Physical Sciences

Observational Studies of the Solar System with the DECam Ecliptic Exploration Project

Our solar system is filled with yet undetected objects ranging from small asteroids to possible planet candidates. Such objects, such as the asteroids that are a part of the Main Belt between Mars and Jupiter present a unique challenge in detecting and tracking as their fast movement usually sees them moving out of the field range of a telescope on a given night. However, by linking long-stare asteroid streaks with shorter triple frame exposures taken as part of the DEEP DECam collaboration’s usage of the CTIO telescope, we are able to process 24 to 48 hour orbital arcs for these fast moving objects. In this presentation, we present and analyze data from near a thousand newly detected main-belt asteroids. Each component of the methodology is explained, and its processing efficiency demonstrated. A brief overview of the linking algorithm is also included.

X-raying the Milky Way: A search for interstellar dust clouds

This research is interested in discovering if there are interstellar dust clouds near stars that could be identified because of the interference they make with X-ray imaging, which would normally be difficult to detect because of their proximity to the star. Nearby dust clouds act as X-ray “mirrors” that reflect and scatter the rays, causing a notable phase shift that can be used to identify the clouds. This research aims to develop tools to aid in analyzing X-ray data collected from stars in order to identify such clouds. This was achieved through the creation of image analysis algorithms made and used in the python environment Spyder. In addition to this, the library astropy was also used to manipulate and analyze table data to help develop these algorithms. Algorithms based on the idea of centering the x-ray image of the star to perform a radial analysis of its surroundings will be able to help identify these clouds. Since the algorithms are still being developed and perfected, the research hopes to be able to find new dust clouds, or confirm that none exist, by testing the algorithms on well-documented stars. With this, the research will be able to confirm or deny dust clouds near stars and thus help other astronomers account for them.

X-Raying the Milky Way: Building a Database of X-Ray Lighthouses

An X-ray dust scattering halo occurs when a large amount of dust gathers between Earth and a bright X-ray source. As the light from the source travels through space, it scatters when it hits the interstellar dust, allowing us to study the dust (Heinz). Several different types of dust echoes can be observed, including constant dust scattering halos, variable dust scattering halos, and X-ray ring echoes. Constant dust scattering halos are easy to see, while X-ray ring echoes are rare and bring with them an abundance of data (Heinz). This is because X-ray rings “require short, bright flares of the source followed by quick dimming” to be seen, while constant dust scattering halos need a thick sheet of dust between Earth and them to form (Heinz). Unfortunately, it is rare to see these dust echo rings with the current technology and satellites in orbit. But the telescope Athena will be launched in 2030 and will allow for 30 times more observations than the latest telescope, Chandra (Corrales 2019). Corrales et al. determined how powerful Athena will be by studying past dust echoes and the outbursts that created them with MAXI data (Corrales 2019). For my UROP project, I compiled a spreadsheet of X-ray Targets and data about them. This information will be useful for Dr. Corrales’s research group and will serve as a valuable reference while continuing their work on dust-echo tomography. Works Cited Corrales L., Mills B., Heinz S., Williger G., 2019, “˜The X-Ray Variable Sky as Seen by MAXI: The Future of Dust-echo Tomography with Bright Galactic X-Ray Bursts’ The Astrophysical Journal 874:155 Heinz S., Corrales L., “˜X-ray Dust Tomography: the New Frontier in Galactic Exploration’ CXC Newsletter

Dark Matter searches with LZ

In the universe, the orbital mechanics of stellar objects is explained by their gravity and hence their mass. For example, our understanding of gravity tells us that when an object orbits an amount of matter gets farther away from that mass, the object’s orbital velocity will decrease. Using optical observations of galaxies we observe that their matter is concentrated at their center. However, we measure the velocity of stars at the fringe of galaxies, their velocities are much faster than what we would expect. To explain this observation, many scientists believe that some sort of invisible matter exists that causes these observations. It is known as Dark Matter. The LUX Zeplin team is currently building a detector one mile underground to discover if this matter exists. Later in 2021, the LZ detector will finally go online and start to collect data. It is expected that if Dark Matter exists, it is a particle that would have a mass of 1 GeV or thousands of GeV heavier. The team hopes that the detector will be able to observe particle interactions, among them rare dark matter interactions, and be able to analyze them to search for these Dark Matter events. Then LZ physicists will analyze this data and will come to a conclusion on dark matter’s existence. If found, this new type of matter will help explain orbital velocity observations and may even deepen our understanding about the development of the universe.

Characterizing Black Hole Binary Outbursts: X-ray Characterization of AT2019wey

AT2019wey is a transient optical source discovered in late 2019 and identified as a bright X-ray by the eROSITA X-ray telescope in early 2020. The nature of the source is unknown, with the source location and outburst properties suggesting an origin in a Galactic low mass X-ray binary. Herein, we present an analysis of multiple observations of AT2019wey made by the Neil Gehrels Swift Observatory over the course of 6 months in 2020. X-ray spectra in the 1 – 10 keV energy band have been modeled with an absorbed power-law model to study the temporal evolution of the X-ray properties of the source. Over time, the power-law photon index is observed to increase as the source brightened, consistent with the emergence of a prominent accretion disk. We discuss the results of this analysis and place constraints on the nature of this system in the context of models for accreting black holes and neutron stars.

