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Date: 29-8-2020
1253
Date: 25-2-2016
1516
Date: 31-8-2020
1599
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The stellar collider in the Galactic Center
The potential for probing a new regime of stellar dynamics near the MBH in the Galactic Center is best illustrated by comparing the collisional timescale there with that in the cores of the densest globular clusters, which for a long time served as laboratories for the study of collisional processes. In a dense globular cluster, n* ∼ 106 Mּ pc−3 and σ ∼ 10 km s−1, whereas in the Galactic Center, the density may be as high as n* ∼ 108 Mּ pc−3 and σ ∼ 1000 km s−1. The timescale for collisions between solar-type stars in a globular cluster can be estimated to be almost 1010 yr, roughly the age of the Galaxy and of a solar-type star, whereas it is only ∼5×108 yr in the inner 0.02 pc of the Galactic Center. These estimates imply that while physical collisions are only marginally relevant in the cores of the densest globular clusters, they completely dominate the dynamics in the innermost part of the MBH cusp.
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دور النظارات المطلية في حماية العين
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العلماء يفسرون أخيرا السبب وراء ارتفاع جبل إيفرست القياسي
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اختتام المراسم التأبينية التي أهدي ثوابها إلى أرواح شهداء المق*ا*و*مة
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