Related papers: Unrecognized Astrometric Confusion in the Galactic…
The flux density from undetected sources in the observing beam of a telescope produces source confusion noise in the resulting maps of the sky, and thus limits sensitivity. In a recent paper we discussed this effect in the…
We report on the expected astrometric performance of the Thirty Meter Telescope's InfraRed Imaging Spectrometer (IRIS) as determined using simulated images of the Galactic center. This region of the Galaxy harbors a supermassive black hole…
Fluctuations in the brightness of the background radiation can lead to confusion with real point sources. Such background emission confusion will be important for infrared observations with relatively large beam sizes since the amount of…
We systematically investigate the error sources for high-precision astrometry from adaptive optics based near-infrared imaging data. We focus on the application in the crowded stellar field in the Galactic Center. We show that at the level…
Precision measurements of the stars in short-period orbits around the supermassive black hole at the Galactic Center are now being used to constrain general relativistic effects, such as the gravitational redshift and periapse precession.…
One of the greatest challenges facing gravitational wave astronomy in the low frequency band is the confusion noise generated by the vast numbers of unresolved galactic and extra galactic binary systems. Estimates of the binary confusion…
The effect of stars on the lensing properties of the supermassive black hole in the Galactic Center is similar to the effect of planets on microlensing by a star. We show that the dense stellar cluster around SgrA* increases by factors of a…
Because of their limited angular resolution, far-infrared telescopes are usually affected by confusion phenomenon. Since several galaxies can be located in the same instrumental beam, only the brightest objects emerge from the fluctuations…
At third-generation (3G) gravitational-wave detector networks, compact binaries coalescences produce a ``confusion noise'' due to unresolved sources and to the error in the reconstruction of resolved sources, that can degrade the…
In this paper we use the model of extragalactic background light to investigate the factors that have influence on the confusion noise. It was shown that (1) Large-Scale Structure of the Universe is an important factor; (2) gravitational…
Surface brightness asymmetries are a very common feature of stars. Among other effects they cause a difference between the projected barycentre and photocentre. The evolution of those surface features makes this difference time-dependent.…
In very crowded fields, the modulation of the background by the sea of unresolved faint sources induces centroid shifts. The errors increase with the number of sources per beam. Even the most optimistic simulations of imaging data show that…
The Galactic Centre black hole provides a naive environment for understanding unknown matter distribution and new gravitational physics. For this stellar orbits in the nuclear star cluster are reliable probes. We investigate different dark…
Giant arcs in strong lensing galaxy clusters can provide a purely geometric determination of cosmological parameters, such as the dark energy density and equation of state. We investigate sources of noise in cosmography with giant arcs,…
We present improved relative astrometry for stars within the central half parsec of our Galactic Center based on data obtained with the 10 m W. M. Keck Observatory from 1995 to 2017. The new methods used to improve the astrometric precision…
Upgrades beyond the current second generation of ground-based gravitational wave detectors will allow them to observe tens of thousands neutron star and black hole binaries. Given the typical minute-to-hour duration of neutron star signals…
Stars orbiting within 1$\arcsec$ of the supermassive black hole in the Galactic Centre, Sgr A*, are notoriously difficult to detect due to obscuration by gas and dust. We show that some stars orbiting this region may be detectable via…
The spin and quadrupole moment of the supermassive black hole at the Galactic center can in principle be measured via astrometric monitoring of stars orbiting at milliparsec (mpc) distances, allowing tests of general relativistic "no-hair"…
Astrometric monitoring of stars provides a promising method for discovery of low-mass planets around nearby Sun-like stars. The astronomical community has proposed several telescopes designed to perform high-precision astrometric…
An anomalous gamma-ray excess emission has been found in Fermi Large Area Telescope data covering the centre of the Galaxy. Several theories have been proposed for this `Galactic Centre Excess'. They include self-annihilation of dark matter…