Related papers: Solar-like oscillations in Procyon A

We studied chromospheric oscillations using Atacama Large millimeter and sub-millimeter Array (ALMA) time-series of interferometric observations of the quiet Sun obtained at 3 mm with a 2-s cadence and a spatial resolution of a few arcsec.…

Using Atacama Large Millimeter/submillimeter Array (ALMA) observations of the quiet Sun at 1.26 and 3 mm, we study spatially resolved oscillations and transient brightenings, i.e. small, weak events of energy release. Both phenomena may…

Compared to the Sun, the atmospheric structure and convective flow in Procyon A exhibit the following characteristics: (1) the highly superadiabatic transition layer (SAL) is located at much shallower optical depth; it is in a dynamically…

The nearby star Procyon is a visual binary containing the F5 IV-V subgiant Procyon A, orbited in a 40.84 yr period by the faint DQZ white dwarf Procyon B. Using images obtained over two decades with the Hubble Space Telescope, and…

We use high spatial and temporal resolution observations, simultaneously obtained with the New Vacuum Solar Telescope and Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory, to investigate the high-frequency…

We present a study of diffuse extragalactic radio emission at $1.75\,$GHz from part of the ELAIS-S1 field using the Australia Telescope Compact Array. The resulting mosaic is $2.46\,$deg$^2$, with a roughly constant noise region of…

Regular observations of active processes in the solar atmosphere have been started using the first stage of the multiwave Siberian Radioheliograph (SRH), a T-shaped 48-antenna array with a 4-8 GHz operating frequency range and a 10 MHz…

The preflare phase of the flare SOL2011-08-09T03:52 is unique in its long duration, its coverage by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Nobeyama Radioheliograph, and the presence of three well-developed…

We report the presence of a 106-day cycle in the radio variability of Sgr A* based on an analysis of data observed with the Very Large Array (VLA) over the past 20 years. The pulsed signal is most clearly seen at 1.3 cm with a ratio of…

Here we present a detailed analysis of solar acoustic mode frequencies and their rotational splittings for modes with degree up to 900. They were obtained by applying spherical harmonic decomposition to full-disk solar images observed by…

High-quality spectropolarimetry (range 417-860 nm; spectral resolution 1.27 nm and 0.265 nm/pixel) of the SN Ia 2001el were obtained with the ESO Very Large Telescope Melipal (+ FORS1) at 5 epochs. The spectra a week before maximum and…

We present the power spectrum of solar irradiance during 1985 and 1987 obtained from the ACRIM project from time scales of minutes to months. At low frequency the spectra are Lorentzian. At higher frequencies they are proportional to…

The amplitudes of solar-like oscillations depend on the excitation and damping, both of which are controlled by convection. Comparing observations with theory should therefore improve our understanding of the underlying physics. However,…

By direct measurements of the gas temperature, the Atacama Large Millimeter/sub-millimeter Array (ALMA) has yielded a new diagnostic tool to study the solar chromosphere. Here we present an overview of the brightness-temperature…

We present high sensitivity polarimetric observations in 6 bands covering the 5.5-38 GHz range of a complete sample of 53 compact extragalactic radio sources brighter than 200 mJy at 20 GHz. The observations, carried out with the Australia…

We report measurements of the fluctuations in atmospheric emission (atmospheric noise) above Mauna Kea recorded with Bolocam at 143 and 268 GHz from the Caltech Submillimeter Observatory (CSO). The 143 GHz data were collected during a 40…

We used long duration, high quality, unresolved (Sun-as-a star) observations collected by the ground based network BiSON and by the instruments GOLF and VIRGO on board the ESA/NASA SOHO satellite to search for solar-cycle-related changes in…

We observed a nearby radio galaxy, the Centaurus A (Cen A), three times with Suzaku in 2009, and measured the wide-band X-ray spectral variability more accurately than the previous measurements. The Cen A was in the active phase in 2009,…

As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216 sq. deg. of the southern sky at 18GHz (16mm) using a novel wide-band (3.4GHz bandwidth) analogue correlator on one baseline of the Australia…

Using high cadence observations from the Hydrogen-alpha Rapid Dynamics camera imaging system on the Dunn Solar Telescope, we present an investigation of the statistical properties of transverse oscillations in spicules captured above the…