RNB 6 The beta-beam study group

The Beta-beamhttp://beta-beam.web.cern.ch/beta-beam/

Mats Lindroos on behalf of the

The beta-beam study group

RNB 6 The beta-beam study group

CERN: -beam

baseline scenario

PS

Decay

RingISOL target & Ion source

SPL

Cyclotrons, linac or FFAG

Decay ring

Brho = 1500 Tm

B = 5 T

Lss = 2500 m

SPS

ECR

Rapid cycling synchrotron

MeV 86.1 Average

MeV 937.1 Average

189

1810

63

62

cms

cms

E

eFeNe

E

eLiHe

Nuclear Physics

,

,

RNB 6 The beta-beam study group

Beam parameters in the

decay ring18Neon10+ (single target)– Intensity: 4.5x1012 ions – Energy: 55 GeV/u– Rel. gamma: 60– Rigidity: 335 Tm

• The neutrino beam at the experiment should have the “time stamp” of the circulating beam in the decay ring.

• The beam has to be concentrated to as few and as short bunches as possible to maximize the number of ions/nanosecond. (background suppression)

6Helium2+

– Intensity: 1.0x1014 ions – Energy: 139

GeV/u– Rel. gamma: 150– Rigidity: 1500 Tm

RNB 6 The beta-beam study group

Layout very similar to planned EURISOL converter target aiming for 1015 fissions per s.

66He production by He production by 99Be(n,a)Be(n,a)

Converter technology: (J. Nolen, NPA 701 (2002) 312c)

RNB 6 The beta-beam study group

Scenario 1Scenario 1

• Spallation of close-by target nuclides:18,19Ne from MgO and 34,35Ar in CaO

– Production rate for 18Ne is 1x1012 s-1 (with 2.2 GeV 100 A proton

beam, cross-sections of some mb and a 1 m long oxide target of 10%

theoretical density)

– 19Ne can be produced with one order of magnitude higher intensity

but the half life is 17 seconds!

Scenario 2Scenario 2

• alternatively use (,n) and (3He,n) reactions:

12C(3,4He,n)14,15O, 16O(3,4He,n)18,19Ne, 32S(3,4He,n)34,35Ar

– Intense 3,4He beams of 10-100 mA 50 MeV are required

Production of Production of ++ emitters emitters

RNB 6 The beta-beam study group

60-90 GHz « ECR Duoplasmatron » for

gaseous RIBVery high density

magnetized plasmane ~ 1014 cm-3

2.0 – 3.0 T pulsed coils or SC coils

60-90 GHz / 10-100 KW10 –200 µs / = 6-3 mm

optical axial coupling

optical radial coupling(if gas only)

1-3 mm100 KV

extractionUHF windowor « glass » chamber (?)

Target

Rapid pulsed valve

20 – 100 µs20 – 200 mA

1012 to 1013 ions per bunchwith high efficiency

Very small plasmachamber ~ 20 mm / L ~ 5 cm

Arbitrary distanceif gas

Moriond meeting:

Pascal Sortais et al.

LPSC-Grenoble

RNB 6 The beta-beam study group

Overview:

