Bulletin of the American Physical Society
Mid-Atlantic Section 2022 Meeting
Volume 67, Number 20
Friday–Sunday, December 2–4, 2022; University Park, PA, Pennsylvania State University
Session F01: Poster Session |
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Room: Pennsylvania State University Huck Life Sciences Bld 301, 3rd Flr Bridge |
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F01.00001: Energy Transfer in Sm3+:YAlO3 John K Krebs, Alex Sobey-Strick The luminescent properties of lanthanide doped materals find use as phosphors for lighting, scintillators, and lasers media. Yttrium aluminum perovskite (YAP) has excellent thermal, mechanical, and optical properties and is a less studied phase in the Al2O3-Y2O3 system compared to the more well-known Y3Al5O12 (YAG). Because of the resonance overlap between different electronic transitions in the Sm3+ impurity ions, radiationaless energy transfer occurs between impurities at higher impurity concentrations. We report energy transfer studies on combusion synthesized samples. The sample crystal structure was characterized by x-ray diffraction and the impurity ion site identified through laser induced fluorescence spectroscopoy. Lifetime measurements were carried out and fitted using the Inokuti-Hirayama model. Parameters from the fits were used to compare the energy transfer in our small-scale phosphors to single crystals. The results demonstrate that liquid-phase mixing of host and impurity ions produces materials with well distributed impurity ions and that energy transfer between ions decreases in fine grain powders compared to bulk materials. |
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F01.00002: Quantum Dynamics in a Double-Well Potential Using Quasiclassical Methods Nicole H Drew, Simon Gelin, Ismaila Dabo, Venkatraman Gopalan, Martin Bojowald The quartic double-well potential is used to model a variety of physical systems, such as coupled quantum dots, due to its simple form that permits straightforward realization and analysis. In this work, we investigate the dynamics of non-equilibrium quantum states in one-dimensional double wells using nonstandard "quasiclassical" techniques that treat a wave packet's average position and standard deviation on equal footing in an effective potential landscape while incorporating Heisenberg's uncertainty principle. On this poster, we will outline the theory of the quasiclassical method, apply this method to find oscillation frequencies of states hosted in the double well, compare these results to those computed using the standard Schrödinger equation, and discuss the relative advantages or drawbacks of these two techniques. |
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F01.00003: Memory of a Cyclic Multiphase Flow in a Porous Medium Jennifer M Lee, Jennifer M Lee, Ashbell Abraham, Nathan C Keim One potential method for reactive mitigation of climate change is carbon sequestration, which involves the cyclic injection of CO2 into saline aquifers for removal from the atmosphere. Studies of memory formed by cyclic multiphase flow can possibly inform and improve the efficiency of this type of carbon sequestration. In this work, we focus on memory in the triple phase boundary of a wetted porous medium, also referred to as the contact line. We cyclically inject and withdraw a constant training volume of deionized water from a porous medium made of glass beads. The cyclic driving procedure eventually relaxes the contact line to a steady state shape. Afterwards, we drive the contact line with volume amplitudes that are less than the training volume, and we observe that the smaller amplitudes alter the contact line away from its steady state shape while the training amplitude restores it. This behavior resembles the phenomenon of return point memory, better known in ferromagnets. We propose further experiments to characterize this memory, including its capacity to retain traces of multiple driving amplitudes. |
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F01.00004: Water harvesting through capillary network in a porous domain Xuewei Zhang, Sylvie Lorente Porous media enabling a fluid to flow through them find multiple applications in engineering, geothermal sciences, biosensors, and oil recovery. Transport phenomenon in porous media depends on the porosity, the pore size distribution and the connectivity. In this study, we propose a methodology to design capillary networks in 2-D and 3-D by connecting multiple fluid sources to one single outlet. The network is morphed every time a new source is connected to ensure maximum flow access through the porous medium. The generated networks are compared to networks with minimum volume and surface area. The impact on the number of fluid sources and the radius ratio between channels are discussed. The Hess-Murray’s law suggests that the optimal value for the radius ratio , while we discover that a higher and wide range of is able to enhance the flow performance of the capillary network. The proposed model can help to understand how to improve the fluid transport through the porous domain by predicting the fluid network configuration, for a given porosity, allowing to harvest the maximum flow rate. |
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F01.00005: An inquiry on the role of cosmic muons-banded iron formations interactions-induced spin-controlled enantioselective synthesis in the emergence of biomolecular homochirality and implications for the biosphere during weakening in the geomagnetic field Moses T Bility The dominant hypothesis for the origin of life posits that serpentinization is the driving mechanism for the emergence of biomolecules and life in the Precambrian era. The serpentinization of peridotite generates magnetite (iron oxide) and silicate minerals, suggesting that magnetized magnetite-associated spin-controlled reactions could have played a significant role in the emergence of life. The biomolecules of life are homochiral and biomolecular homochirality is coupled with electron spin selectivity. Recent studies proposed that cosmic spin-polarized muons or magnetized iron oxide-induced spin-polarized electrons interactions with mirror symmetrical pairs of chiral biomolecules resulted in the emergence