Elementary Particles Presented

marlon

Standard Model : SU(3)xSU(2)xU(1) gauge theory
Gauge bosons : 8 SU(3) color-coupled gluons, 3 SU(2) 2 W\'s and 1 Z-boson, 1 U(1) B the foton

In the unbroken SU(2)xU(1) gauge theory of the electroweak interactions, there are four fields. These fields are usually called W1, W2, W3, (from SU(2)) and B (from U(1))

After spontaneous symmetry breaking due to the Higgs mechanism, you still have four fields, but three of them gain masses. The W1 and W2 mix to form the W+ and W- and the W3 mixes with the B to form the Z0. The rest of the W3-B mix remains massless and is the photon (often called A and belonging to the remnant U(1) symmetry of QED).


Three generations of spinor fermions divided into:
1) colored doublet left-quarks (ups and downs)
2) doublet left-leptons (electrons and neutrinos)
3) colored right-ups
4) colored right-downs
5) right-electrons
with various hypercharges

The singlet states correspond to particles that don't feel the weak force like 3,4 and 5...

Or you can classify like this :

Mass Particles

---A. Six quarks
------1. Up, down, strange, charm, top, bottom
------2. Combine to form Hadrons in two varieties: baryons, mesons

---B. Six leptons
------1. Three with charge (Tau, muon, electron)
------2. Three neutrinos each corresponding to a charged lepton
------3. Decay, don't combine

II. Three types of interactions mediated by force particles

---A. Strong (gluons)
---B. Electroweak
------1. Electromagnetic (photon)
------2. Weak (Z, W+, W- bosons)
---C. Gravity (graviton?)

Can you understand "the why" of this classification ?
marlon

arivero

No.

I can not understand why the leptons are classified according electric charge, but the quarks are not.

Meir Achuz

The quarks are classified like the leptons.
The quarks come in 3 doublets. (u,d),(c,s),(t,b).
In each doublet the upper quark has a charge +e more than the lower quark.
This is just like the leptons. Details are related to the groups involved.
The group structure is S(3)XSU(2)XU(1).
Why the quarks are +2/3 and -1/3 is involved with hypercharge and group details.
If the GUT is SU(5), the breakdown into this structure is unique,
but th proton decays.

marlon

Here is a nice introductory story on the Top Quark, presented by Fermilab

http://www-ed.fnal.gov/samplers/hsph...ent/index.html

Also check out my TOP QUARK entry in my journal :
http://www.physicsforums.com/journal...90&action=view

regards
marlon

marlon

Let's start the elementary particle journey

http://particleadventure.org/particleadventure/

regards
marlon

Astronuc

Some useful information regarding particles.

Fermions

Fermi-Dirac Statistics

Pauli Exclusion Principle

Bosons

Bose-Einstein Statistics

Spin

Quantum Electrodynamics (QED)

Quantum Chromodynamics (QCD)

Quantum field theory (QFT)

Astronuc

This is a cool website if your into Particle Physics - which I am among many other things - but I have to get up to speed on QCD, QFT, GUT and other things.

Stanford Linear Accelerator Center Virtual Visitor Center

Also -

High Energy Cosmic Rays

Electron Gamma Shower

Have fun!

Hey, Marlon - you were looking for physics opportunities in California. Well - here is one, but it is a bit of drive down to Hollywood!

Astronuc

Some short articles on particle physics from American Institute of Physics - Physics News - http://newton.ex.ac.uk/aip/catagorie...e_physics.html

Astronuc

I search for this but I didn't find it in this thread.

Summary Tables
in the 2002 Review of Particle Physics

http://pdg.lbl.gov/2002/contents_tables.html

Astronuc

News from the particle physics world -

http://www.interactions.org/cms/

marlon

Check THIS SITE if you wanna find out more on the concept of asymptotic freedom in QCD. You need to click on "Nobel Lectures" to read what the 2004 Nobel Laureates in Physics have to say on it.

PS : Did you guys know that the guy in the middle actually played in a movie with Paul Newman ?

regards
marlon

marlon

If you wanna have a very introductory lesson in renormalization theory of the weak interaction, just read the Nobel Lecture of Gerardus 't Hooft, the 1999 Physics Nobel Prize Laureate.

Enjoy


regards
marlon

Astronuc

Deutsche Physikalische Gesellschaft e.V.
http://www.dpg-physik.de/

http://www.dpg-tagungen.de/index.html - auf Deutsch

http://www.dpg-tagungen.de/index_en.html - English

ein Beispiel / example -

http://www.dpg-tagungen.de/archive/2...koeln_prog.pdf

Astronuc

WS 05/06 No. 6811
Ian C. Brock

http://www-zeus.physik.uni-bonn.de/~...ng/vtp_ws0506/

Astronuc

This is really cool!

http://geant4.cern.ch/G4UsersDocumen...nceManual.html

Astronuc

Researchers report the first direct observation of the strange b baryon Xi_b^{-} or [tex]\Xi_b^{-} [/tex]

http://www.arxiv.org/abs/0706.1690

[itex]p\bar{p}[/itex] collisions at [itex]\sqrt{s}[/itex] = 1.96 TeV.

For more publications related to the D0 experiment.
http://www.arxiv.org/find/hep-ex/1/a.../0/1/0/all/0/1

humanino

Hi everyone,

I was earlier today searching for online video material for students who asked me where to find it. I admit that such lectures are much more pleasant to follow than textbooks, although I myself never find the need for video material. The best would be to actually be able to attend the lecture interactively. In any case, it did not occur to me at first, but CERN as an amazing server full of countless presentations on all sorts of topics. Soome of them of incredible value.

You will find them by browsing their web server. Enjoy

Praising thanks to this wonderful initiative.