AEgIS- consiglio di sezione Luglio 2017 G. Testera

AEgIS (Antimatter Experiment gravity Interferometry Spectroscopy) Formazione di Hbar, temperatura sub Kelvin 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)

To be done in the experiment: Hbar ingredients AEgIS Antiprotons: AD 5 MeV Antiproton Decelerator Positrons: 22Na 0- 0.54 MeV AEgIS 100-110 sec 3.5 107 antiprotons in 200 ns 100 sec rep. rate 5 MeV kinetic energy Antiprotons from PS Deceleration+ phase space compression Trapping Cooling (from MeV to tens of meV) Manipulation of very low energy pbar, e+, e- Hbar formation and detection g measurement (Moire pattern- interferometry) To be done in the experiment:

AEgIS: Charge exchange with Rydberg Positronium Hbar formation How to make Hbar? AEgIS: Charge exchange with Rydberg Positronium pulsed formation formation time known (within tens ns) important for g measurement Rydberg levels range known beam formation with electric field gradients Trap&cool pbar Trap&cool e+ Make Ps ExcitePs via laser pulses Make & detect Hbar Make the beam Measure g Cross section for Rydberg antihydrogen production via charge exchange between Rydberg Positroniums and antiprotons in a magnetic field Phys. Rev. A 94 022714 (2016) D. Krasnicky, R. Caravita, C. Canali, G. Testera

Buffer gas type e+ accumulator The AEgIS setup installed at CERN e+ measurement setup : g measurement Region (not installed) Buffer gas type e+ accumulator Magnetic pulsed e+ transfer line 5T 1T Antiprotons from AD 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 ) detectors lasers XUHV 10-13 mb@10K

5 T e+ Ps 5 T e- gun 75 cm 1T el: P1-P14 el.: T1-T6 Positron trap Antiproton trap electrodes: C1-C19 Positron trap el: P1-P14 Transfer sect. el.: T1-T6 HV1 HV2 HV3 e- gun 75 cm Target for Ps formation Trap radius 1.25 cm e+ Ps Hbar Production region 1T 5 T Trap radius 0.5 cm

AEgIS detectors T-line “Kicker pulser ” (or e+ pick-up amplifier) PbF2 + PMT readout (e+) T-line “Kicker pulser ” (or e+ pick-up amplifier) PbF2 + PMT readout (e+) Plastic scintillators (PMT readout: either digitized or counting mode) Plastic Scintillator (HPD readout) Si Beam counter RF tuned circuit and 4 KCryoamp (axial e- detection) Al Faraday Cup (facing trap and e+transf line) NE111+ PMT readout (e+) 1T MCP + Phosphor+ CMOS camera (facing 1T traps) T-line CsI Cryo PbF2 (e+) 5TMCP+Phosphor+CCD camera (facing traps) Central Region FC (Sectors of Au plated Cu facing both sides) Cryoamp 2 (radial pbar det) FACT 800 scint fibers+ SiPm 24 fibers signal digitized

Attivita’ del gruppo di Genova Cattura, raffreddamento pbar con plasmi di elettroni Compressione radiale plasmi misti confinati Trasporto pbar 5T- 1T Cooling in1T Trasporto e+ nei magneti principali Eccitazione laser Ps

Mixed plasma compression Example: Pbar cooling We routinely trap 3.5 105 pbar@9KV Fast (tens ns 9 KV pulse- developed in Genoa) Cooling with e- @5T to few tens K Compression via RF of mixed e- and pbar plasma (Coll. paper ready to be submitted, Genoa resp.) MCP+Phosph+CCD e-=4.4 108 e->109 Mixed plasma compression Residual not cooled pbar: a) 35% with about 4.4 108 e- b) 3% with > some 109 e- Cold pbar on 5TMCP

Pbar cloud: about 0.3 mm radius@1T Transport of compressed pbar plasma 5T-1T Pbar follow magnetic field lines Issue: 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) Pbar cloud: about 0.3 mm radius@1T 2 mm Pretransfer& no shift pbar run 60402 Pretransfer& shift pbar run 67468

e+ direct injection e+ pbar 2) Direct e+ injection 1T magnet 5T magnet Not to scale e+ 1T magnet 5T magnet Magnetic pulsed transfer line 1T traps 5T traps Off axis pbar On axis AEgIS 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 Daniel K.

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: OK Eccitazione Ps in 1T: in progress (primi segnali??) Trasporto pbar nella regione formazione Hbar: OK Cooling pbar in regione formazione Hbar : OK Temperatura @1T : in progress in queste settimane Commissioning rivelatore Hbar : in progress (no Genova) Formazione Hbar: prossimo goal immediato

Oltre alla presa dati Upgrade della trappola formazione Hbar (disegno, costruzione) Test a Genova in L202 (?) Impegni servizi: Progettazione meccanica 4-6 mesi Officina meccanica 2-3 mesi Officina 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 Phase shift Direct g measurement (WEP test) Counts vs vertical coordinate 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 statistics L=few tens cm Grating period a : few tens mm High resolution position detector : few mm Shift of the periodic pattern due to vertical forces (gravity) Phase 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 T EXB with electric field in the position of B0 electrode Recatch in OnAx28-UC15 & dump See the plasma center as a function of the B0 voltage