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R. R. Akhmetshin,
V. M. Aulchenko,
V. Sh. Banzarov,
L. M. Barkov,
S. E. Baru, N. S. Bashtovoy,
A. E. Bondar,
A. V. Bragin,
S. I. Eidelman,
D. A. Epifanov, [......],
A. S. Popov,
S. I. Redin,
A. A. Ruban,
N. M. Ryskulov,
Yu. M. Shatunov,
B. A. Shwartz,
A. L. Sibidanov,
I. G. Snopkov,
E P Solodov,
Yu. V. Yudin
[show abstract]
[hide abstract]
ABSTRACT: The $\phi$(1020) meson leptonic width has been determined from the combined
analysis of 4 major decay modes of the resonance ($\phi\to K^+
K^-,K^0_LK^0_S,\pi^+\pi^-\pi^0,\eta\gamma$) studied with the CMD-2 detector at
the VEPP-2M $e^+e^-$ collider. The following value has been obtained:
$\Gamma(\phi\to e^+e^-) = 1.235\pm 0.006\pm 0.022$ keV.
The $\phi(1020)$ meson parameters in four main decay channels have been also
recalculated: $B(\phi\to K^+K^-) = 0.493\pm 0.003\pm 0.007$, $B(\phi\to K_LK_S)
= 0.336\pm 0.002\pm 0.006$, $B(\phi\to\pi^+\pi^-\pi^0) = 0.155\pm 0.002\pm
0.005$, $B(\phi\to\eta\gamma) = 0.0138\pm 0.0002\pm 0.0002$.
10/2010;
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CMD-2 Collaboration: R. R. Akhmetshin,
V. M. Aulchenko,
V. Sh. Banzarov,
L. M. Barkov,
S. E. Baru, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin,
S. I. Eidelman, [......],
A. S. Popov,
S. I. Redin,
A. A. Ruban,
N. M. Ryskulov,
Yu. M. Shatunov,
B. A. Shwartz,
A. L. Sibidanov,
I. G. Snopkov,
E P Solodov,
Yu. V. Yudin
[show abstract]
[hide abstract]
ABSTRACT: The process e+ e- -> phi -> K+ K- has been studied with the CMD-2 detector using about 542 000 events detected in the center-of-mass energy range from 1.01 to 1.034 GeV. The systematic error of the cross section is estimated to be 2.2%. The phi(1020) meson parameters in the phi -> K+K- decay channel have been measured: sigma_0(phi-> K+K-) = 2016 +- 8 +- 44 nb, m(phi) = 1019.441 +- 0.008 +- 0.080 MeV/c2, Gamma(phi) = 4.24 +- 0.02 +- 0.03 MeV, B(e+e-)B(K+K-) = (14.27 +- 0.05 +- 0.31)*10(-5).
05/2008;
-
Physics Letters B - PHYS LETT B. 01/2008; 669:217-222.
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The CMD-2 Collaboration: R. R. Akhmetshin,
V. M. Aulchenko,
V. Sh. Banzarov,
L. M. Barkov, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin,
S K Dhawan,
S. I. Eidelman, [......],
A. L. Sibidanov,
V. A. Sidorov,
A. N. Skrinsky,
V.P. Smakhtin,
I. G. Snopkov,
E P Solodov,
J. A. Thompson,
Yu. V. Yudin,
A. S. Zaitsev,
S. G. Zverev
[show abstract]
[hide abstract]
ABSTRACT: We present a measurement of the pion form factor based on e+e- annihilation data from the CMD-2 detector in the energy range 0.6<sqrt(s)<1.0 GeV with a systematic uncertainty of 0.8%. A data sample is five times larger than that used in our previous measurement.
11/2006;
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R. R. Akhmetshin,
V. M. Aulchenko,
V. Sh. Banzarov,
L. M. Barkov, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin,
S K Dhawan,
S. I. Eidelman, [......],
A. L. Sibidanov,
V. A. Sidorov,
A. N. Skrinsky,
V.P. Smakhtin,
I. G. Snopkov,
E P Solodov,
J. A. Thompson,
Yu. V. Yudin,
A. S. Zaitsev,
S. G. Zverev
[show abstract]
[hide abstract]
ABSTRACT: The cross section of the process e+e- -> pi+pi- has been measured at the CMD-2 detector in the 370-520 MeV center-of-mass (c.m.) energy range. A systematic uncertainty of the measurement is 0.7 %. Using all CMD-2 data on the pion form factor, the pion electromagnetic radius was calculated. The cross section of muon pair production was also determined.
