共查询到20条相似文献,搜索用时 468 毫秒
1.
A. B. Balakin V. V. Bochkarev N. O. Tarasova 《The European Physical Journal C - Particles and Fields》2012,72(2):1895
We establish an extended version of the Einstein–Maxwell-axion model by introducing into the Lagrangian cross-terms, which
contain the gradient four-vector of the pseudoscalar (axion) field in convolution with the Maxwell tensor. The gradient model
of the axion–photon coupling is applied to cosmology: we analyze the Bianchi-I type Universe with an initial magnetic field,
electric field induced by the axion–photon interaction, cosmological constant and dark matter, which is described in terms
of the pseudoscalar (axion) field. Analytical, qualitative and numerical results are presented in detail for two distinguished
epochs: first, for the early Universe with magnetic field domination; second, for the stage of late-time accelerated expansion. 相似文献
2.
Andrei Khrennikov 《Journal of Russian Laser Research》2012,33(3):247-254
We consider the old foundational problem of quantum/classical optics ?C indivisibility of photon. Quantum theory predicts that in experiments on coincidence detection double clicks are impossible (up to noise); on the other hand, the known semiclassical and classical models predict a relatively high rate of coincidence. We present a model of the classical (random) wave type which predicts that in the same way as in quantum optics coincidence of clicks is a rare event. However, this model has a new prediction compared to quantum optics, namely, that the rate of double clicks depends substantially on the discrimination threshold of a detector. We propose to perform new detailed tests to check the discrimination threshold dependence predicted by our model. In experiments on coincidence detection performed to date, for example, the Grangier experiment does not contain statistical data on the threshold dependence. 相似文献
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In this Letter, we present a possible methodology to directly “read” the force on an atom via the photons emitted from the atom. In this methodology, the mean radiative force on an atom exerted by external fields can be expressed as a function of the average number of emitted photons h N i and its derivatives via the generating function approach developed by us recently. 相似文献
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We present first results of a systematic study of the structure of the low-energy limit of the one-loop photon–graviton amplitudes induced by massive scalars and spinors. Our main objective is the search of KLT-type relations where effectively two photons merge into a graviton. We find such a relation at the graviton–photon–photon level. We also derive the diffeomorphism Ward identity for the 1PI one-graviton–N-photon amplitudes. 相似文献
6.
The photon magnetic moment for radiation propagating in magnetized vacuum is defined as a pseudotensor quantity, proportional to the external electromagnetic field tensor. After expanding the eigenvalues of the polarization operator in powers of \(k^2\) , we obtain approximate dispersion equations (cubic in \(k^2\) ), and analytic solutions for the photon magnetic moment, valid for low momentum and/or large magnetic field. The paramagnetic photon experiences a redshift, with opposite sign to the gravitational one, which differs for parallel and perpendicular polarizations. It is due to the drain of photon transverse momentum and energy by the external field. By defining an effective transverse momentum, the constancy of the speed of light orthogonal to the field is guaranteed. We conclude that the propagation of the photon non-parallel to the magnetic direction behaves as if there is a quantum compression of the vacuum or a warp of space-time in an amount depending on its angle with regard to the field. 相似文献
7.
Theoretical modelling of the effect of photon lifetime on the output dynamics of Er-doped distributed feedback fibre lasers 下载免费PDF全文
By employing a simple model of describing three-level lasers, we have theoretically investigated the effect of photon lifetime on the output dynamics of Er-doped distributed feedback fibre lasers. And based on the theoretical analysis we have proposed a promising method to suppress self-pulsing behaviour in the fibre lasers. 相似文献
8.
We investigate the feasibility of studying the photon structure function at a e-collider. We show that the deep inelastic probe of the real photon by a highly virtual photon in such a collider will extend significantly thex andQ
2 range presently accessible ate
+
e
– colliders. In addition, we study the production of large transverse momentum dijet final states to determine the sensitivity of these cross sections to different parametrisations of the quark and gluon distributions in the photon. 相似文献
9.
Yoshio Kitadono Ryo Sahara Tsuneo Uematsu Takahiro Ueda 《The European Physical Journal C - Particles and Fields》2010,70(4):999-1007
We discuss the resummation of the large logarithmic terms appearing in the heavy-quark effects on parton distribution functions
inside the virtual photon. We incorporate heavy-quark mass effects by changing the initial condition of the leading-order
DGLAP evolution equation. In a certain kinematical limit, we recover the logarithmic terms of the next-to-leading order heavy-quark
effects obtained in the previous work. This method enables us to resum the large logarithmic terms due to heavy-quark mass
effects on the parton distributions in the virtual photon. We numerically calculate parton distributions using the formulae
derived in this work, and we discuss the property of the resummed heavy-quark effects. 相似文献
10.
