Cherie Landa

FALL 2016

Captain's Log, stardate 9/1/16

PHYSICS: comparison of Rutherford's gold foil experiment (throwing alpha particles at a nucleus) to electron-proton collisions; since the particle bounces back it must have HIT something very strong (like a ball bouncing off a wall); in the case of electrons bouncing off protons, it is hitting QUARKS.

COMPUTING: okay. so. Linux.

it's basically just File Explorer (windows) or Finder (Mac)

NAVIGATION:

pwd print working directory ("where am i???")

cd change directory ("take me to _____")

ls list files and directories ("whats in here?")

MANIPULATING FILES:

cp copy files and directories

mv more or rename files or directories

rm remove files and directories (are you sure you want to use this? would you bet your mother's life on it? this is the country from whose bourne no traveller returns. THERE IS NO UNDO FOR THIS. use wisely.)

mkdir make directories

EMACS:

like word, but very very basic. pretty much like the note app on most phones, except emacs can tell if you're writing code if you tell it that you are.

to make a new emacs file type:

emacs -nw filename.txt

(the .txt make it a plain text file; if you want a linux script it's be .tcsh, a c++ script would be .cpp, etc.)

SPRING 2017

Captain's Log, stardate 2/7/17

Cat and I met with Professor Alberto to discuss what we will be working with--measuring the decay and dirtying of the plastic scintillators in the CMS detector due to radiation. They seem to be going bad faster than expected--need to find a way to keep them clear for longer 'cause they're super expensive and annoying to replace.

Captain's Log, stardate 2/9/17

RESEARCH:

http://www.particleadventure.org/

very cute site, explains a lot of things: IF YOU ARE AT ALL CONFUSED DURING THE FIRST SEMESTER OF THIS CLASS OR ARE JUST A CURIOUS HUMAN BEING, CHECK THIS LINK OUT IT'S GREAT.

http://pdg.lbl.gov/2012/reviews/rpp2012-rev-passage-particles-matter.pdf

30.2.7 is especially important sections for our research

http://iopscience.iop.org/1748-0221/3/08/S08004

5.1, 5.2, 5.3

https://twiki.cern.ch/twiki/bin/view/CMS/UMDScintillatorUpgradeTesting

(can't open it)

https://twiki.cern.ch/twiki/bin/viewauth/CMS/UMDScintillatorUpgradeTesting

(can't open it)

http://cms.web.cern.ch/news/hadron-calorimeter

did you know that the brass sections of the HCAL were made from WWII Russian navy shells? it's so nice to see tools of war being used as tools of science instead of the other way around.

https://cds.cern.ch/record/357153/files/CMS_HCAL_TDR.pdf

"The Central Hadron calorimeter is a sampling calorimeter: it consists of active material inserted between copper absorber plates. The absorber plates are 5cm thick in the barrel and 8cm thick in the endcap. The active elements of the entire central hadron calorimeter are 4mm thick plastic scintillator tiles read out using wavelength-shifting (WLS) plastic fibers.The barrel hadron calorimeter is about 79 cm deep, which at =0 is 5.15 nuclear interaction lengths (λ) in thickness"

"1.3.2 Radiation damage

The hostile radiation environment implies that a lot of attention has to be devoted to selecting sufficiently radiation hard technologies. A significant part of LHC related R&D work has in fact concentrated on radiation hardness studies of detectors and electronics. Silicon devices will be used in essentially all parts of CMS, either as electronic chips, as charged particle detectors or as photodiodes. Similar dose-related damage effects have been reported for organic and inorganic scintillators, i.e. the PbWO4 crystals of the CMS electromagnetic calorimeter and the plastic scintillators of the CMS central hadron calorimeter. In these cases the light transmission degrades due to the generation of color centers by the ionization (i.e. the plastic becomes less transparent). Thus the degradation of scintillators is also a function of the radiation dose. Although in most cases significant annealing is observed, some fraction of the damage is never recovered and the detectors continuously degrade with increasing fluence or dose. The annealing effects make radiation damage a complicated function of both time and fluence. For instance, the calibration of a calorimeter might change due to both degradation during irradiation and simultaneous improvement due to annealing. If the annealing is very fast the calorimeter response can become luminosity dependent."

