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1.
Bo Zhang Xiang Liu Wei-Zhen Deng Shi-Lin Zhu 《The European Physical Journal C - Particles and Fields》2007,50(3):617-628
Recently the Babar Collaboration reported a new cs̄ state, DsJ(2860), and the Belle Collaboration observed DsJ(2715). We investigate the strong decays of the excited cs̄ states using the 3
P
0 model. After comparing the theoretical decay widths and decay patterns with the available experimental data, we are inclined
to conclude that: (1) DsJ(2715) is probably the 1-(13
D
1) cs̄ state, although the 1-(23
S
1) assignment is not completely excluded; (2) DsJ(2860) seems unlikely to be the 1-(23
S
1) and 1-(13
D
1) candidate; (3) to consider DsJ(2860) either as a 0+(23
P
0) or as a 3-(13
D
3) cs̄ state is consistent with the experimental data; (4) the experimental search of DsJ(2860) in the channels Dsη, DK*, D*K and Ds
*η will be crucial to distinguish the above two possibilities.
PACS 13.25.Ft; 12.39.-x 相似文献
2.
Zhi-Gang Wang 《The European Physical Journal C - Particles and Fields》2008,56(2):181-187
In this article, we calculate the strong coupling constants gBs0Bsη and gBs1B*sη with the light-cone QCD sum rules. Then we take into account the small η–π0 transition matrix according to Dashen’s theorem, and we obtain the small decay widths for the isospin violation processes
Bs0→Bsη→Bsπ0 and Bs1→Bs
*η→Bs
*π0. We can search the strange-bottomed (0+,1+) mesons Bs0 and Bs1 in the invariant Bsπ0 and B*
sπ0 mass distributions, respectively.
PACS 12.38.Lg; 13.25.Hw; 14.40.Nd 相似文献
3.
Masses of the Ds(0^±) mesons are investigated from a view-point of ordinary light-heavy system in the framework of the Gaussian sum rules, which are worked out by means of the Laplacian transformation to the usual Borel sum rules. Using the standard input of QCD non-perturbative parameters, the corresponding mass spectra and couplings of the currents to the Ds(0^±) mesons are obtained. Our results are mDs(0-) = 1.968±0.016±0.003 GeV and mDs(0+) = 2.320 ±0.014 ± 0.003 GeV, which are in good accordance with the experimental data, 1.969 GeV and 2.317 GeV. 相似文献
4.
X. Liu Y.-M. Yu S.-M. Zhao X.-Q. Li 《The European Physical Journal C - Particles and Fields》2006,47(2):445-452
Based on the assumption that DsJ
*(2317) and DsJ(2460) are the (0+,1+) chiral partners of Ds and D*
s, we evaluate the strong pionic and radiative decays of DsJ
*(2317) and DsJ(2460) in the constituent quark meson (CQM) model. Our numerical results of the relative ratios of the decay widths are reasonably
consistent with the data.
PACS 13.25.Ft; 12.38.Lg; 12.39.Fe; 12.39.Hg 相似文献
5.
D.S. Baranov G.G. Volkov S.S. Gershtein A.A. Ivanilov V.I. Konyushko V.M. Korabliev V.A. Korotkov E.P. Kuznetsov V.V. Makeev Yu.P. Nikitin S.N. Parshikura A.Yu. Polyarush Yu.G. Rjabov Yu.I. Smirnov A.A. Sokolov V.A. Yarba 《Physics letters. [Part B]》1977,70(2):269-272
In the SKAT bubble chamber neutrino experiment production of a short-living neutral particle with mass (1.4?m?2.5) GeV/c2 and lifetime τ≈6×10?12 s has been detected. The event may be interpreted as production and decay of the heavy lepton M0→μ?+e++νe with mass (1.4?mM0?2.1) GeV/c2. It might also be the production of a charmed particle D0→e++τ?+νe (D0→e++π?+νe) with mass 1.4?mD0?2.5) GeV/c2 in a non-diagonal neutral current. The probability to interpret the event as other possible processes is very low. 相似文献
6.
