching of alpha-recoil tracks. The observations have implications for radon emanation and for the storage of alpha-emitting radioactive waste.

  6. Tensor polarization in elastic electron-deuteron scattering in the momentum transfer range 3. 8[le][ital Q][le]4. 6 fm[sup [minus]1

    SciTech Connect

    Garcon, M.; Arvieux, J.; Beck, D.H.; Beise, E.J.; Boudard, A.; Cairns, E.B.; Cameron, J.M.; Dodson, G.W.; Dow, K.A.; Farkhondeh, M.; Fielding, H.W.; Flanz, J.B.; Goloskie, R.; Hoibraten, S.; Jourdan, J.; Kowalski, S.; Lapointe, C.; McDonald, W.J.; Nia, B.; Pham, L.D.; Redwine, R.P.; Rodning, N.L.; Roy, G.; Schulze, M.E.; Souder, P.A.; Soukup, J.; The, I.; Turchinetz, W.E.; Williamson, C.F.; Wilson, K.E.; Wood, S.A.; Ziegler, W. California Institute of Technology, Pasadena, California 91125 University of Illinois, Champaign, Illinois 61820 Indiana University Cyclotron Facility, Bloomington, Indiana 47405 Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 Service de Physique Nucleaire, Centre d'Etudes Nucleaires de Saclay, 91191 Gif-sur-Yvette Laboratoire National Saturne, 91191 Gif-sur-Yvette Syracuse University, Syracuse, New

    1994-05-01

    The tensor polarization of the recoil deuteron in elastic electron-deuteron scattering has been measured at the Bates Linear Accelerator Center at three values of four-momentum transfer [ital Q]=3.78, 4.22, and 4.62 fm[sup [minus]1], corresponding to incident electron energies of 653, 755, and 853 MeV. The scattered electrons and the recoil deuterons were detected in coincidence. The recoil deuterons were transported to a liquid hydrogen target to undergo a second scattering. The angular distribution of the [ital [rvec d

  7. Advances in biomimetic regeneration of elastic matrix structures

    PubMed Central

    Sivaraman, Balakrishnan; Bashur, Chris A.

    2012-01-01

    Elastin is a vital component of the extracellular matrix, providing soft connective tissues with the property of elastic recoil following deformation and regulating the cellular response via biomechanical transduction to maintain tissue homeostasis. The limited ability of most adult cells to synthesize elastin precursors and assemble them into mature crosslinked structures has hindered the development of functional tissue-engineered constructs that exhibit the structure and biomechanics of normal native elastic tissues in the body. In diseased tissues, the chronic overexpression of proteolytic enzymes can cause significant matrix degradation, to further limit the accumulation and quality (e.g., fiber formation) of newly deposited elastic matrix. This review provides an overview of the role and importance of elastin and elastic matrix in soft tissues, the challenges to elastic matrix generation in vitro and to regenerative elastic matrix repair in vivo, current biomolecular strategies to enhance elastin deposition and matrix assembly, and the need to concurrently inhibit proteolytic matrix disruption for improving the quantity and quality of elastogenesis. The review further presents biomaterial-based options using scaffolds and nanocarriers for spatio-temporal control over the presentation and release of these biomolecules, to enable biomimetic assembly of clinically relevant native elastic matrix-like superstructures. Finally, this review provides an overview of recent advances and prospects for the application of these strategies to regenerating tissue-type specific elastic matrix structures and superstructures. PMID:23355960

  8. A Study of Intrinsic Statistical Variation for Nuclear Recoils in Germanium Detector for Dark Matter Searches

    NASA Astrophysics Data System (ADS)

    Wei, Wenzhao; Wang, Lu; Mei, Dongming; Cubed Collaboration

    2015-10-01

    The intrinsic statistical variation in nuclear recoils is a critical part that cannot be ignored when calculating energy resolution of germanium detector in detecting WIMPs. Have a good theoretical understanding about the intrinsic statistical variation in nuclear recoils and develop a model for calculating this variation based on experimental data is of great importance in determining the width of nuclear recoil band, which is used to identify nuclear recoils events. Hence, we designed an experiment to study the intrinsic statistical variation in nuclear recoils with various gamma sources and AmBe neutron source. In addition, we developed a theoretical model to calculate the intrinsic statistical variation in nuclear recoils based on data from AmBe neutron source. In this work, we will present our data and theoretical calculation for nuclear recoils. This work is supported by NSF in part by the NSF PHY-0758120, DOE grant DE-FG02-10ER46709, and the State of South Dakota.

  9. Lung Transplant

    MedlinePlus

    ... the NHLBI on Twitter. What Is a Lung Transplant? A lung transplant is surgery to remove a person's diseased lung ... a healthy lung from a deceased donor. Lung transplants are used for people who are likely to ...

  10. Characterization of the CRESST detectors by neutron induced nuclear recoils

    NASA Astrophysics Data System (ADS)

    Coppi, C.; Ciemniak, C.; von Feilitzsch, F.; Gütlein, A.; Hagn, H.; Isaila, C.; Jochum, J.; Kimmerle, M.; Lanfranchi, J.-C.; Pfister, S.; Potzel, W.; Rau, W.; Roth, S.; Rottler, K.; Sailer, C.; Scholl, S.; Usherov, I.; Westphal, W.

    CRESST is an experiment for the direct detection of dark matter particles via nuclear recoils. The CRESST detectors, based on CaWO4 scintillating crystals, are able to discriminate γ and β background by simultaneously measuring the light and phonon signals produced by particle interactions. The discrimination of the background is possible because of the different light output (Quenching Factor, QF) for nuclear and electron recoils. In this article a measurement is shown, aimed at the determination of the QFs of the different nuclei (O, Ca, W) of the detector crystal at 40-60 mK using an 11 MeV neutron beam produced at the Maier-Leibnitz-Laboratorium in Garching (MLL).

  11. Recoiling supermassive black holes: a search in the nearby universe

    SciTech Connect

    Lena, D.; Robinson, A.; Axon, D. J.; Merritt, D.; Marconi, A.; Capetti, A.; Batcheldor, D.

    2014-11-10

    The coalescence of a binary black hole can be accompanied by a large gravitational recoil due to anisotropic emission of gravitational waves. A recoiling supermassive black hole (SBH) can subsequently undergo long-lived oscillations in the potential well of its host galaxy, suggesting that offset SBHs may be common in the cores of massive ellipticals. We have analyzed Hubble Space Telescope archival images of 14 nearby core ellipticals, finding evidence for small (≲ 10 pc) displacements between the active galactic nucleus (AGN; the location of the SBH) and the center of the galaxy (the mean photocenter) in 10 of them. Excluding objects that may be affected by large-scale isophotal asymmetries, we consider six galaxies to have detected displacements, including M87, where a displacement was previously reported by Batcheldor et al. In individual objects, these displacements can be attributed to residual gravitational recoil oscillations following a major or minor merger within the last few gigayears. For plausible merger rates, however, there is a high probability of larger displacements than those observed, if SBH coalescence took place in these galaxies. Remarkably, the AGN-photocenter displacements are approximately aligned with the radio source axis in four of the six galaxies with displacements, including three of the four having relatively powerful kiloparsec-scale jets. This suggests intrinsic asymmetries in radio jet power as a possible displacement mechanism, although approximate alignments are also expected for gravitational recoil. Orbital motion in SBH binaries and interactions with massive perturbers can produce the observed displacement amplitudes but do not offer a ready explanation for the alignments.

  12. Time-of-flight direct recoil ion scattering spectrometer

    DOEpatents

    Krauss, A.R.; Gruen, D.M.; Lamich, G.J.

    1994-09-13

    A time-of-flight direct recoil and ion scattering spectrometer beam line is disclosed. The beam line includes an ion source which injects ions into pulse deflection regions and separated by a drift space. A final optics stage includes an ion lens and deflection plate assembly. The ion pulse length and pulse interval are determined by computerized adjustment of the timing between the voltage pulses applied to the pulsed deflection regions. 23 figs.

  13. Time-of-flight direct recoil ion scattering spectrometer

    DOEpatents

    Krauss, Alan R.; Gruen, Dieter M.; Lamich, George J.

    1994-01-01

    A time of flight direct recoil and ion scattering spectrometer beam line (10). The beam line (10) includes an ion source (12) which injects ions into pulse deflection regions (14) and (16) separated by a drift space (18). A final optics stage includes an ion lens and deflection plate assembly (22). The ion pulse length and pulse interval are determined by computerized adjustment of the timing between the voltage pulses applied to the pulsed deflection regions (14) and (16).

  14. Spallation recoil and age of presolar grains in meteorites

    NASA Astrophysics Data System (ADS)

    Ott, U.; Begemann, F.

    2000-01-01

    We have determined the recoil losses from silicon carbide grain size fractions of spallation neon produced by irradiation with 1.6 GeV protons. During the irradiation the SiC grains were dispersed in paraffin wax in order to avoid re-implantation into neighboring grains. Analysis for spallogenic 21Ne of grain size separates in the size range 0.3 μm to 6 μm and comparison with the 22Na activity of the SiC+paraffin mixture indicates an effective recoil range of 2-3 μm with no apparent effect from acid treatments such as routinely used in the isolation of meteoritic SiC grains. Our results indicate that the majority of presolar SiC grains in primitive meteorites, which are ~μm-sized, will have lost essentially all spallogenic Ne produced by cosmic ray interaction in the interstellar medium. This argues against the validity of previously published presolar ages of Murchison SiC (~10 to ~130 Ma; increasing with grain size; Lewis et al., 1994), where recoil losses had been based on calculated recoil energies. It is argued that the observed variations in meteoritic SiC grain size fractions of 21Ne/22Ne ratios are more likely due to the effects of nucleosynthesis in the He burning shell of the parent AGB stars which imposes new boundary conditions on nuclear parameters and stellar models. It is suggested that spallation-Xe produced on the abundant Ba and REE in presolar SiC, rather than spallogenic Ne, may be a promising approach to the presolar age problem. There is a hint in the currently available Xe data (Lewis et al., 1994) that the large (>1 μm) grains may be younger than the smaller (<1 μm) ones.

  15. Recoil Polarization for Neutral Pion Electroproduction near the Delta Resonance

    SciTech Connect

    Kelly, James J

    2003-10-01

    We have measured angular distributions for recoil polarization in the p(e,e'p)p0 reaction at Q2»1(GeV/c)2 with 1.16 |lte| W |lte|1.36 GeV across the D resonance. The data are compared with representative models and a truncated Legendre analysis is compared with a more general multipole analysis.

  16. Recoiling from a Kick in the Head-On Case

    NASA Technical Reports Server (NTRS)

    Choi, Dae-Il; Kelly, Bernard J.; Boggs, William D.; Baker, John G.; Centrella, Joan; Van Meter, James

    2007-01-01

    Recoil "kicks" induced by gravitational radiation are expected in the inspiral and merger of black holes. Recently the numerical relativity community has begun to measure the significant kicks found when both unequal masses and spins are considered. Because understanding the cause and magnitude of each component of this kick may be complicated in inspiral simulations, we consider these effects in the context of a simple test problem. We study recoils from collisions of binaries with initially head-on trajectories, starting with the simplest case of equal masses with no spin; adding spin and varying the mass ratio, both separately and jointly. We find spin-induced recoils to be significant even in head-on configurations. Additionally, it appears that the scaling of transverse kicks with spins is consistent with post-Newtonian (PN) theory, even though the kick is generated in the nonlinear merger interaction, where PN theory should not apply. This suggests that a simple heuristic description might be effective in the estimation of spin-kicks.

  17. Absolute cross section for recoil detection of deuterium

    NASA Astrophysics Data System (ADS)

    Besenbacher, F.; Stensgaard, I.; Vase, P.

    1986-04-01

    The D( 4He, D) 4He cross section used for recoil detection of deuterium (D) has been calibrated on an absolute scale against the cross section of the D( 3He, α)p nuclear reaction which is often used for D profiling. For 4He energies ranging from 0.8 to ~1.8 MeV. the D( 4He, D) 4He cross section varies only slightly with incident energy and recoil angle θ (for 0° ⩽ 8 ⩽ 35°) and has a value of ~ 500 mb/sr which is significantly higher than the ~ 65 mb/sr c.m.s. cross section of the D( 3He, α)p nuclear reaction. For 4He energies ranging from ~ 1.9 to ~ 2.3 MeV, the D( 4He,D) 4He cross section exhibits a fairly narrow resonance peak (fwhm ~ 70 keV), with a maximum value (for θ = 0°) of ~ 8.5 b/sr, corresponding to a 4He energy of ~ 2130 keV. The large values of the cross section in connection with the described energy dependence makes the use of forward-recoil detection of D attractive for many purposes, e.g., D Jepth profiling (with an extreme gain in sensitivity), absolute concentration or coverage measurements, and lattice-location experiments by transmission channeling.

  18. Anatomy of the Binary Black Hole Recoil: A Multipolar Analysis

    NASA Technical Reports Server (NTRS)

    Schnittman, Jeremy; Buonanno, Alessandra; vanMeter, James R.; Baker, John G.; Boggs, William D.; Centrella, Joan; Kelly, Bernard J.; McWilliams, Sean T.

    2007-01-01

    We present a multipolar analysis of the recoil velocity computed in recent numerical simulations of binary black hole coalescence, for both unequal masses and non-zero, non-precessing spins. We show that multipole moments up to and including 1 = 4 are sufficient to accurately reproduce the final recoil velocity (= 98%) and that only a few dominant modes contribute significantly to it (2 95%). We describe how the relative amplitude, and more importantly, the relative phase, of these few modes control the way in which the recoil builds up throughout the inspiral, merger, and ring-down phases. We also find that the numerical results can be reproduced, to a high level of accuracy, by an effective Newtonian formula for the multipole moments obtained by replacing in the Newtonian formula the radial separation with an effective radius computed from the numerical data. Beyond the merger, the numerical results are reproduced by a superposition of three Kerr quasi-normal modes. Analytic formulae, obtained by expressing the multipole moments in terms of the fundamental QNMs of a Kerr BH, are able to explain the onset and amount of '.anti-kick" for each of the simulations. Lastly, we apply this multipolar analysis to understand the remarkable difference between the amplitudes of planar and non-planar kicks for equal-mass spinning black holes.

  19. Recoil ion charge state distribution following the beta(sup +) decay of {sup 21}Na

    SciTech Connect

    Scielzo, Nicholas D.; Freedman, Stuart J.; Fujikawa, Brian K.; Vetter, Paul A.

    2003-01-03

    The charge state distribution following the positron decay of 21Na has been measured, with a larger than expected fraction of the daughter 21Ne in positive charge states. No dependence on either the positron or recoil nucleus energy is observed. The data is compared to a simple model based on the sudden approximation. Calculations suggest a small but important contribution from recoil ionization has important consequences for precision beta decay correlation experiments detecting recoil ions.

