相关论文: Constraining Ultra-light Axions with Galaxy Cluste…
Gravitational lensing has now become a popular tool to measure the mass distribution of structures in the Universe on various scales. Here we focus on the study of galaxy's scale dark matter halos with galaxy-galaxy lensing techniques:…
Adopting the framework of the Halo Occupation Distribution (HOD), we investigate the ability of galaxy clustering measurements to simultaneously constrain cosmological parameters and galaxy bias. Starting with a fiducial cosmological model…
In this work we show that combining different cluster data sets is a powerful tool to constrain both, the cosmology and cluster properties. We assume a model with 9 parameters and fit them to 5 cluster data sets. From that fit, we conclude…
Galaxy clusters trace the highest density peaks in the large-scale structure of the Universe. Their clustering provides a powerful probe that can be exploited in combination with cluster mass measurements to strengthen the cosmological…
We demonstrate that constraints on cosmological parameters from the distribution of clusters as a function of redshift (dN/dz) are complementary to accurate angular diameter distance (D_A) measurements to clusters, and their combination…
We study the angular clustering of Quaia, a Gaia- and unWISE-based catalog of over a million quasars with an exceptionally well-defined selection function. With it, we derive cosmology constraints from the amplitude and growth of structure…
Dark matter in the form of axions is expected to form miniclusters, and their dense regions can harbor compact axion stars. Such axion stars could be discovered by microlensing events. In particular, some candidate events reported by Subaru…
In this work we show how well can the cosmological parameters be constrained using galaxy cluster data. We also show how in the process of fitting the model which attempts to describe the data it is possible to get some information about…
Present and future large scale surveys offer promising probes of cosmology. For example the Dark Energy Survey (DES) is forecast to detect ~300 millions galaxies and thousands clusters up to redshift ~1.3. I here show ongoing work to…
Galaxy clusters, the pinnacle of structure formation in our universe, are a powerful cosmological probe. Several approaches have been proposed to express cluster number counts, but all these methods rely on empirical explicit scaling…
Clusters of galaxies are the most impressive gravitationally-bound systems in the Universe and its abundance (the cluster mass function) is one important statistics to probe the matter density parameter ($\Omega_m$) and the amplitude of…
The growth rate of large scale structure can probe whether dark matter clusters at gravitational strength or deviates from this, e.g. due to self interactions. Measurement of the growth rate through redshift space distortions in galaxy…
Future surveys of large-scale structure will be able to measure perturbations on the scale of the cosmological horizon, and so could potentially probe a number of novel relativistic effects that are negligibly small on sub-horizon scales.…
We show how observations of the evolution of the galaxy cluster number abundance can be used to constrain primordial non-Gaussianity in the universe. We carry out a maximum likelihood analysis incorporating a number of current datasets and…
This paper reviews the current status of measurements of galaxy clustering at high redshifts (z > 0.3). The focus is on the inherent limitations in the observation and interpretation of the ``evolution of clustering''. It is likely that…
New observational constraints on the cosmic matter density $\Omega_m$ and an effectively redshift-independent equation of state parameter $w_x$ of the dark energy are obtained while simultaneously testing the strong and null energy…
Compact stellar systems such as Ultra-compact dwarfs (UCDs) and Globular Clusters (GCs) around galaxies are known to be the tracers of the merger events that have been forming these galaxies. Therefore, identifying such systems allows to…
We study the formation of galaxy clusters in the presence of thawing class of scalar field dark energy. We consider cases where the scalar field has canonical as well non canonical kinetic term in its action. We also consider various form…
The cosmic microwave background (CMB) places strong constraints on models of dark matter (DM) that deviate from standard cold DM (CDM), and on initial conditions beyond the scalar adiabatic mode. Here, the full \textit{Planck} data set…
Sensitive, wide-area X-ray surveys which would be possible with the WFXT will detect huge samples of virialized objects spanning the mass range from sub-groups to the most massive clusters, and extending in redshift to beyond z=2. These…