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1.
J/ψ and decays to mesons are a good place to look for glueballs, hybrids and for extracting strange and non-strange components in
mesons. Abundant J/ψ and events have been collected at the Beijing Electron Positron Collider (BEPC). More data will be collected at upgraded BEPC
and CLEO-C. Here we provide explicit PWA formulae for many interesting channels in the covariant tensor formalism.
Received: 29 November 2002 / Accepted: 20 December 2002 / Published online: 25 March 2003
RID="a"
ID="a"e-mail: zoubs@mail.ihep.ac.cn
Communicated by V.V. Anisovich 相似文献
2.
3.
T. Otsuka Y. Utsuno R. Fujimoto B.A. Brown M. Honma T. Mizusaki 《The European Physical Journal A - Hadrons and Nuclei》2002,15(1-2):151-155
Two recent developments of the nuclear shell model are presented. One is a breakthrough in computational feasibility owing
to the Monte Carlo Shell Model (MCSM). By the MCSM, the structure of low-lying states can be studied with realistic interactions
for a wide, nearly unlimited basically, variety of nuclei. The magic numbers are the key concept of the shell model, and are
shown to be different in exotic nuclei from those of stable nuclei. Its novel origin and robustness will be discussed.
Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
RID="a"
ID="a"e-mail: otsuka@phys.s.u-tokyo.ac.jp 相似文献
4.
Castelnovo M Bowles RK Reiss H Gelbart WM 《The European physical journal. E, Soft matter》2003,10(2):191-197
We consider the problem of inserting a stiff chain into a colloidal suspension of particles that interact with it through
excluded volume forces. The free energy of insertion is associated with the work of creating a cavity devoid of colloid and
sufficiently large to accommodate the chain. The corresponding work per unit length is the force that resists the entry of
the chain into the colloidal suspension. In the case of a hard sphere fluid, this work can be calculated straightforwardly
within the scaled particle theory; for solutions of flexible polymers, on the other hand, we employ simple scaling arguments.
The forces computed in these ways are shown, for nanometer chain and colloid diameters, to be of the order of tens of pN for solution volume fractions of a few tenths. These magnitudes are argued to be important for biophysical processes such
as the ejection of DNA from viral capsids into the cell cytoplasm.
Received 18 December 2002 Published online: 16 April 2003
RID="a"
ID="a"e-mail: castel@chem.ucla.edu
RID="b"
ID="b"Present address: Courant Institute of Mathematical Sciences, NYU, New York, New York 10012, USA 相似文献
5.
Gueroui Z Freyssingeas E Place C Berge B 《The European physical journal. E, Soft matter》2003,11(1):105-108
We observed fluctuations of elongated DNA molecules by fluorescence microscopy. The molecules are fixed at both ends and undulate.
Mode analysis of the thermally excited undulations of the labeled DNA molecules gives access to the spectral density of the
amplitude fluctuations. From these measurements we estimate the tension acting on the DNA molecules. We found the forces to
be within the entropic elasticity range of a typical DNA molecule (measured on the single-molecule level).
Received: 11 November 2002 / Accepted: 12 May 2002 / Published online: 4 June 2003
RID="a"
ID="a"Present address: Center for Studies in Physics and Biology, Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. e-mail: zoherg@rockefeller.edu 相似文献
6.
R. Fiore A. Flachi L.L. Jenkovszky A.I. Lengyel V.K. Magas 《The European Physical Journal A - Hadrons and Nuclei》2002,15(4):505-515
An explicit model realizing parton-hadron duality and fitting the data is suggested. Complex nonlinear Regge trajectories
are important ingredients of the model. The inclusion of Δ and N* trajectories should account for all resonances in the direct channel. The exotic trajectory is responsible for the smooth
background.
