Isospin-breaking effects on alpha extracted in B --> pi pi, rho rho, rho pi

Isospin-breaking in B --> pi pi caused by pi^0-eta-eta' mixing is studied in a model-independent way using flavor SU(3). Measured branching ratios for B^+ --> pi^+ pi^0, B^+ --> pi^+ eta^(') and B^0 --> pi^0 eta^(') imply an uncertainty in alpha smaller than 1.4 degree. We find a negligible effect of pi^0-eta-eta' mixing on alpha in B --> rho pi. Characterizing the effect of rho^0-omega mixing in B --> rho rho and in B --> rho pi by the two-pion invariant mass dependence, we point out a way of constraining this effect experimentally or eliminating it altogether. We show that a model-independent shift in alpha caused by electroweak penguin amplitudes in B --> pi pi and B --> rho rho, \Delta alpha_{EWP}=1.5+- 0.3 degree, may be slightly different in B --> rho pi. Other sources of isospin-breaking in these processes are briefly discussed.Comment: 21 pages, very slight changes, same version as in Physical Review

Semi-inclusive hadronic B decays as null tests of the Standard Model

We propose a new set of observables that can be used as experimental null tests of the Standard Model in charged and neutral B decays. The CP asymmetries in hadronic decays of charged B mesons into inclusive final states containing at least one of the following mesons: K_{S,L}, eta', c\bar c bound states or neutral K^* or D mesons, for all of which a U-spin rotation is equivalent to a CP conjugation, are CKM suppressed and furthermore vanish in the exact U-spin limit. We show how this reduces the theoretical error by using Soft Collinear Effective Theory to calculate the CP asymmetries for K_{S,L} X_{s+d}, K^* X_{s+d} and eta' X_{s+d} final states in the endpoint region. For these CP asymmetries only the flavor and not the charge of the decaying B meson needs to be tagged up to corrections of NLO in 1/m_b, making the measurements more accessible experimentally.Comment: 8 pages, significantly expanded after the observation that both neutral and charged B decays can be used, calculation for decays involving eta' adde

Electronic Structure of Hydrazinium (2 + ) Ion. A Semiempirical MO Treatment

A simple semiempjrical MO treatment of the electronic structure of hydrazinium (2 + ) ion was carried out on the basis of an extended Htickel method. The electronic population analysis for nitrogen and hydrogen atoms in this ion was calculated to b e (ls) 2 (2s)1 -121 (2px)1 ·3Go (2py)t·3Go (2p z)o .9BG and (ls)0o122, respectively

On measuring alpha in B(t)-> rho^\pm pi^\mp

Defining a most economical parametrization of time-dependent B-> rho^\pm pi^\mp decays, including a measurable phase alpha_{eff} which equals the weak phase alpha in the limit of vanishing penguin amplitudes, we propose two ways for determining alpha in this processes. We explain the limitation of one method, assuming only that two relevant tree amplitudes factorize and that their relative strong phase, delta_t, is negligible. The other method, based on broken flavor SU(3), permits a determination of alpha in B^0-> rho^\pm pi^\mp in an overconstrained system using also rate measurements of B^{0,+}-> K^* pi and B^{0,+}->rho K. Current data are shown to restrict two ratios of penguin and tree amplitudes, r_\pm, to a narrow range around 0.2, and to imply an upper bound |alpha_{eff} - alpha| < 15 degrees. Assuming that delta_t is much smaller than 90 degrees, we find alpha =(93\pm 16) degrees and (102 \pm 20) degrees using BABAR and BELLE results for B(t)-> rho^\pm pi^mp. Avoiding this assumption for completeness, we demonstrate the reduction of discrete ambiguities in alpha with increased statistics, and show that SU(3) breaking effects are effectively second order in r_\pm.Comment: 23 pages, 2 figures, data and references updated, to be published in Phys. Rev.

Bridge trisections and classical knotted surface theory

We seek to connect ideas in the theory of bridge trisections with other well-studied facets of classical knotted surface theory. First, we show how the normal Euler number can be computed from a tri-plane diagram, and we use this to give a trisection-theoretic proof of the Whitney-Massey Theorem, which bounds the possible values of this number in terms of the Euler characteristic. Second, we describe in detail how to compute the fundamental group and related invariants from a tri-plane diagram, and we use this, together with an analysis of bridge trisections of ribbon surfaces, to produce an infinite family of knotted spheres that admit non-isotopic bridge trisections of minimal complexity.Comment: v1 has been divided into two papers: the present article and "Bridge trisections and Seifert solids," which will be posted simultaneously; 29 pages, 11 figure

Some Slaughter and Carcass Traits of the Lambs of Dalmatian Pramenka Reared in Three Different Fattening Systems

In order to determine the impact of different fattening system (I - milk, pasture; II - indoors, milk, grains, III - milk, pasture, concentrate) on slaughter value and carcass quality of the lambs of Dalmatian Pramenka, 18 lambs (100 ± 5 days old), 6 in each group, were slaughtered. Lambs of one group were from the same flock and selected by birth weight (2.00 ± 0.20 kg). After slaughtering and cutting the carcasses into halves, in order to determine the share of legs and shoulders as well as certain tissues in the halves, the legs and shoulders were separated from the halves and total dissection was made. The significant differences (P<0.05) of slaughter weight (I - 21.17 kg, II - 23.25 kg, III - 26.25 kg) and hot carcass weight (I - 9.98 kg, II - 11.92 kg, III - 12.92 kg) among three groups were found. The legs II (1.65 kg) and III (1.71 kg) were significantly heavier (P<0.001) than legs I (1.32 kg), as well as shoulders (I - 0.52 kg, II - 0.65 kg, III - 0.69 kg; P<0.01). Total dissection of the halves established these tissues ratio: muscle 51.25 %, fat 10.18 %, connective 13.93%, bone 23.04% and other tissues 2.32%. The biggest quantity of muscle tissue was found in halves III (3.27 kg) what was more (P<0.05) than in halves II (2.83 kg) and I (2.50 kg). However, the biggest quantity of fat was found in halves II (0.85 kg) what was more (P<0.01) than in halves I (0.33 kg) and III (0.52 kg). Therefore, the addition of concentrate in pasture fattening system (III) increased the muscularity, without significantly increasing the amount of fat in the lamb carcass

Resting Behaviour of Broilers in Three Different Rearing Systems

The highest number of broilers is reared in the intensive fattening system on the floor with litter. Besides the intensive systems some sustainable rearing ways are also brought forward (ecological, biologic-dynamic, organic, etc.). The aim of this study was to establish the possible differences in resting behaviour of broilers in three rearing systems: intensive on the floor, free range, and organic system. The results showed great varieties between intensive and less intensive systems. In the intensive system on the floor animals rested statistically highly significantly more than in other two systems. However no differences in the behaviour of broilers in the stall were noticed, ifcompared to broilers in free range and those in the organic system. Comparison of the outdoor area showed that broilers rested statistically significantly more in the organic system. The reasons for different resting behaviour could be in leg weakness, body weight, group size, health problems, age, housing system, etc. Our research did not confirm our hypothesis that the older broilers rest more

Cohesive energies of cubic III-V semiconductors

Cohesive energies for twelve cubic III-V semiconductors with zincblende structure have been determined using an ab-initio scheme. Correlation contributions, in particular, have been evaluated using the coupled-cluster approach with single and double excitations (CCSD). This was done by means of increments obtained for localized bond orbitals and for pairs and triples of such bonds. Combining these results with corresponding Hartree-Fock data, we recover about 92 \% of the experimental cohesive energies.Comment: 16 pages, 1 figure, late