相关论文: K-corona recording in the range < 1.4 Rsun

Solar radio U-bursts are generated by electron beams traveling along closed magnetic loops in the solar corona. Low-frequency ($<$ 100 MHz) U-bursts serve as powerful diagnostic tools for studying large-sized coronal loops that extend into…

Understanding many physical processes in the solar atmosphere requires determination of the magnetic field in each atmospheric layer. However, direct measurements of the magnetic field in the Sun's corona are difficult to obtain. Using…

We present a photometrically accurate restitution of the K and F coronae from white-light images obtained over 24 Years [1996--2019] by the Large-Angle Spectrometric COronagraph "LASCO-C2" onboard the Solar and Heliospheric Observatory…

Context. Coronal loops are the basic building blocks of the solar corona, which are related to the mass supply and heating of solar plasmas in the corona. However, their fundamental magnetic structures are still not well understood. Most…

The basis for the application of Thomson scattering to the analysis of coronagraph images has been laid decades ago.Even though the basic formulation is undebated, a discussion has grown in recent years about the spatial distribution of…

In this paper, after briefly reviewing the theory of vectorial vortices, we describe our technological approach to generating the necessary phase helix, and report results obtained with the first optical vectorial vortex coronagraph (OVVC)…

Over the last decade, the vector-apodizing phase plate (vAPP) coronagraph has been developed from concept to on-sky application in many high-contrast imaging systems on 8-m class telescopes. The vAPP is an geometric-phase patterned…

New Swift monitoring observations of the variable, radio-quiet quasar, PDS 456, are presented. A bright X-ray flare was captured in September 2018, the flux increasing by a factor of 4 and with a doubling time-scale of 2 days. From the…

The Astro2020 decadal survey recommended an infrared, optical, ultra-violet (IR/O/UV) telescope with a $\sim$6~m inscribed diameter and equipped with a coronagraph instrument to directly image exoEarths in the habitable zone of their host…

The driving and excitation mechanisms of decay-less kink oscillations in coronal loops remain under debate. We aim to quantify and provide simple observational constraints on the photospheric driving of oscillating coronal loops in a few…

We describe a coronagraphic optic for use with CONICA at the VLT that provides suppression of diffraction from 1.8 to 7 lambda/D at 4.05 microns, an optimal wavelength for direct imaging of cool extrasolar planets. The optic is designed to…

We present in this Letter the first coordinated radio occultation measurements and ultraviolet observations of the inner corona below 5.5 Rs, obtained during the Galileo solar conjunction in January 1997, to establish the origin of the slow…

Context. Solar activity is often accompanied by solar radio emission, consisting of numerous types of solar radio bursts. At low frequencies (<100 MHz) radio bursts with short durations of milliseconds, such as solar S-bursts, have been…

We present first results of a novel technique that provides, for the first time, constraints on the energy input flux at the coronal base ($r\sim\,1.025\,{\rm R}_\odot$) of the quiet-Sun at a global scale. By combining differential emission…

Angular broadening observations of compact radio sources provide a powerful method for probing the solar corona and solar wind. Such observations enable studies of the phase structure function, turbulence amplitude, intermediate-scale…

The analysis of quickly damped transverse oscillations of solar coronal loops using magneto-hydrodynamic seismology allow us to infer physical parameters that are difficult to measure otherwise. Under the assumption that such damped…

The content of coronal material in the quiet Sun is not constant as soft X-ray and high-temperature EUV line observations have shown. New material, probably heated and evaporated from the chromosphere is occasionally injected even in the…

As a core ground-based coronal observation facility in China's low-latitude high-altitude regions, the Lijiang Coronagraph leverages the natural advantages of Lijiang Astronomical Observation Station, including its 3200 m altitude and low…

We have shown in paper I of this series (arXiv:1706.03795) that interstellar communication to nearby (pc) stars is possible at data rates of bits per second per Watt between a 1 m sized probe and a large receiving telescope (E-ELT, 39 m),…

The cosmic far-infrared background is now well measured from 140 micron to 1 mm. Uncertainties remain at 100 micron (and even more at 60 micron). These are dominated by limitations of the zodiacal model. The nature of sources dominating the…