so element 117 officially joined the periodic table in 2016 the name
periodic table in 2016 the name
periodic table in 2016 the name Tennessee n– was chosen to reflect the
Tennessee n– was chosen to reflect the
Tennessee n– was chosen to reflect the contributions of the tennessee region to
contributions of the tennessee region to
contributions of the tennessee region to the discovery the ending i and ii is
the discovery the ending i and ii is
the discovery the ending i and ii is characteristic of column 17 elements
characteristic of column 17 elements
characteristic of column 17 elements like chlorine fluorine and now tennessee
like chlorine fluorine and now tennessee
like chlorine fluorine and now tennessee n– in fact you would have thought
n– in fact you would have thought
n– in fact you would have thought perhaps that the name would have been
perhaps that the name would have been
perhaps that the name would have been tennessee ‘m that’s what we what we what
tennessee ‘m that’s what we what we what
tennessee ‘m that’s what we what we what we’re used to in terms of new elements
we’re used to in terms of new elements
we’re used to in terms of new elements but the chemist told us oh no group 17
but the chemist told us oh no group 17
but the chemist told us oh no group 17 this has to end in irony the result
this has to end in irony the result
this has to end in irony the result could not have been achieved without
could not have been achieved without
could not have been achieved without international collaboration and this
international collaboration and this
international collaboration and this required unique facilities both in
required unique facilities both in
required unique facilities both in Russia and in the United States it also
Russia and in the United States it also
Russia and in the United States it also required a team of physicists chemists
required a team of physicists chemists
required a team of physicists chemists and engineers more than 100 in both
and engineers more than 100 in both
and engineers more than 100 in both countries adding a new element to the
countries adding a new element to the
countries adding a new element to the periodic table is very exciting and also
periodic table is very exciting and also
periodic table is very exciting and also a significant scientific accomplishment
a significant scientific accomplishment
a significant scientific accomplishment but the element 117 discovery was much
but the element 117 discovery was much
but the element 117 discovery was much more than that it also advanced the
more than that it also advanced the
more than that it also advanced the understanding of nuclei with extreme
understanding of nuclei with extreme
understanding of nuclei with extreme numbers of protons and neutrons
numbers of protons and neutrons
numbers of protons and neutrons including the decay products from
including the decay products from
including the decay products from element 1 117 11 new loop new nuclei
element 1 117 11 new loop new nuclei
element 1 117 11 new loop new nuclei were added to the nuclear chart and it
were added to the nuclear chart and it
were added to the nuclear chart and it also forced that foreshadows the
also forced that foreshadows the
also forced that foreshadows the discovery of even heavier elements
element 117 is a so-called super-heavy
element 117 is a so-called super-heavy element this term is refers to elements
element this term is refers to elements
element this term is refers to elements with more than 103 protons with Seaborg
with more than 103 protons with Seaborg
with more than 103 protons with Seaborg who predicted the existence of
who predicted the existence of
who predicted the existence of super-heavy elements in the 1960s and he
super-heavy elements in the 1960s and he
super-heavy elements in the 1960s and he realized that new facilities would be
realized that new facilities would be
realized that new facilities would be required for heavy element chemistry and
required for heavy element chemistry and
required for heavy element chemistry and so he proposed the development of a high
so he proposed the development of a high
so he proposed the development of a high flux reactor and radio chemical
flux reactor and radio chemical
flux reactor and radio chemical processing center at Oak Ridge National
processing center at Oak Ridge National
processing center at Oak Ridge National Laboratory to advance this research and
Laboratory to advance this research and
Laboratory to advance this research and his vision turns out to have been very
his vision turns out to have been very
his vision turns out to have been very important for this discovery which comes
important for this discovery which comes
important for this discovery which comes more than 50 years later Seberg also
more than 50 years later Seberg also
more than 50 years later Seberg also predicted the existence of an island of
predicted the existence of an island of
predicted the existence of an island of stability for super-heavy elements you
stability for super-heavy elements you
stability for super-heavy elements you may recall from high school chemistry
may recall from high school chemistry
may recall from high school chemistry that atoms with closed shells of
that atoms with closed shells of
that atoms with closed shells of electrons are more stable think than
electrons are more stable think than
electrons are more stable think than think the noble gases well it turns out
think the noble gases well it turns out
think the noble gases well it turns out that nuclei have shells of protons and
that nuclei have shells of protons and
that nuclei have shells of protons and and neutrons and those nuclei with
and neutrons and those nuclei with
and neutrons and those nuclei with closed shells of protons and and
