Beta-beams at DESY

1. Beta-beams at DESY New group at RWTH Aachen University III. Physikalisches Institut B Prof. Achim Stahl / Prof. Christopher Wiebusch Main activities: CMS (Si-Tracker, data analysis, Tier-2) Double Chooz / T2K / IceCube GRID computing & applications in medical physics beta-beams: group of under-graduate students Marcel Weifels – Michaela Schaumann – Bastian Kargoll – Jakob Wehner – Markus Lauscher goal: conceptional layout and physics potential for beta-beams at DESY Achim Stahl – RWTH Aachen University 23-Oct-2008

2. A European Neutrino Program View beta-beams as part of a European neutrino program Laguna: Large Neutrino Detector as core of the program LENA or GLACIER or MEMPHIS Physics Goals: Geo-Physics: Neutrinos from the core of the earth; heat release from the core; relevant for our climat Particle Physics: Proton decay; unification of forces, GUT theories large volume detector! Particle Physics: Neutrino oscillations; atmospheric n, reactor n (depends on detector technology), accelerator n: beta-beams & super beam: CP-violation, origin of matter Astrophysics: Observation of n-emission from super-novae SN1987A  hundreds of observations Nuclear Physics: Understanding n-cross sections, i.e. n cooling of super novae

3. Observing CP Violation Potential tests of discrete symmetries

4. C Example: Test of charge conjugation C-violation implies P-violation, if CP is conserved. Observing CP Violation Potential tests of discrete symmetries

5. Observing CP Violation Potential tests of discrete symmetries Example: Test of time invariance CPT-theorem: T violation implies CP violation T Need ne beam and nm beam

6. Observing CP Violation Potential tests of discrete symmetries Example: Another possibility to test T invariance. T Need ne beam and nm beam

7. Observing CP Violation Potential tests of discrete symmetries Example: additional CPT tests and systematic checks with neutrino and antineutrinos CPT

8. Why Hamburg ? Need ne beam and nm beam conventional n-beam from pion-decay & nm / nmbeam ne / nebeam

9. Why Hamburg ? LHC upgrade scenario conventional n-beam from the SPL

10. Why Hamburg ? Need ne beam and nm beam conventional n-beam from pion-decay & nm / nmbeam ne / nebeam optimal baseline (1st oscillation max.) optimal baseline (1st oscillation max.) 134 km @ 1 GeV 300 km @ g = 150 1000 km @ g = 500

11. Why Hamburg ? 1 detector only (price) hard to accomodate both baselines from one lab. 134 km @ 1 GeV detector optimal baseline nm 300 km @ g = 150 1000 km @ g = 500 optimal baseline ne

12. L=960 km DESY

13. Kinematics: Event rate in the detector (for fixed number of decays in the decay ring): dep. on g Opening angle ~ 1/g  flux at fixed distance ~ g2 Elab ~ g  optimal baseline ~ g flux at detector ~ 1/g2 Elab ~ g  cross section ~ g ~ g 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*

14. Status of HERA • for beta-beams: • reuse tunnel • dipoles unusable • can we use ? • cryo plant • power supplies • vacuum equipment • … Comment from the summer student who took the picture 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?!?

15. Conceptional Layout accelerator in HERA tunnel used as decay ring and for final acceleration 12 T dipole 35 m length Decay section approx. 22% of the ring, pointing down at 5°, lowest point 100m below HERA Preaccelerator „Halle West“ Acceleration 12 T dipole 2 x 35 m length Injection

16. Conceptional Layout Preaccelerators final energy 1.4 TeV (g=500) ramp at 0.5 T/sec (20 sec tot.) 500 sec decay at max. energy deaccelerate and dump final energy 120 GeV after 5 turns TESLA linac 35 MV/m final energy 4.7 GeV corresponding b = 0.8 final energy 50 MeV 2 bunch trains: 400 bunches Is 6He the best isotope ? 500 sec lifetime at g=500

17. Conceptional Layout Time Structure & Intensity bunch trains: 2 trains 800 m long (2.7 msec) 3469 bunches 1.3 GHz frequency structure of cycles: creation of ions: 0.1 sec preacceleration: 20 msec ramp of main ring: 20 sec  < 20% loss active decays: 400 sec  ~ 22% in straight section deaccelerate: 20 sec sum: ~ 500 sec intensity (100% efficiency !): 2.6 1010 ions per bunch 2.7 1013 usefull n per cycle 5.8 1017n per year

18. Ion Source 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 we need 3.6 1011 ions/sec but very different time structure SARAF @ Weizmann: 40 MeV d-Beam 2 mA

19. Ion Source a dream ? bunches thin target

20. Ion Source can it work like that ? I‘ll stop speculating here Have not thought about 18Ne

21. Physics Reach FP6 scenario Plots from Walter Winter / Patrick Huber

22. Physics Reach beta-beam @ DESY Super-beam from SPL Water-Cerenkov Det @ Frejus very similar sensitivity

23. Future Plans • 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