3,700 research outputs found
Influence of final state interaction on incoherent pion photoproduction on the deuteron in the region of the Delta-resonance
The influence of final state - and pi N-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, pi N-rescattering is
almost negligible. Inclusion of such effects leads to an improved and quite
satisfactory agreement with experiment.Comment: 18 pages revtex4 including 16 postscript figure
Spin observables for pion photoproduction on the deuteron in the (1232)-resonance region
Spin observables for the three charge states of the pion for the pion
photoproduction reaction on the deuteron, , with polarized
photon beam and/or oriented deuteron target are predicted. For the beam-target
double-spin asymmetries, it is found that only the longitudinal asymmetries
and do not vanish, whereas all the circular
and the other longitudinal asymmetries do vanish. The sensitivity of spin
observables to the model deuteron wave function is investigated. It has been
found that only and are sensitive to the model deuteron wave
function, in particular in the case of -production above the
-region, and that other asymmetries are not.Comment: 16 pages, 8 figures, accepted for publication in J. Phys. G: Nucl.
Part. Phy
Polarization observables of the gamma d --> PiNN reaction in the Delta(1232)-resonance region
Polarization observables of the three charge states of the pion for the
reaction with polarized photon beam and/or oriented
deuteron target are evaluated over the whole (1232)-resonance region
adopting a nonrelativistic model based on time-ordered perturbation theory.
Results for the -meson spectra, linear photon asymmetry, vector and tensor
target asymmetries are presented. Particular attention is given, for the first
time, to double polarization asymmetries for which we present results for
and . We found that all other double
polarization asymmetries of photon and deuteron target are vanished.Comment: 17 Pages, 8 Figures, accepted for publication in Int. J. Mod. Phys.
The Teaching of Switched Mode Power Supplies - Design, Simulation and Practical Implementation for Undergraduate and Postgraduate Students
© 2018 IEEE. The teaching of switched mode power supplies can be very challenging. For example, do we just teach the operation of the power supplies? Is teaching a topology enough to produce a graduate capable of designing power supplies for the highest specifications? Should we consider other details like EMI, thermal effects and packaging in the design? What will happen if we ignore them? Should these details be considered at the simulation stage, or only when it comes to manufacturing phase? This paper covers all the steps required for the design procedure of switched mode power supplies. The paper can be used in developing practical/simulation courses in power electronics for teaching the design of switched mode power supplies
Factors influencing public attitudes toward paid online newspaper subscriptions- a field study
Despite the implementation of new business models in several Western media organizations, most Arab newspapers have not yet explored these models, and little is known about public attitudes towards their willingness to pay for online news. The study sought to identify factors that encourage the public to pay. It was applied to a sample of 530 newspaper consumers in the UAE, Saudi Arabia, and Oman. The study concluded that there are unfavorable trends in the public regarding their interest in following up on the news and did not show willingness for paying for online news. Most of them prefer to pay for entertainment materials. The study found that demographic variables such as age and income were important indicators of the public’s willingness to pay. Most respondents were not yet exposed to the paywall and anticipated difficulty in implementing the culture of paying for online news in Arab societies. They also expected that many print newspapers will disappear in the near future, and the idea of paying for online news was not seen favorably
A remark on certain p
The object of the present paper is to prove an interesting result for
certain analytic and p-valent functions in the unit disc U={z:|z|<1}
Mean parity of single quantum excitation of some optical fields in thermal environments
The mean parity (the Wigner function at the origin) of excited binomial
states, excited coherent states and excited thermal states in thermal channel
is investigated in details. It is found that the single-photon excited binomial
state and the single-photon excited coherent state exhibit certain similarity
in the aspect of their mean parity in the thermal channel. We show the negative
mean parity can be regarded as an indicator of nonclassicality of single-photon
excitation of optical fields with a little coherence, especially for the
single-photon excited thermal states.Comment: 4 pages, 4 figures, RevTex4; PACS numbers: 42.50.Dv, 03.65.Yz,
05.40.Ca; Three typo errors have been correcte
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