Search results for "systematic error"
showing 10 items of 52 documents
Orbit determination and errors of a star catalogue
1995
Abstract We obtain Ceres orbit taking into account all perturbations and applying correction of phase effect to observations. More than 3000 observations have been used and the results agree with other determinations. We have also investigated the influence of systematic errors of a star catalogue on the observations and its effect on final elements. To that aim, a simulation procedure has been applied to Ceres observations, including different laws for errors of star catalogue versus spherical coordinates. The best relations have been applied to real observations of Ceres, in order to obtain elements and star catalogue corrections. Preliminary results of these calculations are presented.
Emissivity errors in the vegetation cover method caused by the lack of atmospheric correction
2008
The influence of the lack of atmospheric correction of the optical images used to calculate land surface emissivity (LSE) was assessed. When thermal emissivity is determined by the vegetation cover method (VCM), information from the solar spectrum is required to calculate the vegetation cover fraction. The atmospheric correction was obtained in this study by using a combination of the dark dense vegetation (DDV) method and the Second Simulation of the Satellite Signal in the Solar Spectrum (6S) code. The methodology was applied to a Landsat Thematic Mapper (TM) image of Tomelloso, Spain. We determined that the emissivity between 10 and 12 µm only increases by 0.4% (which represents a system…
Measurements of Branching Fractions andCP-Violating Asymmetries inBMeson Decays to Charmless Two-Body States Containing aK0
2003
We present measurements of branching fractions and \CP-violating asymmetries in decays of $B$ mesons to two-body final states containing a \Kz. The results are based on a data sample of approximately 88 million \upsbb decays collected with the \babar detector at the \pep2 asymmetric-energy $B$ Factory at SLAC. We measure $\BR(\Bp\to\Kz\pip) = (22.3 \pm 1.7 \pm 1.1)\times 10^{-6}$, $\BR(\Bz\to\Kz\piz) = (11.4\pm 1.7\pm 0.8)\times 10^{-6}$, $\BR(\Bp\to\Kzb\Kp) < 2.5\times 10^{-6}$, and $\BR(\Bz\to\KzKzb) < 1.8\times 10^{-6}$, where the first uncertainty is statistical and the second is systematic, and the upper limits are at the 90% confidence level. In addition, the following \CP-violating a…
V-us determination from hyperon semileptonic decays
2005
16 páginas, 9 tablas.-- arXiv:hep-ph/0509045v2
Updated pseudoscalar contributions to the hadronic light-by-light of the muon (g-2)
2016
In this work, we present our recent results on a new and alternative data-driven determination for the hadronic light-by-light pseudoscalar-pole contribution to the muon $(g-2)$. Our approach is based on Canterbury approximants, a rational approach to describe the required transition form factors, which provides a systematic and model-independent framework beyond traditional large-$N_c$ approaches. As a result, we obtain a competitive determination with errors according to future $(g-2)$ experiments including, for the first time, a well-defined systematic uncertainty.
Improved measurement of the CKM angleγinB∓→D(*)K(*)∓decays with a Dalitz plot analysis ofDdecays toKS0π+π−andKS0K+K−
2008
We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub s}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub s}{sup 0}K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K8{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}. Using a sample of 383 million B{bar B} pairs collected by the BABAR detector, we measure {gamma} = (76 {+-} 22 {+-} 5{+-} 5){sup o} (mod 180{sup o}), where the first error is statistical, the second is the experimental systematic unc…
A test of chiral perturbation theory from the measurement of the decay KS → γγ
1995
Data from NA31 experiment at CERN have been used to measure the decay KS → γγ. From 69 candidate events of the type K0 → γγ, 52 events can be attributed to KL → γγ and one event is expected from background processes. The ratio of the relative decay widths R = Γ(KS → γγ)Γ(KL → γγ) is measured to be R = 2.2 ± 1.0(stat.) ± 0.3(syst.) ± 0.2(ext.) where the external systematic error is due to the experimental uncertainty in the branching ratio of the decay KL → γγ. This translates into a branching ratio of BR(KS → γγ) = (2.2 ± 1.1) × 10−6. If these data are combined with the published data from an earlier data taking period with the same experiment, the ratio R is determined to be R = 2.35 ± 0.7…
Search for promptly produced heavy quarkonium states in hadronic Z decays
1996
A search has been made for direct production of heavy quarkonium states in more than 3 million hadronic Z^{0} decays in the 1991-1994 DELPHI data. Prompt J/\psi, \psi(2S) and \Upsilon candidates have been searched for through their leptonic decay modes using criteria based on the kinematics and decay vertex positions. New upper limits are set at the 90 \% confidence level for {Br( Z^0 \rightarrow \left( Q \bar{Q} \right) X ) / Br( Z^0 \rightarrow \mbox{hadrons})} for various strong production mechanisms of J/\psi and \Upsilon; these range down to 0.9 \times 10^{-4}. The limits are set in the presence of a small excess (\sim 1 \% statistical probability of a background fluctuation) in the su…
Comparative study of several programs used in the potentiometric evaluation of equilibrium constants including an error sensitivity analysis
1989
Abstract The programs MINIQUAD, MINIPOT, SUPERQUAD and PHCONST are applied to the evaluation of the protonation constants of several hypothetical polyprotic substances using simulated titrations, and the precision and accuracy of the results are discussed and compared. When statistical weights are used the results are very similar, the accuracy being better with PHCONST. Error sensitivity analysis was used as a means of establishing the influence of a systematic error of an experimental variable on the accuracy of the determination. An algorithm for the accurate calculation of error sensitivities is proposed and checked. Error sensitivities can be used to make a choice between the various m…
Pion Form Factor Measurement and ISR at BESIII
2017
Abstract At BESIII, we measured the cross section of 900 MeV/c2 with a 2.93 fb−1 data set taken at the center-of-mass energy 3.773 GeV. The initial state radiation technique is used, and the total systematic uncertainty is estimated to be 0.9%. The squared form factor | F π | 2 is extracted, and comparisons are made with results from both KLOE and BaBar. The two-pion contribution to the hadronic vacuum polarization contribution to ( g − 2 ) μ is calculated to be a μ π π , LO ( 600 − 900 MeV / c 2 ) = ( 368.2 ± 2.5 s t a t . ± 3.3 s y s t . ) ⋅ 10 − 10 .