Amnon Marinov (; 1930 – 2011) was an Israeli physicist. He undertook research into

nuclear structure Understanding the structure of the atomic nucleus is one of the central challenges in nuclear physics. Models The cluster model The cluster model describes the nucleus as a molecule-like collection of proton-neutron groups (e.g., alpha particl ...

nuclear reactions In nuclear physics and nuclear chemistry, a nuclear reaction is a process in which two nuclei, or a nucleus and an external subatomic particle, collide to produce one or more new nuclides. Thus, a nuclear reaction must cause a transformation o ...

, superheavy elements and long-lived

nuclear isomer A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excited state levels (higher energy levels). "Metastable" describes nuclei whose excited states have Half-life, half-lives of ...

Claimed discovery of unbibium

On April 24, 2008, a group led by Marinov at

Hebrew University of Jerusalem The Hebrew University of Jerusalem (HUJI; ) is an Israeli public university, public research university based in Jerusalem. Co-founded by Albert Einstein and Chaim Weizmann in July 1918, the public university officially opened on 1 April 1925. ...

claimed to have found single atoms of

unbibium Unbibium, also known as element 122 or eka-thorium, is a hypothetical chemical element; it has placeholder symbol Ubb and atomic number 122. ''Unbibium'' and ''Ubb'' are the temporary Systematic element name, systematic IUPAC name and symbol resp ...

-292 in natural

thorium Thorium is a chemical element; it has symbol Th and atomic number 90. Thorium is a weakly radioactive light silver metal which tarnishes olive grey when it is exposed to air, forming thorium dioxide; it is moderately soft, malleable, and ha ...

deposits at an abundance of 10⁻¹¹ to 10⁻¹² relative to thorium. This was the first time in sixty-nine years that a new element had been claimed to be discovered in nature, after

Marguerite Perey Marguerite Catherine Perey (19 October 1909 – 13 May 1975) was a French physicist and a student of Marie Curie. In 1939, Perey discovered the element francium by purifying samples of lanthanum that contained actinium. In 1962, she was the fi ...

's 1939 discovery of

francium Francium is a chemical element; it has symbol Fr and atomic number 87. It is extremely radioactive; its most stable isotope, francium-223 (originally called '' actinium K'' after the natural decay chain in which it appears), has a half-l ...

. The claim of Marinov ''et al.'' was criticized by a part of the scientific community, and Marinov said he submitted the article to the journals ''

Nature Nature is an inherent character or constitution, particularly of the Ecosphere (planetary), ecosphere or the universe as a whole. In this general sense nature refers to the Scientific law, laws, elements and phenomenon, phenomena of the physic ...

'' and ''

Nature Physics ''Nature Physics'' is a monthly peer-reviewed scientific journal published by Nature Portfolio. It was first published in October 2005 (volume 1, issue 1). The chief editor is David Abergel. Scope ''Nature Physics'' publishes both pure and appli ...

'' but both turned it down without sending it for peer review. The unbibium-292 atoms were claimed to be

superdeformed In nuclear physics a superdeformed nucleus is a nucleus that is very far from spherical, forming an ellipsoid with axes in ratios of approximately 2:1:1. Normal deformation is approximately 1.3:1:1. Only some nuclei can exist in superdeformed state ...

or hyperdeformed

s, with a half-life of at least 10⁸ years. A criticism of the technique, previously used in purportedly identifying lighter

isotopes by

mass spectrometry Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used ...

, was published in ''

Physical Review C Physical may refer to: *Physical examination In a physical examination, medical examination, clinical examination, or medical checkup, a medical practitioner examines a patient for any possible medical signs or symptoms of a Disease, medical co ...

'' in 2008. A rebuttal by the Marinov group was published in ''Physical Review C'' after the published comment. A repeat of the thorium experiment using the superior method of

accelerator mass spectrometry Accelerator mass spectrometry (AMS) is a form of mass spectrometry that accelerates ions to extraordinarily high kinetic energies before mass analysis. The special strength of AMS among the different methods of mass spectrometry is its ability t ...

(AMS) failed to confirm the results, despite a 100-fold better sensitivity. This result throws considerable doubt on the results of the Marinov collaboration with regards to their claims of long-lived isotopes of

roentgenium Roentgenium () is a synthetic chemical element; it has symbol Rg and atomic number 111. It is extremely radioactive and can only be created in a laboratory. The most stable known isotope, roentgenium-282, has a half-life of 130 seconds, althoug ...

and unbibium. It is still possible that traces of unbibium might exist in some thorium samples, though given current understanding of superheavy elements, this is very unlikely.

Family

Amnon Marinov lived in

Jerusalem Jerusalem is a city in the Southern Levant, on a plateau in the Judaean Mountains between the Mediterranean Sea, Mediterranean and the Dead Sea. It is one of the List of oldest continuously inhabited cities, oldest cities in the world, and ...

, Israel with his wife Rachel; they have four children and six grandchildren. His father, Haim Marinov (1904–2001), was the deputy mayor of

from 1964 until 1973. His father-in-law, Ya'akov Maimon (1902–1977), was the inventor of Hebrew

stenography Shorthand is an abbreviated symbolic writing method that increases speed and brevity of writing as compared to longhand, a more common method of writing a language. The process of writing in shorthand is called stenography, from the Greek ''s ...

and received the

Israel Prize The Israel Prize (; ''pras israél'') is an award bestowed by the State of Israel, and regarded as the state's highest cultural honor. History Prior to the Israel Prize, the most significant award in the arts was the Dizengoff Prize and in Israel ...

in 1976 for his lifelong voluntary work teaching Hebrew to new immigrants all over the country. Amnon Marinov died on December 7, 2011.

Notes

References

External links

Marinov's site, including a full list of his publications

{{DEFAULTSORT:Marinov, Amnon 1930 births 2011 deaths Israeli nuclear physicists Jewish physicists Thorium Scientists from Jerusalem Academic staff of the Hebrew University of Jerusalem Israeli Jews Israeli people of Russian-Jewish descent