11/2006;
-
R. R. Akhmetshin,
V. M. Aulchenko,
V. Sh. Banzarov,
L. M. Barkov, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin,
S. I. Eidelman,
D. A. Epifanov, [......],
B. A. Shwartz,
A. L. Sibidanov,
V. A. Sidorov,
A. N. Skrinsky,
V. P. Smakhtin,
I. G. Snopkov,
E. P. Solodov,
Yu. V. Yudin,
A. S. Zaitsev,
S. G. Zverev
[show abstract]
[hide abstract]
ABSTRACT: The cross section of the process
ee→πππ
has been measured in the c.m. energy range 984 1060 MeV with the CMD-2
detector at the VEPP-2M collider. The obtained value of
Br(ϕ→ee)Br(ϕ→πππ)=(4.51±0.16±0.11)×10
is in good agreement with the previous measurements and has the best
accuracy. Analysis of the Dalitz plot was performed. The contributions
of the dominant ϕ→ρπ mechanism as well as of a small
direct ϕ→3π amplitude were determined.
Physics Letters B 10/2006; 642:203-209. · 3.95 Impact Factor
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Physics Letters B - PHYS LETT B. 01/2006; 642(3):203-209.
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M.N. Achasov,
R.R. Akhmetshin,
V.M. Aulchenko,
V.Sh. Banzarov,
A. Baratt,
L.M. Barkov,
S.E. Baru, N.S. Bashtovoy,
K.I. Beloborodov,
A.V. Berdugin, [......],
A.N. Skrinsky,
I.G. Snopkov,
E.P. Solodov,
J.A. Thompson,
Y.V. Usov,
A.A. Valishev,
A.V. Vasiljev,
Y.V. Yudin,
A.S. Zaitsev,
S.G. Zverev
[show abstract]
[hide abstract]
ABSTRACT: The Cryogenic Magnetic Detector(CMD-2) and Spherical Neutral Detector(SND) operated at the VEPP-2M electron-positron collider in the c.m. energy range 360-1380MeV. The total integrated luminosity above 60pb–1 has been collected by both detectors. The cross sections of hadronic production have been measured with high precision. New results for the light vector meson parameters and rare decay mode were obtained.PACS: 13.66.Bc Hadron production in e–e+ interactions – 13.66.Jn Precision measurements in e–e+ interactions
European Physical Journal C 06/2004; 33:s583-s585. · 3.63 Impact Factor
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R. R. Akhmetshin,
V. M. Aulchenko,
V. Sh. Banzarov,
A. Baratt,
L. M. Barkov,
S. E. Baru, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin,
S. I. Eidelman,
D. A. Epifanov
[show abstract]
[hide abstract]
ABSTRACT: The cross section of the process e+e--->pi0pi0gamma has been measured in the c.m. energy range 600-970 MeV with the CMD-2 detector. The following branching ratios have been determined: B(rho0-->pi0pi0gamma)=(5.2+1.5-1.3+/-0.6)×10-5 and B(omega-->pi0pi0gamma)=(6.4+2.4-2.0+/-0.8)×10-5. Evidence for the rho0-->f0(600)gamma decay has been obtained: B(rho0-->f0(600)gamma)=(6.0+3.3-2.7+/-0.9)×10-5. From a search for the process e+e--->etapi0gamma the following upper limit has been obtained: B(omega-->etapi0gamma)
Physics Letters B - PHYS LETT B. 01/2004; 580:119-128.
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R. R. Akhmetshin,
V. M. Aulchenko,
V. Sh. Banzarov,
A. Baratt,
L. M. Barkov,
S. E. Baru, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin,
S. I. Eidelman,
D. A. Epifanov
[show abstract]
[hide abstract]
ABSTRACT: The cross section of the process e+e--->omegapi0-->pi0pi0gamma has been measured in the c.m. energy range 920-1380 MeV with the CMD-2 detector. Its energy dependence is well described by the interference of the /rho(770) and /rho(1450) mesons decaying to omegapi0. Upper limits for the cross sections of the direct processes e+e--->pi0pi0gamma,etapi0gamma have been set.
Physics Letters B - PHYS LETT B. 01/2003; 562:173-181.
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E. V. Anashkin,
V. M. Aulchenko,
R. R. Akhmetshin,
V. Sh. Banzarov,
L. M. Barkov,
S. E. Baru, N. S. Bashtovoy,
D. V. Bondarev,
A. E. Bondar,
A. V. Bragin, [......],
J. A. Thompson,
G. V. Fedotovich,
B. I. Khazin,
W. V. Hughes,
D. V. Chernyak,
A. G. Shamov,
Yu. M. Shatunov,
B. A. Shwartz,
S. I. Eidelman,
Yu. V. Yudin
[show abstract]
[hide abstract]
ABSTRACT: The cross section for the process e
+
e
− → K
L
0
K
S
0
is measured by using approximately 1000 events recorded by the CMD-2 detector at the VEPP-2M collider in the energy range
from 1.05 to 1.38 GeV.
