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arXiv · 2009.03084

Non-extensive processes associated with heating of the Galactic disc

C. A. P. Viana·D. B. de Freitas
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Abstract

We analyse the mechanisms ruling galactic disc heating through the dynamics of space velocities $U$, $V$ and $W$, extracted from the Geneva-Copenhagen catalogue. To do this, we use a model based on non-extensive statistical mechanics, where we derive the probability distribution functions that quantify the non-Gaussian effects. Furthermore, we find that the deviation $q-1$ at a given stellar age follows non-random behaviour. As a result, the $q$-index behaviour indicates that the vertical component $W$, perpendicular to the Galactic plane, does not ``heat up'' at random, which is in disagreement with previous works that attributed the evolution of $W$ to randomness. Finally, our results bring a new perspective to this matter and open the way for studying Galactic kinematic components through the eyes of more robust statistical models that consider non-Gaussian effects.

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C. A. P. Viana, D. B. de Freitas. 2020-09-07. Non-extensive processes associated with heating of the Galactic disc. https://doi.org/10.1209/0295-5075/131/69002

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