1. The NSCL is funded in part by the National Science Foundation and Michigan State University. Results: the neutron source was located 19.9 inches from the end of the bar when our teachers put it in a “secret” location. 0.5 % error means we found the location of the neutron source in the 2 meter bar within 1 cm photo or drawing showing detector bar and position of neutron source? Sources of Error: cosmic ray background mismatched cables with different impedance varying neutron angle To improve our results : make many measurements for each position of the source. automating the averaging of many neutron hits About the NSCL Sally Hair Hanover High School, Hanover, NH The NSCL is located at Michigan State University in East Lansing, Michigan. In this laboratory, ions are created and accelerated by two different superconducting accelerators to half the speed of light. This fast beam of positive ions hits a target of metal so that collisions between the ions and target nuclei occur. The collisions causes the nuclei to fragment into smaller or sometimes large pieces that can be detected. Charged particles are steered to detectors by superconducting magnets, cooled to 4 Kelvin. Superconducting magnets can produce a larger magnetic field for a much smaller magnet. The goal of experiments at NSCL is to probe the limits of nuclear stability. Researchers study rare, or exotic isotopes to understand the forces that hold the nucleus together. About the NSCL Sally Hair Hanover High School, Hanover, NH The NSCL is located at Michigan State University in East Lansing, Michigan. In this laboratory, ions are created and accelerated by two different superconducting accelerators to half the speed of light. This fast beam of positive ions hits a target of metal so that collisions between the ions and target nuclei occur. The collisions causes the nuclei to fragment into smaller or sometimes large pieces that can be detected. Charged particles are steered to detectors by superconducting magnets, cooled to 4 Kelvin. Superconducting magnets can produce a larger magnetic field for a much smaller magnet. The goal of experiments at NSCL is to probe the limits of nuclear stability. Researchers study rare, or exotic isotopes to understand the forces that hold the nucleus together. Experiment 1: Identifying an Unknown Neutron Source using an Oscilloscope In this experiment, we used one bar of the MoNA detector and observed the light emitted when nuclei hit the scintillation material in the detector. We used an oscilloscope to measure the voltage signal produced in the photomultipier tube on the two ends of a bar of the MoNA detector. We compared the times and voltages from the photomultiplier tubes (PMT) at the two ends of the bar to learn where the nucleus hit the detector. If the nucleus hits the bar closer to one end than the other, the peak detected by the PMT closer to the hit is larger and happens at an earlier time. Experiment 2: Identifying an Unknown Neutron Source using SpecTcl This experiment was a follow-up to Experiment 1, however, in Experiment 2 we used SpecTcl software in order to get a more precise, reading from the PMTs with respect to charge and time. Whereas in the previous experiment, we were obliged to conduct several trials for a given position, the SpecTcl software is capable of mapping the time and energy of thousands of interactions in a short amount of time. As shown in Figure 2 below, the calibration data accumulated using SpecTcl yielded a more reliable regression line and allowed us to calculate with greater accuracy, the value of the unknown position. Experiment 3: Measuring Cosmic Rays & Muons In this experiment, we used the SpecTcl software to look at the various properties of cosmic ray collisions in the MoNA detector. The cosmic ray particles (called muons) we observed had much higher energy than the neutrons emitted by the neutron source. Cosmic ray muons deposit a small fraction of their energy in the MoNA detector and their signal is observed at about 20 MeV. Muons can travel through all the bars of the MoNA detector and our experiment will examine the muon signal in different bars to determine the different angles of the muons passing through the detector. About Nuclear Science Emily Finchum South Shore High School, Chicago, IL Most people are familiar with the classic model of the atom; there are protons & neutrons in the nucleus and electrons in the surrounding orbitals. Although this is the common model presented in the average high school chemistry class, this is nowhere near the full story. Scientists currently believe that composing the neutrons and protons are quarks and that, under the right conditions, we can break down the neutrons and protons to yield a wide array of differently-oriented quarks. Holding the quarks together are gluons - not as much of a physical entity in and of itself, but rather an attraction caused by the exchange of particles between two quarks. But now, we raise the next question: Where did all of the quarks come from? To answer this, we turn our heads to the cosmos, researching the effects of stars in populating the universe with different kinds of atoms. About Nuclear Science Emily Finchum South Shore High School, Chicago, IL Most people are familiar with the classic model of the atom; there are protons & neutrons in the nucleus and electrons in the surrounding orbitals. Although this is the common model presented in the average high school chemistry class, this is nowhere near the full story. Scientists currently believe that composing the neutrons and protons are quarks and that, under the right conditions, we can break down the neutrons and protons to yield a wide array of differently-oriented quarks. Holding the quarks together are gluons - not as much of a physical entity in and of itself, but rather an attraction caused by the exchange of particles between two quarks. But now, we raise the next question: Where did all of the quarks come from? To answer this, we turn our heads to the cosmos, researching the effects of stars in populating the universe with different kinds of atoms. Results: We found the unknown neutron source to be located at 0.769 m along the scintillator tube. 0.92% error shows that we were accurate to within 0.04 m of the actual position value. Sources of Error: Designation of the summation range on the SpecTcl software. Introduction to MoNA Laura Burhart Monhagen Middle School, Middletown, NY The MoNA is an expensive piece of equipment built to detect neutrons that result from the collision of large nuclei at the end of the Clyclotron process. These neutrons have no charge, so in order to be detected by MoNA, they need to push off an atom within one of MoNA’s scintillator bars to cause a wave of excited atoms within the bar. These excited atoms give off light, and those photons are then collected in a photomultiplier which amplifies the signal 30 million times. The energy signals are analyzed and the direction and speed of the neutrons is found. This data helps researchers get a better picture of the structures of rare nuclei. MoNA exists as a direct result of the teamwork between undergraduate students at nine different colleges and universities from across the country. By building MoNA, these students helped to further the science being done at the forefront of nuclear physics. Results: Points show the number of hits vs. angle of hits. Curve shows the expected cosine squared distribution of cosmic rays because muons at large angles decay during their longer trip through a thicker layer of the earth’s atmosphere. Experimental angular distribution is narrower than the cosine squared distribution. Sources of Error: Because of the finite extent of the MoNA detector, muons arriving at large angles may not be detected by both top and bottom bars of the detector. The distance calculations did not take into account the 10 cm thickness of the bars.