"The problem of radiation damage to the plastic is most severe in the endcap (HE). In this detector, the radiation field scales approxiamtely as 1/θ3 so the region at low is less seriously affected. In the endcap region, up to , our baseline is to use SCSN81 scintillator with Y11 doped fiber and 2 longitudinal segments. In this section the dose is <0.4 Mrad"

(PRETTY MUCH ALL OF SECTION 6.2)

https://indico.cern.ch/event/367368/contributions/1783339/attachments/730363/1002130/HEPP_Proceedings_CPelwan.pdf

"With the phase two upgrade of the ATLAS detector in mind, this project, accompanied with various other studies done on the plastic scintillators looks to eventually find a suitable candidate for the replacement of the MBTS platics as well as the the plastic scintillators housed inside the TileCal once they have lost their efficacy. We would also have a deeper understanding of radiation damage in plastic scintillators as a whole and hopefully this knowledge would aid in the design and manufacture of a plastic scintillator that is less susceptible to radiation damage than the technology currently available."

Captain's Log, stardate 2/10/17

Went to meeting at 3:30. Discussed what we will be doing and what we will be working with and some background on the project.

Essentially three things we will be measuring for:

1) Absorption

2) Emission

3) Alpha Source

They are very precise measurements and the plastic we will be working with is very fagile; it must be handled with care and stay organized; the samples are not labeled directly and therefore need to be put back where they came from to keep everything neat.

Need to get radiation training.

Captain's Log, stardate 2/15/17

Finally gained access to CERN account again--more reading to be done:

KNOLL

Chapter 8

Chapter 9

Chapter 10

Captain's Log, stardate 2/17/17

Friday meeting with Professor Eno and Professor Alberto.

1) substrate (plastic is most effective)

2) primary

3) secondary

BENZENE

When a substrate receives a radiation dose:

1) color centers: radicals form

2) degradation (long strings split into smaller strings) and gas evolution (gas rising from it)

STOKES SHIFT: shift between wavelengths the material likes to absorb and the wavelength the material likes to emit

Plastic comes out of the detector yellow--> the radicals that have formed then pair back up, causing the plastic to become clear again

-->When the radicals form polyene instead of polystyrene, it forms a color center. This is bad.

OXYGEN decreases temporary damage, but increases permanent damage.

low dose; low radical production rate; oxygen penetrates deep

high dose; high radical production rate; oxygen is on the outside

DOSE-RATE EFFECT is derived from diffusion

Gel (caused by increased oxygen) = substantially cross-linked; radicals are much less mobile

RADICAL MIGRATION: R*O2-->RO2

temporary damage goes away as the radicals move and find good bonds; however, more permanent damage comes from the new terminations

There are more color centers at room temperature in a vacuum; keep the plastic HOT, it keeps the color centers down (since the radicals keep moving around).

Captain's Log, stardate 2/23/17

Radiation safety training:

The most important unit of measure for radiation: the BED: a banana equivalent dose.it is actually defined as 0.1 µSv.

MAIN UNITS:

1) RAD: 100 erg dose of energy

2) REM: used to describe biological damage; defined as RAD*Q=REM, where Q is the quality factor of the material

3) Rontgen (R): 1 electrostatic cm^3 of air, at STP for gamma and x rays

(1 RAD= 1 REM= 1 R)

BACKGROUND:

1) Cosmic Rays

2) Terrestrial (Rad-202)

3) Internal (C-14, K-40, H-3, etc)

4) Food & Water

5) Medical (CT Scans, etc)

BIOLOGICAL EFFECTS (on cells):

1) mutation

2) kill

3) repair

4) nothing

5) stimulate

6) super powers

ALARA: As Low As Reasonably Achievable

-time

-inverse square law

-shielding

Captain's Log, stardate 2/24/17

Friday meeting with Professor Alberto:

Need measurement training for absorption, emission, and alpha source.

Need to finish radiation safety test.

Temporary damage is still recovering. 7x7 were observed to have less light reduction than the 10x10 tiles.

Figuring out who's measuring what.

Two main sizes of tiles:

1) finger tiles (1x1x5)

2) sigma tiles

Each sample gets three measurements (emissions, alpha, absorption)

at three different temperatures: -30C, -20C, -10C

TWO MAIN PLASTICS (trying to figure out which is a better solution):

1) EJ200 blue range (clear)

- color center; absorb light instead of transporting it out as info (they absorb BLUE light so they turn yellow since they’re complimentary colors)

- Higher light output; goes bad faster

2) EJ260 green range (490nm)

- Shift to longer wavelengths; don’t creat color centers because it’s a diff wavelength

- Lower light output; goes bad slower

ELJEN: commercial scintillators ( http://www.eljentechnology.com/ )