of biomolecular homochirality. In agreement with S. Furkan Ozturk and Dimitar D. Sasselov, PNAS 2022, I propose that the emergence of biomolecular homochirality in the Precambrian era was mediated by spin-control enantioselective synthesis induced by spin-polarized electrons that were ejected from iron oxide-silicate banded iron formations by iron nuclei-derived spin-polarized muons. I also proposed that the coupling between biomolecular homochirality and spin-selectivity suggests that spin-control reactions could also modulate the biosphere after the Precambrian era. Here, I propose and provide evidence suggesting that interactions between aberrant iron nuclei-derived spin-polarized muons and new iron oxide-silicate rocks derived from serpentinization in a severely weakened geomagnetic field could result in the generation of an aberrant lithospheric magnetic field that mediates the spin-control synthesis of aberrant homochiral biomolecules and disease in hominids and other animals. |
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F01.00006: Study of Photocatalytic Degradation for Water Filtration Using Computational Analysis Jaeyoon Richard Kim In this paper, open-source molecular editing programs such as Avogadro and Gaussian with an auto-optimization feature that can calculate the theoretical values of a molecule’s physicochemical properties are used to model the nano-scaled compounds for water filtration. |
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F01.00007: An Assessment of the Role of Redox Metals Causing Oxidative Stress in Parkinson's Disease Hyunmin Kaelyn Lee, Richard Kyung Redox metal ions are involved in the pathogenesis of Parkinson's disease(PD), and researchers have been studying and developing novel therapeutic chelating agents for the treatment. Chelation therapy is an effective form of treatment for neurodegenerative diseases, and the proper molecule is needed to perform this task of reducing metal ion levels that can be harmful by producing reactive oxygen species(ROS) and damaging cells in the brain. Through computational analysis of various confirmed metal ion chelators, certain compounds such as metal-organic frameworks(MOFs) molecules and chelators were modeled and analyzed to figure out their efficiencies as chelators for the therapy of PD. Among the tested molecules, for example, UiO-66-BDC showed thermodynamically stable and extremely high reactivity. Additionally, its high surface area to volume ratio allows it to have a significantly higher uptake of redox-active metals relative to other chelators. |
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F01.00008: Birdsong Syllable Recognition Using Neuromorphic Computing Kevin Sargent, Leonardo E Tavares, Dezhe Z Jin Neuromorphic computing enables highly parallel and energy-efficient computation compared to traditional CPUs. These features make it an ideal candidate for the implementation of continuous speech recognition, which requires low-latency. Audio data can be converted into sparse, spatiotemporal sequences of spikes which are input into a spiking neural network that performs speech recognition. The parallel nature of neuromorphic hardware enables a template matching network to be implemented using a large number of templates while minimizing the latency of recognition. Birdsong audio is an ideal dataset for developing speech recognition networks, as it possesses distinct syllables that can be recognized in a similar manner to human speech. Using Intel's Loihi neuromorphic chip, we are implementing a template-matching spiking neural network to perform recognition of syllables in birdsong recordings. |
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F01.00009: A computational model investigating the plausibility of generating precisely timed and reliable bursts in songbird nucleus HVC using the inputs from the thalamic nucleus UVA Derek Sederman, Yevhen Tupikov, Nader Nikbakht, Michale Fee, Dezhe Z Jin Zebra finch song is driven by precisely timed and highly reliable bursts of projection neurons in the sensory-motor nucleus HVC (proper name) that form ultra-sparse burst sequences. The neural mechanism for the bursts is currently debated. One view is that bursts are generated in HVC through a synaptic chain mechanism (Long et al., 2010 and Egger et al., 2020). An alternative is that the thalamic nucleus Uvaeformis (UVA) drives HVC bursts as part of a distributed network through the brainstem, UVA, HVC, and RA (Hamaguchi et al., 2016). Here we computationally assess the plausibility of the distributed model. Single neuron recordings in UVA during singing show that UVA neurons that project to HVC contain timing information during the song, but compared to HVC projection neurons, fire densely in time and are much less reliable. To examine if convergence of UVA projection neurons to HVC can produce the precision and reliability of the HVC bursts, we use a resampling technique to scale up the number of UVA neurons. This allows the number of sampled UVA neurons to match the number of UVA projection neurons while preserving the timing and reliability of recorded UVA neurons. Using the sampled UVA neurons, we create a procedure to train model HVC projection neurons. Each model HVC neuron is trained to burst at a putative time in response to direct excitatory UVA input and indirect inhibitory input through HVC interneurons. Training is performed with learning rules similar to those previously used to characterize learning capacities of neuronal circuits (Memmesheimer et al., 2014). HVC projection neurons are simulated with an integrate-and-fire model and a more biologically informed two-compartment model that includes a dendritic calcium spike. In both models, trained HVC projection neurons produce precise, sparse bursts only when the convergence from UVA to HVC is high enough to overcome the inconsistency of UVA firing patterns. However, this level of convergence is not supported by experiments that have traced the axons from UVA to HVC. When realistic convergence is used, trained HVC projection neurons are unable to reproduce the precision and reliability experimentally observed in HVC. Noise in HVC interneurons further exacerbates this issue. Our work casts doubt on the mechanism of UVA driving HVC bursts. |
