f Don Lincoln, Fermilab f Recreating the Universe 3,000,000 Times a Second Don Lincoln Fermilab f

f Don Lincoln, Fermilab f Hubble Telescope This image is taken of galaxies that are billions of light-years away. Light takes a very long time to travel to Earth. Consequently, this photograph is of the conditions that existed billions of years ago, just a billion years or so after the big bang. Astronomers have thus created a time machine of sorts.

f Don Lincoln, Fermilab f

Familiar Cosmology 1In the beginning God created the heaven and the earth. 2And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.

f Don Lincoln, Fermilab f Modern Cosmology Approximately 15 billion years ago, all of the matter in the universe was concentrated at a single point A cataclysmic explosion (of biblical proportions perhaps?) called the Big Bang caused the matter to fly apart. In the intervening years, the universe has been expanding, cooling as it goes.

f Don Lincoln, Fermilab f Big Bang Theory White Sox Version

f Don Lincoln, Fermilab f Consequences of the Big Bang If the universe did come into existence through a cataclysmic explosion, there should be some evidence. Three forms which I will discuss are: –The universe should be expanding –The universe should have a measurable temperature. –The mix of the elements should be known.

f Don Lincoln, Fermilab f Doppler Effect The Doppler effect says that things moving away from you look redder than they would if they weren’t moving. Things moving towards you look more blue. YouSource

f Don Lincoln, Fermilab f Edwin Hubble Using the Doppler effect, Edwin Hubble discovered that objects that were further away move away faster (and, hence, were redder) than nearer objects. This discovery showed that the universe was expanding and still provides one of the best measurements of the age of the universe Galaxies Modern Supernova

f Don Lincoln, Fermilab f Black Body Radiator Universe A black body radiator is one which absorbs all light which is incident on it. Such a body can also emit light, if sufficiently hot. Since the universe is the remnant of a hot explosion, it should thus have a temperature and an ‘afterglow’. ? ? ? ?

f Don Lincoln, Fermilab f Afterglow From the Big Bang

f Don Lincoln, Fermilab f Afterglow From the Big Bang In 1964, while working at Bell Labs, Penzias and Wilson discovered a radio hiss that they couldn’t make go away. They had (by accident!) discovered the remnant ‘echo’ of the Big Bang The universe was shown to have a temperature of 2.726K (-450 °F)

f Don Lincoln, Fermilab f COsmic Background Explorer In 1992, COBE announced a measurement that showed that the background radiation was not quite uniform (although nearly so) This measurement records information approximately 300,000 years after the Big Bang

f Don Lincoln, Fermilab f Goldilocks Effect These three plots show three different effects, each 10% less than the one larger than it. You can see how seeing a small effect first requires removing the bigger one. Full, 10%, and 1% 10% and 1% 1% Full only 10% only

f Don Lincoln, Fermilab f COBE 0 K4 K2.724 K2.732 K K K K K Gross Temperature Profile Motion Dipole Galactic Plane COBE Results

f Don Lincoln, Fermilab f Helium Abundance in the Universe At the late time (as we shall see) of 3 minutes in the history of the universe, atomic nuclei were created. Big Bang theory predicts that the relative abundances of hydrogen and helium were: –Hydrogen 76% –Helium 24% –Lithium 1 part per Due to nuclear fusion in stars since the Big Bang, current abundances: –Hydrogen 73% –Helium 26% –Everything else 1%

f Don Lincoln, Fermilab f Summary of Cosmologic Measurements The Big Bang theory is consistent with observations. Specifically –Hubble Telescope can view the universe ~1,000,000,000 years after the Big Bang –The COBE satellite can view the universe ~300,000 years after the Big Bang –The Hydrogen/Helium ratio can view the universe ~3 minutes after the Big Bang To which a particle physicist replies….

f Don Lincoln, Fermilab f That’s cute……

f Don Lincoln, Fermilab f No….really…..it’s cute……

f Don Lincoln, Fermilab f What’s so interesting about that? All the interesting stuff is over by three minutes. The universe was in a retirement home by then.

f Don Lincoln, Fermilab f The really interesting question is: What happened when the universe was young and hot?

f Don Lincoln, Fermilab f What’s the Point? High Energy Particle Physics is a study of the smallest pieces of matter. It investigates (among other things) the nature of the universe immediately after the Big Bang. It also explores physics at temperatures not common for the past 15 billion years (or so). It’s a lot of fun.

f Don Lincoln, Fermilab f Periodic Table All atoms are made of protons, neutrons and electrons HeliumNeon u d u u d d Proton Neutron Electron Gluons hold quarks together Photons hold atoms together

f Don Lincoln, Fermilab f

Now (15 billion years) Stars form (1 billion years) Atoms form (300,000 years) Nuclei form (180 seconds) Protons and neutrons form ( seconds) Quarks differentiate ( seconds?) ??? (Before that) Fermilab 4× seconds LHC Seconds

f Don Lincoln, Fermilab f The Big Question How do you get something as hot as it was during the Big Bang? Smash stuff together!! Hot!