Received: 7 June 2002 / Accepted: 3 July 2002 / Published online: 10 December 2002
RID="a"
ID="a"e-mail: fiore@cs.infn.it
RID="b"
ID="b"e-mail: flachi@ifae.es
RID="c"
ID="c"e-mail: jenk@gluk.org
RID="d"
ID="d"e-mail: sasha@len.uzhgorod.ua
RID="e"
ID="e"e-mail: vladimir@cfif.ist.utl.pt
Communicated by V.V. Anisovich 相似文献
7.
O. Civitarese J. Suhonen H. Ejiri 《The European Physical Journal A - Hadrons and Nuclei》2003,16(3):353-358
We have performed a theoretical analysis of the ground-state-to-ground-state transitions in 100Mo and 116Cd, based on the quasiparticle random-phase approximation and on a straightforward perturbative scheme. The results show that
the single-state dominance found in the realistic calculations of the nuclear matrix elements, which is consistent with data,
can be viewed as a result of the interference between few two-quasiparticle configurations.
Received: 12 August 2002 / Accepted: 23 October 2002 / Published online: 18 February 2003
RID="a"
ID="a"e-mail: civitarese@fisica.unlp.edu.ar
Communicated by V.V. Anisovich 相似文献
8.
M.P. Rekalo E. Tomasi-Gustafsson 《The European Physical Journal A - Hadrons and Nuclei》2003,16(4):575-581
The associative charm particles production in nucleon-nucleon collisions N + N↦Λc(Σc) + ˉD + N, is described in a general way and the spin and isospin structure of the corresponding matrix elements are derived. Using
an analogy with strange-particle (ΛK) production, the D-meson exchange model is considered in detail. Estimations of the energy behavior of the threshold cross-sections show a large
dependence on the form of the phenomenological hadron form factors and indicate that, at threshold, the cross-section is three
orders of magnitude smaller than for strange-particle production.
Received: 18 October 2002 / Accepted: 5 December 2002 / Published online: 18 March 2003
RID="a"
ID="a"Permanent address: National Science Center KFTI, 310108 Kharkov, Ukraine.
RID="b"
ID="b"e-mail: etomasi@cea.fr
Communicated by V.V. Anisovich 相似文献
9.
R. Neugart 《The European Physical Journal A - Hadrons and Nuclei》2002,15(1-2):35-39
Lasers have played an important role for the development of new spectroscopy techniques yielding spins, electromagnetic moments
and charge radii of many unstable nuclei. More recently, similar techniques have been introduced to manipulate atoms and thus
to prepare beams or samples of radioactive atoms for various applications including nuclear spectroscopy and decay studies.
Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
RID="a"
ID="a"e-mail: rainer.neugart@uni-mainz.de 相似文献
10.
A new and general approach is proposed to analyze the dynamics of a colloidal particle interacting with a nearby wall. This
analysis can be used to determine the acting forces even when the system is non-stationary. As an illustration, we use total
internal reflection microscopy to investigate the forces acting on a polystyrene sulfate latex particle as it is receding
from a charged glass surface.
Received 10 October 2002 Published online: 16 April 2003
RID="a"
ID="a"Present address: Department of Polymer Physics, BASF Aktiengesellschaft, 67056 Ludwigshafen, Germany
RID="b"
ID="b"Present address: Arryx. Inc., Chicago, IL 60601, USA 相似文献
11.
We study the force-induced unfolding of random disordered RNA or single-stranded DNA polymers. The system undergoes a second-order
phase transition from a collapsed globular phase at low forces to an extensive necklace phase with a macroscopic end-to-end
distance at high forces. At low temperatures, the sequence inhomogeneities modify the critical behaviour. We provide numerical
evidence for the universality of the critical exponents which, by extrapolation of the scaling laws to zero force, contain
useful information on the ground-state (f = 0) properties. This provides a good method for quantitative studies of scaling exponents characterizing the collapsed globule.
In order to get rid of the blurring effect of thermal fluctuations, we restrict ourselves to the ground state at fixed external
force. We analyze the statistics of rearrangements, in particular below the critical force, and point out its implications
for force-extension experiments on single molecules.
Received 18 June 2002 and Received in final form 23 September 2002
RID="a"
ID="a"e-mail: muller@ipno.in2p3.fr 相似文献
12.
