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Click here for:Date: | Thursday |
Time: | 1:30-3:00 PM |
Place: | Willard Hall, Room 004, OSU |
& Nielsen Hall, Room 365, OU | |
& Online Access | |
Inquiries: | joseph.haley@okstate.edu or kao@nhn.ou.edu |
Date: | Thursday |
Time: | 3:30-4:30 PM |
Place: | PS 110 |
Inquiries: | perk@okstate.edu |
Date: | Friday (bi)weekly |
Time: | 2:30 PM |
Place: | PS 147 |
Inquiries: | perk@okstate.edu or mario.borunda@okstate.edu |
No talks scheduled
No talks scheduled
First Week of Classes
Martin Luther King Day: Monday, January 16
Speaker: | Dr. John Stupak III |
Homer L. Dodge Department of Physics and Astronomy | |
University of Oklahoma | |
Date: | Thursday, January 19, 2017 |
Time: | 1:30 PM |
Place: | Willard Hall, Room 004, OSU |
& Nielsen Hall, Room 365, OU | |
& Online Access | |
Title: | Search for Anomalous HVV Couplings in Associated Higgs Production with H→bb |
Speaker: | Dr. John Stupak III |
Homer L. Dodge Department of Physics and Astronomy | |
University of Oklahoma | |
Date: | Thursday, January 19, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | The Matter/Anti-Matter Asymmetry and the Higgs Boson |
The early universe is believed to have contained equal parts matter and anti-matter, yet today the universe is dominated by matter. The origin of this matter/anti-matter asymmetry is unknown, requiring new physics to provide an explanation. Could the recently discovered Higgs boson provide a clue?
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
Second Week of Classes
Speaker: | Dr. Pedro A.N. Machado |
Theoretical Physics Department | |
Fermilab | |
Date: | Thursday, January 26, 2017 |
Time: | 1:30 PM |
Place: | Willard Hall, Room 004, OSU |
& Nielsen Hall, Room 365, OU | |
& Online Access | |
Title: | Beyond Standard Neutrinos |
Speaker: | Dr. Gabriel O. Sawakuchi |
Department of Radiation Physics, Division of Radiation Oncology | |
The University of Texas MD Anderson Cancer Center | |
Date: | Thursday, January 26, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Time-lapse Monitoring of DNA Damage Response Induced by Clinical Particle Beams |
Particle therapy (PT) using proton or carbon (C-) ion beams is emerging as a promising modality for cancer treatment and becoming increasingly available worldwide. More than 61 HT centers are currently treating cancer patients. The MD Anderson Cancer Center has treated more than 6,000 patients with proton therapy since 2006. Worldwide, approximately 51 PT centers (17 in the United States) are either under construction or being planned. From a physical standpoint, PT beam dose deposition is highly favorable, following a Bragg curve as a function of its depth in tissue. The lower entrance doses and elimination of exit doses can produce superior conformal dose distributions to the target volume compared with standard radiotherapy using megavoltage (MV) x-ray beams. Thus, the rationale for using PT beams lies in reducing the integral dose and sparing surrounding healthy tissues and critical organs, minimizing treatment related complications and reducing the risk of radiation-induced secondary cancers. Protons and C-ions are charged particles that continuously interact with tissue, slowing as they penetrate it, and leaving a track of ionizations in their paths, which are quantified in terms of the linear energy transfer (LET). The LET increases as the energy (or speed) of the particle decreases. Consequently, the LET increases as a function of depth in tissue. At their entrance to the body, the LET is low and at the tumor volume and end of the particle beam range, the LET increases by more than an order of magnitude. The biological damage produced by the therapeutic PT beams depends on LET in addition to absorbed dose. However, remarkably little is known of the differential biologic response PT beams produce, which reduces their clinical application. Moreover, a lack of experimental techniques capable of measuring particle tracks in live cells is an additional drawback for radiation biology experiments investigating mechanisms of cell death, pathways of cell repair, and mutation induction. In this talk I will present a new technique developed by our group that uses beamline microscopy of live cells in combination with fluorescence nuclear track detectors to precisely investigate DNA damage response induced by clinical PT beams.
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
No colloquium scheduled
Speaker: | Dr. Christopher J. Fennell |
Department of Chemistry | |
Oklahoma State University | |
Date: | Thursday, February 9, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Virtually Molecules: From simple 2D models to immersive 3D experiences in molecular worlds |
Molecular modeling can act as a bridge between laboratory experiments and theories for our understanding of the behavior of matter. In this partly interactive presentation, I present several different forms of molecular modeling that we use in our research lab to explain and explore how molecules interact and how those interactions give rise to material properties. Starting with the construction of simple two-dimensional models, we can show why water has many of its anomalous thermodynamic properties. Moving into the 3rd dimension, we use 3D printing to bring models out of the flat world of computer screens to give others a tactile experience with molecular structure and interactions. When such physical models are limiting, we use virtual molecular environments we assemble for interactive Oculus Rift systems to, instead of bringing molecules out of the screen, insert people into molecular worlds.
