The KEDR experiment, which started in 2002, is dedicated to a study of c- and b-quarks and the two-photon physics at the e + e − collider VEPP-4M in the Budker INP. To analyze the 2γ data and ...estimate contribution of two-photon background events in the 1 data samples, the event generators e + e − → e + e − + hadrons, e + e − → e + e − + π + π −, and e + e − → e + e − + PS (PS - pseudoscalar meson) have been developed.
Measurement of Γee(J/ψ) with KEDR detector Anashin, V. V; Aulchenko, V. M; Baldin, E. M ...
The journal of high energy physics,
05/2018, Letnik:
2018, Številka:
5
Journal Article
Recenzirano
Odprti dostop
A
bstract
The product of the electronic width of the
J/ψ
meson and the branching fractions of its decay to hadrons and electrons has been measured using the KEDR detector at the VEPP-4M
e
+
e
−
...collider. The obtained values are
Γ
e
e
J
/
ψ
=
5.550
±
0.056
±
0.089
keV
,
Γ
e
e
J
/
ψ
·
ℬ
hadrons
J
/
ψ
=
4.884
±
0.048
±
0.078
keV
,
Γ
e
e
J
/
ψ
·
ℬ
e
e
J
/
ψ
=
0.3331
±
0.0066
±
0.0040
keV
.
The uncertainties shown are statistical and systematic, respectively. Using the result presented and the world-average value of the electronic branching fraction, one obtains the total width of the
J/ψ
meson:
Γ
=
92.94
±
1.83
keV
.
These results are consistent with the previous experiments.
PID system based on focusing aerogel RICH for the super C-τ factory Barnyakov, A.Yu; Barnyakov, M.Yu; Boborovnikov, V.S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2020, Letnik:
952
Journal Article
Recenzirano
A high performance particle identification (PID) system is essential for the successful realization of the broad physics program at the future Super C-τ Factory in Novosibirsk. The main requirements ...for the PID system are as follows: good π/K-separation in the entire operational momentum range and good μ∕π-separation in the momentum range from 0.3 to 1.2 GeV/c. The RICH detector based on focusing aerogel radiator (FARICH) and position-sensitive photon detector meets all these requirements. The FARICH method is described, and the beam test results are presented. The FARICH system design outline for the Super C-τ Factory project is presented. Most promising photon detector options are considered.
The electronic width of the
J
/
ψ
meson and its product by the branching fractions of
J
/
ψ
meson decay to hadrons and electrons measured with the KEDR detector at the VEPP-4M
e
+
e
−
collider have ...been reported in ref. 1.
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
A
bstract
We present the study of the decay
J/ψ
→
ρπ
. The results are based on of 5.2 million
J/ψ
events collected by the KEDR detector at the VEPP-4M collider. The branching fractions are measured ...to be
B
(
J/ψ
→
ρπ
) = (2
.
072 ± 0
.
017 ± 0
.
062) ∙ 10
−
2
and
B
(
J/ψ
→
π
+
π
−
π
0
) = (1
.
878 ± 0
.
013 ± 0
.
051) ∙ 10
−
2
, where the first uncertainties are statistical and the second systematic. Our results are more precise than the previous relative measurements.
Using the KEDR detector at the VEPP-4M e+e− collider, we have determined the values of R at thirteen points of the center-of-mass energy between 1.84 and 3.05 GeV. The achieved accuracy is about or ...better than 3.9% at most of the energy points with a systematic uncertainty less than 2.4%.
Using the KEDR detector at the VEPP-4M e+e− collider, we have measured the values of Ruds and R at seven points of the center-of-mass energy between 3.12 and 3.72 GeV. The total achieved accuracy is ...about or better than 3.3% at most of energy points with a systematic uncertainty of about 2.1%. At the moment it is the most accurate measurement of R(s) in this energy range.
Using the 1.32
pb
-
1
statistics collected at the
J
/
ψ
peak with the KEDR detector at the VEPP-4M
e
+
e
-
collider, we measured the branching fractions of
J
/
ψ
meson decays to the final states 2(
π
...+
π
-
)
π
0
,
K
+
K
-
π
+
π
-
π
0
, 2(
π
+
π
-
)
and
K
+
K
-
π
+
π
-
. The results obtained for the decays
J
/
ψ
→
2(
π
+
π
-
)
π
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.
We present the analysis of all KEDR data on the determination of J/ψ and ψ(2S) masses. The data comprise six scans of J/ψ and seven scans of ψ(2S) which were performed at the VEPP-4M e+e− collider in ...2002–2008. The beam energy was determined using the resonance depolarization method. The detector and accelerator conditions during scans were very different that increases the reliability of the averaged results. The analysis accounts for partial correlations of systematic uncertainties on the masses. The following mass values were obtained:MJ/ψ=3096.900±0.002±0.006 MeV,Mψ(2S)=3686.099±0.004±0.009 MeV. These results supersede our previous measurements published in 2003 and 2012.
PDF