Pi electrons: contribute to scintillation, benzene ring

read: Birks, 1964 search for PVT

NOTATION/TERMS:

PS- Polystyrene

Fluors (fluoropolymer)-

1) -Two fluors: shift wavelength to longer wavelength to match PMT (photomultiplier tube) to where the PMT is most sensitive

2) -First fluor transfers to 350nm

3) - Second shifts to 450nm (24%) more sensitive

PVT- polyvinyl toluene (structured like a ball of string, not like a lattice)

SCSN81- polystyrene based material

EJ200-SP means specially made; NOT the same as PS

3 components of the scintillator (percentage in weight):

Base (100%)
Primary fluors (1%) = P
Secondary fluors (0.01%) = X

”1X1P” coefficient is the percent; so 1X2P would be double the concentration of the primary

Thickness labels (variations T#)

àEffects of geometry and dimensions

Nominal doping- 1X1P

(nominal= standard/control)

CRF- near the beam pipe; high energy gamma source

We will be working with beta and gamma category of radiation

Captain's Log, stardate 2/28/17

Submitted radiation safety test to Bryan, waiting on official certificate, and then we can finally start taking measurements ourselves, woo!

Captain's Log, stardate 3/3/17

Observed emission measurements after Friday meeting. Learned process and how to use machine as well as program that create the graphs of the measurement. How to save the measurements and upload them.

Also, we're radiation safety certified, yay! :D

Faces of tiles are ABCD; A is the side with the notch on it, and then it goes counterclockwise to B,C, and D.

Captain's Log, stardate 3/13/17

34.3 ORGANIC SCINTILLATORS

1) Crystalline

2) Liquid

3) Plastic

->Use the ionization of charged particles; makes blue/green wavelengths of light (photons)

PLASTIC SCINTILLATORS

Densities range: 1.03-1.20 g/cm^3

Photon Yields: 1 photon per 100eV of energy deposit

For example, a 1-cm thick scintillator will yield 2x10^4 photons when traversed by an ionizing particle.

The signal produced from this interaction depends on:

1) Collection efficiency

2) Transport efficiency

3) Quantum efficiency of the photodetector

Dense ionization columns emit less light

Plastic scintillators are sensitive to proton recoils from neutrons.

34.3.1 SCINTILLATION MECHANISM

“A charged particle traversing matter leaves behind it a wake of excited molecules.

Certain types of molecules, however, will release a small fraction (≈ 3%) of this energy as optical photons.

This process, scintillation, is especially marked in those organic substances which contain aromatic rings, such as polystyrene (PS) and polyvinyltoluene (PVT).

Liquids which scintillate include toluene, xylene and pseudocumene.”

Fluorescence: photon is absorbed, excitation occurs; photon of a longer wavelength is emitted, de-excitation occurs.

FLUORS are “waveshifters” (that sounds really cool actually); they shift the light that the scintillator picks up and shift it into a more convenient wavelength.

Stokes’ Shift:” The wavelength difference between the major absorption and emission peaks is called the Stokes’ shift.” The range photon energy/wavelength where emission and absorption overlap; i.e. what fraction of the light that is emitted be re-absorbed. (We don’t want ANY reabsorption to occur. That would mess everything up). So the LARGER the Stokes’ shift the fluor possesses, the less re-absorption, the better the scintillator.

Plastic scintillator in high energy physics are made of a solution of fluors in a plastic base. This plastic base is aromatic, meaning its molecular structure is a bunch of rings.

Pretty much all plastic scintillators are made of PS or PVT; PVT-based are up to 50% brighter

PRIMARY FLUORS

Ionization in the plastic base produces UV photons with short “attenuation length”

(Google: In physics, the attenuation length or absorption length is the distance into a material when the probability has dropped to 1/e that a particle has not been absorbed.)

Dissolving a “primary fluor in a high concentration (1% by weight) base, it will produce long “attenuation lengths”

Decay time for PS is 16 ns; adding a primary fluor in high concentration can shorten the decay time, and increase the total light yield.

This fluor can’t do everything though, so we need to put in a secondary fluor (another “waveshifter”) at specific levels.

The scintillation light is captured by a “lightpipe” which is a waveshifting fluor dissolved in a nonscintillating base. The fluor must be insensitive to both ionizing radiation on Cherenkov light. A typical wavelength shifter consists of the following: an acrylic base, a single fluor to shift the light from the plastic scintillator into the blue-green spectrum, and UV absorbing additives to decrease response to Cerenkov light.

