Spot-focused laser-plasma toward large-scale, line-shaped, uniform monochromatic soft x-ray source

ABSTRACT A variety of large-scale diffuse radio structures have been identified in many clusters with the advent of new state-of-the-art facilities in radio astronomy. Among these diffuse radio structures, radio mini-halos are found in the central regions of cool core clusters. Their origin is still unknown and they are challenging to discover; less than 30 have been published to date. Based on new VLA observations, we confirmed the mini-halo in the massive strong cool core cluster PKS 0745−191 (z = 0.1028) and discovered one in the massive cool core cluster MACS J1447.4+0827 (z = 0.3755). Furthermore, using a detailed analysis of all known mini-halos, we explore the relation between mini-halos and active galactic nucleus (AGN) feedback processes from the central galaxy. We find evidence of strong, previously unknown correlations between mini-halo radio power and X-ray cavity power, and between mini-halo and the central galaxy radio power related to the relativistic jets when spectrally decomposing the AGN radio emission into a component for past outbursts and one for ongoing accretion. Overall, our study indicates that mini-halos are directly connected to the central AGN in clusters, following previous suppositions. We hypothesize that AGN feedback may be one of the dominant mechanisms giving rise to mini-halos by injecting energy into the intra-cluster medium and reaccelerating an old population of particles, while sloshing motion may drive the overall shape of mini-halos inside cold fronts. AGN feedback may therefore not only play a vital role in offsetting cooling in cool core clusters, but may also play a fundamental role in re-energizing non-thermal particles in clusters.

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X-Ray Emission Differences in SNR MSH14-63

Highlights of Astronomy ◽

10.1017/s1539299600021432 ◽

1998 ◽

Vol 11 (1) ◽

pp. 393-393

Author(s):

Fangjun Lu ◽

Mei Wu ◽

Tipei Li ◽

Xuejun Sun

Keyword(s):

Large Scale ◽

Physical Characteristics ◽

Energy Bands ◽

X Ray

In the paper we report the discovery of X-ray emission differences in SNR MSH14-63 based on the ROSAT PSPC observation. The structures of MSH14-63 are different in different energy bands. These images along with the radial brightness distributions in these energy bands show the existence of a region which only emit X-ray photons harder than l.OkeV. Though weak, there actually exist large scale X-ray emissions beyond the bright rim in many parts of the northeast remnant component, which is in conflict with the Sedov phase assumption used in previous research. These new soft X-ray features provide astronomers more information to study its physical characteristics.

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The Hot Universe with XRISM and Athena

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318007792 ◽

2018 ◽

Vol 14 (S342) ◽

pp. 29-36

Author(s):

M. Guainazzi ◽

M. S. Tashiro

Keyword(s):

Electromagnetic Radiation ◽

Large Scale ◽

Cosmological Evolution ◽

X Ray ◽

Hot Gas ◽

Cosmic Vision ◽

Esa Cosmic Vision ◽

The Universe

AbstractX-ray spectroscopy is key to address the theme of “The Hot Universe”, the still poorly understood astrophysical processes driving the cosmological evolution of the baryonic hot gas traceable through its electromagnetic radiation. Two future X-ray observatories: the JAXA-led XRISM (due to launch in the early 2020s), and the ESA Cosmic Vision L-class mission Athena (early 2030s) will provide breakthroughs in our understanding of how and when large-scale hot gas structures formed in the Universe, and in tracking their evolution from the formation epoch to the present day.

