共查询到20条相似文献,搜索用时 31 毫秒
1.
Alén B Fuster D Muñoz-Matutano G Martínez-Pastor J González Y Canet-Ferrer J González L 《Physical review letters》2008,101(6):067405
We study the metal-insulator transition in individual self-assembled quantum wires and report optical evidence of metallic liquid condensation at low temperatures. First, we observe that the temperature and power dependence of the single nanowire photoluminescence follow the evolution expected for an electron-hole liquid in one dimension. Second, we find novel spectral features that suggest that in this situation the expanding liquid condensate compresses the exciton gas in real space. Finally, we estimate the critical density and critical temperature of the phase transition diagram at n{c} approximately 1 x 10;{5} cm;{-1} and T{c} approximately 35 K, respectively. 相似文献
2.
Manfra MJ Hwang EH Das Sarma S Pfeiffer LN West KW Sergent AM 《Physical review letters》2007,99(23):236402
We present a study of the temperature and density dependence of the resistivity of an extremely high quality two-dimensional hole system grown on the (100) surface of GaAs. For high densities in the metallic regime (p > or approximately4x10;{9} cm;{-2}), the nonmonotonic temperature dependence ( approximately 50-300 mK) of the resistivity is consistent with temperature dependent screening of residual impurities. At a fixed temperature of T=50 mK, the conductivity versus density data indicate an inhomogeneity driven percolation-type transition to an insulating state at a critical density of 3.8x10;{9} cm;{-2}. 相似文献
3.
We performed optical spectroscopy measurement on a superconducting Ba0.6K0.4Fe2As2 single crystal with T{c}=37 K. Formation of the superconducting energy gaps in the far-infrared reflectance spectra below T{c} is clearly observed. A flat and close to unity reflectance is observed roughly below 150 cm;{-1} for Tor=T{c}. We determined the absolute value of the penetration depth at 10 K as lambda approximately 2000+/-80 A. A spectral weight analysis shows that the Ferrell-Glover-Tinkham sum rule is satisfied at low energy scale, less than 6Delta. 相似文献
4.
Akutsu T Kawamura S Nishizawa A Arai K Yamamoto K Tatsumi D Nagano S Nishida E Chiba T Takahashi R Sugiyama N Fukushima M Yamazaki T Fujimoto MK 《Physical review letters》2008,101(10):101101
This Letter reports the results of a search for a stochastic background of gravitational waves (GW) at 100 MHz by laser interferometry. We have developed a GW detector, which is a pair of 75-cm baseline synchronous recycling (resonant recycling) interferometers. Each interferometer has a strain sensitivity of approximately 10;{-16} Hz;{-1/2} at 100 MHz. By cross-correlating the outputs of the two interferometers within 1000 seconds, we found h{100};{2}Omega_{gw}<6 x 10;{25} to be an upper limit on the energy density spectrum of the GW background in a 2-kHz bandwidth around 100 MHz, where a flat spectrum is assumed. 相似文献
5.
Komarov V Azaryan T Chiladze D Dymov S Dzyuba A Hartmann M Kacharava A Keshelashvili I Khoukaz A Kulikov A Kurbatov V Macharashvili G Merzliakov S Mikirtychiants S Papenbrock M Nekipelov M Rathmann F Serdyuk V Ströher H Tsirkov D Uzikov Y Wilkin C 《Physical review letters》2008,101(10):102501
The fundamental reaction pp-->{pp}_{s}gamma, where {pp}_{s} is a proton pair with low excitation energy, has been observed with the ANKE spectrometer at COSY-Jülich for proton beam energies of T_{p}=0.353, 0.500, and 0.550 GeV. This is equivalent to photodisintegration of a free 1S0 diproton for photon energies E_{gamma} approximately T_{p}/2. The differential cross sections measured for c.m. angles 0 degrees gammad is on the 10;{-3}-10;{-2} level. The increase of the pp-->{pp}_{s}gamma cross section with T_{p} might reflect the influence of the Delta(1232) excitation. 相似文献
6.
