Colloquium Archive

Thursday, September 12th
Welcome Back and Introduction to the department

Come and learn about the departmental expectations for our Physics majors. Get to know everyone in the department. Ask questions! Eat pizza!

Noon
Tome 115
Pizza provided

Thursday, October 31st
Student Research Talks

Amanda Baylor '20
"Accelerating Astrophysical Discovery with Reduced Order Modeling”

Gravitational wave detectors are now more sophisticated than ever before, bringing with them a new and exciting era of gravitational wave physics. There is now a greater need for fast and accurate inference methods to extract astrophysical information about their sources. Current methods of parameter estimation take excessive computational time. We have built a reduced order model that generates significant speedup on Bayesian inference analyses and produces probability distributions on the parameters of these sources, with an application to a real binary neutron star detection.

and

Ali Siddiqui '22
"Study and Characterization of Graphene Induced Hybrid Structures"

Graphene is an allotrope of Carbon in the form of two-dimensional hexagonal lattice. Its special properties (flexibility, strength and conductivity), and the demand for miniaturization of electronic devices has lent heavily to the research and development of graphene induced hybrid structures. Graphene induced Metal Semiconductor Metal (MSM) are one of such hybrid structures. The electrical and optical response of Graphene induced MSM was analyzed to study the sample’s potential compatibility, and its potential use in optical sensing devices and as photodetectors.

Noon
Tome 115
Pizza provided

Thursday, November 14th
Jennifer Eigenbrode, Goddard Space Flight Center
"Organic matter in 3.5-billion-year-old mudstones from an ancient lake in Gale Craters, Mars"

The Sample Analysis at Mars (SAM) instrument suite onboard the Mars Science Laboratory’s Curiosity rover has detected the presence of geologically-refractory organic matter in the 3.5-billion-year-old lacustrine mudstones studied at the base of the Murray formation at Pahrump Hills, Gale crater, Mars. Evolved gas analysis (EGA) experiments show the release of a diverse set of organic molecular components in the 500-860°C temperature range. Theses organics consist of aliphatic, aromatic, and sulfur-bearing (i.e., thiophenes, dimethylsulfide and thiols) organic volatiles. The latter were also identified by gas chromatography- mass spectrometry (GCMS). The molecular distributions observed are specific to samples and cannot be explained by SAM’s instrument background. The EGA observations are consistent with the pyrolytic cleavage of organic fragments from macromolecules indigenous to the mudstones, though some portion could also be derived from the thermal release of organics entrained within other sample components. Both the sulfidic and macromolecular nature of the organic matter suggest that these may be key mechanisms for the organic preservation over geological timescales, as they are on Earth.

The source of the martian organic matter remains unknown. SAM-like EGA of the Tissint meteorite, which contains abiotic organic matter formed from geological processes, the Murchison carbonaceous chondrite, and a terrestrial Jurassic paleosol containing geologically reworked biological materials all showed the release of similar organic components above 500°C.

The mission objective, to search for organic carbon in situ, has long been motivated by the broader goal to search for possible life on Mars, in which carbon molecules are the building blocks. SAM’s findings provide the stepping stone needed to guide future missions that aim to search for signatures of ancient life.

Jen Eigenbrode’s bio online: https://science.gsfc.nasa.gov/sed/bio/jennifer.l.eigenbrode

Noon
Stafford Auditorium
Pizza provided

Tuesday, November 19th
Sigma Pi Sigma Keynote Speaker, Induction Ceremony and Dinner
LTC Jeff Kendellen '00 - Keynote Speaker
"Physics as a Foundation for the Military"

Lieutenant Colonel Jeff Kendellen will discuss his experiences during 20 years in the military and how a degree in physics served as an outstanding foundation for solving complex problems and providing solutions to senior leaders.  LTC Kendellen will discuss small modular nuclear reactors, nuclear weapon effects, and ballistic missiles.

Sigma Pi Sigma Inductees: Amanda Baylor, Ming Hua, Rachel Krewson, Aidan Pidgeon and Olivia Young

4:30pm
Tome 115
Dinner to follow at 6pm in Holland Union Building Social Hall *must sign up in Tome 201 by November 12th