Stellar evolution and the synthesis of the elements are governed by key nuclear reactions, among which the fusion of 12C with an alpha particle to form 16O, denoted as the 12C(α,γ)16O reaction, is "of paramount importance". The ratio of carbon to oxygen produced during stellar helium burning, which is determined by the 12C(α,γ)16O reaction, allow us for example to predict the fate of massive stars, whether they end up as neutron stars or black holes. Despite five decades of study, this reaction's cross section remains poorly constrained at the astrophysically relevant energies. This thesis presents the development and implementation of a new method to measure the cross-section of the 12C(α,γ)16O reaction by measuring the time-reverse process – the 16O(γ,α)12C reaction – using a Time Projection Chamber (TPC) operated in intense γ-ray beams. The first-generation optical readout TPC (O–TPC) was constructed at UConn and used at the High Intensity γ source (HIγS) facility at Duke University. Building on these results, a next-generation electronic readout TPC (eTPC) was constructed and commissioned at the University of Warsaw, incorporating a fully digital electronic readout system for high-rate data acquisition. The eTPC was exposed to quasi-monoenergetic γ-rays from 8.51–13.9 MeV, corresponding to Ecm=1.4-4.8 MeV of the 12C(α,γ)16O reaction. A comprehensive analysis framework was developed to identify the 16O(γ,α)12C events and reconstruct their kinematics. This permitted angular distributions of the photo-dissociation events to be examined. The analyzed angular distributions yield results which are consistent with a fundamental prediction of quantum mechanics, a feat not seen in earlier data sets. The results demonstrate that this method can achieve accurate event reconstruction, clean event separation, accurate energy calibration, and angular resolution sufficient for astrophysical studies. This work establishes the validity of our new method for precision measurement of the 12C(α,γ)16O reaction through its time reverse process. This paves the way toward future measurements at lower energies with reduced uncertainty and improved extrapolation to stellar conditions.

This dissertation focused on the design and development for fluorescent sensor array for the foodborne pathogenic bacterial and biofilm identification with machine learning techniques. it also includes the investigation of interfacial biofilm monitoring and quantification for better pathogenic biofilm control and food safety.

Write your memoirs to share in class. These can be short unrelated pieces or part of a larger work. New members are welcome.Facilitator: Cathy Belanger

This is a full day of Caring Community Pop-Up: Post Election Connection events - 12p-1p: Know Your Rights workshop with Junta hosted by the Rainbow Center Out to Lunch Lecture Series (Rainbow Center, Storrs, Student Union rm 403)1p-3p: Drop-In any time to continue to Pick Up the Thread - The Well-Being Collective and the Humanities Institute, with the support of the UConn Library, Native American Cultural Programs, Student Activities, and Student Health and Wellness, present a moment of pause, inclusivity, and reflection one year after the 2024 election for all members of the UConn community. Come to relax, reflect, and share in collective art-making and meaningful dialogue. There will be faculty and staff experts available for pointed conversations, and materials for a collective fiber arts project—representing the thread that weaves us all together. We invite everyone to explore ways to create and maintain community in politically charged times. (Native American Cultural Programs Space, Storrs, Student Union rm 103)

Join us for this interactive session to discuss how best to support doctoral students while they explore career options. This session will highlight specific tools students can use whether they are exploring faculty roles, non-faculty roles, or both. Participants will learn how to guide PhDs through the development of a career plan and through career-related conversations. The discussion will be applicable across disciplines and will equip faculty with strategies used nationwide to help graduate students thrive.See more about all Timely Topics offered by The Graduate School. (https://grad.uconn.edu/timely-topics/) Please register (https://uconn.kualibuild.com/app/636957bead4b66cb6fe9611e/run) to receive a Webex link for this event.