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F01.00010: Classification of budgerigar vocalizations Autumn R Zender, Leonardo E Tavares, Lyn Ackert-Smith, Zetian Yang, Michael A Long, Dezhe Z Jin Parrots are capable of an astounding degree of vocal learning and rich social interactions, making them an important model system for understanding the neural basis of communication. Here we devise a method for automatic classification of the vocalizations of the budgerigar, a small Australian parrot. Pairs of adult male birds were recorded, producing vocal elements including warble, contact call and alarm call. The most complex of these vocalization types is warble, which contains continuous vocal gestures with varying durations. Acoustic features in warbles can resemble vocalizations in other categories as well as cage noises due to birds' movement. These properties pose challenges to many schemes designed for birdsong syllable classification. Inspired by the fact that neurons in higher auditory areas respond to complex acoustic features, we devised a new approach that utilizes feature detectors to categorize the vocal elements into the three vocalization types and cage noises. We find that this feature detector method performs remarkably well on budgerigar vocalizations, producing over 90% accuracy in identifying elements compared to human annotated categorization. |
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F01.00011: Small Molecule Encapsulation in H2O2 Reactive Nanoparticles Harper Cartwright This project investigates the ability of APP-103TM, a novel polymer-based nanoparticle, to encapsulate small molecules. APP-103TM contains a polyoxalate ester that scavenges the reactive oxygen species (ROS) hydrogen peroxide, which is a cause of a condition known as acute kidney injury. This research explores the conditions needed for APP-103TM to be able to encapsulate additional components to expand its functionality. This is done by adding small molecules such as dyes during the formation of APP-103TM, which is made via an emulsification-solvent evaporation method. Techniques including absorption spectroscopy and energy-dispersive x-ray spectroscopy (EDS) can be used to observe whether or not these components are successfully encapsulated. It is also necessary to determine the mechanisms by which they get released from the particle cores, as well as whether these additional small molecules affect the functionality of APP-103TM. |
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F01.00012: Impedance spectroscopy of high performance bulk-heterojunction solar cells: detecting signature of low bandgap states Marian B Tzolov, Ilia Ivanov The advancement of organic photovoltaics was acceleration by the development of novel push-pull polymers and of non-fullerene acceptors. Simultaneously, the level of impurities and structural defects during the material synthesis were decreased substantially. Further improvement depends on small amounts of imperfections leading to subgap energy states that may act as recombination centers, or as traps for charge carriers. The trapped change may modify the internal electric field, and hence the collection efficiency of photovoltaic devices. We have studied the properties of temperature dependence of subgap energy states using impedance spectroscopy in dark and under visible light illumination, under increasing electric field. The impedance spectra detect states whose occupancy changes as result of the applied oscillating voltage. Our results show increase of the impedance response up to ten time when charge carriers are generated in the devices, e.g. temperature excitation, injection by external bias, and light illumination. The observed trends suggest the presence of trap-and-release processes, which are strongly affected by temperature, and external bias, which is consistent with the disordered nature of the bulk-heterojunction films. The use of different interfacial layers has little effect on these observations, which confirms that these are intrinsic properties of the bulk-heterojunction films. |
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F01.00013: Vector EIT magnetometer for highly sensitive measurements. Mario Gonzalez Maldonado, Alex Toyryla, Isaac Fan, Yang Li, John E Kitching, Jamie McKelvy, Andrey B Matsko, Eugeniy Mikhailov, Irina B Novikova We experimentally develop a novel and highly sensitive approach to measuring a vector magnetic fields using electromagnetically induced transparency (EIT) resonances. When an atom interacts with a bi-chromatic field in a two-photon configuration, the medium becomes transparent if the frequency difference between the fields is close to the energy separation between two Zeeman sublevels. As a result, a narrow transition peak appears in the transmission spectrum for all the allowed resonances. The magnitude of the magnetic field determines the separation between EIT spectrum peaks, and its orientation modifies the resonance amplitudes, making this system capable of vector measurements. Here we report our evaluation of the short-term stability and sensitivity of our prototype: we were able to achieve scalar stability below 10 pT/rtHz in the 10Hz-100Hz bandwidth using a 100mm3 vapor cell of hot 87Rb atoms, and sensitivity better than 1° for azimuthal magnetic field angle detection. |
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F01.00014: Magnetic Field Suppression System for the Measurement of the Cs Ground State Tensor Polarizability Andrew McConnell, Zhenyu Wei, David S. Weiss An improved Cs Ground State Tensor Polarizability (GSTP) measurement will provide a test for atomic theory used in atomic parity non-conservation measurements. The GSTP measurement is sensitive to background magnetic field fluctuations on the order of a few mG, despite a magnetic shield surrounding the Cs atoms. These background magnetic fields can fluctuate at a rate of 5 mG over a few minutes, a rate much faster than the current apparatus can correct for. To quickly suppress background magnetic fields, we are building a feed-forward system that monitors the B-field change using a magnetometer and cancels it by slightly changing the current flowing in a set of large Helmholtz coils that surrounds the apparatus. The efficacy of the suppression system at the point of the experiment will finally be determined using the trapped atoms, with an expected suppression of field fluctuation by a factor of ten. |
