Speaker is Kirsten Tollefson, associate professor
in the MSU Department of Physics and Astronomy
and a Collider Detector at Fermilab (CDF)
team co-leader: What we’re trying to find
is something that’s very rare, so we’re
expecting one of these single top quarks in
about 20 billion collisions of protons and
anti-protons at this giant particle accelerator
in Chicago. So there’s first of all only
one place in the world that can make these
top quarks and we have two experiments that
live across the ring, this accelerator ring,
from each other and partly we’re doing cross-checks
of each other. [Aerial photo of Fermilab accelerator,
then video of Fermilab particle detector installation.]
We work on the same kinds of physics processes
but we use slightly different technologies
and it’s independent scientists on each
one. So we use similar techniques to look
at similar types of physics processes, but
with completely independent cross-checks,
different sets of data and different manpower.
So this is one way, when we are looking for
something that’s one in 20 billion, you
can make sure you have actually found what
you thought you were looking for.
MSU is unique in that its one of the few universities
in the world that’s on both these two experiments
and in fact is the only university that has
colleagues or professors that were working
on searching for the single top on both the
experiments. So, myself and Dr. Schwienhorst
have been working on this for three or four
years.
Speaker is Reinhard Schwienhorst, assistant
professor in the MSU Department of Physics
and Astronomy and DZero research team co-leader:
This all happens at Fermilab in principle,
but for us it’s not just a lot of resources
that we need in terms of working with people
and having different people all contributing,
but it’s also resources on the intellectual
side -- working with Professor Yuan from Michigan
State who guided us in how exactly we should
analyze the data and exactly what we should
look for. [Graphics of two single top quart
events: the DCF team’s particle collision
event display, then the DZero team’s graphic
of a proton-antiproton collision.] And also
using computing resources, the computer cluster
we have here at Michigan State, which we use
both to prepare samples for this analysis
and to also do the final analysis, but really
also running on computer clusters all over
the world.
[Photo of an MSU-built component of the Large
Hadron Collider at CERN in Switzerland.] Several
of us here at Michigan State are actually
involved in doing the follow-up analysis of
exactly this single top search at the LHC
at CERN, so we’re looking forward to not
just understanding what it is, but really
going beyond it and understanding top quarks
at a much, much deeper level at the LHC.
Speaker is Chien-Peng Yuan, professor in the
MSU Department of Physics and Astronomy and
a particle physics theorist: We are all familiar
with the Einstein equation E=MC2, and we know
about C – the speed of light -- and people
know about Special Relativity, and also that
we know about the energy. However we really
don’t know about the mass -- M. And the
whole object of the electroweak symmetry breaking
has to do with the understanding of this mass.
Where does this mass come from? [Fermilab
animation illustrating 3-D view of aftermath
of particle collisions.]
And the reason that the top quark is so heavy,
as heavy as what we call the vacuum expectation
value, which has the deep connection to the
mass generation, is still unknown and that’s
a very important question. Once we know about
that, then we could then go back to understand
the whole evolution of the universe that’s
described today by the Standard Model, and
plus some additional things such as dark matter
we have not yet found.
Speaker is Jorge Benitez, doctoral candidate
in the MSU Department of Physics and Astronomy
and a key researcher on the DZero team: Being
involved with a discovery is something unique
that doesn’t happen to every grad student,
so I’m very excited that I was involved
with this project, and I’m happy that everything
came out the way it did.
