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41.
W. Bell K. Braune G. Claesson D. Drijard M. A. Faessler H. G. Fischer H. Frehse R. W. Frey S. Garpman W. Geist C. Gruhn P. Hanke M. Heiden W. Herr P. G. Innocenti T. J. Ketel E. E. Kluge I. Lund G. Mornacchi T. Nakada I. Otterlund M. Panter B. Povh A. Putzer E. Stenlund T. J. M. Symons R. Szwed O. Ullaland 《Zeitschrift fur Physik C Particles and Fields》1986,30(4):513-520
Properties of secondaries associated with a high-p T charged trigger particle (3<p T <5 GeV/c) were studied for αp and αα interactions at c.m. energies \(\sqrt s = 88\) GeV and 125 GeV, respectively. Thep T distributions of secondaries in the away-jet and trigger-jet regions were compared with those for high-p T pp interactions. No statistically significant differences were seen, except at lowp T . Momentum and angular distributions of spectator and leading protons were studied as a function of charge and rapidity of the trigger hadron. The observed correlations between trigger charge and number of spectator protons provide evidence of valence quark contributions to the trigger jet. 相似文献
42.
43.
Liebschner A Hanke W Miersch L Dehnhardt G Sauerland M 《The Journal of the Acoustical Society of America》2005,117(1):436-441
Auditory systems of cetaceans are considered highly specialized for underwater sound processing, whereas the extent of their hearing capacity in air is still a point of issue. In this study, the sensitivity to airborne sound in a male tucuxi (Sotalia fluviatilis guianensis) was tested by means of a go/no go response paradigm. Auditory thresholds were obtained from 2 to 31.5 kHz. Compared to the hearing thresholds of other dolphins as well as of amphibian mammals, the sensitivity to airborne sound of the test subject is low from 2 to 8 kHz, with the highest threshold at 4 kHz. Thresholds at 16 and 31.5 kHz reveal a sharp increase in hearing sensitivity. Thus, although not obtained in this study, the upper aerial hearing limit is in the ultrasonic range. A comparison of the present data with the underwater audiogram of the same test subject referred to sound intensity indicates that the sensitivity of Sotalia to underwater sound is generally better than to airborne sound. 相似文献
44.
Deokki Min Nils Hoivik Geir Uri Jensen Frode Tyholdt Camilla Haavik Ulrik Hanke 《Applied Physics A: Materials Science & Processing》2011,105(4):867-874
The dielectric properties of zirconium dioxide (ZrO2) ceramic thin films were characterized up to 50 GHz using coplanar waveguides (CPWs) and metal–insulator–metal (MIM) capacitors
with top circular electrodes. The ZrO2 films were deposited using a chemical solution onto high-resistivity Si wafers and metal layers. The real part of the dielectric
constant of approximately 22 and 26 was extracted at 50 GHz for CPW and MIM structures, respectively, and the loss tangent
was approximately 0.09 at 50 GHz. C–V and I–V measurements were carried out to determine low-frequency and DC dielectric properties. The measurement results indicate that
ZrO2 is a promising material to be used as a dielectric layer for radio-frequency (RF) microelectromechanical systems (MEMS) capacitive
switches. 相似文献
45.
M. Schmidbauer P. Schäfer S. Besedin D. Grigoriev R. Köhler M. Hanke 《Journal of synchrotron radiation》2008,15(6):549-557
A new scattering technique in grazing‐incidence X‐ray diffraction geometry is described which enables three‐dimensional mapping of reciprocal space by a single rocking scan of the sample. This is achieved by using a two‐dimensional detector. The new set‐up is discussed in terms of angular resolution and dynamic range of scattered intensity. As an example the diffuse scattering from a strained multilayer of self‐assembled (In,Ga)As quantum dots grown on GaAs substrate is presented. 相似文献
46.