《Physical review letters》2007,98(6):061802
Using 355 pb;{-1} of data collected by the CDF II detector in pp[over ] collisions at sqrt[s]=1.96 TeV at the Fermilab Tevatron, we study the fully reconstructed hadronic decays B_{(s)};{0}-->D_{(s)};{-}pi;{+} and B_{(s)};{0}-->D_{(s)};{-}pi;{+}pi;{+}pi;{-}. We present the first measurement of the ratio of branching fractions B(B_{s};{0}-->D_{s};{-}pi;{+}pi;{+}pi;{-})/B(B;{0}-->D;{-}pi;{+}pi;{+}pi;{-})=1.05+/-0.10(stat)+/-0.22(syst). We also update our measurement of B(B_{s};{0}-->D_{s};{-}pi;{+})/B(B;{0}-->D;{-}pi;{+}) to 1.13+/-0.08(stat)+/-0.23(syst), improving the statistical uncertainty by more than a factor of 2. We find B(B_{s};{0}-->D_{s};{-}pi;{+})=[3.8+/-0.3(stat)+/-1.3(syst)]x10;{-3} and B(B_{s};{0}-->D_{s};{-}pi;{+}pi;{+}pi;{-})=[8.4+/-0.8(stat)+/-3.2(syst)]x10;{-3}. 相似文献
7.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Garra Tico J Grauges E Lopez L Palano A Pappagallo M Eigen G Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lopes Pegna D Lynch G Mir LM Orimoto TJ Osipenkov IL Ronan MT Tackmann K Tanabe T Wenzel WA Del Amo Sanchez P Hawkes CM Watson AT Koch H Schroeder T Walker D Asgeirsson DJ Cuhadar-Donszelmann T Fulsom BG Hearty C 《Physical review letters》2008,100(17):171802
We present partial branching fractions for inclusive charmless semileptonic B decays B[over ]-->X_{u}lnu[over ], and the determination of the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}|. The analysis is based on a sample of 383 x 10;{6} Upsilon(4S) decays into BB[over ] pairs collected with the BABAR detector at the SLAC PEP-II e;{+}e;{-} storage rings. We select events using the invariant mass M_{X} of the hadronic system, the invariant mass squared, q;{2}, of the lepton and neutrino pair, the kinematic variable P+, or one of their combinations. We then determine partial branching fractions in limited regions of phase space: DeltaB=(1.18+/-0.09_{stat}+/-0.07_{syst}+/-0.01_{theor})x10;{-3} (M_{X}<1.55 GeV/c;{2}), DeltaB=(0.95+/-0.10_{stat}+/-0.08_{syst}+/-0.01_{theor})x10;{-3} (P+<0.66 GeV/c), and DeltaB=(0.81+/-0.08_{stat}+/-0.07_{syst}+/-0.02_{theor})x10;{-3} (M_{X}<1.7 GeV/c;{2}, q;{2}>8 GeV;{2}/c;{4}). Corresponding values of |V_{ub}| are extracted using several theoretical calculations. 相似文献
8.
Aubert B Barate R Bona M Boutigny D Couderc F Karyotakis Y Lees JP Poireau V Tisserand V Zghiche A Grauges E Lopez L Palano A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Charles E Gill MS Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Orimoto TJ Pripstein M Roe NA Ronan MT Wenzel WA Del Amo Sanchez P Barrett M Ford KE Harrison TJ Hart AJ Hawkes CM Morgan SE Watson AT Held T Koch H 《Physical review letters》2006,97(22):222001
We observe a new D_{s} meson with mass (2856.6+/-1.5_{stat}+/-5.0_{syst}) MeV/c;{2} and width (48+/-7_{stat}+/-10_{syst}) MeV/c;{2} decaying into D0K+ and D;{+}K_{S};{0}. In the same mass distributions, we also observe a broad structure with mass (2688+/-4_{stat}+/-3_{syst}) MeV/c;{2} and width (112+/-7_{stat}+/-36_{syst}) MeV/c;{2}. To obtain this result, we use 240 fb;{-1} of data recorded by the BABAR detector at the PEP-II asymmetric-energy e;{+}e;{-} storage rings at the Stanford Linear Accelerator Center running at center-of-mass energies near 10.6 GeV. 相似文献
9.