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F01.00015: A Microwave Atom Chip for Spin-Specific Trapping William Miyahira, Jordan Shields, Cate Sturner, Seth Aubin We present progress towards the development of an atom chip for producing spin-specific trapping potentials via the microwave AC Zeeman (ACZ) effect. These spin-specific potentials have applications in atom interferometry, quantum gates, and 1D many-body physics. Our design employs multiple parallel microstrip transmission lines to produce circularly polarized magnetic fields used for trapping. Additionally, the chip features several wires for traditional DC trapping. Axial confinement is provided by a microwave lattice based on the ACZ or AC Stark effect. A key necessity of this scheme is precisely phase-controlled microwaves, which we accomplish through IQ modulation. ACZ potentials offer the ability to produce a spin-specific trap for neutral atoms, use phase and detuning to control trap parameters, and suppressed potential roughness over DC atom chip traps. To couple broadband microwaves onto the atom chip we have designed a tapered microstrip wedge. We present simulation and prototype work on this coupling scheme. |
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F01.00016: Towards Mapping Gravity and High-order Derivatives with a Compact Atom Interferometer Timothy Nguyen, Hanbo Yang, Guanghui Su, Shi Wang, Jose Dominguez, Xuejian Wu Exploiting the nature of quantum phenomena, quantum technologies are developing rapidly towards precise sensing. Atom interferometers (AI) are robust quantum sensors and are being developed for measuring inertial forces. In contrast to classical sensors, atom interferometers use recoil momentum from photon and matter-wave interactions to coherently split and recombine matter-waves making AIs incredibly accurate and ideal sensors for precision measurements. Recently, transportable quantum gravimeters have been demonstrated for mobile gravimetry, however, they are limited to the second-order derivative of gravity, the gravity gradient. High-order gravity tensor is more sensitive to density variations, thus localizing and revealing the edge information of the gravity anomaly. We aim to develop the next-generation mobile quantum gravimeter with the capability of simultaneously mapping the vertical gravity, gravity gradient, and its second spatial derivative (curvature), and apply the quantum sensor for geophysics investigations. We optimize the AIs by driving the stimulated Raman transitions on the Rb hyperfine energy levels, maximizing the Rabi frequency, minimizing the single photon scattering rate, and zeroing the AC Stark shift. We test and characterize a novel diamond-shaped mirror for magneto-optical trapping three vertically separated cold atomic clouds using a single laser beam in order to reduce the complexity of forming three AIs necessary to resolve the gravity curvature. |
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F01.00017: Towards atom interferometry with atoms around an optical nanofiber Guanghui Su, Hanbo Yang, Timothy Nguyen, Shi Wang, Nami Uchida, Xuejian Wu Light-pulse atom interferometry was invented in the 1990s and it has become a precise tool to measure inertial forces and test fundamental laws of physics. Using laser-cooled atoms as the coherence source and photon-atom momentum transfer to split and combine matter waves, atom interferometers have applications in mobile gravimeters and inertial sensors. As their sensitivity scales with the light-atom interaction time, compact atom interferometers usually require a physical size from a few centimeters to a meter to allow the atoms to free-fall. On-chip atom interferometers have not yet been reported. Here, we propose a new type of atom interferometer using an evanescent field from an optical nanofiber. Because the waist of the optical nanofiber is thinner than the laser wavelength, the optical nanofiber will not only guide the laser beam but also produce a tight-confinement evanescent field. We will first use a two-color optical lattice from the evanescent field to trap the atom above the nanofiber, and then create the atomic superpositions by Bloch oscillation with a moving optical lattice. Recently, we have successfully fabricated optical nanofibers by tapering regular single mode fibers to a waist diameter of 200 nm and waist length of 5 mm with a laser transmission of 97%. We simulated the optical trapping with the evanescent field from an optical nanofiber and Bloch oscillation in the evanescent lattice. Now we are building a magneto-optical trap of Rb atoms and loading them on the optical nanofiber. |
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F01.00018: Dust attenuation laws of the SINGS/KINGFISH galaxies using Swift/UVOT Alexander Belles, Caryl Gronwall, Michael Siegel We study the variety of dust attenuation laws in the SINGS/KINGFISH galaxies derived via spectral energy distribution (SED) fitting, incorporating new NUV observations from the Swift UV/Optical Telescope (UVOT). The addition of Swift/UVOT integrated light photometry to archival multi-wavelength data improves our ability to determine the slope of the attenuation law and the strength of the 2175 Å dust bump. Due to the degeneracy between dust and the age of the underlying stellar population, we perform SED fitting using three different star formation history (SFH) parameterizations: a decaying exponential, double power law, and nonparametric piecewise function. We find that the slope of the average attenuation law can vary depending on SFH used. Additionally, we find that fits with UVOT data result in systematically lower bump strengths compared to fits with GALEX alone, demonstrating the utility of UVOT data in determining dust attenuation laws in the local universe. We argue for the use of the nonparametric piecewise SFH as it does not impose a rigid shape like parametric methods. Future work is needed on a larger sample to study population level trends and to account for any selection bias effects.
