Pulse height defect

Haines, E.L., Whitehead, A.B. Pulse height defect and energy dispersion in semiconductor detectors. Rev. Sci. Instrum. 37,190 (1966)... 

For heavy ions, a phenomenon called the pulse height defect (PHD) seems to have an important effect on energy calibration. As a result of the PHD, the relationship between pulse height and ion energy is mass dependent. In semiconductor detectors, experiments have shown that the PHD depends on the... 

This chapter discusses the subjects of energy loss and straggling, pulse height defect, energy calibration methods, and source preparation, from the point of view of their effect on spectroscopy. All the effects are not equally important for all types of particles. Based on similarity in energy loss behavior, the charged particles are divided into three groups, as in Chap. 4 ... 

Heavy-ion spectroscopy is different from that of lighter charged particles because of the pulse-height defect (PHD), which makes the energy calibration equation mass dependent. 

Figure 13.18 The dependence of the pulse height defect on ion energy (from Ref. 33). The numbers correspond, approximately, to uranium ions.

The lack of nuclear collisions for channeled ions is not the only phenomenon that affects the pulse height. It is known that the electron density is much reduced along the channel. As a result, the electronic stopping power is lower and, consequently, so is the charge density produced by the heavy ion. Thus, not only the nuelear but also the recombination defect is reduced for the channeled ions. 

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