Höpfner P Schäfer J Fleszar A Dil JH Slomski B Meier F Loho C Blumenstein C Patthey L Hanke W Claessen R 《Physical review letters》2012,108(18):186801
The spin texture of the metallic two-dimensional electron system (sqrt[3]×sqrt[3])-Au/Ge(111) is revealed by fully three-dimensional spin-resolved photoemission, as well as by density functional calculations. The large hexagonal Fermi surface, generated by the Au atoms, shows a significant splitting due to spin-orbit interactions. The planar components of the spin exhibit a helical character, accompanied by a strong out-of-plane spin component with alternating signs along the six Fermi surface sections. Moreover, in-plane spin rotations toward a radial direction are observed close to the hexagon corners. Such a threefold-symmetric spin pattern is not described by the conventional Rashba model. Instead, it reveals an interplay with Dresselhaus-like spin-orbit effects as a result of the crystalline anisotropies. 相似文献
47.
W. Hanke M.L. Kiesel M. Aichhorn S. Brehm E. Arrigoni 《The European physical journal. Special topics》2010,188(1):15-32
One central challenge in high-T
c superconductivity (SC) is to derive a detailed understanding for the specific role of the Cu-d
x2-y2 and O-p
x,y
orbital degrees of freedom. In most theoretical studies an effective one-band Hubbard (1BH) or t-J model has been used. Here,
the physics is that of doping into a Mott-insulator, whereas the actual high-T
c cuprates are doped charge-transfer insulators. To shed light on the related question, where the material-dependent physics
enters, we compare the competing magnetic and superconducting phases in the ground state, the single- and two-particle excitations
and, in particular, the pairing interaction and its dynamics in the three-band Hubbard (3BH) and 1BH-models. Using a cluster
embedding scheme, i.e. the variational cluster approach (VCA), we find which frequencies are relevant for pairing in the two
models as a function of interaction strength and doping: in the 3BH-models the interaction in the low- to optimal-doping regime
is dominated by retarded pairing due to low-energy spin fluctuations with surprisingly little influence of inter-band (p-d
charge) fluctuations. On the other hand, in the 1BH-model, in addition a part comes from “high-energy” excited states (Hubbard
band), which may be identified with a non-retarded contribution. We find these differences between a charge-transfer and a
Mott insulator to be renormalized away for the ground-state phase diagram of the 3BH- and 1BH-models, which are in close overall
agreement, i.e. are “universal”. On the other hand, we expect the differences - and thus, the material dependence to show
up in the “non-universal” finite-T phase diagram (T
c-values). 相似文献
48.
Christopher Allday Bernhard Hanke Volker Puppe 《Proceedings of the American Mathematical Society》2003,131(10):3275-3283
Let , or more generally be a finite -group, where is an odd prime. If acts on a space whose cohomology ring fulfills Poincaré duality (with appropriate coefficients ), we prove a mod congruence between the total Betti number of and a number which depends only on the -module structure of . This improves the well known mod congruences that hold for actions on general spaces.
49.
An important component of any initial-value solver for higher-index differential–algebraic equations consists in the computation of consistent initial values. In a recent paper [5], an algorithm is proposed which is applicable to a very general class of index-2 systems. Unfortunately, the computational expense is rather high. We present a modification of this approach, which gives rise to a MATLAB implementation capable of handling systems of moderate dimension (several thousands of unknowns). The algorithm is illustrated by examples. 相似文献
50.
A. Breakstone C. D. Buchanan R. Campanini H. B. Crawley M. Cuffiani G. M. Dallavalle M. M. Deninno K. Doroba D. Drijard F. Fabbri A. Firestone H. G. Fischer H. Flöge H. Frehse W. M. Geist L. Gesswein G. Giacomelli R. Gokieli M. Gorbics M. Gorski P. Hanke M. Heiden D. Isenhower E. E. Kluge J. W. Lamsa T. Lohse R. Mankel W. T. Meyer T. Nakada M. Panter A. Putzer K. Rauschnabel B. Rensch F. Rimondi M. Schmelling G. P. Siroli J. Skeens R. Sosnowski M. Szczekowski O. Ullaland D. Wegener R. Yeung 《Zeitschrift fur Physik C Particles and Fields》1991,52(4):551-557