**3.2 PIXE analysis**

*Ion Beam Techniques and Applications*

elements. These incident beam particles (usually protons) expel internal shell electrons from the target atoms, which results in the emission of characteristic X-rays (**Figure 4**).

Nuclear reaction analysis (NRA) involves the study of sample by irradiating them with select projectile nuclei with very-high-energy ions to induce nuclear reactions in the target nuclei. Targeted samples undergo a nuclear reaction under resonance conditions for a sharply defined resonance energy. The reaction product is usually a nucleus in an excited state, which immediately decays, emitting ionizing

A sum of 19 different commonly sold cigarette brands (locally manufactured (8) and imported (11)) were randomly purchased from the market of Islamabad (**Table 3**).

**2.4 Nuclear reaction analysis (NRA)**

**3. Experiment detail**

**3.1 Sample preparation of tobacco**

radiation that can be analyzed and interpreted (**Figure 5**).

**90**

**Figure 5.** *Typical NRA setup.*

**Figure 4.**

*Schematic of PIXE setup.*

With the approach of atomic-based analytical strategies in the previous 40 years, proton-induced X-ray emission (PIXE) has set up a part of the advanced elemental investigation of various materials [14]. PIXE is a technique with a diverse array of applications in biology, geology, materials science, and others.

The pelletized samples were irradiated with a 3 MeV proton beam from the 5 MV Pelletron Tandem accelerator installed at Experimental Physics Lab, National Centre for Physics, Islamabad. A standard reference material, NIST 1515 (apple leaves, National Institute of Standards and Technology, USA), was taken as the analytical quality control. The analytical outcomes concurred well with the standard qualities (**Table 1**), confirming the steady quality of the analytical outcomes in this work. The collimated proton beam was of 2 mm diameter. Mylar, "funny" filter having 100 μm thick, was used during the measurements, and this reduced the count


### **Table 1.**

*Analytical results for NIST 1515 (μg/g).*

rate ensuring a less than 10% dead time at beam currents of 2–5 nA. No apparent damage in samples was observed after irradiation. A 30 mm2 Si(Li) detector with an energy resolution of 138 eV (FWHM) at 5:9 keV of Mn was used to detect the emitted X-rays. The PIXE data was analyzed using the computer code GUPIXWIN.
