Search Publications
Kinematics of OB-associations in Gaia epoch
Dambis, A. K.; Mel'nik, A. M.
We use stellar proper motions from the Tycho-Gaia Astrometric Solution (TGAS) catalogue to study the kinematics of OB-associations. The TGAS proper motions of OB-associations generally agree well with the Hipparcos proper motions. The parameters of the Galactic rotation curve obtained with TGAS and Hipparcos proper motions agree within the errors.…
The search for multiple populations in Magellanic Cloud clusters - I. Two stellar populations in the Small Magellanic Cloud globular cluster NGC 121
Dalessandro, E.; Salaris, M.; Larsen, S. +14 more
We started a photometric survey using the WFC3/UVIS instrument onboard the Hubble Space Telescope to search for multiple populations within Magellanic Cloud star clusters at various ages. In this paper, we introduce this survey. As first results of this programme, we also present multiband photometric observations of NGC 121 in different filters t…
On a New Theoretical Framework for RR Lyrae Stars. II. Mid-infrared Period-Luminosity-Metallicity Relations
Madore, Barry F.; Freedman, Wendy L.; Beaton, Rachael L. +14 more
We present new theoretical period-luminosity-metallicity (PLZ) relations for RR Lyræ stars (RRLs) at Spitzer and WISE wavelengths. The PLZ relations were derived using nonlinear, time-dependent convective hydrodynamical models for a broad range of metal abundances (Z = 0.0001-0.0198). In deriving the light curves, we tested two sets of atmospheric…
BICEP2 / Keck Array IX: New bounds on anisotropies of CMB polarization rotation and implications for axionlike particles and primordial magnetic fields
Ade, P. A. R.; Bock, J. J.; Crill, B. P. +64 more
We present the strongest constraints to date on anisotropies of cosmic microwave background (CMB) polarization rotation derived from 150 GHz data taken by the BICEP2 & Keck Array CMB experiments up to and including the 2014 observing season (BK14). The definition of the polarization angle in BK14 maps has gone through self-calibration in which…
A centrally heated dark halo for our Galaxy
Binney, James; Cole, D. R.
We construct a new family of models of our Galaxy in which dark matter and disc stars are both represented by distribution functions that are analytic functions of the action integrals of motion. The potential that is self-consistently generated by the dark matter, stars, and gas is determined, and parameters in the distribution functions are adju…
The black hole binary V404 Cygni: a highly accreting obscured AGN analogue
Motta, S. E.; Sánchez-Fernández, C.; Kuulkers, E. +2 more
Typical black hole binaries in outburst show spectral states and transitions, characterized by a clear connection between the inflow on to the black hole and outflows from its vicinity. The transient stellar mass black hole binary V404 Cyg apparently does not fit in this picture. Its outbursts are characterized by intense flares and intermittent p…
The SOFIA Massive (SOMA) Star Formation Survey. I. Overview and First Results
Tanaka, Kei E. I.; Zhang, Yichen; Tan, Jonathan C. +6 more
We present an overview and first results of the Stratospheric Observatory For Infrared Astronomy Massive (SOMA) Star Formation Survey, which is using the FORCAST instrument to image massive protostars from ∼10 to 40 µm. These wavelengths trace thermal emission from warm dust, which in Core Accretion models mainly emerges from the inner regio…
A test of Gaia Data Release 1 parallaxes: implications for the local distance scale
Casertano, Stefano; Riess, Adam G.; Bucciarelli, Beatrice +1 more
Aims: We present a comparison of Gaia Data Release 1 (DR1) parallaxes with photometric parallaxes for a sample of 212 Galactic Cepheids at a median distance of 2 kpc, and explore their implications on the distance scale and the local value of the Hubble constant H0.
Methods: The Cepheid distances are estimated from a recent ca…
The lensing and temperature imprints of voids on the cosmic microwave background
Cai, Yan-Chuan; Neyrinck, Mark; Mao, Qingqing +3 more
We have searched for the signature of cosmic voids in the cosmic microwave background (CMB), in both the Planck temperature and lensing-convergence maps; voids should give decrements in both. We use ZOBOV voids from the Data Release 12 Sloan Digital Sky Survey CMASS galaxy sample. We base our analysis on N-body simulations, to avoid a posteriori b…
Cosmological parameters, shear maps and power spectra from CFHTLenS using Bayesian hierarchical inference
Jaffe, Andrew H.; Heavens, Alan; Alsing, Justin
We apply two Bayesian hierarchical inference schemes to infer shear power spectra, shear maps and cosmological parameters from the Canada-France-Hawaii Telescope (CFHTLenS) weak lensing survey - the first application of this method to data. In the first approach, we sample the joint posterior distribution of the shear maps and power spectra by Gib…