相关论文: Nearest neighbor vector analysis of sdss dr5 galax…

The Nearest Neighbour Spacing (NNS) distribution can be computed for generalized symmetric 2x2 matrices having different variances in the diagonal and in the off-diagonal elements. Tuning the relative value of the variances we show that the…

We have selected a sample of 88 nearby (z<0.1) galaxy clusters from the SDSS-DR4 with redshift information for the cluster members. We have derived global properties for each cluster, such as their mean recessional velocity, velocity…

In hierarchical models of galaxy formation, stellar tidal streams are expected around most, if not all, galaxies. Although these features may provide useful diagnostics of the $\Lambda$CDM model, their observational properties remain poorly…

The number and distribution of dwarf satellite galaxies remain a critical test of cold dark matter-dominated structure formation on small scales. Until recently, observational information about galaxy formation on these scales has been…

We measure the angular clustering of galaxies from the Sloan Digital Sky Survey Data Release 7 in order to probe the spatial distribution of satellite galaxies within their dark matter halos. Specifically, we measure the angular correlation…

(Abridged) In this first paper of a series, we report the creation of large and well-defined database that combines extensive new measurements and a literature search of 3876 supernovae (SNe) and their 3679 host galaxies located in the sky…

We show that, observationally, the projected local density distribution in high-z clusters is shifted towards higher values compared to clusters at lower redshift. To search for the origin of this evolution, we analyze a sample of haloes…

We use the Minimal Spanning Tree to characterize the aggregation level of given sets of points. We test 3 distances based on the histogram of the MST edges to discriminate between the distributions. We calibrate the method by using…

Flux-limited and volume-limited galaxy samples are constructed from SDSS data releases DR4, DR6 and DR7 for statistical analysis. The two-point correlation functions $\xi(s)$, monopole of three-point correlation functions $\zeta_0$,…

We study out-of-distribution (OOD) prediction behavior of neural networks when they classify images from unseen classes or corrupted images. To probe the OOD behavior, we introduce a new measure, nearest category generalization (NCG), where…

Several recent observations using large datasets of galaxies showed non-random distribution of the spin directions of spiral galaxies, even when the galaxies are too far from each other to have gravitational interaction. Here, a dataset of…

In this work the correlations between spatial concentrations of active nuclei (NLS and BLS) and concentration of galaxies of full uniform sample were obtained. Methods, developed by the author in earlier paper were used. Galaxies of this…

We perform a galaxy-galaxy lensing study by correlating the shapes of $\sim$2.7 $\times$ 10$^5$ galaxies selected from the VLA FIRST radio survey with the positions of $\sim$38.5 million SDSS galaxies, $\sim$132000 BCGs and $\sim$78000 SDSS…

In this paper, we present a sample of cluster galaxies devoted to study the environmental influence on the star-formation activity. This sample of galaxies inhabits in clusters showing a rich variety in their characteristics and have been…

We use multi-band imagery data from the Sloan Digital Sky Survey (SDSS) to measure projected distances of 302 supernova type Ia (SNIa) from the centre of their host galaxies, normalized to the galaxy's brightness scale length, with a…

Gravitational wave (GW) observatories are discovering binary neutron star mergers (BNSMs), and in at least one event we were able to track it down in multiple wavelengths of light, which allowed us to identify the host galaxy. Using a…

We investigate the relationship between quasars and close companion galaxies using photometry and spectroscopy from the large data set of the SDSS DR16 survey. From the SDSS-QSO catalog of quasars, we selected objects with 0.1 < z < 0.35…

We perform a statistical study focused on void environments. We examine galaxy density profiles around voids in the SDSS, finding a correlation between void--centric distance to the shell of maximum density and void radius when a maximum in…

The distribution of satellite galaxies relative to isolated host galaxies in the Sloan Digital Sky Survey (SDSS) is investigated. Host-satellite systems are selected using three different methods, yielding samples of ~3300, ~1600, and \~950…

Type Ia Supernovae (SNe Ia) are a critical tool in measuring the accelerating expansion of the universe. Recent efforts to improve these standard candles have focused on incorporating the effects of dust on distance measurements with SNe…