583 research outputs found
Effects of the Fourth Generation on in Mixing
We investigate the mass differences in the mixing
with a new up-like quark in the
sequential fourth generation model. We give the basic formulae for in this model and obtain two kinds of numerical results of which is the function of . We find that one of our
results can satisfy the present experimental low bound of . We
also get the constraints of the fourth generation CKM factor
, which is the function of , from the
experimental measurements of . Thus,
provide a possible test of the fourth generation and give a signal of the new
physics.Comment: 13 pages, 5 figures. accepted by Europ. Phys. Jour.
Connection between closeness of classical orbits and the factorization of radial Schr\"{o}dinger equation
It was shown that the Runge-Lenz vector for a hydrogen atom is equivalent to
the raising and lowering operators derived from the factorization of radial
Schr\"{o}dinger equation. Similar situation exists for an isotropic harmonic
oscillator. It seems that there may exist intimate relation between the
closeness of classical orbits and the factorization of radial Schr\"{o}dinger
equation. Some discussion was made about the factorization of a 1D
Schr\"{o}dinger equation.Comment: 14 pages, no figure
The and decays with the fourth generation
If the fourth generation fermions exist, the new quarks could influence the
branching ratios of the decays of and . We
obtain two solutions of the fourth generation CKM factor
from the decay of . We use these
two solutions to calculate the new contributions of the fourth generation quark
to Wilson coefficients of the decay of . The branching ratio
and the forward-backward asymmetry of the decay of in the two
cases are calculated. Our results are quite different from that of SM in one
case, almost same in another case. If Nature chooses the formmer, the meson
decays could provide a possible test of the forth generation existence.Comment: 10 pages, 5 figure
[N′-(3-Ethoxy-2-oxidobenzylidene-κO 2)-4-methylbenzohydrazidato-κ2 O,N′](methanolato-κO)oxidovanadium(V)
The title oxidovanadium(V) complex, [V(C17H16N2O3)(CH3O)O], was obtained by the reaction of 3-ethoxy-2-hydroxybenzaldehyde, 4-methylbenzohydrazide and vanadyl sulfate in methanol. The VV atom is coordinated by the O,N,O′-tridentate Schiff base ligand, one methanolate O atom and one oxide O atom, forming a distorted VO4N square-pyramidal coordination geometry. The oxide O atom lies at the apex of the square pyramid and the N atom of the ligand and the methanolate O atom are trans. The dihedral angle between the benzene rings of the ligand is 1.8 (3)°
{1-[(3,5-Dimethyl-4H-1,2,4-triazol-4-yl)imino]ethyl}ferrocene
In the title compound, [Fe(C5H5)(C11H13N4)], the triazolyl and Cp ring form a dihedral angle of 76.6 (3)°. In the crystal structure, there are both intra- and intermolecular C—H⋯π interactions, forming a one-dimensional chain structure along [010]
Effects of Forage Sources on Rumen Fermentation Characteristics, Performance, and Microbial Protein Synthesis in Midlactation Cows
Eight multiparous Holstein cows (632±12 kg BW; 135±16 DIM) were used in a replicated 4×4 Latin square design to evaluate the effects of forage sources on rumen fermentation characteristics, performance, and microbial protein (MCP) synthesis. The forage portion of the diets contained alfalfa hay (AH), oat hay (OH), Leymus chinensis (LC), or rice straw (RS) as the primary source of fiber. Diets were isonitrogenous and isocaloric, and cows were fed four corn silages based total mixed rations with equivalent nonfiber carbohydrate (NFC) and forage neutral detergent fiber (NDF). Dry matter intake was not affected by the source of dietary forages, ranging from 18.83 to 19.20 kg/d, consequently, milk yield was similar among diets. Because of the numerical differences in milk fat and milk protein concentrations, 4% FCM and ECM yields were unchanged (p>0.05). Mean rumen pH, NH3-N content, and concentrations of volatile fatty acids in the rumen fluid were not affected by the treatments (p>0.05). Dietary treatments did not affect the total tract apparent digestibility of dry matter, organic matter, and crude protein (p>0.05); however, digestibility of NDF and acid detergent fiber in RS diet was higher compared with AH, OH, and LC diets (p<0.05). Total purine derivative excretion was higher in cows fed AH, OH, and LC diets compared with those fed RS diet (p<0.05), consequently, estimated MCP synthesis was 124.35 g/d higher in cows fed AH diet compared with those fed RS diet (p<0.05). The results indicated that cows fed AH, OH, LC, and RS diets with an equivalent forage NDF and NFC have no unfavourable effect on the ruminal fermentation and productive parameters
The Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST) Quasar Survey: Quasar Properties from Data Release Six to Nine
We report the fourth installment in the series of the Large Sky Area
Multi-Object Fiber Spectroscopic Telescope (LAMOST) Quasar Survey, which
includes quasars observed between September, 2017 and June, 2021. There are in
total 13,066 quasars reliably identified, of which 6,685 are newly discovered
that are not reported in the SDSS DR14 quasar catalog or Million Quasars
catalog. Because LAMOST does not provide accurate absolute flux calibration, we
re-calibrate the spectra with the SDSS/Pan-STARRS1 multi-band photometric data.
The emission line properties of H, H, Mg\,{\sc ii} and C\,{\sc
iv}, and the continuum luminosities are measured by fitting the re-calibrated
spectra. We also estimate the single-epoch virial black hole masses () using the derived emission line and continuum parameters. This is the
first time that the emission line and continuum fluxes were estimated based on
LAMOST re-calibrated quasar spectra. The catalog and spectra for these quasars
are available online. After the nine-year LAMOST quasar survey, there are in
total 56,175 identified quasars, of which 24,127 are newly discovered. The
LAMOST quasar survey not only discovers a great number of new quasars, but also
provides a database for investigating the spectral variability of the quasars
observed by both LAMOST and SDSS, and finding rare quasars including
changing-look quasars and broad absorption line quasars.Comment: arXiv admin note: text overlap with arXiv:1811.01570, Accepted by
ApJ
- …