Delugas P Filippetti A Fiorentini V Bilc DI Fontaine D Ghosez P 《Physical review letters》2011,106(16):166807
We describe the intrinsic mechanism of 2-dimensional electron confinement at the n-type SrTiO3/LaAlO3 interface as a function of the sheet carrier density n(s) via advanced first-principles calculations. Electrons localize spontaneously in Ti 3d(xy) levels within a thin (?2 nm) interface-adjacent SrTiO3 region for n(s) lower than a threshold value n(c)~10(14) cm(-2). For n(s)>n(c) a portion of charge flows into Ti 3d(xz)-d(yz) levels extending farther from the interface. This intrinsic confinement can be attributed to the interface-induced symmetry breaking and localized nature of Ti 3d t(2g) states. The sheet carrier density directly controls the binding energy and the spatial extension of the conductive region. A direct, quantitative relation of these quantities with n(s) is provided. 相似文献
10.
Broun DM Huttema WA Turner PJ Ozcan S Morgan B Liang R Hardy WN Bonn DA 《Physical review letters》2007,99(23):237003
The superfluid density rho_{s}(T) identical with1/lambda;{2}(T) has been measured at 2.64 GHz in highly underdoped YBa_{2}Cu_{3}O_{6+y}, at 37 dopings with T_{c} between 3 and 17 K. Within limits set by the transition width DeltaT_{c} approximately 0.4 K, rho_{s}(T) shows no evidence of critical fluctuations as T-->T_{c}, with a mean-field-like transition and no indication of vortex unbinding. Instead, we propose that rho_{s} displays the behavior expected for a quantum phase transition in the (3+1)-dimensional XY universality class, with rho_{s0} proportional, variant(p-p_{c}), T_{c} proportional, variant(p-p_{c});{1/2}, and rho_{s}(T) proportional, variant(T_{c}-T);{1} as T-->T_{c}. 相似文献
11.
The conditions during light emission from the fracture of solids have been difficult to determine because such mechanoluminescence (ML) is usually weak. When ML is produced by acoustic cavitation of a liquid slurry of resorcinol crystals, however, we observe bright light emission, which makes it possible to measure plasma conditions by emission spectra: a bimodal heavy atom emission temperature profile is observed with 405+/-22 K (for 80% of emitting CH) and 4015+/-730 K (for 20%), with an electron density and energy of 1.3+/-0.13x10;{14} cm;{-3} and approximately 3.5 eV (i.e., an effective T_{e} approximately 41 000 K). 相似文献
12.
Dobbs S Metreveli Z Seth KK Tomaradze A Libby J Powell A Wilkinson G Ecklund KM Love W Savinov V Lopez A Mendez H Ramirez J Ge JY Miller DH Shipsey IP Xin B Adams GS Anderson M Cummings JP Danko I Hu D Moziak B Napolitano J He Q Insler J Muramatsu H Park CS Thorndike EH Yang F Artuso M Blusk S Khalil S Li J Mountain R Nisar S Randrianarivony K Sultana N Skwarnicki T Stone S Wang JC Zhang LM Bonvicini G Cinabro D Dubrovin M Lincoln A Naik P Rademacker J Asner DM Edwards KW Reed J Briere RA 《Physical review letters》2008,101(18):182003
A precision measurement of the mass of the h_{c}(1P1) state of charmonium has been made using a sample of 24.5x10;{6} psi(2S) events produced in e;{+}e;{-} annihilation at the Cornell Electron Storage Ring (CESR). The reaction used was psi(2S)-->pi;{0}h_{c}, pi;{0}-->gammagamma, h_{c}-->gammaeta_{c}, and the reaction products were detected in the CLEO-c detector. Data have been analyzed both for the inclusive reaction and for the exclusive reactions in which eta_{c} decays are reconstructed in 15 hadronic decay channels. Consistent results are obtained in the two analyses. The averaged results of the present measurements are M(h_{c})=3525.28+/-0.19(stat.)+/-0.12(syst.) MeV, and B(psi(2S)-->pi;{0}h_{c})xB(h_{c}-->gammaeta_{c})=(4.19+/-0.32+/-0.45)x10;{-4}. Using the ;{3}P_{J} centroid mass, DeltaM_{hf}(1P) identical withM(chi_{cJ})-M(h_{c})=+0.02+/-0.19+/-0.13 MeV. 相似文献
13.
