English
Related papers

Related papers: Spectral Implications of Atomic Uncertainties in O…

200 papers

The high-intensity version of multiwavelength anomalous diffraction (MAD) has a potential for solving the phase problem in femtosecond crystallography with x-ray free-electron lasers (XFELs). For MAD phasing, it is required to calculate or…

Atomic Physics · Physics 2017-02-16 Sang-Kil Son , Henry N. Chapman , Robin Santra

New X-ray observatories (Chandra and XMM-Newton) are providing a wealth of high-resolution X-ray spectra in which hydrogen- and helium-like ions are usually strong features. We present results from a new collisional-radiative plasma code,…

Astrophysics · Physics 2009-11-06 Randall K. Smith , Nancy S. Brickhouse , Duane A. Liedahl , John C. Raymond

We review the available atomic data used for interpreting and modeling X-ray observations. The applications for these data can be divided into several levels of detail, ranging from compilations which can be used with direct inspection of…

Astrophysics · Physics 2008-11-26 T. R. Kallman , P. Palmeri

While Gamma Ray Bursts (GRBs) have the potential to shed light on the astrophysics of jets, compact objects, and cosmology, a major set back in their use as probes of these phenomena stems from our incomplete knowledge surrounding their…

High Energy Astrophysical Phenomena · Physics 2024-08-12 Tyler Parsotan , Davide Lazzati

We compute X-ray emission lines from thermal plasma in hot accretion flows. We show that line profiles are strong probes of the gas dynamics, and we present line-ratio diagnostics which are sensitive to the distribution of mass with…

Astrophysics · Physics 2009-10-31 Rosalba Perna , John Raymond , Ramesh Narayan

The new spectroscopic method for measurement of hot plasma parameters is developed. The method based on Ha profile monitoring. The profile was accurately calculated for a wide range of plasma parameters (n$_e \sim $ 10$^{14} \div $…

Plasma Physics · Physics 2007-05-23 P. I. Melnikov , I. A. Ivanov

From hot, tenuous gas dominated by Compton processes, to warm, photoionized emission-line regions, to cold, optically thick fluorescing matter, accreting gas flows in X-ray binaries span a huge portion of the parameter space accessible to…

Astrophysics · Physics 2007-05-23 Duane A. Liedahl , Patrick S. Wojdowski , Mario A. Jimenez-Garate , Masao Sako

The Vienna Atomic Line Database (VALD) has been supplemented with new data and new functionality -- the possibility of taking into account the effect of hyperfine splitting (HFS) of atomic levels in the analysis of line profiles. This has…

Instrumentation and Methods for Astrophysics · Physics 2019-11-11 Yu. V. Pakhomov , T. A. Ryabchikova , N. E. Piskunov

The composition in terms of nuclear species of the primary cosmic ray flux is largely uncertain in the knee region and above, where only indirect measurements are available. The predicted fluxes of high-energy leptons from cosmic ray air…

High Energy Astrophysical Phenomena · Physics 2019-12-24 L. A. Fusco , F. Versari

Numerical Monte Carlo simulations of the diffusive shock acceleration in the test particle limit are investigated. We simulate high relativistic flow astrophysical plasmas for upstream $\gamma$ $\sim5$ and up to $\gamma$ $\sim1000$. These…

Astrophysics · Physics 2007-05-23 Athina Meli , John Quenby

When matter is exposed to a high-intensity x-ray free-electron-laser pulse, the x rays excite inner-shell electrons leading to the ionization of the electrons through various atomic processes and creating high-energy-density plasma, i.e.,…

Atomic and Molecular Clusters · Physics 2017-08-24 Malik Muhammad Abdullah , Anurag , Zoltan Jurek , Sang-Kil Son , Robin Santra

This paper explores optimal methods for obtaining one-dimensional (1D) powder pattern intensities from two-dimensional (2D) planar detectors with good estimates of their standard deviations. We describe methods to estimate uncertainties…

Materials Science · Physics 2014-09-12 Xiaohao Yang , Pavol Juhas , Simon J. L. Billinge

Advances in our ability to understand and utilize the world around us have always relied on the development of advanced tools for probing and manipulating materials properties. X-ray matter interactions played a critical role in the…

Materials Science · Physics 2021-08-13 Mariano Trigo , Mark P. M. Dean , David A. Reis

We report the discovery of a luminosity distance estimator using Active Galactic Nuclei (AGN). We combine the correlation between the X-ray variability amplitude and the Black Hole (BH) mass with the single epoch spectra BH mass estimates…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Fabio La Franca , Stefano Bianchi , Gabriele Ponti , Enzo Branchini , Giorgio Matt

With its array of 3840 Transition Edge Sensors (TESs) operated at 90 mK, the X-Ray Integral Field Unit (X-IFU) on board the ESA L2 mission Athena will provide spatially resolved high-resolution spectroscopy (2.5 eV FWHM up to 7 keV) over…

X-ray spectroscopy is a powerful technique for the analysis of the energy distribution of X-rays from astrophysical sources. It allows for the study of the properties, composition, and physical processes taking place at the site of…

High Energy Astrophysical Phenomena · Physics 2023-09-22 L. Ducci , C. Malacaria

We present strategies to quantify theoretical uncertainties in modern ab-initio calculations of electromagnetic observables in light and medium-mass nuclei. We discuss how uncertainties build up from various sources, such as the…

The Soft X-ray Spectrometer (SXS) on board \textit{Hitomi}, with the unprecedented resolving power of R$\sim$1250, allowed the detection of members of the Fe XXV \ka\ complex emission spectra from the center of the Perseus Cluster. In this…

High Energy Astrophysical Phenomena · Physics 2020-09-30 P. Chakraborty , M. Chatzikos , F. Guzmán , Y. Su , G. J. Ferland

Measuring the relative amount of high-temperature, low-emission-measure plasma is considered to be a smoking gun observation to constrain the frequency of plasma heating in coronal structures. Often, narrowband, extreme ultraviolet images,…

Solar and Stellar Astrophysics · Physics 2024-01-24 P. S. Athiray , Amy R. Winebarger

We present the science case for a broadband X-ray imager with high-resolution spectroscopy, including simulations of X-ray spectral diagnostics of both active regions and solar flares. This is part of a trilogy of white papers discussing…