Note: Refreshments will be served in Physical Sciences Room 105 at 3:00 PM. All students are welcome!
No colloquium scheduled.
OSU Research Week
Speaker: | Dr. Saki Khan |
Department of Physics | |
Oklahoma State University |
Postponed till May 4.
Speaker: | Dr. Ian R. Sellers |
Homer L. Dodge Department of Physics and Astronomy | |
University of Oklahoma | |
Date: | Thursday, March 9, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Routes to High Efficiency Solar Cells Using Low-Dimensional Systems |
Recently there has been significant interest in renewable energy as an alternative source of power to replace traditional fossil fuels and reduce our dependency on oil. Photovoltaics—the conversion of the sun’s energy to electricity—is an attractive approach since it offers a free and abundant source of clean energy. However, current commercial solar cells are limited to conversion efficiencies or the order of 30% due to the poor spectral matching of single bandgap semiconductors to the sun’s irradiance. To enable the large-scale implementation of solar cells for utility-scale energy applications improvements in power conversion efficiency and lower system costs must be achieved. To circumvent the fundamental limitations of single energy-gap solar cells, devices based on third generation (3G) processes have been proposed. In this presentation I will introduce such concepts, which implement low-dimensional systems into next generation solar cells, to try to harness more fully the solar resource and increasing the power conversion efficiency for these systems.
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
Spring Break
APS March Meeting
Speaker: | Mr. Timothy G. Perk |
Department of Medical Physics | |
School of Medicine and Public Health | |
University of Wisconsin | |
Date: | Thursday, March 23, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | PET Imaging Physics and Some Clinical Applications |
In oncology, positron emission tomography (PET) imaging is used for staging and response assessment of cancer patients. Most of the current use of PET imaging is restricted to qualitative imaging, i.e., is there a tumor or not? But medical physicists are working to make PET imaging quantitative, which will allow us to assess how much said tumor is changing over the course of a treatment. In this talk I will briefly describe the physics of PET imaging, how PET is used in the care of cancer patients, and how quantitative PET can be used. Finally I will describe some of my work being done to assist physicians in reading these images.
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
Speaker: | Dr. Scott C. Noble |
Department of Physics and Engineering Physics | |
University of Tulsa | |
Date: | Thursday, March 30, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Lighting Up Inspiraling Binary Black Hole Systems |
Accretion disks around supermassive binary black holes offer a rare opportunity to probe the strong-field limit of dynamical gravity using turbulent plasma as a lighthouse. Accurate simulations of these systems using a variety of configurations will be critical to interpreting future observations of them. In this talk, we will present our latest results of 3-d general relativistic magnetohydrodynamic supercomputer simulations of accreting binary black holes during the post-Newtonian inspiral phase of their evolution. The goal of our work is to explore whether these systems provide a unique means to identify and characterize them with electromagnetic observations. We will present results that show how our predicted light curves vary with respect to mass ratio, binary separation, amount of accreting magnetic flux, and the order of accuracy in the post-Newtonian approximation. We will also provide a context for our results and describe our future avenues of exploration.
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
Speaker: | Dr. Dongping Zhong |
Robert Smith Professor, Department of Physics | |
& Department of Chemistry and Biochemistry | |
The Ohio State University | |
Date: | Thursday, April 6, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | A New Electron-Transfer Strategy Operating for DNA Repair by All Photolyases |
Photolyase is a photoenzyme using blue light to repair UV-induced DNA lesions in three life kingdoms. Although earlier studies on microbial photolyases revealed a critical electron-tunneling pathway for the repair mechanism, it is unknown if such electron superexchange can also operate in distant eukaryotic photolyases. Here, using femtosecond spectroscopy we show our systematic dissection of the repair process with seven electron-transfer reactions among ten elementary steps on various photolyases in all life branches. We found a new, unified electron-transfer strategy for all photolyases with bifurcated routes through a conserved structural configuration. Both pathways are operative in repair depending on the relative reduction potentials and converged at damaged-DNA site for efficient repair. From lower microbes to higher eukaryotes, the electron exploits from mainly direct tunneling along one route to dominant two-step hopping on the other path with the same conserved active-site structure through evolution.
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
Speaker: | Dr. Mario C. Díaz |
Center for Gravitational Wave Astronomy and | |
Department of Physics | |
The University of Texas Rio Grande Valley | |
Date: | Thursday, April 13, 2017 |
Time: | 1:30 PM |
Place: | Willard Hall, Room 004, OSU |
& Nielsen Hall, Room 365, OU | |
& Online Access | |
Title: | Observing the First Kilonova |
A long standing mystery in astrophysics is the source of short very energetic Gamma Ray Bursts (GRBs). Scientists have suspected for a while that the merger of two compact objects such as neutron stars or black holes could be the birthplace of such phenomenon. Observing a merger through gravitational wave detectors, gamma ray observatories (such as Fermi) and optical observatories will provide a very complete picture into the nature of an extremely elusive phenomenon which has been dubbed a kilonova. An understanding of its astrophysics could also illuminate the nature of the production and abundance of the more heavy elements that we find in the universe. I will discuss some of the main expected features of kilonovae events and the plans to detect and study them through multi-messenger astronomy.
