Speaker
Description
The current status of testing QED in strong and supercritical Coulomb fields is considered. Special attention is paid to tests of QED in the supercritical Coulomb field. It is known that in slow collisions of two bare nuclei with the total charge number exceeding the critical value, $Z_1+Z_2 > Z_c =173$, the initially neutral vacuum can spontaneously decay into a charged vacuum and two positrons. The detection of spontaneous emission of positrons would be a direct proof of this fundamental phenomenon. However, the spontaneous emission of positrons is usually strongly masked by the dynamic (induced) emission of positrons, which is caused by a rapidly changing electromagnetic field created by colliding nuclei. For about three decades, it was believed that the vacuum decay can only be observed in collisions with nuclear sticking, when the nuclei are bound for a period of time due to nuclear forces. But to date, there is no evidence that nuclear sticking occurs in such collisions of heavy ions. However, in our recent papers [1-5] it has been shown that the vacuum decay can be observed without any sticking of the nuclei. This can be done by measuring the probabilities of the creation of positrons or positron spectra for a given set of nuclear trajectories. The results of this study will be presented in the talk.
This work was carried out with the financial support of the RSF grant No. 22-62-00004.
- I.A. Maltsev, V.M. Shabaev, R.V. Popov, Y.S. Kozhedub, G. Plunien, X. Ma, Th. Stohlker, and D.A. Tumakov, Phys. Rev. Lett. 123, 113401 (2019)
- R.V. Popov, V.M. Shabaev, D.A. Telnov, I.I. Tupitsyn, I.A. Maltsev, Y.S. Kozhedub, A.I. Bondarev, N.V. Kozin, X. Ma, G. Plunien, T. Stohlker, D.A. Tumakov, and V.A. Zaytsev, Phys. Rev. D 102, 076005 (2020).
- R.V. Popov, V.M. Shabaev, I.A. Maltsev, D.A. Telnov, N.K. Dulaev, and D.A. Tumakov, Phys. Rev. D 107, 116014 (2023).
- N.K. Dulaev, D.A. Telnov, V.M. Shabaev, Y.S. Kozhedub, I.A. Maltsev, R.V. Popov, and I.I. Tupitsyn, Phys. Rev. D 109, 036008 (2024).
- N.K. Dulaev, D.A. Telnov, V.M. Shabaev, Y.S. Kozhedub, X. Ma, I.A. Maltsev, R.V. Popov, and I.I. Tupitsyn, Phys. Rev. D 111, 016018 (2025).
