Discipline: Physics
Subcategory: Physics (not Nanoscience)
Session: 3
Room: Exhibit Hall A
Austin DeMurley - Suffolk County Community College
Co-Author(s): Raul Armendariz, Queensborough Community College, Bayside, NY; Corey Stalerman, Queensborough Community College, Bayside, NY; Jonathan McCarthy, Suffolk County Community College, Selden, NY
Cosmic Rays are ionized atomic nuclei; 90% are Hydrogen (Protons), 9% Helium (Alpha Particles), 1% heavier atomic nuclei (HZE ions). These particles are jettisoned from the sun, active galactic nuclei, supernovae, and quasars at relativistic speeds. When these primary Cosmic Rays collide with Earth, they first strike nucleons in the upper atmosphere. These high energy collisions cause secondary Cosmic Ray showers of daughter particles including charged Pions, which undergo leptonic decay into Muon and Muon-Neutrino pairs. These Muons experience relativistic time dilation, allowing the Muons to reach Earth-bound detectors despite a mean lifespan of 2.2 microseconds. The CUNY Cosmic Ray Muon Detector array uses sheets of polyvinyltoluene (PVT) plastic with fluorescent hydrocarbon molecules as detection media. Charged Muons collide with these counters, ionizing molecules which emit photons that can be detected using photomultiplier tubes. In creating an array of detectors in multiple sites across New York to study particle astrophysics and atmospheric physics, a streamlined experiment including power distribution, network, and control circuits, experiment and equipment enclosures must be developed. Experiment control includes transferring power and data between various subsystems, including GPS, sensors for atmospheric conditions, Ardiuno and Raspberry Pi. LM317 IC were thoroughly tested for use as Power Distribution Units to ensure a reliable and accurate power supply for EMCO high voltage converters necessary to power the photomultiplier tubes. Characterization, modifications and circuit design are presented. Enclosure designs are streamlined to reduce size and cost. Scintillator and photomultiplier tube enclosures were found to be leaking light, introducing ambient noise. Detecting the photons emitted by scintillator detectors via photomultiplier tubes requires a noise free environment as photomultiplier tubes are highly sensitive and produce their own noise due to the high voltages involved (dark rates). Further characterization of experimental equipment is presented. Future work includes the development of 10 fully developed prototypes for rigorous testing under full experiment conditions. Design modifications resulting from this initial prototype testing, continuing development of DAQ Front End, and other equipment improvements by colleagues is expected. References: Hill, W., Horowitz, P., 2015. The Art of Electronics. Third Edition. ISBN 978-0-521-80926-9. Armendariz, R., Zhang, A., Buitrago, D. J., Cheung, T., Stoddard, G., Jaffe, D. E., 2017. Design and construction of a cosmic ray detector array for undergraduate research at the City University of New York. Fall 2017 Mid-Atlantic ASEE Conference. Paper ID #21006.
Funder Acknowledgement(s): This research was funded by an NSF grant to CUNY Queensborough Community College's Physics REU program under Dr. David Lieberman. Scholarship funding was provided by an NSF grant to SUNY Suffolk County Community College?s NSF-STEM program under Dr. Candice Foley.
Faculty Advisor: Raul Armendariz, rarmendariz@qcc.cuny.edu
Role: For this research, I designed the enclosures and circuit assembly for power, distribution, and controls circuits, including choosing all necessary components and making changes necessary based on updates to experiment and DAQ design by colleagues. I tested LM317s for use as power distribution units, including full experiment set up with EMCO converters and photomultiplier tubes. I discovered pre-existing scintillator and photomultiplier tube enclosures were leaking light, introducing noise to test experiments, and tested and developed solutions.