david doll. *in one slide the particles represent our current theory of fundamental physics many...
Post on 19-Dec-2015
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*In one slide
The particles represent our current theory of fundamental physicsMany outstanding questions:
“Gravity?”, “Neutrino Mass?”, “Matter vs. Anti Matter?”
My experiment dealt with answering the latter question
Introducing the Elephant – an Overview of Particle Physics*
Our theory does allow for a small amount (~1 Billion times too small) of asymmetry through the decay of heavy particles to light particles.
What can cause the imbalance?
e+ e-Y(4S)
bb
B0
B0
We reconstruct the B mesons (one is matter, the other anti-matter) to look for differences.
All measurements are consistent with our theoryAll except Matter/Anti matter asymmetry of courseThe theorists who gave us this theory won half of the Nobel
prize in physics last year.Where do we go from here?
Many new theories, “Beyond the Standard Model”-theories, try to come up with new sources of matter/anti matter differences
All must reproduce what has already been shownSearches with Babar’s data can already place limits on the
parameters of these new theories (my thesis deals with this)
What we do known’t
We look at a b quark turning into an s quark and emitting a photon.Very sensitive to the effects of New Physics (NP) modelsThe rate is around 1 in 10,000 B mesons decays in a mode
we care about
My Thesis – Quickly!!
An example “Feynman diagram”:
γ “Weak Force”-carriers (from first slide). Could be replaced by new particles in NP theories
Chance to go to Washington D.C. to lobby Congress on behalf of particle physicsOnly graduate student from my experiment (~500
collaborators)
Beyond my Thesis
~1/2 the group (it was 8AM!!)
Involved in the Caltech Grad Student CouncilThis year’s Advocacy Committee chairWorking to increase graduate student exposure to potential
donors as a way of increasing graduate student fellowshipsInvolvement in teaching/tutoring programs
RISE program – Only Math/Science focused tutor program in Pasadena Unified School District
YESS program – targets gifted under-represented minority students in physics and biology.
Life at Caltech