f Don Lincoln, Fermilab f Fermi National Accelerator Laboratory The highest energy particle accelerator in the world.

f Don Lincoln, Fermilab f Fermi National Accelerator Laboratory (a.k.a. Fermilab) Begun in 1968 First beam 1972 (200, then 400 GeV) Upgrade 1983 (900 GeV) Upgrade 2001 (950 GeV) Jargon alert: 1 Giga Electron Volt (GeV) is 100,000 times more energy than the particle beam in your TV. If you made a beam the hard way, it would take 1,000,000,000 batteries

f Don Lincoln, Fermilab f

How Do You Detect Collisions? Use one of two large multi-purpose particle detectors at Fermilab (DØ and CDF). They’re designed to record collisions of protons colliding with antiprotons at nearly the speed of light. They’re basically cameras. They let us look back in time.

f Don Lincoln, Fermilab f DØ Detector: Run II Weighs 5000 tons Can inspect 3,000,000 collisions/second Will record 50 collisions/second Records approximately 10,000,000 bytes/second Will record (1,000,000,000,000,000) bytes in the next run (1 PetaByte). 30’ 50’

f Don Lincoln, Fermilab f

Remarkable Photos This collision is the most violent ever recorded. It required that particles hit within m or 1/10,000 the size of a proton In this collision, a top and anti-top quark were created, helping establish their existence

f Don Lincoln, Fermilab f Highlights from Run Limits set on the maximum size of quarks (it’s gotta be smaller than 1/1000 the size of a proton) Supported evidence that Standard Model works rather well (didn’t see anything too weird) Studied quark scattering, b quarks, W bosons Top quark discovery 1995

f Don Lincoln, Fermilab f The Needle in the Haystack: Run I There are 2,000,000,000,000,000 possible collisions per second. There are 300,000 actual collisions per second, each of them scanned. We write 4 per second to tape. For each top quark making collision, there are 10,000,000,000 other types of collisions. Even though we are very picky about the collisions we record, we have 65,000,000 on tape. Only 500 are top quark events. We’ve identified 50 top quark events and expect 50 more which look like top, but aren’t. Run II ×10

f Don Lincoln, Fermilab f What Do Top Quarks Look Like? Top quarks are the heaviest particle known. Each one has the mass of an entire gold atom (while remaining among the smallest objects known).

f Don Lincoln, Fermilab f Increasing ‘Violence’ of Collision Expected Number of Events Run II Run I Increased reach for discovery physics at highest masses Huge statistics for precision physics at low mass scales Formerly rare processes become high statistics processes  The Main Injector upgrade was completed in  The new accelerator increases the number of possible collisions per second by  DØ and CDF have undertaken massive upgrades to utilize the increased collision rate.  Run II began March 2001

f Don Lincoln, Fermilab f Run II: What are we going to find? I don’t know! Improve top quark mass and measure decay modes. Do Run I more accurately Supersymmetry, Higgs, Technicolor, particles smaller than quarks, something unexpected?

f Don Lincoln, Fermilab f In 1964, Peter Higgs postulated a physics mechanism which gives all particles their mass. This mechanism is a field which permeates the universe. If this postulate is correct, then one of the signatures is a particle (called the Higgs Particle). Fermilab’s Leon Lederman co-authored a book on the subject called The God Particle. top bottom Undiscovered!

f Don Lincoln, Fermilab f “LEP observes significant Higgs candidates for a mass of 115 GeV with a statistical significance of 2.7  and compatible with the expected rate and distribution of search channels.” Chris Tully, Fermilab Colloquium 13-Dec-2000 Non-Expert Translation: Maybe we see something, maybe we don’t. What we see is consistent with being a Higgs Particle. But it could end up being nothing. It’s Fermilab’s turn.

f Don Lincoln, Fermilab f Data-Model Comparison

f Don Lincoln, Fermilab f Data-Model Comparison

f Don Lincoln, Fermilab f At Fermilab, we collide elementary particles at unprecedented energies, routinely recreating the conditions fractions of a second after the Big Bang. In the spring of 2001, we have resumed operations after a five year upgrade. We will push our understanding of the universe even further back in time. It’s gonna be cool!

f Don Lincoln, Fermilab f “The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found it!), but ‘That's funny...’ ” -- Isaac Asimov

f Don Lincoln, Fermilab f E = m c 2 Energy is Matter Matter is Energy Lots of energy makes lots of matter and vice versa!!!!!!