  20. Isotopic disequilibrium of uranium: alpha-recoil damage and preferential solution effects.

    PubMed

    Fleischer, R L

    1980-02-29

    Preferential loss of uranium-234 relative to uranium-238 from rocks into solutions has long been attributed to recoiling alpha-emitting nuclei. Direct evidence has been obtained for two mechanisms, first, recoil ejection from grains, and now release by natural etching of alpha-recoil tracks. The observations have implications for radon emanation and for the storage of alpha-emitting radioactive waste. PMID:17830457

  1. Revealing compressed stops using high-momentum recoils

    NASA Astrophysics Data System (ADS)

    Macaluso, Sebastian; Park, Michael; Shih, David; Tweedie, Brock

    2016-03-01

    Searches for supersymmetric top quarks at the LHC have been making great progress in pushing sensitivity out to higher mass, but are famously plagued by gaps in coverage around lower-mass regions where the decay phase space is closing off. Within the common stop-NLSP/neutralino-LSP simplified model, the line in the mass plane where there is just enough phase space to produce an on-shell top quark remains almost completely unconstrained. Here, we show that is possible to define searches capable of probing a large patch of this difficult region, with S/B ˜ 1 and significances often well beyond 5 σ. The basic strategy is to leverage the large energy gain of LHC Run 2, leading to a sizable population of stop pair events recoiling against a hard jet. The recoil not only re-establishes a [InlineMediaObject not available: see fulltext.] signature, but also leads to a distinctive anti-correlation between the [InlineMediaObject not available: see fulltext.] and the recoil jet transverse vectors when the stops decay all-hadronically. Accounting for jet combinatorics, backgrounds, and imperfections in [InlineMediaObject not available: see fulltext.] measurements, we estimate that Run 2 will already start to close the gap in exclusion sensitivity with the first few 10s of fb-1. By 300 fb-1, exclusion sensitivity may extend from stop masses of 550 GeV on the high side down to below 200 GeV on the low side, approaching the "stealth" point at {m}_{overline{t}}={m}_t and potentially overlapping with limits from toverline{t} cross section and spin correlation measurements.

  2. (7)Be-recoil radiolabelling of industrially manufactured silica nanoparticles.

    PubMed

    Holzwarth, Uwe; Bellido, Elena; Dalmiglio, Matteo; Kozempel, Jan; Cotogno, Giulio; Gibson, Neil

    2014-01-01

    Radiolabelling of industrially manufactured nanoparticles is useful for nanoparticle dosimetry in biodistribution or cellular uptake studies for hazard and risk assessment. Ideally for such purposes, any chemical processing post production should be avoided as it may change the physico-chemical characteristics of the industrially manufactured species. In many cases, proton irradiation of nanoparticles allows radiolabelling by transmutation of a tiny fraction of their constituent atoms into radionuclides. However, not all types of nanoparticles offer nuclear reactions leading to radionuclides with adequate radiotracer properties. We describe here a process whereby in such cases nanoparticles can be labelled with (7)Be, which exhibits a physical half-life of 53.29 days and emits γ-rays of 478 keV energy, and is suitable for most radiotracer studies. (7)Be is produced via the proton-induced nuclear reaction (7)Li(p,n)(7)Be in a fine-grained lithium compound with which the nanoparticles are mixed. The high recoil energy of (7)Be atoms gives them a range that allows the (7)Be-recoils to be transferred from the lithium compound into the nanoparticles by recoil implantation. The nanoparticles can be recovered from the mixture by dissolving the lithium compound and subsequent filtration or centrifugation. The method has been applied to radiolabel industrially manufactured SiO2 nanoparticles. The process can be controlled in such a way that no alterations of the (7)Be-labelled nanoparticles are detectable by dynamic light scattering, X-ray diffraction and electron microscopy. Moreover, cyclotrons with maximum proton energies of 17-18 MeV that are available in most medical research centres could be used for this purpose. PMID:25285032

  3. A Proton Recoil Telescope Detector for Neutron Spectroscopy

    SciTech Connect

    Bocci, F.; Cinausero, M.; Rizzi, V.; Barbui, M.; Prete, G.; Andrighetto, A.; Lunardon, M.; Pesente, S.; Fontana, A.; Gemignian, G.; Bonomi, G.; Donzella, A.; Zenoni, A.; Fabris, D.; Morando, M.; Moretto, S.; Nebbia, G.; Viesti, G.

    2007-10-26

    A compact and versatile Proton Recoil Telescope (PRT) detector has been realized to measure neutron energy spectra in the range from few to hundred MeV. The PRT is a position sensitive detector made by: an active multilayer segmented plastic scintillator as neutron to proton converter, two silicon strip detectors for proton energy and position measurement and a final thick CsI(T1) scintillator to measure the residual proton energy. The detector has been tested with the {sup 13}C(d,n) reaction at Laboratori Nazionali del Sud using a 40 MeV deuteron beam.

  4. B -> D* l nu at zero recoil: an update

    SciTech Connect

    Bailey, Jon A.; Bazavov, A.; Bernard, C.; Bouchard, C.M.; DeTar, C.; El-Khadra, A.X.; Freeland, E.D.; Gamiz, E.; Gottlieb, Steven; Heller, U.M.; Hetrick, J.E.

    2010-11-01

    We present an update of our calculation of the form factor for {bar B} {yields} D*{ell}{bar {nu}} at zero recoil, with higher statistics and finer lattices. As before, we use the Fermilab action for b and c quarks, the asqtad staggered action for light valence quarks, and the MILC ensembles for gluons and light quarks (Luescher-Weisz married to 2+1 rooted staggered sea quarks). In this update, we have reduced the total uncertainty on F(1) from 2.6% to 1.7%.

  5. Projectile paths corrected for recoil and air resistance

    NASA Astrophysics Data System (ADS)

    Kemp, H. R.

    1986-01-01

    The angle of projection of a bullet is not the same as the angle of the bore of the firearm just before firing. This is because recoil alters the direction of the barrel as the bullet moves along the barrel. Neither is the angle of projection of an arrow the same as the direction of the arrow just before it is projected. The difficulty in obtaining the angle of projection limits the value of the standard equation for trajectories relative to a horizontal plane. Furthermore, air resistance makes this equation unrealistic for all but short ranges.

  6. Lung Emergencies

    MedlinePlus

    ... Emergencies Cardiac Emergencies Eye Emergencies Lung Emergencies Surgeries Lung Emergencies People with Marfan syndrome can be at ... should be considered an emergency. Symptoms of sudden lung collapse (pneumothorax) Symptoms of a sudden lung collapse ...

  7. Lung Cancer

    MedlinePlus

    ... version of this page please turn Javascript on. Lung Cancer What is Lung Cancer? How Tumors Form The body is made ... button on your keyboard.) Two Major Types of Lung Cancer There are two major types of lung ...

  8. Lung metastases

    MedlinePlus

    Metastases to the lung; Metastatic cancer to the lung ... Metastatic tumors in the lungs are cancers that developed at other places in the body (or other parts of the lungs) and spread through the ...

  9. Lung cancer

    SciTech Connect

    Aisner, J.

    1985-01-01

    This book contains 13 chapters. Some of the chapter titles are: The Pathology of Lung Cancer; Radiotherapy for Non-Small-Cell Cancer of the Lung; Chemotherapy for Non-Small-Cell Lung Cancer; Immunotherapy in the Management of Lung Cancer; Preoperative Staging and Surgery for Non-Small-Cell Lung Cancer; and Prognostic Factors in Lung Cancer.

  10. Design of the recoil mass separator St. George

    NASA Astrophysics Data System (ADS)

    Couder, M.; Berg, G. P. A.; Görres, J.; LeBlanc, P. J.; Lamm, L. O.; Stech, E.; Wiescher, M.; Hinnefeld, J.

    2008-03-01

    A recoil mass separator has been designed for the purpose of studying low energy (α,γ) reactions in inverse kinematics for beam masses up to about A=40. Their reaction rates are of importance for our understanding of energy production and nucleosynthesis during stellar and explosive helium burning. The reactions take place in a windowless He gas target at the beginning of the separator which consists of three sections. The first section selects the most abundant charge state. The Wien filter in the second section efficiently separates the intense beam from the few reaction products. In the last section the reaction products are focused into a detector system consisting of time pickup and energy detectors. In order to accept the complete kinematic cone of recoil particles for energies as low as reasonably possible we specified a large circular angular acceptance of ±40 mrad. This requires a careful minimization of higher-order aberrations. The present system has been designed to allow for a future upgrade to extend the experimental program to the analysis of (p,γ) reactions.

  11. The WITCH experiment: Acquiring the first recoil ion spectrum

    NASA Astrophysics Data System (ADS)

    Kozlov, V. Yu.; Beck, M.; Coeck, S.; Delahaye, P.; Friedag, P.; Herbane, M.; Herlert, A.; Kraev, I. S.; Tandecki, M.; Van Gorp, S.; Wauters, F.; Weinheimer, Ch.; Wenander, F.; Zákoucký, D.; Severijns, N.

    2008-10-01

    The standard model of the electroweak interaction describes β-decay in the well-known V-A form. Nevertheless, the most general Hamiltonian of a β-decay includes also other possible interaction types, e.g. scalar (S) and tensor (T) contributions, which are not fully ruled out yet experimentally. The WITCH experiment aims to study a possible admixture of these exotic interaction types in nuclear β-decay by a precise measurement of the shape of the recoil ion energy spectrum. The experimental set-up couples a double Penning trap system and a retardation spectrometer. The set-up is installed in ISOLDE/CERN and was recently shown to be fully operational. The current status of the experiment is presented together with the data acquired during the 2006 campaign, showing the first recoil ion energy spectrum obtained. The data taking procedure and corresponding data acquisition system are described in more detail. Several further technical improvements are briefly reviewed.

  12. Silicon shallow doping by erbium and oxygen recoils implantation

    NASA Astrophysics Data System (ADS)

    Feklistov, K. V.; Cherkov, A. G.; Popov, V. P.

    2016-09-01

    In order to get shallow high doping of Si with optically active complexes ErOn, Er followed by O recoils implantation was realized by means of subsequent Ar+ 250-290 keV implantation with doses 2×1015-1×1016 cm-2 through 50-nm deposited films of Er and then SiO2, accordingly. High Er concentration up to 5×1020 cm-3 to the depth of 10 nm was obtained after implantation. However, about a half of the Er implanted atoms become part of surface SiO2 during post-implantation annealing at 950 °C for 1 h in the N2 ambient under a SiO2 cap. The mechanism of Er segregation into the cap oxide following the moving amorphous-crystalline interface during recrystallization was rejected by the transmission electron microscopy (TEM) analysis. Instead, the other mechanism of immobile Er atoms and redistribution of recoil-implanted O atoms toward cap oxide was proposed. It explains the observed formation of two Er containing phases: Er-Si-O phase with a high O content adjacent to the cap oxide and deeper O depleted Er-Si phase. The correction of heat treatments is proposed in order to avoid the above-mentioned problems.

  13. A Measurement of the Recoil Polarization of Electroproduced {Lambda}(1116)

    SciTech Connect

    Simeon McAleer

    2002-01-01

    The CEBAF Large Acceptance Spectrometer at the Thomas Jefferson National Laboratory was used to study the reaction e + p {yields} e{prime} + K{sup +} + {Lambda}(1116) for events where {Lambda}(1116) subsequently decayed via the channel {Lambda}(1116) {yields} p + {pi}{sup -}. Data were taken at incident electron beam energies of 2.5, 4.0, and 4.2 GeV during the 1999 E1C run period. They hyperon production spectra span the Q{sup 2} range from 0.5 to 2.8 GeV{sup 2} and nearly the entire range in the center of mass angles. The proton angular distribution in the {Lambda}(1116) rest frame is used to deduce the recoil polarization of the hyperon, and the W and cos {theta}{sub cm}{sup K+} dependence of the recoil polarization will be presented. The data show sizeable negative polarizations for the {Lambda}(1116) as a function of both cos {theta}{sub cm}{sup K+} and W.

  14. Improvements of the DRAGON recoil separator at ISAC

    NASA Astrophysics Data System (ADS)

    Vockenhuber, C.; Buchmann, L.; Caggiano, J.; Chen, A. A.; D'Auria, J. M.; Davis, C. A.; Greife, U.; Hussein, A.; Hutcheon, D. A.; Ottewell, D.; Ouellet, C. O.; Parikh, A.; Pearson, J.; Ruiz, C.; Ruprecht, G.; Trinczek, M.; Zylberberg, J.

    2008-10-01

    The DRAGON (Detector of Recoils And Gammas Of Nuclear reactions) is used to measure radiative proton and alpha capture reaction rates involving both stable and radioactive, heavy-ion reactants at the TRIUMF-ISAC high intensity radioactive beam facility. Completed in 2001 it has been used for several challenging studies for nuclear astrophysics, e.g. 12C(α, γ)16O, 21Na(p, γ)22Mg, 26gAl(p, γ)27Si and 40Ca(α, γ)44Ti. Since initial operation, a number of improvements have been incorporated which are described here. These include a beam centering monitor based on a CCD camera, a mechanical iris to skim of beam halo, a solid state stripper acting as a charge state booster for beams with A ≳ 30, beta and gamma detectors to monitor beam intensity and to determine beam contamination in experiments with radioactive beam and the ionization chamber for both recoil identification and isobar separation.

  15. Numerical simulations of spiral galaxy formation and recoiling black holes

    NASA Astrophysics Data System (ADS)

    Guedes, Javiera M.

    This thesis discusses two major topics in regard to the formation and evolution of galaxies and their central massive black holes (MBH). Part 1 explores the detectability of recoiling massive back as kinematically and spatially offset active galactic nuclei (AGN). Chapter 3 is devoted to understanding the effect of an aspherical dark matter potential on the trajectories of the MBHs. This is done through collisionless N-body simulations of kicked black holes in the Via Lactea I halo and through a semi-analytical model that accounts for the evolution of the halo's triaxiality as a function of radius over cosmic time. We find that the return time of MBHs that wander through a differentially triaxial halo is significantly extended in comparison with spherical models. This is because their trajectories are become highly non-radial which prevents them from passing near the halo's center, where dynamical friction is most efficient. Chapter 4 puts recoiling MBHs into context. Here we carry out N-body + SPH simulations of recoiling MBHs in high-resolution galaxy mergers with mass ratios 1:1 (Mayer et al. 2007), 1:4, and 1:10 (Callegari et al. 2009). We study not only the trajectories and return times of these black holes, but also their detectability as spatially/kinematically offset AGN. We find that the probability of detection of these MBHs is extremely low. The detection of large kinematic offsets requires that the MBH have relative offset velocities Deltav > 600km s-1 at the time of observation. This is unlikely due to (1) the low probability of large recoils to occur from a general-relativistic viewpoint, and (2) the short time scale during which the MBH can sustain large velocities even if the initial kick is high. The large amounts of gas funneled to the center of the host potential during mergers also prevents MBHs from reaching large apocenter distances, which hampers their detection as spatially offset AGN, especially at high redshift when recoil events are

  16. Monitoring of physics performance of ILC Software based on Higgs Recoil Mass

    NASA Astrophysics Data System (ADS)

    Volkova, E.; Voutsinas, G.

    2016-02-01

    We discuss a part of ILC software development, that allow us to make automated testing of ILC results. The testing code consists of automated everyday Higgs recoil mass analysis and compares Higgs recoil mass with one of the previous day result. This code uses the result of generation, Mokka simulation and Marlin reconstruction of ILC events.

  17. Optimal control of gun recoil in direct fire using magnetorheological absorbers

    NASA Astrophysics Data System (ADS)

    Singh, Harinder J.; Wereley, Norman M.

