1 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Neutrino Factory Cryostat 1 Concept

V.B. Graves

MERIT VideoconferenceMar 11, 2009

2 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Study 2 Cryostat Schematic (Fig 3.4)

• Target containment extends to end of SC-5– Be window also at this location

• Overflow drain at left end of pool determines pool depth• Jet travels through a splash mitigator prior to entering pool• Containment encompasses nozzle tip

3 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

IronPlug

ProtonBeam

NozzleTube

SC-1

SC-2 SC-3 SC-4SC-5

Window

MercuryDrains

MercuryPool

Water-cooledTungsten ShieldMercury

Jet

ResistiveMagnets

Neutrino Factory Study 2 Target Concept

ORNL/VGMar2009

SplashMitigator

4 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Cryostat 1 Upstream End

5 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Front View

• Includes slope for Hg drainage– Could potentially drain

under resistive magnets

• Mechanical issues between nozzle and beam– Will be worse if Hg is

double-contained

• Iron plug restraints will be an issue• Splash mitigation

scheme incorporated• Relatively thin beam

stop (Hg depth)

6 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Cryostat 1 Downstream End

• Window becomes a liquid barrier– Window actually on

replaceable component

• Drainage piping relatively flat for some distance• Mercury pool serves

as additional SC shielding

SC-5

Window

OverflowDrain

ValvedDrain

TungstenShielding

7 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

NF Cryostat 1 Dimensional Info

Based on Study II Tables 3.13, 3.14Dimensions in cm

8 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

NF Hg Jet Layout

9 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Study 2 Mercury Containment Vessel Alternate

• Another containment approach includes a shortened Hg container• Drain lines exit cryostat

between SC-3 and SC-4• This would trap container in

the cryostat, preventing future replacement

10 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Containment Design Requirements

• Material compatible with high-field magnets– Must also withstand some number of full-power beam pulses

with no Hg in vessel (accident scenario)

• Desire no replaceable components• Provide support for Hg weight– ~220 liters, 3 metric tons

• Sloped (1°-2°) for gravity drain• Overflow drain for 20m/s jet (1.6 liter/s)• Vent for gas transfer

11 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Splash Mitigation

• Study 2 assumed a particle bed of tungsten balls to minimize effects of jet entering pool• Many other feasible concepts

to accomplish this function• Simulation/analytical studies

may be useful to limit options• Pool circulation and drainage

locations also need to be studied• Prototypic testing needed for

comparison & final determination

12 Managed by UT-Battellefor the U.S. Department of Energy MERIT Videoconference 11 Mar 2009

Summary

• 3D conceptual model of a Neutrino Factory main cryostat is being refined• Design and integration of this cryostat with a Hg

containment vessel is very complicated– Mechanical issues may require physics compromises

• IDS is only funding avenue potentially available for serious design work