We report the final results of a study of the ψ(3770) meson using a data sample collected with the KEDR detector at the VEPP-4M electron–positron collider. The data analysis takes into account ...interference between the resonant and nonresonant DD¯ production, where the latter is related to the nonresonant part of the energy-dependent form factor FD. The vector dominance approach and several empirical parameterizations have been tried for the nonresonant FDNR(s).
Our results for the mass and total width of ψ(3770) areM=3779.2−1.7+1.8−0.7+0.5−0.3+0.3 MeV,Γ=24.9−4.0+4.6−0.6+0.5−0.9+0.2 MeV, where the first, second and third uncertainties are statistical, systematic and model, respectively. For the electron partial width two possible solutions have been found:(1)Γee=154−58+79−9+17−25+13 eV,(2)Γee=414−80+72−26+24−10+90 eV. Our statistics are insufficient to prefer one solution to another. The Solution (2) mitigates the problem of non-DD¯ decays but is disfavored by potential models.
It is shown that taking into account the resonance–continuum interference in the near-threshold region affects resonance parameters, thus the results presented cannot be directly compared with the corresponding PDG values obtained ignoring this effect.
The KEDR detector Anashin, V. V.; Aulchenko, V. M.; Baldin, E. M. ...
Physics of particles and nuclei,
07/2013, Letnik:
44, Številka:
4
Journal Article
Recenzirano
The KEDR detector is a universal magnetic detector designed for studying the
c
- and
b
-quarks and two-photon physics, and is employed at the VEPP-4M
e
+
e
−
collider. A specific feature of the ...experiment is the measurement of absolute beam energy using two methods: the resonant depolarization and the faster but less precise Compton backscattering of laser photons. This allowed a large series of measurements to be performed, in which the accuracy of determination of such fundamental parameters of particles as mass and total and leptonic widths was improved.
A high-precision determination of the main parameters of the ψ(2S) resonance has been performed with the KEDR detector at the VEPP-4M e+e− collider in three scans of the ψ(2S)–ψ(3770) energy range. ...Fitting the energy dependence of the multihadron cross section in the vicinity of the ψ(2S) we obtained the mass valueM=3686.114±0.007±0.011−0.012+0.002 MeV and the product of the electron partial width by the branching fraction into hadronsΓee×Bh=2.233±0.015±0.037±0.020 keV. The first and second uncertainties are statistical and systematic, respectively. The third uncertainty quoted is an estimate of the model dependence of the result due to assumptions on the interference effects in the cross section of the single-photon e+e− annihilation to hadrons explicitly considered in this work. Implicitly, the same assumptions were employed to obtain the charmonium leptonic width and the absolute branching fractions in many experiments.
Using the result presented and the world average values of the electron and hadron branching fractions, one obtains the electron partial width and the total width of the ψ(2S):Γee=2.282±0.015±0.038±0.021 keV,Γ=296±2±8±3 keV.
These results are consistent with and more than two times more precise than any of the previous experiments.
Applied Algebraic Dynamics Anashin, Vladimir; Khrennikov, Andrei
2009, 2009-06-02, Letnik:
49
eBook, Book
This monograph presents recent developments of the theory of algebraic dynamical systems and their applications to computer sciences, cryptography, cognitive sciences, psychology, image analysis, and ...numerical simulations. The most important mathematical results presented in this book are in the fields of ergodicity, p-adic numbers, and noncommutative groups. * For students and researchers working on the theory of dynamical systems, algebra, number theory, measure theory, computer sciences, cryptography, and image analysis."