    2014-05-01

    Optimal control of a gun recoil absorber is investigated for minimizing recoil loads and maximizing rate of fire. A multi-objective optimization problem was formulated by considering the mechanical model of the recoil absorber employing a spring and a magnetorheological (MR) damper. The damper forces are predicted by evaluating pressure drops using a nonlinear Bingham-plastic model. The optimization methodology provides multiple optimal design configurations with a trade-off between recoil load minimization and increased rate of fire. The configurations with low or high recoil loads imply low or high rate of fire, respectively. The gun recoil absorber performance is also analyzed for perturbations in the firing forces. The adaptive control of the MR damper for varying gun firing forces provides a smooth operation by returning the recoil mass to its battery position (ready to reload and fire) without incurring an end-stop impact. Furthermore, constant load transmissions are observed with respect to the recoil stroke by implementing optimal control during the simulated firing events.

  18. COSY Simulations to Guide Commissioning of the St. George Recoil Mass Separator

    NASA Astrophysics Data System (ADS)

    Schmitt, Jaclyn; Moran, Michael; Seymour, Christopher; Gilardy, Gwenaelle; Meisel, Zach; Couder, Manoel

    2015-10-01

    The goal of St. George (STrong Gradient Electromagnetic Online Recoil separator for capture Gamma ray Experiments) is to measure (α, γ) cross sections relevant to stellar helium burning. Recoil separators such as St. George are able to more closely approach the low astrophysical energies of interest because they collect reaction recoils rather than γ-rays, and thus are not limited by room background. In order to obtain an accurate cross section measurement, a recoil separator must be able to collect all recoils over their full range of expected energy and angular spread. The energy acceptance of St. George is currently being measured, and the angular acceptance will be measured soon. Here we present the results of COSY ion optics simulations and magnetic field analyses which were performed to help guide the commissioning measurements and diagnostic upgrades required to complete those measurements. National Science Foundation Research Experiences for Undergraduates program.

  19. Deconvoluting nonaxial recoil in Coulomb explosion measurements of molecular axis alignment

    NASA Astrophysics Data System (ADS)

    Christensen, Lauge; Christiansen, Lars; Shepperson, Benjamin; Stapelfeldt, Henrik

    2016-08-01

    We report a quantitative study of the effect of nonaxial recoil during Coulomb explosion of laser-aligned molecules and introduce a method to remove the blurring caused by nonaxial recoil in the fragment-ion angular distributions. Simulations show that nonaxial recoil affects correlations between the emission directions of fragment ions differently from the effect caused by imperfect molecular alignment. The method, based on analysis of the correlation between the emission directions of the fragment ions from Coulomb explosion, is used to deconvolute the effect of nonaxial recoil from experimental fragment angular distributions. The deconvolution method is then applied to a number of experimental data sets to correct the degree of alignment for nonaxial recoil, to select optimal Coulomb explosion channels for probing molecular alignment, and to estimate the highest degree of alignment that can be observed from selected Coulomb explosion channels.

  20. Electron recombination in low-energy nuclear recoils tracks in liquid argon

    NASA Astrophysics Data System (ADS)

    Wojcik, M.

    2016-02-01

    This paper presents an analysis of electron-ion recombination processes in ionization tracks of recoiled atoms in liquid argon (LAr) detectors. The analysis is based on the results of computer simulations which use realistic models of electron transport and reactions. The calculations reproduce the recent experimental results of the ionization yield from 6.7 keV nuclear recoils in LAr. The statistical distribution of the number of electrons that escape recombination is found to deviate from the binomial distribution, and estimates of recombination fluctuations for nuclear recoils tracks are obtained. A study of the recombination kinetics shows that a significant part of electrons undergo very fast static recombination, an effect that may be responsible for the weak drift-field dependence of the ionization yield from nuclear recoils in some noble liquids. The obtained results can be useful in the search for hypothetical dark matter particles and in other studies that involve detection of recoiled nuclei.

  1. B{yields}D* at zero recoil revisited

    SciTech Connect

    Gambino, Paolo; Mannel, Thomas; Uraltsev, Nikolai

    2010-06-01

    We examine the B{yields}D* form factor at zero recoil using a continuum QCD approach rooted in the heavy quark sum rules framework. A refined evaluation of the radiative corrections as well as the most recent estimates of higher-order power terms together with more careful continuum calculation are included. An upper bound on the form factor of F(1) < or approx. 0.93 is derived, based on just the positivity of inelastic contributions. A model-independent estimate of the inelastic contributions shows they are quite significant, lowering the form factor by about 6% or more. This results in an unbiased estimate F(1){approx_equal}0.86 with about 3% uncertainty in the central value.

  2. Dielectric barrier structure with hollow electrodes and its recoil effect

    SciTech Connect

    Yu, Shuang; Chen, Qunzhi; Liu, Jiahui; Wang, Kaile; Jiang, Zhe; Sun, Zhili; Zhang, Jue; Fang, Jing

    2015-06-15

    A dielectric barrier structure with hollow electrodes (HEDBS), in which gas flow oriented parallel to the electric field, was proposed. Results showed that with this structure, air can be effectively ignited, forming atmospheric low temperature plasma, and the proposed HEDBS could achieve much higher electron density (5 × 10{sup 15}/cm{sup 3}). It was also found that the flow condition, including outlet diameter and flow rate, played a key role in the evolution of electron density. Optical emission spectroscopy diagnostic results showed that the concentration of reactive species had the same variation trend as the electron density. The simulated distribution of discharge gas flow indicated that the HEDBS had a strong recoil effect on discharge gas, and could efficiently promote generating electron density as well as reactive species.

  3. Molecular Dynamics Simulation of Energetic Uranium Recoil Damage in Zircon

    SciTech Connect

    Devanathan, Ram; Corrales, Louis R.; Weber, William J.; Chartier, Alain; Meis, Constantin

    2006-10-11

    Defect production and amorphization due to energetic uranium recoils in zircon (ZrSiO4), which is a promising ceramic nuclear waste form, is studied using molecular dynamics simulations with a partial charge model. An algorithm that distinguishes between undamaged crystal, crystalline defects and amorphous regions is used to develop a fundamental understanding of the primary damage state. The amorphous cascade core is separated from the surrounding crystal by a defect-rich region. Small, chemically inhomogeneous amorphous clusters are also produced around the core. The amorphous regions consist of under-coordinated Zr and polymerized Si leading to amorphization and phase separation on a nanometer scale into Zr- and Si-rich regions. This separation could play an important role in the experimentally observed formation of nanoscale ZrO2 in ZrSiO4 irradiated at elevated temperatures.

  4. Proton recoil spectroscopy 400 meters from a fission neutron source

    SciTech Connect

    Stanka, M.B.

    1994-12-31

    Neutron kerma and spectrum measurements have been made at the US Army Pulse Radiation Facility (APRF) to 400m in an air-over-ground geometry from a fission neutron source and have been compared to Monte Carlo transport calculations. The neutron spectra measurements were made using a rotating neutron spectrometer. This spectrometer consists of four spherical proton-recoil detectors mounted on a common rotating base. Detector radius, gas composition, and pressure have been varied to allow sensitivity over a neutron range of 50 keV to 4.5 MeV. Neutron kerma was determined by using the Kerr soft-tissue kerma factors. Measured neutron kerma agreed with the calculated neutron kerma to within 5%. Comparisons with other neutron spectrometers such as NE213 and Bonner Spheres are presented and agreement between the different spectrometers is better than 20%.

  5. Recoil Polarization for {delta} Excitation in Pion Electroproduction

    SciTech Connect

    Kelly, J.J.; Beise, E.J.; Breuer, H.; Chang, C.C.; Chant, N.S.; Roos, P.G.; Roche, R.E.; McAleer, S.; Meekins, D.; Chai, Z.; Gayou, O.; Bertozzi, W.; Gilad, S.; Higinbotham, D.W.; Rvachev, M.; Sirca, S.; Suleiman, R.; Zheng, X.; Zhu, L.; Jones, M.K.

    2005-09-02

    We measured angular distributions of recoil-polarization response functions for neutral pion electroproduction for W=1.23 GeV at Q{sup 2}=1.0 (GeV/c){sup 2}, obtaining 14 separated response functions plus 2 Rosenbluth combinations; of these, 12 have been observed for the first time. Dynamical models do not describe quantities governed by imaginary parts of interference products well, indicating the need for adjusting magnitudes and phases for nonresonant amplitudes. We performed a nearly model-independent multipole analysis and obtained values for Re (S{sub 1+}/M{sub 1+})=-(6.84{+-}0.15)% and Re (E{sub 1+}/M{sub 1+})=-(2.91{+-}0.19)% that are distinctly different from those from the traditional Legendre analysis based upon M{sub 1+} dominance and l{sub {pi}}{<=}1 truncation.

  6. Recoil polarization for delta excitation in pion electroproduction.

    PubMed

    Kelly, J J; Roché, R E; Chai, Z; Jones, M K; Gayou, O; Sarty, A J; Frullani, S; Aniol, K; Beise, E J; Benmokhtar, F; Bertozzi, W; Boeglin, W U; Botto, T; Brash, E J; Breuer, H; Brown, E; Burtin, E; Calarco, J R; Cavata, C; Chang, C C; Chant, N S; Chen, J-P; Coman, M; Crovelli, D; De Leo, R; Dieterich, S; Escoffier, S; Fissum, K G; Garde, V; Garibaldi, F; Georgakopoulus, S; Gilad, S; Gilman, R; Glashausser, C; Hansen, J-O; Higinbotham, D W; Hotta, A; Huber, G M; Ibrahim, H; Iodice, M; de Jager, C W; Jiang, X; Klimenko, A; Kozlov, A; Kumbartzki, G; Kuss, M; Lagamba, L; Laveissière, G; Lerose, J J; Lindgren, R A; Liyanage, N; Lolos, G J; Lourie, R W; Margaziotis, D J; Marie, F; Markowitz, P; McAleer, S; Meekins, D; Michaels, R; Milbrath, B D; Mitchell, J; Nappa, J; Neyret, D; Perdrisat, C F; Potokar, M; Punjabi, V A; Pussieux, T; Ransome, R D; Roos, P G; Rvachev, M; Saha, A; Sirca, S; Suleiman, R; Strauch, S; Templon, J A; Todor, L; Ulmer, P E; Urciuoli, G M; Weinstein, L B; Wijesooriya, K; Wojtsekhowski, B; Zheng, X; Zhu, L

    2005-09-01

    We measured angular distributions of recoil-polarization response functions for neutral pion electroproduction for W = 1.23 GeV at Q(2) = 1.0 (GeV/c)(2), obtaining 14 separated response functions plus 2 Rosenbluth combinations; of these, 12 have been observed for the first time. Dynamical models do not describe quantities governed by imaginary parts of interference products well, indicating the need for adjusting magnitudes and phases for nonresonant amplitudes. We performed a nearly model-independent multipole analysis and obtained values for Re (S(1+)/M(1+)) = -(6.84 +/- 0.15)% and Re (E(1+)/M(1+)) = -(2.91 +/- 0.19)% that are distinctly different from those from the traditional Legendre analysis based upon M1+ dominance and ll(pi) < or = 1 truncation. PMID:16196919

  7. Calibration of a compact magnetic proton recoil neutron spectrometer

    NASA Astrophysics Data System (ADS)

    Zhang, Jianfu; Ouyang, Xiaoping; Zhang, Xianpeng; Ruan, Jinlu; Zhang, Guoguang; Zhang, Xiaodong; Qiu, Suizheng; Chen, Liang; Liu, Jinliang; Song, Jiwen; Liu, Linyue; Yang, Shaohua

    2016-04-01

    Magnetic proton recoil (MPR) neutron spectrometer is considered as a powerful instrument to measure deuterium-tritium (DT) neutron spectrum, as it is currently used in inertial confinement fusion facilities and large Tokamak devices. The energy resolution (ER) and neutron detection efficiency (NDE) are the two most important parameters to characterize a neutron spectrometer. In this work, the ER calibration for the MPR spectrometer was performed by using the HI-13 tandem accelerator at China Institute of Atomic Energy (CIAE), and the NDE calibration was performed by using the neutron generator at CIAE. The specific calibration techniques used in this work and the associated accuracies were discussed in details in this paper. The calibration results were presented along with Monte Carlo simulation results.

  8. Spectroscopy of {sup 144}Ho using recoil-isomer tagging

    SciTech Connect

    Mason, P. J. R; Cullen, D. M.; Scholey, C.; Greenlees, P. T.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Nyman, M.; Peura, P.; Puurunen, A.; Rahkila, P.; Ruotsalainen, P.; Sorri, J.; Saren, J.; Uusitalo, J.; Xu, F. R.

    2010-02-15

    Excited states in the proton-unbound odd-odd nucleus {sup 144}Ho have been populated using the {sup 92}Mo({sup 54}Fe,pn){sup 144}Ho reaction and studied using the recoil-isomer-tagging technique. The alignment properties and signature splitting of the rotational band above the I{sup p}i=(8{sup +}){sup 144m}Ho isomer have been analyzed and the isomer confirmed to have a pih{sub 11/2} x nuh{sub 11/2} two-quasiparticle configuration. The configuration-constrained blocking method has been used to calculate the shapes of the ground and isomeric states, which are both predicted to have triaxial nuclear shapes with |gamma|approx =24 deg.

  9. Recoil Polarization for Delta Excitation in Pion Electroproduction

    SciTech Connect

    J. J. Kelly; R. E. Roche; Z. Chai; M. K. Jones; O. Gayou; A. J. Sarty; S. Frullani; K. Aniol; E. J. Beise; F. Benmokhtar; W. Bertozzi; W. U. Boeglin; T. Botto; E. J. Brash; H. Breuer; E. Brown; E. Burtin; J. R. Calarco; C. Cavata; C. C. Chang; N. S. Chant; J.-P. Chen; M. Coman; D. Crovelli; R. De Leo; S. Dieterich; S. Escoffier; K. G. Fissum; V. Garde; F. Garibaldi; S. Georgakopoulus; S. Gilad; R. Gilman; C. Glashausser; J.-O. Hansen; D. W. Higinbotham; A. Hotta; G. M. Huber; H. Ibrahim; M. Iodice; C. W. de Jager; X. Jiang; A. Klimenko; A. Kozlov; G. Kumbartzki; M. Kuss; L. Lagamba; G. Laveissiere; J. J. LeRose; R. A. Lindgren; N. Liyanage; G. J. Lolos; R. W. Lourie; D. J. Margaziotis; F. Marie; P. Markowitz; S. McAleer; D. Meekins; R. Michaels; B. D. Milbrath; J. Mitchell; J. Nappa; D. Neyret; C. F. Perdrisat; M. Potokar; V. A. Punjabi; T. Pussieux; R. D. Ransome; P. G. Roos; M. Rvachev; A. Saha; S. Sirca; R. Suleiman; S. Strauch; J. A. Templon; L. Todor; P. E. Ulmer; G. M. Urciuoli; L. B. Weinstein; K. Wijesooriya; B. Wojtsekhowski; X. Zheng; and L. Zhu

    2005-08-01

    We measured angular distributions of recoil-polarization response functions for neutral pion electroproduction for W=1.23 GeV at Q{sup 2}=1.0 (GeV/c){sup 2}, obtaining 14 separated response functions plus 2 Rosenbluth combinations; of these, 12 have been observed for the first time. Dynamical models do not describe quantities governed by imaginary parts of interference products well, indicating the need for adjusting magnitudes and phases for nonresonant amplitudes. We performed a nearly model-independent multipole analysis and obtained values for Re(S1+/M1+)=-(6.84+/-0.15)% and Re(E1+/M1+)=-(2.91+/-0.19)% that are distinctly different from those from the traditional Legendre analysis based upon M1+ dominance and sp truncation.

