相关论文: Measurement of the solar system acceleration using…
We aim to evaluate the possibility of improving the ICRS realization starting from the ICRF2 catalogue by investigating the coordinate time series of radio sources observed by VLBI between 1979 and 2016. Sources with long observational…
The measurement of Doppler velocities in spectroscopic solar observations requires a reference for the local frame of rest. The rotational and radial velocities of the Earth and the rotation of the Sun introduce velocity offsets in the…
Observational data indicate that the Milky Way is a barred spiral galaxy. Computation facilities and availability of data from Galactic surveys stimulate the appearance of models of the Galactic structure. More efforts to build dynamical…
We report here on multi-frequency VLBA observations of three extragalactic sources within 1 degree of the Galactic Center. These sources have been used as astrometric reference sources for VLA and VLBA determinations of the proper motion of…
A determination is made of the radiation emitted by a linearly uniformly accelerated uncharged dipole transmitter. It is found that, first of all, the radiation rate is given by the familiar Larmor formula, but it is augmented by an amount…
The long-term monitoring and high photometric precision of the Kepler satellite will provide a unique opportunity to sound the stellar cycles of many solar-type stars using asteroseismology. This can be achieved by studying periodic changes…
We provide formulae for the calculation of precise Doppler velocities of sunlight, in both the case of direct observations of the Sun and in reflection from the surfaces of solar system objects such as the Moon or asteroids. We discuss the…
Stellar activity induced by active structures (eg, spots, faculae) is known to strongly impact the radial velocity time series. It then limits the detection of small planetary RV signals (eg, an Earth-mass planet in the habitable zone of a…
In this paper we propose, in a preliminary way, a new Earth-based laboratory experiment aimed to the detection of the gravitomagnetic field of the Earth. It consists of the measurement of the difference of the circular frequencies of two…
Starting from the observed distribution of galaxy clusters in redshift space we use a two--step procedure to recover their distances and peculiar velocities. After statistically correcting for the unobserved cluster distribution in the zone…
The frequency of maximum oscillation power measured in dwarfs and giants exhibiting solar-like pulsations provides a precise, and potentially accurate, inference of the stellar surface gravity. An extensive comparison for about 40…
A novel interferometric technique that uses the spectrum of the current fluctuations of a quadratic detector, a type of detector commonly used in Astronomy, has recently been introduced. It has major advantages with respect to classical…
The model of stochastic acceleration of particles by turbulence has been successful in explaining many observed features of solar flares. Here we demonstrate a new method to obtain the accelerated electron spectrum and important…
Large-scale plasma flows in the Sun's convection zone likely play a major role in solar dynamics on decadal timescales. In particular, quantifying meridional motions is a critical ingredient for understanding the solar cycle and the…
Active Galactic Nuclei (AGNs) observed with the technique of very long baseline interferometry (VLBI) are used as fiducial references on the sky to precisely measure the shape and orientation of the Earth. Their positions form a celestial…
Starting from a static spherically symmetric solution of the Einstein's field equations in the second approximation in the perfect fluid scheme, in the exterior of the source, the corresponding metrics depend on a dimensionless parameter…
We develop a general method to "self-calibrate" observations of galaxy clustering with respect to systematics associated with photometric calibration errors. We first point out the danger posed by the multiplicative effect of calibration…
A propagation model of galactic cosmic protons through the Heliosphere was implemented using a 2-D Monte Carlo approach to determine the differential intensities of protons during the solar cycle 23. The model includes the effects due to…
We present a vector formulation of an interferometric observation of a star, including the effects of the barycentric motion of the observatory, the proper motions of the star, and the reflex motions of the star due to orbiting planets. We…
The gravitational attraction of the Galactic centre leads to the centrifugal acceleration of the Solar system barycentre. It results in secular aberration drift which displaces the position of the distant radio sources. The effect should be…