3,866 research outputs found
Study of corrections for anomalous coupling limits due to the possible background BSM contributions
The search of the anomalous couplings is one of the possible ways to find any
deviation from the Standard Model. The effective field theory is used to
parameterize the anomalous couplings in the Lagrangian with the operators of
higher dimensions, constructed from the SM fields. In the classical way, the
limits on the Wilson coefficients of these operators are set based on beyond
the Standard Model contributions induced for signal process, whereas the ones
induced for background processes are assumed to be negligible. This article
provides a study of the corrections to the limits on Wilson coefficients by
accounting beyond the Standard Model contributions induced for background
processes. The studies of and
productions in collisions with TeV and conditions of the
ATLAS experiment at the LHC are used as example. Cases of collected during Run
II and expected from Run III integrated luminosities of 139 fb and 300
fb are considered. The expected 95% CL limits on coefficients
, , and
are obtained both in classical way and in the way,
where the corrections from background anomalous contributions are applied.
Corrected one-dimensional limits from and
productions are up to 9.1% and 4.4% (depending on
operator) tighter than the classical ones respectively. Corrected combined
limits are up to 3.0% (depending on operator) tighter than the classical ones.
Corrections to two-dimensional limits are also obtained, corrected contours are
more stringent, than the classical ones, and the maximal improvement is of
17.2%
The increase of ultrasound measurements accuracy with the use of two-frequency sounding
In the article the new method for detection of the temporary position of the received echo signal is considered. The method consists in successive emission of sounded impulses on two frequencies and also the current study is concerned with the analysis of ultrasound fluctuation propagation time to and from the deflector on every frequency. The detailed description of the mathematical tool is presented in the article. The math tool used allows the authors to decrease the measurement error with help of calculations needed
Spin-polarized electronic structure of the core-shell ZnO/ZnO:Mn nanowires probed by x-ray absorption and emission spectroscopy
The combination of x-ray spectroscopy methods complemented with theoretical
analysis unravels the coexistence of paramagnetic and antiferromagnetic phases
in the Zn_0.9Mn_0.1O shell deposited onto array of wurtzite ZnO nanowires. The
shell is crystalline with orientation toward the ZnO growth axis, as
demonstrated by X-ray linear dichroism. EXAFS analysis confirmed that more than
90% of Mn atoms substituted Zn in the shell while fraction of secondary phases
was below 10%. The value of manganese spin magnetic moment was estimated from
the Mn K{\beta} X-ray emission spectroscopy to be 4.3{\mu}B which is close to
the theoretical value for substitutional Mn_Zn. However the analysis of L_2,3
x-ray magnetic circular dichroism data showed paramagnetic behaviour with
saturated spin magnetic moment value of 1.95{\mu}B as determined directly from
the spin sum rule. After quantitative analysis employing atomic multiplet
simulations such difference was explained by a coexistence of paramagnetic
phase and local antiferromagnetic coupling of Mn magnetic moments. Finally,
spin-polarized electron density of states was probed by the spin-resolved Mn
K-edge XANES spectroscopy and consequently analyzed by band structure
calculations.Comment: Supplementary information available at
http://www.rsc.org/suppdata/ja/c3/c3ja50153a/c3ja50153a.pdf J. Anal. At.
Spectrom., 201
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