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This study investigates the clustering and bias of Luminous Red Galaxies (LRG) in the BOSS-LOWZ, -CMASS, -COMB, and eBOSS samples, using two types of simulated lightcones: (i) high-fidelity lightcones from Uchuu N -body simulation, employing SHAM technique to assign LRG to (sub)haloes, and (ii) 16 000 covariance lightcones from GLAM-Uchuu N -body simulations, including LRG using HOD data from Uchuu. Our results indicate that Uchuu and glam lightcones closely replicate BOSS/eBOSS data, reproducing correlation function and power spectrum across scales from redshifts 0.2 to 1.0, from 2 to |$150 \,h^{-1}\,\mathrm{Mpc}$| in configuration space, from 0.005 to |$0.7\, h\,\mathrm{Mpc}^{-1}$| in Fourier space, and across different LRG stellar masses. Furthermore, comparing with existing MD-Patchy and EZmock BOSS/eBOSS lightcones based on approximate methods, our GLAM-Uchuu lightcones provide more precise clustering estimates. We identify significant deviations from observations within |$20 \,h^{-1}\,\mathrm{Mpc}$| scales in MD-Patchy and EZmock , with our covariance matrices indicating that these methods underestimate errors by between 10 per cent and 60 per cent. Lastly, we explore the impact of cosmology on galaxy clustering. Our findings suggest that, given the current level of uncertainties in BOSS/eBOSS data, distinguishing models with and without massive neutrino effects on large-scale structure (LSS) is challenging. This paper highlights the Uchuu and GLAM-Uchuu simulations' robustness in verifying the accuracy of Planck cosmological parameters, providing a strong foundation for enhancing lightcone construction in future LSS surveys. We also demonstrate that generating thousands of galaxy lightcones is feasible using N -body simulations with adequate mass and force resolution. [ABSTRACT FROM AUTHOR]

Measurements of the luminosity function of active galactic nuclei (AGN) at high redshift (z ≳ 6) are expected to suffer from field-to-field variance, including cosmic and Poisson variances. Future surveys, such as those from the Euclid telescope and JWST, will also be affected by field variance. We use the Uchuu simulation, a state-of-the-art cosmological N -body simulation with 2.1 trillion particles in a volume of 25.7 Gpc3, combined with a semi-analytic galaxy and AGN formation model, to generate the Uchuu–ν2GC catalogue, publicly available, that allows us to investigate the field-to-field variance of the luminosity function of AGN. With this Uchuu–ν2GC model, we quantify the cosmic variance as a function of survey area, AGN luminosity, and redshift. In general, cosmic variance decreases with increasing survey area and decreasing redshift. We find that at z ∼ 6 − 7, the cosmic variance depends weakly on AGN luminosity. This is because the typical mass of dark matter haloes in which AGN reside does not significantly depend on luminosity. Due to the rarity of AGN, Poisson variance dominates the total field-to-field variance, especially for bright AGN. We also examine the effect of parameters related to galaxy formation physics on the field variance. We discuss uncertainties present in the estimation of the faint-end of the AGN luminosity function from recent observations, and extend this to make predictions for the expected number of AGN and their variance for upcoming observations with Euclid , JWST, and the Legacy Survey of Space and Time (LSST). [ABSTRACT FROM AUTHOR]

We present the public data release of the Uchuu-UM galaxy catalogues by applying the UniverseMachine algorithm to assign galaxies to the dark matter haloes in the Uchuu N -body cosmological simulation. It includes a variety of baryonic properties for all galaxies down to ∼5 × 108 M⊙ with haloes in a mass range of 1010 < M halo/M⊙ < 5 × 1015 up to redshift z = 10. Uchuu-UM includes more than 104 cluster-size haloes in a volume of 8(h −1Gpc)3, reproducing observed stellar mass functions across the redshift range of z = 0−7, galaxy quenched fractions, and clustering statistics at low redshifts. Compared to the previous largest UM catalogue, the Uchuu-UM catalogue includes significantly more massive galaxies hosted by large-mass dark matter haloes. Overall, the number density profile of galaxies in dark matter haloes follows the dark matter profile, with the profile becoming steeper around the splashback radius and flattening at larger radii. The number density profile of galaxies tends to be steeper for larger stellar masses and depends on the colour of galaxies, with red galaxies having steeper slopes at all radii than blue galaxies. The quenched fraction exhibits a strong dependence on the stellar mass and increases towards the inner regions of clusters. The publicly available Uchuu-UM galaxy catalogue presented here can serve to model ongoing and upcoming large galaxy surveys. [ABSTRACT FROM AUTHOR]

In this work, we investigate the structural properties, distribution and abundance of ΛCDM dark matter subhaloes using the Phi-4096 and Uchuu suite of N-body cosmological simulations. Thanks to the combination of their large volume, high mass resolution and superb statistics, we are able to quantify – for the first time consistently over more than seven decades in ratio of subhalo-to-host-halo mass – dependencies of subhalo properties on mass, maximum circular velocity, V max, host halo mass, and distance to host halo centre. We also dissect the evolution of these dependencies over cosmic time. We provide accurate fits for the subhalo mass and velocity functions, both exhibiting decreasing power-law slopes and with no significant dependence on redshift. We also find subhalo abundance to depend weakly on host halo mass. Subhalo structural properties are codified via a concentration parameter, c V, that does not depend on any pre-defined density profile and relies only on V max. We derive the c V− V max relation and find an important dependence on distance of the subhalo to the host halo centre. Interestingly, we also find subhaloes of the same mass to be significantly more concentrated when they reside inside more massive hosts. Finally, we investigate the redshift evolution of c V, and provide accurate fits. Our results offer an unprecedented detailed characterization of the subhalo population, consistent over a wide range of subhalo and host halo masses, as well as cosmic times. Thus, we expect our work to be particularly useful for any future research involving dark matter halo substructure. [ABSTRACT FROM AUTHOR]

The objective of this research was to determine the factors that affect the hygienic-sanitary quality of raw milk sold in the sock of the Bolívar canton parish. It was a diagnosis through sheets of observation on 23 farms and 30 places of sale of this parish. We assessed the level of microbial contamination of 30 samples taken from places of sale (1 5 samples in the municipal market) and 1 5 samples in stores using plate count by planting of aerobic mesophyll (NTE INEN 1529-5), Staphylococcus aureus (NTE INEN 1529-14), total coliforms (NTE INEN 1529-7) and Salmonella (NTE INEN 1529-15). Data processing was used for cluster analysis and descriptive statistics using Microsoft Excel 2010 and statistical software SPSS v.21. The found results were mishandling of raw milk, inadequate infrastructure in places of production and marketing, high counts of CFU/ml in the analyzed samples of raw milk with a value of 1.6 x 106 CFU/ml, which exceeds the established by the NTE INEN 9 (2012), which is 1.5 x 106 CFU/ml, on the other hand was designed and delivered educational 53, 23 good practices of milking taken from Codex Alimentarius and 30 good practices of established marketing by the NTE INEN 2687, for which it is concluded the lack of hygiene in people as in kitchenware and improper operation during milking, handling and marketing affecting the hygienic-sanitary quality of raw milk in Calce-ta-Bolivar -- Manabi, Ecuador. [ABSTRACT FROM AUTHOR]