Zizak I Darowski N Klaumünzer S Schumacher G Gerlach JW Assmann W 《Physical review letters》2008,101(6):065503
Vapor-deposited nanocrystalline titanium layers have been irradiated at room temperature with 350-MeV-Au ions up to 4x10;{15} Au/cm;{2}. Bombardment-induced texture changes were determined at the BESSY synchrotron light source. During off-normal irradiation, the nanocrystals undergo grain alignment and rotation up to approximately 90 degrees at the highest ion fluence. At the same time, the whole layer exhibits shear flow very similar to that observed previously in amorphous materials. Below 1x10;{15} Au/cm;{2}, a reversal of the ion incidence angle leads to a back rotation of the grains. These effects are absent or immeasurably small in coarse-grained titanium but have also been found in nanocrystalline TiN and NiO. The observations can be modeled by assuming that grain boundaries behave during ion bombardment like amorphous matter or by assuming a generation of disclination dipoles moving along grain boundaries. 相似文献
14.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Garra Tico J Grauges E Lopez L Palano A Eigen G Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lopes Pegna D Lynch G Mir LM Orimoto TJ Ronan MT Tackmann K Wenzel WA Del Amo Sanchez P Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M Schroeder T Steinke M Walker D Asgeirsson DJ Cuhadar-Donszelmann T Fulsom BG 《Physical review letters》2008,100(17):171803
We report on our search for decays proceeding via a tree-level b-->c quark transition in which a gluon radiates into an ss[over ] pair. We present observations of the decays B;{-}-->D_{s};{+}K;{-}pi;{-} and B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and evidence for B;{-}-->D_{s};{+}K;{-}K;{-} and set upper limits on the branching fractions for B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and B;{-}-->D_{s};{+}K;{-}K;{-} using 383x10;{6} Upsilon(4S)-->BB[over ] events collected by the BABAR detector at SLAC. We present evidence that the invariant mass distributions of D_{s};{+}K;{-} pairs from B;{-}-->D_{s};{+}K;{-}pi;{-} decays are inconsistent with the phase-space model, suggesting the presence of charm resonances lying below the D_{s};{+}K;{-} threshold. 相似文献
15.
Aubert B Bona M Karyotakis Y Lees JP Poireau V Prencipe E Prudent X Tisserand V Garra Tico J Grauges E Lopez L Palano A Pappagallo M Eigen G Stugu B Sun L Abrams GS Battaglia M Brown DN Cahn RN Jacobsen RG Kerth LT Kolomensky YG Kukartsev G Lynch G Osipenkov IL Ronan MT Tackmann K Tanabe T Hawkes CM Soni N Watson AT Koch H Schroeder T Walker D Asgeirsson DJ Cuhadar-Donszelmann T Fulsom BG Hearty C Mattison TS McKenna JA Barrett M Khan A Teodorescu L Blinov VE Bukin AD Buzykaev AR Druzhinin VP 《Physical review letters》2008,101(8):081801
We report measurements of branching fractions for the decays B-->Plnu_{l}, where P are the pseudoscalar charmless mesons pi;{-}, pi;{0}, eta and eta;{'}, based on 348 fb;{-1} of data collected with the BABAR detector, using B0 and B+ mesons found in the recoil of a second B meson decaying as B-->D;{(*)}lnu_{l}. Assuming isospin symmetry, we combine pionic branching fractions to obtain B(B;{0}-->pi;{-}l;{+}nu_{l})=(1.54+/-0.17_{(stat)}+/-0.09_{(syst)})x10;{-4}; we find 3.2sigma evidence of the decay B;{+}-->etal;{+}nu_{l} and measure its branching fraction to be (0.64+/-0.20_{(stat)}+/-0.03_{(syst)})x10;{-4}, and determine B(B;{+}-->eta;{'}l;{+}nu_{l})<0.47x10;{-4} to 90% confidence level. Using partial branching fractions for the pionic decays in ranges of the momentum transfer and a variety of form factor calculation, we obtain values of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}| in ranging from 3.6x10;{-3} to 4.1x10;{-3}. 相似文献
16.
