Related papers: Exploring Non-minimal coupling using ultra-diffuse…
Two ultra diffuse galaxies in the same group, NGC1052-DF2 and NGC1052-DF4, have been found to have little or no dark matter and to host unusually luminous globular cluster populations. Such low mass diffuse objects in a group environment…
We study CMB constraints on a model with a cosmological constant and a fraction of dark matter non-minimally coupled to a massless scalar field. In this scenario, there is an extra gravity-like fifth force which can affect the evolution of…
We present a non-parametric, model-independent reconstruction of the cosmological background and perturbation dynamics in non-minimally coupled theories of gravity. Within the Effective Field Theory of dark energy framework, we reconstruct…
We present new constraints on the density profiles of dark matter (DM) halos in seven nearby dwarf galaxies from measurements of their integrated stellar light and gas kinematics. The gas kinematics of low mass galaxies frequently suggest…
The dark matter content of galaxies is usually determined from galaxies in dynamical equilibrium, mainly from rotationally supported galactic components. Such determinations restrict measurements to special regions in galaxies, e.g. the…
We obtain very stringent bounds on the possible cold dark matter, baryon and neutrino isocurvature contributions to the primordial fluctuations in the Universe, using recent cosmic microwave background and large scale structure data. In…
It has been suggested that the internal dynamics of dwarf spheroidal galaxies (dSphs) can be used to test whether or not ultralight axions with $m_a\sim 10^{-22}\text{eV}$ are a preferred dark matter candidate. However, comparisons to…
The phenomenon of magnification bias can induce a non-negligible angular correlation between two samples of galaxies with nonoverlapping redshift distributions. This signal is particularly clear when background submillimeter galaxies are…
In this paper, we investigate the optical properties of a black hole in non-minimal Einstein-Yang-Mills theory, illuminated by a thin accretion disk. In our setup, matter follows stable circular orbits outside the innermost stable circular…
It is plausible that the dark matter particles have non-gravitational interactions among themselves. If such self interactions are large enough, they could leave an imprint on the morphology of galaxies. These effects can be studied with…
(Abridged) Present cosmological constraints and the absence of a direct detection and identification of any dark matter particle candidate leave room to the possibility that the dark sector of the Universe be actually more complex than it…
We study the internal response of a galaxy to an unbound encounter and present a survey of orbital parameters covering typical encounters in different galactic environments. Overall, we conclude that relatively weak encounters by low-mass…
Self-interacting dark matter may have striking astrophysical signatures, such as observable offsets between galaxies and dark matter in merging galaxy clusters. Numerical N-body simulations used to predict such observables typically treat…
We investigate the dynamics of eccentric binary pulsars embedded in dark matter environments. While previous studies have primarily focused on circular orbits in collisionless dark matter halos, we extend this framework to eccentric systems…
We investigate an extension of the $\Lambda$CDM model where the dark matter (DM) is coupled to photons, inducing a nonconservation of the numbers of particles for both species, where the DM particles are allowed to dilute throughout the…
The axion-like particles (ALPs) are very good candidates of the cosmological dark matter, which can exist in many extensions of the standard model (SM). The mass range of the ALPs as the dark matter can extend from a sub-eV scale to almost…
Subject of this paper are the statistical properties of ellipticity alignments between galaxies evoked by their coupled angular momenta. Starting from physical angular momentum models, we bridge the gap towards ellipticity correlations,…
A number of scenarios have been proposed to explain the low velocity dispersion (and hence possible absence of dark matter) of the low surface brightness galaxies NGC1052-DF2 and NGC1052-DF4. Most of the proposed mechanisms are based on the…
Until recently the study of the gravitational field of dark matter was primarily concerned with its local effects on the motion of stars in galaxies and galaxy clusters. On the other hand, the WMAP experiment has shown that the…
We investigate the dark matter density profile of the massive elliptical galaxy, NGC 1407, by constructing spherically symmetric Jeans models of its field star and globular cluster systems. Two major challenges in such models are the…