34.3.2 CAVEATS and CAUTIONS

Things that can aggravate the process:

1) Exposure to solvent vapors

2) High temperatures

3) Mechanical flexing

4) Irradiation

5) Rough handling

6) “Craze” the surface

Crazing= microcracks on the surface of the plastic caused by contact with oils, solvents, and or fingerprints.

Intensities at the 10^-4 level can last for hundreds of ns.

Light yield decreases with increasing partial pressure of oxygen.

Light yield can be changed by a magnetic field. But not all scintillators. 3% increase at 0.45 T. This is sketchy. Why?

Irradiation creates color centers; these absorb more UV and blue rather than at longer wavelengths. This becomes a reduction of light yield and attenuation length.

Radiation damage depends on:

1) Integrated dose (total energy absorbed, (mass irradiated)*(absorbed dose))

2) Dose rate (amount of radiation per unit time)

3) Atmosphere

4) Temperature

->all before, during, and after irradiation

Annealing (Google: heat (metal or glass) and allow it to cool slowly, in order to remove internal stresses and toughen it) occurs by the diffusion of atmospheric oxygen at high temperatures.

“Better red than dead” color centers are less disruptive at longer wavelengths; utilize fluors with large Stokes’ Shifts.

34.3.3 SCINTILLATING AND WAVELENGTH-SHIFTING FIBERS

WLS = wavelength shifter

SCIFI = scintillating fiber

SCIFI Calorimeters are fast, dense, radiation hard and can have “leadglass-like” resolution.

SCFI trackers can handle high rates, are radiation tolerant, but must use sensitive photodetectors because of the low photon yields at the end of a long fiber.

WLS readouts allow for a high amount of hermeticity (like, hermetically sealed?)

Typical configuration:

Fibers with a core of PS-based scintillator or WLS

Surrounded by PMMA

Make sure that the surface between the PMMA and the fiber is uniform so that everything transmits well.

The generated light transferred to the tube is 6% single-clad fiber and 10% double-clad fiber.

Minimum ionizing particleà 2000 photons; only about 200 are captured.

Attenuation length factors:

1) Re-absorption

2) Level of crystallinity of the base polymer

3) Quality of total internal reflection boundary

Captain's Log, stardate 3/15/17

Observed Alpha Source Measurements:

Make sure the GPIB::13 is OFF or at 0 before opening anything

1) Warm up the machine for 20 mins

-Strat with a reference sample, run the data and make sure that the means are within 1% of each other to make sure that things are calibrated properly

-If you’re measuring face A, the face will go in contact with the source.

2) Place the face down towards PMT, push it against the back

-make sure the source and the tube are flat

-align the purple lines with each other using the dentist tool thing

(when the line on the machine is thicker than the line on the source, align to the left)

-close everything and then cover it

-write the sample name on the whiteboard

3) After 5 mins, turn the voltage off gradually

-don’t just take the voltage all the way up or down to 1700 V, manually increment it until it gets there.

4) Oscillator

-the settings are pretty much always the same so you don’t really need to worry about it

-save file as the samplename+timestamp

5) Save files to flash drive under specified directory

-Use tree file to convert them into root files

-use simple compare python script to compare the two files

àgive mean values

-create a pdf of the files/histograms

(make sure the graphs overlap a lot/match up

6) Lower the voltage incrementally, take the sample out, and put it back where it belongs

Captain's Log, stardate 3/29/17

Working on getting keys to the room.

Working through the readings.

Captain's Log, stardate 4/4/17

Re-observed and practiced Emission measurements with Yongbin.

1) Warm up Spectrofluorometer--takes about 2 hours

2) Open FluorEssence V38 Program

Set file name to be TodaysDate_SampleName

3) Take EJ200 measurement first, side A then B then C then D

Experimental Setup

Make sure to set the sample name with the name of the face at the end (ABC or D)

Measure peaks for wavelengths 400, 350, and 285

4) Repeat for EJ260 sample

Captain's Log, stardate 4/5/17

Practiced Emission measurements with Yongbin again.

Captain's Log, stardate 4/13/17

Met with professor Belloni

Captain's Log, stardate 4/14/17

Observed Alpha Source with Ruhi

I finally got keys! Yay!

Captain's Log, stardate 4/16/17

Going through readings

Captain's Log, stardate 4/20/17

Observed alpha source with Zac

Going through readings

Captain's Log, stardate 4/26/17

Took Alpha Source measurements for 5 hours. Nonstop.

Tried creating comparison plots between mine and Zach's measurements.