  10. Measurements of the elastic electromagnetic form factor ratio {mu}pGEp/GMp via polarization transfer

    SciTech Connect

    Olivier Gayou; Oleksandr Glamazdin; Andrei Afanasev; Arunava Saha; Brendan Fox; Bogdan Wojtsekhowski; C. Chang; Cathleen Jones; Charles Glashausser; Charles Perdrisat; D. Crovelli; Daniel Simon; David Meekins; Demetrius Margaziotis; Dipangkar Dutta; Edgar Kooijman; Elaine Schulte; Edward Brash; Edward Kinney; Eugene Chudakov; Feng Xiong; Franco Garibaldi; Garth Huber; Gerfried Kumbartzki; Guido Urciuoli; Haiyan Gao; Jordan Hovdebo; James Kelly; Javier Gomez; Jens-Ole Hansen; Jian-Ping Chen; John Calarco; John LeRose; Joseph Mitchell; Juncai Gao; Konrad Aniol; Kamal Benslama; Kathy McCormick; Cornelis De Jager; Cornelis de Jager; Kevin Fissum; Krishni Wijesooriya; Louis Bimbot; Ludyvine Morand; Luminita Todor; Moskov Amarian; Marat Rvachev; Mark Jones; Martin Epstein; Meihua Liang; Michael Kuss; Nilanga Liyanage; Adam Sarty; Paul Ulmer; Pete Markowitz; Peter Bosted; R. Holt; Riad Suleiman; Richard Lindgren; Rikki Roche; Robert Michaels; Roman Pomatsalyuk; Ronald Gilman; Ronald Ransome; Stephen Becher; Scott Dumalski; Salvatore Frullani; Seonho Choi; Sergey Malov; Sonja Dieterich; Steffen Strauch; Steve Churchwell; Ting Chang; Viktor Gorbenko; Vina Punjabi; Wang Xu; Xiangdong Ji; Zein-Eddine Meziani; Zhengwei Chai

    2001-09-01

    We present measurements of the ratio of the proton elastic electromagnetic form factors, {mu}pGEp/GMp. The Jefferson Lab Hall A Focal Plane Polarimeter was used to determine the longitudinal and transverse components of the recoil proton polarization in ep elastic scattering; the ratio of these polarization components is proportional to the ratio of the two form factors. These data reproduce the observation of Jones et al. [Phys. Rev. Lett. 84, 1398 (2000)], that the form factor ratio decreases significantly from unity above Q2 = 1 GeV2.

  11. A Study of Nuclear Recoils in Liquid Argon Time Projection Chamber for the Direct Detection of WIMP Dark Matter

    SciTech Connect

    Cao, Huajie

    2014-11-01

    Robust results of WIMP direct detection experiments depend on rm understandings of nuclear recoils in the detector media. This thesis documents the most comprehensive study to date on nuclear recoils in liquid argon - a strong candidate for the next generation multi-ton scale WIMP detectors. This study investigates both the energy partition from nuclear recoil energy to secondary modes (scintillation and ionization) and the pulse shape characteristics of scintillation from nuclear recoils.

  12. Alpha-recoil thorium-234: dissolution into water and the uranium-234/uranium-238 disequilibrium in nature.

    PubMed

    Kigoshi, K

    1971-07-01

    The rate of ejection of alpha-recoil thorium-234 into solution from the surface of zircon sand gives an alpha-recoil range of 550 angstroms. The alpha-recoil thorium-234 atoms ejected into the groundwater may supply excess uranium-234. In pelagic sediments, ejected alpha-recoil thorium-234 may contribute to the supply of mobile uranium-234 in the sedimentary column. PMID:17747313

  13. α -decay chains of recoiled superheavy nuclei: A theoretical study

    NASA Astrophysics Data System (ADS)

    Niyti, Sawhney, Gudveen; Sharma, Manoj K.; Gupta, Raj K.

    2015-05-01

    A systematic theoretical study of α -decay half-lives in the superheavy mass region of the periodic table of elements is carried out by extending the quantum-mechanical fragmentation theory based on the preformed cluster model (PCM) to include temperature (T ) dependence in its built-in preformation and penetration probabilities of decay fragments. Earlier, the α -decay chains of the isotopes of Z =115 were investigated by using the standard PCM for spontaneous decays, with"hot-optimum" orientation effects included, which required a constant scaling factor of 104 to approach the available experimental data. In the present approach of the PCM (T ≠0 ), the temperature effects are included via the recoil energy of the residual superheavy nucleus (SHN) left after x -neutron emission from the superheavy compound nucleus. The important result is that the α -decay half-lives calculated by the PCM (T ≠0 ) match the experimental data nearly exactly, without using any scaling factor of the type used in the PCM. Note that the PCM (T ≠0 ) is an equivalent of the dynamical cluster-decay model for heavy-ion collisions at angular momentum ℓ =0 . The only parameter of model is the neck-length parameter Δ R , which for the calculated half-lives of α -decay chains of various isotopes of Z =113 to 118 nuclei formed in "hot-fusion" reactions is found to be nearly constant, i.e., Δ R ≈0.95 ±0.05 fm for all the α -decay chains studied. The use of recoiled residue nucleus as a secondary heavy-ion beam for nuclear reactions has also been suggested in the past.

  14. Lung Diseases

    MedlinePlus

    ... many disorders affecting the lungs, such as asthma, COPD, infections like influenza, pneumonia and tuberculosis, lung cancer, and many other breathing problems. Some lung diseases can lead to respiratory failure. Dept. of Health and Human Services Office on Women's Health

  15. Collapsed Lung

    MedlinePlus

    A collapsed lung happens when air enters the pleural space, the area between the lung and the chest wall. If it is a ... is called pneumothorax. If only part of the lung is affected, it is called atelectasis. Causes of ...

  16. Lung surgery

    MedlinePlus

    ... balloon-like tissues (blebs) that cause lung collapse ( pneumothorax ) Wedge resection, to remove part of a lobe ... Treat injuries that cause lung tissue to collapse ( pneumothorax or hemothorax ) Treat permanently collapsed lung tissue ( atelectasis ) ...

  17. Collapsed Lung

    MedlinePlus

    A collapsed lung happens when air enters the pleural space, the area between the lung and the chest wall. If it is a total collapse, it is called pneumothorax. If only part of the lung is affected, ...

  18. Lung disease

    MedlinePlus

    ... the lungs to take in oxygen and release carbon dioxide. People with this type of lung disorder often ... the lungs to take up oxygen and release carbon dioxide. These diseases may also affect heart function. An ...

  19. Spring or string: does tendon elastic action influence wing muscle mechanics in bat flight?

    PubMed

    Konow, Nicolai; Cheney, Jorn A; Roberts, Thomas J; Waldman, J Rhea S; Swartz, Sharon M

    2015-10-01

    Tendon springs influence locomotor movements in many terrestrial animals, but their roles in locomotion through fluids as well as in small-bodied mammals are less clear. We measured muscle, tendon and joint mechanics in an elbow extensor of a small fruit bat during ascending flight. At the end of downstroke, the tendon was stretched by elbow flexion as the wing was folded. At the end of upstroke, elastic energy was recovered via tendon recoil and extended the elbow, contributing to unfurling the wing for downstroke. Compared with a hypothetical 'string-like' system lacking series elastic compliance, the tendon spring conferred a 22.5% decrease in muscle fascicle strain magnitude. Our findings demonstrate tendon elastic action in a small flying mammal and expand our understanding of the occurrence and action of series elastic actuator mechanisms in fluid-based locomotion. PMID:26423848

  20. A Novel method for modeling the recoil in W boson events at hadron collider

    SciTech Connect

    Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Abolins, Maris A.; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Aguilo, Ernest; Ahsan, Mahsana; Alexeev, Guennadi D.; Alkhazov, Georgiy D.; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls /Northeastern U.

    2009-07-01

    We present a new method for modeling the hadronic recoil in W {yields} {ell}{nu} events produced at hadron colliders. The recoil is chosen from a library of recoils in Z {yields} {ell}{ell} data events and overlaid on a simulated W {yields} {ell}{nu} event. Implementation of this method requires that the data recoil library describe the properties of the measured recoil as a function of the true, rather than the measured, transverse momentum of the boson. We address this issue using a multidimensional Bayesian unfolding technique. We estimate the statistical and systematic uncertainties from this method for the W boson mass and width measurements assuming 1 fb{sup -1} of data from the Fermilab Tevatron. The uncertainties are found to be small and comparable to those of a more traditional parameterized recoil model. For the high precision measurements that will be possible with data from Run II of the Fermilab Tevatron and from the CERN LHC, the method presented in this paper may be advantageous, since it does not require an understanding of the measured recoil from first principles.

  1. Retention studies of recoiling daughter nuclides of 225Ac in polymer vesicles.

    PubMed

    Wang, G; de Kruijff, R M; Rol, A; Thijssen, L; Mendes, E; Morgenstern, A; Bruchertseifer, F; Stuart, M C A; Wolterbeek, H T; Denkova, A G

    2014-02-01

    Alpha radionuclide therapy is steadily gaining importance and a large number of pre-clinical and clinical studies have been carried out. However, due to the recoil effects the daughter recoil atoms, most of which are alpha emitters as well, receive energies that are much higher than the energies of chemical bonds resulting in decoupling of the radionuclide from common targeting agents. Here, we demonstrate that polymer vesicles (i.e. polymersomes) can retain recoiling daughter nuclei based on an experimental study examining the retention of (221)Fr and (213)Bi when encapsulating (225)Ac. PMID:24374072

  2. High-energy recoil-ion emission in keV heavy-ion surface collisions

    NASA Astrophysics Data System (ADS)

    van Someren, B.; Rudolph, H.; Urazgil'din, I. F.; van Emmichoven, P. A. Zeijlmans; Niehaus, A.

    1997-11-01

    For keV Xe +, Kr + and Ar + ions incident at 30° on Cu(110) we have observed the emission of negatively charged particles with energies up to about 40% of the primary energy. By time-of-flight techniques we have found that electrons are emitted with energies up to 80 eV, whereas the negatively charged high-energy particles are Cu - recoil ions. High-energy Cu + ions have also been found. Simple energy and momentum conservation arguments show that such high recoil energies are indeed possible for multiple collision events in which the primary recoil ion scatters off one or more Cu atoms.

  3. Nuclear recoil energy scale in liquid xenon with application to the direct detection of dark matter

    SciTech Connect

    Sorensen, P; Dahl, C E

    2011-02-14

    We show for the first time that the quenching of electronic excitation from nuclear recoils in liquid xenon is well-described by Lindhard theory, if the nuclear recoil energy is reconstructed using the combined (scintillation and ionization) energy scale proposed by Shutt et al.. We argue for the adoption of this perspective in favor of the existing preference for reconstructing nuclear recoil energy solely from primary scintillation. We show that signal partitioning into scintillation and ionization is well-described by the Thomas-Imel box model. We discuss the implications for liquid xenon detectors aimed at the direct detection of dark matter.

  4. The quasielastic 2H(e,e'p)n reaction at high recoil momenta

    SciTech Connect

    D. Crovelli; Konrad Aniol; Javier Gomez; John LeRose; Arunava Saha; Paul Ulmer; Vina Punjabi; Richard Lindgren; Charles Perdrisat; David Meekins; Joseph Mitchell; Mark Jones; Robert Michaels; Bogdan Wojtsekhowski; Hartmuth Arenhoevel; Michael Finn; Jens-Ole Hansen; Riad Suleiman; Kevin Fissum; Sergey Malov; Cornelis De Jager; Cornelis de Jager; Rikki Roche; Michael Kuss; Eugene Chudakov; Sabine Jeschonnek; Franck Sabatie; Luminita Todor; Meihua Liang; Olivier Gayou; Jian-Ping Chen

    2001-11-01

    The 2H(e,e'p)n cross section was measured in Hall A of the Thomas Jefferson National Accelerator Facility (JLab) in quasielastic kinematics (x=0.96) at a four-momentum transfer squared, Q{sup 2}=0.67 (GeV/c){sup 2}. The experiment was performed in fixed electron kinematics for recoil momenta from zero to 550 MeV/c. Though the measured cross section deviates by 1-2 sigma from a state-of-the-art calculation at low recoil momenta, it agrees at high recoil momenta where final state interactions (FSI) are predicted to be large.

  5. Recoil-nucleus spectra in the interaction of cosmic-ray protons with spacecraft electronics

    SciTech Connect

    Chuvilskaya, T. V.; Shirokova, A. A.; Kadmenskii, A. G.; Chechenin, N. G.

    2008-07-15

    The cross sections for nuclear reactions induced by 50-to 1000-MeV protons in silicon and the angular distributions of products of these reactions are calculated, along with the recoil-nucleus spectra. The recoil-nucleus spectra are shown to contain a monotonically decreasing portion and a recoil peak, which is manifested most clearly at incident-proton energies in excess of 100 MeV. The possibility of employing these results to derive more reliable estimates of single-event upsets in onboard spacecraft electronics is discussed.

  6. Elastically Decoupling Dark Matter

    NASA Astrophysics Data System (ADS)

    Kuflik, Eric; Perelstein, Maxim; Lorier, Nicolas Rey-Le; Tsai, Yu-Dai

    2016-06-01

    We present a novel dark matter candidate, an elastically decoupling relic, which is a cold thermal relic whose present abundance is determined by the cross section of its elastic scattering on standard model particles. The dark matter candidate is predicted to have a mass ranging from a few to a few hundred MeV, and an elastic scattering cross section with electrons, photons and/or neutrinos in the 10-3- 1 fb range.

  7. Elastically Decoupling Dark Matter.

    PubMed

    Kuflik, Eric; Perelstein, Maxim; Lorier, Nicolas Rey-Le; Tsai, Yu-Dai

    2016-06-01

    We present a novel dark matter candidate, an elastically decoupling relic, which is a cold thermal relic whose present abundance is determined by the cross section of its elastic scattering on standard model particles. The dark matter candidate is predicted to have a mass ranging from a few to a few hundred MeV, and an elastic scattering cross section with electrons, photons and/or neutrinos in the 10^{-3}-1  fb range. PMID:27314712

  8. Elastic internal flywheel gimbal

    SciTech Connect

    Rabenhorst, D.W.

    1981-01-13

    An elastic joint mounting and rotatably coupling a rotary inertial energy storage device or flywheel, to a shaft, the present gimbal structure reduces vibration and shock while allowing precession of the flywheel without the need for external gimbal mounts. The present elastic joint usually takes the form of an annular elastic member either integrally formed into the flywheel as a centermost segment thereof or attached to the flywheel or flywheel hub member at the center thereof, the rotary shaft then being mounted centrally to the elastic member.

  9. A study of intrinsic statistical variation for low-energy nuclear recoils in liquid xenon detector for dark matter searches

    NASA Astrophysics Data System (ADS)

    Wang, Lu; Wei, Wenzhao; Mei, Dongming; Cubed Collaboration

    2015-10-01

    Noble liquid xenon experiments, such as XENON100, LUX, XENON 1-Ton, and LZ are large dark matter experiments directly searches for weakly interacting massive particles (WIMPs). One of the most important features is to discriminate nuclear recoils from electronic recoils. Detector response is generally calibrated with different radioactive sources including 83mKr, tritiated methane, 241AmBe, 252Cf, and DD-neutrons. The electronic recoil and nuclear recoil bands have been determined by these calibrations. However, the width of nuclear recoil band needs to be fully understood. We derive a theoretical model to understand the correlation of the width of nuclear recoil band and intrinsic statistical variation. In addition, we conduct experiments to validate the theoretical model. In this paper, we present the study of intrinsic statistical variation contributing to the width of nuclear recoil band. DE-FG02-10ER46709 and the state of South Dakota.

