Muon Spectra at Different Altitudes Derived from Bose-Type Model

The spectra of cosmic pions and kaons produced at the top of the atmosphere have been derived from the primary cosmic ray spectrum of GRIGOROV et al. by using the Bose-type model. With the help of pion and kaon atmospheric diffusion equations the muon spectra at different atmospheric depths viz., 690, 535 and 1033 g cm^?2 have been estimated. The results are in accord with the magnetic spectrograph data of KOCHARIAN et al. and ALLKOFER et al.     

Sea Level Muon Spectrum Derived from Bugaev Model Using the Primary Cosmic Ray Energy Spectrum of Grigorov et al

In a recent paper BHATTACHARYYA has derived the pion and kaon production spectra in the atmosphere using a form of the primary nucleon energy spectrum of the measurements of GRIGOROV et al. and the interaction model of BUGAEV et al. The sea level muon spectrum derived from these meson spectra agrees with the magnetic spectrograph data of ALLKOFER et al. and AYRE et al. In this report a critical analysis of the paper has been made and some obvious mistakes in the formulation have been pointed out. The formulation of BUGAEV et al. and the data of GRIGOROV at al. have been misinterpreted by BHATTACHARYYA . The corrected results have been properly interpreted in this report.     

Overview of the CKM physics opportunities beyond K^ + \to \pi ^ + \nu \bar \nu

A new experiment CKM is accepted by Fermilab for a very sensitive study of rare kaon decay $K^ + \to \pi ^ + \nu \bar \nu $ on an intense separated kaon beam. The high quality of the beam and CKM setup make it possible to perform an important set of other kaon-decay measurements in parallel with the main research program: (1) the search for new physics effects beyond the Standard Model (search for new P, S, T interactions and lepton flavor violation in kaon decays); (2) further search for direct CP violation in charged kaon decays; (3) study of low-energy hadron physics in pure conditions of decay processes (K ⁺ → π ⁺ l ⁺ l ^?; ππlν _l; π ⁰ γγ, etc.). The expected results of these studies are compared with other experimental programs.     

Neutral kaon production in p+p and p+Nb collisions

The kaon nucleus (KN) interaction in dense nuclear matter is predicted to be repulsive and increasing with density. However, determined values for this potential are not yet consistent with each other (Benabderrahmane et al., Phys Rev Lett 102:182501, 2009; Agakishiev et?al., Phys Rev C 82:044907, 2010; Büscher et?al., Eur Phys J A 22:301–317, 2004). We analyze $K^0_S$ mesons identified with the HADES detector in p+p and p+?⁹³Nb reactions at 3.5?GeV kinetic beam energy. To determine the KN potential at normal nuclear density we propose to compare the $K^0_S$ differential distributions in p+?⁹³Nb and p+p collisions. High statistics of low p _t -kaons (p _t ?<?100?MeV/c) ensure the sensitivity of our measurements to the nuclear matter effects. We present the data analysis method and first results.     

Calculations of some properties of the kaon

The wave functions of the bound state of the charged kaon are obtained from Bethe-Salpeter equation with the phenomenological vector-vector-type flat-bottom potential. The physical spacelike electromagnetic form factor of the charged kaon is calculated from the wave functions. The radius of the kaon is given from the electromagnetic form factor. The decay constant f _K of the kaon is estimated by the relationship between the decay constant and the normalization factor derived from the axial-vector Ward identity. All calculated results give a good fit to the experimental values.     

Charge transfer from chemical shifts at (110) surfaces of III–V compound semiconductors

Surface charge-transfer are calculated from surface core-level shifts determined by Eastman et al. and Taniguchi et al. by using soft X-ray photoemission spectroscopy. A simple electrostatic model which was first applied by Shevchik et al. to the analysis of bulk data is adapted for surfaces of compound semiconductors. The charge transferred from cations to anions is found to be the same in the bulk and at the (110) surfaces of GaP, GaAs, GaSb, and InSb.     

Rare K-meson decays, standard model, and new physics

A wide program of new investigations into rare kaon decays in experiments at IHEP, Fermilab, and Brookhaven National Laboratory accelerators is reviewed. Experiments aimed at studying low-energy hadronic processes in kaon decays, searches for new types of interactions, and investigation of CP-violation processes and of extremely rare flavor-changing neutral-current $K \to \pi \nu \bar \nu $ decays are the main components of this program. The relation of such processes to the Standard Model and new physics beyond it is discussed.     