Worked with emacs and python scripts.

UPDATED ALPHA SOURCE HOW TO:

1. Preparation

The first thing that must be done before all else is to make sure that the PMT has no voltage being supplied to it. To do so, check that the box labeled GPIB::13 is either completely powered off, or is at zero volts. If you open the dark box while the PMT is on, you will break the PMT and possibly harm yourself; it is also important to check at the very beginning to make sure that the machine hasn’t been running for an extended period of time. Also, check that the oscilloscope is unplugged (the green wire). Once you are ready to start warming the machine up--which takes about 20 minutes (30 for the reference sample)--you can turn on the PMT. To do so, flip the switch on GPIB::13 to on, and then incrementally increase the voltage by 100 V until you reach 1700 volts. You don’t want to go from zero volts to 1700 volts at once because you could fry the PMT.

While the machine is warming up, you can begin preparing the sample. The first sample you take should always be the reference sample, to make sure that all of your measurements will make sense (EJ200_2X_3a). Be sure to wear gloves and have a Kimtech piece of paper down before taking out the sample. Once the sample is out, select an alpha source from the drawer (P-239?), then place the sample on the source with the face you are measuring in contact with the source, in between the two pieces of tape; the side with the notch should be facing you. (Always be sure to put the key to the alpha source drawer back in the other room.) At this point, the source and sample are ready to be placed in the dark box.

2. Taking the Measurement

Once the machine has warmed up for 20 minutes, incrementally lower the voltage on GPIB::13 by 100 V until the voltage being supplied is zero. You can now open the dark box by flipping the outer sheet and whiteboard up, unlatching the door, and finally sliding the inner curtain to the side. Place the sample and the source on the lens of the PMT, with the sample on top of the lens and underneath the alpha source. You must make sure that the source and sample are as perfectly aligned and level as possible. to do so, use a mini-mirror and a flashlight to check that the purple lines on the source match up with those on the PMT. Once the source is properly aligned and leveled, close the inner curtain, close the outer door and latches, lower the outer sheet, and finally write the name of the sample, your name, and the word ON on the whiteboard, so that other people who may need the sample will know where it is. Finally, plug the oscilloscope back in, and incrementally increase the voltage to 1700 once again.

3. Recording the Measurement

First, check that the oscilloscope is running on the proper presets. Go to File/Instrument Setup/ and select the proper preset for your sample; for the reference sample, Recall preset 10; ColdConfig, and then Save. Open the Detailed Plus Fast Frame.vi program on the adjacent computer. Enter the amount of time you want to run the measurement for, which is usually 300 seconds (5 minutes). Click “Begin,” and then click the run arrow on the top toolbar. The graphing window on the program should mimic the oscilloscope.

After 5 minutes, an option so save the measurement should pop up on the computer screen. The file is then saved under following the nomenclature of the previous files, including the sample name and date. The file is then moved to the directory “AlphaSourceData” via USB. The files are then converted into root files using the "RunLists" file in Terminal on the Mac next to the main computer. Then, using the file "compareSimpleAlpha", the measurements are compared (faces A and C) and the average mean values are taken. Finally, view the graphs of the files by typing in open /tmp/filename.pdf where the filename is the sample you've selected. (Make sure the graphs line up, i.e. the measurements match up)

4. Cleaning Up

Incrementally decrease the voltage of the PMT until it is at zero. The dark box is then reopened and the alpha source and sample are removed. The sample is placed back in it’s paper label and plastic bag, and put away, and then the next sample is ready to be taken. Once all the sample measurements have been taken, the PMT is turned OFF, the samples are put away and the alpha source is put back in the drawer (the drawer is then locked). Always cover the box full of samples when it is not in use. Do not touch things without gloves on.

Captain's Log, stardate 4/27/17

Met with professor Alberto--I have more keys! Yay!

Discussed the PMT chapter and significance of Alpha Source and Emission measurements.

CHAPTER 4: RADIATION DETECTORS

Hypothetical detector is subject to some kind of radiation; focus on a single particle or quantum of radiation, like a single alpha particle. In order for the detector that the particle in=s in to respond, the radiation must undergo an interaction in which it deposits its energy.

A detector assumes that “when a quantum of this type of radiation” is present, there will be a “charge Q” that appears. This charge must be collected in the form of a signal, which is usually accomplished through an electric field within the detector.

Collection time for the signal varies from detector to detector; ion chambers take as long as a few milliseconds, whereas a semiconductor diode detector takes a few nanoseconds.

