# --Kicker System Specification was approved in January 2001 (see below)

Decrease in magnet length increases voltage and current

#  Increase in magnet vertical aperture increases voltage and current

**Accelerator Physics Specifications**

Kick Angle (120 Gev Protons) 553 µrad, to radial inside of MI, nominal

Magnet Vacuum Flange Location 1.687 m DS of center of Q602 in Main
Injector

(Requires moving horizontal Schottky, transverse wideband detector, DCCT
and pinger. Above includes transition piece)

Physical and field aperture 33 mm V x 81 mm H elliptical shape, minimum
clear aperture

Field Rise Time (1% to 99%) 1.30 µs maximum (588 -- 519 = 69 buckets @
120 Gev)

Field Flattop time 9.78 µs minimum (6 x 84 + 5 x 3 = 519 buckets @ 120
Gev)

Field Fall time NA

Flattop during pulse +/- 1%

Flattop pulse to pulse +/- 1%

**Mechanical Requirements (Derived from Physics Specifications and Other
constraints)**

Physical beam line space 4.72 m upstream magnet flange to downstream
magnet flange

(Does NOT include ion pumps, transition pieces or bellows. Additional
0.44 m are required for transitions and bellows)

Vacuum \< 10^-7^ Torr, 6\" Conflat flange, install bellows down stream
end,

> new 300 l/s pump and move existing 300 l/s pump downstream

Copy of MI-52 Kicker Magnet 9510--ME--359987 ( x 2 )

Power Supply Location MI-60 South Power Supply Room

Water cooling required for magnet 1200 W total (600 W / magnet, 300 W /
load)

**Electrical Requirements (Derived from Physics Specifications and Other
constraints)**

Total nominal integrated field 2.24 kG-m ( 2250 A/magnet, 2.0 m magnetic
length)

Maximum integrated field (120%) 2.69 kG-m ( 2660 A/magnet, 600 ns
propagation time)

(Above integrated field numbers include the 2.6% electric field kick)

Pulse Forming Network Length 10.9 µs minimum (=9.78 µs + 0.60 µs + 0.50
µs )

MI reset to transfer/next MI reset 1.25 seconds/1.83 seconds

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Chris Jensen Terry Anderson Nancy Grossman Peter Lucas Shekhar Mishra

(EE) (ME) (L3M Power Supply) (L3M Magnet) (MI Dept Head)

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height="5.9534722222222225in"}

![](media/image2.pct){width="8.990972222222222in"
height="5.9534722222222225in"}

--Magnet vacuum chamber problems have developed that will change
implementation considerably

-- Two remaining vacuum chambers were sent for vacuum flanging to
Ceramaseal (Jan 2001)

• One was broken by vendor and is now too short (March 2001)

• Other was damaged in shipping and needs rework. May required
re-flanging (May 2001)

• Two are required for project completion

-- The original vacuum chamber manufacturer, Coors, has declined to make
additional copies

• Originally no bid July 2000 because of low yield on last order (1995).
Coors goes public, CoorsTek

• Discussions were held with the CoorsTek to encourage them to bid at
some price

• Subsequently the ceramic firing kiln broke. We discussed repair of
kiln (Jan 2001)

• A high level representative indicated CoorsTek might fix the furnace

• CoorsTek no bid (along with 5 additional vendors) in June 2001

• CoorsTek dismanteled broken kiln

• CoorsTek is interested in cost sharing to rebuild kiln (June 2001)

• Mech Support estimate 350k\$ for new kiln of adequate size for our
vacuum chamber

• Existing ceramic chambers will be retained as spares for existing
systems (8 long magnets in MI)

-- Mechanical Support department is investigating alternative materials
and manufacturers for long chambers

--"Baseline" design is in a rapid state of flux

-   Controls for power supply were started early because of initial
    schedule and lack of mech. engineer/designer

NIM bin based controls system. Modules are copies of existing kicker
controls for MI

• Some minor changes in power supply control module for NuMI
requirements

Modules are assembled and installed in MI-60 Service Building

Auxiliary power supplies are installed in MI-60 Service Building

Design of cables between modules and outside world has been waiting for
design time.

Design of controls also has to incorporate new load and/or magnet
temperature control system.

Two special cables have been installed between MI-52 and MI-60 for fast
inhibit & permit signals

--Thyratron and Tube Enclosure

The CX1592 from Marconi Applied Technologies (née EEV) was selected in
consultation with them

• To get long life from thyratron manufacturer suggests use of double
triggering, new minor task

The mechanical design of the tube enclosure was started with a
designer/drafter in February 2001

The mechanical and electrical design of the tube enclosure is 95%
complete

The mechanical and electrical drawings of the tube enclosure are 75%
complete

Manufacturing of various components has begun.

All the components of the tube enclosure should be useable regardless of
most changes in requirements

The new tube enclosure incorporates these changes over existing MI-52
enclosure

• Add capability for double triggering

• Change direction of output cables to reduce footprint of supply

• Reduce inductance of enclosure to reduce rise time and improve
performance

• Change the high current connections for lower current density and
better fit

Monitoring of the CX1592 in use at MI-52 has begun to determine pre-fire
rates of thyratron

Pre-fire rates at 45 kV are 0 in approximately 10\^6 pulses. This rate
is highly voltage dependant.

