Tag: Geraldine Richmond

Missing Transverse Momentum Trigger Performance Studies for the ATLAS Calorimeter Trigger Upgrades

Presenter: Brianna Stamas

Faculty Mentor: Stephanie Majewski, Geraldine Richmond

Presentation Type: Oral

Primary Research Area: Science

Major: Physics

Funding Source: Presidential Undergraduate Research Scholars Program, UO Undergraduate Research Opportunity Program, $5,000

A basic question about our universe remains unanswered: what is everything fundamentally made of? Everything we know of only makes up 4% of the universe; a significant fraction of the remaining 96% is made of an unknown fundamental particle referred to as dark matter. In an attempt to identify the dark particle, the Large Hadron Collider (LHC) at CERN in Geneva, Switzerland is recreating the conditions of the Big Bang. The ATLAS Experiment is one of two general purpose detectors at the LHC. In anticipation of discovering new physics, the ATLAS detector will undergo numerous hardware upgrades in the coming years, one of which will be an improvement to the existing trigger system which is a 3-level hardware and software based system. This study focuses on the upgrades to the level-1 trigger. The LHC collides bunches of protons every 25 ns, which amounts to a lot of data in an extremely short period of time. Specifically, the missing transverse energy (ETmiss) trigger is crucial in being able to detect a previously undetectable particle. Therefore, we propose implementing a topological clustering inspired algorithm on the level-1 ETmiss trigger. The algorithm will be employed on the gFEX (global feature extractor) with 0.2×0.2 eta-phi granularity to be installed in 2019. This study analyzes the performance the algorithm for future implementation.

Modeling the Behavior of Pyruvic Acid at the Air-Water Interface

Presenter(s): Benjamin Muller − Chemistry

Faculty Mentor(s): Brittany Gordon, Dr. Geraldine Richmond

Poster 16

Research Area: Physical Chemistry

Studying the air-water interface provides valuable knowledge on important environmental systems like atmospheric aqueous secondary organic aerosol (aqSOA). Many small, aqueous organics that are known to contribute to aqSOA formation can further react in the air-water phase to form hydrated molecules. Since the atmosphere is a complex and variable place with many phases and interfacial regions it is difficult isolating this hydration process within particular organic systems. Modeling this behavior of hydrated organics at this interface is largely unknown. Pyruvic acid (PA) is an abundant atmospheric ketone found in aqSOA. Our research objective is to examine PA at the planar air-water interface using vibrational sum- frequency spectroscopy (VSFS). Sum frequency is a technique that shines visible and infrared light where air and water meet to understand molecular populations and behaviors of ordered molecules. Surface tensiometry measurements from the Wilhelmy plate will reveal the time dependency between PA and this complex system. Both techniques will help characterize how depth, conformational populations and orientation changes between the bulk, surface, and subsurface. This research will act as a platform to easily branch out to other systems of organics for future air-water interfacial studies.