Response to the Letter to the Editor

Journal of Nanoparticle Research -     

Proposal to improve the behaviour of self-energy contributions to the S-matrix

A simple modification of the definition of the S-matrix is proposed. It is expected that the divergences related to nonzero self-energies are considerably milder with the modified definition than with the usual one. This conjecture is verified in a few examples using perturbation theory. The proposed formula is written in terms of the total Hamiltonian operator and a free Hamiltonian operator and is therefore applicable in any case when these Hamiltonian operators are known.     

潮汐对地球自转阻滞作用的估计

讨论了潮汐阻滞地球自转的机制,利用一个简化的模型计算了由潮汐引起的地球自转角加速度的数量级,得到了比较满意的结果,并讨论了几个简化假设的合理性,还利用该模型计算了当地球自转速度不再变化时的几个数据.     

在新课改中如何把复习课的自主权还给学生

以往的复习课，一般都是教师课前准备大量的练习题让学生去做，以求考试中能考到同类型的题目，导致学生成了“知识的容器”．一到考试，学生就赶紧巡视一下题目是否做过，如果稍微发生变化就会无所适从．这样的复习课是为复习而复习，为训练而训练，学生越来越感到枯燥无味，对学习失去兴趣，更谈不上感受学习的快乐，学习效果自然可想而知．新课程理念不仅要求学生学会知识，更突出要求培养学生会学的能力．在实施新课程的今天，如何上好复习课，如何做到把复习课的自主权还给学生，真正地提高复习课的效率，已成为广大教师面临的研讨话题之一．笔者曾尝试从以下5个方面去改进复习课，愿抛砖引玉，与同行们一起探讨．     

Geminga contribution to the cosmic-ray positron excess according to the gamma-ray observations

We attempt to interpret the cosmic-ray positron excess by injection from the nearby pulsar Geminga, assuming a two-zone diffusion scenario and an injection spectrum with a low energy cutoff. Since the high energy positrons and electrons from Geminga can induce γ rays via inverse Compton scattering, we take into account the extended γ-ray observations around Geminga from HAWC for ∼10 TeV and from Fermi-LAT for ${ \mathcal O }(10)$ GeV. According to the extended γ-ray observation claimed by an analysis of Fermi-LAT data, we find that Geminga could explain the positron excess for a 30% energy conversion efficiency into positrons and electrons. However, based on the constraint on the extended γ rays given by another Fermi-LAT analysis, positrons from Geminga would be insufficient to account for the positron excess. Further robust analysis of Fermi-LAT data for the extended γ rays would be crucial to determine whether Geminga can explain the positron excess or not.     

Polarization Analysis to Separate the Resonance Contribution to the Allowed X-Ray Reflections

JETP Letters - It has been shown that channels of resonant X-ray scattering with a change in polarization can be present in allowed Bragg reflections. The measurement of the energy and azimuthal...     

Answer to the comments

The dynamical method previously proposed for detecting water clusters under atmospheric conditions after the adiabatic expansion of the gas mixture under investigation has been additionally justified. New experimental results of the detection of absorption induced by water clusters near 10600 cm⁻¹ with a resolution of about 1.5 cm⁻¹ are reported.