DSG - HDice › div_dept › physics_division › dsg › ...DSG plays significant role in developing and maintaining HDice Instrumentation and Controls System Some select examples

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DSG - HDice

Tyler Lemon

Detector Support Group

June 3, 2020

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Contents


DSG plays significant role in developing and maintaining

HDice Instrumentation and Controls System

Some select examples of work done in design, fabrication, installation,

debugging, and testing are presented in this talk.

• Hardware contributions– Nuclear Magnetic Resonance (NMR) racks

– RF cables

– RF Attenuation & Distribution Box

– Oxford Intelligent Power Supplies (iPS)

– Stanford Research Systems SR844 Lock-In Amplifier

– CAENels Current Transducer Box (CT-Box)

• Software contributions– Pump Cart cRIO and Intelligent Gas Handler (IGH) Cryogenics Controller

– Rotation of Target Polarization (RTP) program

– Fast Resonance Scan (FRS) program

– CT-Box

– NMR program

– Frequency-Swept NMR program

3Detector Support Group

HARDWARE

CONTRIBUTIONS

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NMR Racks


• Assembled two racks that

house NMR measurement

equipment

– Racks are duplicates except

for CT-Box in Rack #1

• Designed, programmed,

tested, built, or procured all

components in racks

• Used for programs:– NMR

– FRS

– fsNMR

Rack #1Rack #2 CT-Box

RF Attenuation &

Distribution Box

Signal Generators

RF Amplifiers

Computer monitors

Oxford Power Supplies

Lock-in Amplifiers

RF cables

5

RF Cables


• Researched and procured semi-flexible Molex Temp-Flex air-core RF cable– Low loss: ~0.75 dB/foot

– Low temperature variation: < 500 ppm phase shift for –65°C – 80°C

• Designed and fabricated brass adapter sleeve to solder SMA, BNC, and N-type connectors to cable

• Fabricated cables

Top: Diagram of new RF cable

Middle: RF cable with BNC connector

Bottom: RF cable with SMA connector

Brass adapter

sleeve developed

by DSG

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RF Attenuation & Distribution Box


Interior of boxFront panel of box

• Attenuates and routes RF signals– 0 dB to -63 dB attenuation range

• Three units designed, built, and tested– Added screen to display settings

– Designed DAQ modules’ interface for

component-ID key reading Identifies cable types used in rack

• DSG Notes 2018-10, 2019-03


– FRS

– fsNMR

https://www.jlab.org/div_dept/physics_division/dsg/notes/2018-10%20HDice%20RF%20attenuation%20and%20switching%20unit.pdfhttps://www.jlab.org/div_dept/physics_division/dsg/notes/2019-03%20Attenuation%20Tests%20of%20the%20HDice%20RF%20Attenuation%20and%20Switching%20Unit.pdf

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RF Attenuation & Distribution Box RF Signal Path


Front RF

output

Front RF

input

Lock-in Amplifier

reference output

Rear RF

output

Rear RF input

RF dump

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Oxford Intelligent Power Supplies


• Provides current to IBC and Production

Dewar superconducting magnets

• Two versions used

– IPS 120-10: Maximum output: ±120 A, ±10 V

GPIB communication interface

No longer available

– Mercury iPS

Maximum output: ±120 A, ±10 Vo Main and secondary configuration needed

to get 120 A

USB communication interface

Updated model of IPS 120-10


– RTP Mercury iPS

Top is secondary power supply. Bottom

is primary power supply.

IPS 120-10

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Oxford Mercury iPS Testing


• Mercury iPS features– Stable bi-polar power supply

– Current precision ≤ 0.003%

– Designed for superconducting magnets

– Built-in quench protection– Automatically opens internal switch to

dissipate current through internal, high-

power resistor if quench detected

• Developed – Drivers

– Wrote LabVIEW code for calibration

• Tested power supplies

• DSG Note 2016-10 Plot of set current vs. mean measured current

https://www.jlab.org/div_dept/physics_division/dsg/notes/2016-010%20Set%20and%20readback%20test%20of%20the%20mercury%20ips%20power%20supply%20for%20hdice.pdf

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Stanford Research Systems SR844 Lock-In Amplifier


• Measures nanovolt-level AC signals of specific frequency and phase– Frequency and phase determined by reference frequency input

• 25 kHz – 200 MHz frequency range• GPIB communication to rack PC• Developed LabVIEW interface to lock-in amplifier for all NMR

programs• Used for programs:

