Virginia Tech QuarkNET Center - Report for Year 2016
The Virginia Tech QuarkNET Center currently has 2 active high school teachers, and is actively recruiting additional participants. Our lead teachers are Rebecca Jaronski and Nicholas Merrill.
This was an exciting summer for the Virginia Tech QuarkNET Center! We welcomed our new lead teacher and my new partner-in-crime, Nick Merrill. Nick is a teacher at the Roanoke Governor’s School and starting next summer we should be working together to really grow this center by adding new teachers from the area.
Lab work for the QuarkNET teachers in the High Energy Physic Lab really picked up where Rebecca left off last year. The lab is making great strides towards building the Micro-Chandler device for their great project of creating a detector for nuclear reactor safeguards. The Micro-Chandler requires a large number of operational and well-understood photomultiplier tubes (PMTs) and our small part of this large project is to help test and calibrate these PMTs. Last year Rebecca ran a cosmic ray/muon calibration with the cosmic ray detector Rebecca had assembled in the lab. Over the school year others tested the PMTs with a high-light setup. For this summer, the task of the QuarkNET teachers (Rebecca and Nicholas) was to test these PMTs with a low-light setup (see attached pictures for the electronics setup, pmt and laser and computer and notebook). They were looking for single PE (single photon emission), essentially the threshold light intensity that will cause the PMTs to function. In order to test this the teachers had a pulsed diode laser hooked up with some NIM hardware, and a computer system with an analysis program.(full description and pictures of the setup can be found on the PowerPoint presentation attached). The setup was already assembled and ready by the time the teachers started work this summer, so after being instructed by Dr. Sumanta Pal and Dr. Camillo Mariani in the basic design and purpose, the teachers started to work testing the PMTs. The teachers started off by finding an effective operating high voltage (HV) for each PMT by setting the LASER at a high intensity and looking for a peak around 3,000 ADC (this was essentially a measure of the light collected by the detector when a muon passed through it). The teachers found that in general, this ideal HV was between the cosmic ray test from last summer (these HVs were higher) and the high-light test (these HVs were lower). After determining the HV for that PMT, they started the LASER (see picture) at a low intensity and took data runs of 5 minutes, increasing the intensity each trial. Ideally, the data curve was supposed to show a peak that would tell them they saw the single PE, but they were not seeing that, even with taking longer runs and with adjusting the bin sizes and numbers on the histograms. It was determined to instead search for the ratio between the total number of counts and the count under the curve for that trial which had been previously determined to be around 30% for single PE. They were able to test all the free PMTs in the lab with this setup and the data resulted super-useful to the project.
Outside of the lab, the VT QuarkNET teachers had some other great chances for professional development. Merrill attended Fermilab Data camp, and Rebecca had the wonderful opportunity to spend a week in Greece at the Inspiring Science Education Summer School: “Discover the Cosmos: From Telescopes to Accelerators”. According to Rebecca: “It was an amazing experience, and it was not just the inclusive stay at the resort on Marathon Bay, or the fabulous tours of the Temple of Poseidon and the Acropolis! It was very interesting to talk to and work with teachers from outside of the US, as they have some different resources, methods, and philosophies and as teachers we are ALWAYS looking for something new, different, and exciting to engage our students in the classroom and get them truly interested in science. I have already signed up my high school astronomy class to participate in the Eratosthenes Experiment, which is an international collaboration managed by the ISE team, and have a great new tool for creating web quests and interactive lessons for students and am very excited to use these in the year to come!”