Abstract Using the 1.32 $$\hbox {pb}^{-1}$$ pb - 1 statistics collected at the $$J/\psi $$ J / ψ peak with the KEDR detector at the VEPP-4M $$e^{+}e^{-\, }$$ e + e - collider, we measured the ...branching fractions of $$J/\psi $$ J / ψ meson decays to the final states 2( $$\pi ^{+}\pi ^{-})\pi ^{0}$$ π + π - ) π 0 , $$K^{+}K^{-}\pi ^{+}\pi ^{-}\pi ^{0}$$ K + K - π + π - π 0 , 2( $$\pi ^{+}\pi ^{-})$$ π + π - ) and $$K^{+}K^{-}\pi ^{+}\pi ^{-}$$ K + K - π + π - . The results obtained for the decays $$J/\psi \rightarrow $$ J / ψ → 2( $$\pi ^{+}\pi ^{-})\pi ^{0}$$ π + π - ) π 0 , $$J/\psi \rightarrow K^{+}K^{-}\pi ^{+}\pi ^{-}\pi ^{0}$$ J / ψ → K + K - π + π - π 0 contradict the measurements performed by other groups in the last century, but agree well with recent results of BABAR and BESIII collaborations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The product of the electronic width of the ψ(2S) meson and the branching fraction of its decay to the muon pair was measured in the e+e−→ψ(2S)→μ+μ− process using nine data sets corresponding to an ...integrated luminosity of about 6.5 pb−1 collected with the KEDR detector at the VEPP-4M electron–positron collider:Γee×Bμμ=19.3±0.3±0.5eV. Adding the previous KEDR results on hadronic and leptonic channels, the values of the ψ(2S) electronic width were obtained under two assumptions: either with the assumption of lepton universalityΓee=2.279±0.015±0.042keV or without it, summing up hadronic and three independent leptonic channelsΓee=2.282±0.015±0.042keV.
Every automaton (a letter-to-letter transducer) A whose both input and output alphabets are F
p
= {0, 1,...,
p
- 1} produces a 1-Lipschitz map
f
A
from the space Z
p
of
p
-adic integers to Z
p
. The ...map
f
A can naturally be plotted in a unit real square I
2
⊂ R
2
: To an
m
-letter non-empty word
v
= γ
m
-1
γ
m
-2
... γ0 there corresponds a number 0.
v
∈ R with base-
p
expansion 0.γ
m
-1
γ
m
-2
... γ0; so to every
m
-letter input word
w
= α
m
-1
α
m
-2
··· α0 of A and to the respective
m
-letter output word a(
w
) = β
m
-1
β
m
-2
··· β0 of A there corresponds a point (0.
w
; 0.a(
w
)) ∈ R
2
. Denote
P
(A) a closure of the point set (0.
w
; 0.a(
w
)) where
w
ranges over all non-empty words.We prove that once some points of
P
(A) constitute a
C
2
-smooth curve in R
2
, the curve is a segment of a straight line with a rational slope. Moreover, when identifying
P
(A) with a subset of a 2-dimensional torus T
2
∈ R
3
, the smooth curves from
P
(A) constitute a collection of torus windings which can be ascribed to complex-valued functions
ψ
(
x, t
) =
e
i
(
Ax-2πBt
)
(
x, t
∈ R), i.e., to matter waves. As automata are causal discrete systems, the main result may serve a mathematical reasoning why wave phenomena are inherent in quantum systems: This is just because of causality principle and discreteness of matter.
The stability of robot-mower motion in a specific direction is considered. The direction is regulated by means of an angular sensor and a programmable controller adjusting the motor power at one of ...the two drive wheels. For mower motion over a flat surface, the maximum control ratio in the drive at each of those wheels depends on the direction of initial chassis rotation.
—
High or ultrahigh vacuum must be provided in new accelerating facilities with wide-aperture vacuum systems, such as FAIR (Darmstadt, Germany) and NICA (Dubna, Russia). One of the problems ...encountered while designing such systems is the selection of vacuum-tight connections and gasket types. The use of an ISO-K flange with a spring metallic C-shaped seal is considered the most promising possible variant of a detachable vacuum joint in comparison with the COF, ConFlat, or flat VATSeal flanges.
—It is shown that the class of all
C
2
-smooth real functions that can be computed (in a new, but natural sense precisely defined below) on Mealy machines (letter-to-letter transducers or, briefly, ...transducers) consists of affine functions only. Moreover, it turns out that all these functions can be naturally associated with wave functions of particles. Accordingly, this work can be regarded as a mathematical reasoning that the wave properties of quantum systems are caused by the discreteness of matter and causality, since transducers are a mathematical formalization of the law of causality.
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