Horia Hulubei (; 15 November 1896 – 22 November 1972) was a

Romania Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, S ...

nuclear physicist Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter. Nuclear physics should not be confused with atomic physics, which studies the ...

, known for his contributions to the development of

X-ray spectroscopy X-ray spectroscopy is a general term for several spectroscopic techniques for characterization of materials by using x-ray radiation. Characteristic X-ray spectroscopy When an electron from the inner shell of an atom is excited by the energy o ...

Education and military service

Born in

Iași Iași ( , , ; also known by other alternative names), also referred to mostly historically as Jassy ( , ), is the second largest city in Romania and the seat of Iași County. Located in the historical region of Moldavia, it has traditionally ...

, he graduated in 1915 first in his class at the Boarding High School of Iași. He then enrolled in the Faculty of Sciences at the

University of Iași The Alexandru Ioan Cuza University (Romanian: ''Universitatea „Alexandru Ioan Cuza"''; acronym: UAIC) is a public university located in Iași, Romania. Founded by an 1860 decree of Prince Alexandru Ioan Cuza, under whom the former Academia Mih ...

, but his studies were interrupted by the entry of Romania in

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...

; conscripted into the army, he fought as a second lieutenant at the battles of Nămoloasa, Băltăreți, and

Mărășești Mărășești () is a small town in Vrancea County, Western Moldavia, Romania. It administers six villages: Călimănești, Haret, Modruzeni, Pădureni, Siretu and Tișița. Geography The town is located in the eastern part of the county, on th ...

in the summer of 1917. General

Henri Mathias Berthelot Henri Mathias Berthelot (7 December 1861 – 29 January 1931) was a French general during World War I. He held an important staff position under Joseph Joffre, the French commander-in-chief, at the First Battle of the Marne, before later command ...

, the head of the French military mission to Romania, decided to send a group of young Romanians (including Hulubei) to France to train at an aviation school; upon completing the training, Hulubei participated as a pilot on a

fighter aircraft Fighter aircraft are fixed-wing military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air superiority of the battlespace. Domination of the airspace above a battlefield ...

of the

French Air Service The French Air and Space Force (AAE) (french: Armée de l'air et de l'espace, ) is the air and space force of the French Armed Forces. It was the first military aviation force in history, formed in 1909 as the , a service arm of the French Arm ...

on the

Western Front Western Front or West Front may refer to: Military frontiers * Western Front (World War I), a military frontier to the west of Germany *Western Front (World War II), a military frontier to the west of Germany *Western Front (Russian Empire), a maj ...

. Gravely wounded, he was awarded the

Legion of Honour The National Order of the Legion of Honour (french: Ordre national de la Légion d'honneur), formerly the Royal Order of the Legion of Honour ('), is the highest French order of merit, both military and civil. Established in 1802 by Napoleo ...

. Upon returning to Romania, he worked for a while in civil aviation, and helped start the first Romanian air service, connecting

Istanbul ) , postal_code_type = Postal code , postal_code = 34000 to 34990 , area_code = +90 212 (European side) +90 216 (Asian side) , registration_plate = 34 , blank_name_sec2 = GeoTLD , blank_i ...

to Bucharest to

Budapest Budapest (, ; ) is the capital and most populous city of Hungary. It is the ninth-largest city in the European Union by population within city limits and the second-largest city on the Danube river; the city has an estimated population o ...

. In 1922 he returned to his studies in physics and chemistry, completing in 1926 his undergraduate degree at the University of Iași, ''

magna cum laude Latin honors are a system of Latin phrases used in some colleges and universities to indicate the level of distinction with which an academic degree has been earned. The system is primarily used in the United States. It is also used in some Sou ...

''. He then went to

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. Si ...

for his graduate studies, obtaining his Ph.D. from

Paris-Sorbonne University Paris-Sorbonne University (also known as Paris IV; french: Université Paris-Sorbonne, Paris IV) was a public research university in Paris, France, active from 1971 to 2017. It was the main inheritor of the Faculty of Humanities of the Universit ...

, where his advisor was the

Nobel laureate The Nobel Prizes ( sv, Nobelpriset, no, Nobelprisen) are awarded annually by the Royal Swedish Academy of Sciences, the Swedish Academy, the Karolinska Institutet, and the Norwegian Nobel Committee to individuals and organizations who make o ...

Jean Perrin Jean Baptiste Perrin (30 September 1870 – 17 April 1942) was a French physicist who, in his studies of the Brownian motion of minute particles suspended in liquids (sedimentation equilibrium), verified Albert Einstein’s explanation of this p ...

. His Ph.D. thesis with the title ''"Contribution to the study of quantum diffusion of X-rays"'' was defended in 1933 in Paris in front of an examination committee chaired by Nobel laureate

Marie Curie Marie Salomea Skłodowska–Curie ( , , ; born Maria Salomea Skłodowska, ; 7 November 1867 – 4 July 1934) was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity. She was the fir ...