《The European Physical Journal C - Particles and Fields》2007,51(2):301-315
Diffractive photoproduction of D*±(2010) mesons was measured with the ZEUS detector at the ep collider HERA, using an integrated luminosity of 78.6 pb-1. The D* mesons were reconstructed in the kinematic range: transverse momentum pT(D*) > 1.9 GeV and pseudorapidity |η(D*)|<1.6, using the decay D*+→D0π+
s followed by D0→K-π+(+c.c.). Diffractive events were identified by a large gap in pseudorapidity between the produced hadronic state and the outgoing
proton. Cross sections are reported for photon–proton centre-of-mass energies in the range 130 < W < 300 GeV and for photon
virtualities Q2 < 1 GeV2, in two ranges of the Pomeron fractional momentum xIP<0.035 and xIP<0.01. The relative contribution of diffractive events to the inclusive D*±(2010) photoproduction cross section is about 6%. The data are in agreement with perturbative QCD calculations based on various
parameterisations of diffractive parton distribution functions. The results are consistent with diffractive QCD factorisation. 相似文献
7.
E. Klempt M. Matveev A.V. Sarantsev 《The European Physical Journal C - Particles and Fields》2008,55(1):39-50
A Dalitz plot analysis of the OZI rule violating decay D+
s into π-π+π+ is presented using different partial wave approaches. Scalar and vector waves are described by K-matrices; their production
is parameterized in a P-vector approach. Alternatively, Breit–Wigner amplitudes and Flatté parametrization are used. Special
emphasis is devoted to scalar mesons. The f0(980) resonance provides the most significant contribution. Adding f0(1500) to the scalar wave leads to an acceptable fit while introduction of f0(1370) and/or f0(1710) does not lead to significant improvements. A scan of the scalar wave optimizes for M=1452 ± 22 MeV/c
2. When f0(1710) is added, the mass uncertainty increases, and the fit yields M=1470 ± 60 MeV/c
2 which is fully compatible with the nominal f0(1500) mass. The scalar wave seems to exhibit a phase motion of 270° units in the mass range from 1200 to 1650 MeV/c
2.
PACS 11.80.Et; 13.20.Fc; 14.40.Cs 相似文献
8.
Shu-Min Zhao Xiang Liu Shuang-Jiu Li 《The European Physical Journal C - Particles and Fields》2007,51(3):601-606
Assuming D*
sJ(2317) and DsJ(2460) to be the (0+,1+) chiral partners of the regular particles Ds(1968) and D*
s(2112), we calculate the semileptonic decays of Bs to Ds(1968), D*
s(2112), DsJ
*(2317) and DsJ(2460) in terms of the constituent quark meson model. The large branching ratios of the semileptonic decays of Bs to DsJ
*(2317) and DsJ(2460) indicate that these two semileptonic decays should be seen in future experiments.
PACS 12.25.Ft; 12.38.Lg; 12.39.Fe; 12.39.Hg 相似文献
9.
We report the results of the Monte Carlo study of the method to determine the CKM angle φ3 using Dalitz plot analysis of D0 produced in B±→DK± decay. Our main goal is to find the optimal strategy for a model-independent φ3 extraction. We find that the analysis using decays of CP-tagged D mesons only cannot provide a completely model-independent
measurement in the case of a limited data sample. The procedure involving binned analysis of B±→DK± and ψ(3770)→(K0
Sπ+π-)D(K0
Sπ+π-)D decays is proposed which, in contrast, allows not only to reach the φ3 precision comparable to an unbinned model-dependent fit, but also provides an unbiased measurement with currently available
data.
PACS 11.30.Er; 12.15.Hh 相似文献
10.
