Messanae Universitas Studiorum: No conditions. Results ordered -Date Deposited. 2017-03-28T15:57:09ZEPrintshttp://cab.unime.it/images/sitelogo.pnghttp://cab.unime.it/mus/2012-10-02T08:58:56Z2013-01-22T09:54:01Zhttp://cab.unime.it/mus/id/eprint/829This item is in the repository with the URL: http://cab.unime.it/mus/id/eprint/8292012-10-02T08:58:56ZTime analysis of nuclear collisions and decaysVladislav S. Olkhovsky2012-09-20T11:41:54Z2013-04-03T08:18:00Zhttp://cab.unime.it/mus/id/eprint/708This item is in the repository with the URL: http://cab.unime.it/mus/id/eprint/7082012-09-20T11:41:54ZFundamental problems of time in physical and biological systemsThere are analyzed problems of time in physics, mainly in quantum physics, thermodynamics and physics of living matter. Particular attention is given to the problem of the irreversibility of macroscopic and biologic processes in time.Vladislav S. OlkhovskyV. A. Tchinarov2012-09-19T09:28:15Z2012-09-19T09:28:15Zhttp://cab.unime.it/mus/id/eprint/584This item is in the repository with the URL: http://cab.unime.it/mus/id/eprint/5842012-09-19T09:28:15ZLast developments in time analysis of particle and photon tunnellingIt is presented a selfconsistent systematization of various theoretical approaches to defining tunnelling times for non relativistic particles in the light of time as a quantum-mechanical observable. Then the analogy between particle and photon tunnelling and properties of time as an observable in quantum electrodynamics are examined. At last a short analysis of the microwave and optical experiments on tunnelling times is presented.Vladislav S. Olkhovsky2012-09-19T07:52:05Z2012-09-20T10:00:32Zhttp://cab.unime.it/mus/id/eprint/643This item is in the repository with the URL: http://cab.unime.it/mus/id/eprint/6432012-09-19T07:52:05ZTunnelling times and the "hartman effect"In a recent review paper [Phys. Rpeorts 214 (1992) 339] we proposed, within conventional quantum mechanics, new definitions fot the subarrier tunnelling and reflection times. Aims of the present paper are: (i) presenting and analysing the results of various numerical calculations (based on our equations) on the penetration and return times $\left \langle tau_P_e_n \right \rangle $ , $\left \langle tau_R_e_t\right \rangle $ during tunnelling inside a rectangular potential barrier, for various penetration depths $x_f$ ; (ii) putting forth and discussing suitable definitions. Besides of the mean values, also of the variances (or dispersions)$D\tau_T\ $ and $ D\tau_R\ $ for the tima durations of trasmission and reflection processes; (iii) mentioning that our definition $\left \langle tau_T \right \rangle $ for the average transmission time results to constituite an improvemente of the ordinary dwell-time $ \bar tau^D^W\ $ formula: (iv) commenting upon some recent criticism by C.R. Leavens, on the basis of our new numerical results. We stress that our numerical evaluations confirm that our approach implied, and implies, the existence of the Hartman effect: an effect that in these days (due to the theoretical connections between tunnelling and evanescent-wave propagation) is receiving - at Cologne, Berkeley, Florence and Wien - indirect, but quite interesting, experimental verifications. At last we briefly analyze some other definitions of tunnelling times.Vladislav S. OlkhovskyErasmo RecamiAleksandr K. Zaichenko2012-09-18T07:58:24Z2012-09-20T08:39:09Zhttp://cab.unime.it/mus/id/eprint/574This item is in the repository with the URL: http://cab.unime.it/mus/id/eprint/5742012-09-18T07:58:24ZIs it essential for nuclear chronometry of astrophysical processes to consider the decay of the excited radioactive nuclei?It is presented reasonings that the known methods of the nuclear chronometry of the astrophysical and cosmological process have to be revised and corrected, taking into account distinctions between lifetimes of the ground and excited states for radioactive nuclei and also the multiple alternations of the $\gamma-emission$ from excited states and consequent $\gamma-absorptions$ by ground states in large lumps of matter. As a result, the corrected "nuclear clocks" will indicate to smaller values of the durations of real decay processesVladislav S. Olkhovsky2012-09-18T07:56:05Z2012-09-20T08:38:58Zhttp://cab.unime.it/mus/id/eprint/596This item is in the repository with the URL: http://cab.unime.it/mus/id/eprint/5962012-09-18T07:56:05ZRecent developments on time as a quantum-physical observable quantityAnalytical review of developments in researching $time$ as a quantum-physical observable, which is canonically conjugated to energy, is presented. A special attention is devoted to the duality of energy and time operators and also to the verification of time-energy uncertainty relations for continuous and discrete energy spectra.Vladislav S. Olkhovsky2005-03-09Z2012-09-20T08:39:26Zhttp://cab.unime.it/mus/id/eprint/144This item is in the repository with the URL: http://cab.unime.it/mus/id/eprint/1442005-03-09ZTunnelling time-evolution in the investigation of the two-particle transfer and emission enhancement in sub-barrier heavy-ion collisionsWe present the penetration of Gaussian wave-packet probability density, incoming and reflection flux probability density at any depth inside an opaque barrier, finding expressions for the effective tunnelling velocity for the probability density inside the barrier as a function of the relative depth of penetration, the average transition (or penetration) duration, the effective velocity of the probability density flux inside the barrier as a function of the relative depth of penetration. On the base of analysis of this penetration we develop a model of sub-barrier two-particle tranfer and emission enhancement in nuclear collisions which is an alternative to the Josephson nuclear effect model. Some evaluations of the penetration and return time for the tunnelling motion, referring to two-nucleon transfer and emission enhancement in heavy-ion sub-barrier collisions are presented.Giovanni FazioG. GiardinaVladislav S. OlkhovskyV. S. Sergeyev