Chandra Estimate of the Magnetic Field Strength near the Cold Front in A3667

摘要: We use the Chandra observation of cold front in intracluster gas A3667 to estimate magnetic field strength near front. The is seen data as a sharp discontinuity density that delineates large body dense cool moving with near-sonic velocity through less dense, hotter gas. Without field, should be quickly disturbed by Kelvin-Helmholtz instability arising from tangential motion layers. However, image shows stable within ±30° sector direction cloud motion, beyond which it gradually disappears. suggest suppressed surface tension whose lines are parallel required B ~ 10 μG. expected stronger and have very different structure compared bulk intergalactic medium because stretched motions. Such configuration, once formed, would effectively stop plasma diffusion heat conduction across may inhibit mixing during subcluster merger. note even increased contributes only 10%-20% total pressure, therefore pressure unimportant for hydrostatic cluster mass estimates.