MODES OF DETECTOR OPERATION

There are three general modes of radiation detectors:

1) Pulse Mode

record each individual quantum of radiation that occurs in the detector; time interval to collect charge Q is recorded; categorized as radiation spectroscopy. Pulse counting is common as well.

3) Mean Square Voltage (MSV) Mode

When detectors are operated in pulse counting modeàpulses that exceed a certain threshold or don’t reach a certain threshold…

CHAPTER 9 PMT’s

INTRO

Convert extremely weak light output from scintillation into an electrical signal

PMT’s convert lights signals made up of only a few photons into a readable pulse without adding too much random noise to the signal

STRUCTURE OF PMT:

1) photocathode: converts the light photons into low-energy electrons

2) electron-multiplier-structure: amplifies the number of electrons; a typical scintillation pulse will give rise to 10^7-10^10 electrons, which can serve as the charge signal for the scintillation. This charge is collected at the anode or output stage.

Output pulse at the anode is proportional to the number of photoelectrons

PHOTOCATHODES

Conversion of light photons into electrons has 3 stages:

1) Absorb photon, transfer energy to an electron within the ‘photoemissive’ material

[The energy that can be transferred from photon to electron in step 1 is hv (the quantum energy for a photon). ]

2) Movement of the electron to the surface

[some of the energy is lost through electron0electron collisions]

3) Escape of the electron from the surface to the photocathode

[must be enough energy left for the electron to overcome the potential barrier caused by the interface between the material and vacuum]

Photocathodes have a long-wavelength (small v) cutoff in the red or infrared spectrum. We want the surface barrier to be as low as possible to maximize the number of escaping electrons.

For a light photon to be absorbed in a semiconductor its energy must exceed the bandgap energy (hey we learned this in chemistry!) Elevate the electron from the valence band to the conduction band. The use of negative electron affinity materials causes a much greater escape depth because it allows the electrons that have dropped to the bottom of the conduction band to escape as well.

ELECTRON MULTIPLICATION

Based on secondary electron emission. The electrons from the photocathode are accelerated and then strike the surface of an electrode, called a dynode—the energy deposited by the electron into the dynode can result in the reemission of more than one electron from that surface.

Electrons leaving the photocathode have a kinetic energy of 1 eV or less.

Multiplication factor for a dynode is given by (number of secondary electrons emitted)/(primary incident electron), and should be a big as possible to maximize amplification.

Conventional dynode materials are BeO, MgO, and Cs3Sb.

NEGATIVE ELECTRON AFFINITY MATERIALS

The most successful of these materials have been GaP, heavily doped with a p-type of material like zinc, which then creates acceptor sites in the gallium phosphide.

(continues on about the way band gaps and conductor vs. valence bands work)

MULTIPLIER TUBE CHARACTERISTICS

1) 1) Focused linear structure

2) 2) Circular grid

3) 3) Venetian blind: one of the oldest, is now pretty much obsolete.

4) 4) Box-and-grid; old and slow, but standard for tubes of a large diameter

Continuous channel: hollow glass tube whose inner surface acts as a secondary electron emitter. A potential difference is created, which then attracts the electrons to one side of the tube.

Captain's Log, stardate 5/1/17

Met with Geng Yuan to work on creating graphs and working with the comparison scripts and root scripts for alpha source measurements.

ADVICE

If you plan on working with this research group for HONR269L, here's some advice for you so that you can get the most out of your experience and time:

1) Get your radiation safety training done ASAP. There's a guy named Bryan who does the training session, it's really fun and you gotta get it out of the way in order to do alpha source.

2) Go observe each of the three measurements ASAP, that way you can decide which one(s) really interest you. Once you decide that, go observe it another time or two so that you can get the OK to take measurements on your own.

3) TALK TO THE UNDERGRADS, GRADS, and POSTDOCS. Everyone is there because they love what they do--Professor Belloni and Geng-Yuan are more than happy to answer any questions you have, so don't be shy! (Easier said then done, but do it anyway!)

4) Read the Knoll textbook. It's intimidating because it's very long, so just pick one chapter to start with (probably the PMT chapter), meet with professor Belloni to talk about it, and then move on to a different chapter.

5) GET KEYS TO THE UNDERGRAD ROOM AND THE ROOM YOU TAKE MEASUREMENTS IN (You'll need Professor Belloni to send an email).

6) **If you're planning on doing alpha source, brush up on your Linux/python a bit so that you can run the script to compare measurements of different samples.

7) Have fun and make the best of it~