Related papers: Measuring the Sun's Motion with Stellar Streams
We present a geometrodynamical method for determining distances to orbital streams of HI gas in the Galaxy. The method makes use of our offset from the Galactic centre and assumes that the gas comprising the stream nearly follows a planar…
We use cosmological hydrodynamical simulations of Milky-Way-mass galaxies from the FIRE project to evaluate various strategies for estimating the mass of a galaxy's stellar halo from deep, integrated-light images. We find good agreement…
We have measured the proper motion of the Draco dwarf galaxy using images at two epochs with a time baseline of about two years taken with the Hubble Space Telescope and the Advanced Camera for Surveys. Wide Field Channel 1 and 2 provide…
We review techniques for measuring stellar oscillations in solar-type stars. Despite great efforts, no unambiguous detections have been made. A new method, based on monitoring the equivalent widths of strong lines, shows promise but is yet…
Thin halo star streams originate from the evaporation of globular clusters and therefore provide information about the early epoch globular cluster population. The observed tidal tails from halo globular clusters in the Milky Way are much…
We have simulated the evolution of tidal debris in the Galactic halo in order to guide our ongoing survey to determine the fraction of halo mass accreted via satellite infall. Contrary to naive expectations that the satellite debris will…
The solar modulation effect of Galactic cosmic rays is a time-dependent phenomenon that is caused by the transport of these particles through the magnetized plasma of the heliosphere. Using a data-driven model of cosmic-ray transport in the…
Galaxy-galaxy lensing is a powerful probe of the relation between galaxies and dark matter halos, but its theoretical interpretation requires a careful modeling of various contributions, such as the contribution from central and satellite…
Solar analogs, broadly defined as stars similar to the Sun in mass or spectral type, provide a useful laboratory for exploring the range of Sun-like behaviors and exploring the physical mechanisms underlying some of the Sun's most elusive…
We illustrate a method for estimating the vertical position of the Sun above the Galactic plane by $\gamma$-ray observations. Photons of $\gamma$-ray wavelengths are particularly well suited for geometrical and kinematic studies of the…
One of the most promising tracers of the Galactic potential in the halo region are stellar streams. However, individual stream fits can be limited by systematic biases. To study these individual stream systematics, we fit streams in Milky…
In order to test the reliability of determinations of the shapes of galaxies' dark matter halos, we have made such measurements for the Milky Way by two independent methods, which make use of the stellar kinematics in the solar…
We develop a new method to measure source proper motions in microlensing events, which can partially overcome problems due to blending. It takes advantage of the fact that the source position is known precisely from the microlensing event…
We explore the phase-space structure of nearby halo stars identified kinematically from Gaia DR2 data. We focus on their distribution in velocity and in "integrals of motion" space as well as on their photometric properties. Our sample of…
The solar modulation effect of cosmic rays in the heliosphere is an energy-, time-, and particle-dependent phenomenon which arises from a combination of basic particle transport processes such as diffusion, convection, adiabatic cooling,…
A simple model for the Milky Way halo is presented. It has a flat rotation curve in the inner regions, but the density falls off sharply beyond an outer edge. This truncated, flat rotation curve (TF) model possesses a rich family of simple…
In determining the distances to stars within the Milky Way galaxy, one often uses photometric or spectroscopic parallax. In these methods, the type of each individual star is determined, and the absolute magnitude of that star type is…
Measurements of velocity and density perturbations along stellar streams in the Milky Way provide a time integrated measure of dark matter substructure at larger galactic radius than the complementary instantaneous inner halo strong lensing…
The Sun provides an excellent natural laboratory for nonlinear phenomena. We use motions of magnetic bright points on the solar surface, at the smallest scales yet observed, to study the small scale dynamics of the photospheric plasma. The…
We present a new approach for modelling galaxy/halo bias that utilizes the full non-linear information contained in the moments of the matter density field, which we derive using a set of numerical simulations. Although our method is…