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J. Trnka

Publications and source records attributed to J. Trnka.

4 recordsLinked to original sources

Snowmass Theory Frontier Report

This report summarizes the recent progress and promising future directions in theoretical high-energy physics (HEP) identified within the Theory Frontier of the 2021 Snowmass Process.

hep-ph

B.R.N.O. Contributions #39 Times of minima

This paper presents 1463 times of minima for 455 objects acquired by 46 members and cooperating observers of the Variable Star and Exoplanet Section of the Czech Astronomical Society (B.R.N.O. Observing project). Observations were carried out between October 2013 - September 2014. Some neglected southern eclipsing binaries and newly discovered stars by the observers of project B.R.N.O. are included in the list.

astro-ph.SR

Weinberg sum rules at NLO in 1/Nc

We study the relevance of different renormalization schemes in Resonance Chiral Theory. The SS-PP correlator is explicitly computed at the one-loop level. Demanding the operator product expansion behaviour at short distances produces a new set of constraints, as some logarithmic terms are absent at high energies. Likewise, the loops induce subleading corrections in 1/Nc to the leading-order constraints, the Weinberg sum rules. We find that the short-distance conditions from a minimally subtracted scheme generate large uncertainties which, alternatively, can be largely simplified in other schemes.

hep-ph

High energy constraints in the octet SS-PP correlator and resonance saturation at NLO in 1/Nc

We study the octet SS-PP correlator within resonance chiral theory up to the one-loop level, i.e., up to next-to-leading order in the 1/Nc expansion. We will require that our correlator follows the power behaviour prescribed by the operator product expansion at high euclidian momentum. Nevertheless, we will not make use of short-distance constraints from other observables. Likewise, the high-energy behaviour will be demanded for the whole correlator, not for individual absorptive channels. The amplitude is progressively improved by considering more and more complicated operators in the hadronic lagrangian. Matching the resonance chiral theory result with chiral perturbation theory at low energies produces the estimates L_8(mu)^{SU(3)} = (1.0+-0.4)10^-3 and C_{38}(mu)^{SU(3)} = (8+-5) 10^-6 for mu=770 MeV. The effect of alternative renormalization schemes is also discussed in the article.

hep-ph