G. Bollen 《The European Physical Journal A - Hadrons and Nuclei》2002,15(1-2):237-243
Today ion traps are an important experimental tool. Applications range from high-precision measurements of masses and moments,
realization of atomic clocks, to the study of ion chemical reactions. Ion traps have gained particular importance in the field
of nuclear physics where they are used for the precise determination of nuclear binding energies, decay studies, and radioactive
ion beam manipulation.
Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
RID="a"
ID="a"e-mail: bollen@nscl.msu.edu 相似文献
13.
U.T. Yakhshiev U.-G. Meißner A. Wirzba 《The European Physical Journal A - Hadrons and Nuclei》2003,16(4):569-574
We investigate the possible modifications of the nucleons' electromagnetic form factors in the framework of a modified Skyrme
model allowing for nucleon deformation and using realistic nuclear mass distributions. We show that such effects are small
in light nuclei
Received: 19 November 2002 / Accepted: 3 December 2002 / Published online: 18 March 2003
RID="a"
ID="a"Address after January 1st, 2003: Helmholtz Institut für Strahlen- und Kernphysik (Theorie), Universit?t Bonn, Nu?allee
14-16, D-53115 Bonn, Germany; e-mail: meissner@itkp.uni-bonn.de
RID="b"
ID="b"Present address: Helmholtz Institut für Strahlen- und Kernphysik (Theorie), Universit?t Bonn, D-53115 Bonn, Germany.
Communicated by V. Vento 相似文献
14.
L.V. Grigorenko R.C. Johnson I.G. Mukha I.J. Thompson M.V. Zhukov 《The European Physical Journal A - Hadrons and Nuclei》2002,15(1-2):125-129
The theoretical approach to the two-proton radioactivity and three-body decays developed in (L.V. Grigorenko, R.C. Johnson,
I.G. Mukha, I.J. Thompson, M.V. Zhukov, Phys. Rev. Lett. 85, 22 (2000) and to be published in Phys. Rev. C) is applied to the range of light nuclear systems. We study nuclear structures,
widths, and momentum correlations for the decay fragments. Strong contradictions with experiment, as well as effects of special
interest, are found in 12O and 16Ne nuclei.
Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
RID="a"
ID="a"e-mail: l.grigorenko@surrey.ac.uk 相似文献
15.
E.M. Darwish H. Arenhövel M. Schwamb 《The European Physical Journal A - Hadrons and Nuclei》2003,16(1):111-125
The influence of final-state NN and πN rescattering in incoherent pion photoproduction on the deuteron has been investigated. For the elementary photoproduction
operator an effective Lagrangian model is used which describes well the elementary reaction. The interactions in the final
two-body subsystems are taken in separable form. While NN rescattering shows quite a significant effect, particularly strong for neutral pion production, πN rescattering is almost negligible. Inclusion of such effects leads to an improved and quite satisfactory agreement with experiment.
Received: 12 August 2002 / Accepted: 11 September 2002 / Published online: 17 January 2003
RID="a"
ID="a"Present address: Physics Department, Faculty of Science, South Valley University, Sohag, Egypt.
RID="b"
ID="b"e-mail: arenhoev@kph.uni-mainz.de
Communicated by V. Vento 相似文献
16.
B. Leblanc E. Lutton F. Axel 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(4):619-628
We present the first application of Genetic Algorithms to the analysis of data from an aperiodically ordered system, high
resolution X-Ray diffraction spectra from multilayer heterostructures arranged according to a deterministic or random scheme.
This method paves the way to the solution of the “inverse problem”, that is the retrieval of the generating disorder from
the investigation of the spectra of an unknown sample having non crystallographic, non quasi-crystallographic order.
Received 18 March 2002 / Received in final form 3 July 2002 Published online 31 October 2002
RID="a"
ID="a"e-mail: Evelyne.Lutton@inria.fr
RID="b"
ID="b"CNRS UMR 8502 相似文献
17.