. Afterwards he continued his research at the

University of Paris , image_name = Coat of arms of the University of Paris.svg , image_size = 150px , caption = Coat of Arms , latin_name = Universitas magistrorum et scholarium Parisiensis , motto = ''Hic et ubique terrarum'' (Latin) , mottoeng = Here and a ...

, staying in contact with the likes of

Frédéric Joliot-Curie Jean Frédéric Joliot-Curie (; ; 19 March 1900 – 14 August 1958) was a French physicist and husband of Irène Joliot-Curie, with whom he was jointly awarded the Nobel Prize in Chemistry in 1935 for their discovery of Induced radioactivity. T ...

Paul Langevin Paul Langevin (; ; 23 January 1872 – 19 December 1946) was a French physicist who developed Langevin dynamics and the Langevin equation. He was one of the founders of the ''Comité de vigilance des intellectuels antifascistes'', an ant ...

, and

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theor ...

Scientific achievements

Between 1927 and 1938, he worked alternately in Paris and at the University of Iași, where he established the first laboratory of the structure of matter in Romania. With the help of his advanced X-ray spectroscopy equipment he observed several previously unidentified X-ray spectral lines, and subsequently came to the decision that such lines are associated with new elements. In 1936, Hulubei together with Yvette Cauchois claimed to have discovered element 85 via X-ray analysis, conducting further research and publishing on follow-up studies in 1939. With Cauchois and Sonia Cotelle, he established the presence of

polonium Polonium is a chemical element with the symbol Po and atomic number 84. Polonium is a chalcogen. A rare and highly radioactive metal with no stable isotopes, polonium is chemically similar to selenium and tellurium, though its metallic character ...

and

neptunium Neptunium is a chemical element with the symbol Np and atomic number 93. A radioactive actinide metal, neptunium is the first transuranic element. Its position in the periodic table just after uranium, named after the planet Uranus, led to it bein ...

. Hulubei also claimed and published the discovery of a new element, "moldavium", in 1936, the discovery of "sequanium" in 1939, and that of "dor" in 1945. Later, however, it was shown that the reported X-ray lines did not belong to new elements. Hulubei's samples for "dor" did contain the real element 85 (

astatine Astatine is a chemical element with the symbol At and atomic number 85. It is the rarest naturally occurring element in the Earth's crust, occurring only as the decay product of various heavier elements. All of astatine's isotopes are short-live ...

), but his means to detect it were too weak, by current standards, to enable correct identification; moreover, he could not perform chemical tests on the element. For his many scientific achievements the National Institute for Physics and Nuclear Engineering in Romania was named after him, as the "Horia Hulubei National Institute of Physics and Nuclear Engineering" (IFIN HH). He was the Founder and First Director of the (IFA) in Măgurele in 1949. Elected corresponding member of the

Romanian Academy The Romanian Academy ( ro, Academia Română ) is a cultural forum founded in Bucharest, Romania, in 1866. It covers the scientific, artistic and literary domains. The academy has 181 active members who are elected for life. According to its byl ...

in 1937, Hulubei became a titular member in 1946. Stripped of membership by the new

communist regime A communist state, also known as a Marxist–Leninist state, is a one-party state that is administered and governed by a communist party guided by Marxism–Leninism. Marxism–Leninism was the state ideology of the Soviet Union, the Cominte ...

in 1948, he was restored to the Academy in 1955. Hulubei was also corresponding member (from 1935) and titular member (from 1941) of the Romanian Academy of Sciences, and served as Vice-President of the organization in 1947–48.

University teaching

During the early 1960s and 1970s Hulubei was a Professor of Atomic Physics in the Department of Atomic and Nuclear Physics of the Faculty of Physics at the

University of Bucharest The University of Bucharest ( ro, Universitatea din București), commonly known after its abbreviation UB in Romania, is a public university founded in its current form on by a decree of Prince Alexandru Ioan Cuza to convert the former Princel ...

, where he delivered elegant and clear lectures on the

Compton effect Compton scattering, discovered by Arthur Holly Compton, is the scattering of a high frequency photon after an interaction with a charged particle, usually an electron. If it results in a decrease in energy (increase in wavelength) of the photon ...

and inelastic Compton scattering/ resonant inelastic X-ray scattering (RIXS).

Publications

* ''Course Notes of Physical Chemistry'', Ed. Academiei, Bucharest, 1940. ( "Curs de chimie fizică "(1940)) * ''X-ray Spectroscopy'' ("Spectroscopia X"). (1948) * ''The Structure of Matter.'' "Structura materiei" (1950)

References

External links

Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HHLibrary of Congress
{{DEFAULTSORT:Hulubei, Horia 1896 births 1972 deaths Alexandru Ioan Cuza University alumni University of Paris alumni Romanian nuclear physicists Rectors of the University of Bucharest Titular members of the Romanian Academy Members of the Romanian Academy of Sciences Fellows of the American Physical Society Academic staff of the University of Bucharest Romanian military personnel of World War I Romanian aviators World War I pilots Recipients of the Legion of Honour Academic staff of Alexandru Ioan Cuza University