Evidence of the Non-Strange Partner of Pentaquark from the Elementary K +Λ Photoproduction

The existence of the J ^p  = 1/2⁺ narrow resonance predicted by the chiral soliton model has been investigated by utilizing the new kaon photoproduction data. For this purpose, we have constructed two phenomenological models, which are able to describe kaon photoproduction from threshold up to W = 1,730 MeV. By varying the resonance mass, width, and KΛ branching ratio in this energy range we found that the most convincing mass of this resonance is 1,650 MeV. Using this result we estimate the masses of other antidecuplet family members.     

On the sensitivity of low energy weak interactions to large mass scales

It is discussed how known phenomenology from kaon, hyperon, charm and bottom decays makes it unlikely (though not impossible) that new states as suggested by composite models — namely spin zero partners ofW bosons or colour octet bosons — exist with a mass less than 1 TeV.     

Cosmological Constraint Revisited from K Band Galactic Counts

The information of Ω_Λ of a flat universe is extracted from K band galaxy number counts, without using evolution (NE) models. Cowie et al.'s observations, with model input luminosity functions taken from Efstathiou et al. (1988), Loveday et al. (1992) and Mobasher et al. (1993), give (Ω_Λ) in the range: 0.59～0.81 plus a typical random error of σ_ΩΛ = 0.2 -0.1, respectively. Keck's observations give Ω_Λ = 0.9. We conclude that either the normalization of nearby luminosity function is too high or the cosmological constant cannot be too large.     

Inclusive neutral kaon production in 70 GeV/c K+p interactions

The inclusive production of neutral kaons in 70 GeV/c K⁺p interactions is studied with the CERN BEBC bubble chamber. The (semi-)inclusive cross sections are interpreted in terms of the various strangeness channels leading to neutral kaon production. The invariant inclusive cross section for kaon production is studied as a function of p_t² and the Feynman variable x. The latter distributions are considered both “raw” and corrected for the presence of K⁰'s resulting from K¹ decay. They are compared with the predictions expected from the Regge-Mueller formalism, the recombination model and fragmentation models.     

Charged kaon condensation in high density quark matter

We show that at asymptotically high densities the “color-flavor-locked+neutral kaon condensate” phase of QCD develops a charged kaon condensate through the Coleman–Weinberg mechanism. At densities achievable in neutron stars a charged kaon condensate forms only for some (natural) values of the low energy constants describing the low-lying excitations of the ground state.     

Coulomb dissociation of 8B and solar neutrino problem

We measured the cross section for Coulomb dissociation of ⁸B using a radioactive ⁸B beam of 46.5 MeV/u energy with a ²⁰⁸Pb target. The corss section for the ⁷Be(p,γ)⁸B capture reaction was deduced at E_cm = 0.6 – 1.7 MeV. The extracted astrophysical S₁₇ factors were consistent with the values measured by Vaughn et al. and Filippone et al. Possible corrections due to ⁷Be excited state population, E1 and M2 contribution, nuclear contribution and post acceleration effects are considered.     

Infrared spectrum involving forbidden transitions & coriolis interaction and identification of optically pumped far infrared laser lines in asymmetrically mono-deuterated methanol (Methanol-D1)

In this paper new type of ΔK = 2 and 0 transitions have been identified in the Fourier Transform spectrum of Methanol-D₁ (CH₂DOH). These transitions are normally forbidden but a “Coriolis” type interaction with nearby states is believed to be contributing sufficient transition strength through intensity borrowing effect. This is the first time such forbidden transitions are reported to be identified in the excited states, in this molecule. The present conjecture is supported by observation of a many strong allowed transitions to upper terminating levels which are seen to be highly perturbed. This conclusion has been reached by comparing calculated energy levels using known molecular parameters (Pearson et al., 2012; Coudert et al., 2014; El Hilali et al., 2011; Quade et al., 1998; Richard Quade, 1998, 1999; Mukhopadhyay, 1997) and the actually observed FIR lines. The upper levels are seen to be upshifted from expected position. A closer look at the calculated energy values seems to indicate a possible interaction between the above states and other proximate torsional–rotational states could occur. The possible candidates for the interacting level manifolds are narrowed down through the presence of the forbidden transition. We also take the opportunity to propose alternate rotational quantum numbers for some of the assignments recently reported in the literature (El Hilali et al., 2011). Some ambiguities are pointed out on the data and the reported analysis. There remain too many such irregularities and we propose to gather a large body assigned transitions in a future catalog. Assignments and relevant comments on optically pumped FIR laser radiation are also made.     