closed shells of protons and and
closed shells of protons and and neutrons have stronger binding the last
neutrons have stronger binding the last
neutrons have stronger binding the last stable isotope led 2:08 has a closed
stable isotope led 2:08 has a closed
stable isotope led 2:08 has a closed shell for both neutrons and protons well
shell for both neutrons and protons well
shell for both neutrons and protons well we can imagine we can calculate where
we can imagine we can calculate where
we can imagine we can calculate where the next closed shells would be can we
the next closed shells would be can we
the next closed shells would be can we get there and if we could get there what
get there and if we could get there what
get there and if we could get there what would the lifetimes be some theories
would the lifetimes be some theories
would the lifetimes be some theories predict that the lifetime would be
predict that the lifetime would be
predict that the lifetime would be millions of years that’s very exciting
millions of years that’s very exciting
millions of years that’s very exciting so we are on a journey not only to
so we are on a journey not only to
so we are on a journey not only to discover new elements but also define
discover new elements but also define
discover new elements but also define long-lived elements beyond the known
long-lived elements beyond the known
long-lived elements beyond the known periodic table at the island of
periodic table at the island of
periodic table at the island of stability so what are the key questions
stability so what are the key questions
stability so what are the key questions the key questions are where does the
the key questions are where does the
the key questions are where does the periodic table end we don’t know what is
periodic table end we don’t know what is
periodic table end we don’t know what is the limit of the number of protons and
the limit of the number of protons and
the limit of the number of protons and neutrons a nucleus can contain
neutrons a nucleus can contain
neutrons a nucleus can contain we don’t know do super-heavy elements
we don’t know do super-heavy elements
we don’t know do super-heavy elements have special nuclear properties and
have special nuclear properties and
have special nuclear properties and special chemical properties we expect so
special chemical properties we expect so
special chemical properties we expect so and does the predicted island of
and does the predicted island of
and does the predicted island of stability exist and one of the important
stability exist and one of the important
stability exist and one of the important results of this work is a very strong
results of this work is a very strong
results of this work is a very strong indication that it does so how do you
indication that it does so how do you
indication that it does so how do you make a super-heavy element well you can
make a super-heavy element well you can
make a super-heavy element well you can do it around your kitchen table all you
do it around your kitchen table all you
do it around your kitchen table all you need to do is find a combination of two
need to do is find a combination of two
need to do is find a combination of two atoms that when you combine their
atoms that when you combine their
atoms that when you combine their protons they add to the number of
protons they add to the number of
protons they add to the number of protons you want in your new element and
protons you want in your new element and
protons you want in your new element and then you smash these two atoms together
then you smash these two atoms together
then you smash these two atoms together in a high-energy accelerator and for for
in a high-energy accelerator and for for
in a high-energy accelerator and for for element 117 an intense beam of a special
element 117 an intense beam of a special
element 117 an intense beam of a special isotope of calcium what is directed at a
isotope of calcium what is directed at a
isotope of calcium what is directed at a berkland target now Burke Liam is an
berkland target now Burke Liam is an
berkland target now Burke Liam is an artificial element has to be made
artificial element has to be made
artificial element has to be made artificially at an energy of around 250
artificially at an energy of around 250
artificially at an energy of around 250 MeV now if you look at the at the
MeV now if you look at the at the
MeV now if you look at the at the representation at the bottom of the
representation at the bottom of the
representation at the bottom of the slide we’re starting with a calcium 48
slide we’re starting with a calcium 48
slide we’re starting with a calcium 48 nucleus which has 20 protons we’re
nucleus which has 20 protons we’re
nucleus which has 20 protons we’re impacting it on a Brooklyn 249 nucleus
impacting it on a Brooklyn 249 nucleus
impacting it on a Brooklyn 249 nucleus which has 97 protons and 20 plus 97
which has 97 protons and 20 plus 97
which has 97 protons and 20 plus 97 equals 117 so on rare occasions these
equals 117 so on rare occasions these
equals 117 so on rare occasions these fuse they create a compound nucleus in a
fuse they create a compound nucleus in a
fuse they create a compound nucleus in a very excited state and the trick is for
very excited state and the trick is for
very excited state and the trick is for that compound nucleus to survive long
that compound nucleus to survive long
that compound nucleus to survive long enough that you can discover the new
enough that you can discover the new
enough that you can discover the new elements so in in our case the choice of
elements so in in our case the choice of
elements so in in our case the choice of the calcium 48 in Berkeley in 249 was
