New group at RWTH Aachen UniversityIII. Physikalisches Institut B

Prof. Achim Stahl / Prof. Christopher Wiebusch

Main activities:CMS (Si-Tracker, data analysis, Tier-2)Double Chooz / T2K / IceCubeGRID computing & applications in medical physics

beta-beams:group of under-graduate students

Marcel Weifels – Michaela Schaumann – Bastian Kargoll – Jakob Wehner – Markus Lauschergoal: conceptional layout and physics potential for beta-beams at DESY

Achim Stahl – RWTH Aachen University 23-Oct-2008

View beta-beams as part of a European neutrino program

Laguna: Large Neutrino Detector as core of the program

LENA LENA oror GLACIERGLACIER or or MEMPHISMEMPHIS

Physics Goals:Geo-Physics: Neutrinos from the core of the earth; heat release

from the core; relevant for our climatParticle Physics: Proton decay; unification of forces, GUT theories

large volume detector!Particle Physics: Neutrino oscillations; atmospheric , reactor

(depends on detector technology), accelerator :beta-beams & super beam: CP-violation, origin of matter

Astrophysics: Observation of -emission from super-novaeSN1987A hundreds of observations

Nuclear Physics: Understanding -cross sections, i.e. cooling of super novae

Potential tests of discrete symmetries

Potential tests of discrete symmetries

CExample:Test of charge conjugation

C-violation implies P-violation,if CP is conserved.

Potential tests of discrete symmetries

T

Example:Test of time invariance

CPT-theorem:T violation implies CP violation

Need e beam and beam

Potential tests of discrete symmetries

T

Example:Another possibility to test Tinvariance.

Need e beam and beam

Potential tests of discrete symmetries

CPT

Example:additional CPT tests and systematic checks with

neutrino and antineutrinos

Need e beam and beam

conventional -beamfrom pion-decay&&

e / e beam / beam

conventional -beamfrom the SPL

LHC upgrade scenario

Need e beam and beam

conventional -beamfrom pion-decay&&

optimal baseline(1st oscillation max.)

optimal baseline(1st oscillation max.)

134 km @ 1 GeV 300 km @ = 1501000 km @ = 500

e / e beam / beam

detector

optimal baseline

optimal baseline e

1 detector only (price)

hard to accomodate bothbaselines from one lab.

300 km @ = 1501000 km @ = 500

134 km @ 1 GeV

DESY

L=960 km

Kinematics:

Event rate in the detector (for fixed number of decays in the decay ring):

dep. on Opening angle ~ 1/ flux at fixed distance ~ 2

Elab ~ optimal baseline ~ flux at detector ~ 1/2

Elab ~ cross section ~

~

dep. on E*

Opening angle independent of E*

Elab ~ E* optimale Baseline ~ E* flux at detector ~ 1/E*2

Elab ~ E* cross section ~ E*

~ 1/E*

Inside the long HERA tunnel which was just shutdown before we came to DESY. The experiments ( like ZEUS in the previous photo ) are being dismantled. Asking the CEO of DESY what they will do with HERA after they have dismantled the experiments he just shrugged and said that they currently have no idea?!?

Comment from the summer student who took the picture

for beta-beams:

reuse tunnel

dipoles unusable

can we use ?• cryo plant• power supplies• vacuum equipment • …

12 T dipole2 x 35 m length

Injection

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Dec

ay s

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appr

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, poi

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wn

at 5

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wes

t poi

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00m

bel

ow H

ERA

Pre

acc

ele

rato

r„H

alle

West

“

accelerator in HERA tunnel used as

decay ring and for final acceleration

12 T dipole35 m length

Preaccelerators

final energy 50 MeV2 bunch trains: 400 bunches

final energy 4.7 GeV corresponding = 0.8

final energy 120 GeV after 5 turnsTESLA linac 35 MV/m

final energy 1.4 TeV (=500)ramp at 0.5 T/sec (20 sec tot.)500 sec decay at max. energydeaccelerate and dump

Is 6He the best isotope ?500 sec lifetime at =500

Time Structure & Intensity

bunch trains:2 trains800 m long (2.7 sec)3469 bunches1.3 GHz frequency

structure of cycles:creation of ions: 0.1 secpreacceleration: 20 secramp of main ring: 20 sec < 20% lossactive decays: 400 sec ~ 22% in straight sectiondeaccelerate: 20 sec

sum: ~ 500 sec

intensity (100% efficiency !):2.6 1010 ions per bunch2.7 1013 usefull per cycle5.8 1017 per year

We cannot afford a copy of EURISOL at DESY Most likely the largest problem !

Try an idea from T. Hirsch/M. Hass Weizmann

ionization bunching linac

SARAF @ Weizmann: 40 MeV d-Beam 2 mA

we need 3.6 1011 ions/sec

but very different time structure

a dream ?

bunches

thin target

can it work like that ?

I‘ll stop speculating here

Have not thought about 18Ne

FP6 scenario

Plots from Walter Winter / Patrick Huber

beta-beam @ DESYSuper-beam from SPLWater-Cerenkov Det @ Frejus

very similar sensitivity

• We hope to become an associate member of the FP7

project

• Cooperation with FZ Jülich (COSY) has started

• First discussions with DESY

• Workshop on future particle & nuclear physics projects on

13./14. November in Frankfurt

• Will apply for funding starting July 2009

Main topics for our work

• Conceptional layout

• Ion source

• Physics studies