A Pre-Merger Stage Galaxy Cluster: Abell 3733

The galaxy cluster Abell 3733 (A3733) is a very suitable candidate in addressing dynamical processes throughout galaxy cluster mergers. This study shows structural analysis results of A3733 (z = 0.038) based on X-ray and optical data. According to X-ray luminosity map, A3733 hosts two sub-structures separated in the sky by $\sim$ 0.25 Mpc, and the two distinct clumps are located in the East (A3733E) and the West (A3733W) directions. Both sub-structures are centred on two different brightest cluster galaxies (BCGs), and the X-ray and optical centroids of both BCGs substantially coincide with each other. The intracluster medium (ICM) temperatures of the sub-structures are estimated to be 2.79 keV for A3733E and 3.28 keV for A3733W. Both sub-structures are found to be hosting cool central gas (kT $\sim$ 1.5-2.5 keV) surrounded by hotter gas (kT $\sim$ 3.0-3.5 keV). Besides, the X-ray concentration parameters are found to be c $\sim$ 0.3 for each sub-structure. These results indicate the existence of cool centres for both sub-structures. The optical density map reveals a crowded galaxy population within the vicinity of A3733W. The high probable (% 88.2) dynamical binding model of A3733 suggests that the cores of sub-structures have a 3D separation of 0.27 Mpc and will collide in 0.14 Gyr with the relative in-falling velocity of 1936 km s$^{-1}$. As a conclusion, this study demonstrates some evidence suggesting that the A3733 system is in the pre-merger state.Comment: 9 pages, 7 Figures, published by MNRA

Thermal QCD Sum Rules Study of Vector Charmonium and Bottomonium States

We calculate the masses and leptonic decay constants of the heavy vector quarkonia, $J/\psi$ and $\Upsilon$ mesons at finite temperature. In particular, considering the thermal spectral density as well as additional operators coming up at finite temperature, the thermal QCD sum rules are acquired. Our numerical calculations demonstrate that the masses and decay constants are insensitive to the variation of temperature up to $T\cong 100 ~MeV$, however after this point, they start to fall altering the temperature. At deconfinement temperature, the decay constants attain roughly to 45% of their vacuum values, while the masses are diminished about 12%, and 2.5% for $J/\psi$ and $\Upsilon$ states, respectively. The obtained results at zero temperature are in good consistency with the existing experimental data as well as predictions of the other nonperturbative models. Considerable decreasing in the values of the decay constants can be considered as a sign of the quark gluon plasma phase transition.Comment: 14 Pages, 8 Figures and 2 Table

Stabilization of Extra Dimensions at Tree Level

By considering the effects of string winding and momentum modes on a time dependent background, we find a method by which six compact dimensions become stabilized naturally at the self-dual radius while three dimensions grow large.Comment: 15 pages, 2 figures, minor typos correcte

Spectral and Rotational Changes in the Isolated Neutron Star RX J0720.4-3125

RX J0720.4-3125 is an isolated neutron star that, uniquely in its class, has shown changes in its thermal X-ray spectrum. We use new spectra taken with Chandra's Low Energy Transmission Grating Spectrometer, as well as archival observations, to try to understand the timescale and nature of these changes. We construct lightcurves, which show both small, slow variations on a timescale of years, and a larger event that occurred more quickly, within half a year. From timing, we find evidence for a `glitch' coincident with this larger event, with a fractional increase in spin frequency of 5x10^{-8}. We compare the `before' and `after' spectra with those from RX J1308.6+2127, an isolated neutron star with similar temperature and magnetic field strength, but with a much stronger absorption feature in its spectrum. We find that the `after' spectrum can be represented remarkably well by the superposition of the `before' spectrum, scaled by two thirds, and the spectrum of RX J1308.6+2127, thus suggesting that the event affected approximately one third of the surface. We speculate the event reflects a change in surface composition caused by, e.g., an accretion episode.Comment: 4 pages, 2 figures, 2 tables, emulateapj format. ApJL, accepte

Feeding habits of garfish, Belone belone euxini Günther, 1866 in autumn and winter in Turkey’s south–east coast of the Black Sea

Hábitos alimentarios de la aguja, Belone belone auxini Günther, 1866 en otoño e invierno en la costa suroriental del Mar Negro, en Turquía En el estudio se examinó el contenido estomacal de Belone belone en la costa suroriental del Mar Negro durante los meses de otoño e invierno de 2010 y 2011. Las hormigas voladoras constituyeron la presa más frecuente de la dieta en otoño, mientras que en invierno fueron los peces. Otras presas que aparecen en la dieta son moluscos, crustáceos e isópodos. Las hormigas voladoras son consumidas básicamente por los machos, en especial por los más pequeños, durante el otoño.Hábitos alimentarios de la aguja, Belone belone auxini Günther, 1866 en otoño e invierno en la costa suroriental del Mar Negro, en Turquía En el estudio se examinó el contenido estomacal de Belone belone en la costa suroriental del Mar Negro durante los meses de otoño e invierno de 2010 y 2011. Las hormigas voladoras constituyeron la presa más frecuente de la dieta en otoño, mientras que en invierno fueron los peces. Otras presas que aparecen en la dieta son moluscos, crustáceos e isópodos. Las hormigas voladoras son consumidas básicamente por los machos, en especial por los más pequeños, durante el otoño.We studied the stomach content of Belone belone in the south–east Black Sea during autumn and winter months in 2010–2011. The most frequent feeding items in the diet were insects in autumn and fish in winter. Other items in the diet were mollusks, crustaceans and isopods. Flying ants were mostly consumed by male garfish, particularly the smaller fish, in autumn

Compliance of the Web-based Distance Training and Consultancy on Individual's Treatment having Suffered Myocardial Infarction and its Effects on Well-being

PMID = 3050183