W. Cassing L. Jarczyk B. Kamys P. Kulessa H. Ohm K. Pysz Z. Rudy O.W.B. Schult H. Ströher 《The European Physical Journal A - Hadrons and Nuclei》2003,16(4):549-561
The lifetime of the Λ-hyperon in heavy hypernuclei measured in proton-Au, -Bi and -U collisions by the COSY-13 Collaboration
at COSY-Jülich has been analyzed to yield τΛ = (145±11) ps. This value for τΛ is compatible with the lifetime extracted from antiproton annihilation on Bi and U targets, albeit much more accurate. Theoretical
models based on the meson exchange picture and assuming the validity of the phenomenological ΔI = 1/2 rule predict the lifetime of heavy hypernuclei to be significantly larger (2-3 standard deviations). Such large differences
indicate that at least one of the assumptions in these models is not fulfilled. A much better reproduction of the lifetimes
of heavy hypernuclei is achieved in the phase space model, if the ΔI = 1/2 rule is discarded in the nonmesonic Λ decay.
Received: 8 August 2002 / Accepted: 20 December 2002 / Published online: 25 March 2003
RID="a"
ID="a"e-mail: h.stroeher@fz-juelich.de
Communicated by Th. Walcher 相似文献
18.
V. Baru J. Haidenbauer C. Hanhart J.A. Niskanen 《The European Physical Journal A - Hadrons and Nuclei》2003,16(3):437-446
We present a new parameterization of the trinucleon wave function. As a novel feature a separable parameterization for the
complete wave function is given. In this way any calculation that considers two-body currents only is largely simplified.
To demonstrate this we calculate the π3He scattering length in chiral-perturbation theory. We find reasonable agreement with experimental values inferred from data
on level shifts in pionic 3He bound states. The relevance of the π-triton system for an alternative determination of the πN scattering lengths is discussed.
Received: 12 August 2002 / Accepted: 25 November 2002 / Published online: 25 February 2003
RID="a"
ID="a"e-mail: c.hanhart@fz.juelich.de
Communicated by V. Vento 相似文献
19.
D.V. Rao R. Cesareo A. Brunetti G.E. Gigante 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,23(1):43-49
Total Compton, individual shell and Compton energy-absorption scattering cross-sections are evaluated in the energy region
0.005 to 10 MeV for H, C, N, O, P and Ca. Compton energy absorption cross-sections deviate numerically with available values.
The cause of the numerical discrepancies are not fully understood but can be attributed to Doppler broadening of the Compton
scattered photons through a given angle.
Received 25 June 2002 / Received in final form 27 September 2002 Published online 3rd April 2003
RID="a"
ID="a"e-mail: dvrao@ssmain.uniss.it 相似文献
20.
Z. Iqbal Y. Zhang H. Grebel S. Vijayalakshmi A. Lahamer G. Benedek M. Bernasconi J. Cariboni I. Spagnolatti R. Sharma F.J. Owens M.E. Kozlov K.V. Rao M. Muhammed 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(4):509-515
Evidence is presented for the formation of a solid phase based on the smallest fullerene, C20, in thin diamond-like carbon films deposited by ultraviolet laser ablation from diamond onto nickel substrates at room temperature
in the presence of 10-4 torr of cyclohexane or benzene. Laser desorption mass spectrometry from the films shows the presence of C20, C21 and C22 species, while micro-Raman spectroscopy and electron diffraction from selected particles together with first principle density-functional
calculations, indicate a cubic solid with dodecahedral C20 cages as building blocks. Unlike solid C60 and fully protonated C20, which are bound by van der Waals forces, the proposed structure is stabilized by linking of the C20 dodecahedra with bridging carbon atoms at interstitial tetrahedral sites to form a face-centered-cubic lattice with 22 carbon
atoms per unit cell.
Received 10 October 2002 / Received in final form 24 December 2002 Published online 6 March 2003
RID="a"
ID="a"e-mail: zafar.iqbal@njit.edu 相似文献