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F01.00019: GPU Accelerated MagnetoHydroDynamics for Astrophysics & Testing for Exascale Codes Robert Caddy, Evan Schneider Magnetic fields play a significant role in galaxy evolution because they have similar energy densities to the fluid. Magnetic fields would also enable anisotropic conduction and cosmic ray transport to be accurately simulated. Unfortunately, magnetohydrodynamical (MHD) simulations of galaxies are incredibly computationally expensive to run to the point where MHD simulations of entire galaxies have been impossible to perform at high resolution. |
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F01.00020: A Census of Blue Post-Horizontal-Branch Stars in Galactic Globular Clusters Akshat Chaturvedi, Gautam Nagaraj, Robin Ciardullo, Howard E Bond, Mike Siegel Globular clusters are some of the oldest astronomical objects in the universe. They contain within them, tens of thousands of stars, and are a gateway to understanding and determining the age of the universe. Despite their frequent occurrence, there are still parts of globular clusters that are yet to be completely understood or surveyed. One such aspect is the presence of blue, post-horizontal-branch (HB) stars. These stars are rare, tend to emit most of their light in the UV band, and have properties that can be useful in further understanding how globular clusters develop. The literature surrounding globular clusters has determined that yellow post-asymptotic-giant-branch (AGB) stars can be used as standard candles to verify distance measurements. Our study looks to extend this to blue post-HB stars as well. As part of our analysis, we took a look at 109 globular clusters present in the Milky Way and the Magellanic Clouds, using data collected by the Cerro-Telolo Inter-American Observatory (CTIO) and the Kitt Peak National Observatory(KPNO). These data consisted of photometric measurements of the stars in the Thuan-Gunn u, and Johnson B, V and I bands. We constructed color-magnitude and color-color diagrams of these clusters, using which we were able to create a census of such blue (having a (B-V)0 <-0.05) post-HB stars. We used a mix of positional and photometric data from the Gaia Data Release 3 and a density-based spatial clustering algorithm (DBSCAN) to verify cluster membership of these stars and eliminate field stars present in our original photometric data. Our final analysis will allow us to create the largest sample of extremely blue post-HB (EHB )stars ever compiled, trace the various evolutionary scenarios of EHB stars, and better test the hypothesis that post-AGB stars in old stellar populations are excellent standard candles for extragalactic distance measurements. |
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F01.00021: Automating Veto Algorithms for Application to the Search for Burst Gravitational Waves with LIGO Michael C Davis, Amber Stuver This research has applied automated veto (glitch rejection) tools to evaluate their potential to improve the search for burst (unmodelled) gravitational waves with LIGO (Laser Interferometer Gravitational-Wave Observatory). During the process of data acquisition, transient noise from environmental and instrumental sources creates glitches in the data. The impact of these glitches on the search for gravitational waves can be mitigated by removing (vetoing) these glitches from the data. Auxiliary channels, data streams that are unable to detect gravitational waves, are used to generate glitches and minimize the chance that a glitch may be a true gravitational wave. Omicron is an algorithm that is currently used to automatically identify data segments likely to be glitches. Two different statistical algorithms evaluate data quality when Omicron glitches originating from different auxiliary channels are vetoed: hierarchical veto (Hveto) and Used Percentage Veto (UPV). We have developed software to collect the daily results of Hveto and UPV and apply those candidate vetoes to the burst search algorithm, Coherent WaveBurst (cWB). The results are evaluated by the Veto Evaluation Tool (VET) to measure a veto’s efficiency (fraction of the background events that were vetoed) in removing cWB triggers, deadtime (amount of time removed by the veto), and the ratio of efficiency to deadtime. The higher this ratio, the more effective the veto. Results of this research show that Hveto and UPV provide vetoes that identify unique glitch features, and both have the potential to improve data quality for burst gravitational wave search. New features have been added to assist data scientists in identifying problematic channel sources. This material is based upon work supported by the National Science Foundation under Grant PHY-2110157. |
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F01.00022: NEID Reveals that The Young Warm Neptune TOI-2076 b Has a Low Obliquity Robert C Frazier, Gudmundur Stefansson, Suvrath Mahadevan TOI-2076 b is a sub-Neptune-sized planet (R = 2.39 Eath radii) that transits a young (200Myr) bright (V = 9.2) K-dwarf hosting a system of three transiting planets. Using spectroscopic observations with the NEID spectrograph on the WIYN 3.5m Telescope we model the Rossiter-McLaughlin effect of TOI-2076 b, and derive a sky-projected obliquity of -3 (+/- 16) degrees. Using the size of the star (R = 0.775 Solar radii), and the stellar rotation period (Prot = 7.27 days), we estimate a true obliquity of 18 (+/-10) degrees, demonstrating that TOI-2076 b is on a well-aligned orbit. The RV observations exhibit a large inverted and chromatic RV slope, which we attribute to stellar activity. Simultaneous diffuser-assisted photometry from the 3.5m Telescope at Apache Point Observatory rules out flares during the transit. TOI-2076 b joins a growing sample of young planets and compact multi-planet systems with well-aligned orbits. The low obliquity of TOI-2076 b and the presence of transit timing variations in the system suggest the TOI-2076 system likely formed via convergent disk migration in an initially well-aligned disk. |
