scholarly journals Non-thermal X-rays, a high-abundance ridge and fossil bubbles in the core of the Perseus cluster of galaxies

2005 ◽  
Vol 360 (1) ◽  
pp. 133-140 ◽  
Author(s):  
J. S. Sanders ◽  
A. C. Fabian ◽  
R. J. H. Dunn
2008 ◽  
Vol 4 (S259) ◽  
pp. 567-568
Author(s):  
Diego Falceta-Gonçalves ◽  
E. M. de Gouveia dal Pino ◽  
J. Gallagher ◽  
A. Lazarian

AbstractThe Perseus Cluster (A426) is the brightest cluster of galaxies observed in X-rays in the sky and its giant central galaxy (NGC1275) hosts the extended double radio source 3C84. There is a spectacular H-alpha nebulosity surrounding NGC1275 with loops and filaments that are probably magnetized and extend over 100 kpc. The continuous blowing of bubbles leading to the propagation of shock fronts is also evident and more recently, outflow and infall velocities of several 1000 km/s have been detected associated to the surrounding filaments. We here present preliminary results of 2.5D MHD simulations of the Perseus cluster central region assuming that the production of the outflow structures and loops that arise from the surface of NGC1275 are due to turbulent injection triggered by recent star formation and SNe activity in the galaxy. This is in turn, probably induced by a continuous gas infall from the satellite galaxies around NGC1275. Our simulations which include both, the turbulent gas outflow and gas infall from the surroundings, have revealed a continuous formation of the observed features, like the filaments, the gigantic magnetic loops and weak shock fronts that propagate into the ICM medium with the observed velocities of 1000–5000 km/s. After 10 Myr, a nearly steady state is established between the outflow material emerging from the central galaxy and the inflow gas from the surrounds. The outflow activity seems to retard the cannibalism action of the central galaxy over the surrounding galaxies. This result may have important implications over the evolution of the whole cluster as it seems to indicate that the SF and SNe production that are induced by the cannibalism may help to decelerate the later due to turbulence and outflow production. These results also offer important clues to the hot halo formation in the center of the cluster and in the suppression of cooling flows.


1976 ◽  
Vol 208 ◽  
pp. 1 ◽  
Author(s):  
R. S. Wolff ◽  
R. J. Mitchell ◽  
P. A. Charles ◽  
J. L. Culhane

1981 ◽  
Vol 248 ◽  
pp. 47 ◽  
Author(s):  
A. C. Fabian ◽  
E. M. Hu ◽  
L. L. Cowie ◽  
J. Grindlay
Keyword(s):  
X Ray ◽  
The Core ◽  

2008 ◽  
Vol 385 (3) ◽  
pp. 1186-1200 ◽  
Author(s):  
J. S. Sanders ◽  
A. C. Fabian ◽  
S. W. Allen ◽  
R. G. Morris ◽  
J. Graham ◽  
...  
Keyword(s):  
X Ray ◽  
The Core ◽  

2016 ◽  
Vol 12 (S329) ◽  
pp. 362-365
Author(s):  
Norbert S. Schulz

AbstractMost cores of very young stellar clusters contain one or more massive stars at various evolutionary stages. Observations of the Orion Nebula Cluster, Trumpler 37, NGC 2362, RCW38, NGC 3603 and many others provide the most comprehensive database to study stellar wind properties of these massive cluster stars in X-rays. In this presentation we review some of these observations and results and discuss them in the context of stellar winds and possible evolutionary implications. We argue that in very young clusters such as RCW38 and M17, shock heated remnants of a natal shell could serve as an alternate explanation to the colliding wind paradigm for the hot plasma components in the X-ray spectra.


2014 ◽  
Vol 171 ◽  
pp. 93-111 ◽  
Author(s):  
Bridgette Cooper ◽  
Přemysl Kolorenč ◽  
Leszek J. Frasinski ◽  
Vitali Averbukh ◽  
Jon P. Marangos

Ultrafast hole dynamics created in molecular systems as a result of sudden ionisation is the focus of much attention in the field of attosecond science. Using the molecule glycine we show through ab initio simulations that the dynamics of a hole, arising from ionisation in the inner valence region, evolves with a timescale appropriate to be measured using X-ray pulses from the current generation of SASE free electron lasers. The examined pump–probe scheme uses X-rays with photon energy below the K edge of carbon (275–280 eV) that will ionise from the inner valence region. A second probe X-ray at the same energy can excite an electron from the core to fill the vacancy in the inner-valence region. The dynamics of the inner valence hole can be tracked by measuring the Auger electrons produced by the subsequent refilling of the core hole as a function of pump–probe delay. We consider the feasibility of the experiment and include numerical simulation to support this analysis. We discuss the potential for all X-ray pump-X-ray probe Auger spectroscopy measurements for tracking hole migration.


2007 ◽  
Vol 3 (S244) ◽  
pp. 350-351
Author(s):  
L. Cortese ◽  
R. F. Minchin ◽  
R. R. Auld ◽  
J. I. Davies ◽  
B. Catinella ◽  
...  

AbstractWe present 21 cm observations of 5×1 square degrees centered on the local Abell cluster 1367 obtained as part of the Arecibo Galaxy Environment Survey. This represents the first HI selected sample covering the core and the outskirts of a local cluster of galaxies. Combining the HI data with SDSS optical imaging we show that in HI selected samples follow scaling relations similar to the ones usually observed in optically selected samples. The most striking difference between HI and optically selected samples resides in their large scale distribution: while optical and X-ray observations trace the cluster potential very well, at radio wavelengths there is almost no evidence of the cluster presence.


2004 ◽  
Vol 03 (03) ◽  
pp. 281-292 ◽  
Author(s):  
J. NAYAK ◽  
S. VARMA ◽  
D. PARAMANIK ◽  
S. N. SAHU

The synthesis of the GaAs nanoparticles, having sizes 7 nm to 15 nm, by a low cost electrochemical technique has been reported. The absence of any foreign impurity has been confirmed by the Proton-Induced X-rays Emission analysis. Rutherford Backscattering measurement has been performed in order to estimate the thickness of the nanoparticle-generated thin film as a function of the electrolysis current density. The X-ray Photoelectron Spectroscopic study confirms the formation of GaAs and exhibits the binding energy shift of the core shell electrons as an implication of the nanostructure effect. Very weak infrared luminescence due to the radiative recombination of the impurity bound exciton has been detected from yttrium-doped GaAs nanocrystals, even at room temperature.


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