Octet baryon masses in next-to-next-to-next-to-leading order covariant baryon chiral perturbation theory

We study the ground-state octet baryon masses and sigma terms using the covariant baryon chiral perturbation theory (ChPT) with the extended-on-mass-shell (EOMS) renormalization scheme up to next-to-next-to-next-to-leading order (N$^3$LO). By adjusting the available 19 low-energy constants (LECs), a reasonable fit of the $n_f=2+1$ lattice quantum chromodynamics (LQCD) results from the PACS-CS, LHPC, HSC, QCDSF-UKQCD and NPLQCD collaborations is achieved. Finite-volume corrections to the lattice data are calculated self-consistently. Our study shows that N$^3$LO BChPT describes better the light quark mass evolution of the lattice data than the NNLO BChPT does and the various lattice simulations seem to be consistent with each other. We also predict the pion and strangeness sigma terms of the octet baryons using the LECs determined in the fit of their masses. The predicted pion- and strangeness-nucleon sigma terms are $\sigma_{\pi N}=43(1)(6)$ MeV and $\sigma_{s N}=126(24)(54)$ MeV, respectively.Comment: 28 pages, 6 figures, minor revisions, typos corrected, version to appear in JHE

Sinteza, karakterizacija i sonokatalitička aktivnost filmova Co/N/Er3+ : Y3Al5O12/TiO2 za razgradnju organskih bojila

The sonocatalytic degradation of organic dyes (C.I. 50040, C.I. Reactive Red 1, C.I. Acid Orange 7) catalysed by Co/N/Er3+ : Y3Al5O12/TiO2 films was studied. For the preparation of Co/N/Er3+ : Y3Al5O12/TiO2 films, the sol-gel coating process was used. The phase composition, morphology, precursor at different temperatures and emitting light properties of the calcined powders were analysed by X-ray diffraction (XRD), absorption spectra and upconversion emission spectra. The X-ray diffraction of powder samples of Co/N/Er3+ : Y3Al5O12/TiO2 took on anatase mine peaks and upconversion luminous agent, respectively. Analysis of absorption spectra of amorphous Co/N/Er3+ : Y3Al5O12/TiO2 showed that doping N stretching vibration peak of water or hydroxyl adsorption, Co2+ ion had very strong absorption in 1.0–1.7 μm wavelength range, the transition luminescence of Er3+ ions was just on Co2+ ions absorption band. The emission spectrum indicated that Co/N/Er3+ : Y3Al5O12/TiO2 could launch green 500–560 nm and red 650–700 nm, 525, 550 and 660 nm peaks corresponding to 2H11/2, 4S3/2 → 4I15/2 and 4H9/2 → 4I15/2 transition of Er3+. Doping Co and N enhanced the upconversion luminescence and absorption effect. Sonocatalytic degradation effect of organic dyes loading Co/N/Er3+ : Y3Al5O12/TiO2 was better when ultrasonic intensity was equal to 15 W cm–2. The degradation ratios of aqueous solutions of these three kinds of organic dyes by ultrasonic irradiation were obviously lower than by ultrasonic irradiation together with Co/N/Er3+ : Y3Al5O12/TiO2 films in the same conditions. Degradation kinetics of organic dyes by ultrasonic irradiation and by ultrasonic irradiation cooperating with Co/N/Er3+ : Y3Al5O12/TiO2 films followed the first-order reaction.Proučavana je sonokatalitička razgradnja organskih bojila (C.I. 50040, C.I. Reactive Red 1, C.I. Acid Orange 7) kataliziranih filmovima Co/N/Er3+ : Y3Al5O12/TiO2. Za pripravu filmova Co/N/Er3+ : Y3Al5O12/TiO2 korišten je sol-gel proces premazivanja. Fazni sastav, morfologija, prekursor na različitim temperaturama i svojstva emitiranja svjetlosti kalciniranog praška analizirani su rendgenskom difrakcijom (XRD), apsorpcijskim spektrom i emisijskim spektrom uzlazne pretvorbe. Rendgenska analiza praškastih uzoraka Co/N/Er3+ : Y3Al5O12/TiO2 obuhvatila je svjetlosni agens uzlazne pretvorbe. Analiza apsorpcijskog spektra amorfnog Co/N/Er3+ : Y3Al5O12/TiO2 pokazala je da je dopiranjem N maksimuma vibracije istezanja vode ili hidroksilne apsorpcije, Co2+ ion imao vrlo jaku apsorpciju pri valnoj duljini od 1.0 – 1.7 μm, a tranzicijska luminiscencija Er3+ iona bila je samo na apsorpcijskoj vrpci Co2+ iona. Emisijski spektar pokazao je da Co/N/Er3+ : Y3Al5O12/TiO2 može emitirati zeleno 500 – 560 nm, crveno 650 – 700 nm te maksimume od 525, 550 i 660 nm koji odgovaraju prijelazima 2H11/2, 4S3/2 → 4I15/2 i 4H9/2 → 4I15/2 za Er3+. Dopirani Co i N pojačali su luminiscenciju uzlazne pretvorbe i apsorpcijski učinak. Učinak sonokatalitičke razgradnje organskih bojila s filmovima Co/N/Er3+ : Y3Al5O12/TiO2 bio je bolji kad je ultrazvučni intenzitet bio jednak 15 W cm−2. Razgradni omjeri vodenih otopina ovih triju vrsta organskih bojila ultrazvučnim ozračenjem bili su znatno niži od ultrazvučnog ozračenja zajedno s filmovima Co/N/Er3+ : Y3Al5O12/TiO2 pri istim uvjetima. Kinetika razgradnje organskih bojila ultrazvučnim ozračenjem i ultrazvučnim ozračenjem s filmovima Co/N/Er3+ : Y3Al5O12/TiO2 pratila je reakciju prvog reda