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Multinational Enterprises and the Globalization of Medicine: Siemens and the Business of X-ray Equipment in Non-Western Markets, 1900–1939

Enterprise & Society ◽

10.1017/s1467222700016128 ◽

2014 ◽

Vol 15 (4) ◽

pp. 820-848

Author(s):

Pierre-Yves Donzé

Keyword(s):

International Organizations ◽

Multinational Enterprises ◽

Large Scale ◽

Multinational Enterprise ◽

Central Africa ◽

Great Difficulty ◽

X Ray ◽

Hospital Development ◽

Slight Growth ◽

The 19Th Century

Whereas the globalization of medicine since the middle of the 19th century has primarily been approached as the sociopolitical and cultural outcome of imperialism, this article argues that Western big business also played a major role through the worldwide export of standardized medical technologies. It focuses on the expansion of Siemens on the X-ray equipment market in non-Western countries during the first half of the twentieth century. This German multinational enterprise experienced slight growth from the mid-1920s onwards but relied mainly on two markets (Argentina and Brazil). It specialized in providing large-scale equipment to a few urban hospitals and engaged during the 1930s in large-scale hospital development together with local authorities and international organizations in various countries (China, Peru, and Central Africa). However, Siemens had great difficulty in expanding its business to include private doctors and inland outlets, where it faced intense competition from other Western X-ray producers. This paper emphasizes that this shortcoming stemmed from a direct application of the European strategy (high-quality, expensive equipment for hospitals) to non-Western markets, where health systems differed.

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Soft-X-ray spectra of highly charged Au ions in an electron-beam ion trap

Canadian Journal of Physics ◽

10.1139/p00-104 ◽

2001 ◽

Vol 79 (2-3) ◽

pp. 153-162 ◽

Cited By ~ 26

Author(s):

E Träbert ◽

P Beiersdorfer ◽

K B Fournier ◽

S B Utter ◽

K L Wong

Keyword(s):

Electron Beam ◽

Beam Energy ◽

Large Scale ◽

Ion Trap ◽

Electron Beam Energy ◽

X Ray ◽

Maximum Charge ◽

Electron Beam Ion Trap ◽

Atomic Structure Calculations ◽

Structure Calculations

Systematic variation of the electron-beam energy in an electron-beam ion trap has been employed to produce soft-X-ray spectra (20 to 60 Å) of Au with well-defined maximum charge states ranging from Br- to Co-like ions. Guided by large-scale relativistic atomic structure calculations, the strongest Δn = 0 (n = 4 to n' = 4) transitions in Rb- to Cu-like ions (Au42+ Au50+) have been identified. PACS Nos.: 32.30Rj, 39.30+w, 31.50+w, 32.20R

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FORMATION OF DARK MATTER HALOES IN A HOMOGENEOUS DARK ENERGY UNIVERSE

International Journal of Modern Physics D ◽

10.1142/s0218271810017561 ◽

2010 ◽

Vol 19 (08n10) ◽

pp. 1397-1403

Author(s):

L. MARASSI

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Large Scale ◽

State Parameter ◽

Mass Function ◽

Accelerated Expansion ◽

X Ray ◽

Energy Models ◽

Dark Energy Component ◽

Standard Press

Several independent cosmological tests have shown evidences that the energy density of the universe is dominated by a dark energy component, which causes the present accelerated expansion. The large scale structure formation can be used to probe dark energy models, and the mass function of dark matter haloes is one of the best statistical tools to perform this study. We present here a statistical analysis of mass functions of galaxies under a homogeneous dark energy model, proposed in the work of Percival (2005), using an observational flux-limited X-ray cluster survey, and CMB data from WMAP. We compare, in our analysis, the standard Press–Schechter (PS) approach (where a Gaussian distribution is used to describe the primordial density fluctuation field of the mass function), and the PL (power–law) mass function (where we apply a non-extensive q-statistical distribution to the primordial density field). We conclude that the PS mass function cannot explain at the same time the X-ray and the CMB data (even at 99% confidence level), and the PS best fit dark energy equation of state parameter is ω = -0.58, which is distant from the cosmological constant case. The PL mass function provides better fits to the HIFLUGCS X-ray galaxy data and the CMB data; we also note that the ω parameter is very sensible to modifications in the PL free parameter, q, suggesting that the PL mass function could be a powerful tool to constrain dark energy models.

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