the $\alpha$-decaying nucleus in selected region close to $^{210}{\rm Po}$ is obtained. An unified formula of the bremsstrahlung probability during the $\alpha$-decay of arbitrary nucleus expressed directly through the $Q_{\alpha}$-value and numbers $A_{p}$, $Z_{p}$ of nucleons and protons of this nucleus is proposed.'
author:
- 'Sergei P. Maydanyuk[^1]'
title: 'Angular bremsstrahlung during $\alpha$-decay, emission from the internal region and unified formula of the bremsstrahlung probability'
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Introduction \[introduction\]
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Last two decades many experimental and theoretical efforts have been made in investigation of nature of bremsstrahlung emission which accompanies $\alpha$-decay of heavy nuclei (see references in [@Maydanyuk.2006.EPJA; @Maydanyuk.2009.NPA]). A key idea of such research consists in search of new information about dynamics of the $\alpha$-decay (and dynamics of tunneling) which is supposed to be extracted from analysis of the measured bremsstrahlung spectra. Tunneling times in nuclear collisions and decays are extremely small, close to nuclear time. This fact results in impossibility to test non-stationary methods of tunneling experimentally. However, researchers open new ways how to obtain new information about the dynamics of nuclear processes. An increasing interest in study of the bremsstrahlung processes accompanying the $\alpha$-decay could be explained by this idea mainly: to find a new approach how through 