  10. Lung cancer

    PubMed Central

    Dong, Jie; Kislinger, Thomas; Jurisica, Igor; Wigle, Dennis A.

    2010-01-01

    High-throughput genomic data for both lung development and lung cancer continue to accumulate. Significant molecular intersection between these two processes has been hypothesized due to overlap in phenotypes and genomic variation. Examining the network biology of both cancer and development of the lung may shed functional light on the individual signaling modules involved. Stem cell biology may explain a portion of this network intersection and consequently studying lung organogenesis may have relevance for understanding lung cancer. This review summarizes our understanding of the potential overlapping mechanisms involved in lung development and lung tumorigenesis. PMID:19202349

  11. Fast thermometry for trapped atoms using recoil-induced resonance

    NASA Astrophysics Data System (ADS)

    Zhao, Yan-Ting; Su, Dian-Qiang; Ji, Zhong-Hua; Zhang, Hong-Shan; Xiao, Lian-Tuan; Jia, Suo-Tang

    2015-09-01

    We have employed recoil-induced resonance (RIR) with linewidth on the order of 10 kHz to demonstrate the fast thermometry for ultracold atoms. We theoretically calculate the absorption spectrum of RIR which agrees well with the experimental results. The temperature of the ultracold sample derived from the RIR spectrum is T = 84±4.5 μK, which is close to 85 μK that measured by the method of time-of-flight absorption imaging. To exhibit the fast measurement advantage in applying RIR to the ultracold atom thermometry, we study the dependence of ultracold sample temperature on the trapping beam frequency detuning. This method can be applied to determine the translational temperature of molecules in photoassociation dynamics. Project supported by the National Basic Research Development Program of China (Grant No. 2012CB921603), the National High Technology Research and Development Program of China (Grant No. 2011AA010801), the National Natural Science Foundation of China (Grant Nos. 61275209, 11304189, 61378015, and 11434007), and Program for Changjiang Scholars and Innovative Research Team in Universities of China (Grant No. IRT13076).

  12. Moving towards first science with the St. George recoil separator

    NASA Astrophysics Data System (ADS)

    Meisel, Zachary; Berg, G. P. A.; Gilardy, G.; Moran, M.; Schmitt, J.; Seymour, C.; Stech, E.; Couder, M.

    2015-10-01

    The St. George recoil mass separator has recently been coupled to the 5MV St. Ana accelerator at the University of Notre Dame's Nuclear Science Lab. St. George is a unique tool designed to measure radiative alpha-capture reactions for nuclei up to A = 40 in inverse kinematics in order to directly obtain cross sections required for astrophysical models of stellar and explosive helium burning. Commissioning of St. George is presently taking place with primary beams of hydrogen, helium, and oxygen. In this presentation, results will be shown for the measured energy acceptance of St. George, which compare favorably to COSY results when employing the calculated optimal ion-optical settings. Additionally, future plans will be discussed, such as assessing the angular acceptance of St. George and the re-integration of HiPPO at the separator target position to provide a dense, windowless helium gas-jet target. The material presented in this work is partially supported by the National Science Foundation Grant No. 1419765.

  13. Superconducting Nuclear Recoil Sensor for Directional Dark Matter Detection

    NASA Astrophysics Data System (ADS)

    Junghans, Ann; Baldwin, Kevin; Hehlen, Markus; Lafler, Randy; Loomba, Dinesh; Phan, Nguyen; Weisse-Bernstein, Nina

    The Universe consists of 72% dark energy, 23% dark matter and only 5% of ordinary matter. One of the greatest challenges of the scientific community is to understand the nature of dark matter. Current models suggest that dark matter is made up of slowly moving, weakly interacting massive particles (WIMPs). But detecting WIMPs is challenging, as their expected signals are small and rare compared to the large background that can mimic the signal. The largest and most robust unique signature that sets them apart from other particles is the day-night variation of the directionality of dark matter on Earth. This modulation could be observed with a direction-sensitive detector and hence, would provide an unambiguous signature for the galactic origin of WIMPs. There are many studies underway to attempt to detect WIMPs both directly and indirectly, but solid-state WIMP detectors are widely unexplored although they would present many advantages to prevalent detectors that use large volumes of low pressure gas. We present first results of a novel multi-layered architecture, in which WIMPs would interact primarily with solid layers to produce nuclear recoils that then induce measureable voltage pulses in adjacent superconductor layers. This work was supported by the U.S. Department of Energy through the LANL Laboratory Directed Research and Development Program.

  14. First Measurement of Beam-Recoil Observables Cx and Cz

    SciTech Connect

    R. Bradford; R.A. Schumacher; G. Adams; M.J. Amaryan; P. Ambrozewicz; E. Anciant; M. Anghinolfi; B. Asavapibhop; G. Asryan; G. Audit; H. Avakian; H. Bagdasaryan; N. Baillie; J.P. Ball; N.A. Baltzell; S. Barrow; V. Batourine; M. Battaglieri; K. Beard; I. Bedlinskiy; M. Bektasoglu; M. Bellis; N. Benmouna; B.L. Berman; N. Bianchi; A.S. Biselli; B.E. Bonner; S. Bouchigny; S. Boiarinov; D. Branford; W.J. Briscoe; W.K. Brooks; S. B¨ultmann; V.D. Burkert; C. Butuceanu; J.R. Calarco; S.L. Careccia; D.S. Carman; B. Carnahan; S. Chen; P.L. Cole; A. Coleman; P. Collins; P. Coltharp; D. Cords; † P. Corvisiero; D. Crabb; H. Crannell; V. Crede; J.P. Cummings; R. De Masi; E. De Sanctis; R. De Vita; P.V. Degtyarenko; H. Denizli; L. Dennis; A. Deur; K.V. Dharmawardane; R. Dickson; C. Djalali; G.E. Dodge; J. Donnelly; D. Doughty; P. Dragovitsch; M. Dugger; S. Dytman; O.P. Dzyubak; H. Egiyan; K.S. Egiyan; L. El Fassi; L. Elouadrhiri; A. Empl; P. Eugenio; R. Fatemi; G. Fedotov; G. Feldman; R.J. Feuerbach; T.A. Forest; H. Funsten; M. Garcon; G. Gavalian; G.P. Gilfoyle; K.L. Giovanetti; F.X. Girod; J.T. Goetz; A. Gonenc; R.W. Gothe; K.A. Griffioen; M. Guidal; M. Guillo; N. Guler; L. Guo; V. Gyurjyan; C. Hadjidakis; K. Hafidi; H. Hakobyan; R.S. Hakobyan; J. Hardie; D. Heddle; F.W. Hersman; K. Hicks; I. Hleiqawi; M. Holtrop; J. Hu; M. Huertas; C.E. Hyde-Wright; Y. Ilieva; D.G. Ireland; B.S. Ishkhanov; E.L. Isupov; M.M. Ito; D. Jenkins; H.S. Jo; K. Joo; H.G. Juengst; N. Kalantarians; J.D. Kellie; M. Khandaker; K.Y. Kim; K. Kim; W. Kim; A. Klein; F.J. Klein; M. Klusman; M. Kossov; L.H. Kramer; V. Kubarovsky; J. Kuhn; S.E. Kuhn; S.V. Kuleshov; J. Lachniet; J.M. Laget; J. Langheinrich; D. Lawrence; A.C.S. Lima; K. Livingston; H.Y. Lu; K. Lukashin; M. MacCormick; J.J. Manak; C. Marchand; N. Markov; S. McAleer; B. McKinnon; J.W.C. McNabb; B.A. Mecking; M.D. Mestayer; C.A. Meyer; T. Mibe; K. Mikhailov; M. Mirazita; R. Miskimen; V. Mokeev; K. Moriya; S.A. Morrow; M. Moteabbed; V. Muccifora; J. Mueller; G.S. Mutchler; P. Nadel-Turonski; J. Napolitano; R. Nasseripour; N. Natasha; S. Niccolai; G. Niculescu; I. Niculescu; B.B. Niczyporuk; M.R. Niroula; R.A. Niyazov; M. Nozar; G.V. O’Rielly; M. Osipenko; A.I. Ostrovidov; K. Park; E. Pasyuk; C. Paterson; S.A. Philips; J. Pierce; N. Pivnyuk; D. Pocanic; O. Pogorelko; E. Polli; I. Popa; S. Pozdniakov; B.M. Preedom; J.W. Price; Y. Prok; D. Protopopescu; L.M. Qin; B.P. Quinn; B.A. Raue; G. Riccardi; G. Ricco; M. Ripani; B.G. Ritchie; F. Ronchetti; G. Rosner; P. Rossi; D. Rowntree; P.D. Rubin; F. Sabatie; J. Salamanca; C. Salgado; J.P. Santoro; V. Sapunenko; V.S. Serov; A. Shafi; Y.G. Sharabian; J. Shaw; N.V. Shvedunov; S. Simionatto; A.V. Skabelin; E.S. Smith; L.C. Smith; D.I. Sober; D. Sokhan; M. Spraker; A. Stavinsky; S.S. Stepanyan; S. Stepanyan; B.E. Stokes; P. Stoler; I.I. Strakovsky; S. Strauch; M. Taiuti; S. Taylor; D.J. Tedeschi; U. Thoma; R. Thompson; A. Tkabladze; S. Tkachenko; L. Todor; C. Tur; M. Ungaro; M.F. Vineyard; A.V. Vlassov; K. Wang; D.P. Watts; L.B. Weinstein; H. Weller; D.P. Weygand; M. Williams; E. Wolin; M.H. Wood; A. Yegneswaran; J. Yun; L. Zana; J. Zhang; B. Zhao; and Z.W. Zhao

    2007-03-01

    Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions $\\vec\\gamma + p \\to K^+ + \\vec\\Lambda$ and $\\vec\\gamma + p \\to K^+ + \\vec\\Sigma^0$. The data were obtained using the CLAS detector at Jefferson Lab for center-of-mass energies $W$ between 1.6 and 2.53 GeV, and for $-0.85<\\cos\\theta_{K^+}^{c.m.}< +0.95$. For the $\\Lambda$, the polarization transfer coefficient along the photon momentum axis, $C_z$, was found to be near unity for a wide range of energy and kaon production angles. The associated transverse polarization coefficient, $C_x$, is smaller than $C_z$ by a roughly constant difference of unity. Most significantly, the {\\it total} $\\Lambda$ polarization vector, including the induced polarization $P$, has magnitude consistent with unity at all measured energies and production angles when the beam is fully polarized. For the $\\Sigma^0$ this simple phenomenology does not hold. All existing hadrodynamic models are in poor agreement with these results.

  15. Automation of experiments at Dubna Gas-Filled Recoil Separator

    NASA Astrophysics Data System (ADS)

    Tsyganov, Yu. S.

    2016-01-01

    Approaches to solving the problems of automation of basic processes in long-term experiments in heavy ion beams of the Dubna Gas-Filled Recoil Separator (DGFRS) facility are considered. Approaches in the field of spectrometry, both of rare α decays of superheavy nuclei and those for constructing monitoring systems to provide accident-free experiment running with highly radioactive targets and recording basic parameters of experiment, are described. The specific features of Double Side Silicon Strip Detectors (DSSSDs) are considered, special attention is paid to the role of boundary effects of neighboring p-n transitions in the "active correlations" method. An example of an off-beam experiment attempting to observe Zeno effect is briefly considered. Basic examples for nuclear reactions of complete fusion at 48Ca ion beams of U-400 cyclotron (LNR, JINR) are given. A scenario of development of the "active correlations" method for the case of very high intensity beams of heavy ions at promising accelerators of LNR, JINR, is presented.

  16. Further insights into the proton spin with the new HERMES Recoil Detector

    SciTech Connect

    Vilardi, I.

    2007-11-19

    The HERMES experiment, installed in the 27.5 GeV HERA lepton ring at DESY/Hamburg, is used to study the spin structure of the nucleon. To get information about the orbital angular momentum L{sub q} of quarks, exclusive DIS reactions are investigated. The HERMES Collaboration installed a new Recoil Detector to upgrade the existing spectrometer to improve the study of hard exclusive processes, detecting recoil protons with low momentum. Deeply Virtual Compton Scattering is the main process to be studied. The HERMES Recoil Detector consists of three subcomponents inside a superconducting magnet that provides a longitudinal superconducting magnetic field of 1 Tesla. The Recoil Detector was installed in January 2006 and commissioning started in February. First results from the detector will be presented.

  17. Element-specific recoil loops in Sm-Co/Fe exchange-spring magnets.

    SciTech Connect

    Choi, Y.; Jiang, J. S.; Pearson, J. E.; Bader, S. D.; Liu, J. P.; Materials Science Division; Univ. Texas at Arlington

    2008-04-01

    In two-phase nanocomposite magnets, open recoil loops have shown to be sensitive to interphase interfacial conditions and have been often used to characterize the interphase exchange coupling. Typically, the open recoil loops are attributed to the soft phase volume that is decoupled from the hard phase. Our element-specific magnetic measurements on bilayer Sm-Co/Fe exchange-spring magnets reveal that open recoil loops are present not only in the soft Fe layer but also in the hard Sm-Co layer and that the Fe- and Sm-specific remanence curves are similar to each other. The experimental results and micromagnetic modeling reveal that the observed open recoil loops can originate from the anisotropy variations in the hard Sm-Co layer.

  18. Postinstability models in elasticity

    NASA Technical Reports Server (NTRS)

    Zak, M.

    1984-01-01

    It is demonstrated that the instability caused by the failure of hyperbolicity in elasticity and associated with the problem of unpredictability in classical mechanics expresses the incompleteness of the original model of an elastic medium. The instability as well as the ill-posedness of the Cauchy problem are eliminated by reformulating the original model.

  19. Elastic properties of minerals

    SciTech Connect

    Aleksandrov, K.S.; Prodaivoda, G.T.

    1993-09-01

    Investigations of the elastic properties of the main rock-forming minerals were begun by T.V. Ryzhova and K.S. Aleksandrov over 30 years ago on the initiative of B.P. Belikov. At the time, information on the elasticity of single crystals in general, and especially of minerals, was very scanty. In the surveys of that time there was information on the elasticity of 20 or 30 minerals. These, as a rule, did not include the main rock-forming minerals; silicates were represented only by garnets, quartz, topaz, tourmaline, zircon, beryl, and staurolite, which are often found in nature in the form of large and fairly high-quality crystals. Then and even much later it was still necessary to prove a supposition which now seems obvious: The elastic properties of rocks, and hence the velocities of elastic (seismic) waves in the earth`s crust, are primarily determined by the elastic characteristics of the minerals composing these rocks. Proof of this assertion, with rare exceptions of mono-mineralic rocks (marble, quartzite, etc.) cannot be obtained without information on the elasticities of a sufficiently large number of minerals, primarily framework, layer, and chain silicates which constitute the basis of most rocks. This also served as the starting point and main problem of the undertakings of Aleksandrov, Ryzhova, and Belikov - systematic investigations of the elastic properties of minerals and then of various rocks. 108 refs., 7 tabs.