– NMR – FRS – FsNMR

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CAENels CT-Box Current Shunt


• Researched and procured new product by CAENels– ± 150 A range

– 24-bit ADC current resolution

– < 0.005% current accuracy

– 1 Hz – 100 KHz sampling frequency in 10 µs steps (oscilloscope mode)

– Output TTL triggering

– Local current monitoring and status

• New product Issues– Firmware errors

– Lack of documentation on software protocols

– Not shipped with software we could use

– Required extensive development of library of ~60 LabVIEW

instrument device drivers

• Resolved all issues

• Developed trigger interface

• Developd LabVIEW DAQ code– Used DSG device driver library to test CT-Box

• DSG Notes 2017-03, 2016-08, 2018-14, 2018-26

• Used for NMR program

Transducer head

Controller

https://www.jlab.org/div_dept/physics_division/dsg/notes/2017-03%20Noise%20Test%20of%20the%20CAENels%20Current%20Transducer%20BOX.pdfhttps://www.jlab.org/div_dept/physics_division/dsg/notes/2016-008%20Calibration%20Test%20of%20the%20HDice%20CAENels%20CT-Box.pdfhttps://www.jlab.org/div_dept/physics_division/dsg/notes/2018-14%20CAENels%20CT-Box%20Current%20Measurement%20System%20for%20HDice.pdfhttps://www.jlab.org/div_dept/physics_division/dsg/notes/2018-26%20HDice%20CAENels%20CT-Box%20Current%20Measurement%20System%20Device%20Drivers.pdf

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Synchronization of CT-box with Lock-in Amplifier


• Synchronization incorporated in

NMR program– Provides independent and precise

( < 0.005% for I > 25 A) current

measurement

DSG Note 2016-08

• Current measurements synchronized

with lock-in amplifier measurements– CT-Box maximizes number of

measurements for variable NMR sweep

lengths

Up to 16,000 measurementso Limited by lock-in amplifier memory

– Stores measurements in NMR data filesPlot of difference between set current and measured current

https://www.jlab.org/div_dept/physics_division/dsg/notes/2016-008%20Calibration%20Test%20of%20the%20HDice%20CAENels%20CT-Box.pdf

13Detector Support Group

SOFTWARE

CONTRIBUTIONS

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Pump Cart & Intelligent Gas Handler (IGH) Cryogenics Controller


• Controls nitrogen and helium for In-Beam Cryostat (IBC)– IBC houses polarized target for

use in beam

• Replaced and tested cRIO

• Debugged overheating and malfunctioning IGH cryogenics controller

• Updated controls program

• Tested system

Liquid helium

tank

Peter Bonneau working on pump cart cRIO program

Turbo pumps

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Rotation of Target Polarization


• LabVIEW program controls two Oxford Mercury iPS power supplies to

change target polarization from spin parallel to beam to spin anti-parallel

– Supplies provide current to transverse magnet coil (B ⊥ to beam axis, max B = 0.075 T and to axial magnet coil (B beam axis, max B = 1.0 T)

• DSG Note 2016-10

Schematic of ramp profile of RTP program.

T1 (typically 10 s), T2 (15 s), T3 (15 s), and T4 (10 s) are delay/wait times in program.

R1 (typically 3 A/min), R2 (9 A/min), R3 (3 A/min), R4 (9 A/min), and R5 (3 A/min) are ramp rates of magnets

https://www.jlab.org/div_dept/physics_division/dsg/notes/2016-010%20Set%20and%20readback%20test%20of%20the%20mercury%20ips%20power%20supply%20for%20hdice.pdf

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Fast Resonance Scanner Program


• Sweeps RF frequency (50 kHz – 40 MHz) at constant B ~1.3 T

• Determines RF parameters for setting up NMR run conditions and calibration constants

• Incorporated into LabVIEW NMR program fileResonance peak at 2857 KHz

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NMR Program


• Sweeps magnetic field at a constant RF frequency, ~2.8 MHz

– E.g. Production Dewar 1: Field swept from 3150 G to 2850 G and back to 3150 G

• Reads X- and Y-component of NMR signal from lock-in amplifier

– Used in offline analysis to calculate target polarization

• Developed code capabilities

– Vary magnetic field ramp and wait times

– Vary field ranges (original range was fixed at 300 G)