Zhen-Jun Xiao Xin-Fen Chen Dong-Qin Guo 《The European Physical Journal C - Particles and Fields》2007,50(2):363-371
In this paper, we calculate the branching ratios and CP-violating asymmetries for Bs→ρ±K∓, ρ0K̄0 and ωK̄0 decays in the perturbative QCD factorization approach. The theoretical predictions for the CP-averaged branching ratios of
the considered decays are Br(Bs→ρ±K∓)≈24.7×10-6, Br(Bs→ρ0K̄0)≈1.2×10-7 and Br(Bs→ωK̄0)≈1.7×10-7; and we also predict large CP-violating asymmetries for the considered decay modes. Specifically, the large ACP
dir(Bs→ρ±K∓) at -12% level plus large branching ratio at 10-5 level are measurable in the forthcoming LHC-b experiments.
PACS 13.25.Hw; 12.38.Bx; 14.40.Nd 相似文献
11.
12.
O. P. Yushchenko V. F. Kurshetsov A. P. Filin S. A. Akimenko A. V. Artamonov A. M. Blik V. V. Brekhovskikh V. S. Burtovoy S. V. Donskov A. V. Inyakin A. M. Gorin G. V. Khaustov S. A. Kholodenko V. N. Kolosov A. S. Konstantinov V. M. Leontiev V. A. Lishin M. V. Medynsky Yu. V. Mikhailov V. F. Obraztsov V. A. Polyakov A. V. Popov V. I. Romanovsky V. I. Rykalin A. S. Sadovsky V. D. Samoilenko V. K. Semenov O. V. Stenyakin O. G. Tchikilev V. A. Uvarov V. A. Duk S. N. Filippov E. N. Guschin Yu. G. Kudenko A. A. Khudyakov V. I. Kravtsov A. Yu. Polyarush V. N. Bychkov G. D. Kekelidze V. M. Lysan B. Zh. Zalikhanov 《JETP Letters》2018,107(3):139-142
Recent results from OKA setup concerning form factor studies in Ke3 decay are presented. About 5.25 M events obtained for decays of 17.7 GeV/cK+ are selected for the analysis. The linear and quadratic slopes for the decay form factor f+(t) are measured: λ'+ = 2.95 ± 0.022 ± 0.018 × 10 -2 for the linear slope fit and λ+ = 2.611 ± 0.035 ± 0.028 × 10 -2, λ"+ = 1.91 ± 0.19 ± 0.14 × 10 -3 for the quadratic one. The scalar and tensor contributions are compatible with zero. Several alternative parametrizations are tried: the Pole fit parameter is found to be M V = 891 ± 3 MeV; the parameter of the dispersive parametrization is measured to be Λ+ = 2.458 ± 0.018 × 10-2. 相似文献
13.
The (4, 4*) ⊕ (4*, 4) model of broken chiral SU (4) × SU (4) symmetry has been used to calculate the third-order coupling
constants involving charmed and ordinary pseudoscalar mesons. These coupling constants are exploited to derive some interesting
new relations among the masses and decay constants of these charmed particles. Using the known masses and decay constants
as inputs, we exploit these relations to predict:F
D = −1·41F
π
,F
F = −1·13F
π
,F
D/FF = 1·25,m(D
s) = 1·43 GeV,m(F
s) = 1·39 GeV andm(K
s) = 1·02 GeV. 相似文献
14.
