scholarly journals Measurement of theD0→π−e+νedifferential decay branching fraction as a function ofq2and study of form factor parametrizations

2015 ◽  
Vol 91 (5) ◽  
Author(s):  
J. P. Lees ◽  
V. Poireau ◽  
V. Tisserand ◽  
E. Grauges ◽  
A. Palano ◽  
...  
2001 ◽  
Vol 16 (supp01b) ◽  
pp. 639-641
Author(s):  
◽  
Daniel Cronin-Hennessy

We determine the CKM matrix element, |Vcb|, by measuring the differential decay rate of B→D*+ℓν as a function of w=vB · vD*. We extrapolate the decay rate to the kinematic point, w=1, where the form factor, ℱ(w), is accurately predicted by theory. We find ℱ(1)|Vcb|=0.0424±0.0018( stat. )±0.0019( syst. ). Integration of the differential decay rate, dΓ/dw, yields the B→D*+ℓν branching fraction, ℬ(B→D*+ℓν)=(5.66±0.29±0.33)%. The data are derived from 3.3 million [Formula: see text] events collected by the CLEO detector at CESR.


2021 ◽  
Vol 81 (5) ◽  
Author(s):  
L. von Detten ◽  
F. Noël ◽  
C. Hanhart ◽  
M. Hoferichter ◽  
B. Kubis

AbstractPion–kaon ($$\pi K$$ π K ) pairs occur frequently as final states in heavy-particle decays. A consistent treatment of $$\pi K$$ π K scattering and production amplitudes over a wide energy range is therefore mandatory for multiple applications: in Standard Model tests; to describe crossed channels in the quest for exotic hadronic states; and for an improved spectroscopy of excited kaon resonances. In the elastic region, the phase shifts of $$\pi K$$ π K scattering in a given partial wave are related to the phases of the respective $$\pi K$$ π K form factors by Watson’s theorem. Going beyond that, we here construct a representation of the scalar $$\pi K$$ π K form factor that includes inelastic effects via resonance exchange, while fulfilling all constraints from $$\pi K$$ π K scattering and maintaining the correct analytic structure. As a first application, we consider the decay $${\tau \rightarrow K_S\pi \nu _\tau }$$ τ → K S π ν τ , in particular, we study to which extent the S-wave $$K_0^*(1430)$$ K 0 ∗ ( 1430 ) and the P-wave $$K^*(1410)$$ K ∗ ( 1410 ) resonances can be differentiated and provide an improved estimate of the CP asymmetry produced by a tensor operator. Finally, we extract the pole parameters of the $$K_0^*(1430)$$ K 0 ∗ ( 1430 ) and $$K_0^*(1950)$$ K 0 ∗ ( 1950 ) resonances via Padé approximants, $$\sqrt{s_{K_0^*(1430)}}=[1408(48)-i\, 180(48)]\,\text {MeV}$$ s K 0 ∗ ( 1430 ) = [ 1408 ( 48 ) - i 180 ( 48 ) ] MeV and $$\sqrt{s_{K_0^*(1950)}}=[1863(12)-i\,136(20)]\,\text {MeV}$$ s K 0 ∗ ( 1950 ) = [ 1863 ( 12 ) - i 136 ( 20 ) ] MeV , as well as the pole residues. A generalization of the method also allows us to formally define a branching fraction for $${\tau \rightarrow K_0^*(1430)\nu _\tau }$$ τ → K 0 ∗ ( 1430 ) ν τ in terms of the corresponding residue, leading to the upper limit $${\text {BR}(\tau \rightarrow K_0^*(1430)\nu _\tau )<1.6 \times 10^{-4}}$$ BR ( τ → K 0 ∗ ( 1430 ) ν τ ) < 1.6 × 10 - 4 .


2012 ◽  
Vol 86 (9) ◽  
Author(s):  
J. P. Lees ◽  
V. Poireau ◽  
V. Tisserand ◽  
J. Garra Tico ◽  
E. Grauges ◽  
...  

Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).


1982 ◽  
Vol 43 (C7) ◽  
pp. C7-273-C7-278 ◽  
Author(s):  
P. Burlet ◽  
J. X. Boucherle ◽  
J. Rossat-Mignod ◽  
J. W. Cable ◽  
W. C. Koehler ◽  
...  

1982 ◽  
Vol 43 (C7) ◽  
pp. C7-263-C7-271 ◽  
Author(s):  
J. X. Boucherle ◽  
D. Ravot ◽  
J. Schweizer
Keyword(s):  

1982 ◽  
Vol 43 (C7) ◽  
pp. C7-253-C7-256
Author(s):  
H. Fuess ◽  
R. Müller ◽  
D. Schwabe ◽  
F. Tasset

Author(s):  
Kendall Scott Wills ◽  
Omar Diaz de Leon ◽  
Kartik Ramanujachar ◽  
Charles P. Todd

Abstract In the current generations of devices the die and its package are closely integrated to achieve desired performance and form factor. As a result, localization of continuity failures to either the die or the package is a challenging step in failure analysis of such devices. Time Domain Reflectometry [1] (TDR) is used to localize continuity failures. However the accuracy of measurement with TDR is inadequate for effective localization of the failsite. Additionally, this technique does not provide direct 3-Dimenstional information about the location of the defect. Super-conducting Quantum Interference Device (SQUID) Microscope is useful in localizing shorts in packages [2]. SQUID microscope can localize defects to within 5um in the X and Y directions and 35um in the Z direction. This accuracy is valuable in precise localization of the failsite within the die, package or the interfacial region in flipchip assemblies.


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