Speaker: | Dr. Mario C. Díaz |
Center for Gravitational Wave Astronomy and | |
Department of Physics | |
The University of Texas Rio Grande Valley | |
Date: | Thursday, April 13, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | The Quest of a Century: The mysteries, failures, uncertainties and final success in proving Einstein right after 100 years |
On February 11, 2016 the National Science Foundation announced to the world the discovery of gravitational waves. This discovery was the result of many years of speculation and trials and errors from many scientists. And the first detection itself, the result of the vision of a group of pioneers and about thousand scientists and engineers that participated in implementing it, is the technological feat that made it possible. In this talk I will describe some of the relevant aspects of this history and the characteristics of the discovery itself. This first detection has also opened a new window to the universe: gravitational wave astronomy. I will finish my talk addressing the importance of this new window for astrophysics and for improving our understanding of nature.
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
Speaker: | Dr. William H. Beasley |
Professor Emeritus, School of Meteorology | |
University of Oklahoma | |
Date: | Thursday, April 20, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Everything You Always Wanted to Know about Lightning, But Were Afraid to Ask |
While over the last several decades we have made considerable progress towards understanding the physics lightning, we still do not have a firm grasp of how the lightning discharge is initiated. The electric fields in thunderclouds are not strong enough to produce spontaneous electrical discharges. In this talk, I present a brief survey of what we know about the physics and phenomena of lightning, included advances in light detection such as the Oklahoma Lightning Mapping Array. I’ll also address what we still do not know about lightning, including the possible role of cosmic ray extensive air showers in lightning initiation.
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
Speaker: | Dr. Tathagata Ghosh |
Department of Physics | |
Oklahoma State University | |
Date: | Thursday, April 27, 2017 |
Time: | 1:30 PM |
Place: | Willard Hall, Room 004, OSU |
& Nielsen Hall, Room 365, OU | |
& Online Access | |
Title: | Probing Squeezed Bino-Slepton Spectra with the Large Hadron Collider |
In this talk, I’ll discuss a Minimal Supersymmetric Standard Model scenario in which the only light superparticles are a bino-like dark matter candidate and a nearly-degenerate slepton. It is notoriously difficult to probe this scenario at the Large Hadron Collider, because the slepton pair-production process yields a final state with soft leptons and small missing transverse momentum. We examine this scenario where the mass difference between the lightest neutralino and the lightest slepton (Δm) is less than 60 GeV, focusing on the process in which additional jets provide a transverse boost to the slepton pair. I’ll present search strategies that can dramatically improve both signal sensitivity and the signal-to-background ratio, permitting discovery at the Large Hadron Collider with a reasonable integrated luminosity over the interesting region of parameter space. Although we focus on a particular model, the results generalize to a variety of scenarios in which the dark matter and a scalar lepton partner are nearly degenerate in mass.
Speaker: | Mr. Hem B. Moktan |
Department of Physics | |
Oklahoma State University | |
Date: | Thursday, April 27, 2017 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Structure and Dynamics Studies of Homologous Pairing Protein 2 (HOP2) |
Proteins serve many crucial functions in essentially all biological processes. The three-dimensional structure of a protein defines not only its size and shape, but also its function. Therefore knowledge of its functional architecture is essential. In this talk, I present my research work where experimental NMR techniques were used to investigate 3D structure of HOP2. HOP2 is a protein that has been found to be critical in meiotic cell division when high levels of genetic exchanges take place. Also, molecular dynamics simulation works to investigate the DNA binding dynamics of HOP2 will be discussed.
Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3:00 PM. All students are welcome! Refreshments will be served.
Prefinals Week
The colloquium by Dr. Saki Khan has been cancelled, as he will be out of town for a job interview.
Finals Week
No talks scheduled.
No talks scheduled.
No talks scheduled.
Speaker: | Dr. Borut Bajc |
Department of Theoretical Physics | |
Jožef Stefan Institute | |
Technological University, Ljubljana, Slovenia | |
Date: | Tuesday, June 6, 2017 |
Time: | 1:30 PM |
Place: | PS 147 |
Title: | The UV Limit in GUTs |
No talks scheduled.
No talks scheduled.
Speaker: | Shaikh Saad |
Department of Physics | |
Oklahoma State University | |
Date: | Thursday, June 29, 2017 |
Time: | 2:00 PM |
Place: | PS 147 |
Title: | Fermion Masses and Mixings, Leptogenesis and Baryon Number Violation in Unified Theories |
Last Updated:
This page was prepared by Jacques H.H. Perk.
jhhp@jperk.phy.okstate.edu