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F01.00023: Characterizing Dark Current of Two Novel Speedster-EXD550 X-Ray Hybrid CMOS Detectors Evan C Jennerjahn, Abraham Falcone, Joseph M Colosimo, Hannah M Grzybowski, Mitchell Wages, Jacob Buffington, David N Burrows, Fredric Hancock, Jordan Josties, Lukas R Stone For space-based X-ray applications, silicon hybrid CMOS detectors (HCDs) offer many advantages over CCDs such as faster readout rates and in-pixel circuitry. Achieving low noise in X-ray applications of HCDs helps to achieve better energy resolution, so understanding their dark current and read noise is a high priority. Dark current is a type of noise resulting from thermal energy exciting electrons in the detector. It is temperature dependent, so cooling the detector is the best way to minimize its effects. Cooling detectors is costly for CubeSats, so it is important to characterize dark current at the temperatures the detectors will see in orbit. The BlackCAT CubeSat is a Coded Aperture Telescope that will search the soft X-ray sky for high-energy astronomical transients. It is a 6U CubeSat mission using an array of four Speedster-EXD550 X-ray HCDs. Here, we analyze the dark current of two Speedster-EXD550s. |
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F01.00024: Implement Probability Estimator of Astronomical Events in G-wave Search Victoria Niu Laser Interferometer Gravitational-Wave Observatory (LIGO) is one of the leading experiments in detecting cosmic gravitational wave. Using the wave templates of binary systems from numerical relativity, LIGO have found 90 gravitational wave events whose signals are generated by binary black hole coalescence (BBH), binary neutron star coalescence (BNS), and neutron star – black hole coalescence (NSBH). GstLAL is one of the searching programs developed for identifying G-wave events in the noise data. As the number of gravitational wave sources are increasing with more observation, how to accurately estimate the probability of the astronomical source of a detected event becomes a necessary question. Although there has been theoretical work on how to calculate this probability, the GstLAL team at Penn State carries out a data-based approach to this estimation and implements a software tool to complete the computation. The software infrastructure is necessary in order to handle the large dataflow from LIGO O4 observation which is expected to find over hundreds of gravitational wave events. The statistic principle behind this method is the Bayes Theorem: P(A|B) = P(B|A)P(A)/P(B) where A serves as some detected data of gravitational wave, and B is one of the categories in BBH, BNS, and NSBH. Probability of data given category P(B|A) and probability of data P(A) are postulated from our G-wave database, while probability of category P(B) is treated as a marginalized term. The estimated probability of category given data P(A|B) is used to determine the candidacy of our observed events, along with the comparison from theoretical calculation. This probability estimator is currently implemented to the offline search of LIGO O4 run. |
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F01.00025: A new explanation of redshift and blueshift phenomena (using movment light source) Gh. Saleh It can be said that an electromagnetic wave has the parameters of wavelength (λ) and amplitude (a), which are particular values for each light. In fact, the certificate of a wave is its wavelength and amplitude. It should be noted that the relation λ ≈ 4a always holds true. On the other words, wavelength and amplitude are dependent on each other and the wavelength is a coefficient of the amplitude. |
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F01.00026: Why is the earth far from the sun Han y yong Quan, Meng Zhaoqiang Both the sun and the earth are radiating, and there are mass and energy conversions. Radiation is a process in which mass is converted into energy. The conversion of mass and energy follows Einstein's mass energy equation: E=mc ^ 2. In other words, the mass of the system composed of the sun and the earth is decreasing. The system composed of the sun and the earth follows the system constant equation I summarized: M ^ 2R=Q, Q is a constant, M decreases, R will increase, and the radius of mutual rotation of the system composed of the sun and the earth will increase, and the resulting result is that the earth is away from the sun, which is the real reason why the earth is away from the sun. According to the law of universal gravitation, we can also know that when the distance between two mutually rotating objects increases, the rotation speed will inevitably decrease, and the rotation speed will decrease. We can also conclude that the speed of the earth's revolution around the sun is also decreasing. It can be inferred that the moon is far away from the earth and the solar system is far away from the center of the Milky Way. The same reason is why the universe is expanding. |
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F01.00027: Preliminary Faraday Rotation Results Associated with the Photoionized Gas of IC 1396 Ramisa A Rahman, Allison H Costa We present initial Faraday rotation measurements of extragalactic radio sources with lines of sight passing through or near to the HII region of IC 1396. We measured the linear polarization of the sources with the Karl G. Jansky Very Large Array (VLA) at frequencies of ~5 GHz (6 cm) . We estimate the background rotation measure (RM) in this region of the galaxy to be ~ -140 m^-2. We find the sources having lines of sight passing through IC 1396 have an excess rotation measure of |RM| ~ 62-465 rad m^-2 with respect to the background. We will discuss rotation measure values in the context of magnetized plasma of IC 1396. We compare our results to known models of rotation measure in our galaxy. |
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F01.00028: Open Data and Open Science in Heliophysics Thomas Y Chen, Alexa Halford, Luke Rastaetter Findable, Accessible, Interoperable, and Reusable (FAIR) data are essential to heliophysics, indeed all scientific research. The principals of FAIR data ensure the reusability and finability of data as well as its long term care. The goal is that the data are accessible for the ongoing process of discovery and verification and can be used on its own or with newly generated data in future studies leading to new innovations. With the onset in the previous decades of NASA and other agencies requiring mission data to be open to the public, Heliophysics has already made great strides towards FAIR data and benefited from these efforts. Continued improvements with our metadata, data archives, and data portals, and the addition of DOIs to cite data will ensure data will be FAIR, enabling further scientific discoveries, reproduciblility of results, longitudinal studies, and verification and validation of models. Currently, not all the data collected is findable and on open networks or archives, and not all data on archives have DOIs. Within this paper we make recommendations intended to prioritize resources needed to satisfy FAIR data principles, treating them as a fundamental research infrastructure, rather than a simple research product. |
