Antimatter (e+, Ps, H-bar) physics Laboratory

Lea Di NotoDepartment of Physics –University of Trento

INFN

Research group

Roberto S. BrusaS. Mariazzi ( assegnista cof. INFN)L. Di Noto (PhD)L. Penasa (tecnico l)M. Bettonte (tecnico nl)

Giancarlo Nebbia (INFN)

G. Ferrari (CNR)

e+ - Ps

detectors

laser

AEgIS (antimatter experiment :gravity interferometry

spectroscopy)apple

earth earth

anti-apple

g g ?

Goals:• Measurement of g on anti-hydrogen• Anti-hydrogen spectroscopy

Methods:– Produce an Hbar beam– Moirè deflectometer

Motivations:• verify the Weak equivalence principle (WEP) • Verify the CPT

antimatter disappearance

p

5 T - 4K trap

MoirèDeflectometer

Positron source

Positron accumulator

Transfer line

1 T - 100 mK Anti-hydrogen

production

AD S

IDE

4/31

activities of Trento group

1 3 2

e+ beam Ps spectroscopy Ps cooling & converter

AEgIS experiment in short

Antiprotons 100 mK

2 ns bunch 108 positronis (1 mm in diameter)

Positron-cooled positronium converter

Moirèdeflectometer

Anti hydrogen beam Stark acceleration

Lasers for Ps excitation in Rydberg states

a

gT

a

dx 2

1. Pulsed positron beam

2. Positronium cooling & converter

Ps

Positronium converter

Positron beam

Ps

Ps

Vacuum

Ps

Ps

0 5 10 15 20 25 30

10

100

b)

Ps

tem

pera

ture

[K]

Side a [nm]

0,0

2,0x103

4,0x103

6,0x103

8,0x103

a)

222

33

2

a

n

mkE

kT m

BB

Mariazzi S, Salemi A and Brusa R S 2008 Phys. Rev. B 78 085428

2 channeltrons

target position

5 NaI scintillators

Trento TOF ApparatusBEAMPrompt peak 16 ns

zo

Mariazzi S, Salemi A and Brusa R S 2008 Phys. Rev. B 78 085428

Ps cooling – first result of Ps cooling

Mariazzi , Bettotti, Brusa, 2010 Phys. Rev. Lett. 104 243401

0.0 0.1 0.2 0.3

T=1515±15K

T=305±10K

T=1425±25K

T=195±10K

T=1260±15K

T=145±10K

7 KeV, T = 300 K 7 KeV, T = 200 K 7 KeV, T = 150 K

log(

dN/d

E) [a

rbitr

ary

units

]

o-Ps kinetic energy [eV]

Permanence time of Ps in nano-channels before escaping into vacuum

<tm> = <tp> + <tf>

tf

tp

z0

Ps energy spectra

tp = 18 ns

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

with the TOF apparatus at the intense positron source

NEPOMUC at the FRMII reactor

p

5 T - 4K trap

MoirèDeflectometer

Positron source

Positron accumulator

Transfer line

1 T - 100 mK Anti-hydrogen

production

AD S

IDE

12/31

3Ps spectroscopy

3. Ps spectroscopy

Our simulation to transport positron bunch from accumulator to the target with duration of 5 ns and a spot of 3 mm diameter !

Buncher

Magnetic field terminator

Valve

sample Detector ports

Three tilted flange

3 Tilted CF16 Flange 45°

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

n=3

continuum

n=1

6.05 eV205 nm

high n~0.75 eV~1650 nm

Planned experiments with Ps chamber

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

Summary

Preventivo 2013

• Missioni interne 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€

-8 k€ per 5 switch -12 k€ per gruppo pompaggio (Turbo, scroll, ionica) -2 k€ per valvola