AEgIS - consiglio di sezione - PowerPoint Presentation

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AEgIS- consiglio di sezione Luglio 2017

G. Testera

AEgIS (Antimatter Experiment

gravity

Interferometry Spectroscopy)

Quale fisica?

Verifica accurata della

validita’ di simmetrie sulle quali si fonda la descrizione delle interazioni fondamentali 1) CPT attraverso spettroscopia 2) WEP attraverso misure dirette o spettroscopia

Perche’?a) Verifica di fondamenti b) Ricerca di segnali oltre la fisica standard (CPT violation- Lorentz Violation con o senza possibili violazioni di WEP ) Complementare rispetto ad altri settori

6 Esperimenti al CERN incluso AEgIS su Antiproton Decelerator (AD)

Formazione di

Hbar

, temperatura sub Kelvin

Antiprotons from PSDeceleration

+

phase space

compressionHbar

ingredients

AEgISAntiproton Decelerator100-110 secAntiprotons: AD 5 MeV

Positrons: 22Na 0- 0.54

MeV3.5 107

antiprotons

in 200 ns

100 sec rep. rate

5

MeV

kinetic

energy

Trapping

Cooling

(from

MeV

to

tens of meV)Manipulation of very low energy pbar, e+, e-Hbar formation and detectiong measurement (Moire pattern- interferometry)

To be

done

in the

e

xperiment

:

Hbar

formation

How to

make

Hbar? pulsed formation formation time known (

within tens ns) important for g measurement Rydberg

levels range known

beam

formation

with

electric

field

gradients

AEgIS

:

Charge

exchange

with Rydberg PositroniumCross section for Rydberg antihydrogen production via charge exchange between Rydberg Positroniums and antiprotons in a magnetic fieldPhys. Rev. A 94 022714 (2016)D. Krasnicky, R. Caravita, C. Canali, G. Testera

Trap&cool

pbar

Trap&cool

e+

Make

Ps

ExcitePs

via laser

pulses

Make

&

detect

Hbar

Make

the

beam

Measure

g

Antiprotons

from AD

Buffer gas

type

e+ accumulatore+ measurement setup : Magnetic pulsed e+ transfer line5T1TThe AEgIS setup installed

at CERNg measurement Region (not installed

)

Accumulator for e+

Magnetic

transfer line for e+

Superconducting

magnetic

fields

cryogenic

traps

(105

electrodes

)

antiH detector (scintillating cryogenic fibers and SiPm) External (scintillators) and internal (MCP+phosp.; Faraday cups in cryo-UHV ) detectorslasers XUHV 10-13 mb@10K

Antiproton trap

electrodes: C1-C19

Positron trap

el: P1-P14

Transfer sect.

el.: T1-T6HV1HV2

HV3

e-

gun

75 cm

1T

Hbar

Production

region

e

+

Ps

Target for Ps

formation

5 T

Trap

radius

1.25 cm

Trap

radius

0.5 cm

5 T

AEgIS detectors

T-line

“Kicker

pulser

” (or e+ pick-up amplifier)

5TMCP+Phosphor+CCD camera(facing traps)Si Beam counter Central Region FC (Sectors of Au plated Cu facing both sides)1T MCP

+ Phosphor+ CMOS camera(facing 1T traps)Plastic scintillators

(PMT readout: either digitized or counting mode)

Plastic Scintillator

(HPD readout)

FACT

800

scint

fibers

+

SiPm

24

fibers

signal

digitized

RF tuned circuit and 4 KCryoamp (axial e- detection)

Cryoamp 2

(radial pbar det)

T-line CsI

Al Faraday

Cup

(

facing

trap

and

e+transf

line)

Cryo

PbF2

(e+)

PbF2 + PMT

readout

(e+)

NE111+ PMT

readout

(e+)

PbF2 + PMT

readout

(e+)

Attivita’ del gruppo di Genova

Cattura, raffreddamento

pbar con plasmi di elettroni Compressione radiale plasmi misti confinatiTrasporto pbar

5T- 1TCooling in1TTrasporto e+ nei magneti principaliE

ccitazione laser Ps

Example: Pbar

cooling

e

-

=4.4 108e->109Cold pbar on 5TMCPResidual not

cooled pbar: a) 35% with about 4.4 108 e- b) 3% with > some 10

9 e- MCP+Phosph+CCD

We

routinely

trap

3.5 10

5

pbar@9KV

Fast (

tens

ns 9 KV

pulse

-

developed

in Genoa)

Cooling with e- @5T to few tens KCompression via RF of mixed e- and pbar plasma(Coll. paper

ready to be

submitted

, Genoa

resp

.)

Mixed plasma

compression

Pretransfer

&

shift pbar

run 67468

Pretransfer&

no shift pbar run 60402Pbar cloud: about 0.3 mm radius@1T Transport of compressed pbar plasma 5T-1TPbar follow magnetic field linesIssue: small misalignement

between 5T and 1T off center by about 2 mm in the production trap (5 mm radius)Strategy

for pbar trajectory correction

on

flight

developed

@Genoa

EXB

drift

&

balistic

transfer &

recatch

Possible

also

thanks to fast & precise 200 V pulses (developed in Genoa)2 mm

e+ direct injection

e+

Magnetic

pulsed transfer line

5T magnet1T magnet

5T traps1T trapsAEgIS Proposal

catch e+ in flight in the 5T traps manipulate

(cool, RW)

transfer in 1T

traps

manipulate

(cool, RW)+ off

axis

by

diocotron

excitation

acceleration

(some KV)

toward the target

2) Direct e+ injection Send e+ directly, without recatching them , from the accumulator to the 1 T target Accelerate on flight & compress in time pbar

Daniel K.

Not

to scale

On

axis

Off

axis

Attivita’ in corso (run Maggio 2017- Dicembre 2017)

Eccitazione Ps: dimostrata nella regione di test (

AEgIS Coll. Phys

. Rev A (2016))Formazione Ps in 1T: OKEccitazione Ps in 1T: in progress (primi segnali??)

Trasporto pbar nella regione formazione Hbar: OKCooling

pbar in regione formazione Hbar : OKTemperatura @1T : in progress in queste settimaneCommissioning rivelatore Hbar : in progress (no Genova)Formazione Hbar: prossimo goal immediato

Oltre alla presa datiUpgrade della trappola formazione

Hbar

(disegno, costruzione)Test a Genova in L202 (?)

Impegni servizi:Progettazione meccanica 4-6 mesiOfficina meccanica 2-3 mesiOfficina elettronica 2 mesi

G. Testera 70% (resp. Naz.)

D. Krasnicky 100%V. Lagomarsino 100% (ma limiti di eta’..)F. Sorrentino 20% (ma sinergia con nuova attivita’ proposta…)L. Di Noto 30%M. Fani 100%G. Sobrero 100%

g measurement

Counts vs vertical coordinate

L=few tens

cm

Grating

period a : few tens mm

High resolution position detector : few mmShift of the periodic pattern due to vertical

forces (gravity)

Direct

g

measurement

(WEP test)

cold

Hbar

beam

(

few

100 m/s-

subK

energy)moiré deflectometer

expected accuracy: 1% higher precision with ultracold antiprotons and/or large statisticsPhase shift

1% (

stat

.

only

) with 600

detected

vertices

and 2-3 micron

resolution

(

achievable

with

emulsions

+

silicon

detectors)

Pbar transfer, no e-: centering pbar in UC

Balistic

transfer: 5T trap not

aligned to 1 T trap

Pbar

launched from 5 TEXB with electric field in the position of B0 electrodeRecatch in OnAx28-UC15 & dumpSee the plasma center as a function of the B0 voltage