H. W. Grießhammer M. R. Schindler R. P. Springer 《The European Physical Journal A - Hadrons and Nuclei》2012,48(1):7
We calculate the (parity-violating) spin-rotation angle of a polarized neutron beam through hydrogen and deuterium targets,
using pionless effective field theory up to next-to-leading order. Our result is part of a program to obtain the five leading
independent low-energy parameters that characterize hadronic parity violation from few-body observables in one systematic
and consistent framework. The two spin-rotation angles provide independent constraints on these parameters. Our result for
np spin rotation is $\frac{1}
{\rho }\frac{{d\varphi _{PV}^{np} }}
{{dl}} = \left[ {4.5 \pm 0.5} \right] rad MeV^{ - \frac{1}
{2}} \left( {2g^{\left( {^3 S_1 - ^3 P_1 } \right)} + g^{\left( {^3 S_1 - ^3 P_1 } \right)} } \right) - \left[ {18.5 \pm 1.9} \right] rad MeV^{ - \frac{1}
{2}} \left( {g_{\left( {\Delta {\rm I} = 0} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} - 2g_{\left( {\Delta {\rm I} = 2} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} } \right)$\frac{1}
{\rho }\frac{{d\varphi _{PV}^{np} }}
{{dl}} = \left[ {4.5 \pm 0.5} \right] rad MeV^{ - \frac{1}
{2}} \left( {2g^{\left( {^3 S_1 - ^3 P_1 } \right)} + g^{\left( {^3 S_1 - ^3 P_1 } \right)} } \right) - \left[ {18.5 \pm 1.9} \right] rad MeV^{ - \frac{1}
{2}} \left( {g_{\left( {\Delta {\rm I} = 0} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} - 2g_{\left( {\Delta {\rm I} = 2} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} } \right), while for nd spin rotation we obtain $\frac{1}
{\rho }\frac{{d\varphi _{PV}^{nd} }}
{{dl}} = \left[ {8.0 \pm 0.8} \right] rad MeV^{ - \frac{1}
{2}} g^{\left( {^3 S_1 - ^1 P_1 } \right)} + \left[ {17.0 \pm 1.7} \right] rad MeV^{ - \frac{1}
{2}} g^{\left( {^3 S_1 - ^3 P_1 } \right)} + \left[ {2.3 \pm 0.5} \right] rad MeV^{ - \frac{1}
{2}} \left( {3g_{\left( {\Delta {\rm I} = 0} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} - 2g_{\left( {\Delta {\rm I} = 1} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} } \right)$\frac{1}
{\rho }\frac{{d\varphi _{PV}^{nd} }}
{{dl}} = \left[ {8.0 \pm 0.8} \right] rad MeV^{ - \frac{1}
{2}} g^{\left( {^3 S_1 - ^1 P_1 } \right)} + \left[ {17.0 \pm 1.7} \right] rad MeV^{ - \frac{1}
{2}} g^{\left( {^3 S_1 - ^3 P_1 } \right)} + \left[ {2.3 \pm 0.5} \right] rad MeV^{ - \frac{1}
{2}} \left( {3g_{\left( {\Delta {\rm I} = 0} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} - 2g_{\left( {\Delta {\rm I} = 1} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} } \right), where the g
(X-Y), in units of $MeV^{ - \frac{3}
{2}}$MeV^{ - \frac{3}
{2}}, are the presently unknown parameters in the leading-order parity-violating Lagrangian. Using naıve dimensional analysis
to estimate the typical size of the couplings, we expect the signal for standard target densities to be $\left| {\frac{{d\varphi _{PV} }}
{{dl}}} \right| \approx \left[ {10^{ - 7} \ldots 10^{ - 6} } \right]\frac{{rad}}
{m}$\left| {\frac{{d\varphi _{PV} }}
{{dl}}} \right| \approx \left[ {10^{ - 7} \ldots 10^{ - 6} } \right]\frac{{rad}}
{m} for both hydrogen and deuterium targets. We find no indication that the nd observable is enhanced compared to the np one. All results are properly renormalized. An estimate of the numerical and systematic uncertainties of our calculations
indicates excellent convergence. An appendix contains the relevant partial-wave projectors of the three-nucleon system. 相似文献
17.
