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>>>Michael Fitzgerald: Our next speaker is going to be Andy Lankford. Andy is a particle
physicist at the University of California Irvine and deputy director of ATLAS, which
is one of the four particle detectors at the large hadron collider, the sort of world beating
particle accelerator tool that he's going to now talk to us about the development of.
Andy, welcome. >>Andrew Lankford: So it's a pleasure to be
here today to have the opportunity to tell you about the fun I have at my job. The large
hadron collider is a journey of discovery. It's a global undertaking to solve the mysteries
of nature both at the smallest scales of the quantum world and at the very largest scales
of the cosmos. So I'll introduce you to the LHC. But in the
process, I will try to convey the scientific challenge but also as well the extreme technological
innovation that's needed in order to address these challenges and also what we've reached
in terms of extreme levels of collaboration. Finally, I'll try to illustrate how tacting
the basic questions of science is a catalyst for innovation.
So, in order to imagine the challenge, since we're here at a Google event, consider what
most be the world's most energetic search engine. It's a project sited on the border
between France and Switzerland at CERN, the European laboratory for particle physics.
It's a 17-mile long ring lined with superconducting magnets. It's buried deep underground. It
accelerates two beams of protons at nearly the speed of light. The two beams are brought
into violent collision with energy densities that we haven't -- the universe hasn't experienced
since right after the Big ***. The beams collide in the center of complex arrays of
particle detectors. Deep in the heart of the detectors, protons from each beam interact
and create new particles. These particles are detected by rays of particle detectors,
and data is recorded, tremendous amounts of data, up to 1500 peta-bytes of data per experiment
over its lifetime. And scientists will search this data for answers to the question.
What are the queries that we make? What are the questions that we ask? Some are age-old
questions. How has the universe evolved since its creation, since the Big ***?
What drives the motion of the heavenly bodies of the stars? For instance, like in this image
of merging galaxies? Today we know that the motion is largely driven
by what we call dark matter, matter that isn't visible, not the luminous matter you see here.
The age-old questions include question of what are the basic building blocks of the
universe? We know, of course, that molecules are made of atoms and atoms are made of protons,
neutrons, and electrons. But there are many more types of particles.
Why are there so many types? Well, one of our speakers today explained
that. Murray Gell-Mann explained that all the particle species arrived from three simple
smaller particles, the quarks. But are quarks the end of the story?
Other questions are more recent and relate to the quantum world. Dark matter. What is
the particle nature of dark matter? Anti-matter, why is there more matter than anti-matter?
When was the symmetry broken? Supersymmetry. Is there a supersymmetric partner, a heavy
supersymmetric partner for each of our particles? Extra dimensions. Are there just three spatial
dimensions, or are there more? Our everyday world is the mid-point of 60
powers of 10 stretching from the small universe at the time of the Big *** to the very large
universe of today. Telescopes examine the large universe. The LHC is a super-microscope
to study the subatomic world. What search engine are we using to find the
answers to our questions? What is the science experiment that we've mounted? The world's
most powerful particle accelerator, the LHC, has been built in an underground ring. The
ring is solidly lined with superconducting magnets to guide the protons. Inside the beams,
there are two beam pipes. And within the vacuum of these pipes the beams travel. Energy is
pumped into the ring to accelerate the beams to within one/millionth of the speed of light.
Each beam is composed of protons. The protons collide at four locations around the ring.
Energy turns into matter producing jets of particles -- Some ordinary, some familiar,
possibly some never seen before. These particles are measured by experiments. ALICE; ATLAS,
the experiment that I work on; CMS; and LHCb. The LHC accelerator is a technological tour de force, a collection
of extreme accomplishments. A complex of smaller accelerators prepare the particles for the
LHC. The LHC performs the final stage of acceleration,
accelerating the protons to an energy of 7 trillion energy volts. At this energy, the
protons make 10,000 turns of the ring every second. During the time that a proton spends
in the beam, it travels 10 billion miles, further than going to Neptune and back.
Superconducting magnets are the critical components that make available to us the energy that
we need for our research. The dipole magnets are each about 30 meters long.
Without superconducting magnets, the LHC would be nearly five times as big and consume 40
times as much energy. Magnets are installed end-to-end around the ring and aligned with
incredible precision. The superconducting coils are insulated in cryostats. Each magnet
contains two coils, one for each of the beams. The beam cannot be allowed to escape. It has
enough energy to melt 50 tons of copper. Instrumentation is required to control the beams. Every one
of the 1800 superconducting magnets needs to be operating properly in order to circulate
the beams. There's no redundancy available in this machine.
The magnets are cooled by super fluid liquid helium at a temperature just two degrees above
absolute zero. It's colder than the vacuum in outer space. The liquid helium plant is
probably the largest installation in the world. The beam travels through an intense vacuum.