Energy average formula of photon gas rederived by using the generalised Hermann-Feynman theorem 下载免费PDF全文
By virtue of the generalised Hermann-Feynmam theorem we re-derive the energy average formula of photon gas. This is another useful application of the theorem. 相似文献
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Qauntumtheoryoftwo-photonabsorptioninadrivenF-PcavitywiththefeedbackofphotonfluxLIUJiaren;WAdeYuzhu(JointLaboratoryforQuantum... 相似文献
13.
We developed a sol–gel method using the dressed photon–phonon (DPP) process. DPPs are selectively exited in nanoscale structures at photon energies that are lower than the bandgap energy, which allows one to increase the growth rate of smaller ZnO quantum dots (QDs). Thus, we obtained a smaller size variance of ZnO QDs. The growth rate was proportional to the power of the light used for DPP excitation. The results were confirmed using a rate equation that accounted for the concentration of the sol–gel solution. 相似文献
14.
《Journal of Quantitative Spectroscopy & Radiative Transfer》1997,58(1):141-143
A recent examination of photon scattering in the solar interior by Tsytovich et al. [JQSRT 55, 787 (1996)] is shown to interpret incorrectly past calculations of the Raman resonance and Doppler shift contributions. 相似文献
15.
Sameen Ahmed Khan 《Optik》2011,122(15):1324-1325
In their most recent article, Grado-Caffaro et al. have addressed the question of the ‘photon velocity’. They have expressed the photon velocity in terms of the wavefunctions of the Klein-Gordon equation (Grado-Caffaro and Grado-Caffaro [4]). In this note, we closely follow their work and explicitly obtain the photon velocity using the free solutions of the Klein-Gordon equation. It is shown that the plane wave solutions give rise to six possible values of the photon velocity. Two of these solutions are the most expected (v=±c). The remaining four solutions, the real pair ±0.786c and the imaginary pair ±1.272ic are difficult to comprehend. 相似文献
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《中国光学快报(英文版)》2008,(9)
Single photon counting imaging technology has been widely used in space environment detection,astronomy observation,nuclear physics,and ultraweak bioluminescenee.However,the distortion of the single photon counting image will badly affect the measurement results.Therefore,the correction of distortion for single photon counting image is very significant.Ultraviolet single photon imaging system with wedge and strip anode is introduced and the infhlence factor leading to image distortion is analyzed.To correct original distorted image,three different image correction methods,namely,the physical correction,the global correction,and the local correction,are applied.In addition,two parameters,i.e.,the position index and the linearity index,are defined to evaluate the performance of the three methods.The results suggest that the correction methods can improve the quality of the initial image without losing gray information of each counting light spot.And the local correction can provide the best visual inspections and performance evaluation among the three methods. 相似文献
18.
The absolute energy calibration with photons from π0's for the BESⅢ EMC is discussed. Using 3 million hadronic events, the preliminary results are presented. Precision of about 1% in the photon energy measurement is obtained from crossing check using photons in ψ(2S)→γχc1,2(1P). 相似文献
19.
Mirzabek Alloqulov Farruh Atamurotov Ahmadjon Abdujabbarov Bobomurat Ahmedov 《中国物理C(英文版)》2023,(7):190-203
We study the particle motion around a black hole(BH) in Ho?ava-Lifshitz(HL) gravity with the Kehagias-Sfetsos(KS) parameter. First, the innermost stable circular orbit(ISCO) is obtained for massive particles around the BH in HL gravity. We find that the radii of the ISCOs decrease as the KS parameter decreases, meaning that the parameter ? causes the orbits of particles to move inward with respect to that of the Schwarzschild BH case.Then, the optical properties of a KS BH are studied in detail,... 相似文献
20.
BIAN Jian-Ming HE Kang-Lin LI Wei-Guo HU Tao FU Cheng-Dong HUANG Bin LIU Ying NING Fei-Peng SONG Wen-Bo SUN Sheng-Sen XU Min YAN Jie YAN Liang 《中国物理C(英文版)》2010,34(1):72-77
The absolute energy calibration with photons from π0's for the BESⅢ EMC is discussed. Using 3 million hadronic events, the preliminary results are
presented. Precision of about 1% in the photon energy measurement is
obtained from crossing check using photons in ψ(2S)→γχc1,2(1P). 相似文献
presented. Precision of about 1% in the photon energy measurement is
obtained from crossing check using photons in ψ(2S)→γχc1,2(1P). 相似文献