Page 2 of 4 for Rajesh Kumar

In this lecture, we will start by revisiting the basics of quantum scattering, focusing on partial wave analysis and phase shifts. The graph at the top illustrates the Breit-Wigner resonance curve, which we will discuss in detail after exploring resonance scattering and its role in energy-dependent cross-sections.

Nuclear Reactions

Nuclear reactions can occur when a target nucleus $X$ is bombarded by a particle $a$, resulting in a daughter nucleus $Y$ and an outgoing particle $b$:

Basic Electronics: Semiconductors

In 1839, Becquerel discovered that some materials generate an electric current when exposed to light. This is known as the photoelectric effect and is the basis of operations of solar cells. Solar cells are made of semiconductors.

Note: Semiconductors are materials that act as insulators at low temperatures, but as conductors when energy or heat is available.

Particle Physics: Quarks

Particle Classification

Particle Physics: Conservation Laws

The conservation laws of energy, momentum, and charge govern all processes. In particle physics, additional empirical conservation laws are also crucial. They are:

Conservation of baryon number
Conservation of lepton number
Conservation of strangeness
Conservation of isospin
Conservation of electric charge

Particle Physics: Particle Classification

Japanese physicist Hideki Yukawa proposed in 1935 that the nuclear force is mediated by a new particle, a meson, whose exchange between nucleons causes the force. He predicted its mass to be about 200 times that of an electron, earning him a Nobel Prize in 1949. Because the new particle would have a mass between that of the electron and that of the proton, it was called a meson (from the Greek meso, “middle”)