H. Cherkani-Hassani S. Cherkani-Hassani D. S. Belic J. J. Jureta J. Lecointre P. Defrance 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,58(1):75-83
Absolute cross-sections for electron-impact ionization and dissociation of
C2H2+ and C2D2+ have been measured for electron energies
ranging from the corresponding thresholds up to 2.5 keV. The animated
crossed beams experiment has been used. Light as well as heavy fragment ions
that are produced from the ionization and the dissociation of the target
have been detected for the first time. The maximum of the cross-section for
single ionization is found to be (5.56 ± 0.03)× 10-17 cm2 around 140 eV. Cross-sections for dissociation of C2
H2+ (C2D2+) to ionic products are seen to decrease for two orders
of magnitude, from C2D+ (12.6 ± 0.3) × 10-17 cm2 over CH+(9.55 ± 0.06) × 10-17 cm2,
C+ (6.66 ± 0.05) × 10-17 cm2, C2+ (5.36 ± 0.27) × 10-17 cm2, H+ (4.73 ±
0.29) × 10-17 cm2 and CH2+ (4.56 ± 0.27) × 10-18 cm2 to H2+ (5.68 ± 0.49) ×
10-19 cm2. Absolute
cross-sections and threshold energies have been compared with the scarce
data available in the literature. 相似文献
15.
Yu-Ming Wang Hao Zou Zheng-Tao Wei Xue-Qian Li Cai-Dian Lü 《The European Physical Journal C - Particles and Fields》2008,54(1):107-121
Within the standard model, we investigate the semi-leptonic weak decays of J/ψ. The various form factors of J/ψ making the
transition to a single charmed meson (D(*)
(d,s)) are studied in the framework of QCD sum rules. These form factors fully determine the rates of the weak semi-leptonic decays
of J/ψ and provide valuable information on non-perturbative QCD effects. Our results indicate that the decay rate of the semi-leptonic
weak decay mode J/ψ→D(*)-
s+e++νe is at the order of 10-10.
PACS 13.20.Gd; 13.25.Gv; 11.55.Hx 相似文献
16.
M. Ablikim M. N. Achasov X. C. Ai O. Albayrak M. Albecht D. J. Ambrose A. Amoroso 《中国物理C(英文版)》2016,40(11):113001-113001
By analyzing 2.93 fb-1 data collected at the center-of-mass energy √s=3.773 GeV with the BESIII detector, we measure the absolute branching fraction of the semileptonic decay D+→K0e+ve to be B(D+→K0e+ve)=(8.59±0.14±0.21)% using K0→KS0→π0π0, where the first uncertainty is statistical and the second systematic. Our result is consistent with previous measurements within uncertainties.. 相似文献
17.
Ye.S. Golubeva W. Cassing L.A. Kondratyuk 《The European Physical Journal A - Hadrons and Nuclei》2002,14(2):255-263
We study the perspectives of resonant and nonresonant charmed-meson production in ˉp + A reactions within the Multiple Scattering Monte Carlo (MSMC) approach. We calculate the production of the resonances Ψ(3770),Ψ(4040)
and Ψ(4160) on various nuclei, their propagation and decay to D,ˉD, D
*,ˉD*, D
s,ˉDs in the medium and vacuum, respectively. The modifications of the open charm vector mesons in the nuclear medium are found
to be rather moderate or even small such that dilepton spectroscopy will require an invariant mass resolution of a few MeV.
Furthermore, the elastic and inelastic interactions of the open charm mesons in the medium are taken into account, which can
be related to (u, d )-, s- or c-quark exchange with nucleons. It is found that by studying the D/ˉD ratio for low momenta in the laboratory ( ? 2 - 2.2 GeV/c) as a function of the target mass A stringent constraints on the c-quark exchange cross-section can be obtained. On the other hand, the ratios D
-
s/D
+
s as well as D/D
-
s and D/D
+
s at low momenta as a function of A will permit to fix independently the strength of the s-quark exchange reaction in D
-
s
N scattering.
Received: 1 March 2002 / Accepted: 21 March 2002 相似文献
18.
