Search Publications

The study of umbral dots in sunspots based on SOT/Hinode observations

Ebadi, H.; Abbasvand, V.; Pourjavadi, H.

To understand the energy transport in sunspots, it is necessary to investigate the dynamic properties of umbral dots (UDs). In this connection, we used high-resolution SOT/Hinode time-series images. The intensity oscillations of UDs are determined. We conclude that their periods are in the range of 3-5 min, which may be related to the propagation …

Future perspectives for abundance measurements in clusters of galaxies with XMM-Newton

Mernier, F.; de Plaa, J.

The CHEERS (CHEmical enrichment reflection grating spectrometer sample) observations of clusters of galaxies with XMM-Newton have shown to be valuable to constrain the chemical evolution of the universe. The soft X-ray spectrum contains lines of the most abundant metals from N to Ni, which provide relatively accurate abundances that can be compare…

Stellar X‑ray accretion signatures

Robrade, J.; Günther, H. M.; Schneider, P. C.

X-ray studies of solar system objects: Past, present, and the next decade

Branduardi-Raymont, G.

This paper presents an overview of the remarkable progress that X-ray studies of solar system objects have delivered over the past three decades, covering research that encompasses remote observations with XMM-Newton and Chandra, in situ measurements by planetary missions, and models of solar wind propagation from 1 AU. The future of X-ray explora…

Evolution of clusters and cosmology

Arnaud, M.

Recent Sunyaev-Zeldovich (SZ) surveys (ACT, Planck, SPT) have provided new cluster catalogs, very significantly expanding the coverage of the mass-redshift plane, while XMM-Newton surveys are pushing cluster detection to lower masses, up to z ∼ 1 and beyond. Cosmological analysis of the new cluster samples, particularly that of the largest Planck …

Unveiling multiple AGN activity in galaxy mergers

Bianchi, S.; Guainazzi, M.; Vignali, C. +13 more

In this paper we present an overview of the MAGNA (Multiple AGN Activity) project aiming at a comprehensive study of multiple super-massive black hole systems. With the main goal of characterizing the sources in merging systems at different stages of evolution, we selected a sample of objects optically classified as multiple systems on the basis o…

Leveraging high‑resolution spectra to understand black hole spectra

Nowak, M. A.

For the past 17 years, both XMM-Newton and Chandra have brought the powerful combination of high spatial and spectral resolution to the study of black hole systems. Each of these attributes requires special consideration--- in comparison to lower spatial resolution, CCD quality spectra--- when modeling observations obtained by these spacecraft. A …

Is the Pollock's paradigm of X-ray emission for O stars correct?

Kholtygin, A. F.; Ryspaeva, E. B.

We considered the mechanism of the formation of the X-ray emission for massive stars. The X-ray spectra of 25 O stars were extracted from the archive of XMM-Newton data obtained in 2000-2014. We determined the distribution of the ratio of half-width at half-maximum to the wind terminal velocity for strong isolated spectral lines in the spectra of …

Cosmic X-ray surveys of active galactic nuclei: The synergy between X-ray and infrared observations

Alexander, D. M.

We briefly review the synergy between X-ray and infrared observations for Active Galactic Nuclei (AGNs) detected in cosmic X-ray surveys, primarily with XMM-Newton, Chandra, and NuSTAR. We focus on two complementary aspects of this X-ray-infrared synergy (1) the identification of the most heavily obscured AGNs and (2) the connection between star f…

The legacy of Stripe 82X in the next decade of XMM ‑Newton

LaMassa, S. M.