--Pulse Forming Network and Enclosure

Only preliminary design work has been done so far.

Mechanical cartoon of enclosure is done showing what features are
required.

Specifications for the capacitors were done and capacitors were under
contract

Capacitor contract was cancelled due to non--performance. Now
specifications may change too.

Travel to TRIUMF to look at PFN for LHC Injection Kicker with similar
performance requirements

Inspection of MI-52 PFN has shown some problems which must be addressed

• High current connections to thyratron and between inductors show
damage after 10\^6 pulses

• There is no coupling between cells which results in slow rise time

Design of PFN to have ripple period close to magnet transit time for
best performance

Design of PFN has to meet not only electrical constraints, but also
physical size and cable routing limits

-- Charging Power Supply

Specification was written but now must be changed

Operating voltage up to 50 kV is standard for regulation and average
power required

Existing specification required 55 kV maximum voltage to allow for 120%
of nominal operation

Regulation achieved with current supply and load temperature variations
was measured.

• Over several hours, when load temperature is stable, regulation is
better than +/- 0.25%

• Over sixteen hours, when load temperature is somewhat stable,
regulation is worse than +/- 1%

• More measurements are being made to determine the cause of the larger
variations.

-- Magnet (This is covered under a separate review but also relevant
here )

As mentioned earlier there is no longer a commercial manufacturer of 86"
long ceramic vacuum chamber

Investigations into glass (high purity boro-silicate) and other
materials will continue in the near term

A drop dead date has to be determined to go to 60" long ceramic
chambers.

The dielectric fluid used currently has degraded in the MI kickers.

• A solution has been installed in MI to determine its long term
effectiveness

There is considerable tunnel temperature variation near Q602, \~ +/- 5F,
due to the major vehicle access ?.

• The extremes at Q520 are similar, but the variation is seasonal, not
daily

• Magnet temperature variations lead to an impedance mismatch and a step
in the flattop

• Capacitance has temperature coefficient of approximately --0.33%/C

-- Magnet Load (This is also covered under separate review but also
relevant here)

The load resistors for NuMI extraction kicker have a much higher average
power dissipation

The higher dissipation (1.5 times MI-10 load) will result in higher
temperature extremes

• The load resistors have a temperature coefficient of approximately
--0.1%/C

• Change in resistance is equivalent to mismatch step in flattop and to
power supply variation

• There is a reliability problem with the high power loads at MI-10 that
is related to the coolant

and to the radiation. The NuMI kicker should not have high radiation
losses.

--Installation

Cable pulls for all but the high voltage cable are complete.

• High voltage cable installation in 2003

All cables are purchased (unless design changes substantially)

Pulse forming network and switch enclosure will be assembled in tech
area and delivered to MI-60

Installation in 2004

Pre-fire testing will start when the tube enclosure is completed.

• Pre-fire testing will start at F-17 service building where a test
system is currently in use

Power supply capable of 75 kV

High power loads for 12.5 Ohm system

• Pre-fire testing will move to MI-60 when control system there is
complete (2003?)

Commissioning of kicker controls will be done then

-- Documentation

System specification was written. Implementation details likely to
change substantially

Charging power supply specification is written but likely to change

Pulse forming network capacitor specification is written but likely to
change

End of line diode specification is written and done

LOTO procedure and safety analysis is still required

Electrical and mechanical drawing package needed for documentation (10%
complete)

--Simulations and Calculations

Simplified electrical model of PFN needs work to verify model with
existing performance of MI-52 system.

• MI-52 PFN is now disconnected from service and may be directly
measured.

Detailed model of magnet and load required to model system performance

• Prototype magnet is available to make measurements

Complete simulation of new PFN and magnet needs to be done to verify
system performance

-- Manpower

Electrical Engineer/Designer

• Chris Jensen

Electrical Technician for controls and PFN assembly

• Dirong Chen

• Some other help for PFN assembly from EE Support possible

Mechanical Technician

• PFN assembly ?

• Magnet assembly ?

Mechanical Engineering/Review

• Power Supply Mechanical Design ?

Mechanical Drafting

• Tim Hamerla, currently time sharing with other projects

Plans for Remainder of Calender Year

-- Finish design, detail and fabrication of thyratron enclosure

-- Begin long term pre-fire and pulse testing of thyratron

-- Order new PFN capacitors

-- Design PFN inductor

-- Design PFN mechanical enclosure

Remaining Concerns

The pre-fire rate of the thyratron is extremely sensitive to voltage and
a very low pre-fire rate is desired

Some things can be deferred for 18 months

• Thyratron and spare.

• PFN enclosure

• PFN inductors

• Charging power supply

Some things need to be ordered before

• Order PFN capacitors as soon as possible

• Prototype inductors after capacitors have been inspected and measured

The charging power supply may be relatively expensive because of
increased voltage and power.

Something in specification will change due to some unforeseen
operational requirement