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F01.00029: AI for High Energy Physics: Interpretable Uncertainty Quantification Thomas Y Chen, Biprateep Dey, Aishik Ghosh, Michael Kagan, Brian Nord, Nesar Ramachandra Estimating uncertainty is at the core of performing scientific measurements in HEP: a measurement is not useful without an estimate of its uncertainty. The goal of uncertainty quantification (UQ) is inextricably linked to the question, "how do we physically and statistically interpret these uncertainties?" The answer to this question depends not only on the computational task we aim to undertake, but also on the methods we use for that task. For artificial intelligence (AI) applications in HEP, there are several areas where interpretable methods for UQ are essential, including inference, simulation, and control/decision-making. There exist some methods for each of these areas, but they have not yet been demonstrated to be as trustworthy as more traditional approaches currently employed in physics (e.g., non-AI frequentist and Bayesian methods). Shedding light on the questions above requires additional understanding of the interplay of AI systems and uncertainty quantification. We briefly discuss the existing methods in each area and relate them to tasks across HEP. We then discuss recommendations for avenues to pursue to develop the necessary techniques for reliable widespread usage of AI with UQ over the next decade. |
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F01.00030: Sensitivity Estimates of Mountain-Top Neutrino Telescopes Anushka Durg, Austin Cummings, Stephanie A Wissel High-energy neutrinos can be used to probe astrophysics and particle physics at the highest energies. On a high-elevation mountain, we have two options for detection: optical and radio emissions. We specifically consider tau neutrinos, which, at the highest energies, skim the Earth's surface and interact, allowing for the production of an extended (km-scale) shower of particles in the air. Many proposed experiments seek to observe these showers through direct detection of the secondaries in the shower as well as the emission they produce, including radio, fluorescence, and optical Cherenkov. |
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F01.00031: Interferometric Reconstruction of Radio Signatures of Air Showers from a High-Elevation Mountain Grant Sommer, Stephanie A Wissel, Austin Cummings, Andrew J Zeolla Ultra-high energy neutrinos can give us a unique view into high energy physics processes in our universe. The Beamforming Elevated Array for Cosmic Neutrinos (BEACON) aims to detect tau neutrinos with energies in excess of 100 PeV. Tau neutrino interactions in the Earth can generate tau leptons that escape and decay to produce air showers. By pointing a radio interferometer at the horizon from a high-elevation mountain, BEACON is optimized to search for the radio signature induced by the decays of tau leptons. The prototype, located in the White Mountains of California, operates in the 30 to 80 MHz range. I will discuss an ongoing study aimed to reconstruct the Xmax with BEACON and direction using interferometric techniques. Preliminary studies using microscopic models of radio emission from cosmic rays show good performance in reconstructing Xmax and we will apply these techniques to tau leptons in future work. |
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F01.00032: Definitions of Graduate Student Success in Physics for Faculty, Students, and Alumni Kevin Honz, Nic Atkinson, Louis Leblond, Eric W Hudson Graduate student success in physics is an essential yet amorphous concept for graduate education. Education researchers, admissions committees, and program reformers utilize implicit or explicit definitions of graduate student success that allocate different aspects importance. These aspects of success may come from the breadth of the graduate student experience: research, academics, teaching, degree obtainment, professional success, social success, and personal success. We developed a survey measuring the importance of 36 aspects of success to 147 respondents from a single institution. Faculty, students, and alumni mostly agree on definitions of success at the population level. Education researchers should know the objective metric of success that was most important was degree completion, as seems broadly assumed in the literature. Admissions committees should know and consider broadcasting to potential students that this institution most valued independently carrying out research and continuously learning throughout their career as aspects of defining success. Program reformers should know that all three groups viewed ability to continue in desired career path significantly more important than the ability to continue in academia and thus reformers should consider professional development opportunities and mentoring for non-academic track students. |
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F01.00033: Study on Financial Physics in Exchange Rates Using Neural Network and Statical Simulations Richard Kyung, Dohyun Ahn, Minjun Kim Exchange rates play a vital role in a country's trade practices, which is critical to every free market economy in the world. Therefore, these rates are often among the most analyzed and manipulated economic measures. It is the rate that one currency can be exchanged for another between nations or economic zones. Therefore, it can be used to determine the value of various currencies in relation to each other. It is critical in determining trade and capital flow dynamics. |
