Publications (26)
A geometrical 1% distance to the short-period binary Cepheid V1334 Cygni
A. Gallenne, P. Kervella, N. R. Evans +18
Cepheid stars play a considerable role as extragalactic distances indicators, thanks to the simple empirical relation between their pulsation period and their luminosity. They over…
The 55 Cancri System: Fundamental Stellar Parameters, Habitable Zone Planet, and Super-Earth Diameter
K. von Braun, T. S. Boyajian, T. A. ten Brummelaar +13
The bright star 55 Cancri is known to host five planets, including a transiting super-Earth. We use the CHARA Array to directly determine the following of 55 Cnc's stellar astrophy…
CFC+: Improved dynamics and gravitational waveforms from relativistic core collapse simulations
P. Cerda-Duran, G. Faye, H. Dimmelmeier +4
Core collapse supernovae are a promising source of detectable gravitational waves. Most of the existing (multidimensional) numerical simulations of core collapse in general relativ…
Data management to support reproducible research
B. A. Wandell, A. Rokem, L. M. Perry +2
We describe the current state and future plans for a set of tools for scientific data management (SDM) designed to support scientific transparency and reproducible research. SDM ha…
Coalescing Neutron Stars -- a Step Towards Physical Models. I. Hydrodynamic Evolution and Gravitational-Wave Emission
M. Ruffert, H. -Th. Janka, G. Schaefer
We investigate the dynamics and evolution of coalescing neutron stars. Although the code (Piecewise Parabolic Method) is purely Newtonian, we do include the emission of gravitation…
A skeleton approximate solution of the Einstein field equations for multiple black-hole systems
G. Faye, P. Jaranowski, G. Schaefer
An approximate analytical and non-linear solution of the Einstein field equations is derived for a system of multiple non-rotating black holes. The associated space-time has the sa…
The Ages of A-Stars I: Interferometric Observations and Age Estimates for Stars in the Ursa Major Moving Group
Jeremy Jones, R. J. White, T. Boyajian +12
We have observed and spatially resolved a set of seven A-type stars in the nearby Ursa Major moving group with the Classic, CLIMB, and PAVO beam combiners on the CHARA Array. At le…
On the model of a classical relativistic particle of constant and universal mass and spin
V. Kassandrov, N. Markova, G. Schaefer +1
The deformation of the classical action for a free relativistic particle recently suggested by A. Staruszkiewicz gives rise to a spin structure which constrains the values of the i…
The binary black-hole dynamics at the third-and-a-half post-Newtonian order in the ADM-formalism
C. Koenigsdoerffer, G. Faye, G. Schaefer
We specialize the radiation-reaction part of the Arnowitt-Deser-Misner (ADM) Hamiltonian for many non-spinning point-like bodies, calculated by Jaranowski and Schaefer [1], to thir…
Toward Direct Detection of Hot Jupiters with Precision Closure Phase: Calibration Studies and First Results from the CHARA Array
M. Zhao, J. D. Monnier, X. Che +12
Direct detection of thermal emission from nearby hot Jupiters has greatly advanced our knowledge of extrasolar planets in recent years. Since hot Jupiter systems can be regarded as…
COALESCING NEUTRON STARS AS GAMMA RAY BURSTERS ?