Transient and Variable Sources in the Gaia and Chandra Catalogs

Large scale datasets are now being created across multiple wavelength regimes, and are crucial tools in our effort to probe many questions in Astronomy. Herein, we present an effort to identify candidate black hole and neutron star binaries via a cross comparison of the variable stars identified in the GAIA DR2 data release comprising >600 thousand sources and the population of >300 thousand X-ray sources identified by the Chandra X-ray telescope. Data from the GAIA catalog has been filtered to create a table for comparison with the point sources in the Chandra Source Catalog. We will present the results of this comparison and discuss the possibilities of comparing the different data sets. While this project focused on isolating a subset of stars from the GAIA data, the process of doing so and the comparisons made are just the first steps of what can be done with these data sets and what can be done on a much larger scale.

Kinematic Distributions and Higgs Decay

The use of relativistic kinematics to study individual elementary particles is critical in understanding what specific motions and processes take place in experimental settings at high-energy particle physics accelerators. The purpose of this research project is to analyze the relativistic kinematics present at the Large Hadron Collider for different particles and better understand the mechanics of such targets while they are being influenced by special relativistic effects. Moreover, we investigate two-body decay events of the Higgs boson particle and how this may play a role in laboratory settings. Using kinematic distributions with Python software to vary certain parameters, such as incident angles or mass, we can understand how this may affect the energies of particular particles, for example. We hope to use these methods to understand Higgs decay to various particles and investigate how various factors may influence these events. This study helps to interpret how the effects of relativity play a role in Higgs decay and the motions of elementary particles so that one may be able to predict behaviors that would take place in the lab. We hope to find consistent behaviors of these particles in regards to the special theory of relativity and better understand what is taking place during Higgs decay and at the Large Hadron Collider.

Rb Magnetometer Evaluation for nEDM Experiment

The neutron electric dipole moment (nEDM) experiment at Los Alamos National Laboratory will require the magnetometers to monitor the temporal change of the magnetic field and gradient of the magnetic field in the apparatus with precision of 50 femtoTesla (fT) and 100 fT/15cm, respectively. We evaluate commercial rubidium based magnetometers as candidates for use in the experiment by investigating their clock frequency bias, internal noise, and gradient drift sensitivity. We make these measurements in our lab with an apparatus consisting of three magnetometers linearly spaced, and parallel to the axis of a solenoid surrounding them. The solenoid produces a uniform magnetic field and is surrounded by a two or three layer magnetic shield. Measurements from all three magnetometers are used to gather the individual magnetometer readings, difference of pairs, average of three, first order gradients, and second order gradients. These metrics are evaluated with Allan Deviation studies to quantify their stability. QuSpin’s Total-Field Magnetometer (QTFM) shows promising results because its clock frequency bias is negligible, and it has a field sensitivity below 40 fT when averaged over 10 seconds. Additionally, we plan to evaluate custom magnetometers from Twinleaf, LLC.

Finding New Planets Around Ancient Stars

The observation of exoplanets orbiting ancient stars allows us to understand not only distant solar systems inhibiting these worlds but our own solar system as well. In particular, the method of locating and analyzing these exoplanets allows us to delve into a deeper understanding of host stars and planets themselves. However, there are a limited number of methods in finding these exoplanets, as well as difficulty in overcoming observing inaccuracies when perceived from Earth. With the transiting lightcurve method and the collection of data from the Transiting Exoplanet Surveying Satellite (TESS), we are able to more efficiently observe details of transiting planet events through the change in flux of a host star. This results in thousands of stellar light curves to examine in order to detect planet candidates, binary stars, variable stars, and other stellar phenomena. The successful finding of an exoplanet through this method allows a multitude of future investigations to take place such as atmospheric analysis and astrobiological implications.

Experimental studies of high-energy quantum chromodynamics

With the advent of new technologies in the world of particle physics comes a realm of new areas of exploration within the field. One of these areas is hadronization within quantum chromodynamics, the study of interactions between quarks and gluons, which has largely been unexplored. To fill in some of the gaps in scientists’ knowledge in this area on how quarks and gluons, elementary particles that are part of the standard model, form hadrons, composite particles made from quarks, my research will investigate jet substructure observables along with correlations between strange and anti-strange particles within jets in proton-proton and electron-proton collision simulations generated with Pythia. As these topics are fairly new to the field of quantum chromodynamics, the measurements we take will be the first of their kind. These measurements will be done through Pythia for digital event generation and data organization will be done through ROOT in the form of ntuples and histograms. Following simulated data generation, ROOT will be used for data analysis to achieve final measurements on the topic. Research work from a former member of Dr. Christine Aidala’s research group, Dr. Joseph Osborn, on jet hadronization will serve as a comparison and motivation point for the research we will complete. The findings of this research will then motivate further studies in the study of hadronization and quantum chromodynamics and serve as a base comparison point for others who choose to measure strange and antistrange particles within jets.