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Two transition probability

Note that in this case is completely specified by the two transition probabilities... [Pg.415]

Since htjkT is small, the ratio of the two transition probabilities is small and Amn Bmn p (vam). This condition is obtained in the microwave region and is utilized in the construction of masers (microwave amplification by stimulated emission of radiation). [Pg.51]

The essential difference between the two transition probability densities lies in the fact that for the gaussian distribution pw r, ) the different moments E[Xm], m = 1, 2,. . . , n, exist, while for the Cauchy distribution pc(j, x) they do not exist. The Levy distributions characterized by p(t, k) = exp -a k qT) with 0< <2U 127 128 play a prominent role in the theory of relaxation processes.129 133... [Pg.85]

For this reason, first-order Markov mechanisms for the general (asymmetric) case are described in terms of two transition probabilities, e.g., Pa/b and pb/a. These two transition probabilities can be calculated from experimentally determined mole fractions using Equations (15-35)-( 15-37). They may not simultaneously be zero. From Equations (15-27) and (15-28) it follows thatPb/b >Pa/b whenpa/a >Pb/a, and there is a tendency to form both long A chains and long B chains (see Figure 15-2). [Pg.61]

The expanding plasma plume of evaporated material emits fluorescence when excited on an aluminium line at It = 555 nm and on a copper line at A. = 324 nm. The intensity ratio of the total LIE excited by these lines is 1 4. The ratio of the two transition probabilities is 1 6. Calculate the relative abundance of the two atomic species. [Pg.82]

The Bernoullian process is therefore defined for a copolymer by two transition probabilities, and Pg, which reflect the mole fractions of monomers A and B within the resulting copolymer. Given the two addition probabilities, the mole fraction of any given sequence can be calculated straightforwardly. Thus, for example, the abundance of an A A dyad is given by P, whilst that of an AB dyad is equal to 2P P (the factor of two arises because the AB dyad represents both AB and BA sequences). Table 2.2 shows the set of Bernoullian expressions for the three dyad and six triad sequences in an A/B copolymer. [Pg.54]

Example 6 First, we will notice that there are many Markov chains that will have the same long-run distribution. We have two transition probability matrices Pi and P2 that describe the movement through a finite state-space with five elements. They are ... [Pg.115]

The transition probability for absorption of two photons can be described in tenns of a two-photon cross section 5 by... [Pg.1146]

There are two basic physical phenomena which govern atomic collisions in the keV range. First, repulsive interatomic interactions, described by the laws of classical mechanics, control the scattering and recoiling trajectories. Second, electronic transition probabilities, described by the laws of quantum mechanics, control the ion-surface charge exchange process. [Pg.1801]

The Landau-Zener transition probability is derived from an approximation to the frill two-state impact-parameter treatment of the collision. The single passage probability for a transition between the diabatic surfaces H, (/ ) and R AR) which cross at is the Landau-Zener transition probability... [Pg.2052]

The transition probabilities obtained due to the above two modified beat-ments of single-surface calculations need to be compared with those riansition probabilities obtained by two surface calculations that confirms the validity of these former heatments. [Pg.46]

In [66], we have reported inelastic and reactive transition probabilities. Here, we only present the reactive case. Five different types of probabilities will be shown for each transition (a) Probabilities due to a full tri-state calculation carried out within the diabatic representation (b) Probabilities due to a two-state calculation (for which T] = 0) performed within the diabatic representation (c) Probabilities due to a single-state extended BO equation for the N = 3 case (to, = 2) (d) Probabilities due to a single-state extended BO equation for the N = 2 case (coy =1) (e) Probabilities due to a single-state ordinary BO equation when coy = 0. [Pg.71]

The ordinary BO approximate equations failed to predict the proper symmetry allowed transitions in the quasi-JT model whereas the extended BO equation either by including a vector potential in the system Hamiltonian or by multiplying a phase factor onto the basis set can reproduce the so-called exact results obtained by the two-surface diabatic calculation. Thus, the calculated hansition probabilities in the quasi-JT model using the extended BO equations clearly demonshate the GP effect. The multiplication of a phase factor with the adiabatic nuclear wave function is an approximate treatment when the position of the conical intersection does not coincide with the origin of the coordinate axis, as shown by the results of [60]. Moreover, even if the total energy of the system is far below the conical intersection point, transition probabilities in the JT model clearly indicate the importance of the extended BO equation and its necessity. [Pg.80]