– Average data for a given frequency

– Display and log averaged result

– Run scans with positive and negative current

– Execute in synchronization mode with CT-Box Synchronizes lock-in amplifier RF signal acquisition with CT-Box current acquisition

– Monitor temperature and liquid helium level

• DSG Note 2017-02, 2018-24

https://www.jlab.org/div_dept/physics_division/dsg/notes/2017-02%20NMR%20programs%20for%20HDice%20targets.pdfhttps://www.jlab.org/div_dept/physics_division/dsg/notes/2018-24%20Noise%20Level%20of%20the%20HDice%20NMR%20Field%20Sweep.pdf

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NMR Program


Green is data

from current

cycle while

field is

ramping

down

Red is

averaged data

from

previous

cycles

White is data

from current

cycle while

field is

ramping up

Magnetic

field reading

Lock-in

Amplifier Y

data

Lock-in

Amplifier X

data

Note: Y data is on

different y-axis than

X, hense the

"smoothness" of

the Y data

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Frequency-Swept NMR


• Frequency-swept NMR (fsNMR) program was developed– In Upgrade Injector Test Facility (UITF), changing field around target

can cause it to lose polarization

– Original NMR program holds lock-in amplifier reference signal

constant while varying magnetic field around target

– fsNMR program holds magnetic field constant while sweeping

frequency of lock-in amplifier reference signal

• DSG Note 2020-14

https://www.jlab.org/div_dept/physics_division/dsg/notes/2020-14%20Frequency-Swept%20Nuclear%20Magnetic%20Resonance%20Program%20for%20HDice.pdf

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fsNMR Features


• Based on FRS program

• Abilities added:

– Run multiple sweeps and average results

– Read out lock-in amplifier signal's X and Y components data Previously only read out lock-in amplifier's amplitude and phase data

– Use a previous run's data as background data Background subtracted from new data; new data manipulated to be on same

scale as background data

Verify that program settings when background data was acquired match current

run

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fsNMR LabVIEW Front Panel


Amplitude

Phase

X

Y

Red data is

averaged data from

preceding cycles

White data is new

data for current

cycles

Attenuator setpoint Number of cycles to runFrequency settings

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Example fsNMR Data


Data at largest

resonance peak

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fsNMR Scaling to Largest Background Signal


• Goal: lower effects of system noise on data and put new data on

same scale as background data

• Background data is averaged data from a previous background run

• Steps to scale:

– Subtract background data from new data

– For each frequency, f: scale(f) = data(f) × [MAX(bkg)/bkg(f)]

scale(f): scaled data point for frequency f

data(f): new data point for frequency f

MAX(bkg): absolute maximum of background data

bkg(f): background data point for frequency f

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Example of fsNMR Scaling

Using Simulated Background


1

43

2

1. Acquire background data

2. Acquire raw data

3. Subtract background from raw data

4. Scale background-subtracted data to background data

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Future plans for fsNMR Code


• Planned new software features

– Accept user input for attenuator power to be used during cycles

– Read in and use power setting from background data settings

file, if background scaling is to be used

– Ability to manually scale y-axis on plots

– Ability to fix delay between consecutive cycles

– Ability to log raw data from lock-in amplifier in addition to

background normalized data

– Log cycles as they complete rather than when program finishes

successfully

• Implement sensor logging into fsNMR program

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Conclusion


• DSG staff (Mary Ann, Mindy, Aaron, Brian, Marc, Pablo,

Peter (lead), and Tyler) deeply involved with various aspects

the HDice project

• DSG plays a major and a significant role in the

development and maintanence of the HDice

Instrumentation and Controls System

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Backup


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RF Cable Fabrication Process for N-Type Connector


1. Strip cable to center conductor

2. Strip cable section to dielectric tube

3. Strip cable section to outer braided shield

4. Affix connector center pin

5. Slip adapter sleeve over cable

6. Affix N-type connector

7. Insert adapter sleeve into connector end

8. Solder adapter sleeve to outer braided shield

9. Cover cable-connector joint with heat shrink

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2

3

4

5

6

7

8

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RF Attenuation & Distribution Box Schematic


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Rotation of Target Polarization Diagram


+I

-I

R5

Ending = Starting (-A, -T)

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DSG - HDice › div_dept › physics_division › dsg › ...DSG plays significant role in developing and maintaining HDice Instrumentation and Controls System Some select examples