1,841 research outputs found
Multiple scattering effects on heavy meson production in p+A collisions at backward rapidity
We study the incoherent multiple scattering effects on heavy meson production
in the backward rapidity region of p+A collisions within the generalized
high-twist factorization formalism. We calculate explicitly the double
scattering contributions to the heavy meson differential cross sections by
taking into account both initial-state and final-state interactions, and find
that these corrections are positive. We further evaluate the nuclear
modification factor for muons that come form the semi-leptonic decays of heavy
flavor mesons. Phenomenological applications in d+Au collisions at a
center-of-mass energy GeV at RHIC and in p+Pb collisions at
TeV at the LHC are presented. We find that incoherent multiple
scattering can describe rather well the observed nuclear enhancement in the
intermediate region for such reactions.Comment: 10 pages, 6 figures, published version in PL
Metali u medu iz provincije Henan, Kina: sustavna analiza metodom ICP-AES
In this study, the method for determining ten elements (including K, Na, Ca, Mg, Fe, Mn, Cu, Zn, Pb, and Cd) was designed. With this method, we evaluated 15 honey samples, including three kinds of honey collected from 11 different geographic sites in Henan province of China, with inductively coupled plasma atomic emission spectrometry (ICP-AES). The obtained detecting data were analysed with principal component analysis, correlation analysis, and cluster analysis techniques. The results showed that the recovery is in the range of 93.0−107.0 %, and the relative standard deviations (RSDs) were all below 5.89 %, which indicates that the current analytical method is dependable for the detection of metallic elements in honey.
This work is licensed under a Creative Commons Attribution 4.0 International License.U ovom istraživanju osmišljena je metoda određivanja deset elemenata (K, Na, Ca, Mg, Fe, Mn, Cu, Zn, Pb i Cd). Tom metodom evaluirano je 15 uzoraka meda, uključujući tri vrste meda prikupljenih s 11 lokaliteta u provinciji Henan, Kina, atomskom emisijskom spektrometrijom s induktivno spregnutom plazmom (ICP-AES). Dobiveni podatci proučeni su analizom glavnih komponenti, korelacijskom analizom i tehnikama klasterskih analiza. Rezultati su pokazali da se oporaba kreće u rasponu od 93,0 do 107,0 %, a relativne standardne devijacije (RSD) bile su ispod 5,89 %, što ukazuje da je trenutačna analitička metoda pouzdana za otkrivanje metala u medu.
Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna
Quantum Anomalous Hall Effect in HgMnTe Quantum Wells
The quantum Hall effect is usually observed when the two-dimensional electron
gas is subjected to an external magnetic field, so that their quantum states
form Landau levels. In this work we predict that a new phenomenon, the quantum
anomalous Hall effect, can be realized in HgMnTe quantum wells,
without the external magnetic field and the associated Landau levels. This
effect arises purely from the spin polarization of the atoms, and the
quantized Hall conductance is predicted for a range of quantum well thickness
and the concentration of the atoms. This effect enables dissipationless
charge current in spintronics devices.Comment: 5 pages, 3 figures. For high resolution figures see final published
version when availabl
A Time-independent Way to Probe D^0-\bar D^0 Mixing at Tau-charm Factories
mixing leads to the mass and width differences in the mass
eigenstates of and mesons (measured by parameters
and respectively), but their magnitudes cannot be reliably predicted
by the standard model. We show that it is possible to separately determine
and through {\it time-integrated} measurements of the
dilepton events of coherent decays on the resonance
at a -charm factory.Comment: 7 pages. Minor changes. (Phys. Lett. B in press
Relating the neutrino mixing angles to a lepton mass hierarchy
We propose two phenomenological scenarios of lepton mass matrices and show
that either of them can exactly give rise to \tan^2\theta_{13} = m_e/(m_e +
2m_\mu), \tan^2\theta_{23} = m_\mu/(m_e + m_\mu) and \tan^2\theta_{12} = (m_e
m_2 + 2m_\mu m_1)/(m_e m_1 + 2m_\mu m_2) in the standard parametrization of
lepton flavor mixing. The third relation, together with current experimental
data, predicts a normal but weak hierarchy for the neutrino mass spectrum. We
also obtain \theta_{13} \approx 2.8^\circ for the smallest neutrino mixing
angle and J \approx 1.1% for the Jarlskog invariant of leptonic CP violation,
which will soon be tested in the long-baseline reactor and accelerator neutrino
oscillation experiments. A seesaw realization of both scenarios is briefly
discussed.Comment: RevTeX 11 pages. Accepted for publicatio
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