The name is absent

Chapter 3

Here M_z⁰ is equilibrium magnetization in longitude direction. Λ4_xy(2r) is
magnetization in longitude direction and transverse plane at time 2τ.

In this case, stimulated spin-echo PGSE sequence is used ^t13,_l as shown in
Figure 3.3 ^[14]. The sequence is useful for systems with significantly different
longitudinal (T↑) and transverse (T₂) relaxation times (T↑ > T₂). This is often the
case for systems with large interfacial area, such as emulsions.

90®                  90®                     90®

Figure 3.3 Sequence of stimulated spin-echo PGSE measurement

The sequence begins with a 90° rf pulse to be rotated to transverse plane,
followed by a magnetic gradient pulse. The spins undergo transverse relaxation
T₂. The second 90° rf pulse follows, moving the spins into the longitudinal
direction, where they undergo longitudinal relaxation (Ti). The last 90° pulse
moves the spins back to the transverse plane, followed by a second magnetic
gradient pulse. The result is an echo, referred to as a stimulated echo. The
spin-echo signal amplitude as the function of echo spacing is ^[6]:

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