Accumulation

• Sequential filling of 16 buckets in the PS from the storage ring

RNB 6 The beta-beam study group

SPS

Overview: Decay ring

• Ejection to matched dispersion trajectory

• Asymmetric bunch merging

SPSSPS

RNB 6 The beta-beam study group

S. Hancock

Asymmetric bunch merging

RNB 6 The beta-beam study group

Asymmetric bunch

merging

60 40 20 0 20 40 60ns

4

2

0

2

4

MeV

0

0.1

0.2

0.3

0.4

0.5

A

4014

3014

2014

1014 0

eVe

0 5 10 15 20 25Iterations

0

8.17 1011

esVe

rms 0.0585 eVs BF 0.16

matched 0.298 eVs Ne 1.57 1011

2 prmsp 1.2 103 fs0;1 822;790 Hz

60 40 20 0 20 40 60ns

4

2

0

2

4

MeV

0

0.1

0.2

0.3

0.4

0.5

A

4014

3014

2014

1014 0

eVe

0 5 10 15 20 25Iterations

0

8.1 1011

esVe

rms 0.0639 eVs BF 0.168

matched 0.323 eVs Ne 1.6 1011

2 prmsp 1.25 103 fs0;1 823;790 Hz

125 100 75 50 25 0 25 50ns7.5

5

2.5

0

2.5

5

7.5

MeV

0

0.1

0.2

0.3

0.4

0.5

0.6

A

4014

3014

2014

1014 0

eVe

0 5 10 15 20 25Iterations

0

8.52 1011

esVe

rms 0.0583 eVs BF 0.14

matched 0.317 eVs Ne 1.63 1011

2 prmsp 1.34 103 fs0;1 0;1060 Hz

100 75 50 25 0 25 50 75ns4

2

0

2

4

MeV

0

0.1

0.2

0.3

0.4

A

6014

5014

4014

3014

2014

1014 0

eVe

0 10 20 30 40 50Iterations

0

8.16 1011

esVe

rms 0.0593 eVs BF 0.224

matched 0.333 eVs Ne 1.56 1011

2 prmsp 8.5 104 fs0;1 0;415 Hz

RNB 6 The beta-beam study group

Decay losses• Losses during acceleration are being

studied:– Full FLUKA simulations in progress for all

stages (M. Magistris, CERN-TIS)– Preliminary results:

• Can be managed in low energy part• PS will be heavily activated

– New fast cycling PS?• SPS OK!• Full FLUKA simulations of decay ring losses:

– Tritium and Sodium production surrounding rock well below national limits

– Reasonable requirements of concreting of tunnel walls to enable decommissioning of the tunnel and fixation of Tritium and Sodium

A. Jansson

RNB 6 The beta-beam study group

SC magnets• Dipoles can be built

with no coils in the path of the decaying particles to minimize peak power density in superconductor– The losses have been

simulated and a first dipole design has been proposed

S. Russenschuck, CERN

RNB 6 The beta-beam study group

Tunnels and Magnets• Civil engineering costs: Estimate of 400 MCHF for 1.3%

incline (13.9 mrad)– Ringlenth: 6850 m, Radius=300 m, Straight sections=2500 m

• Magnet cost: First estimate at 100 MCHF

FLUKA simulated losses in surrounding rock (no public health implications)

RNB 6 The beta-beam study group

IntensitiesStage 6He 18Ne (single

target)

From ECR source: 2.0x1013 ions per second

0.8x1011 ions per second

Storage ring: 1.0x1012 ions per bunch

4.1x1010 ions per bunch

Fast cycling synch: 1.0x1012 ion per bunch 4.1x1010 ion per bunch

PS after acceleration:

1.0x1013 ions per batch 5.2x1011 ions per batch

SPS after acceleration:

0.9x1013 ions per batch 4.9x1011 ions per batch

Decay ring: 2.0x1014 ions in four 10 ns long bunch

9.1x1012 ions in four 10 ns long bunch

Only -decay losses accounted for, add efficiency losses (50%)

RNB 6 The beta-beam study group

Conclusions• Physics:

– Super beam, beta-beam and FREJUS: WORLD unique– Low energy beta-beam: Nuclear Physics!

• Design study proposal as part of EURISOL is now being prepared– You are welcome to join (contact

Mats.Lindroos@cern.ch or Michael.Benedikt@cern.ch)

• New ideas are being further studied and could give very important improvements to the physics reach

• Workshop on Exploring the Impact of New Neutrino Beams, ECT*, Trento, Italy, 18-22 October 2004, (C. Volpe, J. Bouchez, M. Lindroos, M. Mezzetto, T. Nilsson)

RNB 6 The beta-beam study group

Collaborators• The beta-beam study group:

– CEA, France: Jacques Bouchez, Saclay, Paris Olivier Napoly, Saclay, Paris Jacques Payet, Saclay, Paris

– CERN, Switzerland: Michael Benedikt, AB Peter Butler, EP Roland Garoby, AB Steven Hancock, AB Ulli Koester, EP Mats Lindroos, AB Matteo Magistris, TIS Thomas Nilsson, EP Fredrik Wenander, AB

– Geneva University, Switzerland: Alain Blondel Simone Gilardoni– GSI, Germany: Oliver Boine-Frankenheim B. Franzke R. Hollinger

Markus Steck Peter Spiller Helmuth Weick – IFIC, Valencia: Jordi Burguet Juan-Jose Gomez-Cadenas Pilar Hernandez – IN2P3, France: Bernard Laune, Orsay, Paris Alex Mueller, Orsay, Paris

Pascal Sortais, Grenoble Antonio Villari, GANIL, CAEN Cristina Volpe, Orsay, Paris

– INFN, Italy: Alberto Facco, Legnaro Mauro Mezzetto, Padua Vittorio Palladino, Napoli Andrea Pisent, Legnaro Piero Zucchelli, Sezione di Ferrara

– Louvain-la-neuve, Belgium: Thierry Delbar Guido Ryckewaert UK: Marielle Chartier, Liverpool university Chris Prior, RAL and Oxford university

– Uppsala university, The Svedberg laboratory, Sweden: Dag Reistad

– Associate: Rick Baartman, TRIUMF, Vancouver, Canada Andreas Jansson, Fermi lab, USA