M. Ruffert, H. -Th. Janka, W. Keil +1
We investigate the dynamics and evolution of coalescing neutron stars. The three-dimensional Newtonian equations of hydrodynamics are integrated by the `Piecewise Parabolic Method'…
Spectroscopy and Interferometry of Luminous Blue Variables
N. D. Richardson, D. R. Gies, N. D. Morrison +4
We report on the preliminary results of a three-year monitoring campaign of Galactic and Magellanic LBVs with both moderate and high resolution spectroscopy. We have collected more…
Gravitomagnetic Effects
G. Schaefer
The paper summarizes the most important effects in Einsteinian gravitomagnetic fields related to propagating light rays, moving clocks and atoms, orbiting objects, and precessing s…
HD 181068: A Red Giant in a Triply-Eclipsing Compact Hierarchical Triple System
A. Derekas, L. L. Kiss, T. Borkovits +41
Hierarchical triple systems comprise a close binary and a more distant component. They are important for testing theories of star formation and of stellar evolution in the presence…
The Age of the Directly-Imaged Planet Host Star Andromedae Determined From Interferometric Observations
Jeremy Jones, R. J. White, S. Quinn +4
Andromedae, an early type star that hosts a directly imaged low mass companion, is expected to be oblate due to its rapid rotational velocity ( = 162 $\mathrm{k…
Imaging the Algol Triple System in H Band with the CHARA Interferometer
F. Baron, J. D. Monnier, E. Pedretti +12
Algol (Beta Per) is an extensively studied hierarchical triple system whose inner pair is a prototype semi-detached binary with mass transfer occurring from the sub-giant secondary…
Gravimagnetic effect of the barycentric motion of the Sun and determination of the post-Newtonian parameter gamma in the Cassini experiment
S. M. Kopeikin, A. G. Polnarev, G. Schaefer +1
The most precise test of the post-Newtonian gamma parameter in the solar system has been achieved in measurement of the frequency shift of radio waves to and from the Cassini space…
Newborn Be star systems observed shortly after mass transfer
Th. Rivinius, R. Klement, S. D. Chojnowski +24
Many classical Be stars acquire their very rapid rotation by mass and angular-momentum transfer in massive binaries. Short-lived intermediate-phase objects have only been discovere…
A detailed analysis of the Gl 486 planetary system
J. A. Caballero, E. Gonzalez-Alvarez, M. Brady +64
The Gl 486 system consists of a very nearby, relatively bright, weakly active M3.5 V star at just 8 pc with a warm transiting rocky planet of about 1.3 R_Terra and 3.0 M_Terra that…
Recent Results form the CHARA Array
T. A. ten Brummelaar, D. Huber, K. von Braun +11
The CHARA Array is a six 1-m telescope optical and near infrared interferometer located at the Mount Wilson Observatory in southern California and operated by the Center for High A…
Coalescing neutron stars -- a step towards physical models. II. Neutrino emission, neutron tori, and gamma-ray bursts
M. Ruffert, H. -Th. Janka, K. Takahashi +1
Three-dimensional hydrodynamical, Newtonian calculations of the coalescence of equal-mass binary neutron stars are performed, including a physical high-density equation of state an…
Optical interferometry and Gaia measurement uncertainties reveal the physics of asymptotic giant branch stars
A. Chiavassa, K. Kravchenko, F. Millour +20
Context. Asymptotic giant branch stars are cool luminous evolved stars that are well observable across the Galaxy and populating Gaia data. They have complex stellar surface dynami…
The 2011 outburst of the recurrent novaT Pyx. Evidence for a face-on bipolar ejection
Olivier Chesneau, A. Meilland, D. P. K. Banerjee +19
We report on near-IR interferometric observations of the outburst of the recurrent nova T Pyx. We obtained near-IR observations of T Pyx at dates ranging from t=2.37d to t=48.2d af…
Spectral and spatial imaging of the Be+sdO binary phi Persei
D. Mourard, J. D. Monnier, A. Meilland +25
The rapidly rotating Be star phi Persei was spun up by mass and angular momentum transfer from a now stripped-down, hot subdwarf companion. Here we present the first high angular r…
Refined masses and distance of the young binary Haro 1-14 C
Jean-Baptiste Le Bouquin, J. -L. Monin, Jean-Philippe Berger +3
We aim to refine the dynamical masses of the individual component of the low-mass pre-main sequence binary Haro 1-14 C. We combine the data of the preliminary orbit presented previ…
Physical properties of beta Lyr A and its opaque accretion disk
D. Mourard, M. Broz, J. Nemravova +23
Mass exchange and mass loss in close binaries can significantly affect their evolution, but a complete self-consistent theory of these processes is still to be developed. Processes…