the calcium 48 in Berkeley in 249 was
the calcium 48 in Berkeley in 249 was key because these both have very large
key because these both have very large
key because these both have very large excesses in number of neutrons so that
excesses in number of neutrons so that
excesses in number of neutrons so that compound nucleus has many extra neutrons
compound nucleus has many extra neutrons
compound nucleus has many extra neutrons before it can fly apart it sheds energy
before it can fly apart it sheds energy
before it can fly apart it sheds energy by shedding those extra neutrons and
by shedding those extra neutrons and
by shedding those extra neutrons and that’s why element 117 exists
that’s why element 117 exists
that’s why element 117 exists so what did it take to produce a few
so what did it take to produce a few
so what did it take to produce a few atoms of element 117 well you remember
atoms of element 117 well you remember
atoms of element 117 well you remember the calcium 48 it it is a naturally
the calcium 48 it it is a naturally
the calcium 48 it it is a naturally occurring isotope of calcium but it’s
occurring isotope of calcium but it’s
occurring isotope of calcium but it’s very rare so it has to be enriched by
very rare so it has to be enriched by
very rare so it has to be enriched by 500 times then you need to produce 20
500 times then you need to produce 20
500 times then you need to produce 20 milligrams of Burk Liam to 249 an
milligrams of Burk Liam to 249 an
milligrams of Burk Liam to 249 an element that does not exist in nature
element that does not exist in nature
element that does not exist in nature this was produced by Neutron irradiation
this was produced by Neutron irradiation
this was produced by Neutron irradiation over almost a year in the world’s
over almost a year in the world’s
over almost a year in the world’s highest thermal Neutron flux at Oak
highest thermal Neutron flux at Oak
highest thermal Neutron flux at Oak Ridge National Laboratory this is
Ridge National Laboratory this is
Ridge National Laboratory this is followed by a very delicate chemical
followed by a very delicate chemical
followed by a very delicate chemical separation because what comes out out of
separation because what comes out out of
separation because what comes out out of the reactor has lots of stuff in it and
the reactor has lots of stuff in it and
the reactor has lots of stuff in it and it’s very radioactive this chemical
it’s very radioactive this chemical
it’s very radioactive this chemical separation has to be done behind three
separation has to be done behind three
separation has to be done behind three feet of concrete it takes about six
feet of concrete it takes about six
feet of concrete it takes about six weeks and and the final material has to
weeks and and the final material has to
weeks and and the final material has to be purified to one part in ten to the
be purified to one part in ten to the
be purified to one part in ten to the seven then you have to produce targets
seven then you have to produce targets
seven then you have to produce targets that can survive heavy ion beam
that can survive heavy ion beam
that can survive heavy ion beam irradiation and then you actually array
irradiation and then you actually array
irradiation and then you actually array v8 those targets for 150 days in the in
v8 those targets for 150 days in the in
v8 those targets for 150 days in the in the world’s highest in the world’s most
the world’s highest in the world’s most
the world’s highest in the world’s most intense calcium 48 beam which is
intense calcium 48 beam which is
intense calcium 48 beam which is available at the floor off laboratory in
available at the floor off laboratory in
available at the floor off laboratory in termina Russia major the major
termina Russia major the major
termina Russia major the major facilities at Oak Ridge and Dubner were
facilities at Oak Ridge and Dubner were
facilities at Oak Ridge and Dubner were essential to this experiment and the
essential to this experiment and the
essential to this experiment and the what’s what’s pictured here is the heavy
what’s what’s pictured here is the heavy
what’s what’s pictured here is the heavy ion cyclotron at Dubna and the reactor
ion cyclotron at Dubna and the reactor
ion cyclotron at Dubna and the reactor chemical separation complex at all grids
chemical separation complex at all grids
chemical separation complex at all grids the same complex that was seaborg’s
the same complex that was seaborg’s
the same complex that was seaborg’s vision more than 100 scientists and
vision more than 100 scientists and
vision more than 100 scientists and engineers contributed to the discovery
engineers contributed to the discovery
engineers contributed to the discovery this includes scientists from Dubna from
this includes scientists from Dubna from
this includes scientists from Dubna from Oak Ridge from Lawrence Livermore
Oak Ridge from Lawrence Livermore
Oak Ridge from Lawrence Livermore National Lab from the University of
National Lab from the University of
National Lab from the University of Tennessee and from Vanderbilt and from
Tennessee and from Vanderbilt and from
Tennessee and from Vanderbilt and from the University of Nevada in addition
the University of Nevada in addition
the University of Nevada in addition more than 100 technical staff
more than 100 technical staff
more than 100 technical staff at Oakridge and a governor were needed
at Oakridge and a governor were needed
at Oakridge and a governor were needed to support the berkeley impression and
to support the berkeley impression and
to support the berkeley impression and the separation and and separation and
the separation and and separation and
the separation and and separation and the accelerator campaign in russia