Physics of Atomic Nuclei 06/2002; 65(7):1222-1227. · 0.57 Impact Factor
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R. R. Akhmetshin,
E. V. Anashkin,
V. M. Aulchenko,
V. Sh. Banzarov,
L. M. Barkov,
S. E. Baru, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin, [......],
V. P. Smakhtin,
I. G. Snopkov,
E. P. Solodov,
P. Yu. Stepanov,
A. I. Sukhanov,
J. A. Thompson,
V. M. Titov,
A. A. Valishev,
Yu. V. Yudin,
S. G. Zverev
[show abstract]
[hide abstract]
ABSTRACT: The Cryogenic Magnetic Detector (CMD‐2) and main it’s parameters are shortly described. The results for the cross sections of e+e− annihilation into hadrons are presented in the c.m. energy range from 0.37 to 1.39 GeV. The total integrated luminosity of about 31 pb−1 has been collected. The new results for the ρ and ω meson parameters were obtained. The pion form factor was determinated with a 0.6% systematic uncertainty. The major decay modes of the ϕ meson as well as multihadron final states have been studied in a broad energy range. © 2002 American Institute of Physics
AIP Conference Proceedings. 06/2002; 619(1):15-29.
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R. R. Akhmetshin,
E. V. Anashkin,
M. Arpagaus,
V. M. Aulchenko,
V. S. Banzarov,
L. M. Barkov,
S. E. Baru, N. S. Bashtovoy,
D. V. Chernyak,
A. E. Bondar, [......],
V. A. Sidorov,
A. N. Skrinsky,
V. P. Smakhtin,
I. G. Snopkov,
E. P. Solodov,
P. Y. Stepanov,
A. I. Sukhanov,
Y. V. Yudin,
S. G. Zverev,
J. A. Thompson
Physics Letters B 04/2001; 508:217-218. · 3.95 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: This paper describes the superconducting magnet system of the
CMD-2 detector. The magnetic field is provided by the main and two
compensating superconducting solenoids. The unique features of this
system are the solenoids protection method utilizing a distributed
resistance along the coil and the power supply being a fluxpump type.
The main solenoid produces a field up to 1.2 T in a volume of φ 0.71
m×0.9 m. Its radiation thickness and E/M ratio are 0.38 X<sub>0
</sub> and 5 kJ/kg, respectively. NbTi/Cu superconducting cables without
any insulation and an aluminum stabilizer were used for the design of
solenoid coils. The superconducting cable was wound in a stainless-steel
bobbin and soldered by a PbSn alloy. The cooling bath provides a
temperature of 4.2 K in the system. The superconducting magnet system of
the CMD-2 detector was manufactured and tested in 1989
IEEE Transactions on Appiled Superconductivity 01/2000; · 1.04 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: A superconducting rectifier fluxpump has been used for the dc
power supply of the magnet system of the CMD-2 detector on the VEPP-2M
collider at the Budker Institute of Nuclear Physics in Russia since
1989. The fluxpump provides a complete pumping cycle: charging the
magnet system, stabilization of the magnetic field, and discharging. The
fluxpump consists of an air-core current step-up superconducting
transformer and two groups of thermally controlled superconducting
switches arranged as a fullwave rectifier. Critical output current
during the test was 5.4 kA. The accuracy of the field stabilization
provided by the fluxpump is 2.5·10<sup>-5</sup>. The fluxpump has
exhibited reliable and safe operation during its entire history of use
IEEE Transactions on Appiled Superconductivity 10/1999; · 1.04 Impact Factor
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R. R. Akhmetshin,
E. V. Anashkin,
M. Arpagaus,
V. M. Aulchenko,
V. S. Banzarov,
L. M. Barkov, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin,
D. V. Chernyak,
A. S. Dvoretsky
[show abstract]
[hide abstract]
ABSTRACT: Radiative decays of the φ meson have been studied using a data sample of about 19 million φ decays collected by the CMD-2 detector at VEPP-2M collider in Novosibirsk. From selected e+e−→π0π0γ and e+e−→ηπ0γ events the following model independent results have been obtained: Br(φ→π0π0γ)=(0.92±0.08±0.06)×10−4 for Mπ0π0>700 MeV, Br(φ→ηπ0γ)=(0.90±0.24±0.10)×10−4. It is shown that the intermediate mechanism f0(980)γ dominates in the φ→π0π0γ decay and the corresponding branching ratio is Br(φ→f0(980)γ)=(2.90±0.21±1.54)×10−4. The systematic error is dominated by the possible model uncertainty. Using the same data sample the upper limit has been obtained for the P- and CP-violating decay of η at 90% CL: Br(η→π0π0)
Fuel and Energy Abstracts 01/1999; 462(3):380-388.
