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Mössbauer effect

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Recoilless emission and recoilless absorption of gamma photons is called Mossbauer effect. It provides us a technique for producing and studying gamma rays whose energies are extremely well defined. Mossbauer effect was discovered by Rudolf Mossbauer in 1958. This effect is applied in the experimental field by the name Mossbauer spectroscopy. Let us first understand why a  nuclear transitions  occurs. After a radioactive nucleus undergoes decay (alpha decay, beta decay, k-capture) it many times reaches to the daughter nuclei state but contains too much energy to be in a final stable state. Unlike our electrons orbiting the nucleus, the nucleus itself doesn’t really have such orbits which are easy to visualize. So, let us just imagine it having a particular quantized energy. Now, to be in a stable ground state it must lose this extra energy. It does this by emitting gamma radiation of that energy. This is the process of nuclear transition, where the nucleus transitions from one
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CZTI detects a gamma ray burst!!

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CZTI was very lucky as on its first day Swift satellite had detected a gamma ray burst(GRB) named GRB 151006A. The scientists at ISRO were eager to know whether CZTI was operational at that time(i.e., outside SAA) & if the GRB was in a favourable condition to be observed. The calculation by the scientists at ISRO showed that the burst was detected 60.7° away from the direction where CZTI was presently pointing at. At this angle CZTI is sensitive to GRBs at energies greater than about 60 keV. The group of young scientists at ISRO delved into the sea of vast data to extract the precious information from GRB 151006A. (Statistics available here .)  We have the Swift and the Fermi satellites observing lots of GRBs, so what if CZTI detects one more?  The Swift satellite, as the name says, is swift at pointing a GRBs but is unable to observe those above 150 keV and fix its spectral parameter for GRBs with hard spectrum. On the other hand, Fermi satellite is sensitive to high energy e
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