10/3/2003Andreas Jansson - Tevatron IPM review1 Tevatron IPM Proposed design

10/3/2003 Andreas Jansson - Tevatron IPM review 1

Tevatron IPM

Proposed design


Overview

• Space requirements, location

• Detector design

• DAQ system

• Timing and software

• Commissioning, calibration and maintenance


Space requirements

• Two IPMs can be fitted in about 3.25 m

• Additional space may be required for calibration device (e.g. OTR screen).

stand/support


Vacuum system

• Incorporate a controllable leak (N2) to increase gas pressure, pumps to localize the ‘pressure bump’ and sector valves for maintenance access.

ipm ipm

ion pumpion pump

sector valve sector valve

variable leakvalve


Magnet stands

• Motorized stands are needed to align detector with the beam (due to large aspect ratio of anode strips).

• These can also be used to center the detector on the beam orbit.

• Only the vacuum can with detector needs to be moved, the magnets can be fixed.


Location

• E0 has sufficient free space and is close to flying wires, scrapers, new schottkies etc

• Proton/pbar time separation 110-150 ns

flying wiresE0 center


Radiation measurements

• Radiation levels at 4-5 feet is less than 0.5 rads/hour

• With the current 60% duty cycle, that gives an annual dose of 2500 rads (8 years for QIE).

1 2 3 4 5Distance from beamfeet

5

10

15

20

noitaidaRlevelsdar

h


Internal detector design


Anode board and FE cabling

• ¼ mm strip spacing. • Flex circuit to provide

matched transmission line to vacuum interface.

• 50 pin D-type feedthrus.

• Shielded twisted pair cable on the outside.


Block diagram/data flow chart

seri

aliz

er 16 serial links

(optical fiber)~1.6 Gbits/s/link~23 Gbit/s total

Pro

ton

mkr

Ano

de s

tirp

sig

nals

(~

128)

16

Proton revolution marker

Kwame Vince, Mark et al

PCI busDMA xferBurst mode~1 Gbit/s

Pbar revolution marker

QIE

QIE

(8 Q

IEs)

opti

cal d

rive

r

Fas

t (w

ide)

mem

ory

FP

GA Data

Commands:•Start/stop DAQ•Readout data

QIE

res

et/r

eset

Fanout Injection markerTiming generator Injection event

(UCD+RFT?)

in tunnel in upstairs PC

GPIB (?)controller

To power supplies

PC

I B

US

?

Header gen.

15 M

Hz

Pba

r m

krIn

ject

ion

mkr

15 MHz clock

QIE reset


396 ns (21 buckets)

p/pbar separation

RF

2/7

1/7

Timing

( )

injectioncollision


Header timing info

• Proton marker bit (marks sample with first proton bunch).

• Pbar marker bit (marks sample with first pbar bunch).

• Injection marker bit (marks first turn at injection).

• QIE mode and cap ID# (4 bits)


Software

• Card driver to be provided by CD

• Low level code to transfer and sort data.

• High level code to analyze (fit) data.

• Modify existing IPM LabView program for top level part (at least initially). Need to write new low-level code.


Commissioning

• The system timing needs to be adjusted with beam, to compensate for cable delays etc.

• Involves adjusting phase of sample clock, plus delays of proton, pbar, and injection marker (to correct for location in ring).

• Will be done empirically.


Calibration

• A number of cross checks can be performed– Monitor average signal to detect saturation.– Vary B-field to verify electron focusing.– Use internal electron source and/or move

detector wrt beam to verify MCP gain uniformity.

– Detect parasitic coupling by turning off MCP, clearing voltage etc.


Absolute calibration

• In the end, the only way to do an absolute calibration is to compare to another instrument.

• Install a simple profile detector next to IPM.– OTR screen would be suitable, and there is

interest from the Instrumentation group to build one for the Tevatron.


Maintenance

• Monitor MCP gain uniformity and change plates periodically

• Monitor QIE cards (current draw) and replace if needed.– Single dead channels is not a disaster, but a

dead card may be a problem.

• Regular infrastructure (water, magnets, …)


Summary

• We believe we have a sound basic design– Need to build and test DAQ system chain (QIE

card, buffer card, timing and fanout)– Need to build and test detector unit (including

vacuum can) to test RF properties • suppression of parasitic signals

• longitudinal impedance.

Documents

10/3/2003Andreas Jansson - Tevatron IPM review1 Tevatron IPM Proposed design