Yu-Ming Wang Hao Zou Zheng-Tao Wei Xue-Qian Li Cai-Dian Lü 《The European Physical Journal C - Particles and Fields》2008,55(4):607-613
In our previous study, we calculated the transition form factors of J/ψ→D(*)
(s) using the QCD sum rules. Based on the factorization approximation, the form factors obtained can be applied to evaluate the
weak non-leptonic decay rates of J/ψ→D(*)
(s)+M, where M stands for a light pseudoscalar or vector meson. We predict that the branching ratio for inclusive non-leptonic
two-body weak decays of J/ψ, which are realized via the spectator mechanism, can be as large as 1.3×10-8; in particular, the branching ratio of J/ψ→D*±
s+ρ∓ can reach 5.3×10-9. Such values will be marginally accessed by the ability of BESIII, which will begin running very soon.
PACS 13.20.Gd; 13.25.Gv 相似文献
19.
V. P.S. Awana A. Vajpayee M. Mudgel V. Ganesan A. M. Awasthi G. L. Bhalla H. Kishan 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,62(3):281-294
We report synthesis, structure/micro-structure, resistivity under magnetic
field [ρ(T)H], Raman spectra, thermoelectric power S(T), thermal conductivity
κ(T), and magnetization of ambient pressure argon annealed
polycrystalline bulk samples of MgB2, processed under identical
conditions. The compound crystallizes in hexagonal structure with space
group P6/mmm. Transmission electron microscopy (TEM) reveals electron micrographs
showing various types of defect features along with the presence of 3–4 nm
thick amorphous layers forming the grain boundaries of otherwise crystalline
MgB2. Raman spectra of the compound at room temperature exhibited
characteristic phonon peak at 600 cm-1. Superconductivity is observed
at 37.2 K by magnetic susceptibility χ(T), resistivity ρ(T), thermoelectric power
S(T), and thermal conductivity κ(T) measurements. The power law fitting
of ρ(T) give rise to Debye temperature (ΘD) at 1400 K which is
found consistent with the theoretical fitting of S(T), exhibiting Θ
D of 1410 K and carrier density of 3.81 × 1028/m3. Thermal
conductivity κ(T) shows a jump at 38 K, i.e., at Tc, which was
missing in some earlier reports. Critical current density (Jc) of up to
105 A/cm2 in 1–2 T (Tesla) fields at temperatures (T) of up to 10 K
is seen from magnetization measurements. The irreversibility field, defined
as the field related to merging of M(H) loops is found to be 78, 68 and 42 kOe
at 4, 10 and 20 K respectively. The superconducting performance parameters
viz. irreversibility field (Hirr) and critical current density
Jc(H) of the studied MgB2 are improved profoundly with addition of
nano-SiC and nano-diamond. The physical property parameters measured for
polycrystalline MgB2 are compared with earlier reports and a
consolidated insight of various physical properties is presented. 相似文献
20.
H. Cherkani-Hassani D. S. Belic J. J. Jureta J. Lecointre P. Defrance 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,58(1):85-94
Absolute cross-sections for electron-impact dissociative ionization of C2
H2+ and C2 D2+ to CH+, C+, C2+ , H+, CH2+
and C2D+ fragments are determined for electron energies ranging
from the corresponding threshold to 2.5 keV. Results obtained in a crossed
beams experiment are analyzed to estimate the contribution of dissociative
ionization to each fragment formation. The dissociative ionization cross
sections are seen to decrease for more than an order of magnitude, from
CH+ (5.37±0.10) × 10-17 cm2 over C+ (4.19±
0.16) × 10-17 cm2, C2D+ (3.94±0.38) ×
10-17 cm2, C2+ (3.82±0.15) × 10-17 cm2
and H+ (3.37±0.21) × 10-17 cm2 to CH2+
(2.66±0.14) × 10-18 cm2. Kinetic energy release
distributions of fragment ions are also determined from the analysis of the
product velocity distribution. Cross section values, threshold energies and
kinetic energies are compared with the data available from the literature.
Conforming to the scheme used in the study of the dissociative excitation of
C2H2+
( C2 D2+ )\left( {\rm C}_2 {\rm D}_2^+ \right), the cross-sections are presented in
a format suitable for their implementation in plasma simulation codes. 相似文献