Enrico Fermi
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Enrico Fermi (1901-1954)

1901 Enrico Fermi was born at Roma, on the 29th of September as son of Alberto Fermi and Ida Gattis. His father was a clerk and the mother was a teacher. He had a brother, Giulio, and a sister, Maria. His brother was extremely smart and even if he was just one year older, he exerted a strong influence on Enrico, fact that early matured him. Since 10-12 years old they were interested in mathematical problems that were over curriculum.  Both were also keen on miniature mechanical constructions.

1913 During this year death separated the two brothers as Giulio could not bear anaesthesia for a neck surgery. Losing his best friend, Enrico tried to banish sadness in books.

One day, while he was coming back home in the evening, he went as usual to pick his father up from the office. Here he met engineer A. Amidei who was amazed by his knowledge and power of scientific thinking. This engineer started to be concerned to Enrico conducting his lectures, borrowing books and later directing him towards physicist career.

1919 Being 17 years old, Enrico Fermi began his life as a student in Pisa, the city of great Galileo. University was easy for this smart young man who already knew mostly of taught subjects.

1922 After four years Enrico got Ph. D. in Physics with “magna cum laudae”. He was 21 years old. This year he also presented, within Academy, three communications regarding relativity, which were published in a German specialist magazine. During next years, Fermi published many theoretical Physics articles showing his orientation of Physics.

He had not reached 25 years old when a new Department of Theoretical Physics was established for him at University in Roma.

1926-1938 During this period, while he worked as a teacher at Rome, Fermi was conducting a rich and fruitful scientific activity, being rightly considered the creator of modern Physics Italian School. Franco Rasetti, Emilio Segre and Eduardo Amaldi were his collaborators in Italy.

Leading this team, Enrico Fermi made extensive theoretical and experimental researches related to quantum Electronics whose evolution led to creation of devices known nowadays like maser, laser; these started to spread in all technique branches having results unrivalled by other achievements. Fermi’s works regarding nuclear Physics are remarkable. Resuming Joliot-Curie’s experiments but using beryllium bombarded with α particles as source of neutrons he succeeded to obtain many radioactive isotopes.

An important discovery is that related to slow neutrons. This is due to a happenstance: neutron irradiated silver became more radioactive (it gets a more intense activity) if the incident neutron flux crossed firstly a lead wall (5 cm thickness) than if it would not have met any obstacle. So, a screen increased the effectiveness of a neutron flux instead of decreasing it.

Fermi replaced heavy atoms screen by one of light elements using a paraffin screen, then a water one. Bombarded silver’s reactivity became very intensive, almost unbelievable. Fermi had understood the strange behaviour of neutrons: the screen slowed the neutrons because of their crush with the substance’s atoms, and the reduced speed of them facilitate their penetration into silver nuclei, so, contrary to expectations, they became more effective. Neutrons slowdown and by this their growth to penetrate into nuclei represented a great achievement of nuclear Physics, achievement that would have a decisive role for voltaic batteries. But the most curious result is that related to uranium bombarding with slowly or slowed neutrons. Initially it was thought that two transuranic elements were obtained: 93 and 94 elements. Then it was proved that this result was unreasonably.

1938 Because of the mentioned results, Fermi was given Nobel Award for Physics.

1939 Fermi emigrated from fascist Italy to USA, where he was appointed teacher at Columbia University, then at Chicago. Here he led the performing of some extensive theoretical and experimental researches which led to great discoveries of nuclear Physics.

1942 On December, Fermi succeeded to start the first self-sustaining chain reaction, so making the first step to controlled release of nuclear energy. He also built the first nuclear reactor. He started the first reaction of High Energy Physics that had remarkable results approaching mesons study, middle-weight particles and especially “exchange forces” study in order to clarify nuclear forces nature.

1954 The summer of this year was the last of Fermi’s life. Doctors discovered a generalized cancer of digestive system that could not be operated. Fermi found out with serenity the tragic news. On the 29th of November he passed away.

In homage for him the element with 100 as nuclear number was called “fermium”. So, the name of this great nuclear expert will be forever written within elements classification table.[1]

 

 

Bibliography:

    1. Enrico Fermi (1901-1954), ro.biography.name