اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدCavities, shocks and a cold front around 3C 320
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Nilkanth D. Vagshette
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We present results obtained from the analysis of a total of 110 ks Chandra observations of 3C 320 FR II radio galaxy, located at the centre of a cluster of galaxies at a redshift $z=0.342$. A pair of X-ray cavities have been detected at an average distance of $sim$38 kpc along the East and West directions with the cavity energy, age and total power equal to $sim$7.7$times$10$^{59}$ erg, $sim$7$times$10$^7$ yr and $sim$3.5$times$10$^{44}$ erg s$^{-1}$, respectively. The cooling luminosity within the cooling radius of $sim$100 kpc was found to be $L_{cool} sim8.5times10^{43}$ erg s$^{-1}$. Comparison of these two estimates implies that the cavity power is sufficiently high to balance the radiative loss. A pair of weak shocks have also been evidenced at distances of $sim$47 kpc and $sim$76 kpc surrounding the radio bubbles. Using the observed density jumps of $sim$1.8 and $sim$2.1 at shock locations along the East and West directions, we estimate the Mach numbers ($mathcal{M}$) to be $sim$1.6 and $sim$1.8, respectively. A sharp surface brightness edge was also detected at relatively larger radius ($sim$80 kpc) along the South direction. Density jump at this surface brightness edge was estimated to be $sim$1.6 and is probably due to the presence of a cold front in this cluster. The far-infrared luminosity yielded the star formation rate of 51 M$_{odot}$ yr$^{-1}$ and is 1/4$^{th}$ of the cooling rate ($dot{M}$ $sim$ 192 M$_{odot}$ yr$^{-1}$).
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