Status of hornsStatus of hornsStatus of hornsStatus of horns

A.K.IchikawaA.K.Ichikawa

1st Horn 2nd Horn 3rd Horn

Graphite Targetbeam I=320kA

Activities• T. Sekigutchi joined the target-horn group.• US group (E.D.Zimmerman, J.Spitz, L.Bartos

zek) have contributed on beam MC study, design of horns.

• Other contributions by T. Nakadaira, S. Tada, Y. Yamada, S. Koike, Y. Suzuki, T. Kobayashi et al.

Overview of Target Station

Iron

Shield

(2.2m)

Concrete

shield(1m)

Iron structure (= helium vessel) supports horns and shields

Supportingpoints

Beam MC study by J. Spitz• J.Spitz’s report is available at

http://jnusrv01.kek.jp/jnu/tgt-horn/beamMC• Effects of mis-alignment -> Covered at the last collab.

meeting• Effects of the horn current drop• Effects of beam angle deflection• Possible beam plug at 4MW

Nu-mu flux at Super-K vs. Horn 1 Current Drop

1.12E+07

1.13E+07

1.14E+07

1.15E+07

1.16E+07

1.17E+07

1.18E+07

1.19E+07

Default Current-1%

Current-2%

Current-3%

Current-4%

Current-5%

Current-6%

Current-7%

Current-8%

Current-9%

Current-10%

nu-m

u/cm

^2/1

0^21

PO

T

-3%

0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 %

Effects of Horn1 current drop

Flux at Super-K

Peak Energy at ND #2 vs. Horn 1 Current Drop

1.2

1.21

1.22

1.23

1.24

1.25

1.26

1.27

1.28

1.29

1.3

1.31

Default Current-1%

Current-2%

Current-3%

Current-4%

Current-5%

Current-6%

Current-7%

Current-8%

Current-9%

Current-10%

GeV

-3%

0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 %

On-axis Peak Energy

Peak Energy at ND#5 vs. Horn 1 Current Drop

0.577

0.578

0.579

0.58

0.581

0.582

0.583

0.584

0.585

0.586

0.587

Default Current-1%

Current-2%

Current-3%

Current-4%

Current-5%

Current-6%

Current-7%

Current-8%

Current-9%

Current-10%

GeV

-0.5%

0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 %

Off-axis Peak Energy

1st horn and 3rd horn• Design and production of

prototype is on going toward the current operation test.

1st horn –prototype-

Design of the 1st horn peripherals

• Done by BARTOSZEK Engineering– Water seal (EVAC, helicoflex)– Water pipe– Auxiliary drain – Galvanic corrosion– Stripline heat load– etc. etc. etc.

• Production of them and assembling was contracted and to be completed at March.

Striplines locate far from horn body to reduce heat load from radiation

Setup for the test operation.

Striplines are extended downward for the test.

Water supply pipes are bent to absorb oscillation.

Water Nozzle attachment

-water tightness, insulation and galvanic corrosion-

Ceramic disk to insulate outer-conductor and water-pipes

Outer-conductorNozzle head

Aluminum knife-edge seal for water seal

Helicoflex seal

Stainless flange

Stripline

Stress w/ Lorenz force

9.3MPa

Forced He cooling is necessary to cool heat load from radiation.

Clamp to resist the Lorenz force is designed not to prevent He flow.

3rd horn –prototype-

• Outer-conductor contracted• Ceramic ring (1430mm!) contracted

Items other than horns

Water system pumping up 7m in ultra-high radiation environment -two options-

Self priming canned motor pump

7m

Ejector pump

Test will be done soon with canned motor pump option.

Support module

Here, we will have remote connection mech. for support, pipes and striplines.

75mm thick plate

Pipes and supporting shafts go through this plate.

Rigidity is the issue to achieve 1mm alignment

FEM analysis by S. Koike

Distortion is <0.3mm.

(Tolerance of the horn alignment is 1mm.)

Strong enough for earthquakes and (unexpected) 2-points crane hanging.

Radiation level calculation by Y. Oyama.-> not fully satisfactory but maybe acceptable.

We plan to make prototype in next FY.

Support module Alignment mech.

When the module installed remotely by crane, it can positioned automatically while absorbing manufacturing errors.

Kinematic mount on leveling block on xy-stage.

X,Y,Z position can be adjusted with freedoms to absorb manufacturing errors.

Dummy load(4ton)

It works well!

20 40 20

20 20 20

( )バスバー ホーン側

)バスバー（支持モジュール側

セラミックディスク

M16でボルト締め

セラミックチューブ

遠隔着脱部用絶縁セラミックディスク

1000

83.5 83.5

Stripline remote connection

Hot Lab.

Lift table

It must be controlled remotely.

On the lift table, there are x and y stages.

Remote disconnection/connection from this level

Summary• Schedule

– Continue Design and R&D in FY2006• Current operation test, support module,

remote handling etc. etc.

– Produce everything in FY2007– Installation in FY2008

内部導体：納入済み

外部導体 :納入済み

セラミックスリング :納入済み

セラミックスワッシャーとセラミックスボルトチューブ :納入済み

Spare support box

New horn

Alignment of (e) part of the new horn will be done at the Dock using a spare support box, on which alignment of (a) and (c) are already done.

We assume that it will be valid with the existing support box.

Remote coupling here for easy access from the top level.

1st horn and 2nd horn3rd horn

(a)

(b)

(c)(d)

(e)

Only (b) has an re-adjustable mechanism.

Other parts will be fixed once it is adjusted.

(a) and (c) : correct manufacturing error of the support box.

(b) correct target station He chamber distortion.

(d) guide mechanism between the support box and horn frame.

(e) correct manufacturing error of the horn frame.