JB Undergraduate Research Progress

This page gives an overview of the work I have done under the supervision of Dr. Richard Jones from May 2013 to the present time.

Finalizing summer work

I worked in the lab as a student worker during the summer of 2013. My day to day summer log can be found here. I spent my time working on a proposal for a chilled water line for the servers in P403. I finalized this document in the beginning of the Fall 2013 semester. It can be found here.

Familiarizing myself with the active collimator

When I first gained access to the active collimator, I took it apart in order to understand its structure. Below are pictures that I took upon its disassembly.

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  A shot of the collimator's face plate. The four screws that are visible along the vertical of the face plate in this picture secure the tungsten pin cushions to the white insulating cup.

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  A picture of the inside of the active collimator. The tungsten pin cushions are secured onto the boron-nitride insulating cup. Another four tungsten pin cushions will be installed; see the exploded view two pictures to the right.

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  The grounded cup, completing the Faraday cage structure of the collimator.

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  A diagram that labels the components of the active collimator. Credit to Igor Senderovich.

I read Igor Senderovich's PhD thesis very carefully in order to understand the active collimator's purpose and how it works. This project is largely based on Senderovich's work from his time under Dr. Jones's supervision. The active collimator has been quality assured by Alex Barnes, James McIntyre, and Dr. Jones. A detailed PowerPoint regarding the use of the active collimator in the GlueX experiment was written by Dr. Jones, Igor Senderovich, and Ann Marie Carroll for an APS/DNP meeting in October of 2012.

Data Acquisition

My research thus far has been focused on examining the electronic properties of the active collimator. I spent a few weeks working on capturing waveforms with a Tektronix TDS 2024 Digital Storage Oscilloscope by tapping the pin cushions with a piece of metal that I was holding in order to build up a charge on the cushion. I connected each of the tungsten pin cushions within the active collimator to cables with an RF coaxial adapter input which was connected to the face plate and a BNC output which was connected to a PMT-5R amplifier. I used a F-100PS 15 Volt DC Power Supply to power the amplifiers. However, I did not have control over the amplifier's gain setting with this setup.

Igor developed a data acquisition LabView program for the active collimator. The program allows the user to vary the gain setting on the amplifiers from 10^6 to 10^12 in powers of ten, record the potential difference across each of the tungsten pin cushions at a frequency of about 800 data points per second, and calculate Fourier transforms on the received signals. The program is run on a PC that Alex Barnes and I built which contains a data acquisition card. Below are pictures of the pieces of equipment used for data acquisition.

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  A PMT-5R amplifier. The signal from each pin cushion in the active collimator passes through one of these before it is sent to the PC.

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  The power supply used to power the amplifiers.

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  The terminal board that is used in collaboration with the data acquisition card installed in the PC.

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  The active collimator station in Dr. Jones's lab.

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  A close-up view of the active collimator connected to the amplifiers.

Trip to JLab

I traveled to Jefferson Lab in Newport News, Virginia from January 4th to January 15th during my 2014 winter break. My day to day log for my trip to Jefferson Lab can be found here (search "JLab trip"). I have also created a travel expenses spreadsheet and an inventory spreadsheet.

Tour of Hall D

On January 10th, Sascha Somov took me to the accelerator site for a tour of the Hall D facility. Below are some pictures I took during the tour. Note that the pictures follow direction the photon beamline; each successive picture is downstream from the previous picture.

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The actcol-station is set up in F117 of the CEBAF building at Jefferson Lab. I have created a wiki page that teaches a user how to operate the station.

Data Analysis

I have been using the C++ based program ROOT in order to analyze the data obtained from the active collimator.