Further measurement of the 7Be(p,γ)8B cross section at low energies with the coulomb dissociation of 8B

We have measured the dissociation of ⁸B in the Coulomb field of ²⁰⁸Pb at E_in=51.9 MeV/nucleon and extracted the cross section of the ⁷Be(p,γ)⁸B reaction at 0.4 ≤ E_rel≤ 3 MeV, which is of importance for the ⁸B solar-neutrino production rate. The extracted astrophysical S₁₇ factors are consistent with our earlier Coulomb dissociation measurement, and agree with the values deduced from the direct capture measurements by Filippone et al., Vaughn et al. and Hammache et al. The S factor at zero energy was extracted to be 18.9±1.8 eV-b with the help of theoretical energy-dependence. Received: 15 August 1998     

In-Medium Kaon Potential and Nuclear Equation of State Measured in Nucleus–Nucleus Collisions

The kaon production in heavy ion collisions at intermediate energies provides a sensitive probe to study the in-medium properties and nuclear equation of state of hadrons. Properties of kaons in dense hadronic matter are important for a better understanding of both, the possible restoration of chiral symmetry in dense hadronic matter and the properties of nuclear matter at high densities. We investigated the in-medium kaon potential and nuclear equation of state by transverse mass spectra of K ⁺ mesons in heavy ion collisions. We use quantum molecular dynamics (QMD) models based on covariant kaon dynamics to simulate ${_{28}^{58}Ni +_{28}^{58}Ni}$ collisions at 1.93 A GeV, to analyze the transverse mass spectra of K ⁺. Calculated results with a repulsive in-medium K ⁺N potential can reasonably describe the features of KaoS data. They also shown that the transverse mass spectrum of K ⁺ mesons is a sensitive observable to probe the kaon in-medium potential in dense nuclear matter.     

Calculation of effective material parameters by field averaging over lattices with non-negligible unit cell size

The Pendry et?al. field averaging method for calculation of effective material parameters is reviewed and its limits explored. The method is then extended so that it can accurately calculate the effective material parameters of lattices where the unit cell size is appreciable but still quasistatic (d??0.1?? ₀). The new algorithm is verified by calculating the effective material properties of periodically placed particles suspended in free space, as the unit cell size becomes appreciable. Results of our proposed formulation are then compared with the Pendry et?al. and conventional volumetric averaging algorithms.     

Isovector kaon form factor in the dispersion theory and S-wave π K-scattering lengths

A one-dimensional integral representation for isovector kaon form factor is constructed within the dispersion theory in terms of the pion form factor and the backwardπK-scattering amplitude. The normalization condition for isovector kaon form factor at zero momentum transfer gives a sum rule for theπK-scattering amplitude, with the use of which difference between thes-waveπK-scattering lengths in triplet and singlet isospin states is estimated to bea ₀ ^3/2 - a ₀ ^1/2 ≈μ ^{? 1} whereμ is the pion mass. In agreement with the vector-meson-dominance model, deviations of the isovector kaon form factor from half of the pion form factor are found to be small.     

Three-dimensional kaon and pion emission source extraction from √sNN = 200 GeV Au + Au collisions at RHIC-STAR

Three-dimensional source images for mid-rapidity, low transverse momentum kaon and pion pairs have been extracted from central Au + Au collisions data at √s _NN = 200 GeV by the STAR experiment at RHIC. The pion source function displays significant non-Gaussian features implying a finite pion emission duration. On the other hand, the kaon source function is essentially Gaussian, consistent with instantaneous emission from the fireball.     

An improved acoustic method for the determination of the Boltzmann constant at LNE-INM/CNAM

There is currently great interest in the international metrology community for new accurate determinations of the Boltzmann constant k, with a view to a new definition of the unit of thermodynamic temperature, the kelvin. Indeed, k is related to the quantum of energy kT, where T is the thermodynamic temperature.The value of the Boltzmann constant can be obtained from measurements of the velocity of the sound in a noble gas. In the method described here, the experiment is performed in a closed spherical cavity. To obtain an accurate value for k, all the parameters of the experiment (gas purity, static pressure, temperature of the device, exact shape of the cavity, etc.) have to be carefully controlled. As correction terms have to be applied to the acoustic signals, the validity of the theoretical models from which they are derived is crucial.The new determination carried out at the LNE-INM/CNAM is based on the same principles as in the acoustic experiment of Moldover et al. at NIST in 1988, which led to the most accurate determination of the Boltzmann constant up to now. However, several fundamental modifications and improvements have been made in this new experiment to measure and control the parameters that set the measured value of k. To cite this article: L. Pitre et al., C. R. Physique 10 (2009).