Diapositiva 1

Antimatter (e+, Ps, H-bar)
physics Laboratory
Lea Di Noto
Department of Physics –University of Trento
INFN
Research group
Roberto S. Brusa
S. Mariazzi ( assegnista cof. INFN)
L. Di Noto (PhD)
L. Penasa
(tecnico l)
M. Bettonte (tecnico nl)
e+ - Ps
Giancarlo Nebbia (INFN)
detectors
G. Ferrari (CNR)
laser
AEgIS
(antimatter experiment :gravity interferometry
spectroscopy)
Goals:
apple
• Measurement of g on anti-hydrogen
• Anti-hydrogen spectroscopy
Methods:
g
earth
– Produce an Hbar beam
– Moirè deflectometer
antimatter disappearance
Motivations:
• verify the Weak equivalence principle (WEP)
• Verify the CPT
anti-apple
g?
earth
activities of Trento group
AD SIDE
Positron
source
e+ beam
Ps spectroscopy
Ps cooling & converter
1
3
2
Positron
accumulator
Transfer line
5 T - 4K
trap
p
1 T - 100 mK
Anti-hydrogen
production
Moirè
/31
4
Deflectometer
AEgIS experiment in short
2 ns bunch 108
positronis (1 mm
in diameter)
Positron-cooled positronium
converter
Lasers for Ps excitation in
Rydberg states
Antiprotons 100 mK
dx gT 2

a
a
Anti hydrogen beam
Stark acceleration
Moirè
deflectometer
1. Pulsed positron beam
2. Positronium cooling & converter
Ps temperature [K]
Positron beam
Ps
Ps
8,0x10
3
6,0x10
3
4,0x10
3
2,0x10
3
a)
0,0
b)
100
10
Ps
0
5
10
15
20
25
30
Side a [nm]
Ps
2
 2 2  n m 
T
E


3k B
3k B m  a 
Ps
Vacuum
Positronium
converter
Mariazzi S, Salemi A and Brusa R S 2008 Phys. Rev. B 78 085428
2
BEAM
Trento TOF Apparatus
Prompt peak 16 ns
2 channeltrons
target position
5 NaI scintillators
zo
Ps cooling – first result of Ps cooling
Mariazzi S, Salemi A and Brusa R S
2008 Phys. Rev. B 78 085428
Mariazzi , Bettotti, Brusa,
2010 Phys. Rev. Lett. 104 243401
log(dN/dE) [arbitrary units]
7 KeV, T = 300 K
7 KeV, T = 200 K
7 KeV, T = 150 K
T=305±10K
T=1515±15K
T=195±10K
T=1425±25K
T=145±10K
T=1260±15K
0.0
0.1
0.2
0.3
o-Ps kinetic energy [eV]
Permanence time of Ps in nano-channels before
escaping into vacuum
Ps energy spectra
z0
tf
tp
<tm> = <tp> + <tf>
tp = 18 ns
with the TOF apparatus
at the intense positron source
NEPOMUC at the FRMII reactor
Tunable nanochannels will allow to study:
 Cooling and thermalization at temperature < 150 K
 Cooling and thermalization in presence of decorated surfaces
 Relations between diffusion and tortuosity
3. Ps spectroscopy
3
AD SIDE
Ps spectroscopy
Positron
source
Positron
accumulator
Transfer line
5 T - 4K
trap
p
1 T - 100 mK
Anti-hydrogen
production
/31
12
Moirè
Deflectometer
sample
Detector ports
Magnetic field terminator
Buncher
Valve
Our simulation to transport positron bunch from accumulator to the target with duration of 5
ns and a spot of 3 mm diameter !
3 Tilted
CF16 Flange
45°
Three tilted flange
Planned experiments with Ps
chamber
FIRST GOAL:
• Study of production efficiency of Ps in Rydberg state
OTHER GOAL:
• Rydberg state in presence of magnetic field
• Motional stark effect
• Ps laser cooling
• Jump between different levels (microwave)
METHOD:
• Ps production and detection by PbF2 scintillator
• Excitation up to n=3
• Excitation from n=3 to n>15
continuum
high n
~0.75 eV
~1650 nm
n=3
6.05 eV
205 nm
n=1
Summary
Our work is about:
• Running AEgIS positron bunched beam
• Ps production in AEgIS
• Foundamental studies on Ps cooling
(TOF at FRMII-Munich)
• Development of a new apparatus for Ps
spectroscopy measurements
Preventivo 2013
 3 k€
• Missioni estere
 22 k€ + 8 k€ (sub
iudice)
•Materiale di consumo  4 k€ per materiale da
vuoto
•Impianti attrezzature  0
•Altre immobilizzazioni  22 k€
• Missioni interne
-8 k€ per 5 switch
-12 k€ per gruppo pompaggio
(Turbo, scroll, ionica)
-2 k€ per valvola