Calculation of Kstopped− absorption yields on light nuclei

This paper describes an atomic cascade model which is used to predict the absorption yields for a kaon at low orbits in [Formula: see text]Li,9Be,[Formula: see text]C and [Formula: see text]O nuclei. The calculations show that most of the absorptions occur in [Formula: see text] and [Formula: see text] states so that their contribution adds up to 100% for [Formula: see text]O. However, for all of the targets, absorption in the other states is nearly zero. Also by increasing atomic number of target [Formula: see text], the yield of [Formula: see text] states decreases while it increases for the [Formula: see text] states. The results also display a low sensitivity on the widths of 4[Formula: see text] state (0.1%), in which it is comparable with the natural width of the radiation transition [Formula: see text].

Неклассические источники света на основе селективно позиционированных микролинзовых структур и (111) In(Ga)As квантовых точек

Hybrid microcavity for single quantum dot based emitters has been developed and realized. The microcavity consists of semiconductor distributed Bragg reflector and microlens, which is selectively positioned over a single (111) In(Ga)As quantum dot. We have demonstrated pure single photon emission with g(2)(0) = 0.07. The fine structure of exciton states of (111) In(Ga)As quantum dots is studied. It is shown that the splitting of exciton states is comparable with the natural width of exciton lines, which is of great interest for the design of emitters of pairs of entangled photons on the basis of these quantum dots.

Спектроскопия одиночных AlInAs- и (111)InGaAs-квантовых точек

A system of AlInAs- and InGaAs(111)-based quantum dots is studied. The use of wide-gap Al_ x In_1 –_ x As alloys as a basis for quantum dots provides a means for substantially extending the spectral region of emission to shorter wavelengths, including the region close to 770 nm which is of interest for the engineering of aerospace systems of quantum cryptography. The fine structure of exciton states in AlInAs and InGaAs(111) quantum dots is studied. It is shown that, for a set of quantum dots, the splitting of exciton states is comparable to the natural width of exciton lines, which is of interest for the engineering of emitters of photon pairs on the basis of these quantum dots.

HIDDEN CHARM SPECTROSCOPY FROM TEVATRON

The observation of a narrow structure near the J/ψ ϕ threshold in exclusive B+ → J/ψ ϕ K+ decays produced in [Formula: see text] collisions at [Formula: see text] is reported. A signal of 19 ± 6(stat) ± 3(syst) events, with statistical significance of 5.0 standard deviations, is seen in a data sample corresponding to an integrated luminosity of 6.0 fb-1, collected by the CDF II detector. The mass and natural width of the structure are determined to be [Formula: see text] and [Formula: see text], consistent with the previous measurements reported as evidence of the Y(4140).