Distribution of magnetic fields in the quiet-Sun internetwork areas has been affected by weak polarization (in particular Stokes Q and U) signals. To improve the signal-to-noise ratio (SNR) of the weak polarization signals, several approaches, including temporal integrations, have been proposed in the literature. In this study, we aim to investigate a proper temporal-integration time with which...

Two rival hypotheses have been proposed for the origin of the compact radio flux observed in radio-quiet quasars (RQQs). It has been suggested that the radio emission in these objects, typically some two or three orders of magnitude less powerful than in radio-loud quasars (RLQs), represents either emission from a circumnuclear starburst or is produced by radio jets with bulk kinetic powers ∼ 1...

Although radio-quiet quasars (RQQs) constitute > ∼ 90% of optically-identified quasar samples their radio properties are only poorly understood. In this paper we present the results of a multi-frequency VLA study of 27 low-redshift RQQs. We detect radio emission from 20 objects, half of which are unresolved (≤ 0.24). In cases where significant structure can be resolved, double, triple and linea...

The overall structure and the fine structure of the solar photosphere outside active regions are largely understood, except possibly the important roles of a turbulent near-surface dynamo at its bottom, internal gravity waves at its top and small-scale vorticity. Classical one-dimensional static radiation-escape modelling has been replaced by three-dimensional time-dependent magento-hydrodynami...

The current paradigm for radio-quiet AGNs is reviewed, taking into account new results from recent large-scale surveys carried out from the ground and from space. Topics include structure of the central engine, AGN demography, fueling/triggering processes, and connection between the supermassive black hole, host galaxy, circumnuclear starburst and AGN. Dependences on AGN power and lookback time...

The Coronal Diagnostic Spectrometer (CDS) onboard the SOHO satellite has been used to obtain movies of quiet Sun regions at disc centre. These movies were used to study brightness variations of solar features at three different temperatures sampled simultaneously in the chromospheric He I 584.3 Å (2·104 K), the transition region O V 629.7 Å (2.5·105 K) and coronal Mg IX 368.1 Å (106 K) lines. I...

Although eye pain is often accompanied by redness or injection, pain can also occur with a quiet eye. Pain in a quiet eye can be the first sign of a vision-threatening condition, a more benign ophthalmologic condition, or a nonophthalmologic condition. Acute narrow-angle glaucoma is an emergent vision-threatening condition that requires immediate treatment and referral to an ophthalmologist. Al...