Henryk Piekarz SC Magnets at Fermilab A Double, 480 GeV, Fast Cycling Proton Accelerator for Production of Neutrino Beams at Fermilab Outline 1.Motivation

Henryk Piekarz

SC Magnetsat Fermilab

A Double, 480 GeV, Fast Cycling Proton Accelerator for Production of

Neutrino Beams at Fermilab

Outline

1. Motivation2. Physics potential of long-baseline neutrino experiments3. Possible detector sites for Fermilab long-baseline neutrino beams4. Proposed new Fermilab accelerator complex5. Magnets for fast cycling DSF-MR accelerator6. Power supply system for DSF-MR7. Neutrino production beam lines8. Projected cost and timeline9. 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

June 4, 2007 Steering Group meeting Henryk Piekarz


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



Physics potential of long baseline neutrino oscillation experiments

As limits on ∆ m(να,νβ) get smaller the baseline, L, must be increased as:

P(να->νβ) ~ ∆ m(να,νβ) x L x 1/Eν 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 (νµ->νe) will be directly measured. This “magic” baseline depends only on matter density:

L magic = 32726 / ρ [g/cm3] => ~ 7250 km for ρ = 4.3 g/cm3 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]

Sin2 θ13 δCP Masshierarchy

MINOS 735 > 0.05 NO NO

CNGS 732 > 0.02 NO NO

New Exp.

7500 + 3000

0.00005 YES YES



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



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



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



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 !!!



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 1019 ]

Limit of Sin2 θ13

FNAL -NUMI 120 735 3 36 > 0.05

CERN -CNGS 400 732 17.4 4.5 > 0.02



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



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



Beam power on target with DSF-MR

FermilabAcceleratorSystem

Ion SourceRep. Rate [Hz]

Pulse Length [msec]

Protons per Cycle [x 1014]

Beam Energy [GeV]

Beam PowerFNAL | 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

120 120

2.20 0.55

This BNL H- source (Jim Alessi) has been successfully operating for more than 2 decades.



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



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



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+/- 70.00

744 6 6

Straightsections

QF/QD 0.660 +/- 70.00

48

Total 804

*) http://tdserver1.gnal.gov/project/Nu-factory/Lumi-06-paper.doc



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



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:



Neutrino production lines

Sketch of neutrino production lines for 1500, 2700 and 7500 km long baselines.



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 420 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 insidethe FNAL proper.



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 525Contigency 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.doc and in:http://tdserver1.fnal.gov/project/Nu-factory/Cost-ps-slh-v2.xlsMagnet & Power Supply R&D estimated at $ 0.6 Mover 2 years !!



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



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

Documents

Henryk Piekarz SC Magnets at Fermilab A Double, 480 GeV, Fast Cycling Proton Accelerator for Production of Neutrino Beams at Fermilab Outline 1.Motivation