  20. Elastic limit of silicane.

    PubMed

    Peng, Qing; De, Suvranu

    2014-10-21

    Silicane is a fully hydrogenated silicene-a counterpart of graphene-having promising applications in hydrogen storage with capacities larger than 6 wt%. Knowledge of its elastic limit is critical in its applications as well as tailoring its electronic properties by strain. Here we investigate the mechanical response of silicane to various strains using first-principles calculations based on density functional theory. We illustrate that non-linear elastic behavior is prominent in two-dimensional nanomaterials as opposed to bulk materials. The elastic limits defined by ultimate tensile strains are 0.22, 0.28, and 0.25 along armchair, zigzag, and biaxial directions, respectively, an increase of 29%, 33%, and 24% respectively in reference to silicene. The in-plane stiffness and Poisson ratio are reduced by a factor of 16% and 26%, respectively. However, hydrogenation/dehydrogenation has little effect on its ultimate tensile strengths. We obtained high order elastic constants for a rigorous continuum description of the nonlinear elastic response. The limitation of second, third, fourth, and fifth order elastic constants are in the strain range of 0.02, 0.08, and 0.13, and 0.21, respectively. The pressure effect on the second order elastic constants and Poisson's ratio were predicted from the third order elastic constants. Our results could provide a safe guide for promising applications and strain-engineering the functions and properties of silicane monolayers. PMID:25190587

  1. Investigation on modeling and controability of a magnetorheological gun recoil damper

    NASA Astrophysics Data System (ADS)

    Hu, Hongsheng; Wang, Juan; Wang, Jiong; Qian, Suxiang; Li, Yancheng

    2009-07-01

    Magnetorheological (MR) fluid as a new smart material has done well in the vibration and impact control engineering fields because of its good electromechanical coupling characteristics, preferable dynamic performance and higher sensitivity. And success of MRF has been apparent in many engineering applied fields, such as semi-active suspension, civil engineering, etc. So far, little research has been done about MR damper applied into the weapon system. Its primary purpose of this study is to identify its dynamic performance and controability of the artillery recoil mechanism equipped with MR damper. Firstly, based on the traditional artillery recoil mechanism, a recoil dynamic model is developed in order to obtain an ideal rule between recoil force and its stroke. Then, its effects of recoil resistance on the stability and firing accuracy of artillery are explored. Because MR gun recoil damper under high impact load shows a typical nonlinear character and there exists a shear-thinning phenomenon, to establish an accurate dynamic model has been a seeking aim of its design and application for MR damper under high impact load. Secondly, in this paper, considering its actual bearing load, an inertia factor was introduced to Herschel-Bulkley model, and some factor's effect on damping force are simulated and analyzed by using numerical simulation, including its dynamic performance under different flow coefficients and input currents. Finally, both of tests with the fixed current and different On-Off control algorithms have been done to confirm its controability of MR gun recoil damper under high impact load. Experimental results show its dynamic performances of the large-scale single-ended MR gun recoil damper can be changed by altering the applied currents and it has a good controllability.

  2. As-Al recoil implantation through Si 3N 4 barrier layer

    NASA Astrophysics Data System (ADS)

    Godignon, P.; Morvan, E.; Montserrat, J.; Jordà, X.; Flores, D.; Rebollo, J.

    1999-01-01

    Al recoil implantation have been shown to be a possible alternative to direct Al ion implantation to avoid usual problems linked with Al sources. Poor efficiency of the recoil + annealing process is observed if no barrier or an oxyde screen layers are used. This problem can be solved using a Si 3N 4 screen layer. Then, P-N and N +/P/N structures can be obtained with deep low doped P-well with reduced thermal budget.

  3. Acute stent recoil in the left main coronary artery treated with additional stenting.

    PubMed

    Battikh, Kais; Rihani, Riadh; Lemahieu, Jean Michel

    2003-01-01

    We report a case of acute stent recoil occurring after the stenting of an ostial left main coronary artery lesion. The marked recoil after high-pressure balloon inflation confirmed that the radial force of the first stent was unable to ensure vessel patency. The addition of a second stent provided the necessary support to achieve a good final result. This case illustrates a possible complication of aorto-ostial angioplasty that could be treated with double stenting. PMID:12499528

  4. Proton Nucleus Elastic Scattering Data.

    Energy Science and Technology Software Center (ESTSC)

    1993-08-18

    Version 00 The Proton Nucleus Elastic Scattering Data file PNESD contains the numerical data and the related bibliography for the differential elastic cross sections, polarization and integral nonelastic cross sections for elastic proton-nucleus scattering.

  5. Recoil-range studies of heavy products of multinucleon transfer from /sup 18/O to /sup 245/Cm and /sup 249/Cf

    SciTech Connect

    McFarland, R.M.

    1982-09-01

    Recoil range distributions were measured for alpha and spontaneous fission activities made in the bombardment of /sup 245/Cm and /sup 249/Cf with /sup 18/O from 6.20 MeV/nucleon down to the interaction barrier. The shape of the distributions indicates tht transfers of up to four protons take place via a combination of quasi-elastic (QET) and deep inelastic (DIT) mechanisms, rather than complete fusion-de-excitation (CF) or massive transfer (MT). Angular distributions constructed from recoil range distributions, assuming QET/DIT, indicate that the QET component contributes more significantly to the heavy product residue cross section than the DIT, even though primary cross sections are expected to be higher for DIT than for QET. This may be explained qualitatively as a result of the high excitation energies associated with DIT; the very negative Q/sub gg/ of projectile stripping for these systems combined with the lower expected optimal Q/sub rxn/ of QET compared to DIT can give QET products comparatively low excitation.

  6. On granular elasticity

    PubMed Central

    Sun, Qicheng; Jin, Feng; Wang, Guangqian; Song, Shixiong; Zhang, Guohua

    2015-01-01

    Mesoscopic structures form in dense granular materials due to the self-organisation of the constituent particles. These structures have internal structural degrees of freedom in addition to the translational degree of freedom. The resultant granular elasticity, which exhibits intrinsic variations and inevitable relaxation, is a key quantity that accounts for macroscopic solid- or fluid-like properties and the transitions between them. In this work, we propose a potential energy landscape (PEL) with local stable basins and low elastic energy barriers to analyse the nature of granular elasticity. A function for the elastic energy density is proposed for stable states and is further calibrated with ultrasonic measurements. Fluctuations in the elastic energy due to the evolution of internal structures are proposed to describe a so-called configuration temperature Tc as a counterpart of the classical kinetic granular temperature Tk that is attributed to the translational degrees of freedom. The two granular temperatures are chosen as the state variables, and a fundamental equation is established to develop non-equilibrium thermodynamics for granular materials. Due to the relatively low elastic energy barrier in the PEL, granular elasticity relaxes more under common mechanical loadings, and a simple model based on mean-field theory is developed to account for this behaviour. PMID:25951049

  7. Elastic membranes in confinement

    NASA Astrophysics Data System (ADS)

    Bostwick, Joshua; Miksis, Michael; Davis, Stephen

    2014-11-01

    An elastic membrane stretched between two walls takes a shape defined by its length and the volume of fluid it encloses. Many biological structures, such as cells, mitochondria and DNA, have finer internal structure in which a membrane (or elastic member) is geometrically ``confined'' by another object. We study the shape stability of elastic membranes in a ``confining'' box and introduce repulsive van der Waals forces to prevent the membrane from intersecting the wall. We aim to define the parameter space associated with mitochondria-like deformations. We compare the confined to `unconfined' solutions and show how the structure and stability of the membrane shapes changes with the system parameters.

  8. The structure and micromechanics of elastic tissue

    PubMed Central

    Green, Ellen M.; Mansfield, Jessica C.; Bell, James S.; Winlove, C. Peter

    2014-01-01

    Elastin is a major component of tissues such as lung and blood vessels, and endows them with the long-range elasticity necessary for their physiological functions. Recent research has revealed the complexity of these elastin structures and drawn attention to the existence of extensive networks of fine elastin fibres in tissues such as articular cartilage and the intervertebral disc. Nonlinear microscopy, allowing the visualization of these structures in living tissues, is informing analysis of their mechanical properties. Elastic fibres are complex in composition and structure containing, in addition to elastin, an array of microfibrillar proteins, principally fibrillin. Raman microspectrometry and X-ray scattering have provided new insights into the mechanisms of elasticity of the individual component proteins at the molecular and fibrillar levels, but more remains to be done in understanding their mechanical interactions in composite matrices. Elastic tissue is one of the most stable components of the extracellular matrix, but impaired mechanical function is associated with ageing and diseases such as atherosclerosis and diabetes. Efforts to understand these associations through studying the effects of processes such as calcium and lipid binding and glycation on the mechanical properties of elastin preparations in vitro have produced a confusing picture, and further efforts are required to determine the molecular basis of such effects. PMID:24748954

  9. Measurement of Scintillation and Ionization Yield and Scintillation Pulse Shape from Nuclear Recoils in Liquid Argon

    SciTech Connect

    Cao, H.

    2015-05-26

    We have measured the scintillation and ionization yield of recoiling nuclei in liquid argon as a function of applied electric field by exposing a dual-phase liquid argon time projection chamber (LAr-TPC) to a low energy pulsed narrow band neutron beam produced at the Notre Dame Institute for Structure and Nuclear Astrophysics. Liquid scintillation counters were arranged to detect and identify neutrons scattered in the TPC and to select the energy of the recoiling nuclei. We also report measurements of the scintillation yields for nuclear recoils with energies from 10.3 to 57.3 keV and for median applied electric fields from 0 to 970 V/cm. For the ionization yields, we report measurements from 16.9 to 57.3 keV and for electric fields from 96.4 to 486 V/cm. Furthermore, we report the observation of an anticorrelation between scintillation and ionization from nuclear recoils, which is similar to the anticorrelation between scintillation and ionization from electron recoils. Assuming that the energy loss partitions into excitons and ion pairs from 83mKr internal conversion electrons is comparable to that from 207Bi conversion electrons, we obtained the numbers of excitons (Nex) and ion pairs (Ni) and their ratio (Nex/Ni) produced by nuclear recoils from 16.9 to 57.3 keV. Motivated by arguments suggesting direction sensitivity in LAr-TPC signals due to columnar recombination, a comparison of the light and charge yield of recoils parallel and perpendicular to the applied electric field is presented for the first time.

  10. Measurement of Scintillation and Ionization Yield and Scintillation Pulse Shape from Nuclear Recoils in Liquid Argon

    DOE PAGESBeta

    Cao, H.

    2015-05-26

    We have measured the scintillation and ionization yield of recoiling nuclei in liquid argon as a function of applied electric field by exposing a dual-phase liquid argon time projection chamber (LAr-TPC) to a low energy pulsed narrow band neutron beam produced at the Notre Dame Institute for Structure and Nuclear Astrophysics. Liquid scintillation counters were arranged to detect and identify neutrons scattered in the TPC and to select the energy of the recoiling nuclei. We also report measurements of the scintillation yields for nuclear recoils with energies from 10.3 to 57.3 keV and for median applied electric fields from 0more » to 970 V/cm. For the ionization yields, we report measurements from 16.9 to 57.3 keV and for electric fields from 96.4 to 486 V/cm. Furthermore, we report the observation of an anticorrelation between scintillation and ionization from nuclear recoils, which is similar to the anticorrelation between scintillation and ionization from electron recoils. Assuming that the energy loss partitions into excitons and ion pairs from 83mKr internal conversion electrons is comparable to that from 207Bi conversion electrons, we obtained the numbers of excitons (Nex) and ion pairs (Ni) and their ratio (Nex/Ni) produced by nuclear recoils from 16.9 to 57.3 keV. Motivated by arguments suggesting direction sensitivity in LAr-TPC signals due to columnar recombination, a comparison of the light and charge yield of recoils parallel and perpendicular to the applied electric field is presented for the first time.« less

  11. Mechanism of Resilin Elasticity

    PubMed Central

    Qin, Guokui; Hu, Xiao; Cebe, Peggy; Kaplan, David L.

    2012-01-01

    Resilin is critical in the flight and jumping systems of insects as a polymeric rubber-like protein with outstanding elasticity. However, insight into the underlying molecular mechanisms responsible for resilin elasticity remains undefined. Here we report the structure and function of resilin from Drosophila CG15920. A reversible beta-turn transition was identified in the peptide encoded by exon III and for full length resilin during energy input and release, features that correlate to the rapid deformation of resilin during functions in vivo. Micellar structures and nano-porous patterns formed after beta-turn structures were present via changes in either the thermal or mechanical inputs. A model is proposed to explain the super elasticity and energy conversion mechanisms of resilin, providing important insight into structure-function relationships for this protein. Further, this model offers a view of elastomeric proteins in general where beta-turn related structures serve as fundamental units of the structure and elasticity. PMID:22893127

  12. Elastic proteins and elastomeric protein alloys.

    PubMed

    Aghaei-Ghareh-Bolagh, Behnaz; Mithieux, Suzanne M; Weiss, Anthony S

    2016-06-01

    The elastomeric proteins elastin and resilin have been used extensively in the fabrication of biomaterials for tissue engineering applications due to their unique mechanical and biological properties. Tropoelastin is the soluble monomer component of elastin. Tropoelastin and resilin are both highly elastic with high resilience, substantial extensibility, high durability and low energy loss, which makes them excellent candidates for the fabrication of elastic tissues that demand regular and repetitive movement like the skin, lung, blood vessels, muscles and vocal folds. Combinations of these proteins with silk fibroin further enhance their biomechanical and biological properties leading to a new class of protein alloy materials with versatile properties. In this review, the properties of tropoelastin-based and resilin-based biomaterials with and without silk are described in concert with examples of their applications in tissue engineering. PMID:26780495

  13. Lung transplant

    MedlinePlus

    ... nih.gov/pubmed/20675678 . Kotloff RM, Keshavjee S. Lung transplantation. In: Broaddus VC, Mason RJ, Ernst MD, et ... 58. Solomon M, Grasemann H, Keshavjee S. Pediatric lung transplantation. Pediatr Clin North Am . 2010; 57(2):375- ...

  14. Lung Cancer

    MedlinePlus

    Lung cancer is one of the most common cancers in the world. It is a leading cause of ... in the United States. Cigarette smoking causes most lung cancers. The more cigarettes you smoke per day and ...

  15. Lung transplant

    MedlinePlus

    ... diseases that may require a lung transplant are: Cystic fibrosis Damage to the arteries of the lung because ... BC; Clinical Practice Guidelines for Pulmonary Therapies Committee; ... Therapies Committee. Cystic fibrosis pulmonary guidelines: ...

  16. Lung surgery

    MedlinePlus

    ... Pneumonectomy; Lobectomy; Lung biopsy; Thoracoscopy; Video-assisted thoracoscopic surgery; VATS ... You will have general anesthesia before surgery. You will be asleep and unable to feel pain. Two common ways to do surgery on your lungs are thoracotomy and video- ...