Adams GS Anderson M Cummings JP Danko I Hu D Moziak B Napolitano J He Q Insler J Muramatsu H Park CS Thorndike EH Yang F Artuso M Blusk S Khalil S Li J Mountain R Nisar S Randrianarivony K Sultana N Skwarnicki T Stone S Wang JC Zhang LM Bonvicini G Cinabro D Dubrovin M Lincoln A Naik P Rademacker J Asner DM Edwards KW Reed J Briere RA Ferguson T Ma JS Tatishvili G Vogel H Watkins ME Rosner JL Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Galik RS Gibbons L Gray R Gray SW Hartill DL 《Physical review letters》2008,101(10):101801
We report the first observation of the decay J/psi-->3gamma. The signal has a statistical significance of 6sigma and corresponds to a branching fraction of B(J/psi-->3gamma)=(1.2+/-0.3+/-0.2)x10;{-5}, in which the errors are statistical and systematic, respectively. The measurement uses psi(2S)-->pi;{+}pi;{-}J/psi events acquired with the CLEO-c detector operating at the CESR e;{+}e;{-} collider. 相似文献
18.
Takizawa M Wadati H Tanaka K Hashimoto M Yoshida T Fujimori A Chikamatsu A Kumigashira H Oshima M Shibuya K Mihara T Ohnishi T Lippmaa M Kawasaki M Koinuma H Okamoto S Millis AJ 《Physical review letters》2006,97(5):057601
We have measured photoemission spectra of SrTiO3/LaTiO3 superlattices with a topmost SrTiO3 layer of variable thickness. A finite coherent spectral weight with a clear Fermi cutoff was observed at chemically abrupt SrTiO3/LaTiO3 interfaces, indicating that an "electronic reconstruction" occurs at the interface between the Mott insulator LaTiO3 and the band insulator SrTiO3. For SrTiO3/LaTiO3 interfaces annealed at high temperatures (approximately 1000 degrees C), which leads to Sr/La atomic interdiffusion and hence to the formation of La(1-x)Sr(x)TiO3-like material, the intensity of the incoherent part was found to be dramatically reduced whereas the coherent part with a sharp Fermi cutoff was enhanced due to the spread of charge. These important experimental features are well reproduced by layer dynamical-mean-field-theory calculation. 相似文献
19.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Garra Tico J Grauges E Lopez L Palano A Eigen G Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lopes Pegna D Lynch G Mir LM Orimoto TJ Ronan MT Tackmann K Wenzel WA Del Amo Sanchez P Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M Schroeder T Steinke M Walker D Asgeirsson DJ Cuhadar-Donszelmann T Fulsom BG 《Physical review letters》2007,99(26):261801
We present measurements of the branching fractions for the decays B;{+/-}-->a_{1};{+/-}(1260)pi;{0} and B;{+/-}-->a_{1};{0}(1260)pi;{+/-} from a data sample of 232x10;{6} BB[over ] pairs produced in e;{+}e;{-} annihilation through the Upsilon(4S) resonance. We measure the branching fraction B(B;{+/-}-->a_{1};{+/-}(1260)pi;{0})xB(a_{1};{+/-}(1260)-->pi;{-}pi;{+}pi;{+/-})=(13.2+/-2.7+/-2.1)x10;{-6} with a significance of 4.2sigma, and the branching fraction B(B;{+/-}-->a_{1};{0}(1260)pi;{+/-})xB(a_{1};{0}(1260)-->pi;{-}pi;{+}pi;{0})=(20.4+/-4.7+/-3.4)x10;{-6} with a significance of 3.8sigma, where the first error quoted is statistical and the second is systematic. 相似文献
20.
Aaltonen T Adelman J Akimoto T Albrow MG González BA Amerio S Amidei D Anastassov A Annovi A Antos J Aoki M Apollinari G Apresyan A Arisawa T Artikov A Ashmanskas W Attal A Aurisano A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Beauchemin PH Bedeschi F Bednar P Behari S Bellettini G Bellinger J Belloni A Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Bizjak I Blair RE Blocker C Blumenfeld B 《Physical review letters》2008,100(12):121802
We measure the time dependence of the ratio of decay rates for the rare decay D{0}-->K{+}pi{-} to the Cabibbo-favored decay D{0}-->K{-}pi;{+}. A signal of 12.7x10;{3} D{0}-->K{+}pi{-} decays was obtained using the Collider Detector at Fermilab II detector at the Fermilab Tevatron with an integrated luminosity of 1.5 fb;{-1}. We measure the D0-D[over ]{0} mixing parameters (R_{D},y{'},x{'2}), and find that the data are inconsistent with the no-mixing hypothesis with a probability equivalent to 3.8 Gaussian standard deviations. 相似文献