132 datasets found

Stellar flares are sudden brightenings caused by magnetic reconnection and are frequently observed on late-type stars. High-cadence photometry of flares provides valuable...

The EXTraS project, based on data collected with the XMM-Newton observatory, provided us with a vast amount of light curves for X-ray sources. For each light curve, EXTraS also...

The pulsar system PSR J1023+0038 is a very interesting binary with radio millisecond pulsar and low-mass X-ray binary transitions, which depend on the stellar accretion process....

We present time-series optical spectroscopy of two stellar flares with complex multi-peaked light curves: a 2.1_-.3_^+.4^x10^34^erg flare from an M8 ultra-cool dwarf, and a...

We present a Bayesian-odds-ratio-based algorithm for detecting stellar flares in light-curve data. We assume flares are described by a model in which there is a rapid rise with...

A combination of spectroscopic and photometric observations provides an excellent data sample for studying stellar chromospheric activity. We have combined LAMOST...

We have performed the first systematic search of the full Galaxy Evolution Explorer (GALEX) data archive for astrophysical variability on timescales of seconds to minutes by...

Stellar parameters and magnetic activity are important for the understanding of stellar physics and dynamo theory. We have used LAMOST spectroscopic surveys to study stellar...

Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) low- and medium-resolution spectroscopic surveys are important for determination of the orbital parameters and...

We present the first Fermi Large Area Telescope (LAT) catalog of long-term {gamma}-ray transient sources (1FLT). This comprises sources that were detected on monthly time...

The Lyman-alpha (Ly{alpha}) line of neutral hydrogen at 121.6nm is by far the brightest emission line in the vacuum ultraviolet spectral range of the Sun. The emission at this...

We present a homogeneous analysis of line and continuum emission from simultaneous high-cadence spectra and photometry covering near-ultraviolet and optical wavelengths for 20 M...

M-dwarfs are common stellar hosts of habitable-zone exoplanets. Near-UV (NUV) radiation can severely impact the atmospheric and surface conditions of such planets, making the...

We present light curves and flares from a 7 day, multiwavelength observational campaign of AU Mic, a young and active dM1e star with exoplanets and a debris disk. We report on...

The culmination of solar cycle 24 by the end of 2019 has created the opportunity to compare the differing properties of coronal mass ejections (CMEs) between two whole solar...

Solar-type stars exhibit their highest levels of magnetic activity during their early convective pre-main-sequence (PMS) phase of evolution. The most powerful PMS flares,...

Solar and stellar flares are powerful events that produce intense radiation across the electromagnetic spectrum. Multiwavelength observations are highly important for...

We report on a population of short-duration near-ultraviolet (NUV) flares in stars observed by the Kepler and Galaxy Evolution Explorer (GALEX) missions. We analyzed the NUV...

We search for superflares from 4068 cool stars in 2+yr of Evryscope photometry, focusing on those with high-cadence data from both Evryscope and the Transiting Exoplanet Survey...

One of the key problems in solar flare physics is the determination of the low-energy cut-off: the value that determines the energy of nonthermal electrons and hence flare...