Inside the vacuum pipe the atmosphere is thinner than it is on the moon. There's 17,000 particle
accelerators in the world today that are used in industry, for medicine, as well as in research
and other fields. The construction of ATLAS was a tremendous engineering undertaking as
well, beginning with the excavation of a cavern to accommodate its monumental size, ATLAS
is half a football field in length. It's about 80 feet tall and 80 feet wide. It has as much
steel as the Eiffel Tower and it's about the size of a cathedral. The 4-year long assembly
the pieces of ATLAS in the cavern was like assembly of a ship in a bottle but, of course,
on a much grander scale. Starting from the undercarriage designed to
precisely position the 7,000-ton weight, an array of racetrack-shaped superconducting
coils was assembled to form a magnetic field that enshrouds the entire detector. This field
bends particles called muons to measure their momentum. Chambers inside the field detect
the muons with a precision much less than the thickness of a hair, even a thin hair.
Other particle detectors are put inside the toroid. The ATLAS toroid is perhaps the iconic
feature defining the ATLAS experiment. Last year it even appeared in Valencia as a set
of Barlioz's opera, "The Trojans." ATLAS was constructed from pieces constructed
around the world. Tracker modules made in the U.S., a superconducting solloid magnet
made in Japan, a tile calorimeter module. These modules were made in Spain, Russia and
the U.S. A cryogenic liquid Argon calorimeter arriving
from Canada. Another was made in Europe. Here's a big wheel made with chambers that
came from China, Israel, Japan and the U.S. And here is the so-called small wheel, the
last component of ATLAS being lowered down 100 meters into the pit.
ATLAS is the fruit of the labor of 6,000 individuals and 20 years of design, construction, and
assembly. Although enormous, ATLAS measures particles
with an incredible precision, a precision that drives challenging technological solutions.
The innermost detectors are like silicone digital cameras. Small precise detectors are
assembled into large precision arrays. These detectors are as intricate as a fly's eye.
These cameras have about 100 million pixels each. Not so impressive by today's standards,
but keep in mind that we take 40 million pictures per second. Particle detectors such as these
are used now quite a bit for medical imaging. The challenge of our search of new discoveries,
the challenge of finding just a handful of interesting particle interactions in the billions
of trillions that we witness, requires vast computational resources and some innovative
new techniques. Large processor farms process data in nearly
real time to sift through tens of thousands of particle interactions per second to pick
just the 100 to 200 interactions that we can afford to store.
Even with this reduction, our detectors are so fine grained that each experiment may store
about 15 petabytes of data each year. This data volume is equivalent to a stack of 15
million CDs, about -- a stack that would go about 12 miles high.
In order to amass, the required computational resources needed to reconstruct and analyze
our data, CERN and the experiments have assembled the worldwide LHC Computing Grid. This is
an association of 60 or so computer centers around the globe. Data is recorded at CERN,
and then it is distributed to the other centers which are organized in clouds of geographical
clusters. Jobs are sent wherever they can find the data
that they need. Grid computing is working quite well for us today.
The technical challenges of the LHC require an extreme level of collaboration. The LHC
accelerator was built and financed by the CERN laboratory. CERN was established by 12
European nations by treaty in 1954, and it is now distinctly the premier particles physics
laboratory in the world. The LHC experiments were built and financed
by large international collaborations of scientists from institutions around the globe with CERN
as a member institution. As an example, ATLAS is a collaboration of 175 institutions from
37 countries. It's truly a global collaboration as you can see from the map.
There are 3,000 scientists, including 1,000 students involved.
Students play a special role in particle physics. They are essential contributors to the science.
They receive excellent scientific and technical training and that training serves them well
in their ultimate careers. ATLAS was designed, collaboratively, built
collaboratively and it is now maintained collaboratively. How can such a collaboration design and manage
a project of this scale? The answer is we are united by our scientific goals.
How can scientists and institutions around the world contribute to a project that's based
in Switzerland? We rely heavily on collaborative tools that enable us to communicate at a distance,
often ineffectively. The need to communicate amongst our extreme collaborations gave birth
to the Worldwide Web at CERN 25 years ago. How far are we in our journey of discovery?
We have reached a milestone like this moment from Ron Howard's Sony Pictures film "Angels
and Demons." >>> Collisions are fixed and running.
>>Andrew Lankford: That's my detector. >>> Particles at 99% the speed of light.
(Video.) >>Andrew Lankford: How far are we in our journey
of discovery? Last November the LHC achieved its first collisions. In December, it reached
a world record collision energy. In March, it reached a collision energy three times
higher than that. In 2012, the energy will be doubled again.
Each of these milestones is a momentous occasion from the experimental teams.
The experiments have since collected enough data to start the exploration of new scientific
territory. Nonetheless, we are just starting the journey. It is likely to take years to
search enough interactions enough to find something that revolutionizes our understanding.
During the coming years, we will advance the frontiers of knowledge beyond our current
understanding, exploring the theories and questions that we have posed and finally reaching
beyond our theories into the unknown, a regime in which we might discover something truly
and excited, something totally unexpected. The search to answer questions never before
answered requires techniques never before used. Basic research catalyzes innovation.
Thank you. [ Applause ]