1. Henryk Piekarz SC Magnets at Fermilab A Double, 480 GeV, Fast Cycling Proton Accelerator for Production of Neutrino Beams at Fermilab Outline 1.Motivation 2.Physics potential of long-baseline neutrino experiments 3.Possible detector sites for Fermilab long-baseline neutrino beams 4.Proposed new Fermilab accelerator complex 5.Magnets for fast cycling DSF-MR accelerator 6.Power supply system for DSF-MR 7.Neutrino production beam lines 8.Projected cost and timeline 9.Summary and conclusions More details in: Fermilab Note TM-2381-AD-TD http://tdserver1.fnal.gov/project/Nu-factory/DSF-MR.doc I would like to acknowledge invaluable contributions of: Steven L. Hays, Yuenian Huang, Vadim Kashikhin, Gijs de Rijk and Lucio Rossi as well as helpful discussions with Sacha Kopp and Bob Zwaska

2. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Motivation  Startup of LHC in 2008 brings end to the Tevatron  ILC with its primary motivation to study Higgs must wait for Higgs discovery to determine necessary mass reach  It is likely to take few years for LHC to confirm or deny existence of SM Higgs (M Higgs < 0.8 TeV)  The US high-energy physics community must have an intermediate, high-profile, accelerator-based program  Intermediate program should be of moderate cost, so not to affect potential ILC construction in the future  Long-baseline neutrino oscillation search experiments may match the requirement of a high-profile physics at a moderate cost

3. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Physics potential of long baseline neutrino oscillation experiments  As limits on ∆ m ( ν α, ν β ) get smaller the baseline, L, must be increased as: P ( ν α-> ν β) ~ ∆ m ( ν α, ν β) x L x 1/E ν  At current longest baselines (750 km, or so), the interpretation of results is uncertain due to 8- fold degeneracy of theory parameters  It has been shown recently that there exist baseline at which parameter degeneracy is suppressed, and e.g. angle Θ (ν µ-> ν e) will be directly measured. This “magic” baseline depends only on matter density: L magic = 32726 / ρ [g/cm 3 ] => ~ 7250 km for ρ = 4.3 g/cm 3 of Earth’s density profile  In addition, a combination of results at ~7500 km and ~3000 km allows to increase parameters sensitivity by > 3 order of magnitude (Peter Huber and Walter Winter, MTP-PhT/2003-05) Experiment Baseline [km] Sin 2 θ 13 δ CP Mass hierarchy MINOS 735 > 0.05 NO CNGS 732 > 0.02 NO New Exp. 7500 + 3000 0.00005 YES

4. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Long baseline neutrino detector sites considered for CERN neutrino beams  Magic baseline INO – Indian Neutrino Observatory, 2 sites considered: 1. Ramman, N 27.4, E 88.1 2. Pushep, N 11.5, E 76.6 Distance to CERN for both ~ 7125 km INO is a serious, well documented proposal of 2006 !  The “~3000 km” baseline - Santa Cruz (Canary Islands, Spain), 2750 km - Longyearbyen (Iceland, Norway), 3590 km - Pyhaesalami (Finland), 1995 km

5. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Potential detector sites for 7500 km baseline from Fermilab  Only in Europe (excluding permafrost region of Chukotka), - e.g. Gran Sasso in Italy: ~750 km from CERN, and ~ 7500 km from Fermilab

6. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Potential detector site at ~ 3000 km  The ~ 3000 km baseline must be found within US  Mount Whitney: peak 4348 m, prominence ~ 3000 m, granite, non-seismic. At its foothill – city of Loan Pine, CA 93545 (airport, golf, hotels) => seems to be a perfect site for a neutrino detector at 2700 km away from FNAL Sierra Nevada Mountain Ridge with MT Whitney (center)Baseline from FNAL to Loan Pine

7. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Potential detector site at ~ 1500 km, and possible use of MINOS and Nova  Henderson, Co (39.29N, 104.865W), ~ 1500 km from Fermilab  Mount Harrison, mostly granite, 3968 m (prominence 1550 m)  Existing mine considered for the Underground Neutrino Observatory The MINOS experiment (735 km) and Nova (810 km) would also greatly benefit from the multi-fold increased neutrino beam intensity with DSF-MR !!!

8. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Proton and neutrino beams energy  The beam power at the neutrino production target is directly proportional to the proton energy  With the increase of proton energy using higher energy neutrinos may be advantageous as shown below Proton Energy [GeV] L [km] E ν [GeV] POT / Y [ x 10 19 ] Limit of Sin 2 θ 13 FNAL - NUMI 120 735 3 36 > 0.05 CERN - CNGS 400 732 17.4 4.5 > 0.02

9. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Proposed new Fermilab accelerator complex  Install two, 480 GeV, fast cycling accelerator rings in MR tunnel  The 4-fold energy increase and stacking 2 MI beams in DSF-MR give 8-fold increase in beam power on neutrino production target  Extract proton beams onto up to 5 neutrino production targets to produce interchangeably neutrino beams to detectors in Europe, Mt Whitney, Mt Harrison, Noνa and Minos in US

10. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Operation & timing sequence for DSF-MR beams  LINAC and Main Injector will be “recharged” every second, and SF-MR1 and SF-MR2 will receive beam every 2 seconds

11. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Beam power on target with DSF-MR Fermilab Accelerator System Ion Source Rep. Rate [Hz] Pulse Length [msec] Protons per Cycle [x 10 14 ] Beam Energy [GeV] Beam Power FNAL | BNL [MW] Present (Proton Plan) 15 0.09 0.45 120 0.40 0.74 Present + DSF-MR 15 0.09 0.90 480 3.20 5.90 SNuMi I (R) + DSF-MR 15 0.09 0.49 0.98 120 480 0.70 1.30 5.60 10.4 SNuMi II (A) + DSF-MR 15 0.09 0.83 1.66 120 480 1.20 2.20 9.60 17.8 8 GeV Linac (HINS – exp.) BNL 10 5 1.00 0.5 1.50 0.70 120 2.20 0.55 This BNL H- source (Jim Alessi) has been successfully operating for more than 2 decades.

12. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Sizing the detectors Detector and/or Location Distance [km] Detector size – Proton Plan [kton] Detector size – Proton Plan + DSF-MR [kton] MINOS, MI 735 5.4 (0.7) (0.4) NOVA, MI 810 25 3.1 (1.7) Henderson, CO 1500 22 2.8 (1.5) Mt Whitney, CA 2700 73 10 (5.4) Gran Sasso, IT 7500 573 66 (36) Detector size is scaled relative to the data flow at MINOS (…) with BNL H- source

13. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting DSF-MR magnets The DSF-MR accelerator main arc magnet is a combined function dipole: - Window frame laminated, Fe3%Si core offers high quality B-field at full 2 Tesla range, high mechanical stability, and a simple (cheap) assembly work - A superconducting transmission line powers the entire accelerator magnet string producing a 2 Tesla field in a 40 mm gap with 87 kA current in the conductor - There is only one power supply and one set of current leads per accelerator ring - Cryogenic support per accelerator ring is expected at (10-20) % of the Tevatron level - 3 papers on DSF-MR/SF-SPS magnet, power supply and current leads will be presented at MT21, Philadelphia, August 27-30, 2007 ¼ of magnet core

14. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting DSF-MR magnets  We base the DSF-MR magnet list on the SF-SPS *) preliminary design (same circumference and beam energy): Cell type Magnet type Magnet length [m] B- field [T] B’ –field [T/m] Number per ring Arc sections GF/GD QF QTF 7.165 0.660 0.339 1.9 +/- 4.7 +/- 70.00 744 6 Straight sections QF/QD 0.660+/- 70.00 48 Total 804 *) http://tdserver1.gnal.gov/project/Nu-factory/Lumi-06-paper.doc

15. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting DSF-MR power systems - Each DSF-MR accelerator ring supply ramps out of phase allowing to share common harmonic filter and feeder systems - Each supply will be +/- 2 kV ramping supply at 100 kA and 198 MVA - Existing Tevatron power transformers can be reconfigured to support DSF-MR

16. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting DSF-MR power systems  The DSF-MR power supply design is based on the MI supply. A ¼ of the proposed DSF-MR power supply is shown below:

17. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Neutrino production lines Sketch of neutrino production lines for 1500, 2700 and 7500 km long baselines.

18. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Neutrino production lines  The strong descent of the proton lines to the production targets is a significant civil engineering challenge. Most of the beam path (~1000 m), however, is a decay tube for π/K -> µ + ν.  With 42 0 descending angle the neutrino target will have to be at a depth of ~ 700 m. For comparison the Soudan detector is at ~ 700 m below the surface.  The Tevatron magnets may be used to construct some parts of the transfer lines from DSF-MR to neutrino production targets All neutrino beam lines will fit inside the FNAL proper.

19. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Cost estimate DSF-MR Subsystem [$M] Main arc magnets, including conductors, current leads and power supplies 200 Main arc corrector magnets 10 Main Injector to DSF- MR transfer lines 10 DSF-MR RF system (Tevatron upgrade) 40 Beam pipe vacuum system 15 Cryogenic plant and distribution upgrade 10 Magnet & power supply R&D and prototyping 5 Total 300 Cost of three 1000 m long neutrino production lines is estimated at ~ $M 225: - $M 150 (42 deg.) - $M 50 (15 deg.) - $M 25 (7 deg.) Total cost: ~ $M 525 Contigency 33%: ~ $M 175 Grand total: ~ $M 700 Outline of Magnet & Power Supply R&D and cost estimate is given in: http://tdserver1.fnal.gov/project/Nu-factory/LARP- FSM-cost.dochttp://tdserver1.fnal.gov/project/Nu-factory/LARP- FSM-cost.doc and in: http://tdserver1.fnal.gov/project/Nu-factory/Cost-ps- slh-v2.xls Magnet & Power Supply R&D estimated at $ 0.6 M over 2 years !!

20. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Timeline Activity Time [Y] Lapsed time [Y] DSF-MR design 1 1 Magnet R&D 2 2 Power supply R&D 2 2 DSF-MR magnet production 3 5 Magnet rings installation 3 5 Neutrino beam lines 2 5 Neutrino targets 2 5 Neutrino detectors 2 5 DSF-MR commissioning 1 6

21. Henryk Piekarz SC Magnets at Fermilab June 4, 2007Steering Group meeting Summary & Conclusions  DSF-MR accelerator will: - open new opportunity to probe particle mass scales well beyond the SM with neutrino mass reach up to ~ 0.00005 eV - utilize and preserve the potential of Fermilab as a major US/World HEP Institution for the next 2 decades, or so  The DSF-MR can also serve as: (1) Neutrino fixed target experiments (e.g. Janet Conrad’s ν µ scattering) (2) 480 GeV proton source for the ILC detector tests (3) 6 GeV Electron Damping Ring for ILC tests ( only in desperation – with 2 Tesla DSF-MR magnets a ring of ~200 m circumference will do it)  The cost of the DSF-MR is about the same as that of the 8 GeV HINS, and with 3 new neutrino beam lines it is at ~ 10 % level of the ILC, so it will not impede the ILC, or any other next large-scale HEP project in US