the accelerator campaign in russia
the accelerator campaign in russia pictured are the the scientists and
pictured are the the scientists and
pictured are the the scientists and engineers who performed the chemical
engineers who performed the chemical
engineers who performed the chemical separation at Oakridge and in the circle
separation at Oakridge and in the circle
separation at Oakridge and in the circle is actually a picture of the 20
is actually a picture of the 20
is actually a picture of the 20 milligrams of berkeley ‘m that was
milligrams of berkeley ‘m that was
milligrams of berkeley ‘m that was produced it’s that little green dot if
produced it’s that little green dot if
produced it’s that little green dot if you can see it at the very bottom of the
you can see it at the very bottom of the
you can see it at the very bottom of the glass vial so six atoms of element 117
glass vial so six atoms of element 117
glass vial so six atoms of element 117 were produced in the first campaign how
were produced in the first campaign how
were produced in the first campaign how did we know we had element 117 well we
did we know we had element 117 well we
did we know we had element 117 well we produce two isotopes of element 1 1 1 1
produce two isotopes of element 1 1 1 1
produce two isotopes of element 1 1 1 1 17 1 with a hundred and seventy-seven
17 1 with a hundred and seventy-seven
17 1 with a hundred and seventy-seven neutrons the other with 176 these
neutrons the other with 176 these
neutrons the other with 176 these isotopes decay into nine additional
isotopes decay into nine additional
isotopes decay into nine additional heaviest isotopes of elements 115-113
heaviest isotopes of elements 115-113
heaviest isotopes of elements 115-113 111 etc by subsequent by sequential
111 etc by subsequent by sequential
111 etc by subsequent by sequential alpha particle II emissions this decays
alpha particle II emissions this decays
alpha particle II emissions this decays chain provides a unique signature for
chain provides a unique signature for
chain provides a unique signature for element 117 the likelihood that that
element 117 the likelihood that that
element 117 the likelihood that that sequence of events could be produced at
sequence of events could be produced at
sequence of events could be produced at random is less than 1 in a million
now we talked earlier about the island
now we talked earlier about the island of stability and as we approach it we
of stability and as we approach it we
of stability and as we approach it we expect the lifetimes to increase so the
expect the lifetimes to increase so the
expect the lifetimes to increase so the element 117 experiment provided an
element 117 experiment provided an
element 117 experiment provided an opportunity for us to test this by
opportunity for us to test this by
opportunity for us to test this by looking at previous data and then in the
looking at previous data and then in the
looking at previous data and then in the and the new data from the decays
and the new data from the decays
and the new data from the decays development 1 1 117 so for a particular
development 1 1 117 so for a particular
development 1 1 117 so for a particular isotope for particularly element element
isotope for particularly element element
isotope for particularly element element 113 we we now have a span of isotopes
113 we we now have a span of isotopes
113 we we now have a span of isotopes spanning 8 neutral Neutron numbers from
spanning 8 neutral Neutron numbers from
spanning 8 neutral Neutron numbers from the
the
the lightest to the heaviest what happens as
lightest to the heaviest what happens as
lightest to the heaviest what happens as we add neutrons to that element 1:13
we add neutrons to that element 1:13
we add neutrons to that element 1:13 isotope well the lifetimes are going out
isotope well the lifetimes are going out
isotope well the lifetimes are going out and over that sequence of eight neutron
and over that sequence of eight neutron
and over that sequence of eight neutron numbers the lifetime actually went up by
numbers the lifetime actually went up by
numbers the lifetime actually went up by a factor of seven thousand you would
a factor of seven thousand you would
a factor of seven thousand you would have expected without an island of
have expected without an island of
have expected without an island of stability for the lifetimes actually to
stability for the lifetimes actually to
stability for the lifetimes actually to be going down and so this is the
be going down and so this is the
be going down and so this is the strongest evidence we have to date of
strongest evidence we have to date of
strongest evidence we have to date of the existence of the island of stability
the data that we got is very consistent
the data that we got is very consistent you can look from these charts at how
you can look from these charts at how
you can look from these charts at how well it it fits the air is outlined in
well it it fits the air is outlined in
well it it fits the air is outlined in blue is the new data added from these
blue is the new data added from these
blue is the new data added from these experiments so it’s a significant
experiments so it’s a significant
experiments so it’s a significant increase in our understanding of the
increase in our understanding of the
increase in our understanding of the nuclear landscape for the heaviest
nuclear landscape for the heaviest
nuclear landscape for the heaviest elements and it also continues the trend
elements and it also continues the trend
elements and it also continues the trend of increased stability for increasing
of increased stability for increasing
of increased stability for increasing Neutron numbers now we got a bonus when