  17. Analytic Intermodel Consistent Modeling of Volumetric Human Lung Dynamics.

    PubMed

    Ilegbusi, Olusegun; Seyfi, Behnaz; Neylon, John; Santhanam, Anand P

    2015-10-01

    Human lung undergoes breathing-induced deformation in the form of inhalation and exhalation. Modeling the dynamics is numerically complicated by the lack of information on lung elastic behavior and fluid-structure interactions between air and the tissue. A mathematical method is developed to integrate deformation results from a deformable image registration (DIR) and physics-based modeling approaches in order to represent consistent volumetric lung dynamics. The computational fluid dynamics (CFD) simulation assumes the lung is a poro-elastic medium with spatially distributed elastic property. Simulation is performed on a 3D lung geometry reconstructed from four-dimensional computed tomography (4DCT) dataset of a human subject. The heterogeneous Young's modulus (YM) is estimated from a linear elastic deformation model with the same lung geometry and 4D lung DIR. The deformation obtained from the CFD is then coupled with the displacement obtained from the 4D lung DIR by means of the Tikhonov regularization (TR) algorithm. The numerical results include 4DCT registration, CFD, and optimal displacement data which collectively provide consistent estimate of the volumetric lung dynamics. The fusion method is validated by comparing the optimal displacement with the results obtained from the 4DCT registration. PMID:26292034

  18. Deflation of elastic surfaces

    NASA Astrophysics Data System (ADS)

    Quilliet, Catherine; Quemeneur, François; Marmottant, Philippe; Imhof, Arnout; Pépin-Donat, Brigitte; van Blaaderen, Alfons

    2010-03-01

    The deflation of elastic spherical surfaces has been numerically investigated, and show very different types of deformations according the range of elastic parameters, some of them being quantitatively explained through simple calculations. This allows to retrieve various shapes observed on hollow shells (from colloidal to centimeter scale), on lipid vesicles, or on some biological objects. The extension of this process to other geometries allows to modelize vegetal objects such as the ultrafast trap of carnivorous plants.

  19. Quantitative analysis of the energy distributions of electrons backscattered elastically from polyethylene

    NASA Astrophysics Data System (ADS)

    Tőkési, K.; Varga, D.; Berényi, Z.

    2015-07-01

    We present results of theoretical and experimental studies of the spectra of electrons backscattered elastically from polyethylene in the primary energy range between 1 and 5 keV. The experiments were performed using a high energy resolution electron spectroscopy. The theoretical interpretation is based on a Monte Carlo simulation of the recoil and Doppler effects. The separation between the carbon and hydrogen peak in the energy distributions is shown as a function of the primary electron energy. The simulations give many partial distributions separately, depending on the number of elastic scatterings (single, and multiple scatterings of different types). We show our results for intensity ratios, peak shifts and broadenings. We also present detailed analytical calculations for the main parameters of a single scattering. Finally, we present a qualitative comparison with the experimental data. We find our resulting energy distribution of elastically scattered electrons to be in good agreement with our measurements.

  20. Elastic Collisions and Gravity

    NASA Astrophysics Data System (ADS)

    Ball, Steven

    2009-04-01

    Elastic collisions are fascinating demonstrations of conservation principles. The mediating force must be conservative in an elastic collision. Truly elastic collisions take place only when the objects in collision do not touch, e.g. magnetic bumpers on low friction carts. This requires that we define a collision as a momentum transfer. Elastic collisions in 1-D can be solved in general and the implications are quite remarkable. For example, a heavy object moving initially towards a light object followed by an elastic collision results in a final velocity of the light object greater than either initial velocity. This is easily demonstrated with low friction carts. Gravitational elastic collisions involving a light spacecraft and an extremely massive body like a moon or planet can be approximated as 1-D collisions, such as the ``free return'' trajectory of Apollo 13 around the moon. The most fascinating gravitational collisions involve the gravitational slingshot effect used to boost spacecraft velocities. The maximum gravitational slingshot effect occurs when approaching a nearly 1-D collision, revealing that the spacecraft can be boosted to greater than twice the planet velocity, enabling the spacecraft to travel much further away from the Sun.

  1. EFFECT OF LASER LIGHT ON MATTER. LASER PLASMAS: Recoil momentum at a solid surface during developed laser ablation

    NASA Astrophysics Data System (ADS)

    Kuznetsov, L. I.

    1993-12-01

    The recoil momentum from a laser light pulse in the intensity range 105-107 W/cm2 is experimentally investigated for dielectric and metallic targets as a function of the pressure of the surrounding medium and angle of illumination. An equation with empirical coefficients is obtained for the recoil momentum of illuminated targets. Effects of the screening properties of the erosion jet and the back pressure on the recoil momentum are analyzed as the external pressure is varied.

  2. Measurement of the proton form factors ratio G{sub E}/G{sub M} to Q{sup 2} = 5.6 GeV{sup 2} by recoil polarimetry

    SciTech Connect

    Olivier Gayou

    2002-04-01

    In this thesis, we present the results of the experiment E99-007, which measured the ratio of the electric to magnetic form factors of the proton to the four momentum transfer square Q{sup 2} = 5.6 GeV{sup 2}, by recoil polarimetry. Data were taken in 2000 at the Thomas Jefferson National Accelerator Facility in Virginia, USA. A 4.6 GeV polarized electron beam was scattered off a cryogenic hydrogen target. The polarization of the recoil proton was measured in the Focal Plane Polarimeter, located after one of the two High Resolution Spectrometers in the hall. The ratio of the transverse to longitudinal components of the recoil proton polarization is proportional to the ratio of the form factors. Elastic events were selected by detecting the scattered electron in a large acceptance lead-glass calorimeter. The main result of this experiment is the linear decrease of the form factor ratio with increasing Q{sup 2}, corresponding to different spatial distributions of the electric charge and the magnetization. Numerous theoretical calculations show that relativistic effects, such as mixing of spin states due to Lorentz boosts, are important to account for the observed data in this critical intermediate kinematic region.

  3. Anomalous bubble propagation in elastic tubes

    NASA Astrophysics Data System (ADS)

    Heap, Alexandra; Juel, Anne

    2008-08-01

    Airway reopening is an important physiological event, as exemplified by the first breath of an infant that inflates highly collapsed airways by driving a finger of air through its fluid-filled lungs. Whereas fundamental models of airway reopening predict the steady propagation of only one type of bubble with a characteristic rounded tip, our experiments reveal a surprising selection of novel bubbles with counterintuitive shapes that reopen strongly collapsed, liquid-filled elastic tubes. Our multiple bubbles are associated with a discontinuous relationship between bubble pressure and speed that sets exciting challenges for modelers.

  4. Effect of gravity and posture on lung mechanics.

    PubMed

    Bettinelli, D; Kays, C; Bailliart, O; Capderou, A; Techoueyres, P; Lachaud, J L; Vaïda, P; Miserocchi, G

    2002-12-01

    The volume-pressure relationship of the lung was studied in six subjects on changing the gravity vector during parabolic flights and body posture. Lung recoil pressure decreased by approximately 2.7 cmH(2)O going from 1 to 0 vertical acceleration (G(z)), whereas it increased by approximately 3.5 cmH(2)O in 30 degrees tilted head-up and supine postures. No substantial change was found going from 1 to 1.8 G(z). Matching the changes in volume-pressure relationships of the lung and chest wall (previous data), results in a decrease in functional respiratory capacity of approximately 580 ml at 0 G(z) relative to 1 G(z) and of approximately 1,200 ml going to supine posture. Microgravity causes a decrease in lung and chest wall recoil pressures as it removes most of the distortion of lung parenchyma and thorax induced by changing gravity field and/or posture. Hypergravity does not greatly affect respiratory mechanics, suggesting that mechanical distortion is close to maximum already at 1 G(z). The end-expiratory volume during quiet breathing corresponds to the mechanical functional residual capacity in each condition. PMID:12391116

  5. Imprints of recoiling massive black holes on the hot gas of early-type galaxies

    NASA Astrophysics Data System (ADS)

    Devecchi, B.; Rasia, E.; Dotti, M.; Volonteri, M.; Colpi, M.

    2009-04-01

    Anisotropic gravitational radiation from a coalescing black hole (BH) binary is known to impart recoil velocities of up to ~1000kms-1 to the remnant BH. In this context, we study the motion of a recoiling BH inside a galaxy modelled as a Hernquist sphere, and the signature that the hole imprints on the hot gas, using N-body/smoothed particle hydrodynamics simulations. Ejection of the BH results in a sudden expansion of the gas ending with the formation of a gaseous core, similarly to what is seen for the stars. A cometary tail of particles bound to the BH is initially released along its trail. As the BH moves on a return orbit, a nearly spherical swarm of hot gaseous particles forms at every apocentre: this feature can live up to ~108 years. If the recoil velocity exceeds the sound speed initially, the BH shocks the gas in the form of a Mach cone in density near each supersonic pericentric passage. We find that the X-ray fingerprint of a recoiling BH can be detected in Chandra X-ray maps out to a distance of Virgo. For exceptionally massive BHs, the Mach cone and the wakes can be observed out to a few hundred of milliparsec. The detection of the Mach cone is of twofold importance as it can be a probe of high-velocity recoils, and an assessment of the scatter of the MBH - Mbulge relation at large BH masses.

  6. Elasticity of plagioclase feldspars

    NASA Astrophysics Data System (ADS)

    Brown, J. Michael; Angel, Ross J.; Ross, Nancy L.

    2016-02-01

    Elastic properties are reported for eight plagioclase feldspars that span compositions from albite (NaSi3AlO8) to anorthite (CaSi2Al2O8). Surface acoustic wave velocities measured using Impulsive Stimulated Light Scattering and compliance sums from high-pressure X-ray compression studies accurately determine all 21 components of the elasticity tensor for these triclinic minerals. The overall pattern of elasticity and the changes in individual elastic components with composition can be rationalized on the basis of the evolution of crystal structures and chemistry across this solid-solution join. All plagioclase feldspars have high elastic anisotropy; a* (the direction perpendicular to the b and c axes) is the softest direction by a factor of 3 in albite. From albite to anorthite the stiffness of this direction undergoes the greatest change, increasing twofold. Small discontinuities in the elastic components, inferred to occur between the three plagioclase phases with distinct symmetry (C1>¯, I1>¯, and P1>¯), appear consistent with the nature of the underlying conformation of the framework-linked tetrahedra and the associated structural changes. Measured body wave velocities of plagioclase-rich rocks, reported over the last five decades, are consistent with calculated Hill-averaged velocities using the current moduli. This confirms long-standing speculation that previously reported elastic moduli for plagioclase feldspars are systematically in error. The current results provide greater assurance that the seismic structure of the middle and lower crusts can be accurately estimated on the basis of specified mineral modes, chemistry, and fabric.

  7. What Is Lung Cancer?

    MedlinePlus

    ... starts in the lungs, it is called lung cancer. Lung cancer begins in the lungs and may spread ... lung cancer. For more information, visit the National Cancer Institute’s Lung Cancer. Previous Basic Information Basic Information Basic Information ...

  8. Lung Organogenesis

    PubMed Central

    Warburton, David; El-Hashash, Ahmed; Carraro, Gianni; Tiozzo, Caterina; Sala, Frederic; Rogers, Orquidea; De Langhe, Stijn; Kemp, Paul J.; Riccardi, Daniela; Torday, John; Bellusci, Saverio; Shi, Wei; Lubkin, Sharon R; Jesudason, Edwin

    2011-01-01

    Developmental lung biology is a field that has the potential for significant human impact: lung disease at the extremes of age continues to cause major morbidity and mortality worldwide. Understanding how the lung develops holds the promise that investigators can use this knowledge to aid lung repair and regeneration. In the decade since the “molecular embryology” of the lung was first comprehensively reviewed, new challenges have emerged—and it is on these that we focus the current review. Firstly, there is a critical need to understand the progenitor cell biology of the lung in order to exploit the potential of stem cells for the treatment of lung disease. Secondly, the current familiar descriptions of lung morphogenesis governed by growth and transcription factors need to be elaborated upon with the reinclusion and reconsideration of other factors, such as mechanics, in lung growth. Thirdly, efforts to parse the finer detail of lung bud signaling may need to be combined with broader consideration of overarching mechanisms that may be therapeutically easier to target: in this arena, we advance the proposal that looking at the lung in general (and branching in particular) in terms of clocks may yield unexpected benefits. PMID:20691848

  9. Experimental Concept for a Precision Measurement of Nuclear Recoil Ionization Yields for Low Mass WIMP Searches

    NASA Astrophysics Data System (ADS)

    Saab, T.; Figueroa-Feliciano, E.

    2016-07-01

    Understanding the response of dark matter detectors at the lowest recoil energies is important for correctly interpreting data from current experiments or predicting the sensitivity of future experiments to low mass weakly interacting massive particles. In particular, the ionization yield is essential for determining the correct recoil energy of candidate nuclear recoil events; however, few measurements in cryogenic crystals exist below 1 keV. Using the voltage-assisted calorimetric ionization detection technique with a mono-energetic neutron source, we show that it is possible to determine the ionization yield in cryogenic crystals down to an energy to 100 eV. This measurement will also determine the statistics of ionization production at these low energies.

  10. Recoiling black holes: prospects for detection and implications of spin alignment

    NASA Astrophysics Data System (ADS)

    Blecha, Laura; Sijacki, Debora; Kelley, Luke Zoltan; Torrey, Paul; Vogelsberger, Mark; Nelson, Dylan; Springel, Volker; Snyder, Gregory; Hernquist, Lars

    2016-02-01

    Supermassive black hole (BH) mergers produce powerful gravitational wave emission. Asymmetry in this emission imparts a recoil kick to the merged BH, which can eject the BH from its host galaxy altogether. Recoiling BHs could be observed as offset active galactic nuclei (AGN). Several candidates have been identified, but systematic searches have been hampered by large uncertainties regarding their observability. By extracting merging BHs and host galaxy properties from the Illustris cosmological simulations, we have developed a comprehensive model for recoiling AGN. Here, for the first time, we model the effects of BH spin alignment and recoil dynamics based on the gas richness of host galaxies. We predict that if BH spins are not highly aligned, seeing-limited observations could resolve offset AGN, making them promising targets for all-sky surveys. For randomly oriented spins, ≲ 10 spatially offset AGN may be detectable in Hubble Space Telescope-Cosmological Evolution Survey, and >103 could be found with the Panoramic Survey Telescope & Rapid Response System (Pan-STARRS), the Large Synoptic Survey Telescope (LSST), Euclid, and the Wide-Field Infrared Survey Telescope (WFIRST). Nearly a thousand velocity offset AGN are predicted within the Sloan Digital Sky Survey (SDSS) footprint; the rarity of large broad-line offsets among SDSS quasars is likely due in part to selection effects but suggests that spin alignment plays a role in suppressing recoils. None the less, in our most physically motivated model where alignment occurs only in gas-rich mergers, hundreds of offset AGN should be found in all-sky surveys. Our findings strongly motivate a dedicated search for recoiling AGN.

  11. Recoil polarization and beam-recoil double polarization measurement of eta electroproduction on the proton in the region of the S11(1535) resonance.

