Discovery of new element 117 tennessine in pictures
Actinide target materials from ORNL’s High Flux Isotope Reactor (HFIR) and Radiochemical Engineering Development Center (REDC) were essential for many superheavy element discoveries. Here an REDC chemical operator Tim Raley performs the delicate chemical separation of 249Bk from HFIR-irradiated Am/Cm material to prepare target material for the element 117 campaign.
Chemists at ORNL’s Radiological Engineering Development Center (REDC) performing work on the chemical separation and purification of 249Bk. C. E. Porter and Frank Riley (left) obtained the first 22-mg sample used for irradiations with an intense 48Ca beam at the Joint Institute for Nuclear Reactions in Dubna, Russia, to produce the first atoms of element 117. Shelley VanCleve and Rose Boll (right) are shown working on the second batch of 249Bk that was split between the Dubna and Darmstadt laboratories for experiments confirming the discovery (Dubna and Darmstadt) and for the search for new element 119 (Darmstadt). The highly purified 249Bk material is available only from ORNL in quantities sufficient for the synthesis of new elements.
The green dot at the end of the glass tube is 22 milligrams of ultrapure 249Bk separated at the ORNL’s REDC from forty grams of HFIR-irradiated Am/Cm in spring 2009 for the element 117 campaign.
Vladislav Shchegolev, a physicist from the Joint Institute for Nuclear Research at Dubna (Russia), carefully removes a can containing 249Bk from a shielded shipping container at Sheremetyevo Airport in Moscow. The container was opened at the request of customs authorities in order to verify the contents before accepting the shipment from ORNL.
The element 117 discovery was featured on the cover of Physical Review Letters, vol. 104, no. 14 (2010), the issue containing the discovery paper. The illustration depicts the observed alpha decay chains from the 293117 and 294117 isotopes of element 117 produced using 249Bk+48Ca reaction. Eleven new superheavy isotopes were identified in these decay chains.
Alpha-decay half-lives of superheavy isotopes with odd atomic numbers Z=107 to Z=117 as a function of emitter neutron number. The vertical dashed lines at neutron numbers N=152 and at N=162 indicate the deformed shell closures that are associated with increased nuclear stability. The half-lives of new isotopes measured during the experiments with 249Bk target and 48Ca beam (red symbols) indicate increased stability with increasing neutron number, providing experimental verification for the existence of the predicted island of enhanced stability for superheavy nuclei.
Oak Ridge High School science teacher, Dr. Nivedita Ganguly, adds new element 117 to the Periodic Table of Elements, April 2010.
Images of ORNL nuclear physicist Krzysztof Rykaczewski and ORNL Wigner Fellow Krzysztof Miernik in the Physics Division reflected at the surfaces of Silicon detectors of a new detection system for superheavy nuclei. This new charge-particle detection array included eight custom designed Si-detectors with the largest Double-sided Silicon Strip Detector ever produced. Together with a digital data acquisition system, the new detectors were commissioned at ORNL and later installed for superheavy element experiments at JINR.
Nathan Brewer and Krzysztof Rykaczewski at the Flerov Laboratory for Nuclear Reactions of JINR Dubna during fine tuning of the ORNL-provided digital data acquisition system.
Jim Roberto and Krzysztof Rykaczewski holding a Periodic Table updated with new elements Nh, Mc, Ts and Og during the celebration at ORNL, January 2017. The copies of this Periodic Table, signed by the Tennessee Governor Bill Haslam and ORNL director Thom Mason, were donated by UT-Battelle to all public middle and high schools in Tennessee.
Academician Yuri Oganessian of JINR Dubna and scientific leader of the international collaboration presented a Wigner lecture at the ORNL celebration for the discovery of element 117 in January 2017. Following the lecture, Prof. Oganessian spoke with Tennessee Governor Bill Haslam about the discovery and the naming of tennesssine. Also pictured left to right are Tim Hallman, director of the DOE’s Office of Nuclear Physics; Sergey Dmitriev, director of the Flerov Laboratory of Nuclear Reactors at JINR; JINR director Victor Matveev; and ORNL director Thom Mason.
ORNL’s Jim Roberto and Krzysztof Rykaczewski present Yuri Oganessian with a commemorative bottle of Jack Daniel’s single barrel select “Element 117Ts” whiskey at a celebration of the discovery new elements 115 moscovium, 117 tennessine, and 118 oganesson in Dubna, Russia in March 2017.
ORNL’s Jim Roberto and Krzysztof Rykaczewski and UTK’s Robert Grzywacz were invited to the office of Tennessee Lieutenant Governor Randy McNally (center standing) on the occasion of a Special Resolution of the Tennessee House and Senate recognizing the discovery of element 117 and naming it “tennessine”, March 2017.
The United Nations General Assembly during its 74th Plenary Meeting proclaimed 2019 as the International Year of the Periodic Table of Chemical Elements (IYPT 2019) in December 2017. The IYPT2019 was adopted by the General Conference of UNESCO (United Nations Educational, Scientific, and Cultural Organization). The proclamation commemorated the 150th anniversary of Dmitri Mendeleyev’s discovery of the periodic system. The year 2019 also marked the 100-year anniversary of the International Union of Pure and Applied Chemistry (IUPAC).
IUPAC with help from the International Younger Chemists Network (IYCN) created a Periodic Table of Younger Chemists, from hundreds of international nominations, see https://iupac.org/100/pt-of-chemist/, to honor promising young scientists as the faces of the chemical elements. The honorees for the 6 heaviest elements, from Z=113 to Z=118, were unveiled during a special ceremony at the IUPAC General Assembly Meeting in Paris, France in July 2019.
Unveiling the face of element 117 tennessine during the IUPAC General Assembly meeting in Paris, July 2019. Promising young scientists were chosen by IUPAC for each of the 118 elements of the Periodic Table. Nathan T. Brewer of the ORNL Physics Division and the UT-ORNL Joint Institute for Nuclear Physics and Applications was selected to represent new element 117 tennessine for his work on the heaviest elements, including Z=118 Oganesson.
Clarice Phelps of Oak Ridge National Laboratory, here standing in front of a hot cell at the ORNL’s Radiochemical Engineering Development Center, was recognized for her work on heavy actinides separation including 249Bk used in the element 117 synthesis as a face for Z=99 einsteinium at the Periodic Table of Younger Chemists.
New element discoveries were featured in the hit TV comedy “The Big Bang Theory”.
Amy in the Big Bang Theory, Season 9 Episode 15: “The Valentino Submergence.” Note the element 117 decay chain in the background.