Neutron numbers now we got a bonus when
Neutron numbers now we got a bonus when we discovered an element 117 because we
we discovered an element 117 because we
we discovered an element 117 because we also discovered element 115 which is the
also discovered element 115 which is the
also discovered element 115 which is the decay product of element 1 117 so we got
decay product of element 1 117 so we got
decay product of element 1 117 so we got 2 4 1 and it is very fitting that the
2 4 1 and it is very fitting that the
2 4 1 and it is very fitting that the names chosen for these two elements were
names chosen for these two elements were
names chosen for these two elements were Tennyson in recognition of the
Tennyson in recognition of the
Tennyson in recognition of the contributions of Oak Ridge National Lab
contributions of Oak Ridge National Lab
contributions of Oak Ridge National Lab Vanderbilt and and the University of
Vanderbilt and and the University of
Vanderbilt and and the University of Tennessee and moscovia in recognition of
Tennessee and moscovia in recognition of
Tennessee and moscovia in recognition of the come of the contributions made by
the come of the contributions made by
the come of the contributions made by our collaborators in Russia there were
our collaborators in Russia there were
our collaborators in Russia there were two other elements that were named at
two other elements that were named at
two other elements that were named at the same time okay listen
the same time okay listen
the same time okay listen which is element 118 it is named for
which is element 118 it is named for
which is element 118 it is named for Yuri ogen Sen who is the scientific
Yuri ogen Sen who is the scientific
Yuri ogen Sen who is the scientific leader of the floor off laboratory and
leader of the floor off laboratory and
leader of the floor off laboratory and the key partner in these experiments
the key partner in these experiments
the key partner in these experiments excuse me
and neoneun which was discovered in
and neoneun which was discovered in japan yuri organ essien is one of two
japan yuri organ essien is one of two
japan yuri organ essien is one of two living persons who has ever had an
living persons who has ever had an
living persons who has ever had an element named after him the other beat
element named after him the other beat
element named after him the other beat SeaWorld
SeaWorld
SeaWorld so in summary two new elements with
so in summary two new elements with
so in summary two new elements with atomic numbers 115 and 117 have been
atomic numbers 115 and 117 have been
atomic numbers 115 and 117 have been synthesized they demonstrate increased
synthesized they demonstrate increased
synthesized they demonstrate increased stability with increasing Neutron number
stability with increasing Neutron number
stability with increasing Neutron number longer half-lives will enable single
longer half-lives will enable single
longer half-lives will enable single element chemistry on these new atoms we
element chemistry on these new atoms we
element chemistry on these new atoms we are at the shores of the fabled island
are at the shores of the fabled island
are at the shores of the fabled island of stability and new a new elements up
of stability and new a new elements up
of stability and new a new elements up to element 120 are within our sights the
to element 120 are within our sights the
to element 120 are within our sights the next steps let’s go to higher atomic
next steps let’s go to higher atomic
next steps let’s go to higher atomic numbers let’s go to higher neutron
numbers let’s go to higher neutron
numbers let’s go to higher neutron numbers we are working now on special
numbers we are working now on special
numbers we are working now on special isotopes of element 118 which would be
isotopes of element 118 which would be
isotopes of element 118 which would be the heaviest nuclei ever produced
the heaviest nuclei ever produced
the heaviest nuclei ever produced and we are searching for new elements
and we are searching for new elements
and we are searching for new elements 119 and 120 super-heavy elements are
119 and 120 super-heavy elements are
119 and 120 super-heavy elements are important because they offer the
important because they offer the
important because they offer the potential for new physics new chemistry
potential for new physics new chemistry
potential for new physics new chemistry and new material science using atoms
and new material science using atoms
and new material science using atoms previously unknown that have extreme
previously unknown that have extreme
previously unknown that have extreme numbers of electrons protons and
numbers of electrons protons and
numbers of electrons protons and neutrons element 117 is a very
neutrons element 117 is a very
neutrons element 117 is a very significant step toward that island of
significant step toward that island of
significant step toward that island of stability and the continued progress in
stability and the continued progress in
stability and the continued progress in this area rests on the shoulders of a
this area rests on the shoulders of a
this area rests on the shoulders of a community of scientists and engineers
community of scientists and engineers
community of scientists and engineers who harness the power of international
who harness the power of international
who harness the power of international collaboration thank you and the last is
collaboration thank you and the last is
collaboration thank you and the last is the latest version of the periodic table
the latest version of the periodic table
the latest version of the periodic table thank you
thank you
thank you [Applause]
”
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