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R. R. Akhmetshin,
E. V. Anashkin,
M. Arpagaus,
V. M. Aulchenko,
V. Sh. Banzarov,
L. M. Barkov, N. S. Bashtovoy,
A. E. Bondar,
D. V. Bondarev,
A. V. Bragin,
D. V. Chernyak,
A. G. Chertovskikh
[show abstract]
[hide abstract]
ABSTRACT: The 5.8 pb−1 of data collected by the CMD-2 Collaboration in the energy range 1.05–1.38 GeV have been used to study energy dependence of the processes e+e−→π+π−2π0 and e+e−→2π+2π−. Analysis of the differential distributions demonstrates the dominance of the a1(1260)π and ωπ intermediate states. Upper limits for the contributions of other possible states are also obtained.
Physics Letters B - PHYS LETT B. 01/1999; 466(2):392-402.
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R. R. Akhmetshin,
G. A. Aksenov,
V. A. Astakhov,
E. V. Anashkin,
M. Arpagaus,
V. M. Aulchenko,
V. S. Banzarov,
L. M. Barkov,
S. E. Baru, N. S. Bashtovoy, [......],
I. G. Snopkov,
E. P. Solodov,
P. Yu. Stepanov,
A. I. Sukhanov,
Yu. Y. Yudin,
S. G. Zverev,
D. H. Brown,
B. L. Roberts,
J. A. Thompson,
V. W. Hughes
[show abstract]
[hide abstract]
ABSTRACT: The general purpose detector CMD-2 at the VEPP-2M electron-positron collider at Novosibirsk has collected about 11 pb−1 of integrated luminosity in the center-of-mass energy range from 0.36 up to 1.38 GeV. Data in the ρ-meson energy range from 0.61 to 0.96 GeV have been analysed and preliminary results on the e+e−→π+π− cross-section in this energy range are presented. © 1998 American Institute of Physics.
AIP Conference Proceedings. 05/1998; 432(1):787-792.
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R.R. Akhmetshin,
E.V. Anashkin,
V.M. Aulchenko,
V.Sh. Banzarov,
A. Baratt,
L.M. Barkov,
S.E. Baru, N.S. Bashtovoy,
A.E. Bondar,
D.V. Bondarev, [......],
A.N. Skrinsky,
V.P. Smakhtin,
I.G. Snopkov,
E.P. Solodov,
P.Yu. Stepanov,
A.I. Sukhanov,
J.A. Thompson,
A.A. Valishev,
Yu.V. Yudin,
S.G. Zverev
[show abstract]
[hide abstract]
ABSTRACT: The cross section of the process e+e−→ηγ has been measured in the 600–1380 MeV c.m. energy range with the CMD-2 detector. The following branching ratios have been determined: B(ρ→ηγ)=(3.28±0.37±0.23)×10−4, B(ω→ηγ)=(5.10±0.72±0.34)×10−4, B(φ→ηγ)=(1.287±0.013±0.063)×10−2. Evidence for the ρ(1450)→ηγ decay has been obtained for the first time.
Physics Letters B.
-
R.R. Akhmetshin,
E.V. Anashkin,
M. Arpagaus,
V.M. Aulchenko,
V.Sh. Banzarov,
L.M. Barkov, N.S. Bashtovoy,
A.E. Bondar,
D.V. Bondarev,
A.V. Bragin, [......],
V.P. Smakhtin,
I.G. Snopkov,
E.P. Solodov,
P.Yu. Stepanov,
A.I. Sukhanov,
J.A. Thompson,
V.M. Titov,
A.A. Valishev,
Yu.V. Yudin,
S.G. Zverev
[show abstract]
[hide abstract]
ABSTRACT: Using 11.6 pb−1 of data collected in the energy range 0.984–1.06 GeV by CMD-2 at VEPP-2M, the cross section of the reaction e+e−→π+π−π+π− has been studied. For the first time an interference pattern was observed in the energy dependence of the cross section near the φ meson. The branching ratio of the φ→π+π−π+π− decay double suppressed by the G-parity and OZI rule is measured Br(φ→π+π−π+π−)=(3.93±1.74±2.14)×10−6. The upper limits have been placed for the decays φ→π+π−π+π−π0 and φ→ηπ+π−, .
Physics Letters B. 491:81-89.