相关论文: Characterising fast-time variations in the hard X-…
Stellar dynamics indicate the presence of a super massive 3-4x10^6 Msun solm black hole at the Galactic Center. It is associated with the variable radio, near-infrared, and X-ray counterpart Sagittarius A* (SgrA*). The goal is the…
Context: Detailed oscillation spectra comprising individual frequencies for numerous solar-type stars and red giants are or will become available. These data can lead to a precise characterisation of stars. Aims: Our goal is to test and…
We present a case study of an M4-class flare on 28 March 2022, near Solar Orbiter's first science perihelion (0.33 AU). Solar Orbiter was 83.5{\deg} west of the Sun-Earth line, making the event appear near the eastern limb, while…
The study of massive star formation needs some basic tools, among which reliable SFR tracers are crucial ones. We are presently revising the calibration of SFR tracers at different wavelength ranges using last generation evolutionary…
INTEGRAL monitoring of the Galactic Plane in the last 5 years revealed a new subclass of High Mass X-ray Binaries (HMXBs), the Supergiant Fast X-ray Transients (SFXTs). They display flares lasting from minutes to hours, with peak luminosity…
This paper describes the development of X-ray diffractive optics for imaging solar flares with better than 0.1 arcsec angular resolution. X-ray images with this resolution of the \geq10 MK plasma in solar active regions and solar flares…
Electromagnetic radiation from blazar jets often displays strong variability, extending from radio to $\gamma$-ray frequencies. In a few cases, this variability has been characterized using Fourier time lags, such as those detected in the…
X-ray polarimetry of accreting compact objects has revealed fast time variations in the polarization angle (PA), suggesting that the geometry and/or optical depth of the Comptonization region is changing rapidly. This prompts investigations…
We present here the first systematic search of short timescale $\gamma$-ray flares from 29 high Galactic latitude BL Lac objects over 14 years of Fermi Large Area Telescope data. Using a combined Bayesian Blocks and HOP algorithm, we…
The pulsations of X-ray pulsars carry information about the accretion and magnetic field geometry. Here we present a study and classification of energy resolved pulse profiles of a sample of X-ray pulsars, focusing on high-mass X-ray…
Aima. To determine to what extent the problem of forward fitting visibilities measured by the Spectrometer/Telescope Imaging X-rays (STIX) on-board Solar Orbiter is more challenging with respect to the same problem in the case of previous…
Stellar flares are potent drivers of atmospheric evolution on orbiting exoplanets, primarily through extreme ultraviolet (EUV) and soft X-ray (XUV) irradiation. However, the contribution of hard X-rays (HXR; 3--20 keV)-which penetrate…
We compare multi-wavelength SFR indicators out to z~3 in GOODS-South. Our analysis uniquely combines U-to-8um photometry from FIREWORKS, MIPS 24um and PACS 70, 100, and 160um photometry from the PEP survey, and Ha spectroscopy from the SINS…
Much evidence suggests that the solar corona is heated impulsively, meaning that nanoflares may be ubiquitous in quiet and active regions (ARs). Hard X-ray (HXR) observations with unprecedented sensitivity $>$3~keV are now enabled by…
NICER has a comparatively low background rate, but it is highly variable, and its spectrum must be predicted using measurements unaffected by the science target. We describe an empirical, three-parameter model based on observations of seven…
Gamma-ray burst X-ray flares are believed to mark the late time activity of the central engine. We compute the temporal evolution of the average flare luminosity $< L >$ in the common rest frame energy band of 44 GRBs taken from the large…
Our work focuses on a comprehensive orbital phase dependent spectroscopy of the four High Mass X-ray Binary Pulsars (HMXBPs) 4U 1538-52, GX 301-2, OAO 1657-415 & Vela X-1. We hereby report the measurements of the variation of the absorption…
Radio observations from space allow to characterize solar radio bursts below the ionospheric cutoff, which are otherwise inaccessible, but suffer from low, insufficient temporal resolution. In this Letter we present novel, high-temporal…
High Mass X-ray Binary Pulsars (HMXBP), in which the companion star is a source of supersonic stellar wind, provide a laboratory to probe the velocity and density profile of such winds. Here, we have measured the variation of the absorption…
The aim of the present investigation is to study the spatio-temporal distribution of precursor flares during the 24-hour interval preceding M- and X-class major flares and the evolution of follower flares. Information on associated…