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F01.00034: Effects of Gamma-Ray Irradiation on Physicochemical Properties of MoSe2 Javari Cherry, Burcu OZDEN, Teresa Aditya, Zhouhang Yu, Jean Paul Allain, Mauricio Terrones Space tourism is expected to become a large industry within the next decade as more private sector companies promote it.This ambitious goal can only be achieved through: (1) the discovery of radiation-resilient materials that exceed the stability and reliability expectations beyond existing semiconductor materials subjected to harsh environments, and (2) the development of radiation-robust technologies with expanded capabilities yet reduced size and weight. In this regard, 2D materials have attracted considerable attention for space applications due to their potential use as a replacement of traditional semiconductors for next-generation electronic devices and circuits. Among these materials, molybdenum diselenide (MoSe2) becomes a suitable candidate due to its attractive semiconducting properties, strong chemical bonds, low optical absorption and absorption, bandgap tunability, and remarkable mechanical properties. In this study, we report the first structural, optical, and chemical analysis of chemical vapor deposition (CVD) grown MoSe2 flakes to various gamma radiation dosages up to 10MRad to understand their radiation stability for space and nuclear applications. In general, very small changes in optical, structural and chemical properties were observed compared to pristine samples, suggesting noteworthy stability even for high dosages of gamma radiation. We found out that low energy irradiation reduces the already existing Se vacancies causing improved optical properties. These findings highlight the inherent stability of these 2D quantum materials in harsh radioactive environments, which motivates further investigation of their optical, electrical, and structural properties and exploration for use in future space, energy, and defense applications. |
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F01.00035: Electrodeposition of Copper-Manganese onto Porous Nanowire Foams Thomas Hulse, James Malloy, Erin L Marlowe, Isaac Liu, Kai Liu Nanoporous metallic foams constructed from electrodeposited nanowires have recently been shown to be highly efficient in filtering sub-micron particulates while preserving a low weight and high robustness [1]. Such foams are promising filtration media against air pollution as well as the on-going COVID-19 pandemic. An additional functionality of the foams is the potential to efficiently catalyze toxic and greenhouse gases simultaneously with physical filtration. We have successfully coated copper-manganese alloys as catalysts onto copper nanowire foams using electrochemical deposition. Cyclic voltammetry, scanning electron microscopy, and energy-dispersive X-ray spectroscopy confirm the successful formation of a homogeneous and porous copper-manganese coating onto the metallic foams, with the desirable composition. Such CuMn-coated foams offer potential in improving the catalytic reduction of carbon monoxide. |
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F01.00036: Analyzing Simulated Spectra of Cool Ionized Clouds in the Circumgalactic Medium Sofia Martinez Fortis, Evan Schneider, Alwin Mao Galactic winds are targets of interest for studying galaxy evolution, for they provide information regarding star formation and the mass-metallicity relation. Astronomers use quasar absorption lines to study clouds of gas in the circumgalactic medium (CGM), which may yield information about galactic winds. However, due to the uncertain nature of quasar spectra, mock observations from hydrodynamic galaxy simulations prove to be useful tools for better understanding observational data. In this project, I create and analyze mock absorption-line spectra using data from the hydrodynamic galaxy simulation, CHOllA, to help constrain the CGM and provide useful information that facilitates the interpretation of quasar absorption-lines. I focus on the abundance of some commonly observed ions through gas of varying temperature, density, and line-of-sight velocity. |
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F01.00037: 1D Confinement of 4He Inside Cesium-Plated MCM-41 Nanopores Stephanie McNamara, Paul E Sokol, Garfield T Warren
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F01.00038: NeuroART: Real-time analysis of neuronal population activity for informed closed-loop experiments Douglas Scalioni Domingues, Dulara De Zoysa, Wolfgang Losert Two-photon (2P) calcium imaging allows for the activity readout of large populations of neurons at single cell resolution, and holographic optogenetics makes the population accessible for targeted stimulation. However, significant pre- and post-processing is required to interpret signals from large datasets, which leads to the selection of stimulation targets based only on rudimentary qualitative criteria. We have developed NeuroART (Neuronal Analysis in Real Time), a software that accesses microscope data streams to provide real-time readout of neuronal activity, downstream analysis, and photostimulation during image acquisition. |
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F01.00039: Effects of X-Ray Exposure on Physical Characteristics of Metallic Thin Films Dorothy E Doughty This experiment is designed to understand the impacts of broad spectrum radiation on metallic films with emphasis on corrosion resistance. There was an analysis of depositions of films on a silicon substrate: Copper, Titanium, Titanium Nitride, Silver, and Aluminum. These depositions were analyzed through Scanning Electron Microscroscopy and Energy Dispersive X-ray Spectroscopy then irradiated through a rhodium source. These atomic compositions of these samples were compared before and after x-ray exposure and determined to have an increase in oxygen composition. These x-rayed films underwent a series of acid etching tests and the x-rayed samples had an increased resistivity to corrosion. The resistivity was visual in decreased pitting in the films. The composition of the oxide layer was analyzed through the SEM. This experiment showed an increase in oxygen content for all materials irradiated with a rhodium source. Evidence suggests x-rays induced a reaction at the surface which creates an oxide layer for all materials investigated. In most instances, the oxide layer forms a corrosion resistant surface layer. Limited evidence suggests an improvement in adhesion resulting from oxygen availability at the coating and substrate interface. |
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