Which decay process does  \({_zX^A} \longrightarrow {_{z-1}Y^A} + {_{1}e^0} + {\nu}\) represents

Content:

Beta Decay: Beta decay is a process in which either a neutron is converted into a proton (β− decay) or a proton is converted into a neutron (β+ decay). During  β− decay, an electron and a new particle named antineutrino are created and emitted from the nucleus, 

\(n \rightarrow p+e+\bar \nu\)

During β+ decay, a positron and a neutrino are created and emitted from the nucleus,

\(p \rightarrow n + e^+ + \nu\)

β− decay: \(_Z X^A \rightarrow _{Z+1}Y^A +e +\bar \nu\)

β+ decay: \(_Z X^A \rightarrow _{Z-1}Y^A +e^+ + \nu\)

Before the discovery of neutrino or anti-neutrino, Beta decay was assumed to take place by the release of two particles, either proton, and electron or neutron and positron depending upon the type of beta decay. So the expected energy distribution was discrete distribution. But a continuous energy distribution was observed as shown below.   

To explain this continuous energy spectrum, Pauli suggested that the continuum spectra might be due to one more “invisible” light neutral particle (later to be named neutrino and antineutrino) involved in the β-decay.

Explanation:

\({_zX^A} \longrightarrow {_{z-1}Y^A} + {_{1}e^0} + {\nu}\)

In this reaction a positron (₁e⁰) is being emitted along with a neutrino. Hence, this reaction represents a β+ decay  

The correct answer is option (3)