What is gamma decay ? Explain by proper example.
The process of $\gamma$-ray (photon) emission during the disintegration of a radioactive nucleus is called gamma decay.
$\gamma$-ray emitted in gamma decay has no mass and charge so the mass number of the daughter nucleus does not change. Its general equation is as follows:
${ }_{\mathrm{Z}}^{\mathrm{A}} \mathrm{X} \rightarrow{ }_{\mathrm{Z}}^{\mathrm{A}} \mathrm{X}+{ }_{0} \gamma^{0}$
$\text { Excited }$ $\text{ state}\text { Ground }$ $\text { state }$
where left side nucleus $\mathrm{Z}^{\mathrm{A}}$ is in excited state.
right side nucleus $\mathrm{Z}^{\mathrm{A}}$ is in ground state.
Atomic energy level spacing are of the order of $\mathrm{eV}$, while the difference in nuclear energy levels is of the order of $\mathrm{MeV}$.
When a nucleus in an excited state spontaneously decays to its ground state (or to a lower energy state), a photon is emitted with energy equal to the difference in the two energy levels of the nucleus. This is the so called gamma decay.
The energy $(\mathrm{MeV})$ corresponds to radiation of extremely short wavelength, shorter than the hard $X$-ray region.
Typically a $\gamma$-ray is emitted when a $\alpha$ or $\beta$ decay results in a daughter nucleus in an excited state.
This daughter nucleus then returns to the ground state by a single photon transition or successive transitions involving more than one photon.
The radioactive decay of uranium into thorium is expressed by the equation $_{92}^{238}U \to _{90}^{234}Th + X,$ where $'X'$ is
In the given nuclear reaction $A, B, C, D, E$ represents
$_{92}{U^{238}}{\xrightarrow{\alpha }_B}T{h^A}{\xrightarrow{\beta }_D}P{a^C}{\xrightarrow{E}_{92}}{U^{234}}$
In the disintegration series
$_{92}^{238}U\xrightarrow{\alpha }x\xrightarrow{\beta }_Z^AY$
The value of $Z$ and $A$ respectively will be
In a radioactive decay, neither the atomic number nor the mass number changes. Which of the following would be emitted in the decay process
A radioactive nucleus undergoes a series of decay according to the scheme
$A\xrightarrow{\alpha }{{A}_{1}}\xrightarrow{\beta }{{A}_{2}}\xrightarrow{\alpha }{{A}_{3}}\xrightarrow{\gamma }{{A}_{4}}$
If the mass number and atomic number of $A$ are $180$ and $72$ respectively, then what are these number for $A_4$