    PubMed

    Merkel, H; Achenbach, P; Ayerbe Gayoso, C; Bernauer, J C; Böhm, R; Bosnar, D; Cheymol, B; Distler, M O; Doria, L; Fonvieille, H; Friedrich, J; Janssens, P; Makek, M; Müller, U; Nungesser, L; Pochodzalla, J; Potokar, M; Sánchez Majos, S; Schlimme, B S; Sirca, S; Tiator, L; Walcher, Th; Weinriefer, M

    2007-09-28

    The beam-recoil double polarization P(x')(h) and P(z')(h) and the recoil polarization P(y') were measured for the first time for the p(e,e'p)eta reaction at a four-momentum transfer of Q(2) = 0.1 GeV(2)/c(2) and a center of mass production angle of theta = 120 degrees at the Mainz Microtron MAMI-C. With a center of mass energy range of 1500 MeV

  12. Radiation Recoil Effects on the Dynamical Evolution of Asteroids

    NASA Astrophysics Data System (ADS)

    Cotto-Figueroa, Desiree

    The Yarkovsky effect is a radiation recoil force that results in a semimajor axis drift in the orbit that can cause Main Belt asteroids to be delivered to powerful resonances from which they could be transported to Earth-crossing orbits. This force depends on the spin state of the object, which is modified by the YORP effect, a variation of the Yarkovsky effect that results in a torque that changes the spin rate and the obliquity. Extensive analyses of the basic behavior of the YORP effect have been previously conducted in the context of the classical spin state evolution of rigid bodies (YORP cycle). However, the YORP effect has an extreme sensitivity to the topography of the asteroids and a minor change in the shape of an aggregate asteroid can stochastically change the YORP torques. Here we present the results of the first simulations that self-consistently model the YORP effect on the spin states of dynamically evolving aggregates. For these simulations we have developed several algorithms and combined them with two codes, TACO and pkdgrav. TACO is a thermophysical asteroid code that models the surface of an asteroid using a triangular facet representation and which can compute the YORP torques. The code pkdgrav is a cosmological N-body tree code modified to simulate the dynamical evolution of asteroids represented as aggregates of spheres using gravity and collisions. The continuous changes in the shape of an aggregate result in a different evolution of the YORP torques and therefore aggregates do not evolve through the YORP cycle as a rigid body would. Instead of having a spin evolution ruled by long periods of rotational acceleration and deceleration as predicted by the classical YORP cycle, the YORP effect is self-limiting and stochastic on aggregate asteroids. We provide a statistical description of the spin state evolution which lays out the foundation for new simulations of a coupled Yarkovsky/YORP evolution. Both self-limiting YORP and to a lesser

  13. Quantum Critical Elasticity.

    PubMed

    Zacharias, Mario; Paul, Indranil; Garst, Markus

    2015-07-10

    We discuss elastic instabilities of the atomic crystal lattice at zero temperature. Because of long-range shear forces of the solid, at such transitions the phonon velocities vanish, if at all, only along certain crystallographic directions, and, consequently, the critical phonon fluctuations are suppressed to a lower dimensional manifold and governed by a Gaussian fixed point. In the case of symmetry-breaking elastic transitions, a characteristic critical phonon thermodynamics arises that is found, e.g., to violate Debye's T(3) law for the specific heat. We point out that quantum critical elasticity is triggered whenever a critical soft mode couples linearly to the strain tensor. In particular, this is relevant for the electronic Ising-nematic quantum phase transition in a tetragonal crystal as discussed in the context of certain cuprates, ruthenates, and iron-based superconductors. PMID:26207483

  14. Elastic properties of HMX.

    SciTech Connect

    Sewell, T. D.; Bedrov, D.; Menikoff, Ralph; Smith, G. D.

    2001-01-01

    Atomistic molecular dynamics simulations have been used to calculate isothermal elastic properties for {beta}-, {alpha}-, and {delta}-HMX. The complete elastic tensor for each polymorph was determined at room temperature and pressure via analysis of microscopic strain fluctuations using formalism due to Rahman and Parrinello [J. Chem. Phys. 76,2662 (1982)]. Additionally, the isothermal compression curve was computed for {beta}-HMX for 0 {le} p {le} 10.6 GPa; the bulk modulus K and its pressure derivative K{prime} were obtained from two fitting forms employed previously in experimental studies of the {beta}-HMX equation of state. Overall, the results indicate good agreement between the bulk modulus predicted from the measured and calculated compression curves. The bulk modulus determined directly from the elastic tensor of {beta}-HMX is in significant disagreement with the compression curve-based results. The explanation for this discrepancy is an area of current research.

  15. Quantum Critical Elasticity

    NASA Astrophysics Data System (ADS)

    Zacharias, Mario; Paul, Indranil; Garst, Markus

    2015-07-01

    We discuss elastic instabilities of the atomic crystal lattice at zero temperature. Because of long-range shear forces of the solid, at such transitions the phonon velocities vanish, if at all, only along certain crystallographic directions, and, consequently, the critical phonon fluctuations are suppressed to a lower dimensional manifold and governed by a Gaussian fixed point. In the case of symmetry-breaking elastic transitions, a characteristic critical phonon thermodynamics arises that is found, e.g., to violate Debye's T3 law for the specific heat. We point out that quantum critical elasticity is triggered whenever a critical soft mode couples linearly to the strain tensor. In particular, this is relevant for the electronic Ising-nematic quantum phase transition in a tetragonal crystal as discussed in the context of certain cuprates, ruthenates, and iron-based superconductors.

  16. Mechanics of elastic networks

    PubMed Central

    Norris, Andrew N.

    2014-01-01

    We consider a periodic lattice structure in d=2 or 3 dimensions with unit cell comprising Z thin elastic members emanating from a similarly situated central node. A general theoretical approach provides an algebraic formula for the effective elasticity of such frameworks. The method yields the effective cubic elastic constants for three-dimensional space-filling lattices with Z=4, 6, 8, 12 and 14, the last being the ‘stiffest’ lattice proposed by Gurtner & Durand (Gurtner & Durand 2014 Proc. R. Soc. A 470, 20130611. (doi:10.1098/rspa.2013.0611)). The analytical expressions provide explicit formulae for the effective properties of pentamode materials, both isotropic and anisotropic, obtained from the general formulation in the stretch-dominated limit for Z=d+1. PMID:25484608

  17. Elastic membranes in confinement.

    PubMed

    Bostwick, J B; Miksis, M J; Davis, S H

    2016-07-01

    An elastic membrane stretched between two walls takes a shape defined by its length and the volume of fluid it encloses. Many biological structures, such as cells, mitochondria and coiled DNA, have fine internal structure in which a membrane (or elastic member) is geometrically 'confined' by another object. Here, the two-dimensional shape of an elastic membrane in a 'confining' box is studied by introducing a repulsive confinement pressure that prevents the membrane from intersecting the wall. The stage is set by contrasting confined and unconfined solutions. Continuation methods are then used to compute response diagrams, from which we identify the particular membrane mechanics that generate mitochondria-like shapes. Large confinement pressures yield complex response diagrams with secondary bifurcations and multiple turning points where modal identities may change. Regions in parameter space where such behaviour occurs are then mapped. PMID:27440257

  18. Elastic constants of calcite

    USGS Publications Warehouse

    Peselnick, L.; Robie, R.A.

    1962-01-01

    The recent measurements of the elastic constants of calcite by Reddy and Subrahmanyam (1960) disagree with the values obtained independently by Voigt (1910) and Bhimasenachar (1945). The present authors, using an ultrasonic pulse technique at 3 Mc and 25??C, determined the elastic constants of calcite using the exact equations governing the wave velocities in the single crystal. The results are C11=13.7, C33=8.11, C44=3.50, C12=4.82, C13=5.68, and C14=-2.00, in units of 1011 dyncm2. Independent checks of several of the elastic constants were made employing other directions and polarizations of the wave velocities. With the exception of C13, these values substantially agree with the data of Voigt and Bhimasenachar. ?? 1962 The American Institute of Physics.

  19. Development of the RAON Recoil Spectrometer (KOBRA) and Its Applications for Nuclear Astrophysics

    NASA Astrophysics Data System (ADS)

    Moon, Jun Young; Park, Junesic; Cheoul Yun, Chong; Kwon, Young Kwan; Komatsubara, Tetsuro; Hashimoto, Takashi; Tshoo, Kyoungho; Lee, Kwangbok; Jung, In-IL; Kim, Yong Hak; Kim, Yong-Kyun

    KOBRA (KOrea Broad acceptance Recoil spectrometer and Apparatus), a new generation recoil spectrometer, has been designed at the Korean heavy-ion accelerator facility, so called RAON. It will allow many nuclear scientists to explore so-far hard but very interesting questions relevant to low-energy nuclear physics. Especially, in nuclear astrophysics where the unstable, short-lived nuclei are usually involved and the high background rejection power is required, its high performance will come into significantly important role. As a particular case to see its capability, in this article, calculational results of 12C(α, γ)16O reaction which was studied with the COSY-INFINITY is presented.

  20. Discrimination of nuclear and electronic recoil events using plasma effect in germanium detectors

    NASA Astrophysics Data System (ADS)

    Wei, W.-Z.; Liu, J.; Mei, D.-M.

    2016-07-01

    We report a new method of using the plasma time difference, which results from the plasma effect, between the nuclear and electronic recoil events in high-purity germanium detectors to distinguish these two types of events in the search for rare physics processes. The physics mechanism of the plasma effect is discussed in detail. A numerical model is developed to calculate the plasma time for nuclear and electronic recoils at various energies in germanium detectors. It can be shown that under certain conditions the plasma time difference is large enough to be observable. The experimental aspects in realizing such a discrimination in germanium detectors is discussed.

  1. A model of ventilation of the healthy human lung.

    PubMed

    Steimle, K L; Mogensen, M L; Karbing, D S; Bernardino de la Serna, J; Andreassen, S

    2011-02-01

    This paper presents a model of the lung mechanics which simulates the pulmonary alveolar ventilation. The model includes aspects of: the alveolar geometry; pressure due to the chest wall; pressure due to surface tension determined by surfactant activity; pressure due to lung tissue elasticity; and pressure due to the hydrostatic effects of the lung tissue and blood. The cross-sectional area of the lungs in the supine position derived from computed tomography is used to construct a horizontally layered model, which simulates heterogeneous ventilation distribution from the non-dependent to the dependent layers of the lungs. The model is in agreement with experimentally measured hysteresis of the pressure-volume curve of the lungs, static lung compliance, changes in lung depth during breathing and density distributions at total lung capacity (TLC) and residual volume (RV). In the dependent layers of the lungs, alveolar collapse may occur at RV, depending on the assumptions concerning lung tissue elasticity at very low alveolar volumes. The model simulations showed that ventilation increased with depth in the lungs, although not as pronounced as observed experimentally. The model simulates alveolar ventilation including all of the mentioned components of the respiratory system and to be validated against all the above mentioned experimental data. PMID:20655612

  2. Coiling of Elastic Ropes

    NASA Astrophysics Data System (ADS)

    Habibi, M.; Ribe, N. M.; Bonn, Daniel

    2007-10-01

    A rope falling onto a solid surface typically forms a series of regular coils. Here, we study this phenomenon using laboratory experiments (with cotton threads and softened spaghetti) and an asymptotic “slender-rope” numerical model. The excellent agreement between the two with no adjustable parameters allows us to determine a complete phase diagram for elastic coiling comprising three basic regimes involving different force balances (elastic, gravitational, and inertial) together with resonant “whirling string” and “whirling shaft” eigenmodes in the inertial regime.

  3. Farmer's lung

    PubMed Central

    Hapke, E. J.; Seal, R. M. E.; Thomas, G. O.; Hayes, M.; Meek, J. C.

    1968-01-01

    In assessing patients suffering from farmer's lung, the acute stage must be distinguished from the chronic stage of the disease. The conspicuous radiographic signs in the acute farmer's lung episode and the often dramatic clearing make an important contribution to the diagnosis. The radiographic changes in chronic farmer's lung are not specific and cover a wide range of appearances. Even minor nodular changes are significant. Farmer's lung, acute and chronic, is not a disease predominantly characterized by a defect in gas exchange. During the acute illness the reduction in diffusing capacity is often accompanied by a decrease in lung volumes; the pulmonary function profile of the chronic stage is variable. In only a relatively small proportion of chronic farmer's lung patients does a defect in gas exchange predominate, and in some it may be manifest only during exercise. Airway obstruction is a feature of chronic farmer's lung. In chronic farmer's lung patients discrepancies between the severity of complaints and results of pulmonary function tests are not infrequent. In some patients with considerable disability conventional pulmonary function studies may demonstrate little or no impairment of the functions measured. In patients suffering from an acute farmer's lung episode, serological tests should be positive, possibly in high titre. In the chronic stage of the disease the chance of finding positive serology in a patient diminishes with the length of time elapsed since the last acute episode. The period of serological transition appears to be the third year. Images PMID:4971361

  4. Lung cancer.

    PubMed

    Akhurst, Tim; MacManus, Michael; Hicks, Rodney J

    2015-04-01

    (18)F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) plays a key role in the evaluation of undiagnosed lung nodules, when primary lung cancer is strongly suspected, or when it has already been diagnosed by other techniques. Although technical factors may compromise characterization of small or highly mobile lesions, lesions without apparent FDG uptake can generally be safely observed, whereas FDG-avid lung nodules almost always need further evaluation. FDG-PET/CT is now the primary staging imaging modality for patients with lung cancer who are being considered for curative therapy with either surgery or definitive radiation therapy. PMID:25829084

  5. The Law of Elasticity

    ERIC Educational Resources Information Center

    Cocco, Alberto; Masin, Sergio Cesare

    2010-01-01

    Participants estimated the imagined elongation of a spring while they were imagining that a load was stretching the spring. This elongation turned out to be a multiplicative function of spring length and load weight--a cognitive law analogous to Hooke's law of elasticity. Participants also estimated the total imagined elongation of springs joined…

  6. Hydrodynamic Elastic Magneto Plastic

    Energy Science and Technology Software Center (ESTSC)

    1985-02-01

    The HEMP code solves the conservation equations of two-dimensional elastic-plastic flow, in plane x-y coordinates or in cylindrical symmetry around the x-axis. Provisions for calculation of fixed boundaries, free surfaces, pistons, and boundary slide planes have been included, along with other special conditions.

  7. Elastic and Inelastic Collisions

    ERIC Educational Resources Information Center

    Gluck, Paul

    2010-01-01

    There have been two articles in this journal that described a pair of collision carts used to demonstrate vividly the difference between elastic and inelastic collisions. One cart had a series of washers that were mounted rigidly on a rigid wooden framework, the other had washers mounted on rubber bands stretched across a framework. The rigidly…

  8. The Calculus of Elasticity

    ERIC Educational Resources Information Center

    Gordon, Warren B.

    2006-01-01

    This paper examines the elasticity of demand, and shows that geometrically, it may be interpreted as the ratio of two simple distances along the tangent line: the distance from the point on the curve to the x-intercept to the distance from the point on the curve to the y-intercept. It also shows that total revenue is maximized at the transition…

  9. Elastically tailored composite structures

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Elastically tailored composite structures using out-of-autoclave processes. Several unsymetric autoclave-cured and electron-beam-cured composite laminates are compared. Cantilevered beam (unbalanced/asymetric laminate) used to demonstrate bend-twist coupling effects. Photographed in building 1145, photographic studio.

  10. Renormalization of curvature elastic constants for elastic and fluid membranes

    NASA Astrophysics Data System (ADS)

    Ami, S.; Kleinert, H.

    1987-02-01

    We study the fluctuations of membranes with area and curvature elasticity and calculate the renormalization of the curvature elastic constants due to thermal fluctuations. For the mean curvature elastic constant the result is the same as obtained previously for “ideal membranes” which resist only to curvature deformations. The renormalization of the gaussian curvature, on the other hand, depends on the elastic contants. In an incompressible membrane, it is five times weaker than in an ideal membrane.