Merritt Moore Physics 95, 2009 T R A P P E D ANTIPARTICLES

Why do we want trapped antiparticles?

- Storing antiprotons and positrons - Antihydrogen - Reason why Overview

1) Slow down 2) Capture 3) Cool down 4) Accumulate 1) Storing antiparticles 2) Antihydrogen 3) Reason why Storing Antiprotons

1) Slow Down ✤ Ejected from Antiproton Decelerator of CERN ✤ Passed through beryllium degrader 1) Storing antiparticles 2) Antihydrogen 3) Reason why bunches of 3 × 10 7 antiprotons every 100 sec 0.1% pass through energy ~ 5MeV energy ~ 3 keV

2) Capture ✤ Use a Penning Trap ✤ 3 electrodes (ring and two endcaps) ✤ Axial magnetic field ✤ Quadrupole electric field ω c = qB/m 1) Storing antiparticles 2) Antihydrogen 3) Reason why

3) Cool down 1) Storing antiparticles 2) Antihydrogen 3) Reason why low energy ✤ Antiprotons oscillate and collide with electrons and low temperature

4) Accumulate ✤ More the merrier! ✤ repeat slow 2. capture 3. cool 4. accumulate 1) Storing antiparticles 2) Antihydrogen 3) Reason why ✤ Final Temperature = 4 kelvin (~269 C) ✤ Reduce energy by 10,000,000,000!!

Storing Positrons ✤ From radioactive source ✤ Slowed- in gas ✤ Captured- in separate Penning trap ✤ Led by B field lines to Penning trap 1) Storing antiparticles 2) Antihydrogen 3) Reason why where antiprotons will join

Antihydrogen ✤ Positrons cool antiprotons ✤ Interact to form antihydrogen 1) Storing antiparticles 2) Antihydrogen 3) Reason why

Antihydrogen ✤ BUT antihydrogen = zero charge 1) Storing antiparticles 2) Antihydrogen 3) Reason why ✤ can’t stay in penning trap -> hit walls and annihilate ✤ New apparatus with magnetic trap that can store antihydrogen ✤ Get even more accurate results ✤ Next step:

Reason Why ✤ CPT Invariance Theorem ✤ Proton = Antiproton ✤ Matter = AntiMatter ✤ Fundamental test of basic physics 1) Storing antiparticles 2) Antihydrogen 3) Reason Why ✤ Hydrogen = Antihydrogen

Reason Why ✤ Thing 1 = Thing 2 ?