Jaquet and Miller [1985] have studied the transfer of hydrogen atom between neighbouring equilibrium positions on the (100) face of W by using a model two-dimensional chemosorption PES [McGreery and Wolken 1975]. In that calculation, performed for fairly high temperatures (T> rj the flux-flux formalism along with the vibrationally adiabatic approximation (section 3.6) were used. It has been noted that the increase of the coupling to the lattice vibrations and decrease of the frequency of the latter increase the transition probability. [Pg.112]

At each Monte Carlo step (MCS), either a dimer is formed from two adjacent monomers or a monomer is added or deleted from the chain end. The transition probabilities are... [Pg.515]

Table 8.8 A list of all (independent) elementary 1-dimensional k = 2,r = V rules supporting a QCA-II quantum dynamical analogue of the form defined by equations (5.4) and (5.7). Two additional rules, 51 and 204, both of class-2, yield pii= 0 and 1 , respectively, so that their q-behavior remains essentially classical, (pn is the a= - a = transition probability which defines the quantum operator 4). Table 8.8 A list of all (independent) elementary 1-dimensional k = 2,r = V rules supporting a QCA-II quantum dynamical analogue of the form defined by equations (5.4) and (5.7). Two additional rules, 51 and 204, both of class-2, yield pii= 0 and 1 , respectively, so that their q-behavior remains essentially classical, (pn is the a= - a = transition probability which defines the quantum operator 4).
Problem—Show that the capacities of the two ohannels below are as given. The numbers on the lines between input and output are the transition probabilities, Pr yj xk)... [Pg.211]

Channels with Continuous Input and Output. Let the channel input alphabet be the set of real numbers. Temporarily we will assume the input, a , to be bounded between two limits, A < x B. We will also assume that a channel transition probability density, Pr(y x), exists which is a continuous function of both x and y. [Pg.241]

In a quantum mechanical framework, Postulate 1 remains as stated. It implies that there exists a well-defined connection and correspondence between the labels attributed to the space-time points by each observer, between the state vectors each observer attributes to a given physical system, and between observables of the system. Postulate 2 is usually formulated in terms of transition probabilities, and requires that the transition probability be independent of the frame of reference. It should be stated explicitly at this point that we shall formulate the notion of invariance in terms of the concept of bodily identity, wherein a single physical system is viewed by two observers who, in general, will have different relations to the system. [Pg.665]

The attractive energies 4D(cr/r)6 and ae2/2 r4 have two important effects on the vibrational energy transfer (a) they speed up the approaching collision partners so that the kinetic energy of the relative motion is increased, and (b) they modify the slope of the repulsive part of the interaction potential on which the transition probability depends. By letting m °°, we have completely ignored the second effect while we have over-emphasized the first. Note that Equation 12 is identical to an expression we could obtain when the interaction potential is assumed as U(r) = A [exp (— r/a)] — (ae2/2aA) — D. Similarly, if we assume a modified Morse potential of the form... [Pg.64]

The deterministic and discrete expressions for the slopes, and hence the half-lives, are thus not identical, but since mathematically when x is much smaller than unity (i.e., x transition probability x = Pr is very small compared to 1, the continuous (deterministic) and discrete expressions yield essentially the same values. When Pt is not small compared to 1, the continuous and discrete solutions will differ. For the case Pt = 0.10, the half-life solutions are ti/2 = 6.93 and i/2 = 6.58 iteration, a noticeable difference of 5%. For Pt = 0.01, t /2 = 69.31 and i/2 = 68.97 iterations, there exists a difference of just 0.5%. For still smaller values of Pp, the difference between the two expressions continues to decrease. [Pg.114]

Table 3. Rigid-rotator transition probabilities for two potentials for = 322 meV... Table 3. Rigid-rotator transition probabilities for two potentials for = 322 meV...

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